3 perldiag - various Perl diagnostics
7 These messages are classified as follows (listed in increasing order of
10 (W) A warning (optional).
11 (D) A deprecation (enabled by default).
12 (S) A severe warning (enabled by default).
13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
15 (X) A very fatal error (nontrappable).
16 (A) An alien error message (not generated by Perl).
18 The majority of messages from the first three classifications above
19 (W, D & S) can be controlled using the C<warnings> pragma.
21 If a message can be controlled by the C<warnings> pragma, its warning
22 category is included with the classification letter in the description
23 below. E.g. C<(W closed)> means a warning in the C<closed> category.
25 Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
26 and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Severe warnings are always enabled, unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Allocation too large: %x
55 (X) You can't allocate more than 64K on an MS-DOS machine.
57 =item '%c' allowed only after types %s in %s
59 (F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60 after certain types. See L<perlfunc/pack>.
62 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
64 (W ambiguous) A subroutine you have declared has the same name as a Perl
65 keyword, and you have used the name without qualification for calling
66 one or the other. Perl decided to call the builtin because the
67 subroutine is not imported.
69 To force interpretation as a subroutine call, either put an ampersand
70 before the subroutine name, or qualify the name with its package.
71 Alternatively, you can import the subroutine (or pretend that it's
72 imported with the C<use subs> pragma).
74 To silently interpret it as the Perl operator, use the C<CORE::> prefix
75 on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
76 to be an object method (see L<perlsub/"Subroutine Attributes"> or
79 =item Ambiguous range in transliteration operator
81 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82 all. To include a C<-> character in a transliteration, put it either
83 first or last. (In the past, C<tr/a-z-0//> was synonymous with
84 C<tr/a-y//>, which was probably not what you would have expected.)
86 =item Ambiguous use of %s resolved as %s
88 (S ambiguous) You said something that may not be interpreted the way
89 you thought. Normally it's pretty easy to disambiguate it by supplying
90 a missing quote, operator, parenthesis pair or declaration.
92 =item Ambiguous use of -%s resolved as -&%s()
94 (S ambiguous) You wrote something like C<-foo>, which might be the
95 string C<"-foo">, or a call to the function C<foo>, negated. If you meant
96 the string, just write C<"-foo">. If you meant the function call,
99 =item Ambiguous use of %c resolved as operator %c
101 (S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
102 bitwise and, and multiplication) I<and> initial special characters
103 (denoting hashes, subroutines and typeglobs), and you said something
104 like C<*foo * foo> that might be interpreted as either of them. We
105 assumed you meant the infix operator, but please try to make it more
106 clear -- in the example given, you might write C<*foo * foo()> if you
107 really meant to multiply a glob by the result of calling a function.
109 =item Ambiguous use of %c{%s} resolved to %c%s
111 (W ambiguous) You wrote something like C<@{foo}>, which might be
112 asking for the variable C<@foo>, or it might be calling a function
113 named foo, and dereferencing it as an array reference. If you wanted
114 the variable, you can just write C<@foo>. If you wanted to call the
115 function, write C<@{foo()}> ... or you could just not have a variable
116 and a function with the same name, and save yourself a lot of trouble.
118 =item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
120 =item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
122 (W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
123 the name of a Perl keyword), which might be looking for element number
124 2 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
125 might have meant to pass an anonymous arrayref to the function named
126 foo, and then do a scalar deref on the value it returns. If you meant
127 that, write C<${foo([2])}>.
129 In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130 to disambiguate between array subscripts and character classes.
131 C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
132 by the character class C<[2345]>. If an array subscript is what you
133 want, you can avoid the warning by changing C</${length[2345]}/> to the
134 unsightly C</${\$length[2345]}/>, by renaming your array to something
135 that does not coincide with a built-in keyword, or by simply turning
136 off warnings with C<no warnings 'ambiguous';>.
138 =item '|' and '<' may not both be specified on command line
140 (F) An error peculiar to VMS. Perl does its own command line
141 redirection, and found that STDIN was a pipe, and that you also tried to
142 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
144 =item '|' and '>' may not both be specified on command line
146 (F) An error peculiar to VMS. Perl does its own command line
147 redirection, and thinks you tried to redirect stdout both to a file and
148 into a pipe to another command. You need to choose one or the other,
149 though nothing's stopping you from piping into a program or Perl script
150 which 'splits' output into two streams, such as
152 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
159 =item Applying %s to %s will act on scalar(%s)
161 (W misc) The pattern match (C<//>), substitution (C<s///>), and
162 transliteration (C<tr///>) operators work on scalar values. If you apply
163 one of them to an array or a hash, it will convert the array or hash to
164 a scalar value (the length of an array, or the population info of a
165 hash) and then work on that scalar value. This is probably not what
166 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
169 =item Arg too short for msgsnd
171 (F) msgsnd() requires a string at least as long as sizeof(long).
173 =item Argument "%s" isn't numeric%s
175 (W numeric) The indicated string was fed as an argument to an operator
176 that expected a numeric value instead. If you're fortunate the message
177 will identify which operator was so unfortunate.
179 =item Argument list not closed for PerlIO layer "%s"
181 (W layer) When pushing a layer with arguments onto the Perl I/O
182 system you forgot the ) that closes the argument list. (Layers
183 take care of transforming data between external and internal
184 representations.) Perl stopped parsing the layer list at this
185 point and did not attempt to push this layer. If your program
186 didn't explicitly request the failing operation, it may be the
187 result of the value of the environment variable PERLIO.
189 =item Argument "%s" treated as 0 in increment (++)
191 (W numeric) The indicated string was fed as an argument to the C<++>
192 operator which expects either a number or a string matching
193 C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
194 Auto-decrement> for details.
196 =item Array @%s missing the @ in argument %d of %s()
198 (D deprecated) Really old Perl let you omit the @ on array names in some
199 spots. This is now heavily deprecated.
201 =item A sequence of multiple spaces in a charnames alias definition is deprecated
203 (D deprecated) You defined a character name which had multiple space
204 characters in a row. Change them to single spaces. Usually these
205 names are defined in the C<:alias> import argument to C<use charnames>, but
206 they could be defined by a translator installed into C<$^H{charnames}>.
207 See L<charnames/CUSTOM ALIASES>.
209 =item assertion botched: %s
211 (X) The malloc package that comes with Perl had an internal failure.
213 =item Assertion %s failed: file "%s", line %d
215 (X) A general assertion failed. The file in question must be examined.
217 =item Assigning non-zero to $[ is no longer possible
219 (F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
220 the special variable C<$[>, which is deprecated, is now a fixed zero value.
222 =item Assignment to both a list and a scalar
224 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
225 must either both be scalars or both be lists. Otherwise Perl won't
226 know which context to supply to the right side.
228 =item Attempt to access disallowed key '%s' in a restricted hash
230 (F) The failing code has attempted to get or set a key which is not in
231 the current set of allowed keys of a restricted hash.
233 =item Attempt to bless into a freed package
235 (F) You wrote C<bless $foo> with one argument after somehow causing
236 the current package to be freed. Perl cannot figure out what to
237 do, so it throws up in hands in despair.
239 =item Attempt to bless into a reference
241 (F) The CLASSNAME argument to the bless() operator is expected to be
242 the name of the package to bless the resulting object into. You've
243 supplied instead a reference to something: perhaps you wrote
249 bless $self, ref($proto) || $proto;
251 If you actually want to bless into the stringified version
252 of the reference supplied, you need to stringify it yourself, for
255 bless $self, "$proto";
257 =item Attempt to clear deleted array
259 (S debugging) An array was assigned to when it was being freed.
260 Freed values are not supposed to be visible to Perl code. This
261 can also happen if XS code calls C<av_clear> from a custom magic
262 callback on the array.
264 =item Attempt to delete disallowed key '%s' from a restricted hash
266 (F) The failing code attempted to delete from a restricted hash a key
267 which is not in its key set.
269 =item Attempt to delete readonly key '%s' from a restricted hash
271 (F) The failing code attempted to delete a key whose value has been
272 declared readonly from a restricted hash.
274 =item Attempt to free non-arena SV: 0x%x
276 (S internal) All SV objects are supposed to be allocated from arenas
277 that will be garbage collected on exit. An SV was discovered to be
278 outside any of those arenas.
280 =item Attempt to free nonexistent shared string '%s'%s
282 (S internal) Perl maintains a reference-counted internal table of
283 strings to optimize the storage and access of hash keys and other
284 strings. This indicates someone tried to decrement the reference count
285 of a string that can no longer be found in the table.
287 =item Attempt to free temp prematurely: SV 0x%x
289 (S debugging) Mortalized values are supposed to be freed by the
290 free_tmps() routine. This indicates that something else is freeing the
291 SV before the free_tmps() routine gets a chance, which means that the
292 free_tmps() routine will be freeing an unreferenced scalar when it does
295 =item Attempt to free unreferenced glob pointers
297 (S internal) The reference counts got screwed up on symbol aliases.
299 =item Attempt to free unreferenced scalar: SV 0x%x
301 (S internal) Perl went to decrement the reference count of a scalar to
302 see if it would go to 0, and discovered that it had already gone to 0
303 earlier, and should have been freed, and in fact, probably was freed.
304 This could indicate that SvREFCNT_dec() was called too many times, or
305 that SvREFCNT_inc() was called too few times, or that the SV was
306 mortalized when it shouldn't have been, or that memory has been
309 =item Attempt to pack pointer to temporary value
311 (W pack) You tried to pass a temporary value (like the result of a
312 function, or a computed expression) to the "p" pack() template. This
313 means the result contains a pointer to a location that could become
314 invalid anytime, even before the end of the current statement. Use
315 literals or global values as arguments to the "p" pack() template to
318 =item Attempt to reload %s aborted.
320 (F) You tried to load a file with C<use> or C<require> that failed to
321 compile once already. Perl will not try to compile this file again
322 unless you delete its entry from %INC. See L<perlfunc/require> and
325 =item Attempt to set length of freed array
327 (W misc) You tried to set the length of an array which has
328 been freed. You can do this by storing a reference to the
329 scalar representing the last index of an array and later
330 assigning through that reference. For example
332 $r = do {my @a; \$#a};
335 =item Attempt to use reference as lvalue in substr
337 (W substr) You supplied a reference as the first argument to substr()
338 used as an lvalue, which is pretty strange. Perhaps you forgot to
339 dereference it first. See L<perlfunc/substr>.
341 =item Attribute "locked" is deprecated
343 (D deprecated) You have used the attributes pragma to modify the
344 "locked" attribute on a code reference. The :locked attribute is
345 obsolete, has had no effect since 5005 threads were removed, and
346 will be removed in a future release of Perl 5.
348 =item Attribute prototype(%s) discards earlier prototype attribute in same sub
350 (W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
351 example. Since each sub can only have one prototype, the earlier
352 declaration(s) are discarded while the last one is applied.
354 =item Attribute "unique" is deprecated
356 (D deprecated) You have used the attributes pragma to modify
357 the "unique" attribute on an array, hash or scalar reference.
358 The :unique attribute has had no effect since Perl 5.8.8, and
359 will be removed in a future release of Perl 5.
361 =item av_reify called on tied array
363 (S debugging) This indicates that something went wrong and Perl got I<very>
364 confused about C<@_> or C<@DB::args> being tied.
366 =item Bad arg length for %s, is %u, should be %d
368 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
369 or shmctl(). In C parlance, the correct sizes are, respectively,
370 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
371 S<sizeof(struct shmid_ds *)>.
373 =item Bad evalled substitution pattern
375 (F) You've used the C</e> switch to evaluate the replacement for a
376 substitution, but perl found a syntax error in the code to evaluate,
377 most likely an unexpected right brace '}'.
379 =item Bad filehandle: %s
381 (F) A symbol was passed to something wanting a filehandle, but the
382 symbol has no filehandle associated with it. Perhaps you didn't do an
383 open(), or did it in another package.
385 =item Bad free() ignored
387 (S malloc) An internal routine called free() on something that had never
388 been malloc()ed in the first place. Mandatory, but can be disabled by
389 setting environment variable C<PERL_BADFREE> to 0.
391 This message can be seen quite often with DB_File on systems with "hard"
392 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
393 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
397 (P) One of the internal hash routines was passed a null HV pointer.
399 =item Badly placed ()'s
401 (A) You've accidentally run your script through B<csh> instead
402 of Perl. Check the #! line, or manually feed your script into
405 =item Bad name after %s
407 (F) You started to name a symbol by using a package prefix, and then
408 didn't finish the symbol. In particular, you can't interpolate outside
417 $sym = "mypack::$var";
419 =item Bad plugin affecting keyword '%s'
421 (F) An extension using the keyword plugin mechanism violated the
424 =item Bad realloc() ignored
426 (S malloc) An internal routine called realloc() on something that
427 had never been malloc()ed in the first place. Mandatory, but can
428 be disabled by setting the environment variable C<PERL_BADFREE> to 1.
430 =item Bad symbol for array
432 (P) An internal request asked to add an array entry to something that
433 wasn't a symbol table entry.
435 =item Bad symbol for dirhandle
437 (P) An internal request asked to add a dirhandle entry to something
438 that wasn't a symbol table entry.
440 =item Bad symbol for filehandle
442 (P) An internal request asked to add a filehandle entry to something
443 that wasn't a symbol table entry.
445 =item Bad symbol for hash
447 (P) An internal request asked to add a hash entry to something that
448 wasn't a symbol table entry.
450 =item Bareword found in conditional
452 (W bareword) The compiler found a bareword where it expected a
453 conditional, which often indicates that an || or && was parsed as part
454 of the last argument of the previous construct, for example:
458 It may also indicate a misspelled constant that has been interpreted as
461 use constant TYPO => 1;
462 if (TYOP) { print "foo" }
464 The C<strict> pragma is useful in avoiding such errors.
466 =item Bareword "%s" not allowed while "strict subs" in use
468 (F) With "strict subs" in use, a bareword is only allowed as a
469 subroutine identifier, in curly brackets or to the left of the "=>"
470 symbol. Perhaps you need to predeclare a subroutine?
472 =item Bareword "%s" refers to nonexistent package
474 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
475 compiler saw no other uses of that namespace before that point. Perhaps
476 you need to predeclare a package?
478 =item BEGIN failed--compilation aborted
480 (F) An untrapped exception was raised while executing a BEGIN
481 subroutine. Compilation stops immediately and the interpreter is
484 =item BEGIN not safe after errors--compilation aborted
486 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
487 implies a C<BEGIN {}>) after one or more compilation errors had already
488 occurred. Since the intended environment for the C<BEGIN {}> could not
489 be guaranteed (due to the errors), and since subsequent code likely
490 depends on its correct operation, Perl just gave up.
492 =item \%d better written as $%d
494 (W syntax) Outside of patterns, backreferences live on as variables.
495 The use of backslashes is grandfathered on the right-hand side of a
496 substitution, but stylistically it's better to use the variable form
497 because other Perl programmers will expect it, and it works better if
498 there are more than 9 backreferences.
500 =item Binary number > 0b11111111111111111111111111111111 non-portable
502 (W portable) The binary number you specified is larger than 2**32-1
503 (4294967295) and therefore non-portable between systems. See
504 L<perlport> for more on portability concerns.
506 =item bind() on closed socket %s
508 (W closed) You tried to do a bind on a closed socket. Did you forget to
509 check the return value of your socket() call? See L<perlfunc/bind>.
511 =item binmode() on closed filehandle %s
513 (W unopened) You tried binmode() on a filehandle that was never opened.
514 Check your control flow and number of arguments.
516 =item "\b{" is deprecated; use "\b\{" or "\b[{]" instead in regex; marked
517 by S<<-- HERE> in m/%s/
519 =item "\B{" is deprecated; use "\B\{" or "\B[{]" instead in regex; marked
520 by S<<-- HERE> in m/%s/
522 (D deprecated) Use of an unescaped "{" immediately following
523 a C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
524 itself in a future release. You can either precede the brace
525 with a backslash, or enclose it in square brackets; the latter
526 is the way to go if the pattern delimiters are C<{}>.
528 =item Bit vector size > 32 non-portable
530 (W portable) Using bit vector sizes larger than 32 is non-portable.
532 =item Bizarre copy of %s
534 (P) Perl detected an attempt to copy an internal value that is not
537 =item Bizarre SvTYPE [%d]
539 (P) When starting a new thread or returning values from a thread, Perl
540 encountered an invalid data type.
542 =item Buffer overflow in prime_env_iter: %s
544 (W internal) A warning peculiar to VMS. While Perl was preparing to
545 iterate over %ENV, it encountered a logical name or symbol definition
546 which was too long, so it was truncated to the string shown.
548 =item Callback called exit
550 (F) A subroutine invoked from an external package via call_sv()
551 exited by calling exit.
553 =item %s() called too early to check prototype
555 (W prototype) You've called a function that has a prototype before the
556 parser saw a definition or declaration for it, and Perl could not check
557 that the call conforms to the prototype. You need to either add an
558 early prototype declaration for the subroutine in question, or move the
559 subroutine definition ahead of the call to get proper prototype
560 checking. Alternatively, if you are certain that you're calling the
561 function correctly, you may put an ampersand before the name to avoid
562 the warning. See L<perlsub>.
564 =item Calling POSIX::%s() is deprecated
566 (D deprecated) You called a function whose use is deprecated. See
567 the function's name in L<POSIX> for details.
569 =item Cannot compress integer in pack
571 (F) An argument to pack("w",...) was too large to compress. The BER
572 compressed integer format can only be used with positive integers, and you
573 attempted to compress Infinity or a very large number (> 1e308).
574 See L<perlfunc/pack>.
576 =item Cannot compress negative numbers in pack
578 (F) An argument to pack("w",...) was negative. The BER compressed integer
579 format can only be used with positive integers. See L<perlfunc/pack>.
581 =item Cannot convert a reference to %s to typeglob
583 (F) You manipulated Perl's symbol table directly, stored a reference
584 in it, then tried to access that symbol via conventional Perl syntax.
585 The access triggers Perl to autovivify that typeglob, but it there is
586 no legal conversion from that type of reference to a typeglob.
588 =item Cannot copy to %s
590 (P) Perl detected an attempt to copy a value to an internal type that cannot
591 be directly assigned to.
593 =item Cannot find encoding "%s"
595 (S io) You tried to apply an encoding that did not exist to a filehandle,
596 either with open() or binmode().
598 =item Cannot set tied @DB::args
600 (F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
601 is not supported. (Before this error was added, it used to crash.)
603 =item Cannot tie unreifiable array
605 (P) You somehow managed to call C<tie> on an array that does not
606 keep a reference count on its arguments and cannot be made to
607 do so. Such arrays are not even supposed to be accessible to
608 Perl code, but are only used internally.
610 =item Can only compress unsigned integers in pack
612 (F) An argument to pack("w",...) was not an integer. The BER compressed
613 integer format can only be used with positive integers, and you attempted
614 to compress something else. See L<perlfunc/pack>.
616 =item Can't bless non-reference value
618 (F) Only hard references may be blessed. This is how Perl "enforces"
619 encapsulation of objects. See L<perlobj>.
621 =item Can't "break" in a loop topicalizer
623 (F) You called C<break>, but you're in a C<foreach> block rather than
624 a C<given> block. You probably meant to use C<next> or C<last>.
626 =item Can't "break" outside a given block
628 (F) You called C<break>, but you're not inside a C<given> block.
630 =item Can't call method "%s" on an undefined value
632 (F) You used the syntax of a method call, but the slot filled by the
633 object reference or package name contains an undefined value. Something
634 like this will reproduce the error:
637 process $BADREF 1,2,3;
638 $BADREF->process(1,2,3);
640 =item Can't call method "%s" on unblessed reference
642 (F) A method call must know in what package it's supposed to run. It
643 ordinarily finds this out from the object reference you supply, but you
644 didn't supply an object reference in this case. A reference isn't an
645 object reference until it has been blessed. See L<perlobj>.
647 =item Can't call method "%s" without a package or object reference
649 (F) You used the syntax of a method call, but the slot filled by the
650 object reference or package name contains an expression that returns a
651 defined value which is neither an object reference nor a package name.
652 Something like this will reproduce the error:
655 process $BADREF 1,2,3;
656 $BADREF->process(1,2,3);
658 =item Can't call mro_isa_changed_in() on anonymous symbol table
660 (P) Perl got confused as to whether a hash was a plain hash or a
661 symbol table hash when trying to update @ISA caches.
663 =item Can't call mro_method_changed_in() on anonymous symbol table
665 (F) An XS module tried to call C<mro_method_changed_in> on a hash that was
666 not attached to the symbol table.
668 =item Can't chdir to %s
670 (F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
671 that you can chdir to, possibly because it doesn't exist.
673 =item Can't check filesystem of script "%s" for nosuid
675 (P) For some reason you can't check the filesystem of the script for
678 =item Can't coerce %s to %s in %s
680 (F) Certain types of SVs, in particular real symbol table entries
681 (typeglobs), can't be forced to stop being what they are. So you can't
691 but then $foo no longer contains a glob.
693 =item Can't "continue" outside a when block
695 (F) You called C<continue>, but you're not inside a C<when>
698 =item Can't create pipe mailbox
700 (P) An error peculiar to VMS. The process is suffering from exhausted
701 quotas or other plumbing problems.
703 =item Can't declare %s in "%s"
705 (F) Only scalar, array, and hash variables may be declared as "my", "our" or
706 "state" variables. They must have ordinary identifiers as names.
708 =item Can't "default" outside a topicalizer
710 (F) You have used a C<default> block that is neither inside a
711 C<foreach> loop nor a C<given> block. (Note that this error is
712 issued on exit from the C<default> block, so you won't get the
713 error if you use an explicit C<continue>.)
715 =item Can't do inplace edit: %s is not a regular file
717 (S inplace) You tried to use the B<-i> switch on a special file, such as
718 a file in /dev, a FIFO or an uneditable directory. The file was ignored.
720 =item Can't do inplace edit on %s: %s
722 (S inplace) The creation of the new file failed for the indicated
725 =item Can't do inplace edit without backup
727 (F) You're on a system such as MS-DOS that gets confused if you try
728 reading from a deleted (but still opened) file. You have to say
729 C<-i.bak>, or some such.
731 =item Can't do inplace edit: %s would not be unique
733 (S inplace) Your filesystem does not support filenames longer than 14
734 characters and Perl was unable to create a unique filename during
735 inplace editing with the B<-i> switch. The file was ignored.
737 =item Can't do waitpid with flags
739 (F) This machine doesn't have either waitpid() or wait4(), so only
740 waitpid() without flags is emulated.
742 =item Can't emulate -%s on #! line
744 (F) The #! line specifies a switch that doesn't make sense at this
745 point. For example, it'd be kind of silly to put a B<-x> on the #!
748 =item Can't %s %s-endian %ss on this platform
750 (F) Your platform's byte-order is neither big-endian nor little-endian,
751 or it has a very strange pointer size. Packing and unpacking big- or
752 little-endian floating point values and pointers may not be possible.
753 See L<perlfunc/pack>.
755 =item Can't exec "%s": %s
757 (W exec) A system(), exec(), or piped open call could not execute the
758 named program for the indicated reason. Typical reasons include: the
759 permissions were wrong on the file, the file wasn't found in
760 C<$ENV{PATH}>, the executable in question was compiled for another
761 architecture, or the #! line in a script points to an interpreter that
762 can't be run for similar reasons. (Or maybe your system doesn't support
767 (F) Perl was trying to execute the indicated program for you because
768 that's what the #! line said. If that's not what you wanted, you may
769 need to mention "perl" on the #! line somewhere.
771 =item Can't execute %s
773 (F) You used the B<-S> switch, but the copies of the script to execute
774 found in the PATH did not have correct permissions.
776 =item Can't find an opnumber for "%s"
778 (F) A string of a form C<CORE::word> was given to prototype(), but there
779 is no builtin with the name C<word>.
781 =item Can't find %s character property "%s"
783 (F) You used C<\p{}> or C<\P{}> but the character property by that name
784 could not be found. Maybe you misspelled the name of the property?
785 See L<perluniprops/Properties accessible through \p{} and \P{}>
786 for a complete list of available official properties.
788 =item Can't find label %s
790 (F) You said to goto a label that isn't mentioned anywhere that it's
791 possible for us to go to. See L<perlfunc/goto>.
793 =item Can't find %s on PATH
795 (F) You used the B<-S> switch, but the script to execute could not be
798 =item Can't find %s on PATH, '.' not in PATH
800 (F) You used the B<-S> switch, but the script to execute could not be
801 found in the PATH, or at least not with the correct permissions. The
802 script exists in the current directory, but PATH prohibits running it.
804 =item Can't find string terminator %s anywhere before EOF
806 (F) Perl strings can stretch over multiple lines. This message means
807 that the closing delimiter was omitted. Because bracketed quotes count
808 nesting levels, the following is missing its final parenthesis:
810 print q(The character '(' starts a side comment.);
812 If you're getting this error from a here-document, you may have
813 included unseen whitespace before or after your closing tag or there
814 may not be a linebreak after it. A good programmer's editor will have
815 a way to help you find these characters (or lack of characters). See
816 L<perlop> for the full details on here-documents.
818 =item Can't find Unicode property definition "%s"
820 (F) You may have tried to use C<\p> which means a Unicode
821 property (for example C<\p{Lu}> matches all uppercase
822 letters). If you did mean to use a Unicode property, see
823 L<perluniprops/Properties accessible through \p{} and \P{}>
824 for a complete list of available properties. If you didn't
825 mean to use a Unicode property, escape the C<\p>, either by
826 C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
831 (F) A fatal error occurred while trying to fork while opening a
834 =item Can't fork, trying again in 5 seconds
836 (W pipe) A fork in a piped open failed with EAGAIN and will be retried
839 =item Can't get filespec - stale stat buffer?
841 (S) A warning peculiar to VMS. This arises because of the difference
842 between access checks under VMS and under the Unix model Perl assumes.
843 Under VMS, access checks are done by filename, rather than by bits in
844 the stat buffer, so that ACLs and other protections can be taken into
845 account. Unfortunately, Perl assumes that the stat buffer contains all
846 the necessary information, and passes it, instead of the filespec, to
847 the access-checking routine. It will try to retrieve the filespec using
848 the device name and FID present in the stat buffer, but this works only
849 if you haven't made a subsequent call to the CRTL stat() routine,
850 because the device name is overwritten with each call. If this warning
851 appears, the name lookup failed, and the access-checking routine gave up
852 and returned FALSE, just to be conservative. (Note: The access-checking
853 routine knows about the Perl C<stat> operator and file tests, so you
854 shouldn't ever see this warning in response to a Perl command; it arises
855 only if some internal code takes stat buffers lightly.)
857 =item Can't get pipe mailbox device name
859 (P) An error peculiar to VMS. After creating a mailbox to act as a
860 pipe, Perl can't retrieve its name for later use.
862 =item Can't get SYSGEN parameter value for MAXBUF
864 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
865 mailbox buffers to be, and didn't get an answer.
867 =item Can't "goto" into the middle of a foreach loop
869 (F) A "goto" statement was executed to jump into the middle of a foreach
870 loop. You can't get there from here. See L<perlfunc/goto>.
872 =item Can't "goto" out of a pseudo block
874 (F) A "goto" statement was executed to jump out of what might look like
875 a block, except that it isn't a proper block. This usually occurs if
876 you tried to jump out of a sort() block or subroutine, which is a no-no.
877 See L<perlfunc/goto>.
879 =item Can't goto subroutine from an eval-%s
881 (F) The "goto subroutine" call can't be used to jump out of an eval
884 =item Can't goto subroutine from a sort sub (or similar callback)
886 (F) The "goto subroutine" call can't be used to jump out of the
887 comparison sub for a sort(), or from a similar callback (such
888 as the reduce() function in List::Util).
890 =item Can't goto subroutine outside a subroutine
892 (F) The deeply magical "goto subroutine" call can only replace one
893 subroutine call for another. It can't manufacture one out of whole
894 cloth. In general you should be calling it out of only an AUTOLOAD
895 routine anyway. See L<perlfunc/goto>.
897 =item Can't ignore signal CHLD, forcing to default
899 (W signal) Perl has detected that it is being run with the SIGCHLD
900 signal (sometimes known as SIGCLD) disabled. Since disabling this
901 signal will interfere with proper determination of exit status of child
902 processes, Perl has reset the signal to its default value. This
903 situation typically indicates that the parent program under which Perl
904 may be running (e.g. cron) is being very careless.
906 =item Can't kill a non-numeric process ID
908 (F) Process identifiers must be (signed) integers. It is a fatal error to
909 attempt to kill() an undefined, empty-string or otherwise non-numeric
912 =item Can't "last" outside a loop block
914 (F) A "last" statement was executed to break out of the current block,
915 except that there's this itty bitty problem called there isn't a current
916 block. Note that an "if" or "else" block doesn't count as a "loopish"
917 block, as doesn't a block given to sort(), map() or grep(). You can
918 usually double the curlies to get the same effect though, because the
919 inner curlies will be considered a block that loops once. See
922 =item Can't linearize anonymous symbol table
924 (F) Perl tried to calculate the method resolution order (MRO) of a
925 package, but failed because the package stash has no name.
927 =item Can't load '%s' for module %s
929 (F) The module you tried to load failed to load a dynamic extension.
930 This may either mean that you upgraded your version of perl to one
931 that is incompatible with your old dynamic extensions (which is known
932 to happen between major versions of perl), or (more likely) that your
933 dynamic extension was built against an older version of the library
934 that is installed on your system. You may need to rebuild your old
937 =item Can't localize lexical variable %s
939 (F) You used local on a variable name that was previously declared as a
940 lexical variable using "my" or "state". This is not allowed. If you
941 want to localize a package variable of the same name, qualify it with
944 =item Can't localize through a reference
946 (F) You said something like C<local $$ref>, which Perl can't currently
947 handle, because when it goes to restore the old value of whatever $ref
948 pointed to after the scope of the local() is finished, it can't be sure
949 that $ref will still be a reference.
951 =item Can't locate %s
953 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
954 Perl looks for the file in all the locations mentioned in @INC, unless
955 the file name included the full path to the file. Perhaps you need
956 to set the PERL5LIB or PERL5OPT environment variable to say where the
957 extra library is, or maybe the script needs to add the library name
958 to @INC. Or maybe you just misspelled the name of the file. See
959 L<perlfunc/require> and L<lib>.
961 =item Can't locate auto/%s.al in @INC
963 (F) A function (or method) was called in a package which allows
964 autoload, but there is no function to autoload. Most probable causes
965 are a misprint in a function/method name or a failure to C<AutoSplit>
966 the file, say, by doing C<make install>.
968 =item Can't locate loadable object for module %s in @INC
970 (F) The module you loaded is trying to load an external library, like
971 for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
972 unable to locate this library. See L<DynaLoader>.
974 =item Can't locate object method "%s" via package "%s"
976 (F) You called a method correctly, and it correctly indicated a package
977 functioning as a class, but that package doesn't define that particular
978 method, nor does any of its base classes. See L<perlobj>.
980 =item Can't locate package %s for @%s::ISA
982 (W syntax) The @ISA array contained the name of another package that
983 doesn't seem to exist.
985 =item Can't locate PerlIO%s
987 (F) You tried to use in open() a PerlIO layer that does not exist,
988 e.g. open(FH, ">:nosuchlayer", "somefile").
990 =item Can't make list assignment to %ENV on this system
992 (F) List assignment to %ENV is not supported on some systems, notably
995 =item Can't make loaded symbols global on this platform while loading %s
997 (S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
998 that symbols from the stated file are made available globally within the
999 process, but that functionality is not available on this platform. Whilst
1000 the module likely will still work, this may prevent the perl interpreter
1001 from loading other XS-based extensions which need to link directly to
1002 functions defined in the C or XS code in the stated file.
1004 =item Can't modify %s in %s
1006 (F) You aren't allowed to assign to the item indicated, or otherwise try
1007 to change it, such as with an auto-increment.
1009 =item Can't modify nonexistent substring
1011 (P) The internal routine that does assignment to a substr() was handed
1014 =item Can't modify non-lvalue subroutine call
1016 (F) Subroutines meant to be used in lvalue context should be declared as
1017 such. See L<perlsub/"Lvalue subroutines">.
1019 =item Can't msgrcv to read-only var
1021 (F) The target of a msgrcv must be modifiable to be used as a receive
1024 =item Can't "next" outside a loop block
1026 (F) A "next" statement was executed to reiterate the current block, but
1027 there isn't a current block. Note that an "if" or "else" block doesn't
1028 count as a "loopish" block, as doesn't a block given to sort(), map() or
1029 grep(). You can usually double the curlies to get the same effect
1030 though, because the inner curlies will be considered a block that loops
1031 once. See L<perlfunc/next>.
1035 (F) You tried to run a perl built with MAD support with
1036 the PERL_XMLDUMP environment variable set, but the file
1037 named by that variable could not be opened.
1039 =item Can't open %s: %s
1041 (S inplace) The implicit opening of a file through use of the C<< <> >>
1042 filehandle, either implicitly under the C<-n> or C<-p> command-line
1043 switches, or explicitly, failed for the indicated reason. Usually
1044 this is because you don't have read permission for a file which
1045 you named on the command line.
1047 (F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1048 your operating system's equivalent) could not be opened.
1050 =item Can't open a reference
1052 (W io) You tried to open a scalar reference for reading or writing,
1053 using the 3-arg open() syntax:
1057 but your version of perl is compiled without perlio, and this form of
1058 open is not supported.
1060 =item Can't open bidirectional pipe
1062 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1063 You can try any of several modules in the Perl library to do this, such
1064 as IPC::Open2. Alternately, direct the pipe's output to a file using
1065 ">", and then read it in under a different file handle.
1067 =item Can't open error file %s as stderr
1069 (F) An error peculiar to VMS. Perl does its own command line
1070 redirection, and couldn't open the file specified after '2>' or '2>>' on
1071 the command line for writing.
1073 =item Can't open input file %s as stdin
1075 (F) An error peculiar to VMS. Perl does its own command line
1076 redirection, and couldn't open the file specified after '<' on the
1077 command line for reading.
1079 =item Can't open output file %s as stdout
1081 (F) An error peculiar to VMS. Perl does its own command line
1082 redirection, and couldn't open the file specified after '>' or '>>' on
1083 the command line for writing.
1085 =item Can't open output pipe (name: %s)
1087 (P) An error peculiar to VMS. Perl does its own command line
1088 redirection, and couldn't open the pipe into which to send data destined
1091 =item Can't open perl script "%s": %s
1093 (F) The script you specified can't be opened for the indicated reason.
1095 If you're debugging a script that uses #!, and normally relies on the
1096 shell's $PATH search, the -S option causes perl to do that search, so
1097 you don't have to type the path or C<`which $scriptname`>.
1099 =item Can't read CRTL environ
1101 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1102 from the CRTL's internal environment array and discovered the array was
1103 missing. You need to figure out where your CRTL misplaced its environ
1104 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1107 =item Can't "redo" outside a loop block
1109 (F) A "redo" statement was executed to restart the current block, but
1110 there isn't a current block. Note that an "if" or "else" block doesn't
1111 count as a "loopish" block, as doesn't a block given to sort(), map()
1112 or grep(). You can usually double the curlies to get the same effect
1113 though, because the inner curlies will be considered a block that
1114 loops once. See L<perlfunc/redo>.
1116 =item Can't remove %s: %s, skipping file
1118 (S inplace) You requested an inplace edit without creating a backup
1119 file. Perl was unable to remove the original file to replace it with
1120 the modified file. The file was left unmodified.
1122 =item Can't rename %s to %s: %s, skipping file
1124 (S inplace) The rename done by the B<-i> switch failed for some reason,
1125 probably because you don't have write permission to the directory.
1127 =item Can't reopen input pipe (name: %s) in binary mode
1129 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1130 to reopen it to accept binary data. Alas, it failed.
1132 =item Can't reset %ENV on this system
1134 (F) You called C<reset('E')> or similar, which tried to reset
1135 all variables in the current package beginning with "E". In
1136 the main package, that includes %ENV. Resetting %ENV is not
1137 supported on some systems, notably VMS.
1139 =item Can't resolve method "%s" overloading "%s" in package "%s"
1141 (F)(P) Error resolving overloading specified by a method name (as
1142 opposed to a subroutine reference): no such method callable via the
1143 package. If the method name is C<???>, this is an internal error.
1145 =item Can't return %s from lvalue subroutine
1147 (F) Perl detected an attempt to return illegal lvalues (such as
1148 temporary or readonly values) from a subroutine used as an lvalue. This
1151 =item Can't return outside a subroutine
1153 (F) The return statement was executed in mainline code, that is, where
1154 there was no subroutine call to return out of. See L<perlsub>.
1156 =item Can't return %s to lvalue scalar context
1158 (F) You tried to return a complete array or hash from an lvalue
1159 subroutine, but you called the subroutine in a way that made Perl
1160 think you meant to return only one value. You probably meant to
1161 write parentheses around the call to the subroutine, which tell
1162 Perl that the call should be in list context.
1164 =item Can't stat script "%s"
1166 (P) For some reason you can't fstat() the script even though you have it
1167 open already. Bizarre.
1169 =item Can't take log of %g
1171 (F) For ordinary real numbers, you can't take the logarithm of a
1172 negative number or zero. There's a Math::Complex package that comes
1173 standard with Perl, though, if you really want to do that for the
1176 =item Can't take sqrt of %g
1178 (F) For ordinary real numbers, you can't take the square root of a
1179 negative number. There's a Math::Complex package that comes standard
1180 with Perl, though, if you really want to do that.
1182 =item Can't undef active subroutine
1184 (F) You can't undefine a routine that's currently running. You can,
1185 however, redefine it while it's running, and you can even undef the
1186 redefined subroutine while the old routine is running. Go figure.
1188 =item Can't upgrade %s (%d) to %d
1190 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1191 into a more specialized kind of SV. The top several SV types are so
1192 specialized, however, that they cannot be interconverted. This message
1193 indicates that such a conversion was attempted.
1195 =item Can't use '%c' after -mname
1197 (F) You tried to call perl with the B<-m> switch, but you put something
1198 other than "=" after the module name.
1200 =item Can't use anonymous symbol table for method lookup
1202 (F) The internal routine that does method lookup was handed a symbol
1203 table that doesn't have a name. Symbol tables can become anonymous
1204 for example by undefining stashes: C<undef %Some::Package::>.
1206 =item Can't use an undefined value as %s reference
1208 (F) A value used as either a hard reference or a symbolic reference must
1209 be a defined value. This helps to delurk some insidious errors.
1211 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1213 (F) Only hard references are allowed by "strict refs". Symbolic
1214 references are disallowed. See L<perlref>.
1216 =item Can't use %! because Errno.pm is not available
1218 (F) The first time the C<%!> hash is used, perl automatically loads the
1219 Errno.pm module. The Errno module is expected to tie the %! hash to
1220 provide symbolic names for C<$!> errno values.
1222 =item Can't use both '<' and '>' after type '%c' in %s
1224 (F) A type cannot be forced to have both big-endian and little-endian
1225 byte-order at the same time, so this combination of modifiers is not
1226 allowed. See L<perlfunc/pack>.
1228 =item Can't use %s for loop variable
1230 (F) Only a simple scalar variable may be used as a loop variable on a
1233 =item Can't use global %s in "%s"
1235 (F) You tried to declare a magical variable as a lexical variable. This
1236 is not allowed, because the magic can be tied to only one location
1237 (namely the global variable) and it would be incredibly confusing to
1238 have variables in your program that looked like magical variables but
1241 =item Can't use '%c' in a group with different byte-order in %s
1243 (F) You attempted to force a different byte-order on a type
1244 that is already inside a group with a byte-order modifier.
1245 For example you cannot force little-endianness on a type that
1246 is inside a big-endian group.
1248 =item Can't use "my %s" in sort comparison
1250 (F) The global variables $a and $b are reserved for sort comparisons.
1251 You mentioned $a or $b in the same line as the <=> or cmp operator,
1252 and the variable had earlier been declared as a lexical variable.
1253 Either qualify the sort variable with the package name, or rename the
1256 =item Can't use %s ref as %s ref
1258 (F) You've mixed up your reference types. You have to dereference a
1259 reference of the type needed. You can use the ref() function to
1260 test the type of the reference, if need be.
1262 =item Can't use string ("%s") as %s ref while "strict refs" in use
1264 =item Can't use string ("%s"...) as %s ref while "strict refs" in use
1266 (F) You've told Perl to dereference a string, something which
1267 C<use strict> blocks to prevent it happening accidentally. See
1268 L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1269 in a double-quoted string immediately before interpolating a variable,
1270 for example in C<"user @$twitter_id">, which says to treat the contents
1271 of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1272 symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
1274 =item Can't use subscript on %s
1276 (F) The compiler tried to interpret a bracketed expression as a
1277 subscript. But to the left of the brackets was an expression that
1278 didn't look like a hash or array reference, or anything else subscriptable.
1280 =item Can't use \%c to mean $%c in expression
1282 (W syntax) In an ordinary expression, backslash is a unary operator that
1283 creates a reference to its argument. The use of backslash to indicate a
1284 backreference to a matched substring is valid only as part of a regular
1285 expression pattern. Trying to do this in ordinary Perl code produces a
1286 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1289 =item Can't weaken a nonreference
1291 (F) You attempted to weaken something that was not a reference. Only
1292 references can be weakened.
1294 =item Can't "when" outside a topicalizer
1296 (F) You have used a when() block that is neither inside a C<foreach>
1297 loop nor a C<given> block. (Note that this error is issued on exit
1298 from the C<when> block, so you won't get the error if the match fails,
1299 or if you use an explicit C<continue>.)
1301 =item Can't x= to read-only value
1303 (F) You tried to repeat a constant value (often the undefined value)
1304 with an assignment operator, which implies modifying the value itself.
1305 Perhaps you need to copy the value to a temporary, and repeat that.
1307 =item Character following "\c" must be ASCII
1309 (F)(D deprecated, syntax) In C<\cI<X>>, I<X> must be an ASCII character.
1310 It is planned to make this fatal in all instances in Perl v5.20. In
1311 the cases where it isn't fatal, the character this evaluates to is
1312 derived by exclusive or'ing the code point of this character with 0x40.
1314 Note that non-alphabetic ASCII characters are discouraged here as well,
1315 and using non-printable ones will be deprecated starting in v5.18.
1317 =item Character in 'C' format wrapped in pack
1323 where $x is either less than 0 or more than 255; the C<"C"> format is
1324 only for encoding native operating system characters (ASCII, EBCDIC,
1325 and so on) and not for Unicode characters, so Perl behaved as if you meant
1329 If you actually want to pack Unicode codepoints, use the C<"U"> format
1332 =item Character in 'c' format wrapped in pack
1338 where $x is either less than -128 or more than 127; the C<"c"> format
1339 is only for encoding native operating system characters (ASCII, EBCDIC,
1340 and so on) and not for Unicode characters, so Perl behaved as if you meant
1342 pack("c", $x & 255);
1344 If you actually want to pack Unicode codepoints, use the C<"U"> format
1347 =item Character in '%c' format wrapped in unpack
1349 (W unpack) You tried something like
1351 unpack("H", "\x{2a1}")
1353 where the format expects to process a byte (a character with a value
1354 below 256), but a higher value was provided instead. Perl uses the
1355 value modulus 256 instead, as if you had provided:
1357 unpack("H", "\x{a1}")
1359 =item Character in 'W' format wrapped in pack
1365 where $x is either less than 0 or more than 255. However, C<U0>-mode
1366 expects all values to fall in the interval [0, 255], so Perl behaved
1369 pack("U0W", $x & 255)
1371 =item Character(s) in '%c' format wrapped in pack
1373 (W pack) You tried something like
1375 pack("u", "\x{1f3}b")
1377 where the format expects to process a sequence of bytes (character with a
1378 value below 256), but some of the characters had a higher value. Perl
1379 uses the character values modulus 256 instead, as if you had provided:
1381 pack("u", "\x{f3}b")
1383 =item Character(s) in '%c' format wrapped in unpack
1385 (W unpack) You tried something like
1387 unpack("s", "\x{1f3}b")
1389 where the format expects to process a sequence of bytes (character with a
1390 value below 256), but some of the characters had a higher value. Perl
1391 uses the character values modulus 256 instead, as if you had provided:
1393 unpack("s", "\x{f3}b")
1395 =item "\c%c" is more clearly written simply as "%s"
1397 (W syntax) The C<\cI<X>> construct is intended to be a way to specify
1398 non-printable characters. You used it for a printable one, which is better
1399 written as simply itself, perhaps preceded by a backslash for non-word
1402 =item Cloning substitution context is unimplemented
1404 (F) Creating a new thread inside the C<s///> operator is not supported.
1406 =item closedir() attempted on invalid dirhandle %s
1408 (W io) The dirhandle you tried to close is either closed or not really
1409 a dirhandle. Check your control flow.
1411 =item close() on unopened filehandle %s
1413 (W unopened) You tried to close a filehandle that was never opened.
1415 =item Closure prototype called
1417 (F) If a closure has attributes, the subroutine passed to an attribute
1418 handler is the prototype that is cloned when a new closure is created.
1419 This subroutine cannot be called.
1421 =item Code missing after '/'
1423 (F) You had a (sub-)template that ends with a '/'. There must be
1424 another template code following the slash. See L<perlfunc/pack>.
1426 =item Code point 0x%X is not Unicode, may not be portable
1428 (S non_unicode) You had a code point above the Unicode maximum
1431 Perl allows strings to contain a superset of Unicode code points, up
1432 to the limit of what is storable in an unsigned integer on your system,
1433 but these may not be accepted by other languages/systems. At one time,
1434 it was legal in some standards to have code points up to 0x7FFF_FFFF,
1435 but not higher. Code points above 0xFFFF_FFFF require larger than a
1438 =item %s: Command not found
1440 (A) You've accidentally run your script through B<csh> or another shell
1441 shell instead of Perl. Check the #! line, or manually feed your script
1442 into Perl yourself. The #! line at the top of your file could look like
1446 =item Compilation failed in require
1448 (F) Perl could not compile a file specified in a C<require> statement.
1449 Perl uses this generic message when none of the errors that it
1450 encountered were severe enough to halt compilation immediately.
1452 =item Complex regular subexpression recursion limit (%d) exceeded
1454 (W regexp) The regular expression engine uses recursion in complex
1455 situations where back-tracking is required. Recursion depth is limited
1456 to 32766, or perhaps less in architectures where the stack cannot grow
1457 arbitrarily. ("Simple" and "medium" situations are handled without
1458 recursion and are not subject to a limit.) Try shortening the string
1459 under examination; looping in Perl code (e.g. with C<while>) rather than
1460 in the regular expression engine; or rewriting the regular expression so
1461 that it is simpler or backtracks less. (See L<perlfaq2> for information
1462 on I<Mastering Regular Expressions>.)
1464 =item connect() on closed socket %s
1466 (W closed) You tried to do a connect on a closed socket. Did you forget
1467 to check the return value of your socket() call? See
1468 L<perlfunc/connect>.
1470 =item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1472 (F) The subroutine registered to handle constant overloading
1473 (see L<overload>) or a custom charnames handler (see
1474 L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1476 =item Constant(%s): $^H{%s} is not defined
1478 (F) The parser found inconsistencies while attempting to define an
1479 overloaded constant. Perhaps you forgot to load the corresponding
1480 L<overload> pragma?.
1482 =item Constant is not %s reference
1484 (F) A constant value (perhaps declared using the C<use constant> pragma)
1485 is being dereferenced, but it amounts to the wrong type of reference.
1486 The message indicates the type of reference that was expected. This
1487 usually indicates a syntax error in dereferencing the constant value.
1488 See L<perlsub/"Constant Functions"> and L<constant>.
1490 =item Constant subroutine %s redefined
1492 (W redefine)(S) You redefined a subroutine which had previously
1493 been eligible for inlining. See L<perlsub/"Constant Functions">
1494 for commentary and workarounds.
1496 =item Constant subroutine %s undefined
1498 (W misc) You undefined a subroutine which had previously been eligible
1499 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1502 =item Constant(%s) unknown
1504 (F) The parser found inconsistencies either while attempting
1505 to define an overloaded constant, or when trying to find the
1506 character name specified in the C<\N{...}> escape. Perhaps you
1507 forgot to load the corresponding L<overload> pragma?.
1509 =item Copy method did not return a reference
1511 (F) The method which overloads "=" is buggy. See
1512 L<overload/Copy Constructor>.
1514 =item &CORE::%s cannot be called directly
1516 (F) You tried to call a subroutine in the C<CORE::> namespace
1517 with C<&foo> syntax or through a reference. Some subroutines
1518 in this package cannot yet be called that way, but must be
1519 called as barewords. Something like this will work:
1521 BEGIN { *shove = \&CORE::push; }
1522 shove @array, 1,2,3; # pushes on to @array
1524 =item CORE::%s is not a keyword
1526 (F) The CORE:: namespace is reserved for Perl keywords.
1528 =item Corrupted regexp opcode %d > %d
1530 (P) This is either an error in Perl, or, if you're using
1531 one, your L<custom regular expression engine|perlreapi>. If not the
1532 latter, report the problem through the L<perlbug> utility.
1534 =item corrupted regexp pointers
1536 (P) The regular expression engine got confused by what the regular
1537 expression compiler gave it.
1539 =item corrupted regexp program
1541 (P) The regular expression engine got passed a regexp program without a
1544 =item Corrupt malloc ptr 0x%x at 0x%x
1546 (P) The malloc package that comes with Perl had an internal failure.
1548 =item Count after length/code in unpack
1550 (F) You had an unpack template indicating a counted-length string, but
1551 you have also specified an explicit size for the string. See
1555 The following are used in lib/diagnostics.t for testing two =items that
1556 share the same description. Changes here need to be propagated to there
1558 =item Deep recursion on anonymous subroutine
1560 =item Deep recursion on subroutine "%s"
1562 (W recursion) This subroutine has called itself (directly or indirectly)
1563 100 times more than it has returned. This probably indicates an
1564 infinite recursion, unless you're writing strange benchmark programs, in
1565 which case it indicates something else.
1567 This threshold can be changed from 100, by recompiling the F<perl> binary,
1568 setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1570 =item defined(@array) is deprecated
1572 (D deprecated) defined() is not usually useful on arrays because it
1573 checks for an undefined I<scalar> value. If you want to see if the
1574 array is empty, just use C<if (@array) { # not empty }> for example.
1576 =item defined(%hash) is deprecated
1578 (D deprecated) C<defined()> is not usually right on hashes and has been
1579 discouraged since 5.004.
1581 Although C<defined %hash> is false on a plain not-yet-used hash, it
1582 becomes true in several non-obvious circumstances, including iterators,
1583 weak references, stash names, even remaining true after C<undef %hash>.
1584 These things make C<defined %hash> fairly useless in practice.
1586 If a check for non-empty is what you wanted then just put it in boolean
1587 context (see L<perldata/Scalar values>):
1593 If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1594 variable exists then that's never really been reliable, and isn't
1595 a good way to enquire about the features of a package, or whether
1599 =item (?(DEFINE)....) does not allow branches in regex; marked by
1600 S<<-- HERE> in m/%s/
1602 (F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
1603 most likely cause of this error is that you left out a parenthesis inside
1604 of the C<....> part.
1606 The <-- HERE shows whereabouts in the regular expression the problem was
1609 =item %s defines neither package nor VERSION--version check failed
1611 (F) You said something like "use Module 42" but in the Module file
1612 there are neither package declarations nor a C<$VERSION>.
1614 =item delete argument is index/value array slice, use array slice
1616 (F) You used index/value array slice syntax (C<%array[...]>) as
1617 the argument to C<delete>. You probably meant C<@array[...]> with
1618 an @ symbol instead.
1620 =item delete argument is key/value hash slice, use hash slice
1622 (F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1623 C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1625 =item delete argument is not a HASH or ARRAY element or slice
1627 (F) The argument to C<delete> must be either a hash or array element,
1633 or a hash or array slice, such as:
1635 @foo[$bar, $baz, $xyzzy]
1636 @{$ref->[12]}{"susie", "queue"}
1638 =item Delimiter for here document is too long
1640 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1641 long for Perl to handle. You have to be seriously twisted to write code
1642 that triggers this error.
1644 =item Deprecated use of my() in false conditional
1646 (D deprecated) You used a declaration similar to C<my $x if 0>. There
1647 has been a long-standing bug in Perl that causes a lexical variable
1648 not to be cleared at scope exit when its declaration includes a false
1649 conditional. Some people have exploited this bug to achieve a kind of
1650 static variable. Since we intend to fix this bug, we don't want people
1651 relying on this behavior. You can achieve a similar static effect by
1652 declaring the variable in a separate block outside the function, eg
1654 sub f { my $x if 0; return $x++ }
1658 { my $x; sub f { return $x++ } }
1660 Beginning with perl 5.10.0, you can also use C<state> variables to have
1661 lexicals that are initialized only once (see L<feature>):
1663 sub f { state $x; return $x++ }
1665 =item DESTROY created new reference to dead object '%s'
1667 (F) A DESTROY() method created a new reference to the object which is
1668 just being DESTROYed. Perl is confused, and prefers to abort rather
1669 than to create a dangling reference.
1671 =item Did not produce a valid header
1675 =item %s did not return a true value
1677 (F) A required (or used) file must return a true value to indicate that
1678 it compiled correctly and ran its initialization code correctly. It's
1679 traditional to end such a file with a "1;", though any true value would
1680 do. See L<perlfunc/require>.
1682 =item (Did you mean &%s instead?)
1684 (W misc) You probably referred to an imported subroutine &FOO as $FOO or
1687 =item (Did you mean "local" instead of "our"?)
1689 (W misc) Remember that "our" does not localize the declared global
1690 variable. You have declared it again in the same lexical scope, which
1693 =item (Did you mean $ or @ instead of %?)
1695 (W) You probably said %hash{$key} when you meant $hash{$key} or
1696 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1701 (F) You passed die() an empty string (the equivalent of C<die "">) or
1702 you called it with no args and C<$@> was empty.
1704 =item Document contains no data
1708 =item %s does not define %s::VERSION--version check failed
1710 (F) You said something like "use Module 42" but the Module did not
1711 define a C<$VERSION>.
1713 =item '/' does not take a repeat count
1715 (F) You cannot put a repeat count of any kind right after the '/' code.
1716 See L<perlfunc/pack>.
1718 =item Don't know how to get file name
1720 (P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1721 somehow called on another platform. This should not happen.
1723 =item Don't know how to handle magic of type \%o
1725 (P) The internal handling of magical variables has been cursed.
1727 =item do_study: out of memory
1729 (P) This should have been caught by safemalloc() instead.
1731 =item (Do you need to predeclare %s?)
1733 (S syntax) This is an educated guess made in conjunction with the message
1734 "%s found where operator expected". It often means a subroutine or module
1735 name is being referenced that hasn't been declared yet. This may be
1736 because of ordering problems in your file, or because of a missing
1737 "sub", "package", "require", or "use" statement. If you're referencing
1738 something that isn't defined yet, you don't actually have to define the
1739 subroutine or package before the current location. You can use an empty
1740 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1742 =item dump() better written as CORE::dump()
1744 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1745 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1747 =item dump is not supported
1749 (F) Your machine doesn't support dump/undump.
1751 =item Duplicate free() ignored
1753 (S malloc) An internal routine called free() on something that had
1756 =item Duplicate modifier '%c' after '%c' in %s
1758 (W unpack) You have applied the same modifier more than once after a
1759 type in a pack template. See L<perlfunc/pack>.
1761 =item each on reference is experimental
1763 (S experimental::autoderef) C<each> with a scalar argument is experimental
1764 and may change or be removed in a future Perl version. If you want to
1765 take the risk of using this feature, simply disable this warning:
1767 no warnings "experimental::autoderef";
1769 =item elseif should be elsif
1771 (S syntax) There is no keyword "elseif" in Perl because Larry thinks
1772 it's ugly. Your code will be interpreted as an attempt to call a method
1773 named "elseif" for the class returned by the following block. This is
1774 unlikely to be what you want.
1776 =item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
1778 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1779 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1780 a regular expression without specifying the property name.
1782 =item entering effective %s failed
1784 (F) While under the C<use filetest> pragma, switching the real and
1785 effective uids or gids failed.
1787 =item %ENV is aliased to %s
1789 (F) You're running under taint mode, and the C<%ENV> variable has been
1790 aliased to another hash, so it doesn't reflect anymore the state of the
1791 program's environment. This is potentially insecure.
1793 =item Error converting file specification %s
1795 (F) An error peculiar to VMS. Because Perl may have to deal with file
1796 specifications in either VMS or Unix syntax, it converts them to a
1797 single form when it must operate on them directly. Either you've passed
1798 an invalid file specification to Perl, or you've found a case the
1799 conversion routines don't handle. Drat.
1801 =item Escape literal pattern white space under /x
1803 (D deprecated) You compiled a regular expression pattern with C</x> to
1804 ignore white space, and you used, as a literal, one of the characters
1805 that Perl plans to eventually treat as white space. The character must
1806 be escaped somehow, or it will work differently on a future Perl that
1807 does treat it as white space. The easiest way is to insert a backslash
1808 immediately before it, or to enclose it with square brackets. This
1809 change is to bring Perl into conformance with Unicode recommendations.
1810 Here are the five characters that generate this warning:
1812 U+200E LEFT-TO-RIGHT MARK,
1813 U+200F RIGHT-TO-LEFT MARK,
1814 U+2028 LINE SEPARATOR,
1816 U+2029 PARAGRAPH SEPARATOR.
1818 =item Eval-group in insecure regular expression
1820 (F) Perl detected tainted data when trying to compile a regular
1821 expression that contains the C<(?{ ... })> zero-width assertion, which
1822 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1824 =item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
1826 (F) Perl tried to compile a regular expression containing the
1827 C<(?{ ... })> zero-width assertion at run time, as it would when the
1828 pattern contains interpolated values. Since that is a security risk,
1829 it is not allowed. If you insist, you may still do this by using the
1830 C<re 'eval'> pragma or by explicitly building the pattern from an
1831 interpolated string at run time and using that in an eval(). See
1832 L<perlre/(?{ code })>.
1834 =item Eval-group not allowed, use re 'eval' in regex m/%s/
1836 (F) A regular expression contained the C<(?{ ... })> zero-width
1837 assertion, but that construct is only allowed when the C<use re 'eval'>
1838 pragma is in effect. See L<perlre/(?{ code })>.
1840 =item EVAL without pos change exceeded limit in regex; marked by
1841 S<<-- HERE> in m/%s/
1843 (F) You used a pattern that nested too many EVAL calls without consuming
1844 any text. Restructure the pattern so that text is consumed.
1846 The <-- HERE shows whereabouts in the regular expression the problem was
1849 =item Excessively long <> operator
1851 (F) The contents of a <> operator may not exceed the maximum size of a
1852 Perl identifier. If you're just trying to glob a long list of
1853 filenames, try using the glob() operator, or put the filenames into a
1854 variable and glob that.
1856 =item exec? I'm not *that* kind of operating system
1858 (F) The C<exec> function is not implemented on some systems, e.g., Symbian
1859 OS. See L<perlport>.
1861 =item Execution of %s aborted due to compilation errors.
1863 (F) The final summary message when a Perl compilation fails.
1865 =item exists argument is not a HASH or ARRAY element or a subroutine
1867 (F) The argument to C<exists> must be a hash or array element or a
1868 subroutine with an ampersand, such as:
1874 =item exists argument is not a subroutine name
1876 (F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1877 and not a subroutine call. C<exists &sub()> will generate this error.
1879 =item Exiting eval via %s
1881 (W exiting) You are exiting an eval by unconventional means, such as a
1882 goto, or a loop control statement.
1884 =item Exiting format via %s
1886 (W exiting) You are exiting a format by unconventional means, such as a
1887 goto, or a loop control statement.
1889 =item Exiting pseudo-block via %s
1891 (W exiting) You are exiting a rather special block construct (like a
1892 sort block or subroutine) by unconventional means, such as a goto, or a
1893 loop control statement. See L<perlfunc/sort>.
1895 =item Exiting subroutine via %s
1897 (W exiting) You are exiting a subroutine by unconventional means, such
1898 as a goto, or a loop control statement.
1900 =item Exiting substitution via %s
1902 (W exiting) You are exiting a substitution by unconventional means, such
1903 as a return, a goto, or a loop control statement.
1905 =item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
1907 (F) You wrote something like
1911 to denote a capturing group of the form
1912 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1913 but omitted the C<")">.
1915 =item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
1917 (F) The C<(?[...])> extended character class regular expression construct
1918 only allows character classes (including character class escapes like
1919 C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1920 containing at least one flag and exactly one C<(?[...])> construct.
1921 This allows a regular expression containing just C<(?[...])> to be
1922 interpolated. If you see this error message, then you probably
1923 have some other C<(?...)> construct inside your character class. See
1924 L<perlrecharclass/Extended Bracketed Character Classes>.
1926 =item Experimental subroutine signatures not enabled
1928 (F) To use subroutine signatures, you must first enable them:
1930 no warnings "experimental::signatures";
1931 use feature "signatures";
1932 sub foo ($left, $right) { ... }
1934 =item Experimental "%s" subs not enabled
1936 (F) To use lexical subs, you must first enable them:
1938 no warnings 'experimental::lexical_subs';
1939 use feature 'lexical_subs';
1942 =item Explicit blessing to '' (assuming package main)
1944 (W misc) You are blessing a reference to a zero length string. This has
1945 the effect of blessing the reference into the package main. This is
1946 usually not what you want. Consider providing a default target package,
1947 e.g. bless($ref, $p || 'MyPackage');
1949 =item %s: Expression syntax
1951 (A) You've accidentally run your script through B<csh> instead of Perl.
1952 Check the #! line, or manually feed your script into Perl yourself.
1954 =item %s failed--call queue aborted
1956 (F) An untrapped exception was raised while executing a UNITCHECK,
1957 CHECK, INIT, or END subroutine. Processing of the remainder of the
1958 queue of such routines has been prematurely ended.
1960 =item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
1962 (W regexp)(F) A character class range must start and end at a literal
1963 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1964 in your false range is interpreted as a literal "-". In a C<(?[...])>
1965 construct, this is an error, rather than a warning. Consider quoting
1966 the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
1967 the problem was discovered. See L<perlre>.
1969 =item Fatal VMS error (status=%d) at %s, line %d
1971 (P) An error peculiar to VMS. Something untoward happened in a VMS
1972 system service or RTL routine; Perl's exit status should provide more
1973 details. The filename in "at %s" and the line number in "line %d" tell
1974 you which section of the Perl source code is distressed.
1976 =item fcntl is not implemented
1978 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1979 PDP-11 or something?
1981 =item FETCHSIZE returned a negative value
1983 (F) A tied array claimed to have a negative number of elements, which
1986 =item Field too wide in 'u' format in pack
1988 (W pack) Each line in an uuencoded string starts with a length indicator
1989 which can't encode values above 63. So there is no point in asking for
1990 a line length bigger than that. Perl will behave as if you specified
1991 C<u63> as the format.
1993 =item Filehandle %s opened only for input
1995 (W io) You tried to write on a read-only filehandle. If you intended
1996 it to be a read-write filehandle, you needed to open it with "+<" or
1997 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1998 write the file, use ">" or ">>". See L<perlfunc/open>.
2000 =item Filehandle %s opened only for output
2002 (W io) You tried to read from a filehandle opened only for writing, If
2003 you intended it to be a read/write filehandle, you needed to open it
2004 with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2005 read from the file, use "<". See L<perlfunc/open>. Another possibility
2006 is that you attempted to open filedescriptor 0 (also known as STDIN) for
2007 output (maybe you closed STDIN earlier?).
2009 =item Filehandle %s reopened as %s only for input
2011 (W io) You opened for reading a filehandle that got the same filehandle id
2012 as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
2015 =item Filehandle STDIN reopened as %s only for output
2017 (W io) You opened for writing a filehandle that got the same filehandle id
2018 as STDIN. This occurred because you closed STDIN previously.
2020 =item Final $ should be \$ or $name
2022 (F) You must now decide whether the final $ in a string was meant to be
2023 a literal dollar sign, or was meant to introduce a variable name that
2024 happens to be missing. So you have to put either the backslash or the
2027 =item flock() on closed filehandle %s
2029 (W closed) The filehandle you're attempting to flock() got itself closed
2030 some time before now. Check your control flow. flock() operates on
2031 filehandles. Are you attempting to call flock() on a dirhandle by the
2034 =item Format not terminated
2036 (F) A format must be terminated by a line with a solitary dot. Perl got
2037 to the end of your file without finding such a line.
2039 =item Format %s redefined
2041 (W redefine) You redefined a format. To suppress this warning, say
2044 no warnings 'redefine';
2045 eval "format NAME =...";
2048 =item Found = in conditional, should be ==
2058 (or something like that).
2060 =item %s found where operator expected
2062 (S syntax) The Perl lexer knows whether to expect a term or an operator.
2063 If it sees what it knows to be a term when it was expecting to see an
2064 operator, it gives you this warning. Usually it indicates that an
2065 operator or delimiter was omitted, such as a semicolon.
2067 =item gdbm store returned %d, errno %d, key "%s"
2069 (S) A warning from the GDBM_File extension that a store failed.
2071 =item gethostent not implemented
2073 (F) Your C library apparently doesn't implement gethostent(), probably
2074 because if it did, it'd feel morally obligated to return every hostname
2077 =item get%sname() on closed socket %s
2079 (W closed) You tried to get a socket or peer socket name on a closed
2080 socket. Did you forget to check the return value of your socket() call?
2082 =item getpwnam returned invalid UIC %#o for user "%s"
2084 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2085 C<getpwnam> operator returned an invalid UIC.
2087 =item getsockopt() on closed socket %s
2089 (W closed) You tried to get a socket option on a closed socket. Did you
2090 forget to check the return value of your socket() call? See
2091 L<perlfunc/getsockopt>.
2093 =item given is experimental
2095 (S experimental::smartmatch) C<given> depends on smartmatch, which
2096 is experimental, so its behavior may change or even be removed
2097 in any future release of perl. See the explanation under
2098 L<perlsyn/Experimental Details on given and when>.
2100 =item Global symbol "%s" requires explicit package name
2102 (F) You've said "use strict" or "use strict vars", which indicates
2103 that all variables must either be lexically scoped (using "my" or "state"),
2104 declared beforehand using "our", or explicitly qualified to say
2105 which package the global variable is in (using "::").
2107 =item glob failed (%s)
2109 (S glob) Something went wrong with the external program(s) used
2110 for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2111 pattern that caused the external program to fail and exit with a
2112 nonzero status. If the message indicates that the abnormal exit
2113 resulted in a coredump, this may also mean that your csh (C shell)
2114 is broken. If so, you should change all of the csh-related variables
2115 in config.sh: If you have tcsh, make the variables refer to it as
2116 if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2117 all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
2118 think csh is missing. In either case, after editing config.sh, run
2119 C<./Configure -S> and rebuild Perl.
2121 =item Glob not terminated
2123 (F) The lexer saw a left angle bracket in a place where it was expecting
2124 a term, so it's looking for the corresponding right angle bracket, and
2125 not finding it. Chances are you left some needed parentheses out
2126 earlier in the line, and you really meant a "less than".
2128 =item gmtime(%f) too large
2130 (W overflow) You called C<gmtime> with a number that was larger than
2131 it can reliably handle and C<gmtime> probably returned the wrong
2132 date. This warning is also triggered with NaN (the special
2133 not-a-number value).
2135 =item gmtime(%f) too small
2137 (W overflow) You called C<gmtime> with a number that was smaller than
2138 it can reliably handle and C<gmtime> probably returned the wrong date.
2140 =item Got an error from DosAllocMem
2142 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2143 version of Perl, and this should not happen anyway.
2145 =item goto must have label
2147 (F) Unlike with "next" or "last", you're not allowed to goto an
2148 unspecified destination. See L<perlfunc/goto>.
2150 =item Goto undefined subroutine%s
2152 (F) You tried to call a subroutine with C<goto &sub> syntax, but
2153 the indicated subroutine hasn't been defined, or if it was, it
2154 has since been undefined.
2156 =item Group name must start with a non-digit word character in regex; marked by
2157 S<<-- HERE> in m/%s/
2159 (F) Group names must follow the rules for perl identifiers, meaning
2160 they must start with a non-digit word character. A common cause of
2161 this error is using (?&0) instead of (?0). See L<perlre>.
2163 =item ()-group starts with a count
2165 (F) A ()-group started with a count. A count is supposed to follow
2166 something: a template character or a ()-group. See L<perlfunc/pack>.
2168 =item %s had compilation errors.
2170 (F) The final summary message when a C<perl -c> fails.
2172 =item Had to create %s unexpectedly
2174 (S internal) A routine asked for a symbol from a symbol table that ought
2175 to have existed already, but for some reason it didn't, and had to be
2176 created on an emergency basis to prevent a core dump.
2178 =item Hash %%s missing the % in argument %d of %s()
2180 (D deprecated) Really old Perl let you omit the % on hash names in some
2181 spots. This is now heavily deprecated.
2183 =item %s has too many errors
2185 (F) The parser has given up trying to parse the program after 10 errors.
2186 Further error messages would likely be uninformative.
2188 =item Hexadecimal number > 0xffffffff non-portable
2190 (W portable) The hexadecimal number you specified is larger than 2**32-1
2191 (4294967295) and therefore non-portable between systems. See
2192 L<perlport> for more on portability concerns.
2194 =item Identifier too long
2196 (F) Perl limits identifiers (names for variables, functions, etc.) to
2197 about 250 characters for simple names, and somewhat more for compound
2198 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2199 of Perl are likely to eliminate these arbitrary limitations.
2201 =item Ignoring zero length \N{} in character class in regex; marked by
2202 S<<-- HERE> in m/%s/
2204 (W regexp) Named Unicode character escapes C<(\N{...})> may return a
2205 zero-length sequence. When such an escape is used in a character class
2206 its behaviour is not well defined. Check that the correct escape has
2207 been used, and the correct charname handler is in scope.
2209 =item Illegal binary digit %s
2211 (F) You used a digit other than 0 or 1 in a binary number.
2213 =item Illegal binary digit %s ignored
2215 (W digit) You may have tried to use a digit other than 0 or 1 in a
2216 binary number. Interpretation of the binary number stopped before the
2219 =item Illegal character after '_' in prototype for %s : %s
2221 (W illegalproto) An illegal character was found in a prototype
2222 declaration. The '_' in a prototype must be followed by a ';',
2223 indicating the rest of the parameters are optional, or one of '@'
2224 or '%', since those two will accept 0 or more final parameters.
2226 =item Illegal character \%o (carriage return)
2228 (F) Perl normally treats carriage returns in the program text as it
2229 would any other whitespace, which means you should never see this error
2230 when Perl was built using standard options. For some reason, your
2231 version of Perl appears to have been built without this support. Talk
2232 to your Perl administrator.
2234 =item Illegal character in prototype for %s : %s
2236 (W illegalproto) An illegal character was found in a prototype declaration.
2237 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2238 Perhaps you were trying to write a subroutine signature but didn't enable
2239 that feature first (C<use feature 'signatures'>), so your signature was
2240 instead interpreted as a bad prototype.
2242 =item Illegal declaration of anonymous subroutine
2244 (F) When using the C<sub> keyword to construct an anonymous subroutine,
2245 you must always specify a block of code. See L<perlsub>.
2247 =item Illegal declaration of subroutine %s
2249 (F) A subroutine was not declared correctly. See L<perlsub>.
2251 =item Illegal division by zero
2253 (F) You tried to divide a number by 0. Either something was wrong in
2254 your logic, or you need to put a conditional in to guard against
2257 =item Illegal hexadecimal digit %s ignored
2259 (W digit) You may have tried to use a character other than 0 - 9 or
2260 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2261 number stopped before the illegal character.
2263 =item Illegal modulus zero
2265 (F) You tried to divide a number by 0 to get the remainder. Most
2266 numbers don't take to this kindly.
2268 =item Illegal number of bits in vec
2270 (F) The number of bits in vec() (the third argument) must be a power of
2271 two from 1 to 32 (or 64, if your platform supports that).
2273 =item Illegal octal digit %s
2275 (F) You used an 8 or 9 in an octal number.
2277 =item Illegal octal digit %s ignored
2279 (W digit) You may have tried to use an 8 or 9 in an octal number.
2280 Interpretation of the octal number stopped before the 8 or 9.
2282 =item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
2284 (F) You wrote something like
2288 The C<"+"> is valid only when followed by digits, indicating a
2289 capturing group. See
2290 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2292 =item Illegal switch in PERL5OPT: -%c
2294 (X) The PERL5OPT environment variable may only be used to set the
2295 following switches: B<-[CDIMUdmtw]>.
2297 =item Ill-formed CRTL environ value "%s"
2299 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
2300 internal environ array, and encountered an element without the C<=>
2301 delimiter used to separate keys from values. The element is ignored.
2303 =item Ill-formed message in prime_env_iter: |%s|
2305 (W internal) A warning peculiar to VMS. Perl tried to read a logical
2306 name or CLI symbol definition when preparing to iterate over %ENV, and
2307 didn't see the expected delimiter between key and value, so the line was
2310 =item (in cleanup) %s
2312 (W misc) This prefix usually indicates that a DESTROY() method raised
2313 the indicated exception. Since destructors are usually called by the
2314 system at arbitrary points during execution, and often a vast number of
2315 times, the warning is issued only once for any number of failures that
2316 would otherwise result in the same message being repeated.
2318 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2319 also result in this warning. See L<perlcall/G_KEEPERR>.
2321 =item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2324 (F) There was a syntax error within the C<(?[ ])>. This can happen if the
2325 expression inside the construct was completely empty, or if there are
2326 too many or few operands for the number of operators. Perl is not smart
2327 enough to give you a more precise indication as to what is wrong.
2329 =item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2332 (F) The method resolution order (MRO) of the given class is not
2333 C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2334 documentation in L<mro> for more information.
2336 =item In EBCDIC the v-string components cannot exceed 2147483647
2338 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2339 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2340 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2342 =item Infinite recursion in regex
2344 (F) You used a pattern that references itself without consuming any input
2345 text. You should check the pattern to ensure that recursive patterns
2346 either consume text or fail.
2348 =item Initialization of state variables in list context currently forbidden
2350 (F) Currently the implementation of "state" only permits the
2351 initialization of scalar variables in scalar context. Re-write
2352 C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2353 context. Constructions such as C<state (@a) = foo()> will be
2354 supported in a future perl release.
2356 =item %%s[%s] in scalar context better written as $%s[%s]
2358 (W syntax) In scalar context, you've used an array index/value slice
2359 (indicated by %) to select a single element of an array. Generally
2360 it's better to ask for a scalar value (indicated by $). The difference
2361 is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2362 returns and when evaluating its argument, while C<%foo[&bar]> provides
2363 a list context to its subscript, which can do weird things if you're
2364 expecting only one subscript. When called in list context, it also
2365 returns the index (what C<&bar> returns) in addition to the value.
2367 =item %%s{%s} in scalar context better written as $%s{%s}
2369 (W syntax) In scalar context, you've used a hash key/value slice
2370 (indicated by %) to select a single element of a hash. Generally it's
2371 better to ask for a scalar value (indicated by $). The difference
2372 is that C<$foo{&bar}> always behaves like a scalar, both in the value
2373 it returns and when evaluating its argument, while C<@foo{&bar}> and
2374 provides a list context to its subscript, which can do weird things
2375 if you're expecting only one subscript. When called in list context,
2376 it also returns the key in addition to the value.
2378 =item Insecure dependency in %s
2380 (F) You tried to do something that the tainting mechanism didn't like.
2381 The tainting mechanism is turned on when you're running setuid or
2382 setgid, or when you specify B<-T> to turn it on explicitly. The
2383 tainting mechanism labels all data that's derived directly or indirectly
2384 from the user, who is considered to be unworthy of your trust. If any
2385 such data is used in a "dangerous" operation, you get this error. See
2386 L<perlsec> for more information.
2388 =item Insecure directory in %s
2390 (F) You can't use system(), exec(), or a piped open in a setuid or
2391 setgid script if C<$ENV{PATH}> contains a directory that is writable by
2392 the world. Also, the PATH must not contain any relative directory.
2395 =item Insecure $ENV{%s} while running %s
2397 (F) You can't use system(), exec(), or a piped open in a setuid or
2398 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
2399 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2400 supplied (or potentially supplied) by the user. The script must set
2401 the path to a known value, using trustworthy data. See L<perlsec>.
2403 =item Insecure user-defined property %s
2405 (F) Perl detected tainted data when trying to compile a regular
2406 expression that contains a call to a user-defined character property
2407 function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2408 See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2410 =item In '(?...)', splitting the initial '(?' is deprecated in regex;
2411 marked by S<<-- HERE> in m/%s/
2413 (D regexp, deprecated) The two-character sequence C<"(?"> in
2414 this context in a regular expression pattern should be an
2415 indivisible token, with nothing intervening between the C<"(">
2416 and the C<"?">, but you separated them. Due to an accident of
2417 implementation, this prohibition was not enforced, but we do
2418 plan to forbid it in a future Perl version. This message
2419 serves as giving you fair warning of this pending change.
2421 =item Integer overflow in format string for %s
2423 (F) The indexes and widths specified in the format string of C<printf()>
2424 or C<sprintf()> are too large. The numbers must not overflow the size of
2425 integers for your architecture.
2427 =item Integer overflow in %s number
2429 (S overflow) The hexadecimal, octal or binary number you have specified
2430 either as a literal or as an argument to hex() or oct() is too big for
2431 your architecture, and has been converted to a floating point number.
2432 On a 32-bit architecture the largest hexadecimal, octal or binary number
2433 representable without overflow is 0xFFFFFFFF, 037777777777, or
2434 0b11111111111111111111111111111111 respectively. Note that Perl
2435 transparently promotes all numbers to a floating point representation
2436 internally--subject to loss of precision errors in subsequent
2439 =item Integer overflow in srand
2441 (S overflow) The number you have passed to srand is too big to fit
2442 in your architecture's integer representation. The number has been
2443 replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2444 architectures). This means you may be getting less randomness than
2445 you expect, because different random seeds above the maximum will
2446 return the same sequence of random numbers.
2448 =item Integer overflow in version
2450 =item Integer overflow in version %d
2452 (W overflow) Some portion of a version initialization is too large for
2453 the size of integers for your architecture. This is not a warning
2454 because there is no rational reason for a version to try and use an
2455 element larger than typically 2**32. This is usually caused by trying
2456 to use some odd mathematical operation as a version, like 100/9.
2458 =item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
2460 (P) Something went badly wrong in the regular expression parser.
2461 The S<<-- HERE> shows whereabouts in the regular expression the problem was
2464 =item Internal inconsistency in tracking vforks
2466 (S) A warning peculiar to VMS. Perl keeps track of the number of times
2467 you've called C<fork> and C<exec>, to determine whether the current call
2468 to C<exec> should affect the current script or a subprocess (see
2469 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2470 Perl is making a guess and treating this C<exec> as a request to
2471 terminate the Perl script and execute the specified command.
2473 =item internal %<num>p might conflict with future printf extensions
2475 (S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2476 formatting follows a slightly different set of rules when called from
2477 C or XS code. Specifically, formats consisting of digits followed
2478 by "p" (e.g., "%7p") are reserved for future use. If you see this
2479 message, then an XS module tried to call that routine with one such
2482 =item Internal urp in regex; marked by S<<-- HERE> in m/%s/
2484 (P) Something went badly awry in the regular expression parser. The
2485 S<<-- HERE> shows whereabouts in the regular expression the problem was
2488 =item %s (...) interpreted as function
2490 (W syntax) You've run afoul of the rule that says that any list operator
2491 followed by parentheses turns into a function, with all the list
2492 operators arguments found inside the parentheses. See
2493 L<perlop/Terms and List Operators (Leftward)>.
2495 =item Invalid %s attribute: %s
2497 (F) The indicated attribute for a subroutine or variable was not recognized
2498 by Perl or by a user-supplied handler. See L<attributes>.
2500 =item Invalid %s attributes: %s
2502 (F) The indicated attributes for a subroutine or variable were not
2503 recognized by Perl or by a user-supplied handler. See L<attributes>.
2505 =item Invalid character in charnames alias definition; marked by
2508 (F) You tried to create a custom alias for a character name, with
2509 the C<:alias> option to C<use charnames> and the specified character in
2510 the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2512 =item Invalid \0 character in %s for %s: %s\0%s
2514 (W syscalls) Embedded \0 characters in pathnames or other system call
2515 arguments produce a warning as of 5.20. The parts after the \0 were
2516 formerly ignored by system calls.
2518 =item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
2520 (F) Only certain characters are valid for character names. The
2521 indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2523 =item Invalid conversion in %s: "%s"
2525 (W printf) Perl does not understand the given format conversion. See
2526 L<perlfunc/sprintf>.
2528 =item Invalid escape in the specified encoding in regex; marked by
2529 S<<-- HERE> in m/%s/
2531 (W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
2532 didn't correspond to a single character through the conversion
2533 from the encoding specified by the encoding pragma.
2534 The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2535 instead, except within S<C<(?[ ])>>, where it is a fatal error.
2536 The S<<-- HERE> shows whereabouts in the regular expression the
2537 escape was discovered.
2539 =item Invalid hexadecimal number in \N{U+...}
2541 =item Invalid hexadecimal number in \N{U+...} in regex; marked by
2542 S<<-- HERE> in m/%s/
2544 (F) The character constant represented by C<...> is not a valid hexadecimal
2545 number. Either it is empty, or you tried to use a character other than
2546 0 - 9 or A - F, a - f in a hexadecimal number.
2548 =item Invalid module name %s with -%c option: contains single ':'
2550 (F) The module argument to perl's B<-m> and B<-M> command-line options
2551 cannot contain single colons in the module name, but only in the
2552 arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2553 B<-MFoo:Bar=baz> is not.
2555 =item Invalid mro name: '%s'
2557 (F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2558 where C<foo> is not a valid method resolution order (MRO). Currently,
2559 the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2560 a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2562 =item Invalid negative number (%s) in chr
2564 (W utf8) You passed a negative number to C<chr>. Negative numbers are
2565 not valid characters numbers, so it return the Unicode replacement
2568 =item invalid option -D%c, use -D'' to see choices
2570 (S debugging) Perl was called with invalid debugger flags. Call perl
2571 with the B<-D> option with no flags to see the list of acceptable values.
2572 See also L<perlrun/-Dletters>.
2574 =item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
2576 (F) The range specified in a character class had a minimum character
2577 greater than the maximum character. One possibility is that you forgot the
2578 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
2579 up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
2580 problem was discovered. See L<perlre>.
2582 =item Invalid range "%s" in transliteration operator
2584 (F) The range specified in the tr/// or y/// operator had a minimum
2585 character greater than the maximum character. See L<perlop>.
2587 =item Invalid separator character %s in attribute list
2589 (F) Something other than a colon or whitespace was seen between the
2590 elements of an attribute list. If the previous attribute had a
2591 parenthesised parameter list, perhaps that list was terminated too soon.
2594 =item Invalid separator character %s in PerlIO layer specification %s
2596 (W layer) When pushing layers onto the Perl I/O system, something other
2597 than a colon or whitespace was seen between the elements of a layer list.
2598 If the previous attribute had a parenthesised parameter list, perhaps that
2599 list was terminated too soon.
2601 =item Invalid strict version format (%s)
2603 (F) A version number did not meet the "strict" criteria for versions.
2604 A "strict" version number is a positive decimal number (integer or
2605 decimal-fraction) without exponentiation or else a dotted-decimal
2606 v-string with a leading 'v' character and at least three components.
2607 The parenthesized text indicates which criteria were not met.
2608 See the L<version> module for more details on allowed version formats.
2610 =item Invalid type '%s' in %s
2612 (F) The given character is not a valid pack or unpack type.
2613 See L<perlfunc/pack>.
2615 (W) The given character is not a valid pack or unpack type but used to be
2618 =item Invalid version format (%s)
2620 (F) A version number did not meet the "lax" criteria for versions.
2621 A "lax" version number is a positive decimal number (integer or
2622 decimal-fraction) without exponentiation or else a dotted-decimal
2623 v-string. If the v-string has fewer than three components, it
2624 must have a leading 'v' character. Otherwise, the leading 'v' is
2625 optional. Both decimal and dotted-decimal versions may have a
2626 trailing "alpha" component separated by an underscore character
2627 after a fractional or dotted-decimal component. The parenthesized
2628 text indicates which criteria were not met. See the L<version> module
2629 for more details on allowed version formats.
2631 =item Invalid version object
2633 (F) The internal structure of the version object was invalid.
2634 Perhaps the internals were modified directly in some way or
2635 an arbitrary reference was blessed into the "version" class.
2637 =item In '(*VERB...)', splitting the initial '(*' is deprecated in regex;
2638 marked by S<<-- HERE> in m/%s/
2640 (D regexp, deprecated) The two-character sequence C<"(*"> in
2641 this context in a regular expression pattern should be an
2642 indivisible token, with nothing intervening between the C<"(">
2643 and the C<"*">, but you separated them. Due to an accident of
2644 implementation, this prohibition was not enforced, but we do
2645 plan to forbid it in a future Perl version. This message
2646 serves as giving you fair warning of this pending change.
2648 =item ioctl is not implemented
2650 (F) Your machine apparently doesn't implement ioctl(), which is pretty
2651 strange for a machine that supports C.
2653 =item ioctl() on unopened %s
2655 (W unopened) You tried ioctl() on a filehandle that was never opened.
2656 Check your control flow and number of arguments.
2658 =item IO layers (like '%s') unavailable
2660 (F) Your Perl has not been configured to have PerlIO, and therefore
2661 you cannot use IO layers. To have PerlIO, Perl must be configured
2664 =item IO::Socket::atmark not implemented on this architecture
2666 (F) Your machine doesn't implement the sockatmark() functionality,
2667 neither as a system call nor an ioctl call (SIOCATMARK).
2669 =item $* is no longer supported
2671 (D deprecated, syntax) The special variable C<$*>, deprecated in older
2672 perls, has been removed as of 5.10.0 and is no longer supported. In
2673 previous versions of perl the use of C<$*> enabled or disabled multi-line
2674 matching within a string.
2676 Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
2677 modifiers. You can enable C</m> for a lexical scope (even a whole file)
2678 with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
2679 then all regular expressions behaved as if they were written using C</m>.)
2681 =item $# is no longer supported
2683 (D deprecated, syntax) The special variable C<$#>, deprecated in older
2684 perls, has been removed as of 5.10.0 and is no longer supported. You
2685 should use the printf/sprintf functions instead.
2687 =item '%s' is not a code reference
2689 (W overload) The second (fourth, sixth, ...) argument of
2690 overload::constant needs to be a code reference. Either
2691 an anonymous subroutine, or a reference to a subroutine.
2693 =item '%s' is not an overloadable type
2695 (W overload) You tried to overload a constant type the overload package is
2698 =item -i used with no filenames on the command line, reading from STDIN
2700 (S inplace) The C<-i> option was passed on the command line, indicating
2701 that the script is intended to edit files in place, but no files were
2702 given. This is usually a mistake, since editing STDIN in place doesn't
2703 make sense, and can be confusing because it can make perl look like
2704 it is hanging when it is really just trying to read from STDIN. You
2705 should either pass a filename to edit, or remove C<-i> from the command
2706 line. See L<perlrun> for more details.
2708 =item Junk on end of regexp in regex m/%s/
2710 (P) The regular expression parser is confused.
2712 =item keys on reference is experimental
2714 (S experimental::autoderef) C<keys> with a scalar argument is experimental
2715 and may change or be removed in a future Perl version. If you want to
2716 take the risk of using this feature, simply disable this warning:
2718 no warnings "experimental::autoderef";
2720 =item Label not found for "last %s"
2722 (F) You named a loop to break out of, but you're not currently in a loop
2723 of that name, not even if you count where you were called from. See
2726 =item Label not found for "next %s"
2728 (F) You named a loop to continue, but you're not currently in a loop of
2729 that name, not even if you count where you were called from. See
2732 =item Label not found for "redo %s"
2734 (F) You named a loop to restart, but you're not currently in a loop of
2735 that name, not even if you count where you were called from. See
2738 =item leaving effective %s failed
2740 (F) While under the C<use filetest> pragma, switching the real and
2741 effective uids or gids failed.
2743 =item length/code after end of string in unpack
2745 (F) While unpacking, the string buffer was already used up when an unpack
2746 length/code combination tried to obtain more data. This results in
2747 an undefined value for the length. See L<perlfunc/pack>.
2749 =item length() used on %s (did you mean "scalar(%s)"?)
2751 (W syntax) You used length() on either an array or a hash when you
2752 probably wanted a count of the items.
2754 Array size can be obtained by doing:
2758 The number of items in a hash can be obtained by doing:
2762 =item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2764 (F) An extension is attempting to insert text into the current parse
2765 (using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2766 couldn't be part of the current input. This is an inherent pitfall
2767 of the stuffing mechanism, and one of the reasons to avoid it. Where
2768 it is necessary to stuff, stuffing only plain ASCII is recommended.
2770 =item Lexing code internal error (%s)
2772 (F) Lexing code supplied by an extension violated the lexer's API in a
2775 =item listen() on closed socket %s
2777 (W closed) You tried to do a listen on a closed socket. Did you forget
2778 to check the return value of your socket() call? See
2781 =item List form of piped open not implemented
2783 (F) On some platforms, notably Windows, the three-or-more-arguments
2784 form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2785 Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2787 =item localtime(%f) too large
2789 (W overflow) You called C<localtime> with a number that was larger
2790 than it can reliably handle and C<localtime> probably returned the
2791 wrong date. This warning is also triggered with NaN (the special
2792 not-a-number value).
2794 =item localtime(%f) too small
2796 (W overflow) You called C<localtime> with a number that was smaller
2797 than it can reliably handle and C<localtime> probably returned the
2800 =item Lookbehind longer than %d not implemented in regex m/%s/
2802 (F) There is currently a limit on the length of string which lookbehind can
2803 handle. This restriction may be eased in a future release.
2805 =item Lost precision when %s %f by 1
2807 (W imprecision) The value you attempted to increment or decrement by one
2808 is too large for the underlying floating point representation to store
2809 accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2810 warning because it has already switched from integers to floating point
2811 when values are too large for integers, and now even floating point is
2812 insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
2814 =item lstat() on filehandle%s
2816 (W io) You tried to do an lstat on a filehandle. What did you mean
2817 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2818 instead on the filehandle.)
2820 =item lvalue attribute %s already-defined subroutine
2822 (W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2823 attribute on or off on a Perl subroutine that is already defined
2824 does not always work properly. It may or may not do what you
2825 want, depending on what code is inside the subroutine, with exact
2826 details subject to change between Perl versions. Only do this
2827 if you really know what you are doing.
2829 =item lvalue attribute ignored after the subroutine has been defined
2831 (W misc) Using the C<:lvalue> declarative syntax to make a Perl
2832 subroutine an lvalue subroutine after it has been defined is
2833 not permitted. To make the subroutine an lvalue subroutine,
2834 add the lvalue attribute to the definition, or put the C<sub
2835 foo :lvalue;> declaration before the definition.
2837 See also L<attributes.pm|attributes>.
2839 =item Magical list constants are not supported
2841 (F) You assigned a magical array to a stash element, and then tried
2842 to use the subroutine from the same slot. You are asking Perl to do
2843 something it cannot do, details subject to change between Perl versions.
2845 =item Malformed integer in [] in pack
2847 (F) Between the brackets enclosing a numeric repeat count only digits
2848 are permitted. See L<perlfunc/pack>.
2850 =item Malformed integer in [] in unpack
2852 (F) Between the brackets enclosing a numeric repeat count only digits
2853 are permitted. See L<perlfunc/pack>.
2855 =item Malformed PERLLIB_PREFIX
2857 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2864 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2865 a builtin library search path, prefix2 is substituted. The error may
2866 appear if components are not found, or are too long. See
2867 "PERLLIB_PREFIX" in L<perlos2>.
2869 =item Malformed prototype for %s: %s
2871 (F) You tried to use a function with a malformed prototype. The
2872 syntax of function prototypes is given a brief compile-time check for
2873 obvious errors like invalid characters. A more rigorous check is run
2874 when the function is called.
2875 Perhaps the function's author was trying to write a subroutine signature
2876 but didn't enable that feature first (C<use feature 'signatures'>),
2877 so the signature was instead interpreted as a bad prototype.
2879 =item Malformed UTF-8 character (%s)
2881 (S utf8)(F) Perl detected a string that didn't comply with UTF-8
2882 encoding rules, even though it had the UTF8 flag on.
2884 One possible cause is that you set the UTF8 flag yourself for data that
2885 you thought to be in UTF-8 but it wasn't (it was for example legacy
2886 8-bit data). To guard against this, you can use Encode::decode_utf8.
2888 If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2889 sequences are handled gracefully, but if you use C<:utf8>, the flag is
2890 set without validating the data, possibly resulting in this error
2893 See also L<Encode/"Handling Malformed Data">.
2895 =item Malformed UTF-8 character immediately after '%s'
2897 (F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2898 encoding rules. The message prints out the properly encoded characters
2899 just before the first bad one. If C<utf8> warnings are enabled, a
2900 warning is generated that gives more details about the type of
2903 =item Malformed UTF-8 returned by \N{%s} immediately after '%s'
2905 (F) The charnames handler returned malformed UTF-8.
2907 =item Malformed UTF-8 string in '%c' format in unpack
2909 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2910 rules and perl was unable to guess how to make more progress.
2912 =item Malformed UTF-8 string in pack
2914 (F) You tried to pack something that didn't comply with UTF-8 encoding
2915 rules and perl was unable to guess how to make more progress.
2917 =item Malformed UTF-8 string in unpack
2919 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2920 rules and perl was unable to guess how to make more progress.
2922 =item Malformed UTF-16 surrogate
2924 (F) Perl thought it was reading UTF-16 encoded character data but while
2925 doing it Perl met a malformed Unicode surrogate.
2927 =item Mandatory parameter follows optional parameter
2929 (F) In a subroutine signature, you wrote something like "$a = undef,
2930 $b", making an earlier parameter optional and a later one mandatory.
2931 Parameters are filled from left to right, so it's impossible for the
2932 caller to omit an earlier one and pass a later one. If you want to act
2933 as if the parameters are filled from right to left, declare the rightmost
2934 optional and then shuffle the parameters around in the subroutine's body.
2936 =item Matched non-Unicode code point 0x%X against Unicode property; may
2939 (S non_unicode) Perl allows strings to contain a superset of
2940 Unicode code points; each code point may be as large as what is storable
2941 in an unsigned integer on your system, but these may not be accepted by
2942 other languages/systems. This message occurs when you matched a string
2943 containing such a code point against a regular expression pattern, and
2944 the code point was matched against a Unicode property, C<\p{...}> or
2945 C<\P{...}>. Unicode properties are only defined on Unicode code points,
2946 so the result of this match is undefined by Unicode, but Perl (starting
2947 in v5.20) treats non-Unicode code points as if they were typical
2948 unassigned Unicode ones, and matched this one accordingly. Whether a
2949 given property matches these code points or not is specified in
2950 L<perluniprops/Properties accessible through \p{} and \P{}>.
2952 This message is suppressed (unless it has been made fatal) if it is
2953 immaterial to the results of the match if the code point is Unicode or
2954 not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2955 the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2956 Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2957 every code point except these 22.)
2959 Getting this message indicates that the outcome of the match arguably
2960 should have been the opposite of what actually happened. If you think
2961 that is the case, you may wish to make the C<non_unicode> warnings
2962 category fatal; if you agree with Perl's decision, you may wish to turn
2965 See L<perlunicode/Beyond Unicode code points> for more information.
2967 =item %s matches null string many times in regex; marked by S<<-- HERE> in
2970 (W regexp) The pattern you've specified would be an infinite loop if the
2971 regular expression engine didn't specifically check for that. The S<<-- HERE>
2972 shows whereabouts in the regular expression the problem was discovered.
2975 =item Maximal count of pending signals (%u) exceeded
2977 (F) Perl aborted due to too high a number of signals pending. This
2978 usually indicates that your operating system tried to deliver signals
2979 too fast (with a very high priority), starving the perl process from
2980 resources it would need to reach a point where it can process signals
2981 safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2983 =item "%s" may clash with future reserved word
2985 (W) This warning may be due to running a perl5 script through a perl4
2986 interpreter, especially if the word that is being warned about is
2989 =item '%' may not be used in pack
2991 (F) You can't pack a string by supplying a checksum, because the
2992 checksumming process loses information, and you can't go the other way.
2993 See L<perlfunc/unpack>.
2995 =item Method for operation %s not found in package %s during blessing
2997 (F) An attempt was made to specify an entry in an overloading table that
2998 doesn't resolve to a valid subroutine. See L<overload>.
3000 =item Method %s not permitted
3004 =item Might be a runaway multi-line %s string starting on line %d
3006 (S) An advisory indicating that the previous error may have been caused
3007 by a missing delimiter on a string or pattern, because it eventually
3008 ended earlier on the current line.
3010 =item Misplaced _ in number
3012 (W syntax) An underscore (underbar) in a numeric constant did not
3013 separate two digits.
3015 =item Missing argument in %s
3017 (W uninitialized) A printf-type format required more arguments than were
3020 =item Missing argument to -%c
3022 (F) The argument to the indicated command line switch must follow
3023 immediately after the switch, without intervening spaces.
3025 =item Missing braces on \N{}
3027 =item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
3029 (F) Wrong syntax of character name literal C<\N{charname}> within
3030 double-quotish context. This can also happen when there is a space
3031 (or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3032 This modifier does not change the requirement that the brace immediately
3035 =item Missing braces on \o{}
3037 (F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3039 =item Missing comma after first argument to %s function
3041 (F) While certain functions allow you to specify a filehandle or an
3042 "indirect object" before the argument list, this ain't one of them.
3044 =item Missing command in piped open
3046 (W pipe) You used the C<open(FH, "| command")> or
3047 C<open(FH, "command |")> construction, but the command was missing or
3050 =item Missing control char name in \c
3052 (F) A double-quoted string ended with "\c", without the required control
3055 =item Missing ']' in prototype for %s : %s
3057 (W illegalproto) A grouping was started with C<[> but never closed with C<]>.
3059 =item Missing name in "%s sub"
3061 (F) The syntax for lexically scoped subroutines requires that
3062 they have a name with which they can be found.
3064 =item Missing $ on loop variable
3066 (F) Apparently you've been programming in B<csh> too much. Variables
3067 are always mentioned with the $ in Perl, unlike in the shells, where it
3068 can vary from one line to the next.
3070 =item (Missing operator before %s?)
3072 (S syntax) This is an educated guess made in conjunction with the message
3073 "%s found where operator expected". Often the missing operator is a comma.
3075 =item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
3077 (F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3079 =item Missing right brace on \N{} or unescaped left brace after \N
3081 (F) C<\N> has two meanings.
3083 The traditional one has it followed by a name enclosed in braces,
3084 meaning the character (or sequence of characters) given by that
3085 name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
3086 double-quoted strings and regular expression patterns. In patterns,
3087 it doesn't have the meaning an unescaped C<*> does.
3089 Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3090 in patterns, namely to match a non-newline character. (This is short
3091 for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3093 This can lead to some ambiguities. When C<\N> is not followed immediately
3094 by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3095 form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3096 means to match the given quantity of non-newlines (in these examples,
3097 3; and 5 or more, respectively). In all other case, where there is a
3098 C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3100 However, if there is no matching C<}>, Perl doesn't know if it was
3101 mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3102 If you meant the former, add the right brace; if you meant the latter,
3103 escape the brace with a backslash, like so: C<\N\{>
3105 =item Missing right curly or square bracket
3107 (F) The lexer counted more opening curly or square brackets than closing
3108 ones. As a general rule, you'll find it's missing near the place you
3111 =item (Missing semicolon on previous line?)
3113 (S syntax) This is an educated guess made in conjunction with the message
3114 "%s found where operator expected". Don't automatically put a semicolon on
3115 the previous line just because you saw this message.
3117 =item Modification of a read-only value attempted
3119 (F) You tried, directly or indirectly, to change the value of a
3120 constant. You didn't, of course, try "2 = 1", because the compiler
3121 catches that. But an easy way to do the same thing is:
3123 sub mod { $_[0] = 1 }
3126 Another way is to assign to a substr() that's off the end of the string.
3128 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3129 is aliased to a constant in the look I<LIST>:
3132 foreach my $n ($x, 2) {
3133 $n *= 2; # modifies the $x, but fails on attempt to
3136 =item Modification of non-creatable array value attempted, %s
3138 (F) You tried to make an array value spring into existence, and the
3139 subscript was probably negative, even counting from end of the array
3142 =item Modification of non-creatable hash value attempted, %s
3144 (P) You tried to make a hash value spring into existence, and it
3145 couldn't be created for some peculiar reason.
3147 =item Module name must be constant
3149 (F) Only a bare module name is allowed as the first argument to a "use".
3151 =item Module name required with -%c option
3153 (F) The C<-M> or C<-m> options say that Perl should load some module, but
3154 you omitted the name of the module. Consult L<perlrun> for full details
3155 about C<-M> and C<-m>.
3157 =item More than one argument to '%s' open
3159 (F) The C<open> function has been asked to open multiple files. This
3160 can happen if you are trying to open a pipe to a command that takes a
3161 list of arguments, but have forgotten to specify a piped open mode.
3162 See L<perlfunc/open> for details.
3164 =item mprotect for COW string %p %u failed with %d
3166 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3167 L<perlguts/"Copy on Write">), but a shared string buffer
3168 could not be made read-only.
3170 =item mprotect for %p %u failed with %d
3172 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3173 but an op tree could not be made read-only.
3175 =item mprotect RW for COW string %p %u failed with %d
3177 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3178 L<perlguts/"Copy on Write">), but a read-only shared string
3179 buffer could not be made mutable.
3181 =item mprotect RW for %p %u failed with %d
3183 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
3184 L<perlhacktips>), but a read-only op tree could not be made
3185 mutable before freeing the ops.
3187 =item msg%s not implemented
3189 (F) You don't have System V message IPC on your system.
3191 =item Multidimensional syntax %s not supported
3193 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3194 They're written like C<$foo[1][2][3]>, as in C.
3196 =item '/' must follow a numeric type in unpack
3198 (F) You had an unpack template that contained a '/', but this did not
3199 follow some unpack specification producing a numeric value.
3200 See L<perlfunc/pack>.
3202 =item "my sub" not yet implemented
3204 (F) Lexically scoped subroutines are not yet implemented. Don't try
3207 =item "my %s" used in sort comparison
3209 (W syntax) The package variables $a and $b are used for sort comparisons.
3210 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3211 sort comparison block, and the variable had earlier been declared as a
3212 lexical variable. Either qualify the sort variable with the package
3213 name, or rename the lexical variable.
3215 =item "my" variable %s can't be in a package
3217 (F) Lexically scoped variables aren't in a package, so it doesn't make
3218 sense to try to declare one with a package qualifier on the front. Use
3219 local() if you want to localize a package variable.
3221 =item Name "%s::%s" used only once: possible typo
3223 (W once) Typographical errors often show up as unique variable
3224 names. If you had a good reason for having a unique name, then
3225 just mention it again somehow to suppress the message. The C<our>
3226 declaration is provided for this purpose.
3228 NOTE: This warning detects symbols that have been used only once
3229 so $c, @c, %c, *c, &c, sub c{}, c(), and c (the filehandle or
3230 format) are considered the same; if a program uses $c only once
3231 but also uses any of the others it will not trigger this warning.
3232 Symbols beginning with an underscore and symbols using special
3233 identifiers (q.v. L<perldata>) are exempt from this warning.
3235 =item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
3237 (F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3238 exactly 3 digits long. This helps catch some ambiguities. If your
3239 constant is too short, add leading zeros, like
3241 (?[ [ \078 ] ]) # Syntax error!
3242 (?[ [ \0078 ] ]) # Works
3243 (?[ [ \007 8 ] ]) # Clearer
3245 The maximum number this construct can express is C<\777>. If you
3246 need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3247 two separate things, you need to separate them:
3249 (?[ [ \7776 ] ]) # Syntax error!
3250 (?[ [ \o{7776} ] ]) # One meaning
3251 (?[ [ \777 6 ] ]) # Another meaning
3252 (?[ [ \777 \006 ] ]) # Still another
3254 =item Negative '/' count in unpack
3256 (F) The length count obtained from a length/code unpack operation was
3257 negative. See L<perlfunc/pack>.
3259 =item Negative length
3261 (F) You tried to do a read/write/send/recv operation with a buffer
3262 length that is less than 0. This is difficult to imagine.
3264 =item Negative offset to vec in lvalue context
3266 (F) When C<vec> is called in an lvalue context, the second argument must be
3267 greater than or equal to zero.
3269 =item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
3271 (F) You can't quantify a quantifier without intervening parentheses.
3272 So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
3273 whereabouts in the regular expression the problem was discovered.
3275 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
3276 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
3278 =item %s never introduced
3280 (S internal) The symbol in question was declared but somehow went out of
3281 scope before it could possibly have been used.
3283 =item next::method/next::can/maybe::next::method cannot find enclosing method
3285 (F) C<next::method> needs to be called within the context of a
3286 real method in a real package, and it could not find such a context.
3289 =item \N in a character class must be a named character: \N{...} in regex;
3290 marked by S<<-- HERE> in m/%s/
3292 (F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3293 bracketed character class, for the same reason that C<.> in a character
3294 class loses its specialness: it matches almost everything, which is
3295 probably not what you want.
3297 =item \N{} in character class restricted to one character in regex; marked
3298 by S<<-- HERE> in m/%s/
3300 (F) Named Unicode character escapes C<(\N{...})> may return a
3301 multi-character sequence. Such an escape may not be used in
3302 a character class, because character classes always match one
3303 character of input. Check that the correct escape has been used,
3304 and the correct charname handler is in scope. The S<<-- HERE> shows
3305 whereabouts in the regular expression the problem was discovered.
3307 =item \N{NAME} must be resolved by the lexer in regex; marked by
3308 S<<-- HERE> in m/%s/
3310 (F) When compiling a regex pattern, an unresolved named character or
3311 sequence was encountered. This can happen in any of several ways that
3312 bypass the lexer, such as using single-quotish context, or an extra
3313 backslash in double-quotish:
3315 $re = '\N{SPACE}'; # Wrong!
3316 $re = "\\N{SPACE}"; # Wrong!
3319 Instead, use double-quotes with a single backslash:
3321 $re = "\N{SPACE}"; # ok
3324 The lexer can be bypassed as well by creating the pattern from smaller
3328 /${re}{SPACE}/; # Wrong!
3330 It's not a good idea to split a construct in the middle like this, and
3331 it doesn't work here. Instead use the solution above.
3333 Finally, the message also can happen under the C</x> regex modifier when the
3334 C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
3336 /\N {SPACE}/x; # Wrong!
3339 =item No %s allowed while running setuid
3341 (F) Certain operations are deemed to be too insecure for a setuid or
3342 setgid script to even be allowed to attempt. Generally speaking there
3343 will be another way to do what you want that is, if not secure, at least
3344 securable. See L<perlsec>.
3346 =item No code specified for -%c
3348 (F) Perl's B<-e> and B<-E> command-line options require an argument. If
3349 you want to run an empty program, pass the empty string as a separate
3350 argument or run a program consisting of a single 0 or 1:
3356 =item No comma allowed after %s
3358 (F) A list operator that has a filehandle or "indirect object" is
3359 not allowed to have a comma between that and the following arguments.
3360 Otherwise it'd be just another one of the arguments.
3362 One possible cause for this is that you expected to have imported
3363 a constant to your name space with B<use> or B<import> while no such
3364 importing took place, it may for example be that your operating
3365 system does not support that particular constant. Hopefully you did
3366 use an explicit import list for the constants you expect to see;
3367 please see L<perlfunc/use> and L<perlfunc/import>. While an
3368 explicit import list would probably have caught this error earlier
3369 it naturally does not remedy the fact that your operating system
3370 still does not support that constant. Maybe you have a typo in
3371 the constants of the symbol import list of B<use> or B<import> or in the
3372 constant name at the line where this error was triggered?
3374 =item No command into which to pipe on command line
3376 (F) An error peculiar to VMS. Perl handles its own command line
3377 redirection, and found a '|' at the end of the command line, so it
3378 doesn't know where you want to pipe the output from this command.
3380 =item No DB::DB routine defined
3382 (F) The currently executing code was compiled with the B<-d> switch, but
3383 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3384 module) didn't define a routine to be called at the beginning of each
3387 =item No dbm on this machine
3389 (P) This is counted as an internal error, because every machine should
3390 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
3392 =item No DB::sub routine defined
3394 (F) The currently executing code was compiled with the B<-d> switch, but
3395 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3396 module) didn't define a C<DB::sub> routine to be called at the beginning
3397 of each ordinary subroutine call.
3399 =item No directory specified for -I
3401 (F) The B<-I> command-line switch requires a directory name as part of the
3402 I<same> argument. Use B<-Ilib>, for instance. B<-I lib> won't work.
3404 =item No error file after 2> or 2>> on command line
3406 (F) An error peculiar to VMS. Perl handles its own command line
3407 redirection, and found a '2>' or a '2>>' on the command line, but can't
3408 find the name of the file to which to write data destined for stderr.
3410 =item No group ending character '%c' found in template
3412 (F) A pack or unpack template has an opening '(' or '[' without its
3413 matching counterpart. See L<perlfunc/pack>.
3415 =item No input file after < on command line
3417 (F) An error peculiar to VMS. Perl handles its own command line
3418 redirection, and found a '<' on the command line, but can't find the
3419 name of the file from which to read data for stdin.
3421 =item No next::method '%s' found for %s
3423 (F) C<next::method> found no further instances of this method name
3424 in the remaining packages of the MRO of this class. If you don't want
3425 it throwing an exception, use C<maybe::next::method>
3426 or C<next::can>. See L<mro>.
3428 =item Non-hex character in regex; marked by S<<-- HERE> in m/%s/
3430 (F) In a regular expression, there was a non-hexadecimal character where
3431 a hex one was expected, like
3436 =item Non-octal character in regex; marked by S<<-- HERE> in m/%s/
3438 (F) In a regular expression, there was a non-octal character where
3439 an octal one was expected, like
3443 =item Non-octal character '%c'. Resolved as "%s"
3445 (W digit) In parsing an octal numeric constant, a character was
3446 unexpectedly encountered that isn't octal. The resulting value
3449 =item "no" not allowed in expression
3451 (F) The "no" keyword is recognized and executed at compile time, and
3452 returns no useful value. See L<perlmod>.
3454 =item Non-string passed as bitmask
3456 (W misc) A number has been passed as a bitmask argument to select().
3457 Use the vec() function to construct the file descriptor bitmasks for
3458 select. See L<perlfunc/select>.
3460 =item No output file after > on command line
3462 (F) An error peculiar to VMS. Perl handles its own command line
3463 redirection, and found a lone '>' at the end of the command line, so it
3464 doesn't know where you wanted to redirect stdout.
3466 =item No output file after > or >> on command line
3468 (F) An error peculiar to VMS. Perl handles its own command line
3469 redirection, and found a '>' or a '>>' on the command line, but can't
3470 find the name of the file to which to write data destined for stdout.
3472 =item No package name allowed for variable %s in "our"
3474 (F) Fully qualified variable names are not allowed in "our"
3475 declarations, because that doesn't make much sense under existing
3476 semantics. Such syntax is reserved for future extensions.
3478 =item No Perl script found in input
3480 (F) You called C<perl -x>, but no line was found in the file beginning
3481 with #! and containing the word "perl".
3483 =item No setregid available
3485 (F) Configure didn't find anything resembling the setregid() call for
3488 =item No setreuid available
3490 (F) Configure didn't find anything resembling the setreuid() call for
3493 =item No such class %s
3495 (F) You provided a class qualifier in a "my", "our" or "state"
3496 declaration, but this class doesn't exist at this point in your program.
3498 =item No such class field "%s" in variable %s of type %s
3500 (F) You tried to access a key from a hash through the indicated typed
3501 variable but that key is not allowed by the package of the same type.
3502 The indicated package has restricted the set of allowed keys using the
3505 =item No such hook: %s
3507 (F) You specified a signal hook that was not recognized by Perl.
3508 Currently, Perl accepts C<__DIE__> and C<__WARN__> as valid signal hooks.
3510 =item No such pipe open
3512 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
3513 close a pipe which hadn't been opened. This should have been caught
3514 earlier as an attempt to close an unopened filehandle.
3516 =item No such signal: SIG%s
3518 (W signal) You specified a signal name as a subscript to %SIG that was
3519 not recognized. Say C<kill -l> in your shell to see the valid signal
3520 names on your system.
3522 =item Not a CODE reference
3524 (F) Perl was trying to evaluate a reference to a code value (that is, a
3525 subroutine), but found a reference to something else instead. You can
3526 use the ref() function to find out what kind of ref it really was. See
3529 =item Not a GLOB reference
3531 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
3532 symbol table entry that looks like C<*foo>), but found a reference to
3533 something else instead. You can use the ref() function to find out what
3534 kind of ref it really was. See L<perlref>.
3536 =item Not a HASH reference
3538 (F) Perl was trying to evaluate a reference to a hash value, but found a
3539 reference to something else instead. You can use the ref() function to
3540 find out what kind of ref it really was. See L<perlref>.
3542 =item Not an ARRAY reference
3544 (F) Perl was trying to evaluate a reference to an array value, but found
3545 a reference to something else instead. You can use the ref() function
3546 to find out what kind of ref it really was. See L<perlref>.
3548 =item Not an unblessed ARRAY reference
3550 (F) You passed a reference to a blessed array to C<push>, C<shift> or
3551 another array function. These only accept unblessed array references
3552 or arrays beginning explicitly with C<@>.
3554 =item Not a SCALAR reference
3556 (F) Perl was trying to evaluate a reference to a scalar value, but found
3557 a reference to something else instead. You can use the ref() function
3558 to find out what kind of ref it really was. See L<perlref>.
3560 =item Not a subroutine reference
3562 (F) Perl was trying to evaluate a reference to a code value (that is, a
3563 subroutine), but found a reference to something else instead. You can
3564 use the ref() function to find out what kind of ref it really was. See
3567 =item Not a subroutine reference in overload table
3569 (F) An attempt was made to specify an entry in an overloading table that
3570 doesn't somehow point to a valid subroutine. See L<overload>.
3572 =item Not enough arguments for %s
3574 (F) The function requires more arguments than you specified.
3576 =item Not enough format arguments
3578 (W syntax) A format specified more picture fields than the next line
3579 supplied. See L<perlform>.
3583 (A) You've accidentally run your script through the Bourne shell instead
3584 of Perl. Check the #! line, or manually feed your script into Perl
3587 =item (?[...]) not valid in locale in regex; marked by S<<-- HERE> in m/%s/
3589 (F) C<(?[...])> cannot be used within the scope of a C<S<use locale>> or with
3590 an C</l> regular expression modifier, as that would require deferring
3591 to run-time the calculation of what it should evaluate to, and it is
3592 regex compile-time only.
3594 =item no UTC offset information; assuming local time is UTC
3596 (S) A warning peculiar to VMS. Perl was unable to find the local
3597 timezone offset, so it's assuming that local system time is equivalent
3598 to UTC. If it's not, define the logical name
3599 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
3600 need to be added to UTC to get local time.
3602 =item Null filename used
3604 (F) You can't require the null filename, especially because on many
3605 machines that means the current directory! See L<perlfunc/require>.
3607 =item NULL OP IN RUN
3609 (S debugging) Some internal routine called run() with a null opcode
3612 =item Null picture in formline
3614 (F) The first argument to formline must be a valid format picture
3615 specification. It was found to be empty, which probably means you
3616 supplied it an uninitialized value. See L<perlform>.
3620 (P) An attempt was made to realloc NULL.
3622 =item NULL regexp argument
3624 (P) The internal pattern matching routines blew it big time.
3626 =item NULL regexp parameter
3628 (P) The internal pattern matching routines are out of their gourd.
3630 =item Number too long
3632 (F) Perl limits the representation of decimal numbers in programs to
3633 about 250 characters. You've exceeded that length. Future
3634 versions of Perl are likely to eliminate this arbitrary limitation. In
3635 the meantime, try using scientific notation (e.g. "1e6" instead of
3638 =item Number with no digits
3640 (F) Perl was looking for a number but found nothing that looked like
3641 a number. This happens, for example with C<\o{}>, with no number between
3644 =item Octal number > 037777777777 non-portable
3646 (W portable) The octal number you specified is larger than 2**32-1
3647 (4294967295) and therefore non-portable between systems. See
3648 L<perlport> for more on portability concerns.
3650 =item Odd name/value argument for subroutine
3652 (F) A subroutine using a slurpy hash parameter in its signature
3653 received an odd number of arguments to populate the hash. It requires
3654 the arguments to be paired, with the same number of keys as values.
3655 The caller of the subroutine is presumably at fault. Inconveniently,
3656 this error will be reported at the location of the subroutine, not that
3659 =item Odd number of arguments for overload::constant
3661 (W overload) The call to overload::constant contained an odd number of
3662 arguments. The arguments should come in pairs.
3664 =item Odd number of elements in anonymous hash
3666 (W misc) You specified an odd number of elements to initialize a hash,
3667 which is odd, because hashes come in key/value pairs.
3669 =item Odd number of elements in hash assignment
3671 (W misc) You specified an odd number of elements to initialize a hash,
3672 which is odd, because hashes come in key/value pairs.
3674 =item Offset outside string
3676 (F)(W layer) You tried to do a read/write/send/recv/seek operation
3677 with an offset pointing outside the buffer. This is difficult to
3678 imagine. The sole exceptions to this are that zero padding will
3679 take place when going past the end of the string when either
3680 C<sysread()>ing a file, or when seeking past the end of a scalar opened
3681 for I/O (in anticipation of future reads and to imitate the behaviour
3684 =item %s() on unopened %s
3686 (W unopened) An I/O operation was attempted on a filehandle that was
3687 never initialized. You need to do an open(), a sysopen(), or a socket()
3688 call, or call a constructor from the FileHandle package.
3690 =item -%s on unopened filehandle %s
3692 (W unopened) You tried to invoke a file test operator on a filehandle
3693 that isn't open. Check your control flow. See also L<perlfunc/-X>.
3697 (S internal) An internal warning that the grammar is screwed up.
3701 (S internal) An internal warning that the grammar is screwed up.
3703 =item Opening dirhandle %s also as a file
3705 (D io, deprecated) You used open() to associate a filehandle to
3706 a symbol (glob or scalar) that already holds a dirhandle.
3707 Although legal, this idiom might render your code confusing
3710 =item Opening filehandle %s also as a directory
3712 (D io, deprecated) You used opendir() to associate a dirhandle to
3713 a symbol (glob or scalar) that already holds a filehandle.
3714 Although legal, this idiom might render your code confusing
3717 =item Operand with no preceding operator in regex; marked by S<<-- HERE> in
3720 (F) You wrote something like
3722 (?[ \p{Digit} \p{Thai} ])
3724 There are two operands, but no operator giving how you want to combine
3727 =item Operation "%s": no method found, %s
3729 (F) An attempt was made to perform an overloaded operation for which no
3730 handler was defined. While some handlers can be autogenerated in terms
3731 of other handlers, there is no default handler for any operation, unless
3732 the C<fallback> overloading key is specified to be true. See L<overload>.
3734 =item Operation "%s" returns its argument for non-Unicode code point 0x%X
3736 (S non_unicode) You performed an operation requiring Unicode semantics
3737 on a code point that is not in Unicode, so what it should do is not
3738 defined. Perl has chosen to have it do nothing, and warn you.
3740 If the operation shown is "ToFold", it means that case-insensitive
3741 matching in a regular expression was done on the code point.
3743 If you know what you are doing you can turn off this warning by
3744 C<no warnings 'non_unicode';>.
3746 =item Operation "%s" returns its argument for UTF-16 surrogate U+%X
3748 (S surrogate) You performed an operation requiring Unicode
3749 semantics on a Unicode surrogate. Unicode frowns upon the use
3750 of surrogates for anything but storing strings in UTF-16, but
3751 semantics are (reluctantly) defined for the surrogates, and
3752 they are to do nothing for this operation. Because the use of
3753 surrogates can be dangerous, Perl warns.
3755 If the operation shown is "ToFold", it means that case-insensitive
3756 matching in a regular expression was done on the code point.
3758 If you know what you are doing you can turn off this warning by
3759 C<no warnings 'surrogate';>.
3761 =item Operator or semicolon missing before %s
3763 (S ambiguous) You used a variable or subroutine call where the parser
3764 was expecting an operator. The parser has assumed you really meant to
3765 use an operator, but this is highly likely to be incorrect. For
3766 example, if you say "*foo *foo" it will be interpreted as if you said
3769 =item Optional parameter lacks default expression
3771 (F) In a subroutine signature, you wrote something like "$a =", making a
3772 named optional parameter without a default value. A nameless optional
3773 parameter is permitted to have no default value, but a named one must
3774 have a specific default. You probably want "$a = undef".
3776 =item "our" variable %s redeclared
3778 (W misc) You seem to have already declared the same global once before
3779 in the current lexical scope.
3781 =item Out of memory!
3783 (X) The malloc() function returned 0, indicating there was insufficient
3784 remaining memory (or virtual memory) to satisfy the request. Perl has
3785 no option but to exit immediately.
3787 At least in Unix you may be able to get past this by increasing your
3788 process datasize limits: in csh/tcsh use C<limit> and
3789 C<limit datasize n> (where C<n> is the number of kilobytes) to check
3790 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
3791 and C<ulimit -d n>, respectively.
3793 =item Out of memory during %s extend
3795 (X) An attempt was made to extend an array, a list, or a string beyond
3796 the largest possible memory allocation.
3798 =item Out of memory during "large" request for %s
3800 (F) The malloc() function returned 0, indicating there was insufficient
3801 remaining memory (or virtual memory) to satisfy the request. However,
3802 the request was judged large enough (compile-time default is 64K), so a
3803 possibility to shut down by trapping this error is granted.
3805 =item Out of memory during request for %s
3807 (X)(F) The malloc() function returned 0, indicating there was
3808 insufficient remaining memory (or virtual memory) to satisfy the
3811 The request was judged to be small, so the possibility to trap it
3812 depends on the way perl was compiled. By default it is not trappable.
3813 However, if compiled for this, Perl may use the contents of C<$^M> as an
3814 emergency pool after die()ing with this message. In this case the error
3815 is trappable I<once>, and the error message will include the line and file
3816 where the failed request happened.
3818 =item Out of memory during ridiculously large request
3820 (F) You can't allocate more than 2^31+"small amount" bytes. This error
3821 is most likely to be caused by a typo in the Perl program. e.g.,
3822 C<$arr[time]> instead of C<$arr[$time]>.
3824 =item Out of memory for yacc stack
3826 (F) The yacc parser wanted to grow its stack so it could continue
3827 parsing, but realloc() wouldn't give it more memory, virtual or
3830 =item '.' outside of string in pack
3832 (F) The argument to a '.' in your template tried to move the working
3833 position to before the start of the packed string being built.
3835 =item '@' outside of string in unpack
3837 (F) You had a template that specified an absolute position outside
3838 the string being unpacked. See L<perlfunc/pack>.
3840 =item '@' outside of string with malformed UTF-8 in unpack
3842 (F) You had a template that specified an absolute position outside
3843 the string being unpacked. The string being unpacked was also invalid
3844 UTF-8. See L<perlfunc/pack>.
3846 =item overload arg '%s' is invalid
3848 (W overload) The L<overload> pragma was passed an argument it did not
3849 recognize. Did you mistype an operator?
3851 =item Overloaded dereference did not return a reference
3853 (F) An object with an overloaded dereference operator was dereferenced,
3854 but the overloaded operation did not return a reference. See
3857 =item Overloaded qr did not return a REGEXP
3859 (F) An object with a C<qr> overload was used as part of a match, but the
3860 overloaded operation didn't return a compiled regexp. See L<overload>.
3862 =item %s package attribute may clash with future reserved word: %s
3864 (W reserved) A lowercase attribute name was used that had a
3865 package-specific handler. That name might have a meaning to Perl itself
3866 some day, even though it doesn't yet. Perhaps you should use a
3867 mixed-case attribute name, instead. See L<attributes>.
3869 =item pack/unpack repeat count overflow
3871 (F) You can't specify a repeat count so large that it overflows your
3872 signed integers. See L<perlfunc/pack>.
3876 (W io) A single call to write() produced more lines than can fit on a
3877 page. See L<perlform>.
3881 (P) An internal error.
3883 =item panic: attempt to call %s in %s
3885 (P) One of the file test operators entered a code branch that calls
3886 an ACL related-function, but that function is not available on this
3887 platform. Earlier checks mean that it should not be possible to
3888 enter this branch on this platform.
3890 =item panic: child pseudo-process was never scheduled
3892 (P) A child pseudo-process in the ithreads implementation on Windows
3893 was not scheduled within the time period allowed and therefore was not
3894 able to initialize properly.
3896 =item panic: ck_grep, type=%u
3898 (P) Failed an internal consistency check trying to compile a grep.
3900 =item panic: ck_split, type=%u
3902 (P) Failed an internal consistency check trying to compile a split.
3904 =item panic: corrupt saved stack index %ld
3906 (P) The savestack was requested to restore more localized values than
3907 there are in the savestack.
3909 =item panic: del_backref
3911 (P) Failed an internal consistency check while trying to reset a weak
3916 (P) We popped the context stack to an eval context, and then discovered
3917 it wasn't an eval context.
3919 =item panic: do_subst
3921 (P) The internal pp_subst() routine was called with invalid operational
3924 =item panic: do_trans_%s
3926 (P) The internal do_trans routines were called with invalid operational
3929 =item panic: fold_constants JMPENV_PUSH returned %d
3931 (P) While attempting folding constants an exception other than an C<eval>
3936 (P) The library function frexp() failed, making printf("%f") impossible.
3938 =item panic: goto, type=%u, ix=%ld
3940 (P) We popped the context stack to a context with the specified label,
3941 and then discovered it wasn't a context we know how to do a goto in.
3943 =item panic: gp_free failed to free glob pointer
3945 (P) The internal routine used to clear a typeglob's entries tried
3946 repeatedly, but each time something re-created entries in the glob.
3947 Most likely the glob contains an object with a reference back to
3948 the glob and a destructor that adds a new object to the glob.
3950 =item panic: INTERPCASEMOD, %s
3952 (P) The lexer got into a bad state at a case modifier.
3954 =item panic: INTERPCONCAT, %s
3956 (P) The lexer got into a bad state parsing a string with brackets.
3958 =item panic: kid popen errno read
3960 (F) A forked child returned an incomprehensible message about its errno.
3962 =item panic: last, type=%u
3964 (P) We popped the context stack to a block context, and then discovered
3965 it wasn't a block context.
3967 =item panic: leave_scope clearsv
3969 (P) A writable lexical variable became read-only somehow within the
3972 =item panic: leave_scope inconsistency %u
3974 (P) The savestack probably got out of sync. At least, there was an
3975 invalid enum on the top of it.
3977 =item panic: magic_killbackrefs
3979 (P) Failed an internal consistency check while trying to reset all weak
3980 references to an object.
3982 =item panic: malloc, %s
3984 (P) Something requested a negative number of bytes of malloc.
3986 =item panic: memory wrap
3988 (P) Something tried to allocate either more memory than possible or a
3991 =item panic: pad_alloc, %p!=%p
3993 (P) The compiler got confused about which scratch pad it was allocating
3994 and freeing temporaries and lexicals from.
3996 =item panic: pad_free curpad, %p!=%p
3998 (P) The compiler got confused about which scratch pad it was allocating
3999 and freeing temporaries and lexicals from.
4001 =item panic: pad_free po
4003 (P) An invalid scratch pad offset was detected internally.
4005 =item panic: pad_reset curpad, %p!=%p
4007 (P) The compiler got confused about which scratch pad it was allocating
4008 and freeing temporaries and lexicals from.
4010 =item panic: pad_sv po
4012 (P) An invalid scratch pad offset was detected internally.
4014 =item panic: pad_swipe curpad, %p!=%p
4016 (P) The compiler got confused about which scratch pad it was allocating
4017 and freeing temporaries and lexicals from.
4019 =item panic: pad_swipe po
4021 (P) An invalid scratch pad offset was detected internally.
4023 =item panic: pp_iter, type=%u
4025 (P) The foreach iterator got called in a non-loop context frame.
4027 =item panic: pp_match%s
4029 (P) The internal pp_match() routine was called with invalid operational
4032 =item panic: pp_split, pm=%p, s=%p
4034 (P) Something terrible went wrong in setting up for the split.
4036 =item panic: realloc, %s
4038 (P) Something requested a negative number of bytes of realloc.
4040 =item panic: reference miscount on nsv in sv_replace() (%d != 1)
4042 (P) The internal sv_replace() function was handed a new SV with a
4043 reference count other than 1.
4045 =item panic: restartop in %s
4047 (P) Some internal routine requested a goto (or something like it), and
4048 didn't supply the destination.
4050 =item panic: return, type=%u
4052 (P) We popped the context stack to a subroutine or eval context, and
4053 then discovered it wasn't a subroutine or eval context.
4055 =item panic: scan_num, %s
4057 (P) scan_num() got called on something that wasn't a number.
4059 =item panic: Sequence (?{...}): no code block found in regex m/%s/
4061 (P) While compiling a pattern that has embedded (?{}) or (??{}) code
4062 blocks, perl couldn't locate the code block that should have already been
4063 seen and compiled by perl before control passed to the regex compiler.
4065 =item panic: strxfrm() gets absurd - a => %u, ab => %u
4067 (P) The interpreter's sanity check of the C function strxfrm() failed.
4068 In your current locale the returned transformation of the string "ab"
4069 is shorter than that of the string "a", which makes no sense.
4071 =item panic: sv_chop %s
4073 (P) The sv_chop() routine was passed a position that is not within the
4074 scalar's string buffer.
4076 =item panic: sv_insert, midend=%p, bigend=%p
4078 (P) The sv_insert() routine was told to remove more string than there
4081 =item panic: top_env
4083 (P) The compiler attempted to do a goto, or something weird like that.
4085 =item panic: unimplemented op %s (#%d) called
4087 (P) The compiler is screwed up and attempted to use an op that isn't
4088 permitted at run time.
4090 =item panic: utf16_to_utf8: odd bytelen
4092 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
4093 to even) byte length.
4095 =item panic: utf16_to_utf8_reversed: odd bytelen
4097 (P) Something tried to call utf16_to_utf8_reversed with an odd (as opposed
4098 to even) byte length.
4100 =item panic: yylex, %s
4102 (P) The lexer got into a bad state while processing a case modifier.
4104 =item Parentheses missing around "%s" list
4106 (W parenthesis) You said something like
4112 my ($foo, $bar) = @_;
4114 Remember that "my", "our", "local" and "state" bind tighter than comma.
4116 =item Parsing code internal error (%s)
4118 (F) Parsing code supplied by an extension violated the parser's API in
4121 =item Passing malformed UTF-8 to "%s" is deprecated
4123 (D deprecated, utf8) This message indicates a bug either in the Perl
4124 core or in XS code. Such code was trying to find out if a character,
4125 allegedly stored internally encoded as UTF-8, was of a given type, such
4126 as being punctuation or a digit. But the character was not encoded in
4127 legal UTF-8. The C<%s> is replaced by a string that can be used by
4128 knowledgeable people to determine what the type being checked against
4129 was. If C<utf8> warnings are enabled, a further message is raised,
4130 giving details of the malformation.
4132 =item Pattern subroutine nesting without pos change exceeded limit in regex
4134 (F) You used a pattern that uses too many nested subpattern calls without
4135 consuming any text. Restructure the pattern so text is consumed before
4136 the nesting limit is exceeded.
4138 =item C<-p> destination: %s
4140 (F) An error occurred during the implicit output invoked by the C<-p>
4141 command-line switch. (This output goes to STDOUT unless you've
4142 redirected it with select().)
4144 =item (perhaps you forgot to load "%s"?)
4146 (F) This is an educated guess made in conjunction with the message
4147 "Can't locate object method \"%s\" via package \"%s\"". It often means
4148 that a method requires a package that has not been loaded.
4150 =item Perl folding rules are not up-to-date for 0x%X; please use the perlbug
4151 utility to report; in regex; marked by S<<-- HERE> in m/%s/
4153 (S regexp) You used a regular expression with case-insensitive matching,
4154 and there is a bug in Perl in which the built-in regular expression
4155 folding rules are not accurate. This may lead to incorrect results.
4156 Please report this as a bug using the L<perlbug> utility.
4158 =item Perl_my_%s() not available
4160 (F) Your platform has very uncommon byte-order and integer size,
4161 so it was not possible to set up some or all fixed-width byte-order
4162 conversion functions. This is only a problem when you're using the
4163 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
4165 =item Perl %s required (did you mean %s?)--this is only %s, stopped
4167 (F) The code you are trying to run has asked for a newer version of
4168 Perl than you are running. Perhaps C<use 5.10> was written instead
4169 of C<use 5.010> or C<use v5.10>. Without the leading C<v>, the number is
4170 interpreted as a decimal, with every three digits after the
4171 decimal point representing a part of the version number. So 5.10
4172 is equivalent to v5.100.
4174 =item Perl %s required--this is only %s, stopped
4176 (F) The module in question uses features of a version of Perl more
4177 recent than the currently running version. How long has it been since
4178 you upgraded, anyway? See L<perlfunc/require>.
4180 =item PERL_SH_DIR too long
4182 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
4183 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
4185 =item PERL_SIGNALS illegal: "%s"
4187 (X) See L<perlrun/PERL_SIGNALS> for legal values.
4189 =item Perls since %s too modern--this is %s, stopped
4191 (F) The code you are trying to run claims it will not run
4192 on the version of Perl you are using because it is too new.
4193 Maybe the code needs to be updated, or maybe it is simply
4194 wrong and the version check should just be removed.
4196 =item perl: warning: Non hex character in '$ENV{PERL_HASH_SEED}', seed only partially set
4198 (S) PERL_HASH_SEED should match /^\s*(?:0x)?[0-9a-fA-F]+\s*\z/ but it
4199 contained a non hex character. This could mean you are not using the
4200 hash seed you think you are.
4202 =item perl: warning: Setting locale failed.
4204 (S) The whole warning message will look something like:
4206 perl: warning: Setting locale failed.
4207 perl: warning: Please check that your locale settings:
4210 are supported and installed on your system.
4211 perl: warning: Falling back to the standard locale ("C").
4213 Exactly what were the failed locale settings varies. In the above the
4214 settings were that the LC_ALL was "En_US" and the LANG had no value.
4215 This error means that Perl detected that you and/or your operating
4216 system supplier and/or system administrator have set up the so-called
4217 locale system but Perl could not use those settings. This was not
4218 dead serious, fortunately: there is a "default locale" called "C" that
4219 Perl can and will use, and the script will be run. Before you really
4220 fix the problem, however, you will get the same error message each
4221 time you run Perl. How to really fix the problem can be found in
4222 L<perllocale> section B<LOCALE PROBLEMS>.
4224 =item perl: warning: strange setting in '$ENV{PERL_PERTURB_KEYS}': '%s'
4226 (S) Perl was run with the environment variable PERL_PERTURB_KEYS defined
4227 but containing an unexpected value. The legal values of this setting
4230 Numeric | String | Result
4231 --------+---------------+-----------------------------------------
4232 0 | NO | Disables key traversal randomization
4233 1 | RANDOM | Enables full key traversal randomization
4234 2 | DETERMINISTIC | Enables repeatable key traversal
4237 Both numeric and string values are accepted, but note that string values are
4238 case sensitive. The default for this setting is "RANDOM" or 1.
4240 =item pid %x not a child
4242 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
4243 process which isn't a subprocess of the current process. While this is
4244 fine from VMS' perspective, it's probably not what you intended.
4246 =item 'P' must have an explicit size in unpack
4248 (F) The unpack format P must have an explicit size, not "*".
4250 =item pop on reference is experimental
4252 (S experimental::autoderef) C<pop> with a scalar argument is experimental
4253 and may change or be removed in a future Perl version. If you want to
4254 take the risk of using this feature, simply disable this warning:
4256 no warnings "experimental::autoderef";
4258 =item POSIX class [:%s:] unknown in regex; marked by S<< <-- HERE in m/%s/ >>
4260 (F) The class in the character class [: :] syntax is unknown. The S<<-- HERE>
4261 shows whereabouts in the regular expression the problem was discovered.
4262 Note that the POSIX character classes do B<not> have the C<is> prefix
4263 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
4264 not C<isprint>. See L<perlre>.
4266 =item POSIX getpgrp can't take an argument
4268 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
4269 the BSD version, which takes a pid.
4271 =item POSIX syntax [%c %c] belongs inside character classes in regex; marked by
4272 S<<-- HERE> in m/%s/
4274 (W regexp) The character class constructs [: :], [= =], and [. .] go
4275 I<inside> character classes, the [] are part of the construct, for example:
4276 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
4277 implemented; they are simply placeholders for future extensions and
4278 will cause fatal errors. The S<<-- HERE> shows whereabouts in the regular
4279 expression the problem was discovered. See L<perlre>.
4281 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by
4282 S<<-- HERE> in m/%s/
4284 (F) Within regular expression character classes ([]) the syntax beginning
4285 with "[." and ending with ".]" is reserved for future extensions. If you
4286 need to represent those character sequences inside a regular expression
4287 character class, just quote the square brackets with the backslash: "\[."
4288 and ".\]". The S<<-- HERE> shows whereabouts in the regular expression the
4289 problem was discovered. See L<perlre>.
4291 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by
4292 S<<-- HERE> in m/%s/
4294 (F) Within regular expression character classes ([]) the syntax beginning
4295 with "[=" and ending with "=]" is reserved for future extensions. If you
4296 need to represent those character sequences inside a regular expression
4297 character class, just quote the square brackets with the backslash: "\[="
4298 and "=\]". The S<<-- HERE> shows whereabouts in the regular expression the
4299 problem was discovered. See L<perlre>.
4301 =item Possible attempt to put comments in qw() list
4303 (W qw) qw() lists contain items separated by whitespace; as with literal
4304 strings, comment characters are not ignored, but are instead treated as
4305 literal data. (You may have used different delimiters than the
4306 parentheses shown here; braces are also frequently used.)
4308 You probably wrote something like this:
4315 when you should have written this:
4322 If you really want comments, build your list the
4323 old-fashioned way, with quotes and commas:
4327 'b', # another comment
4330 =item Possible attempt to separate words with commas
4332 (W qw) qw() lists contain items separated by whitespace; therefore
4333 commas aren't needed to separate the items. (You may have used
4334 different delimiters than the parentheses shown here; braces are also
4337 You probably wrote something like this:
4341 which puts literal commas into some of the list items. Write it without
4342 commas if you don't want them to appear in your data:
4346 =item Possible memory corruption: %s overflowed 3rd argument
4348 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
4349 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
4350 end of the buffer just in case. This sentinel byte got clobbered, and
4351 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
4353 =item Possible precedence issue with control flow operator
4355 (W syntax) There is a possible problem with the mixing of a control
4356 flow operator (e.g. C<return>) and a low-precedence operator like
4359 sub { return $a or $b; }
4363 sub { (return $a) or $b; }
4365 Which is effectively just:
4369 Either use parentheses or the high-precedence variant of the operator.
4371 Note this may be also triggered for constructs like:
4375 =item Possible precedence problem on bitwise %c operator
4377 (W precedence) Your program uses a bitwise logical operator in conjunction
4378 with a numeric comparison operator, like this :
4380 if ($x & $y == 0) { ... }
4382 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
4383 higher precedence of C<==>. This is probably not what you want. (If you
4384 really meant to write this, disable the warning, or, better, put the
4385 parentheses explicitly and write C<$x & ($y == 0)>).
4387 =item Possible unintended interpolation of $\ in regex
4389 (W ambiguous) You said something like C<m/$\/> in a regex.
4390 The regex C<m/foo$\s+bar/m> translates to: match the word 'foo', the output
4391 record separator (see L<perlvar/$\>) and the letter 's' (one time or more)
4392 followed by the word 'bar'.
4394 If this is what you intended then you can silence the warning by using
4395 C<m/${\}/> (for example: C<m/foo${\}s+bar/>).
4397 If instead you intended to match the word 'foo' at the end of the line
4398 followed by whitespace and the word 'bar' on the next line then you can use
4399 C<m/$(?)\/> (for example: C<m/foo$(?)\s+bar/>).
4401 =item Possible unintended interpolation of %s in string
4403 (W ambiguous) You said something like '@foo' in a double-quoted string
4404 but there was no array C<@foo> in scope at the time. If you wanted a
4405 literal @foo, then write it as \@foo; otherwise find out what happened
4406 to the array you apparently lost track of.
4408 =item Postfix dereference is experimental
4410 (S experimental::postderef) This warning is emitted if you use
4411 the experimental postfix dereference syntax. Simply suppress the
4412 warning if you want to use the feature, but know that in doing
4413 so you are taking the risk of using an experimental feature which
4414 may change or be removed in a future Perl version:
4416 no warnings "experimental::postderef";
4417 use feature "postderef", "postderef_qq";
4423 =item Precedence problem: open %s should be open(%s)
4425 (S precedence) The old irregular construct
4429 is now misinterpreted as
4433 because of the strict regularization of Perl 5's grammar into unary and
4434 list operators. (The old open was a little of both.) You must put
4435 parentheses around the filehandle, or use the new "or" operator instead
4438 =item Premature end of script headers
4442 =item printf() on closed filehandle %s
4444 (W closed) The filehandle you're writing to got itself closed sometime
4445 before now. Check your control flow.
4447 =item print() on closed filehandle %s
4449 (W closed) The filehandle you're printing on got itself closed sometime
4450 before now. Check your control flow.
4452 =item Process terminated by SIG%s
4454 (W) This is a standard message issued by OS/2 applications, while *nix
4455 applications die in silence. It is considered a feature of the OS/2
4456 port. One can easily disable this by appropriate sighandlers, see
4457 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
4460 =item Property '%s' is unknown in regex; marked by S<<-- HERE> in m/%s/
4462 (F) The named property which you specified via C<\p> or C<\P> is not one
4463 known to Perl. Perhaps you misspelled the name? See
4464 L<perluniprops/Properties accessible through \p{} and \P{}>
4465 for a complete list of available official
4466 properties. If it is a L<user-defined property|perlunicode/User-Defined Character Properties>
4467 it must have been defined by the time the regular expression is
4470 =item Prototype after '%c' for %s : %s
4472 (W illegalproto) A character follows % or @ in a prototype. This is
4473 useless, since % and @ gobble the rest of the subroutine arguments.
4475 =item Prototype mismatch: %s vs %s
4477 (S prototype) The subroutine being declared or defined had previously been
4478 declared or defined with a different function prototype.
4480 =item Prototype not terminated
4482 (F) You've omitted the closing parenthesis in a function prototype
4485 =item Prototype '%s' overridden by attribute 'prototype(%s)' in %s
4487 (W prototype) A prototype was declared in both the parentheses after
4488 the sub name and via the prototype attribute. The prototype in
4489 parentheses is useless, since it will be replaced by the prototype
4490 from the attribute before it's ever used.
4492 =item \p{} uses Unicode rules, not locale rules
4494 (W) You compiled a regular expression that contained a Unicode property
4495 match (C<\p> or C<\P>), but the regular expression is also being told to
4496 use the run-time locale, not Unicode. Instead, use a POSIX character
4497 class, which should know about the locale's rules.
4498 (See L<perlrecharclass/POSIX Character Classes>.)
4500 Even if the run-time locale is ISO 8859-1 (Latin1), which is a subset of
4501 Unicode, some properties will give results that are not valid for that
4504 Here are a couple of examples to help you see what's going on. If the
4505 locale is ISO 8859-7, the character at code point 0xD7 is the "GREEK
4506 CAPITAL LETTER CHI". But in Unicode that code point means the
4507 "MULTIPLICATION SIGN" instead, and C<\p> always uses the Unicode
4508 meaning. That means that C<\p{Alpha}> won't match, but C<[[:alpha:]]>
4509 should. Only in the Latin1 locale are all the characters in the same
4510 positions as they are in Unicode. But, even here, some properties give
4511 incorrect results. An example is C<\p{Changes_When_Uppercased}> which
4512 is true for "LATIN SMALL LETTER Y WITH DIAERESIS", but since the upper
4513 case of that character is not in Latin1, in that locale it doesn't
4514 change when upper cased.
4516 =item push on reference is experimental
4518 (S experimental::autoderef) C<push> with a scalar argument is experimental
4519 and may change or be removed in a future Perl version. If you want to
4520 take the risk of using this feature, simply disable this warning:
4522 no warnings "experimental::autoderef";
4524 =item Quantifier follows nothing in regex; marked by S<< <-- HERE in m/%s/ >>
4526 (F) You started a regular expression with a quantifier. Backslash it if
4527 you meant it literally. The S<<-- HERE> shows whereabouts in the regular
4528 expression the problem was discovered. See L<perlre>.
4530 =item Quantifier in {,} bigger than %d in regex; marked by S<<-- HERE> in
4533 (F) There is currently a limit to the size of the min and max values of
4534 the {min,max} construct. The S<<-- HERE> shows whereabouts in the regular
4535 expression the problem was discovered. See L<perlre>.
4537 =item Quantifier {n,m} with n > m can't match in regex
4539 =item Quantifier {n,m} with n > m can't match in regex; marked by
4540 S<<-- HERE> in m/%s/
4542 (W regexp) Minima should be less than or equal to maxima. If you really
4543 want your regexp to match something 0 times, just put {0}.
4545 =item Quantifier unexpected on zero-length expression in regex; marked by <--
4548 (W regexp) You applied a regular expression quantifier in a place where
4549 it makes no sense, such as on a zero-width assertion. Try putting the
4550 quantifier inside the assertion instead. For example, the way to match
4551 "abc" provided that it is followed by three repetitions of "xyz" is
4552 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
4554 The <-- HERE shows whereabouts in the regular expression the problem was
4557 =item Range iterator outside integer range
4559 (F) One (or both) of the numeric arguments to the range operator ".."
4560 are outside the range which can be represented by integers internally.
4561 One possible workaround is to force Perl to use magical string increment
4562 by prepending "0" to your numbers.
4564 =item readdir() attempted on invalid dirhandle %s
4566 (W io) The dirhandle you're reading from is either closed or not really
4567 a dirhandle. Check your control flow.
4569 =item readline() on closed filehandle %s
4571 (W closed) The filehandle you're reading from got itself closed sometime
4572 before now. Check your control flow.
4574 =item read() on closed filehandle %s
4576 (W closed) You tried to read from a closed filehandle.
4578 =item read() on unopened filehandle %s
4580 (W unopened) You tried to read from a filehandle that was never opened.
4582 =item Reallocation too large: %x
4584 (F) You can't allocate more than 64K on an MS-DOS machine.
4586 =item realloc() of freed memory ignored
4588 (S malloc) An internal routine called realloc() on something that had
4591 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
4593 (S debugging) You can't use the B<-D> option unless the code to produce
4594 the desired output is compiled into Perl, which entails some overhead,
4595 which is why it's currently left out of your copy.
4597 =item Recursive call to Perl_load_module in PerlIO_find_layer
4599 (P) It is currently not permitted to load modules when creating
4600 a filehandle inside an %INC hook. This can happen with C<open my
4601 $fh, '<', \$scalar>, which implicitly loads PerlIO::scalar. Try
4602 loading PerlIO::scalar explicitly first.
4604 =item Recursive inheritance detected in package '%s'
4606 (F) While calculating the method resolution order (MRO) of a package, Perl
4607 believes it found an infinite loop in the C<@ISA> hierarchy. This is a
4608 crude check that bails out after 100 levels of C<@ISA> depth.
4610 =item refcnt_dec: fd %d%s
4612 =item refcnt: fd %d%s
4614 =item refcnt_inc: fd %d%s
4616 (P) Perl's I/O implementation failed an internal consistency check. If
4617 you see this message, something is very wrong.
4619 =item Reference found where even-sized list expected
4621 (W misc) You gave a single reference where Perl was expecting a list
4622 with an even number of elements (for assignment to a hash). This
4623 usually means that you used the anon hash constructor when you meant
4624 to use parens. In any case, a hash requires key/value B<pairs>.
4626 %hash = { one => 1, two => 2, }; # WRONG
4627 %hash = [ qw/ an anon array / ]; # WRONG
4628 %hash = ( one => 1, two => 2, ); # right
4629 %hash = qw( one 1 two 2 ); # also fine
4631 =item Reference is already weak
4633 (W misc) You have attempted to weaken a reference that is already weak.
4634 Doing so has no effect.
4636 =item Reference to invalid group 0 in regex; marked by S<<-- HERE> in m/%s/
4638 (F) You used C<\g0> or similar in a regular expression. You may refer
4639 to capturing parentheses only with strictly positive integers
4640 (normal backreferences) or with strictly negative integers (relative
4641 backreferences). Using 0 does not make sense.
4643 =item Reference to nonexistent group in regex; marked by S<<-- HERE> in
4646 (F) You used something like C<\7> in your regular expression, but there are
4647 not at least seven sets of capturing parentheses in the expression. If
4648 you wanted to have the character with ordinal 7 inserted into the regular
4649 expression, prepend zeroes to make it three digits long: C<\007>
4651 The <-- HERE shows whereabouts in the regular expression the problem was
4654 =item Reference to nonexistent named group in regex; marked by S<<-- HERE>
4657 (F) You used something like C<\k'NAME'> or C<< \k<NAME> >> in your regular
4658 expression, but there is no corresponding named capturing parentheses
4659 such as C<(?'NAME'...)> or C<< (?<NAME>...) >>. Check if the name has been
4660 spelled correctly both in the backreference and the declaration.
4662 The <-- HERE shows whereabouts in the regular expression the problem was
4665 =item Reference to nonexistent or unclosed group in regex; marked by
4666 S<<-- HERE> in m/%s/
4668 (F) You used something like C<\g{-7}> in your regular expression, but there
4669 are not at least seven sets of closed capturing parentheses in the
4670 expression before where the C<\g{-7}> was located.
4672 The <-- HERE shows whereabouts in the regular expression the problem was
4675 =item regexp memory corruption
4677 (P) The regular expression engine got confused by what the regular
4678 expression compiler gave it.
4680 =item Regexp modifier "/%c" may appear a maximum of twice
4682 =item Regexp modifier "%c" may appear a maximum of twice in regex; marked
4683 by S<<-- HERE> in m/%s/
4685 (F) The regular expression pattern had too many occurrences
4686 of the specified modifier. Remove the extraneous ones.
4688 =item Regexp modifier "%c" may not appear after the "-" in regex; marked by <--
4691 (F) Turning off the given modifier has the side effect of turning on
4692 another one. Perl currently doesn't allow this. Reword the regular
4693 expression to use the modifier you want to turn on (and place it before
4694 the minus), instead of the one you want to turn off.
4696 =item Regexp modifier "/%c" may not appear twice
4698 =item Regexp modifier "%c" may not appear twice in regex; marked by <--
4701 (F) The regular expression pattern had too many occurrences
4702 of the specified modifier. Remove the extraneous ones.
4704 =item Regexp modifiers "/%c" and "/%c" are mutually exclusive
4706 =item Regexp modifiers "%c" and "%c" are mutually exclusive in regex;
4707 marked by S<<-- HERE> in m/%s/
4709 (F) The regular expression pattern had more than one of these
4710 mutually exclusive modifiers. Retain only the modifier that is
4711 supposed to be there.
4713 =item Regexp out of space in regex m/%s/
4715 (P) A "can't happen" error, because safemalloc() should have caught it
4718 =item Repeated format line will never terminate (~~ and @#)
4720 (F) Your format contains the ~~ repeat-until-blank sequence and a
4721 numeric field that will never go blank so that the repetition never
4722 terminates. You might use ^# instead. See L<perlform>.
4724 =item Replacement list is longer than search list
4726 (W misc) You have used a replacement list that is longer than the
4727 search list. So the additional elements in the replacement list
4730 =item '%s' resolved to '\o{%s}%d'
4732 (W misc, regexp) You wrote something like C<\08>, or C<\179> in a
4733 double-quotish string. All but the last digit is treated as a single
4734 character, specified in octal. The last digit is the next character in
4735 the string. To tell Perl that this is indeed what you want, you can use
4736 the C<\o{ }> syntax, or use exactly three digits to specify the octal
4739 =item Reversed %s= operator
4741 (W syntax) You wrote your assignment operator backwards. The = must
4742 always come last, to avoid ambiguity with subsequent unary operators.
4744 =item rewinddir() attempted on invalid dirhandle %s
4746 (W io) The dirhandle you tried to do a rewinddir() on is either closed
4747 or not really a dirhandle. Check your control flow.
4749 =item Scalars leaked: %d
4751 (S internal) Something went wrong in Perl's internal bookkeeping
4752 of scalars: not all scalar variables were deallocated by the time
4753 Perl exited. What this usually indicates is a memory leak, which
4754 is of course bad, especially if the Perl program is intended to be
4757 =item Scalar value @%s[%s] better written as $%s[%s]
4759 (W syntax) You've used an array slice (indicated by @) to select a
4760 single element of an array. Generally it's better to ask for a scalar
4761 value (indicated by $). The difference is that C<$foo[&bar]> always
4762 behaves like a scalar, both when assigning to it and when evaluating its
4763 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
4764 and provides a list context to its subscript, which can do weird things
4765 if you're expecting only one subscript.
4767 On the other hand, if you were actually hoping to treat the array
4768 element as a list, you need to look into how references work, because
4769 Perl will not magically convert between scalars and lists for you. See
4772 =item Scalar value @%s{%s} better written as $%s{%s}
4774 (W syntax) You've used a hash slice (indicated by @) to select a single
4775 element of a hash. Generally it's better to ask for a scalar value
4776 (indicated by $). The difference is that C<$foo{&bar}> always behaves
4777 like a scalar, both when assigning to it and when evaluating its
4778 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
4779 and provides a list context to its subscript, which can do weird things
4780 if you're expecting only one subscript.
4782 On the other hand, if you were actually hoping to treat the hash element
4783 as a list, you need to look into how references work, because Perl will
4784 not magically convert between scalars and lists for you. See
4787 =item Search pattern not terminated
4789 (F) The lexer couldn't find the final delimiter of a // or m{}
4790 construct. Remember that bracketing delimiters count nesting level.
4791 Missing the leading C<$> from a variable C<$m> may cause this error.
4793 Note that since Perl 5.10.0 a // can also be the I<defined-or>
4794 construct, not just the empty search pattern. Therefore code written
4795 in Perl 5.10.0 or later that uses the // as the I<defined-or> can be
4796 misparsed by pre-5.10.0 Perls as a non-terminated search pattern.
4798 =item Search pattern not terminated or ternary operator parsed as search pattern
4800 (F) The lexer couldn't find the final delimiter of a C<?PATTERN?>
4803 The question mark is also used as part of the ternary operator (as in
4804 C<foo ? 0 : 1>) leading to some ambiguous constructions being wrongly
4805 parsed. One way to disambiguate the parsing is to put parentheses around
4806 the conditional expression, i.e. C<(foo) ? 0 : 1>.
4808 =item seekdir() attempted on invalid dirhandle %s
4810 (W io) The dirhandle you are doing a seekdir() on is either closed or not
4811 really a dirhandle. Check your control flow.
4813 =item %sseek() on unopened filehandle
4815 (W unopened) You tried to use the seek() or sysseek() function on a
4816 filehandle that was either never opened or has since been closed.
4818 =item select not implemented
4820 (F) This machine doesn't implement the select() system call.
4822 =item Self-ties of arrays and hashes are not supported
4824 (F) Self-ties are of arrays and hashes are not supported in
4825 the current implementation.
4827 =item Semicolon seems to be missing
4829 (W semicolon) A nearby syntax error was probably caused by a missing
4830 semicolon, or possibly some other missing operator, such as a comma.
4832 =item semi-panic: attempt to dup freed string
4834 (S internal) The internal newSVsv() routine was called to duplicate a
4835 scalar that had previously been marked as free.
4837 =item sem%s not implemented
4839 (F) You don't have System V semaphore IPC on your system.
4841 =item send() on closed socket %s
4843 (W closed) The socket you're sending to got itself closed sometime
4844 before now. Check your control flow.
4846 =item Sequence (? incomplete in regex; marked by S<<-- HERE> in m/%s/
4848 (F) A regular expression ended with an incomplete extension (?. The
4849 S<<-- HERE> shows whereabouts in the regular expression the problem was
4850 discovered. See L<perlre>.
4852 =item Sequence (?%c...) not implemented in regex; marked by S<<-- HERE> in
4855 (F) A proposed regular expression extension has the character reserved
4856 but has not yet been written. The S<<-- HERE> shows whereabouts in the
4857 regular expression the problem was discovered. See L<perlre>.
4859 =item Sequence (?%s...) not recognized in regex; marked by S<<-- HERE> in
4862 (F) You used a regular expression extension that doesn't make sense.
4863 The S<<-- HERE> shows whereabouts in the regular expression the problem was
4864 discovered. This may happen when using the C<(?^...)> construct to tell
4865 Perl to use the default regular expression modifiers, and you
4866 redundantly specify a default modifier. For other
4867 causes, see L<perlre>.
4869 =item Sequence (?#... not terminated in regex m/%s/
4871 (F) A regular expression comment must be terminated by a closing
4872 parenthesis. Embedded parentheses aren't allowed. See
4875 =item Sequence (?&... not terminated in regex; marked by S<<-- HERE> in
4878 (F) A named reference of the form C<(?&...)> was missing the final
4879 closing parenthesis after the name. The S<<-- HERE> shows whereabouts
4880 in the regular expression the problem was discovered.
4882 =item Sequence (?%c... not terminated in regex; marked by S<<-- HERE>
4885 (F) A named group of the form C<(?'...')> or C<< (?<...>) >> was missing the final
4886 closing quote or angle bracket. The S<<-- HERE> shows whereabouts in the
4887 regular expression the problem was discovered.
4889 =item Sequence (?(%c... not terminated in regex; marked by S<<-- HERE>
4892 (F) A named reference of the form C<(?('...')...)> or C<< (?(<...>)...) >> was
4893 missing the final closing quote or angle bracket after the name. The
4894 S<<-- HERE> shows whereabouts in the regular expression the problem was
4897 =item Sequence \%s... not terminated in regex; marked by S<<-- HERE> in
4900 (F) The regular expression expects a mandatory argument following the escape
4901 sequence and this has been omitted or incorrectly written.
4903 =item Sequence (?{...}) not terminated with ')'
4905 (F) The end of the perl code contained within the {...} must be
4906 followed immediately by a ')'.
4908 =item Sequence ?P=... not terminated in regex; marked by S<<-- HERE> in
4911 (F) A named reference of the form C<(?P=...)> was missing the final
4912 closing parenthesis after the name. The S<<-- HERE> shows whereabouts
4913 in the regular expression the problem was discovered.
4915 =item Sequence (?R) not terminated in regex m/%s/
4917 (F) An C<(?R)> or C<(?0)> sequence in a regular expression was missing the
4920 =item Server error (a.k.a. "500 Server error")
4922 (A) This is the error message generally seen in a browser window
4923 when trying to run a CGI program (including SSI) over the web. The
4924 actual error text varies widely from server to server. The most
4925 frequently-seen variants are "500 Server error", "Method (something)
4926 not permitted", "Document contains no data", "Premature end of script
4927 headers", and "Did not produce a valid header".
4929 B<This is a CGI error, not a Perl error>.
4931 You need to make sure your script is executable, is accessible by
4932 the user CGI is running the script under (which is probably not the
4933 user account you tested it under), does not rely on any environment
4934 variables (like PATH) from the user it isn't running under, and isn't
4935 in a location where the CGI server can't find it, basically, more or
4936 less. Please see the following for more information:
4938 http://www.perl.org/CGI_MetaFAQ.html
4939 http://www.htmlhelp.org/faq/cgifaq.html
4940 http://www.w3.org/Security/Faq/
4942 You should also look at L<perlfaq9>.
4944 =item setegid() not implemented
4946 (F) You tried to assign to C<$)>, and your operating system doesn't
4947 support the setegid() system call (or equivalent), or at least Configure
4950 =item seteuid() not implemented
4952 (F) You tried to assign to C<< $> >>, and your operating system doesn't
4953 support the seteuid() system call (or equivalent), or at least Configure
4956 =item setpgrp can't take arguments
4958 (F) Your system has the setpgrp() from BSD 4.2, which takes no
4959 arguments, unlike POSIX setpgid(), which takes a process ID and process
4962 =item setrgid() not implemented
4964 (F) You tried to assign to C<$(>, and your operating system doesn't
4965 support the setrgid() system call (or equivalent), or at least Configure
4968 =item setruid() not implemented
4970 (F) You tried to assign to C<$<>, and your operating system doesn't
4971 support the setruid() system call (or equivalent), or at least Configure
4974 =item setsockopt() on closed socket %s
4976 (W closed) You tried to set a socket option on a closed socket. Did you
4977 forget to check the return value of your socket() call? See
4978 L<perlfunc/setsockopt>.
4980 =item Setting $/ to a reference to %s as a form of slurp is deprecated, treating as undef
4982 (W deprecated) You assigned a reference to a scalar to C<$/> where the
4983 referenced item is not a positive integer. In older perls this B<appeared>
4984 to work the same as setting it to C<undef> but was in fact internally
4985 different, less efficient and with very bad luck could have resulted in
4986 your file being split by a stringified form of the reference.
4988 In Perl 5.20.0 this was changed so that it would be B<exactly> the same as
4989 setting C<$/> to undef, with the exception that this warning would be
4992 You are recommended to change your code to set C<$/> to C<undef> explicitly
4993 if you wish to slurp the file. In future versions of Perl assigning
4994 a reference to will throw a fatal error.
4996 =item Setting $/ to %s reference is forbidden
4998 (F) You tried to assign a reference to a non integer to C<$/>. In older
4999 Perls this would have behaved similarly to setting it to a reference to
5000 a positive integer, where the integer was the address of the reference.
5001 As of Perl 5.20.0 this is a fatal error, to allow future versions of Perl
5002 to use non-integer refs for more interesting purposes.
5004 =item shift on reference is experimental
5006 (S experimental::autoderef) C<shift> with a scalar argument is experimental
5007 and may change or be removed in a future Perl version. If you want to
5008 take the risk of using this feature, simply disable this warning:
5010 no warnings "experimental::autoderef";
5012 =item shm%s not implemented
5014 (F) You don't have System V shared memory IPC on your system.
5016 =item !=~ should be !~
5018 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
5019 interpreted as the != (numeric not equal) and ~ (1's complement)
5020 operators: probably not what you intended.
5022 =item <> should be quotes
5024 (F) You wrote C<< require <file> >> when you should have written
5027 =item /%s/ should probably be written as "%s"
5029 (W syntax) You have used a pattern where Perl expected to find a string,
5030 as in the first argument to C<join>. Perl will treat the true or false
5031 result of matching the pattern against $_ as the string, which is
5032 probably not what you had in mind.
5034 =item shutdown() on closed socket %s
5036 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
5039 =item SIG%s handler "%s" not defined
5041 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
5042 Perhaps you put it into the wrong package?
5044 =item Slab leaked from cv %p
5046 (S) If you see this message, then something is seriously wrong with the
5047 internal bookkeeping of op trees. An op tree needed to be freed after
5048 a compilation error, but could not be found, so it was leaked instead.
5050 =item sleep(%u) too large
5052 (W overflow) You called C<sleep> with a number that was larger than
5053 it can reliably handle and C<sleep> probably slept for less time than
5056 =item Slurpy parameter not last
5058 (F) In a subroutine signature, you put something after a slurpy (array or
5059 hash) parameter. The slurpy parameter takes all the available arguments,
5060 so there can't be any left to fill later parameters.
5062 =item Smart matching a non-overloaded object breaks encapsulation
5064 (F) You should not use the C<~~> operator on an object that does not
5065 overload it: Perl refuses to use the object's underlying structure
5066 for the smart match.
5068 =item Smartmatch is experimental
5070 (S experimental::smartmatch) This warning is emitted if you
5071 use the smartmatch (C<~~>) operator. This is currently an experimental
5072 feature, and its details are subject to change in future releases of
5073 Perl. Particularly, its current behavior is noticed for being
5074 unnecessarily complex and unintuitive, and is very likely to be
5077 =item sort is now a reserved word
5079 (F) An ancient error message that almost nobody ever runs into anymore.
5080 But before sort was a keyword, people sometimes used it as a filehandle.
5082 =item Sort subroutine didn't return single value
5084 (F) A sort comparison subroutine written in XS must return exactly one
5085 item. See L<perlfunc/sort>.
5087 =item Source filters apply only to byte streams
5089 (F) You tried to activate a source filter (usually by loading a
5090 source filter module) within a string passed to C<eval>. This is
5091 not permitted under the C<unicode_eval> feature. Consider using
5092 C<evalbytes> instead. See L<feature>.
5094 =item splice() offset past end of array
5096 (W misc) You attempted to specify an offset that was past the end of
5097 the array passed to splice(). Splicing will instead commence at the
5098 end of the array, rather than past it. If this isn't what you want,
5099 try explicitly pre-extending the array by assigning $#array = $offset.
5100 See L<perlfunc/splice>.
5102 =item splice on reference is experimental
5104 (S experimental::autoderef) C<splice> with a scalar argument
5105 is experimental and may change or be removed in a future
5106 Perl version. If you want to take the risk of using this
5107 feature, simply disable this warning:
5109 no warnings "experimental::autoderef";
5113 (P) The split was looping infinitely. (Obviously, a split shouldn't
5114 iterate more times than there are characters of input, which is what
5115 happened.) See L<perlfunc/split>.
5117 =item Statement unlikely to be reached
5119 (W exec) You did an exec() with some statement after it other than a
5120 die(). This is almost always an error, because exec() never returns
5121 unless there was a failure. You probably wanted to use system()
5122 instead, which does return. To suppress this warning, put the exec() in
5125 =item "state %s" used in sort comparison
5127 (W syntax) The package variables $a and $b are used for sort comparisons.
5128 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
5129 sort comparison block, and the variable had earlier been declared as a
5130 lexical variable. Either qualify the sort variable with the package
5131 name, or rename the lexical variable.
5133 =item "state" variable %s can't be in a package
5135 (F) Lexically scoped variables aren't in a package, so it doesn't make
5136 sense to try to declare one with a package qualifier on the front. Use
5137 local() if you want to localize a package variable.
5139 =item stat() on unopened filehandle %s
5141 (W unopened) You tried to use the stat() function on a filehandle that
5142 was either never opened or has since been closed.
5144 =item Strings with code points over 0xFF may not be mapped into in-memory file handles
5146 (W utf8) You tried to open a reference to a scalar for read or append
5147 where the scalar contained code points over 0xFF. In-memory files
5148 model on-disk files and can only contain bytes.
5150 =item Stub found while resolving method "%s" overloading "%s" in package "%s"
5152 (P) Overloading resolution over @ISA tree may be broken by importation
5153 stubs. Stubs should never be implicitly created, but explicit calls to
5154 C<can> may break this.
5156 =item Subroutine "&%s" is not available
5158 (W closure) During compilation, an inner named subroutine or eval is
5159 attempting to capture an outer lexical subroutine that is not currently
5160 available. This can happen for one of two reasons. First, the lexical
5161 subroutine may be declared in an outer anonymous subroutine that has
5162 not yet been created. (Remember that named subs are created at compile
5163 time, while anonymous subs are created at run-time.) For example,
5165 sub { my sub a {...} sub f { \&a } }
5167 At the time that f is created, it can't capture the current "a" sub,
5168 since the anonymous subroutine hasn't been created yet. Conversely, the
5169 following won't give a warning since the anonymous subroutine has by now
5170 been created and is live:
5172 sub { my sub a {...} eval 'sub f { \&a }' }->();
5174 The second situation is caused by an eval accessing a lexical subroutine
5175 that has gone out of scope, for example,
5183 Here, when the '\&a' in the eval is being compiled, f() is not currently
5184 being executed, so its &a is not available for capture.
5186 =item "%s" subroutine &%s masks earlier declaration in same %s
5188 (W misc) A "my" or "state" subroutine has been redeclared in the
5189 current scope or statement, effectively eliminating all access to
5190 the previous instance. This is almost always a typographical error.
5191 Note that the earlier subroutine will still exist until the end of
5192 the scope or until all closure references to it are destroyed.
5194 =item Subroutine %s redefined
5196 (W redefine) You redefined a subroutine. To suppress this warning, say
5199 no warnings 'redefine';
5200 eval "sub name { ... }";
5203 =item Substitution loop
5205 (P) The substitution was looping infinitely. (Obviously, a substitution
5206 shouldn't iterate more times than there are characters of input, which
5207 is what happened.) See the discussion of substitution in
5208 L<perlop/"Regexp Quote-Like Operators">.
5210 =item Substitution pattern not terminated
5212 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
5213 construct. Remember that bracketing delimiters count nesting level.
5214 Missing the leading C<$> from variable C<$s> may cause this error.
5216 =item Substitution replacement not terminated
5218 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
5219 construct. Remember that bracketing delimiters count nesting level.
5220 Missing the leading C<$> from variable C<$s> may cause this error.
5222 =item substr outside of string
5224 (W substr)(F) You tried to reference a substr() that pointed outside of
5225 a string. That is, the absolute value of the offset was larger than the
5226 length of the string. See L<perlfunc/substr>. This warning is fatal if
5227 substr is used in an lvalue context (as the left hand side of an
5228 assignment or as a subroutine argument for example).
5230 =item sv_upgrade from type %d down to type %d
5232 (P) Perl tried to force the upgrade of an SV to a type which was actually
5233 inferior to its current type.
5235 =item SWASHNEW didn't return an HV ref
5237 (P) Something went wrong internally when Perl was trying to look up
5240 =item Switch (?(condition)... contains too many branches in regex; marked by
5241 S<<-- HERE> in m/%s/
5243 (F) A (?(condition)if-clause|else-clause) construct can have at most
5244 two branches (the if-clause and the else-clause). If you want one or
5245 both to contain alternation, such as using C<this|that|other>, enclose
5246 it in clustering parentheses:
5248 (?(condition)(?:this|that|other)|else-clause)
5250 The S<<-- HERE> shows whereabouts in the regular expression the problem
5251 was discovered. See L<perlre>.
5253 =item Switch condition not recognized in regex; marked by S<<-- HERE> in
5256 (F) The condition part of a (?(condition)if-clause|else-clause) construct
5257 is not known. The condition must be one of the following:
5259 (1) (2) ... true if 1st, 2nd, etc., capture matched
5260 (<NAME>) ('NAME') true if named capture matched
5261 (?=...) (?<=...) true if subpattern matches
5262 (?!...) (?<!...) true if subpattern fails to match
5263 (?{ CODE }) true if code returns a true value
5264 (R) true if evaluating inside recursion
5265 (R1) (R2) ... true if directly inside capture group 1, 2, etc.
5266 (R&NAME) true if directly inside named capture
5267 (DEFINE) always false; for defining named subpatterns
5269 The <-- HERE shows whereabouts in the regular expression the problem was
5270 discovered. See L<perlre>.
5272 =item switching effective %s is not implemented
5274 (F) While under the C<use filetest> pragma, we cannot switch the real
5275 and effective uids or gids.
5279 (F) Probably means you had a syntax error. Common reasons include:
5281 A keyword is misspelled.
5282 A semicolon is missing.
5284 An opening or closing parenthesis is missing.
5285 An opening or closing brace is missing.
5286 A closing quote is missing.
5288 Often there will be another error message associated with the syntax
5289 error giving more information. (Sometimes it helps to turn on B<-w>.)
5290 The error message itself often tells you where it was in the line when
5291 it decided to give up. Sometimes the actual error is several tokens
5292 before this, because Perl is good at understanding random input.
5293 Occasionally the line number may be misleading, and once in a blue moon
5294 the only way to figure out what's triggering the error is to call
5295 C<perl -c> repeatedly, chopping away half the program each time to see
5296 if the error went away. Sort of the cybernetic version of S<20 questions>.
5298 =item syntax error at line %d: '%s' unexpected
5300 (A) You've accidentally run your script through the Bourne shell instead
5301 of Perl. Check the #! line, or manually feed your script into Perl
5304 =item syntax error in file %s at line %d, next 2 tokens "%s"
5306 (F) This error is likely to occur if you run a perl5 script through
5307 a perl4 interpreter, especially if the next 2 tokens are "use strict"
5308 or "my $var" or "our $var".
5310 =item Syntax error in (?[...]) in regex m/%s/
5312 (F) Perl could not figure out what you meant inside this construct; this
5313 notifies you that it is giving up trying.
5317 (F) The final summary message when a C<perl -c> succeeds.
5319 =item sysread() on closed filehandle %s
5321 (W closed) You tried to read from a closed filehandle.
5323 =item sysread() on unopened filehandle %s
5325 (W unopened) You tried to read from a filehandle that was never opened.
5327 =item System V %s is not implemented on this machine
5329 (F) You tried to do something with a function beginning with "sem",
5330 "shm", or "msg" but that System V IPC is not implemented in your
5331 machine. In some machines the functionality can exist but be
5332 unconfigured. Consult your system support.
5334 =item syswrite() on closed filehandle %s
5336 (W closed) The filehandle you're writing to got itself closed sometime
5337 before now. Check your control flow.
5339 =item C<-T> and C<-B> not implemented on filehandles
5341 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
5342 know about your kind of stdio. You'll have to use a filename instead.
5344 =item Target of goto is too deeply nested
5346 (F) You tried to use C<goto> to reach a label that was too deeply nested
5347 for Perl to reach. Perl is doing you a favor by refusing.
5349 =item telldir() attempted on invalid dirhandle %s
5351 (W io) The dirhandle you tried to telldir() is either closed or not really
5352 a dirhandle. Check your control flow.
5354 =item tell() on unopened filehandle
5356 (W unopened) You tried to use the tell() function on a filehandle that
5357 was either never opened or has since been closed.
5359 =item That use of $[ is unsupported
5361 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
5362 as a compiler directive. You may say only one of
5371 This is to prevent the problem of one module changing the array base out
5372 from under another module inadvertently. See L<perlvar/$[> and L<arybase>.
5374 =item The crypt() function is unimplemented due to excessive paranoia.
5376 (F) Configure couldn't find the crypt() function on your machine,
5377 probably because your vendor didn't supply it, probably because they
5378 think the U.S. Government thinks it's a secret, or at least that they
5379 will continue to pretend that it is. And if you quote me on that, I
5382 =item The %s function is unimplemented
5384 (F) The function indicated isn't implemented on this architecture,
5385 according to the probings of Configure.
5387 =item The lexical_subs feature is experimental
5389 (S experimental::lexical_subs) This warning is emitted if you
5390 declare a sub with C<my> or C<state>. Simply suppress the warning
5391 if you want to use the feature, but know that in doing so you
5392 are taking the risk of using an experimental feature which may
5393 change or be removed in a future Perl version:
5395 no warnings "experimental::lexical_subs";
5396 use feature "lexical_subs";
5399 =item The regex_sets feature is experimental
5401 (S experimental::regex_sets) This warning is emitted if you
5402 use the syntax S<C<(?[ ])>> in a regular expression.
5403 The details of this feature are subject to change.
5404 if you want to use it, but know that in doing so you
5405 are taking the risk of using an experimental feature which may
5406 change in a future Perl version, you can do this to silence the
5409 no warnings "experimental::regex_sets";
5411 =item The signatures feature is experimental
5413 (S experimental::signatures) This warning is emitted if you unwrap a
5414 subroutine's arguments using a signature. Simply suppress the warning
5415 if you want to use the feature, but know that in doing so you are taking
5416 the risk of using an experimental feature which may change or be removed
5417 in a future Perl version:
5419 no warnings "experimental::signatures";
5420 use feature "signatures";
5421 sub foo ($left, $right) { ... }
5423 =item The stat preceding %s wasn't an lstat
5425 (F) It makes no sense to test the current stat buffer for symbolic
5426 linkhood if the last stat that wrote to the stat buffer already went
5427 past the symlink to get to the real file. Use an actual filename
5430 =item The 'unique' attribute may only be applied to 'our' variables
5432 (F) This attribute was never supported on C<my> or C<sub> declarations.
5434 =item This Perl can't reset CRTL environ elements (%s)
5436 =item This Perl can't set CRTL environ elements (%s=%s)
5438 (W internal) Warnings peculiar to VMS. You tried to change or delete an
5439 element of the CRTL's internal environ array, but your copy of Perl
5440 wasn't built with a CRTL that contained the setenv() function. You'll
5441 need to rebuild Perl with a CRTL that does, or redefine
5442 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
5443 target of the change to
5444 %ENV which produced the warning.
5446 =item This Perl has not been built with support for randomized hash key traversal but something called Perl_hv_rand_set().
5448 (F) Something has attempted to use an internal API call which
5449 depends on Perl being compiled with the default support for randomized hash
5450 key traversal, but this Perl has been compiled without it. You should
5451 report this warning to the relevant upstream party, or recompile perl
5452 with default options.
5454 =item times not implemented
5456 (F) Your version of the C library apparently doesn't do times(). I
5457 suspect you're not running on Unix.
5459 =item "-T" is on the #! line, it must also be used on the command line
5461 (X) The #! line (or local equivalent) in a Perl script contains
5462 the B<-T> option (or the B<-t> option), but Perl was not invoked with
5463 B<-T> in its command line. This is an error because, by the time
5464 Perl discovers a B<-T> in a script, it's too late to properly taint
5465 everything from the environment. So Perl gives up.
5467 If the Perl script is being executed as a command using the #!
5468 mechanism (or its local equivalent), this error can usually be
5469 fixed by editing the #! line so that the B<-%c> option is a part of
5470 Perl's first argument: e.g. change C<perl -n -%c> to C<perl -%c -n>.
5472 If the Perl script is being executed as C<perl scriptname>, then the
5473 B<-%c> option must appear on the command line: C<perl -%c scriptname>.
5475 =item To%s: illegal mapping '%s'
5477 (F) You tried to define a customized To-mapping for lc(), lcfirst,
5478 uc(), or ucfirst() (or their string-inlined versions), but you
5479 specified an illegal mapping.
5480 See L<perlunicode/"User-Defined Character Properties">.
5482 =item Too deeply nested ()-groups
5484 (F) Your template contains ()-groups with a ridiculously deep nesting level.
5486 =item Too few args to syscall
5488 (F) There has to be at least one argument to syscall() to specify the
5489 system call to call, silly dilly.
5491 =item Too few arguments for subroutine
5493 (F) A subroutine using a signature received fewer arguments than required
5494 by the signature. The caller of the subroutine is presumably at fault.
5495 Inconveniently, this error will be reported at the location of the
5496 subroutine, not that of the caller.
5498 =item Too late for "-%s" option
5500 (X) The #! line (or local equivalent) in a Perl script contains the
5501 B<-M>, B<-m> or B<-C> option.
5503 In the case of B<-M> and B<-m>, this is an error because those options
5504 are not intended for use inside scripts. Use the C<use> pragma instead.
5506 The B<-C> option only works if it is specified on the command line as
5507 well (with the same sequence of letters or numbers following). Either
5508 specify this option on the command line, or, if your system supports
5509 it, make your script executable and run it directly instead of passing
5512 =item Too late to run %s block
5514 (W void) A CHECK or INIT block is being defined during run time proper,
5515 when the opportunity to run them has already passed. Perhaps you are
5516 loading a file with C<require> or C<do> when you should be using C<use>
5517 instead. Or perhaps you should put the C<require> or C<do> inside a
5520 =item Too many args to syscall
5522 (F) Perl supports a maximum of only 14 args to syscall().
5524 =item Too many arguments for %s
5526 (F) The function requires fewer arguments than you specified.
5528 =item Too many arguments for subroutine
5530 (F) A subroutine using a signature received more arguments than required
5531 by the signature. The caller of the subroutine is presumably at fault.
5532 Inconveniently, this error will be reported at the location of the
5533 subroutine, not that of the caller.
5537 (A) You've accidentally run your script through B<csh> instead of Perl.
5538 Check the #! line, or manually feed your script into Perl yourself.
5542 (A) You've accidentally run your script through B<csh> instead of Perl.
5543 Check the #! line, or manually feed your script into Perl yourself.
5545 =item Trailing \ in regex m/%s/
5547 (F) The regular expression ends with an unbackslashed backslash.
5548 Backslash it. See L<perlre>.
5550 =item Trailing white-space in a charnames alias definition is deprecated
5552 (D deprecated) You defined a character name which ended in a space
5553 character. Remove the trailing space(s). Usually these names are
5554 defined in the C<:alias> import argument to C<use charnames>, but they
5555 could be defined by a translator installed into C<$^H{charnames}>.
5556 See L<charnames/CUSTOM ALIASES>.
5558 =item Transliteration pattern not terminated
5560 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
5561 or y/// or y[][] construct. Missing the leading C<$> from variables
5562 C<$tr> or C<$y> may cause this error.
5564 =item Transliteration replacement not terminated
5566 (F) The lexer couldn't find the final delimiter of a tr///, tr[][],
5567 y/// or y[][] construct.
5569 =item '%s' trapped by operation mask
5571 (F) You tried to use an operator from a Safe compartment in which it's
5572 disallowed. See L<Safe>.
5574 =item truncate not implemented
5576 (F) Your machine doesn't implement a file truncation mechanism that
5577 Configure knows about.
5579 =item Type of arg %d to &CORE::%s must be %s
5581 (F) The subroutine in question in the CORE package requires its argument
5582 to be a hard reference to data of the specified type. Overloading is
5583 ignored, so a reference to an object that is not the specified type, but
5584 nonetheless has overloading to handle it, will still not be accepted.
5586 =item Type of arg %d to %s must be %s (not %s)
5588 (F) This function requires the argument in that position to be of a
5589 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
5590 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
5591 {EXPR} forms as an explicit dereference. See L<perlref>.
5593 =item Type of argument to %s must be unblessed hashref or arrayref
5595 (F) You called C<keys>, C<values> or C<each> with a scalar argument that
5596 was not a reference to an unblessed hash or array.
5598 =item umask not implemented
5600 (F) Your machine doesn't implement the umask function and you tried to
5601 use it to restrict permissions for yourself (EXPR & 0700).
5603 =item Unbalanced context: %d more PUSHes than POPs
5605 (S internal) The exit code detected an internal inconsistency in how
5606 many execution contexts were entered and left.
5608 =item Unbalanced saves: %d more saves than restores
5610 (S internal) The exit code detected an internal inconsistency in how
5611 many values were temporarily localized.
5613 =item Unbalanced scopes: %d more ENTERs than LEAVEs
5615 (S internal) The exit code detected an internal inconsistency in how
5616 many blocks were entered and left.
5618 =item Unbalanced string table refcount: (%d) for "%s"
5620 (S internal) On exit, Perl found some strings remaining in the shared
5621 string table used for copy on write and for hash keys. The entries
5622 should have been freed, so this indicates a bug somewhere.
5624 =item Unbalanced tmps: %d more allocs than frees
5626 (S internal) The exit code detected an internal inconsistency in how
5627 many mortal scalars were allocated and freed.
5629 =item Undefined format "%s" called
5631 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5632 another package? See L<perlform>.
5634 =item Undefined sort subroutine "%s" called
5636 (F) The sort comparison routine specified doesn't seem to exist.
5637 Perhaps it's in a different package? See L<perlfunc/sort>.
5639 =item Undefined subroutine &%s called
5641 (F) The subroutine indicated hasn't been defined, or if it was, it has
5642 since been undefined.
5644 =item Undefined subroutine called
5646 (F) The anonymous subroutine you're trying to call hasn't been defined,
5647 or if it was, it has since been undefined.
5649 =item Undefined subroutine in sort
5651 (F) The sort comparison routine specified is declared but doesn't seem
5652 to have been defined yet. See L<perlfunc/sort>.
5654 =item Undefined top format "%s" called
5656 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5657 another package? See L<perlform>.
5659 =item Undefined value assigned to typeglob
5661 (W misc) An undefined value was assigned to a typeglob, a la
5662 C<*foo = undef>. This does nothing. It's possible that you really mean
5665 =item %s: Undefined variable
5667 (A) You've accidentally run your script through B<csh> instead of Perl.
5668 Check the #! line, or manually feed your script into Perl yourself.
5670 =item unexec of %s into %s failed!
5672 (F) The unexec() routine failed for some reason. See your local FSF
5673 representative, who probably put it there in the first place.
5675 =item Unexpected binary operator '%c' with no preceding operand in regex;
5676 marked by S<<-- HERE> in m/%s/
5678 (F) You had something like this:
5682 where the C<"|"> is a binary operator with an operand on the right, but
5683 no operand on the left.
5685 =item Unexpected character in regex; marked by S<<-- HERE> in m/%s/
5687 (F) You had something like this:
5691 Within C<(?[ ])>, no literal characters are allowed unless they are
5692 within an inner pair of square brackets, like
5696 Another possibility is that you forgot a backslash. Perl isn't smart
5697 enough to figure out what you really meant.
5699 =item Unexpected constant lvalue entersub entry via type/targ %d:%d
5701 (P) When compiling a subroutine call in lvalue context, Perl failed an
5702 internal consistency check. It encountered a malformed op tree.
5704 =item Unexpected exit %u
5706 (S) exit() was called or the script otherwise finished gracefully when
5707 C<PERL_EXIT_WARN> was set in C<PL_exit_flags>.
5709 =item Unexpected exit failure %d
5711 (S) An uncaught die() was called when C<PERL_EXIT_WARN> was set in
5714 =item Unexpected ')' in regex; marked by S<<-- HERE> in m/%s/
5716 (F) You had something like this:
5718 (?[ ( \p{Digit} + ) ])
5720 The C<")"> is out-of-place. Something apparently was supposed to
5721 be combined with the digits, or the C<"+"> shouldn't be there, or
5722 something like that. Perl can't figure out what was intended.
5724 =item Unexpected '(' with no preceding operator in regex; marked by
5725 S<<-- HERE> in m/%s/
5727 (F) You had something like this:
5729 (?[ \p{Digit} ( \p{Lao} + \p{Thai} ) ])
5731 There should be an operator before the C<"(">, as there's
5732 no indication as to how the digits are to be combined
5733 with the characters in the Lao and Thai scripts.
5735 =item Unicode non-character U+%X is illegal for open interchange
5737 (S nonchar) Certain codepoints, such as U+FFFE and U+FFFF, are
5738 defined by the Unicode standard to be non-characters. Those are
5739 legal codepoints, but are reserved for internal use; so, applications
5740 shouldn't attempt to exchange them. If you know what you are doing
5741 you can turn off this warning by C<no warnings 'nonchar';>.
5743 =item Unicode surrogate U+%X is illegal in UTF-8
5745 (S surrogate) You had a UTF-16 surrogate in a context where they are
5746 not considered acceptable. These code points, between U+D800 and
5747 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
5748 internally allows all unsigned integer code points (up to the size limit
5749 available on your platform), including surrogates. But these can cause
5750 problems when being input or output, which is likely where this message
5751 came from. If you really really know what you are doing you can turn
5752 off this warning by C<no warnings 'surrogate';>.
5754 =item Unknown charname '%s'
5756 (F) The name you used inside C<\N{}> is unknown to Perl. Check the
5757 spelling. You can say C<use charnames ":loose"> to not have to be
5758 so precise about spaces, hyphens, and capitalization on standard Unicode
5759 names. (Any custom aliases that have been created must be specified
5760 exactly, regardless of whether C<:loose> is used or not.) This error may
5761 also happen if the C<\N{}> is not in the scope of the corresponding
5762 C<S<use charnames>>.
5766 (P) Perl was about to print an error message in C<$@>, but the C<$@> variable
5767 did not exist, even after an attempt to create it.
5769 =item Unknown open() mode '%s'
5771 (F) The second argument of 3-argument open() is not among the list
5772 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
5773 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
5775 =item Unknown PerlIO layer "%s"
5777 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
5778 system. (Layers take care of transforming data between external and
5779 internal representations.) Note that some layers, such as C<mmap>,
5780 are not supported in all environments. If your program didn't
5781 explicitly request the failing operation, it may be the result of the
5782 value of the environment variable PERLIO.
5784 =item Unknown process %x sent message to prime_env_iter: %s
5786 (P) An error peculiar to VMS. Perl was reading values for %ENV before
5787 iterating over it, and someone else stuck a message in the stream of
5788 data Perl expected. Someone's very confused, or perhaps trying to
5789 subvert Perl's population of %ENV for nefarious purposes.
5791 =item Unknown regex modifier "%s"
5793 (F) Alphanumerics immediately following the closing delimiter
5794 of a regular expression pattern are interpreted by Perl as modifier
5795 flags for the regex. One of the ones you specified is invalid. One way
5796 this can happen is if you didn't put in white space between the end of
5797 the regex and a following alphanumeric operator:
5799 if ($a =~ /foo/and $bar == 3) { ... }
5801 The C<"a"> is a valid modifier flag, but the C<"n"> is not, and raises
5802 this error. Likely what was meant instead was:
5804 if ($a =~ /foo/ and $bar == 3) { ... }
5806 =item Unknown "re" subpragma '%s' (known ones are: %s)
5808 (W) You tried to use an unknown subpragma of the "re" pragma.
5810 =item Unknown switch condition (?(...)) in regex; marked by S<<-- HERE> in
5813 (F) The condition part of a (?(condition)if-clause|else-clause) construct
5814 is not known. The condition must be one of the following:
5816 (1) (2) ... true if 1st, 2nd, etc., capture matched
5817 (<NAME>) ('NAME') true if named capture matched
5818 (?=...) (?<=...) true if subpattern matches
5819 (?!...) (?<!...) true if subpattern fails to match
5820 (?{ CODE }) true if code returns a true value
5821 (R) true if evaluating inside recursion
5822 (R1) (R2) ... true if directly inside capture group 1, 2, etc.
5823 (R&NAME) true if directly inside named capture
5824 (DEFINE) always false; for defining named subpatterns
5826 The <-- HERE shows whereabouts in the regular expression the problem was
5827 discovered. See L<perlre>.
5829 =item Unknown Unicode option letter '%c'
5831 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5832 of the C<-C> switch for the list of known options.
5834 =item Unknown Unicode option value %d
5836 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5837 of the C<-C> switch for the list of known options.
5839 =item Unknown verb pattern '%s' in regex; marked by S<<-- HERE> in m/%s/
5841 (F) You either made a typo or have incorrectly put a C<*> quantifier
5842 after an open brace in your pattern. Check the pattern and review
5843 L<perlre> for details on legal verb patterns.
5845 =item Unknown warnings category '%s'
5847 (F) An error issued by the C<warnings> pragma. You specified a warnings
5848 category that is unknown to perl at this point.
5850 Note that if you want to enable a warnings category registered by a
5851 module (e.g. C<use warnings 'File::Find'>), you must have loaded this
5854 =item Unmatched '[' in POSIX class in regex; marked by S<<-- HERE> in m/%s/
5856 (F) You had something like this:
5860 That should be written:
5864 =item Unmatched '%c' in POSIX class in regex; marked by S<<-- HERE> in
5867 (F) You had something like this:
5871 There should be a second C<":">, like this:
5875 =item Unmatched [ in regex; marked by S<<-- HERE> in m/%s/
5877 (F) The brackets around a character class must match. If you wish to
5878 include a closing bracket in a character class, backslash it or put it
5879 first. The S<<-- HERE> shows whereabouts in the regular expression the
5880 problem was discovered. See L<perlre>.
5882 =item Unmatched ( in regex; marked by S<<-- HERE> in m/%s/
5884 =item Unmatched ) in regex; marked by S<<-- HERE> in m/%s/
5886 (F) Unbackslashed parentheses must always be balanced in regular
5887 expressions. If you're a vi user, the % key is valuable for finding
5888 the matching parenthesis. The S<<-- HERE> shows whereabouts in the
5889 regular expression the problem was discovered. See L<perlre>.
5891 =item Unmatched right %s bracket
5893 (F) The lexer counted more closing curly or square brackets than opening
5894 ones, so you're probably missing a matching opening bracket. As a
5895 general rule, you'll find the missing one (so to speak) near the place
5896 you were last editing.
5898 =item Unquoted string "%s" may clash with future reserved word
5900 (W reserved) You used a bareword that might someday be claimed as a
5901 reserved word. It's best to put such a word in quotes, or capitalize it
5902 somehow, or insert an underbar into it. You might also declare it as a
5905 =item Unrecognized character %s; marked by S<<-- HERE> after %s near column
5908 (F) The Perl parser has no idea what to do with the specified character
5909 in your Perl script (or eval) near the specified column. Perhaps you
5910 tried to run a compressed script, a binary program, or a directory as
5913 =item Unrecognized escape \%c in character class in regex; marked by
5914 S<<-- HERE> in m/%s/
5916 (F) You used a backslash-character combination which is not
5917 recognized by Perl inside character classes. This is a fatal
5918 error when the character class is used within C<(?[ ])>.
5920 =item Unrecognized escape \%c in character class passed through in regex;
5921 marked by S<<-- HERE> in m/%s/
5923 (W regexp) You used a backslash-character combination which is not
5924 recognized by Perl inside character classes. The character was
5925 understood literally, but this may change in a future version of Perl.
5926 The S<<-- HERE> shows whereabouts in the regular expression the
5927 escape was discovered.
5929 =item Unrecognized escape \%c passed through
5931 (W misc) You used a backslash-character combination which is not
5932 recognized by Perl. The character was understood literally, but this may
5933 change in a future version of Perl.
5935 =item Unrecognized escape \%s passed through in regex; marked by
5936 S<<-- HERE> in m/%s/
5938 (W regexp) You used a backslash-character combination which is not
5939 recognized by Perl. The character(s) were understood literally, but
5940 this may change in a future version of Perl. The S<<-- HERE> shows
5941 whereabouts in the regular expression the escape was discovered.
5943 =item Unrecognized signal name "%s"
5945 (F) You specified a signal name to the kill() function that was not
5946 recognized. Say C<kill -l> in your shell to see the valid signal names
5949 =item Unrecognized switch: -%s (-h will show valid options)
5951 (F) You specified an illegal option to Perl. Don't do that. (If you
5952 think you didn't do that, check the #! line to see if it's supplying the
5953 bad switch on your behalf.)
5955 =item unshift on reference is experimental
5957 (S experimental::autoderef) C<unshift> with a scalar argument
5958 is experimental and may change or be removed in a future
5959 Perl version. If you want to take the risk of using this
5960 feature, simply disable this warning:
5962 no warnings "experimental::autoderef";
5964 =item Unsuccessful %s on filename containing newline
5966 (W newline) A file operation was attempted on a filename, and that
5967 operation failed, PROBABLY because the filename contained a newline,
5968 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
5970 =item Unsupported directory function "%s" called
5972 (F) Your machine doesn't support opendir() and readdir().
5974 =item Unsupported function %s
5976 (F) This machine doesn't implement the indicated function, apparently.
5977 At least, Configure doesn't think so.
5979 =item Unsupported function fork
5981 (F) Your version of executable does not support forking.
5983 Note that under some systems, like OS/2, there may be different flavors
5984 of Perl executables, some of which may support fork, some not. Try
5985 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
5987 =item Unsupported script encoding %s
5989 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
5990 declares it to be in a Unicode encoding that Perl cannot read.
5992 =item Unsupported socket function "%s" called
5994 (F) Your machine doesn't support the Berkeley socket mechanism, or at
5995 least that's what Configure thought.
5997 =item Unterminated attribute list
5999 (F) The lexer found something other than a simple identifier at the
6000 start of an attribute, and it wasn't a semicolon or the start of a
6001 block. Perhaps you terminated the parameter list of the previous
6002 attribute too soon. See L<attributes>.
6004 =item Unterminated attribute parameter in attribute list
6006 (F) The lexer saw an opening (left) parenthesis character while parsing
6007 an attribute list, but the matching closing (right) parenthesis
6008 character was not found. You may need to add (or remove) a backslash
6009 character to get your parentheses to balance. See L<attributes>.
6011 =item Unterminated compressed integer
6013 (F) An argument to unpack("w",...) was incompatible with the BER
6014 compressed integer format and could not be converted to an integer.
6015 See L<perlfunc/pack>.
6017 =item Unterminated delimiter for here document
6019 (F) This message occurs when a here document label has an initial
6020 quotation mark but the final quotation mark is missing. Perhaps
6029 =item Unterminated \g... pattern in regex; marked by S<<-- HERE> in m/%s/
6031 =item Unterminated \g{...} pattern in regex; marked by S<<-- HERE> in m/%s/
6033 (F) In a regular expression, you had a C<\g> that wasn't followed by a
6034 proper group reference. In the case of C<\g{>, the closing brace is
6035 missing; otherwise the C<\g> must be followed by an integer. Fix the
6038 =item Unterminated <> operator
6040 (F) The lexer saw a left angle bracket in a place where it was expecting
6041 a term, so it's looking for the corresponding right angle bracket, and
6042 not finding it. Chances are you left some needed parentheses out
6043 earlier in the line, and you really meant a "less than".
6045 =item Unterminated verb pattern argument in regex; marked by S<<-- HERE> in
6048 (F) You used a pattern of the form C<(*VERB:ARG)> but did not terminate
6049 the pattern with a C<)>. Fix the pattern and retry.
6051 =item Unterminated verb pattern in regex; marked by S<<-- HERE> in m/%s/
6053 (F) You used a pattern of the form C<(*VERB)> but did not terminate
6054 the pattern with a C<)>. Fix the pattern and retry.
6056 =item untie attempted while %d inner references still exist
6058 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
6059 still valid when C<untie> was called.
6061 =item Usage: POSIX::%s(%s)
6063 (F) You called a POSIX function with incorrect arguments.
6064 See L<POSIX/FUNCTIONS> for more information.
6066 =item Usage: Win32::%s(%s)
6068 (F) You called a Win32 function with incorrect arguments.
6069 See L<Win32> for more information.
6071 =item $[ used in %s (did you mean $] ?)
6073 (W syntax) You used C<$[> in a comparison, such as:
6079 You probably meant to use C<$]> instead. C<$[> is the base for indexing
6080 arrays. C<$]> is the Perl version number in decimal.
6082 =item Use "%s" instead of "%s"
6084 (F) The second listed construct is no longer legal. Use the first one
6087 =item Useless assignment to a temporary
6089 (W misc) You assigned to an lvalue subroutine, but what
6090 the subroutine returned was a temporary scalar about to
6091 be discarded, so the assignment had no effect.
6093 =item Useless (?-%s) - don't use /%s modifier in regex; marked by
6094 S<<-- HERE> in m/%s/
6096 (W regexp) You have used an internal modifier such as (?-o) that has no
6097 meaning unless removed from the entire regexp:
6099 if ($string =~ /(?-o)$pattern/o) { ... }
6103 if ($string =~ /$pattern/) { ... }
6105 The <-- HERE shows whereabouts in the regular expression the problem was
6106 discovered. See L<perlre>.
6108 =item Useless localization of %s
6110 (W syntax) The localization of lvalues such as C<local($x=10)> is legal,
6111 but in fact the local() currently has no effect. This may change at
6112 some point in the future, but in the meantime such code is discouraged.
6114 =item Useless (?%s) - use /%s modifier in regex; marked by S<<-- HERE> in
6117 (W regexp) You have used an internal modifier such as (?o) that has no
6118 meaning unless applied to the entire regexp:
6120 if ($string =~ /(?o)$pattern/) { ... }
6124 if ($string =~ /$pattern/o) { ... }
6126 The <-- HERE shows whereabouts in the regular expression the problem was
6127 discovered. See L<perlre>.
6129 =item Useless use of /d modifier in transliteration operator
6131 (W misc) You have used the /d modifier where the searchlist has the
6132 same length as the replacelist. See L<perlop> for more information
6133 about the /d modifier.
6135 =item Useless use of '\'; doesn't escape metacharacter '%c'
6137 (D deprecated) You wrote a regular expression pattern something like
6143 s[foo\[a-z\]bar][baz]
6145 The interior braces, square brackets, and parentheses are treated as
6146 metacharacters even though they are backslashed; instead write:
6153 The backslashes have no effect when a regular expression pattern is
6154 delimited by C<{}>, C<[]>, or C<()>, which ordinarily are
6155 metacharacters, and the delimiters are also used, paired, within the
6156 interior of the pattern. It is planned that a future Perl release will
6157 change the meaning of constructs like these so that the backslashes
6158 will have an effect, so remove them from your code.
6160 =item Useless use of \E
6162 (W misc) You have a \E in a double-quotish string without a C<\U>,
6163 C<\L> or C<\Q> preceding it.
6165 =item Useless use of greediness modifier '%c' in regex; marked by S<<-- HERE> in m/%s/
6167 (W regexp) You specified something like these:
6172 The C<"?"> and C<"+"> don't have any effect, as they modify whether to
6173 match more or fewer when there is a choice, and by specifying to match
6174 exactly a given numer, there is no room left for a choice.
6176 =item Useless use of %s in void context
6178 (W void) You did something without a side effect in a context that does
6179 nothing with the return value, such as a statement that doesn't return a
6180 value from a block, or the left side of a scalar comma operator. Very
6181 often this points not to stupidity on your part, but a failure of Perl
6182 to parse your program the way you thought it would. For example, you'd
6183 get this if you mixed up your C precedence with Python precedence and
6188 when you meant to say
6190 ($one, $two) = (1, 2);
6192 Another common error is to use ordinary parentheses to construct a list
6193 reference when you should be using square or curly brackets, for
6198 when you should have said
6202 The square brackets explicitly turn a list value into a scalar value,
6203 while parentheses do not. So when a parenthesized list is evaluated in
6204 a scalar context, the comma is treated like C's comma operator, which
6205 throws away the left argument, which is not what you want. See
6206 L<perlref> for more on this.
6208 This warning will not be issued for numerical constants equal to 0 or 1
6209 since they are often used in statements like
6211 1 while sub_with_side_effects();
6213 String constants that would normally evaluate to 0 or 1 are warned
6216 =item Useless use of (?-p) in regex; marked by S<<-- HERE> in m/%s/
6218 (W regexp) The C<p> modifier cannot be turned off once set. Trying to do
6221 =item Useless use of "re" pragma
6223 (W) You did C<use re;> without any arguments. That isn't very useful.
6225 =item Useless use of sort in scalar context
6227 (W void) You used sort in scalar context, as in :
6231 This is not very useful, and perl currently optimizes this away.
6233 =item Useless use of %s with no values
6235 (W syntax) You used the push() or unshift() function with no arguments
6236 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
6237 usually have any effect on the array, so is completely useless. It's
6238 possible in principle that push(@tied_array) could have some effect
6239 if the array is tied to a class which implements a PUSH method. If so,
6240 you can write it as C<push(@tied_array,())> to avoid this warning.
6242 =item "use" not allowed in expression
6244 (F) The "use" keyword is recognized and executed at compile time, and
6245 returns no useful value. See L<perlmod>.
6247 =item Use of assignment to $[ is deprecated
6249 (D deprecated) The C<$[> variable (index of the first element in an array)
6250 is deprecated. See L<perlvar/"$[">.
6252 =item Use of bare << to mean <<"" is deprecated
6254 (D deprecated) You are now encouraged to use the explicitly quoted
6255 form if you wish to use an empty line as the terminator of the
6258 =item Use of chdir('') or chdir(undef) as chdir() deprecated
6260 (D deprecated) chdir() with no arguments is documented to change to
6261 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
6262 behavior, but that has been deprecated. In future versions they
6265 Be careful to check that what you pass to chdir() is defined and not
6266 blank, else you might find yourself in your home directory.
6268 =item Use of /c modifier is meaningless in s///
6270 (W regexp) You used the /c modifier in a substitution. The /c
6271 modifier is not presently meaningful in substitutions.
6273 =item Use of /c modifier is meaningless without /g
6275 (W regexp) You used the /c modifier with a regex operand, but didn't
6276 use the /g modifier. Currently, /c is meaningful only when /g is
6277 used. (This may change in the future.)
6279 =item Use of comma-less variable list is deprecated
6281 (D deprecated) The values you give to a format should be
6282 separated by commas, not just aligned on a line.
6284 =item Use of each() on hash after insertion without resetting hash iterator results in undefined behavior
6286 (S internal) The behavior of C<each()> after insertion is undefined;
6287 it may skip items, or visit items more than once. Consider using
6288 C<keys()> instead of C<each()>.
6290 =item Use of := for an empty attribute list is not allowed
6292 (F) The construction C<my $x := 42> used to parse as equivalent to
6293 C<my $x : = 42> (applying an empty attribute list to C<$x>).
6294 This construct was deprecated in 5.12.0, and has now been made a syntax
6295 error, so C<:=> can be reclaimed as a new operator in the future.
6297 If you need an empty attribute list, for example in a code generator, add
6298 a space before the C<=>.
6300 =item Use of freed value in iteration
6302 (F) Perhaps you modified the iterated array within the loop?
6303 This error is typically caused by code like the following:
6306 @a = () for (1,2,@a);
6308 You are not supposed to modify arrays while they are being iterated over.
6309 For speed and efficiency reasons, Perl internally does not do full
6310 reference-counting of iterated items, hence deleting such an item in the
6311 middle of an iteration causes Perl to see a freed value.
6313 =item Use of *glob{FILEHANDLE} is deprecated
6315 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
6316 to access the filehandle slot within a typeglob.
6318 =item Use of /g modifier is meaningless in split
6320 (W regexp) You used the /g modifier on the pattern for a C<split>
6321 operator. Since C<split> always tries to match the pattern
6322 repeatedly, the C</g> has no effect.
6324 =item Use of "goto" to jump into a construct is deprecated
6326 (D deprecated) Using C<goto> to jump from an outer scope into an inner
6327 scope is deprecated and should be avoided.
6329 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
6331 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD>
6332 subroutines are looked up as methods (using the C<@ISA> hierarchy)
6333 even when the subroutines to be autoloaded were called as plain
6334 functions (e.g. C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or
6335 C<< $obj->bar() >>).
6337 This bug will be rectified in future by using method lookup only for
6338 methods' C<AUTOLOAD>s. However, there is a significant base of existing
6339 code that may be using the old behavior. So, as an interim step, Perl
6340 currently issues an optional warning when non-methods use inherited
6343 The simple rule is: Inheritance will not work when autoloading
6344 non-methods. The simple fix for old code is: In any module that used
6345 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
6346 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
6349 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
6350 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
6351 C<use AutoLoader 'AUTOLOAD';>.
6353 =item Use of %s in printf format not supported
6355 (F) You attempted to use a feature of printf that is accessible from
6356 only C. This usually means there's a better way to do it in Perl.
6358 =item Use of %s is deprecated
6360 (D deprecated) The construct indicated is no longer recommended for use,
6361 generally because there's a better way to do it, and also because the
6362 old way has bad side effects.
6364 =item Use of literal control characters in variable names is deprecated
6366 (D deprecated) Using literal control characters in the source to refer
6367 to the ^FOO variables, like C<$^X> and C<${^GLOBAL_PHASE}> is now
6368 deprecated. This only affects code like C<$\cT>, where \cT is a control in
6369 the source code: C<${"\cT"}> and C<$^T> remain valid.
6371 =item Use of -l on filehandle%s
6373 (W io) A filehandle represents an opened file, and when you opened the file
6374 it already went past any symlink you are presumably trying to look for.
6375 The operation returned C<undef>. Use a filename instead.
6377 =item Use of my $_ is experimental
6379 (S experimental::lexical_topic) Lexical $_ is an experimental feature and
6380 its behavior may change or even be removed in any future release of perl.
6381 See the explanation under L<perlvar/$_>.
6383 =item Use of %s on a handle without * is deprecated
6385 (D deprecated) You used C<tie>, C<tied> or C<untie> on a scalar but that scalar
6386 happens to hold a typeglob, which means its filehandle will be tied. If
6387 you mean to tie a handle, use an explicit * as in C<tie *$handle>.
6389 This was a long-standing bug that was removed in Perl 5.16, as there was
6390 no way to tie the scalar itself when it held a typeglob, and no way to
6391 untie a scalar that had had a typeglob assigned to it. If you see this
6392 message, you must be using an older version.
6394 =item Use of ?PATTERN? without explicit operator is deprecated
6396 (D deprecated) You have written something like C<?\w?>, for a regular
6397 expression that matches only once. Starting this term directly with
6398 the question mark delimiter is now deprecated, so that the question mark
6399 will be available for use in new operators in the future. Write C<m?\w?>
6400 instead, explicitly using the C<m> operator: the question mark delimiter
6401 still invokes match-once behaviour.
6403 =item Use of reference "%s" as array index
6405 (W misc) You tried to use a reference as an array index; this probably
6406 isn't what you mean, because references in numerical context tend
6407 to be huge numbers, and so usually indicates programmer error.
6409 If you really do mean it, explicitly numify your reference, like so:
6410 C<$array[0+$ref]>. This warning is not given for overloaded objects,
6411 however, because you can overload the numification and stringification
6412 operators and then you presumably know what you are doing.
6414 =item Use of state $_ is experimental
6416 (S experimental::lexical_topic) Lexical $_ is an experimental feature and
6417 its behavior may change or even be removed in any future release of perl.
6418 See the explanation under L<perlvar/$_>.
6420 =item Use of tainted arguments in %s is deprecated
6422 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
6423 arguments and at least one of them is tainted. This used to be allowed
6424 but will become a fatal error in a future version of perl. Untaint your
6425 arguments. See L<perlsec>.
6427 =item Use of uninitialized value%s
6429 (W uninitialized) An undefined value was used as if it were already
6430 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
6431 To suppress this warning assign a defined value to your variables.
6433 To help you figure out what was undefined, perl will try to tell you
6434 the name of the variable (if any) that was undefined. In some cases
6435 it cannot do this, so it also tells you what operation you used the
6436 undefined value in. Note, however, that perl optimizes your program
6437 and the operation displayed in the warning may not necessarily appear
6438 literally in your program. For example, C<"that $foo"> is usually
6439 optimized into C<"that " . $foo>, and the warning will refer to the
6440 C<concatenation (.)> operator, even though there is no C<.> in
6443 =item Use \x{...} for more than two hex characters in regex; marked by
6444 S<<-- HERE> in m/%s/
6446 (F) In a regular expression, you said something like
6450 Perl isn't sure if you meant this
6454 or if you meant this
6456 (?[ [ \x{BE} E F ] ])
6458 You need to add either braces or blanks to disambiguate.
6460 =item Using a hash as a reference is deprecated
6462 (D deprecated) You tried to use a hash as a reference, as in
6463 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
6464 used to allow this syntax, but shouldn't have. It is now
6465 deprecated, and will be removed in a future version.
6467 =item Using an array as a reference is deprecated
6469 (D deprecated) You tried to use an array as a reference, as in
6470 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
6471 allow this syntax, but shouldn't have. It is now deprecated,
6472 and will be removed in a future version.
6474 =item Using just the first character returned by \N{} in character class in
6475 regex; marked by S<<-- HERE> in m/%s/
6477 (W regexp) A charnames handler may return a sequence of more than one
6478 character. Currently all but the first one are discarded when used in
6479 a regular expression pattern bracketed character class.
6481 =item Using !~ with %s doesn't make sense
6483 (F) Using the C<!~> operator with C<s///r>, C<tr///r> or C<y///r> is
6484 currently reserved for future use, as the exact behaviour has not
6485 been decided. (Simply returning the boolean opposite of the
6486 modified string is usually not particularly useful.)
6488 =item UTF-16 surrogate U+%X
6490 (S surrogate) You had a UTF-16 surrogate in a context where they are
6491 not considered acceptable. These code points, between U+D800 and
6492 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
6493 internally allows all unsigned integer code points (up to the size limit
6494 available on your platform), including surrogates. But these can cause
6495 problems when being input or output, which is likely where this message
6496 came from. If you really really know what you are doing you can turn
6497 off this warning by C<no warnings 'surrogate';>.
6499 =item Value of %s can be "0"; test with defined()
6501 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
6502 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
6503 can return a value of "0"; that would make the conditional expression
6504 false, which is probably not what you intended. When using these
6505 constructs in conditional expressions, test their values with the
6506 C<defined> operator.
6508 =item Value of CLI symbol "%s" too long
6510 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
6511 %ENV element from a CLI symbol table, and found a resultant string
6512 longer than 1024 characters. The return value has been truncated to
6515 =item values on reference is experimental
6517 (S experimental::autoderef) C<values> with a scalar argument
6518 is experimental and may change or be removed in a future
6519 Perl version. If you want to take the risk of using this
6520 feature, simply disable this warning:
6522 no warnings "experimental::autoderef";
6524 =item Variable "%s" is not available
6526 (W closure) During compilation, an inner named subroutine or eval is
6527 attempting to capture an outer lexical that is not currently available.
6528 This can happen for one of two reasons. First, the outer lexical may be
6529 declared in an outer anonymous subroutine that has not yet been created.
6530 (Remember that named subs are created at compile time, while anonymous
6531 subs are created at run-time.) For example,
6533 sub { my $a; sub f { $a } }
6535 At the time that f is created, it can't capture the current value of $a,
6536 since the anonymous subroutine hasn't been created yet. Conversely,
6537 the following won't give a warning since the anonymous subroutine has by
6538 now been created and is live:
6540 sub { my $a; eval 'sub f { $a }' }->();
6542 The second situation is caused by an eval accessing a variable that has
6543 gone out of scope, for example,
6551 Here, when the '$a' in the eval is being compiled, f() is not currently
6552 being executed, so its $a is not available for capture.
6554 =item Variable "%s" is not imported%s
6556 (S misc) With "use strict" in effect, you referred to a global variable
6557 that you apparently thought was imported from another module, because
6558 something else of the same name (usually a subroutine) is exported by
6559 that module. It usually means you put the wrong funny character on the
6560 front of your variable.
6562 =item Variable length lookbehind not implemented in regex m/%s/
6564 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
6565 known at compile time. See L<perlre>.
6567 =item "%s" variable %s masks earlier declaration in same %s
6569 (W misc) A "my", "our" or "state" variable has been redeclared in the
6570 current scope or statement, effectively eliminating all access to the
6571 previous instance. This is almost always a typographical error. Note
6572 that the earlier variable will still exist until the end of the scope
6573 or until all closure references to it are destroyed.
6575 =item Variable syntax
6577 (A) You've accidentally run your script through B<csh> instead
6578 of Perl. Check the #! line, or manually feed your script into
6581 =item Variable "%s" will not stay shared
6583 (W closure) An inner (nested) I<named> subroutine is referencing a
6584 lexical variable defined in an outer named subroutine.
6586 When the inner subroutine is called, it will see the value of
6587 the outer subroutine's variable as it was before and during the *first*
6588 call to the outer subroutine; in this case, after the first call to the
6589 outer subroutine is complete, the inner and outer subroutines will no
6590 longer share a common value for the variable. In other words, the
6591 variable will no longer be shared.
6593 This problem can usually be solved by making the inner subroutine
6594 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
6595 reference variables in outer subroutines are created, they
6596 are automatically rebound to the current values of such variables.
6598 =item vector argument not supported with alpha versions
6600 (S printf) The %vd (s)printf format does not support version objects
6603 =item Verb pattern '%s' has a mandatory argument in regex; marked by
6604 S<<-- HERE> in m/%s/
6606 (F) You used a verb pattern that requires an argument. Supply an
6607 argument or check that you are using the right verb.
6609 =item Verb pattern '%s' may not have an argument in regex; marked by
6610 S<<-- HERE> in m/%s/
6612 (F) You used a verb pattern that is not allowed an argument. Remove the
6613 argument or check that you are using the right verb.
6615 =item Version number must be a constant number
6617 (P) The attempt to translate a C<use Module n.n LIST> statement into
6618 its equivalent C<BEGIN> block found an internal inconsistency with
6621 =item Version string '%s' contains invalid data; ignoring: '%s'
6623 (W misc) The version string contains invalid characters at the end, which
6626 =item Warning: something's wrong
6628 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
6629 you called it with no args and C<$@> was empty.
6631 =item Warning: unable to close filehandle %s properly
6633 (S) The implicit close() done by an open() got an error indication on
6634 the close(). This usually indicates your file system ran out of disk
6637 =item Warning: Use of "%s" without parentheses is ambiguous
6639 (S ambiguous) You wrote a unary operator followed by something that
6640 looks like a binary operator that could also have been interpreted as a
6641 term or unary operator. For instance, if you know that the rand
6642 function has a default argument of 1.0, and you write
6646 you may THINK you wrote the same thing as
6650 but in actual fact, you got
6654 So put in parentheses to say what you really mean.
6656 =item when is experimental
6658 (S experimental::smartmatch) C<when> depends on smartmatch, which is
6659 experimental. Additionally, it has several special cases that may
6660 not be immediately obvious, and their behavior may change or
6661 even be removed in any future release of perl. See the explanation
6662 under L<perlsyn/Experimental Details on given and when>.
6664 =item Wide character in %s
6666 (S utf8) Perl met a wide character (>255) when it wasn't expecting
6667 one. This warning is by default on for I/O (like print). The easiest
6668 way to quiet this warning is simply to add the C<:utf8> layer to the
6669 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
6670 warning is to add C<no warnings 'utf8';> but that is often closer to
6671 cheating. In general, you are supposed to explicitly mark the
6672 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
6674 =item Within []-length '%c' not allowed
6676 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]>
6677 only if C<TEMPLATE> always matches the same amount of packed bytes that
6678 can be determined from the template alone. This is not possible if
6679 it contains any of the codes @, /, U, u, w or a *-length. Redesign
6682 =item write() on closed filehandle %s
6684 (W closed) The filehandle you're writing to got itself closed sometime
6685 before now. Check your control flow.
6687 =item %s "\x%X" does not map to Unicode
6689 (S utf8) When reading in different encodings, Perl tries to
6690 map everything into Unicode characters. The bytes you read
6691 in are not legal in this encoding. For example
6693 utf8 "\xE4" does not map to Unicode
6695 if you try to read in the a-diaereses Latin-1 as UTF-8.
6697 =item 'X' outside of string
6699 (F) You had a (un)pack template that specified a relative position before
6700 the beginning of the string being (un)packed. See L<perlfunc/pack>.
6702 =item 'x' outside of string in unpack
6704 (F) You had a pack template that specified a relative position after
6705 the end of the string being unpacked. See L<perlfunc/pack>.
6707 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
6709 (F) And you probably never will, because you probably don't have the
6710 sources to your kernel, and your vendor probably doesn't give a rip
6711 about what you want. Your best bet is to put a setuid C wrapper around
6714 =item You need to quote "%s"
6716 (W syntax) You assigned a bareword as a signal handler name.
6717 Unfortunately, you already have a subroutine of that name declared,
6718 which means that Perl 5 will try to call the subroutine when the
6719 assignment is executed, which is probably not what you want. (If it IS
6720 what you want, put an & in front.)
6722 =item Your random numbers are not that random
6724 (F) When trying to initialize the random seed for hashes, Perl could
6725 not get any randomness out of your system. This usually indicates
6726 Something Very Wrong.
6728 =item Zero length \N{} in regex; marked by S<<-- HERE> in m/%s/
6730 (F) Named Unicode character escapes C<(\N{...})> may return a zero-length
6731 sequence. Such an escape was used in an extended character class, i.e.
6732 C<(?[...])>, which is not permitted. Check that the correct escape has
6733 been used, and the correct charnames handler is in scope. The S<<-- HERE>
6734 shows whereabouts in the regular expression the problem was discovered.
6740 L<warnings>, L<perllexwarn>, L<diagnostics>.