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 Cannot compress integer in pack
566 (F) An argument to pack("w",...) was too large to compress. The BER
567 compressed integer format can only be used with positive integers, and you
568 attempted to compress Infinity or a very large number (> 1e308).
569 See L<perlfunc/pack>.
571 =item Cannot compress negative numbers in pack
573 (F) An argument to pack("w",...) was negative. The BER compressed integer
574 format can only be used with positive integers. See L<perlfunc/pack>.
576 =item Cannot convert a reference to %s to typeglob
578 (F) You manipulated Perl's symbol table directly, stored a reference
579 in it, then tried to access that symbol via conventional Perl syntax.
580 The access triggers Perl to autovivify that typeglob, but it there is
581 no legal conversion from that type of reference to a typeglob.
583 =item Cannot copy to %s
585 (P) Perl detected an attempt to copy a value to an internal type that cannot
586 be directly assigned to.
588 =item Cannot find encoding "%s"
590 (S io) You tried to apply an encoding that did not exist to a filehandle,
591 either with open() or binmode().
593 =item Cannot set tied @DB::args
595 (F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
596 is not supported. (Before this error was added, it used to crash.)
598 =item Cannot tie unreifiable array
600 (P) You somehow managed to call C<tie> on an array that does not
601 keep a reference count on its arguments and cannot be made to
602 do so. Such arrays are not even supposed to be accessible to
603 Perl code, but are only used internally.
605 =item Can only compress unsigned integers in pack
607 (F) An argument to pack("w",...) was not an integer. The BER compressed
608 integer format can only be used with positive integers, and you attempted
609 to compress something else. See L<perlfunc/pack>.
611 =item Can't bless non-reference value
613 (F) Only hard references may be blessed. This is how Perl "enforces"
614 encapsulation of objects. See L<perlobj>.
616 =item Can't "break" in a loop topicalizer
618 (F) You called C<break>, but you're in a C<foreach> block rather than
619 a C<given> block. You probably meant to use C<next> or C<last>.
621 =item Can't "break" outside a given block
623 (F) You called C<break>, but you're not inside a C<given> block.
625 =item Can't call method "%s" on an undefined value
627 (F) You used the syntax of a method call, but the slot filled by the
628 object reference or package name contains an undefined value. Something
629 like this will reproduce the error:
632 process $BADREF 1,2,3;
633 $BADREF->process(1,2,3);
635 =item Can't call method "%s" on unblessed reference
637 (F) A method call must know in what package it's supposed to run. It
638 ordinarily finds this out from the object reference you supply, but you
639 didn't supply an object reference in this case. A reference isn't an
640 object reference until it has been blessed. See L<perlobj>.
642 =item Can't call method "%s" without a package or object reference
644 (F) You used the syntax of a method call, but the slot filled by the
645 object reference or package name contains an expression that returns a
646 defined value which is neither an object reference nor a package name.
647 Something like this will reproduce the error:
650 process $BADREF 1,2,3;
651 $BADREF->process(1,2,3);
653 =item Can't call mro_isa_changed_in() on anonymous symbol table
655 (P) Perl got confused as to whether a hash was a plain hash or a
656 symbol table hash when trying to update @ISA caches.
658 =item Can't call mro_method_changed_in() on anonymous symbol table
660 (F) An XS module tried to call C<mro_method_changed_in> on a hash that was
661 not attached to the symbol table.
663 =item Can't chdir to %s
665 (F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
666 that you can chdir to, possibly because it doesn't exist.
668 =item Can't check filesystem of script "%s" for nosuid
670 (P) For some reason you can't check the filesystem of the script for
673 =item Can't coerce %s to %s in %s
675 (F) Certain types of SVs, in particular real symbol table entries
676 (typeglobs), can't be forced to stop being what they are. So you can't
686 but then $foo no longer contains a glob.
688 =item Can't "continue" outside a when block
690 (F) You called C<continue>, but you're not inside a C<when>
693 =item Can't create pipe mailbox
695 (P) An error peculiar to VMS. The process is suffering from exhausted
696 quotas or other plumbing problems.
698 =item Can't declare %s in "%s"
700 (F) Only scalar, array, and hash variables may be declared as "my", "our" or
701 "state" variables. They must have ordinary identifiers as names.
703 =item Can't "default" outside a topicalizer
705 (F) You have used a C<default> block that is neither inside a
706 C<foreach> loop nor a C<given> block. (Note that this error is
707 issued on exit from the C<default> block, so you won't get the
708 error if you use an explicit C<continue>.)
710 =item Can't do inplace edit: %s is not a regular file
712 (S inplace) You tried to use the B<-i> switch on a special file, such as
713 a file in /dev, a FIFO or an uneditable directory. The file was ignored.
715 =item Can't do inplace edit on %s: %s
717 (S inplace) The creation of the new file failed for the indicated
720 =item Can't do inplace edit without backup
722 (F) You're on a system such as MS-DOS that gets confused if you try
723 reading from a deleted (but still opened) file. You have to say
724 C<-i.bak>, or some such.
726 =item Can't do inplace edit: %s would not be unique
728 (S inplace) Your filesystem does not support filenames longer than 14
729 characters and Perl was unable to create a unique filename during
730 inplace editing with the B<-i> switch. The file was ignored.
732 =item Can't do waitpid with flags
734 (F) This machine doesn't have either waitpid() or wait4(), so only
735 waitpid() without flags is emulated.
737 =item Can't emulate -%s on #! line
739 (F) The #! line specifies a switch that doesn't make sense at this
740 point. For example, it'd be kind of silly to put a B<-x> on the #!
743 =item Can't %s %s-endian %ss on this platform
745 (F) Your platform's byte-order is neither big-endian nor little-endian,
746 or it has a very strange pointer size. Packing and unpacking big- or
747 little-endian floating point values and pointers may not be possible.
748 See L<perlfunc/pack>.
750 =item Can't exec "%s": %s
752 (W exec) A system(), exec(), or piped open call could not execute the
753 named program for the indicated reason. Typical reasons include: the
754 permissions were wrong on the file, the file wasn't found in
755 C<$ENV{PATH}>, the executable in question was compiled for another
756 architecture, or the #! line in a script points to an interpreter that
757 can't be run for similar reasons. (Or maybe your system doesn't support
762 (F) Perl was trying to execute the indicated program for you because
763 that's what the #! line said. If that's not what you wanted, you may
764 need to mention "perl" on the #! line somewhere.
766 =item Can't execute %s
768 (F) You used the B<-S> switch, but the copies of the script to execute
769 found in the PATH did not have correct permissions.
771 =item Can't find an opnumber for "%s"
773 (F) A string of a form C<CORE::word> was given to prototype(), but there
774 is no builtin with the name C<word>.
776 =item Can't find %s character property "%s"
778 (F) You used C<\p{}> or C<\P{}> but the character property by that name
779 could not be found. Maybe you misspelled the name of the property?
780 See L<perluniprops/Properties accessible through \p{} and \P{}>
781 for a complete list of available official properties.
783 =item Can't find label %s
785 (F) You said to goto a label that isn't mentioned anywhere that it's
786 possible for us to go to. See L<perlfunc/goto>.
788 =item Can't find %s on PATH
790 (F) You used the B<-S> switch, but the script to execute could not be
793 =item Can't find %s on PATH, '.' not in PATH
795 (F) You used the B<-S> switch, but the script to execute could not be
796 found in the PATH, or at least not with the correct permissions. The
797 script exists in the current directory, but PATH prohibits running it.
799 =item Can't find string terminator %s anywhere before EOF
801 (F) Perl strings can stretch over multiple lines. This message means
802 that the closing delimiter was omitted. Because bracketed quotes count
803 nesting levels, the following is missing its final parenthesis:
805 print q(The character '(' starts a side comment.);
807 If you're getting this error from a here-document, you may have
808 included unseen whitespace before or after your closing tag or there
809 may not be a linebreak after it. A good programmer's editor will have
810 a way to help you find these characters (or lack of characters). See
811 L<perlop> for the full details on here-documents.
813 =item Can't find Unicode property definition "%s"
815 (F) You may have tried to use C<\p> which means a Unicode
816 property (for example C<\p{Lu}> matches all uppercase
817 letters). If you did mean to use a Unicode property, see
818 L<perluniprops/Properties accessible through \p{} and \P{}>
819 for a complete list of available properties. If you didn't
820 mean to use a Unicode property, escape the C<\p>, either by
821 C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
826 (F) A fatal error occurred while trying to fork while opening a
829 =item Can't fork, trying again in 5 seconds
831 (W pipe) A fork in a piped open failed with EAGAIN and will be retried
834 =item Can't get filespec - stale stat buffer?
836 (S) A warning peculiar to VMS. This arises because of the difference
837 between access checks under VMS and under the Unix model Perl assumes.
838 Under VMS, access checks are done by filename, rather than by bits in
839 the stat buffer, so that ACLs and other protections can be taken into
840 account. Unfortunately, Perl assumes that the stat buffer contains all
841 the necessary information, and passes it, instead of the filespec, to
842 the access-checking routine. It will try to retrieve the filespec using
843 the device name and FID present in the stat buffer, but this works only
844 if you haven't made a subsequent call to the CRTL stat() routine,
845 because the device name is overwritten with each call. If this warning
846 appears, the name lookup failed, and the access-checking routine gave up
847 and returned FALSE, just to be conservative. (Note: The access-checking
848 routine knows about the Perl C<stat> operator and file tests, so you
849 shouldn't ever see this warning in response to a Perl command; it arises
850 only if some internal code takes stat buffers lightly.)
852 =item Can't get pipe mailbox device name
854 (P) An error peculiar to VMS. After creating a mailbox to act as a
855 pipe, Perl can't retrieve its name for later use.
857 =item Can't get SYSGEN parameter value for MAXBUF
859 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
860 mailbox buffers to be, and didn't get an answer.
862 =item Can't "goto" into the middle of a foreach loop
864 (F) A "goto" statement was executed to jump into the middle of a foreach
865 loop. You can't get there from here. See L<perlfunc/goto>.
867 =item Can't "goto" out of a pseudo block
869 (F) A "goto" statement was executed to jump out of what might look like
870 a block, except that it isn't a proper block. This usually occurs if
871 you tried to jump out of a sort() block or subroutine, which is a no-no.
872 See L<perlfunc/goto>.
874 =item Can't goto subroutine from an eval-%s
876 (F) The "goto subroutine" call can't be used to jump out of an eval
879 =item Can't goto subroutine from a sort sub (or similar callback)
881 (F) The "goto subroutine" call can't be used to jump out of the
882 comparison sub for a sort(), or from a similar callback (such
883 as the reduce() function in List::Util).
885 =item Can't goto subroutine outside a subroutine
887 (F) The deeply magical "goto subroutine" call can only replace one
888 subroutine call for another. It can't manufacture one out of whole
889 cloth. In general you should be calling it out of only an AUTOLOAD
890 routine anyway. See L<perlfunc/goto>.
892 =item Can't ignore signal CHLD, forcing to default
894 (W signal) Perl has detected that it is being run with the SIGCHLD
895 signal (sometimes known as SIGCLD) disabled. Since disabling this
896 signal will interfere with proper determination of exit status of child
897 processes, Perl has reset the signal to its default value. This
898 situation typically indicates that the parent program under which Perl
899 may be running (e.g. cron) is being very careless.
901 =item Can't kill a non-numeric process ID
903 (F) Process identifiers must be (signed) integers. It is a fatal error to
904 attempt to kill() an undefined, empty-string or otherwise non-numeric
907 =item Can't "last" outside a loop block
909 (F) A "last" statement was executed to break out of the current block,
910 except that there's this itty bitty problem called there isn't a current
911 block. Note that an "if" or "else" block doesn't count as a "loopish"
912 block, as doesn't a block given to sort(), map() or grep(). You can
913 usually double the curlies to get the same effect though, because the
914 inner curlies will be considered a block that loops once. See
917 =item Can't linearize anonymous symbol table
919 (F) Perl tried to calculate the method resolution order (MRO) of a
920 package, but failed because the package stash has no name.
922 =item Can't load '%s' for module %s
924 (F) The module you tried to load failed to load a dynamic extension.
925 This may either mean that you upgraded your version of perl to one
926 that is incompatible with your old dynamic extensions (which is known
927 to happen between major versions of perl), or (more likely) that your
928 dynamic extension was built against an older version of the library
929 that is installed on your system. You may need to rebuild your old
932 =item Can't localize lexical variable %s
934 (F) You used local on a variable name that was previously declared as a
935 lexical variable using "my" or "state". This is not allowed. If you
936 want to localize a package variable of the same name, qualify it with
939 =item Can't localize through a reference
941 (F) You said something like C<local $$ref>, which Perl can't currently
942 handle, because when it goes to restore the old value of whatever $ref
943 pointed to after the scope of the local() is finished, it can't be sure
944 that $ref will still be a reference.
946 =item Can't locate %s
948 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
949 Perl looks for the file in all the locations mentioned in @INC, unless
950 the file name included the full path to the file. Perhaps you need
951 to set the PERL5LIB or PERL5OPT environment variable to say where the
952 extra library is, or maybe the script needs to add the library name
953 to @INC. Or maybe you just misspelled the name of the file. See
954 L<perlfunc/require> and L<lib>.
956 =item Can't locate auto/%s.al in @INC
958 (F) A function (or method) was called in a package which allows
959 autoload, but there is no function to autoload. Most probable causes
960 are a misprint in a function/method name or a failure to C<AutoSplit>
961 the file, say, by doing C<make install>.
963 =item Can't locate loadable object for module %s in @INC
965 (F) The module you loaded is trying to load an external library, like
966 for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
967 unable to locate this library. See L<DynaLoader>.
969 =item Can't locate object method "%s" via package "%s"
971 (F) You called a method correctly, and it correctly indicated a package
972 functioning as a class, but that package doesn't define that particular
973 method, nor does any of its base classes. See L<perlobj>.
975 =item Can't locate package %s for @%s::ISA
977 (W syntax) The @ISA array contained the name of another package that
978 doesn't seem to exist.
980 =item Can't locate PerlIO%s
982 (F) You tried to use in open() a PerlIO layer that does not exist,
983 e.g. open(FH, ">:nosuchlayer", "somefile").
985 =item Can't make list assignment to %ENV on this system
987 (F) List assignment to %ENV is not supported on some systems, notably
990 =item Can't make loaded symbols global on this platform while loading %s
992 (S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
993 that symbols from the stated file are made available globally within the
994 process, but that functionality is not available on this platform. Whilst
995 the module likely will still work, this may prevent the perl interpreter
996 from loading other XS-based extensions which need to link directly to
997 functions defined in the C or XS code in the stated file.
999 =item Can't modify %s in %s
1001 (F) You aren't allowed to assign to the item indicated, or otherwise try
1002 to change it, such as with an auto-increment.
1004 =item Can't modify nonexistent substring
1006 (P) The internal routine that does assignment to a substr() was handed
1009 =item Can't modify non-lvalue subroutine call
1011 (F) Subroutines meant to be used in lvalue context should be declared as
1012 such. See L<perlsub/"Lvalue subroutines">.
1014 =item Can't msgrcv to read-only var
1016 (F) The target of a msgrcv must be modifiable to be used as a receive
1019 =item Can't "next" outside a loop block
1021 (F) A "next" statement was executed to reiterate the current block, but
1022 there isn't a current block. Note that an "if" or "else" block doesn't
1023 count as a "loopish" block, as doesn't a block given to sort(), map() or
1024 grep(). You can usually double the curlies to get the same effect
1025 though, because the inner curlies will be considered a block that loops
1026 once. See L<perlfunc/next>.
1030 (F) You tried to run a perl built with MAD support with
1031 the PERL_XMLDUMP environment variable set, but the file
1032 named by that variable could not be opened.
1034 =item Can't open %s: %s
1036 (S inplace) The implicit opening of a file through use of the C<< <> >>
1037 filehandle, either implicitly under the C<-n> or C<-p> command-line
1038 switches, or explicitly, failed for the indicated reason. Usually
1039 this is because you don't have read permission for a file which
1040 you named on the command line.
1042 (F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1043 your operating system's equivalent) could not be opened.
1045 =item Can't open a reference
1047 (W io) You tried to open a scalar reference for reading or writing,
1048 using the 3-arg open() syntax:
1052 but your version of perl is compiled without perlio, and this form of
1053 open is not supported.
1055 =item Can't open bidirectional pipe
1057 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1058 You can try any of several modules in the Perl library to do this, such
1059 as IPC::Open2. Alternately, direct the pipe's output to a file using
1060 ">", and then read it in under a different file handle.
1062 =item Can't open error file %s as stderr
1064 (F) An error peculiar to VMS. Perl does its own command line
1065 redirection, and couldn't open the file specified after '2>' or '2>>' on
1066 the command line for writing.
1068 =item Can't open input file %s as stdin
1070 (F) An error peculiar to VMS. Perl does its own command line
1071 redirection, and couldn't open the file specified after '<' on the
1072 command line for reading.
1074 =item Can't open output file %s as stdout
1076 (F) An error peculiar to VMS. Perl does its own command line
1077 redirection, and couldn't open the file specified after '>' or '>>' on
1078 the command line for writing.
1080 =item Can't open output pipe (name: %s)
1082 (P) An error peculiar to VMS. Perl does its own command line
1083 redirection, and couldn't open the pipe into which to send data destined
1086 =item Can't open perl script "%s": %s
1088 (F) The script you specified can't be opened for the indicated reason.
1090 If you're debugging a script that uses #!, and normally relies on the
1091 shell's $PATH search, the -S option causes perl to do that search, so
1092 you don't have to type the path or C<`which $scriptname`>.
1094 =item Can't read CRTL environ
1096 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1097 from the CRTL's internal environment array and discovered the array was
1098 missing. You need to figure out where your CRTL misplaced its environ
1099 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1102 =item Can't "redo" outside a loop block
1104 (F) A "redo" statement was executed to restart the current block, but
1105 there isn't a current block. Note that an "if" or "else" block doesn't
1106 count as a "loopish" block, as doesn't a block given to sort(), map()
1107 or grep(). You can usually double the curlies to get the same effect
1108 though, because the inner curlies will be considered a block that
1109 loops once. See L<perlfunc/redo>.
1111 =item Can't remove %s: %s, skipping file
1113 (S inplace) You requested an inplace edit without creating a backup
1114 file. Perl was unable to remove the original file to replace it with
1115 the modified file. The file was left unmodified.
1117 =item Can't rename %s to %s: %s, skipping file
1119 (S inplace) The rename done by the B<-i> switch failed for some reason,
1120 probably because you don't have write permission to the directory.
1122 =item Can't reopen input pipe (name: %s) in binary mode
1124 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1125 to reopen it to accept binary data. Alas, it failed.
1127 =item Can't reset %ENV on this system
1129 (F) You called C<reset('E')> or similar, which tried to reset
1130 all variables in the current package beginning with "E". In
1131 the main package, that includes %ENV. Resetting %ENV is not
1132 supported on some systems, notably VMS.
1134 =item Can't resolve method "%s" overloading "%s" in package "%s"
1136 (F)(P) Error resolving overloading specified by a method name (as
1137 opposed to a subroutine reference): no such method callable via the
1138 package. If the method name is C<???>, this is an internal error.
1140 =item Can't return %s from lvalue subroutine
1142 (F) Perl detected an attempt to return illegal lvalues (such as
1143 temporary or readonly values) from a subroutine used as an lvalue. This
1146 =item Can't return outside a subroutine
1148 (F) The return statement was executed in mainline code, that is, where
1149 there was no subroutine call to return out of. See L<perlsub>.
1151 =item Can't return %s to lvalue scalar context
1153 (F) You tried to return a complete array or hash from an lvalue
1154 subroutine, but you called the subroutine in a way that made Perl
1155 think you meant to return only one value. You probably meant to
1156 write parentheses around the call to the subroutine, which tell
1157 Perl that the call should be in list context.
1159 =item Can't stat script "%s"
1161 (P) For some reason you can't fstat() the script even though you have it
1162 open already. Bizarre.
1164 =item Can't take log of %g
1166 (F) For ordinary real numbers, you can't take the logarithm of a
1167 negative number or zero. There's a Math::Complex package that comes
1168 standard with Perl, though, if you really want to do that for the
1171 =item Can't take sqrt of %g
1173 (F) For ordinary real numbers, you can't take the square root of a
1174 negative number. There's a Math::Complex package that comes standard
1175 with Perl, though, if you really want to do that.
1177 =item Can't undef active subroutine
1179 (F) You can't undefine a routine that's currently running. You can,
1180 however, redefine it while it's running, and you can even undef the
1181 redefined subroutine while the old routine is running. Go figure.
1183 =item Can't upgrade %s (%d) to %d
1185 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1186 into a more specialized kind of SV. The top several SV types are so
1187 specialized, however, that they cannot be interconverted. This message
1188 indicates that such a conversion was attempted.
1190 =item Can't use '%c' after -mname
1192 (F) You tried to call perl with the B<-m> switch, but you put something
1193 other than "=" after the module name.
1195 =item Can't use anonymous symbol table for method lookup
1197 (F) The internal routine that does method lookup was handed a symbol
1198 table that doesn't have a name. Symbol tables can become anonymous
1199 for example by undefining stashes: C<undef %Some::Package::>.
1201 =item Can't use an undefined value as %s reference
1203 (F) A value used as either a hard reference or a symbolic reference must
1204 be a defined value. This helps to delurk some insidious errors.
1206 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1208 (F) Only hard references are allowed by "strict refs". Symbolic
1209 references are disallowed. See L<perlref>.
1211 =item Can't use %! because Errno.pm is not available
1213 (F) The first time the C<%!> hash is used, perl automatically loads the
1214 Errno.pm module. The Errno module is expected to tie the %! hash to
1215 provide symbolic names for C<$!> errno values.
1217 =item Can't use both '<' and '>' after type '%c' in %s
1219 (F) A type cannot be forced to have both big-endian and little-endian
1220 byte-order at the same time, so this combination of modifiers is not
1221 allowed. See L<perlfunc/pack>.
1223 =item Can't use %s for loop variable
1225 (F) Only a simple scalar variable may be used as a loop variable on a
1228 =item Can't use global %s in "%s"
1230 (F) You tried to declare a magical variable as a lexical variable. This
1231 is not allowed, because the magic can be tied to only one location
1232 (namely the global variable) and it would be incredibly confusing to
1233 have variables in your program that looked like magical variables but
1236 =item Can't use '%c' in a group with different byte-order in %s
1238 (F) You attempted to force a different byte-order on a type
1239 that is already inside a group with a byte-order modifier.
1240 For example you cannot force little-endianness on a type that
1241 is inside a big-endian group.
1243 =item Can't use "my %s" in sort comparison
1245 (F) The global variables $a and $b are reserved for sort comparisons.
1246 You mentioned $a or $b in the same line as the <=> or cmp operator,
1247 and the variable had earlier been declared as a lexical variable.
1248 Either qualify the sort variable with the package name, or rename the
1251 =item Can't use %s ref as %s ref
1253 (F) You've mixed up your reference types. You have to dereference a
1254 reference of the type needed. You can use the ref() function to
1255 test the type of the reference, if need be.
1257 =item Can't use string ("%s") as %s ref while "strict refs" in use
1259 =item Can't use string ("%s"...) as %s ref while "strict refs" in use
1261 (F) You've told Perl to dereference a string, something which
1262 C<use strict> blocks to prevent it happening accidentally. See
1263 L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1264 in a double-quoted string immediately before interpolating a variable,
1265 for example in C<"user @$twitter_id">, which says to treat the contents
1266 of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1267 symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
1269 =item Can't use subscript on %s
1271 (F) The compiler tried to interpret a bracketed expression as a
1272 subscript. But to the left of the brackets was an expression that
1273 didn't look like a hash or array reference, or anything else subscriptable.
1275 =item Can't use \%c to mean $%c in expression
1277 (W syntax) In an ordinary expression, backslash is a unary operator that
1278 creates a reference to its argument. The use of backslash to indicate a
1279 backreference to a matched substring is valid only as part of a regular
1280 expression pattern. Trying to do this in ordinary Perl code produces a
1281 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1284 =item Can't weaken a nonreference
1286 (F) You attempted to weaken something that was not a reference. Only
1287 references can be weakened.
1289 =item Can't "when" outside a topicalizer
1291 (F) You have used a when() block that is neither inside a C<foreach>
1292 loop nor a C<given> block. (Note that this error is issued on exit
1293 from the C<when> block, so you won't get the error if the match fails,
1294 or if you use an explicit C<continue>.)
1296 =item Can't x= to read-only value
1298 (F) You tried to repeat a constant value (often the undefined value)
1299 with an assignment operator, which implies modifying the value itself.
1300 Perhaps you need to copy the value to a temporary, and repeat that.
1302 =item Character following "\c" must be ASCII
1304 (F)(D deprecated, syntax) In C<\cI<X>>, I<X> must be an ASCII character.
1305 It is planned to make this fatal in all instances in Perl v5.20. In
1306 the cases where it isn't fatal, the character this evaluates to is
1307 derived by exclusive or'ing the code point of this character with 0x40.
1309 Note that non-alphabetic ASCII characters are discouraged here as well,
1310 and using non-printable ones will be deprecated starting in v5.18.
1312 =item Character in 'C' format wrapped in pack
1318 where $x is either less than 0 or more than 255; the C<"C"> format is
1319 only for encoding native operating system characters (ASCII, EBCDIC,
1320 and so on) and not for Unicode characters, so Perl behaved as if you meant
1324 If you actually want to pack Unicode codepoints, use the C<"U"> format
1327 =item Character in 'c' format wrapped in pack
1333 where $x is either less than -128 or more than 127; the C<"c"> format
1334 is only for encoding native operating system characters (ASCII, EBCDIC,
1335 and so on) and not for Unicode characters, so Perl behaved as if you meant
1337 pack("c", $x & 255);
1339 If you actually want to pack Unicode codepoints, use the C<"U"> format
1342 =item Character in '%c' format wrapped in unpack
1344 (W unpack) You tried something like
1346 unpack("H", "\x{2a1}")
1348 where the format expects to process a byte (a character with a value
1349 below 256), but a higher value was provided instead. Perl uses the
1350 value modulus 256 instead, as if you had provided:
1352 unpack("H", "\x{a1}")
1354 =item Character in 'W' format wrapped in pack
1360 where $x is either less than 0 or more than 255. However, C<U0>-mode
1361 expects all values to fall in the interval [0, 255], so Perl behaved
1364 pack("U0W", $x & 255)
1366 =item Character(s) in '%c' format wrapped in pack
1368 (W pack) You tried something like
1370 pack("u", "\x{1f3}b")
1372 where the format expects to process a sequence of bytes (character with a
1373 value below 256), but some of the characters had a higher value. Perl
1374 uses the character values modulus 256 instead, as if you had provided:
1376 pack("u", "\x{f3}b")
1378 =item Character(s) in '%c' format wrapped in unpack
1380 (W unpack) You tried something like
1382 unpack("s", "\x{1f3}b")
1384 where the format expects to process a sequence of bytes (character with a
1385 value below 256), but some of the characters had a higher value. Perl
1386 uses the character values modulus 256 instead, as if you had provided:
1388 unpack("s", "\x{f3}b")
1390 =item "\c{" is deprecated and is more clearly written as ";"
1392 (D deprecated, syntax) The C<\cI<X>> construct is intended to be a way
1393 to specify non-printable characters. You used it with a "{" which
1394 evaluates to ";", which is printable. It is planned to remove the
1395 ability to specify a semi-colon this way in Perl 5.20. Just use a
1396 semi-colon or a backslash-semi-colon without the "\c".
1398 =item "\c%c" is more clearly written simply as "%s"
1400 (W syntax) The C<\cI<X>> construct is intended to be a way to specify
1401 non-printable characters. You used it for a printable one, which is better
1402 written as simply itself, perhaps preceded by a backslash for non-word
1405 =item Cloning substitution context is unimplemented
1407 (F) Creating a new thread inside the C<s///> operator is not supported.
1409 =item closedir() attempted on invalid dirhandle %s
1411 (W io) The dirhandle you tried to close is either closed or not really
1412 a dirhandle. Check your control flow.
1414 =item close() on unopened filehandle %s
1416 (W unopened) You tried to close a filehandle that was never opened.
1418 =item Closure prototype called
1420 (F) If a closure has attributes, the subroutine passed to an attribute
1421 handler is the prototype that is cloned when a new closure is created.
1422 This subroutine cannot be called.
1424 =item Code missing after '/'
1426 (F) You had a (sub-)template that ends with a '/'. There must be
1427 another template code following the slash. See L<perlfunc/pack>.
1429 =item Code point 0x%X is not Unicode, may not be portable
1431 (S non_unicode) You had a code point above the Unicode maximum
1434 Perl allows strings to contain a superset of Unicode code points, up
1435 to the limit of what is storable in an unsigned integer on your system,
1436 but these may not be accepted by other languages/systems. At one time,
1437 it was legal in some standards to have code points up to 0x7FFF_FFFF,
1438 but not higher. Code points above 0xFFFF_FFFF require larger than a
1441 =item %s: Command not found
1443 (A) You've accidentally run your script through B<csh> or another shell
1444 shell instead of Perl. Check the #! line, or manually feed your script
1445 into Perl yourself. The #! line at the top of your file could look like
1449 =item Compilation failed in require
1451 (F) Perl could not compile a file specified in a C<require> statement.
1452 Perl uses this generic message when none of the errors that it
1453 encountered were severe enough to halt compilation immediately.
1455 =item Complex regular subexpression recursion limit (%d) exceeded
1457 (W regexp) The regular expression engine uses recursion in complex
1458 situations where back-tracking is required. Recursion depth is limited
1459 to 32766, or perhaps less in architectures where the stack cannot grow
1460 arbitrarily. ("Simple" and "medium" situations are handled without
1461 recursion and are not subject to a limit.) Try shortening the string
1462 under examination; looping in Perl code (e.g. with C<while>) rather than
1463 in the regular expression engine; or rewriting the regular expression so
1464 that it is simpler or backtracks less. (See L<perlfaq2> for information
1465 on I<Mastering Regular Expressions>.)
1467 =item connect() on closed socket %s
1469 (W closed) You tried to do a connect on a closed socket. Did you forget
1470 to check the return value of your socket() call? See
1471 L<perlfunc/connect>.
1473 =item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1475 (F) The subroutine registered to handle constant overloading
1476 (see L<overload>) or a custom charnames handler (see
1477 L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1479 =item Constant(%s): $^H{%s} is not defined
1481 (F) The parser found inconsistencies while attempting to define an
1482 overloaded constant. Perhaps you forgot to load the corresponding
1483 L<overload> pragma?.
1485 =item Constant is not %s reference
1487 (F) A constant value (perhaps declared using the C<use constant> pragma)
1488 is being dereferenced, but it amounts to the wrong type of reference.
1489 The message indicates the type of reference that was expected. This
1490 usually indicates a syntax error in dereferencing the constant value.
1491 See L<perlsub/"Constant Functions"> and L<constant>.
1493 =item Constant subroutine %s redefined
1495 (W redefine)(S) You redefined a subroutine which had previously
1496 been eligible for inlining. See L<perlsub/"Constant Functions">
1497 for commentary and workarounds.
1499 =item Constant subroutine %s undefined
1501 (W misc) You undefined a subroutine which had previously been eligible
1502 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1505 =item Constant(%s) unknown
1507 (F) The parser found inconsistencies either while attempting
1508 to define an overloaded constant, or when trying to find the
1509 character name specified in the C<\N{...}> escape. Perhaps you
1510 forgot to load the corresponding L<overload> pragma?.
1512 =item Copy method did not return a reference
1514 (F) The method which overloads "=" is buggy. See
1515 L<overload/Copy Constructor>.
1517 =item &CORE::%s cannot be called directly
1519 (F) You tried to call a subroutine in the C<CORE::> namespace
1520 with C<&foo> syntax or through a reference. Some subroutines
1521 in this package cannot yet be called that way, but must be
1522 called as barewords. Something like this will work:
1524 BEGIN { *shove = \&CORE::push; }
1525 shove @array, 1,2,3; # pushes on to @array
1527 =item CORE::%s is not a keyword
1529 (F) The CORE:: namespace is reserved for Perl keywords.
1531 =item Corrupted regexp opcode %d > %d
1533 (P) This is either an error in Perl, or, if you're using
1534 one, your L<custom regular expression engine|perlreapi>. If not the
1535 latter, report the problem through the L<perlbug> utility.
1537 =item corrupted regexp pointers
1539 (P) The regular expression engine got confused by what the regular
1540 expression compiler gave it.
1542 =item corrupted regexp program
1544 (P) The regular expression engine got passed a regexp program without a
1547 =item Corrupt malloc ptr 0x%x at 0x%x
1549 (P) The malloc package that comes with Perl had an internal failure.
1551 =item Count after length/code in unpack
1553 (F) You had an unpack template indicating a counted-length string, but
1554 you have also specified an explicit size for the string. See
1558 The following are used in lib/diagnostics.t for testing two =items that
1559 share the same description. Changes here need to be propagated to there
1561 =item Deep recursion on anonymous subroutine
1563 =item Deep recursion on subroutine "%s"
1565 (W recursion) This subroutine has called itself (directly or indirectly)
1566 100 times more than it has returned. This probably indicates an
1567 infinite recursion, unless you're writing strange benchmark programs, in
1568 which case it indicates something else.
1570 This threshold can be changed from 100, by recompiling the F<perl> binary,
1571 setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1573 =item defined(@array) is deprecated
1575 (D deprecated) defined() is not usually useful on arrays because it
1576 checks for an undefined I<scalar> value. If you want to see if the
1577 array is empty, just use C<if (@array) { # not empty }> for example.
1579 =item defined(%hash) is deprecated
1581 (D deprecated) C<defined()> is not usually right on hashes and has been
1582 discouraged since 5.004.
1584 Although C<defined %hash> is false on a plain not-yet-used hash, it
1585 becomes true in several non-obvious circumstances, including iterators,
1586 weak references, stash names, even remaining true after C<undef %hash>.
1587 These things make C<defined %hash> fairly useless in practice.
1589 If a check for non-empty is what you wanted then just put it in boolean
1590 context (see L<perldata/Scalar values>):
1596 If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1597 variable exists then that's never really been reliable, and isn't
1598 a good way to enquire about the features of a package, or whether
1602 =item (?(DEFINE)....) does not allow branches in regex; marked by
1603 S<<-- HERE> in m/%s/
1605 (F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
1606 most likely cause of this error is that you left out a parenthesis inside
1607 of the C<....> part.
1609 The <-- HERE shows whereabouts in the regular expression the problem was
1612 =item %s defines neither package nor VERSION--version check failed
1614 (F) You said something like "use Module 42" but in the Module file
1615 there are neither package declarations nor a C<$VERSION>.
1617 =item delete argument is index/value array slice, use array slice
1619 (F) You used index/value array slice syntax (C<%array[...]>) as
1620 the argument to C<delete>. You probably meant C<@array[...]> with
1621 an @ symbol instead.
1623 =item delete argument is key/value hash slice, use hash slice
1625 (F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1626 C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1628 =item delete argument is not a HASH or ARRAY element or slice
1630 (F) The argument to C<delete> must be either a hash or array element,
1636 or a hash or array slice, such as:
1638 @foo[$bar, $baz, $xyzzy]
1639 @{$ref->[12]}{"susie", "queue"}
1641 =item Delimiter for here document is too long
1643 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1644 long for Perl to handle. You have to be seriously twisted to write code
1645 that triggers this error.
1647 =item Deprecated use of my() in false conditional
1649 (D deprecated) You used a declaration similar to C<my $x if 0>. There
1650 has been a long-standing bug in Perl that causes a lexical variable
1651 not to be cleared at scope exit when its declaration includes a false
1652 conditional. Some people have exploited this bug to achieve a kind of
1653 static variable. Since we intend to fix this bug, we don't want people
1654 relying on this behavior. You can achieve a similar static effect by
1655 declaring the variable in a separate block outside the function, eg
1657 sub f { my $x if 0; return $x++ }
1661 { my $x; sub f { return $x++ } }
1663 Beginning with perl 5.9.4, you can also use C<state> variables to have
1664 lexicals that are initialized only once (see L<feature>):
1666 sub f { state $x; return $x++ }
1668 =item DESTROY created new reference to dead object '%s'
1670 (F) A DESTROY() method created a new reference to the object which is
1671 just being DESTROYed. Perl is confused, and prefers to abort rather
1672 than to create a dangling reference.
1674 =item Did not produce a valid header
1678 =item %s did not return a true value
1680 (F) A required (or used) file must return a true value to indicate that
1681 it compiled correctly and ran its initialization code correctly. It's
1682 traditional to end such a file with a "1;", though any true value would
1683 do. See L<perlfunc/require>.
1685 =item (Did you mean &%s instead?)
1687 (W misc) You probably referred to an imported subroutine &FOO as $FOO or
1690 =item (Did you mean "local" instead of "our"?)
1692 (W misc) Remember that "our" does not localize the declared global
1693 variable. You have declared it again in the same lexical scope, which
1696 =item (Did you mean $ or @ instead of %?)
1698 (W) You probably said %hash{$key} when you meant $hash{$key} or
1699 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1704 (F) You passed die() an empty string (the equivalent of C<die "">) or
1705 you called it with no args and C<$@> was empty.
1707 =item Document contains no data
1711 =item %s does not define %s::VERSION--version check failed
1713 (F) You said something like "use Module 42" but the Module did not
1714 define a C<$VERSION>.
1716 =item '/' does not take a repeat count
1718 (F) You cannot put a repeat count of any kind right after the '/' code.
1719 See L<perlfunc/pack>.
1721 =item Don't know how to get file name
1723 (P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1724 somehow called on another platform. This should not happen.
1726 =item Don't know how to handle magic of type \%o
1728 (P) The internal handling of magical variables has been cursed.
1730 =item do_study: out of memory
1732 (P) This should have been caught by safemalloc() instead.
1734 =item (Do you need to predeclare %s?)
1736 (S syntax) This is an educated guess made in conjunction with the message
1737 "%s found where operator expected". It often means a subroutine or module
1738 name is being referenced that hasn't been declared yet. This may be
1739 because of ordering problems in your file, or because of a missing
1740 "sub", "package", "require", or "use" statement. If you're referencing
1741 something that isn't defined yet, you don't actually have to define the
1742 subroutine or package before the current location. You can use an empty
1743 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1745 =item dump() better written as CORE::dump()
1747 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1748 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1750 =item dump is not supported
1752 (F) Your machine doesn't support dump/undump.
1754 =item Duplicate free() ignored
1756 (S malloc) An internal routine called free() on something that had
1759 =item Duplicate modifier '%c' after '%c' in %s
1761 (W unpack) You have applied the same modifier more than once after a
1762 type in a pack template. See L<perlfunc/pack>.
1764 =item each on reference is experimental
1766 (S experimental::autoderef) C<each> with a scalar argument is experimental
1767 and may change or be removed in a future Perl version. If you want to
1768 take the risk of using this feature, simply disable this warning:
1770 no warnings "experimental::autoderef";
1772 =item elseif should be elsif
1774 (S syntax) There is no keyword "elseif" in Perl because Larry thinks
1775 it's ugly. Your code will be interpreted as an attempt to call a method
1776 named "elseif" for the class returned by the following block. This is
1777 unlikely to be what you want.
1779 =item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
1781 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1782 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1783 a regular expression without specifying the property name.
1785 =item entering effective %s failed
1787 (F) While under the C<use filetest> pragma, switching the real and
1788 effective uids or gids failed.
1790 =item %ENV is aliased to %s
1792 (F) You're running under taint mode, and the C<%ENV> variable has been
1793 aliased to another hash, so it doesn't reflect anymore the state of the
1794 program's environment. This is potentially insecure.
1796 =item Error converting file specification %s
1798 (F) An error peculiar to VMS. Because Perl may have to deal with file
1799 specifications in either VMS or Unix syntax, it converts them to a
1800 single form when it must operate on them directly. Either you've passed
1801 an invalid file specification to Perl, or you've found a case the
1802 conversion routines don't handle. Drat.
1804 =item Escape literal pattern white space under /x
1806 (D deprecated) You compiled a regular expression pattern with C</x> to
1807 ignore white space, and you used, as a literal, one of the characters
1808 that Perl plans to eventually treat as white space. The character must
1809 be escaped somehow, or it will work differently on a future Perl that
1810 does treat it as white space. The easiest way is to insert a backslash
1811 immediately before it, or to enclose it with square brackets. This
1812 change is to bring Perl into conformance with Unicode recommendations.
1813 Here are the five characters that generate this warning:
1815 U+200E LEFT-TO-RIGHT MARK,
1816 U+200F RIGHT-TO-LEFT MARK,
1817 U+2028 LINE SEPARATOR,
1819 U+2029 PARAGRAPH SEPARATOR.
1821 =item Eval-group in insecure regular expression
1823 (F) Perl detected tainted data when trying to compile a regular
1824 expression that contains the C<(?{ ... })> zero-width assertion, which
1825 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1827 =item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
1829 (F) Perl tried to compile a regular expression containing the
1830 C<(?{ ... })> zero-width assertion at run time, as it would when the
1831 pattern contains interpolated values. Since that is a security risk,
1832 it is not allowed. If you insist, you may still do this by using the
1833 C<re 'eval'> pragma or by explicitly building the pattern from an
1834 interpolated string at run time and using that in an eval(). See
1835 L<perlre/(?{ code })>.
1837 =item Eval-group not allowed, use re 'eval' in regex m/%s/
1839 (F) A regular expression contained the C<(?{ ... })> zero-width
1840 assertion, but that construct is only allowed when the C<use re 'eval'>
1841 pragma is in effect. See L<perlre/(?{ code })>.
1843 =item EVAL without pos change exceeded limit in regex; marked by
1844 S<<-- HERE> in m/%s/
1846 (F) You used a pattern that nested too many EVAL calls without consuming
1847 any text. Restructure the pattern so that text is consumed.
1849 The <-- HERE shows whereabouts in the regular expression the problem was
1852 =item Excessively long <> operator
1854 (F) The contents of a <> operator may not exceed the maximum size of a
1855 Perl identifier. If you're just trying to glob a long list of
1856 filenames, try using the glob() operator, or put the filenames into a
1857 variable and glob that.
1859 =item exec? I'm not *that* kind of operating system
1861 (F) The C<exec> function is not implemented on some systems, e.g., Symbian
1862 OS. See L<perlport>.
1864 =item Execution of %s aborted due to compilation errors.
1866 (F) The final summary message when a Perl compilation fails.
1868 =item exists argument is not a HASH or ARRAY element or a subroutine
1870 (F) The argument to C<exists> must be a hash or array element or a
1871 subroutine with an ampersand, such as:
1877 =item exists argument is not a subroutine name
1879 (F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1880 and not a subroutine call. C<exists &sub()> will generate this error.
1882 =item Exiting eval via %s
1884 (W exiting) You are exiting an eval by unconventional means, such as a
1885 goto, or a loop control statement.
1887 =item Exiting format via %s
1889 (W exiting) You are exiting a format by unconventional means, such as a
1890 goto, or a loop control statement.
1892 =item Exiting pseudo-block via %s
1894 (W exiting) You are exiting a rather special block construct (like a
1895 sort block or subroutine) by unconventional means, such as a goto, or a
1896 loop control statement. See L<perlfunc/sort>.
1898 =item Exiting subroutine via %s
1900 (W exiting) You are exiting a subroutine by unconventional means, such
1901 as a goto, or a loop control statement.
1903 =item Exiting substitution via %s
1905 (W exiting) You are exiting a substitution by unconventional means, such
1906 as a return, a goto, or a loop control statement.
1908 =item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
1910 (F) You wrote something like
1914 to denote a capturing group of the form
1915 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1916 but omitted the C<")">.
1918 =item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
1920 (F) The C<(?[...])> extended character class regular expression construct
1921 only allows character classes (including character class escapes like
1922 C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1923 containing at least one flag and exactly one C<(?[...])> construct.
1924 This allows a regular expression containing just C<(?[...])> to be
1925 interpolated. If you see this error message, then you probably
1926 have some other C<(?...)> construct inside your character class. See
1927 L<perlrecharclass/Extended Bracketed Character Classes>.
1929 =item Experimental "%s" subs not enabled
1931 (F) To use lexical subs, you must first enable them:
1933 no warnings 'experimental::lexical_subs';
1934 use feature 'lexical_subs';
1937 =item Explicit blessing to '' (assuming package main)
1939 (W misc) You are blessing a reference to a zero length string. This has
1940 the effect of blessing the reference into the package main. This is
1941 usually not what you want. Consider providing a default target package,
1942 e.g. bless($ref, $p || 'MyPackage');
1944 =item %s: Expression syntax
1946 (A) You've accidentally run your script through B<csh> instead of Perl.
1947 Check the #! line, or manually feed your script into Perl yourself.
1949 =item %s failed--call queue aborted
1951 (F) An untrapped exception was raised while executing a UNITCHECK,
1952 CHECK, INIT, or END subroutine. Processing of the remainder of the
1953 queue of such routines has been prematurely ended.
1955 =item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
1957 (W regexp)(F) A character class range must start and end at a literal
1958 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1959 in your false range is interpreted as a literal "-". In a C<(?[...])>
1960 construct, this is an error, rather than a warning. Consider quoting
1961 the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
1962 the problem was discovered. See L<perlre>.
1964 =item Fatal VMS error (status=%d) at %s, line %d
1966 (P) An error peculiar to VMS. Something untoward happened in a VMS
1967 system service or RTL routine; Perl's exit status should provide more
1968 details. The filename in "at %s" and the line number in "line %d" tell
1969 you which section of the Perl source code is distressed.
1971 =item fcntl is not implemented
1973 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1974 PDP-11 or something?
1976 =item FETCHSIZE returned a negative value
1978 (F) A tied array claimed to have a negative number of elements, which
1981 =item Field too wide in 'u' format in pack
1983 (W pack) Each line in an uuencoded string starts with a length indicator
1984 which can't encode values above 63. So there is no point in asking for
1985 a line length bigger than that. Perl will behave as if you specified
1986 C<u63> as the format.
1988 =item Filehandle %s opened only for input
1990 (W io) You tried to write on a read-only filehandle. If you intended
1991 it to be a read-write filehandle, you needed to open it with "+<" or
1992 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1993 write the file, use ">" or ">>". See L<perlfunc/open>.
1995 =item Filehandle %s opened only for output
1997 (W io) You tried to read from a filehandle opened only for writing, If
1998 you intended it to be a read/write filehandle, you needed to open it
1999 with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2000 read from the file, use "<". See L<perlfunc/open>. Another possibility
2001 is that you attempted to open filedescriptor 0 (also known as STDIN) for
2002 output (maybe you closed STDIN earlier?).
2004 =item Filehandle %s reopened as %s only for input
2006 (W io) You opened for reading a filehandle that got the same filehandle id
2007 as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
2010 =item Filehandle STDIN reopened as %s only for output
2012 (W io) You opened for writing a filehandle that got the same filehandle id
2013 as STDIN. This occurred because you closed STDIN previously.
2015 =item Final $ should be \$ or $name
2017 (F) You must now decide whether the final $ in a string was meant to be
2018 a literal dollar sign, or was meant to introduce a variable name that
2019 happens to be missing. So you have to put either the backslash or the
2022 =item flock() on closed filehandle %s
2024 (W closed) The filehandle you're attempting to flock() got itself closed
2025 some time before now. Check your control flow. flock() operates on
2026 filehandles. Are you attempting to call flock() on a dirhandle by the
2029 =item Format not terminated
2031 (F) A format must be terminated by a line with a solitary dot. Perl got
2032 to the end of your file without finding such a line.
2034 =item Format %s redefined
2036 (W redefine) You redefined a format. To suppress this warning, say
2039 no warnings 'redefine';
2040 eval "format NAME =...";
2043 =item Found = in conditional, should be ==
2053 (or something like that).
2055 =item %s found where operator expected
2057 (S syntax) The Perl lexer knows whether to expect a term or an operator.
2058 If it sees what it knows to be a term when it was expecting to see an
2059 operator, it gives you this warning. Usually it indicates that an
2060 operator or delimiter was omitted, such as a semicolon.
2062 =item gdbm store returned %d, errno %d, key "%s"
2064 (S) A warning from the GDBM_File extension that a store failed.
2066 =item gethostent not implemented
2068 (F) Your C library apparently doesn't implement gethostent(), probably
2069 because if it did, it'd feel morally obligated to return every hostname
2072 =item get%sname() on closed socket %s
2074 (W closed) You tried to get a socket or peer socket name on a closed
2075 socket. Did you forget to check the return value of your socket() call?
2077 =item getpwnam returned invalid UIC %#o for user "%s"
2079 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2080 C<getpwnam> operator returned an invalid UIC.
2082 =item getsockopt() on closed socket %s
2084 (W closed) You tried to get a socket option on a closed socket. Did you
2085 forget to check the return value of your socket() call? See
2086 L<perlfunc/getsockopt>.
2088 =item given is experimental
2090 (S experimental::smartmatch) C<given> depends on smartmatch, which
2091 is experimental, so its behavior may change or even be removed
2092 in any future release of perl. See the explanation under
2093 L<perlsyn/Experimental Details on given and when>.
2095 =item Global symbol "%s" requires explicit package name
2097 (F) You've said "use strict" or "use strict vars", which indicates
2098 that all variables must either be lexically scoped (using "my" or "state"),
2099 declared beforehand using "our", or explicitly qualified to say
2100 which package the global variable is in (using "::").
2102 =item glob failed (%s)
2104 (S glob) Something went wrong with the external program(s) used
2105 for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2106 pattern that caused the external program to fail and exit with a
2107 nonzero status. If the message indicates that the abnormal exit
2108 resulted in a coredump, this may also mean that your csh (C shell)
2109 is broken. If so, you should change all of the csh-related variables
2110 in config.sh: If you have tcsh, make the variables refer to it as
2111 if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2112 all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
2113 think csh is missing. In either case, after editing config.sh, run
2114 C<./Configure -S> and rebuild Perl.
2116 =item Glob not terminated
2118 (F) The lexer saw a left angle bracket in a place where it was expecting
2119 a term, so it's looking for the corresponding right angle bracket, and
2120 not finding it. Chances are you left some needed parentheses out
2121 earlier in the line, and you really meant a "less than".
2123 =item gmtime(%f) too large
2125 (W overflow) You called C<gmtime> with a number that was larger than
2126 it can reliably handle and C<gmtime> probably returned the wrong
2127 date. This warning is also triggered with NaN (the special
2128 not-a-number value).
2130 =item gmtime(%f) too small
2132 (W overflow) You called C<gmtime> with a number that was smaller than
2133 it can reliably handle and C<gmtime> probably returned the wrong date.
2135 =item Got an error from DosAllocMem
2137 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2138 version of Perl, and this should not happen anyway.
2140 =item goto must have label
2142 (F) Unlike with "next" or "last", you're not allowed to goto an
2143 unspecified destination. See L<perlfunc/goto>.
2145 =item Goto undefined subroutine%s
2147 (F) You tried to call a subroutine with C<goto &sub> syntax, but
2148 the indicated subroutine hasn't been defined, or if it was, it
2149 has since been undefined.
2151 =item Group name must start with a non-digit word character in regex; marked by
2152 S<<-- HERE> in m/%s/
2154 (F) Group names must follow the rules for perl identifiers, meaning
2155 they must start with a non-digit word character. A common cause of
2156 this error is using (?&0) instead of (?0). See L<perlre>.
2158 =item ()-group starts with a count
2160 (F) A ()-group started with a count. A count is supposed to follow
2161 something: a template character or a ()-group. See L<perlfunc/pack>.
2163 =item %s had compilation errors.
2165 (F) The final summary message when a C<perl -c> fails.
2167 =item Had to create %s unexpectedly
2169 (S internal) A routine asked for a symbol from a symbol table that ought
2170 to have existed already, but for some reason it didn't, and had to be
2171 created on an emergency basis to prevent a core dump.
2173 =item Hash %%s missing the % in argument %d of %s()
2175 (D deprecated) Really old Perl let you omit the % on hash names in some
2176 spots. This is now heavily deprecated.
2178 =item %s has too many errors
2180 (F) The parser has given up trying to parse the program after 10 errors.
2181 Further error messages would likely be uninformative.
2183 =item Hexadecimal number > 0xffffffff non-portable
2185 (W portable) The hexadecimal number you specified is larger than 2**32-1
2186 (4294967295) and therefore non-portable between systems. See
2187 L<perlport> for more on portability concerns.
2189 =item Identifier too long
2191 (F) Perl limits identifiers (names for variables, functions, etc.) to
2192 about 250 characters for simple names, and somewhat more for compound
2193 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2194 of Perl are likely to eliminate these arbitrary limitations.
2196 =item Ignoring zero length \N{} in character class in regex; marked by
2197 S<<-- HERE> in m/%s/
2199 (W regexp) Named Unicode character escapes C<(\N{...})> may return a
2200 zero-length sequence. When such an escape is used in a character class
2201 its behaviour is not well defined. Check that the correct escape has
2202 been used, and the correct charname handler is in scope.
2204 =item Illegal binary digit %s
2206 (F) You used a digit other than 0 or 1 in a binary number.
2208 =item Illegal binary digit %s ignored
2210 (W digit) You may have tried to use a digit other than 0 or 1 in a
2211 binary number. Interpretation of the binary number stopped before the
2214 =item Illegal character after '_' in prototype for %s : %s
2216 (W illegalproto) An illegal character was found in a prototype
2217 declaration. The '_' in a prototype must be followed by a ';',
2218 indicating the rest of the parameters are optional, or one of '@'
2219 or '%', since those two will accept 0 or more final parameters.
2221 =item Illegal character \%o (carriage return)
2223 (F) Perl normally treats carriage returns in the program text as it
2224 would any other whitespace, which means you should never see this error
2225 when Perl was built using standard options. For some reason, your
2226 version of Perl appears to have been built without this support. Talk
2227 to your Perl administrator.
2229 =item Illegal character in prototype for %s : %s
2231 (W illegalproto) An illegal character was found in a prototype declaration.
2232 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2234 =item Illegal declaration of anonymous subroutine
2236 (F) When using the C<sub> keyword to construct an anonymous subroutine,
2237 you must always specify a block of code. See L<perlsub>.
2239 =item Illegal declaration of subroutine %s
2241 (F) A subroutine was not declared correctly. See L<perlsub>.
2243 =item Illegal division by zero
2245 (F) You tried to divide a number by 0. Either something was wrong in
2246 your logic, or you need to put a conditional in to guard against
2249 =item Illegal hexadecimal digit %s ignored
2251 (W digit) You may have tried to use a character other than 0 - 9 or
2252 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2253 number stopped before the illegal character.
2255 =item Illegal modulus zero
2257 (F) You tried to divide a number by 0 to get the remainder. Most
2258 numbers don't take to this kindly.
2260 =item Illegal number of bits in vec
2262 (F) The number of bits in vec() (the third argument) must be a power of
2263 two from 1 to 32 (or 64, if your platform supports that).
2265 =item Illegal octal digit %s
2267 (F) You used an 8 or 9 in an octal number.
2269 =item Illegal octal digit %s ignored
2271 (W digit) You may have tried to use an 8 or 9 in an octal number.
2272 Interpretation of the octal number stopped before the 8 or 9.
2274 =item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
2276 (F) You wrote something like
2280 The C<"+"> is valid only when followed by digits, indicating a
2281 capturing group. See
2282 L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2284 =item Illegal switch in PERL5OPT: -%c
2286 (X) The PERL5OPT environment variable may only be used to set the
2287 following switches: B<-[CDIMUdmtw]>.
2289 =item Ill-formed CRTL environ value "%s"
2291 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
2292 internal environ array, and encountered an element without the C<=>
2293 delimiter used to separate keys from values. The element is ignored.
2295 =item Ill-formed message in prime_env_iter: |%s|
2297 (W internal) A warning peculiar to VMS. Perl tried to read a logical
2298 name or CLI symbol definition when preparing to iterate over %ENV, and
2299 didn't see the expected delimiter between key and value, so the line was
2302 =item (in cleanup) %s
2304 (W misc) This prefix usually indicates that a DESTROY() method raised
2305 the indicated exception. Since destructors are usually called by the
2306 system at arbitrary points during execution, and often a vast number of
2307 times, the warning is issued only once for any number of failures that
2308 would otherwise result in the same message being repeated.
2310 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2311 also result in this warning. See L<perlcall/G_KEEPERR>.
2313 =item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2316 (F) There was a syntax error within the C<(?[ ])>. This can happen if the
2317 expression inside the construct was completely empty, or if there are
2318 too many or few operands for the number of operators. Perl is not smart
2319 enough to give you a more precise indication as to what is wrong.
2321 =item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2324 (F) The method resolution order (MRO) of the given class is not
2325 C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2326 documentation in L<mro> for more information.
2328 =item In EBCDIC the v-string components cannot exceed 2147483647
2330 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2331 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2332 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2334 =item Infinite recursion in regex
2336 (F) You used a pattern that references itself without consuming any input
2337 text. You should check the pattern to ensure that recursive patterns
2338 either consume text or fail.
2340 =item Initialization of state variables in list context currently forbidden
2342 (F) Currently the implementation of "state" only permits the
2343 initialization of scalar variables in scalar context. Re-write
2344 C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2345 context. Constructions such as C<state (@a) = foo()> will be
2346 supported in a future perl release.
2348 =item %%s[%s] in scalar context better written as $%s[%s]
2350 (W syntax) In scalar context, you've used an array index/value slice
2351 (indicated by %) to select a single element of an array. Generally
2352 it's better to ask for a scalar value (indicated by $). The difference
2353 is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2354 returns and when evaluating its argument, while C<%foo[&bar]> provides
2355 a list context to its subscript, which can do weird things if you're
2356 expecting only one subscript. When called in list context, it also
2357 returns the index (what C<&bar> returns) in addition to the value.
2359 =item %%s{%s} in scalar context better written as $%s{%s}
2361 (W syntax) In scalar context, you've used a hash key/value slice
2362 (indicated by %) to select a single element of a hash. Generally it's
2363 better to ask for a scalar value (indicated by $). The difference
2364 is that C<$foo{&bar}> always behaves like a scalar, both in the value
2365 it returns and when evaluating its argument, while C<@foo{&bar}> and
2366 provides a list context to its subscript, which can do weird things
2367 if you're expecting only one subscript. When called in list context,
2368 it also returns the key in addition to the value.
2370 =item Insecure dependency in %s
2372 (F) You tried to do something that the tainting mechanism didn't like.
2373 The tainting mechanism is turned on when you're running setuid or
2374 setgid, or when you specify B<-T> to turn it on explicitly. The
2375 tainting mechanism labels all data that's derived directly or indirectly
2376 from the user, who is considered to be unworthy of your trust. If any
2377 such data is used in a "dangerous" operation, you get this error. See
2378 L<perlsec> for more information.
2380 =item Insecure directory in %s
2382 (F) You can't use system(), exec(), or a piped open in a setuid or
2383 setgid script if C<$ENV{PATH}> contains a directory that is writable by
2384 the world. Also, the PATH must not contain any relative directory.
2387 =item Insecure $ENV{%s} while running %s
2389 (F) You can't use system(), exec(), or a piped open in a setuid or
2390 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
2391 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2392 supplied (or potentially supplied) by the user. The script must set
2393 the path to a known value, using trustworthy data. See L<perlsec>.
2395 =item Insecure user-defined property %s
2397 (F) Perl detected tainted data when trying to compile a regular
2398 expression that contains a call to a user-defined character property
2399 function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2400 See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2402 =item In '(?...)', splitting the initial '(?' is deprecated in regex;
2403 marked by S<<-- HERE> in m/%s/
2405 (D regexp, deprecated) The two-character sequence C<"(?"> in
2406 this context in a regular expression pattern should be an
2407 indivisible token, with nothing intervening between the C<"(">
2408 and the C<"?">, but you separated them. Due to an accident of
2409 implementation, this prohibition was not enforced, but we do
2410 plan to forbid it in a future Perl version. This message
2411 serves as giving you fair warning of this pending change.
2413 =item Integer overflow in format string for %s
2415 (F) The indexes and widths specified in the format string of C<printf()>
2416 or C<sprintf()> are too large. The numbers must not overflow the size of
2417 integers for your architecture.
2419 =item Integer overflow in %s number
2421 (S overflow) The hexadecimal, octal or binary number you have specified
2422 either as a literal or as an argument to hex() or oct() is too big for
2423 your architecture, and has been converted to a floating point number.
2424 On a 32-bit architecture the largest hexadecimal, octal or binary number
2425 representable without overflow is 0xFFFFFFFF, 037777777777, or
2426 0b11111111111111111111111111111111 respectively. Note that Perl
2427 transparently promotes all numbers to a floating point representation
2428 internally--subject to loss of precision errors in subsequent
2431 =item Integer overflow in srand
2433 (S overflow) The number you have passed to srand is too big to fit
2434 in your architecture's integer representation. The number has been
2435 replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2436 architectures). This means you may be getting less randomness than
2437 you expect, because different random seeds above the maximum will
2438 return the same sequence of random numbers.
2440 =item Integer overflow in version
2442 =item Integer overflow in version %d
2444 (W overflow) Some portion of a version initialization is too large for
2445 the size of integers for your architecture. This is not a warning
2446 because there is no rational reason for a version to try and use an
2447 element larger than typically 2**32. This is usually caused by trying
2448 to use some odd mathematical operation as a version, like 100/9.
2450 =item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
2452 (P) Something went badly wrong in the regular expression parser.
2453 The S<<-- HERE> shows whereabouts in the regular expression the problem was
2456 =item Internal inconsistency in tracking vforks
2458 (S) A warning peculiar to VMS. Perl keeps track of the number of times
2459 you've called C<fork> and C<exec>, to determine whether the current call
2460 to C<exec> should affect the current script or a subprocess (see
2461 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2462 Perl is making a guess and treating this C<exec> as a request to
2463 terminate the Perl script and execute the specified command.
2465 =item internal %<num>p might conflict with future printf extensions
2467 (S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2468 formatting follows a slightly different set of rules when called from
2469 C or XS code. Specifically, formats consisting of digits followed
2470 by "p" (e.g., "%7p") are reserved for future use. If you see this
2471 message, then an XS module tried to call that routine with one such
2474 =item Internal urp in regex; marked by S<<-- HERE> in m/%s/
2476 (P) Something went badly awry in the regular expression parser. The
2477 S<<-- HERE> shows whereabouts in the regular expression the problem was
2480 =item %s (...) interpreted as function
2482 (W syntax) You've run afoul of the rule that says that any list operator
2483 followed by parentheses turns into a function, with all the list
2484 operators arguments found inside the parentheses. See
2485 L<perlop/Terms and List Operators (Leftward)>.
2487 =item Invalid %s attribute: %s
2489 (F) The indicated attribute for a subroutine or variable was not recognized
2490 by Perl or by a user-supplied handler. See L<attributes>.
2492 =item Invalid %s attributes: %s
2494 (F) The indicated attributes for a subroutine or variable were not
2495 recognized by Perl or by a user-supplied handler. See L<attributes>.
2497 =item Invalid character in charnames alias definition; marked by
2500 (F) You tried to create a custom alias for a character name, with
2501 the C<:alias> option to C<use charnames> and the specified character in
2502 the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2504 =item Invalid \0 character in %s for %s: %s\0%s
2506 (W syscalls) Embedded \0 characters in pathnames or other system call
2507 arguments produce a warning as of 5.20. The parts after the \0 were
2508 formerly ignored by system calls.
2510 =item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
2512 (F) Only certain characters are valid for character names. The
2513 indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2515 =item Invalid conversion in %s: "%s"
2517 (W printf) Perl does not understand the given format conversion. See
2518 L<perlfunc/sprintf>.
2520 =item Invalid escape in the specified encoding in regex; marked by
2521 S<<-- HERE> in m/%s/
2523 (W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
2524 didn't correspond to a single character through the conversion
2525 from the encoding specified by the encoding pragma.
2526 The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2527 instead, except within S<C<(?[ ])>>, where it is a fatal error.
2528 The S<<-- HERE> shows whereabouts in the regular expression the
2529 escape was discovered.
2531 =item Invalid hexadecimal number in \N{U+...}
2533 =item Invalid hexadecimal number in \N{U+...} in regex; marked by
2534 S<<-- HERE> in m/%s/
2536 (F) The character constant represented by C<...> is not a valid hexadecimal
2537 number. Either it is empty, or you tried to use a character other than
2538 0 - 9 or A - F, a - f in a hexadecimal number.
2540 =item Invalid module name %s with -%c option: contains single ':'
2542 (F) The module argument to perl's B<-m> and B<-M> command-line options
2543 cannot contain single colons in the module name, but only in the
2544 arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2545 B<-MFoo:Bar=baz> is not.
2547 =item Invalid mro name: '%s'
2549 (F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2550 where C<foo> is not a valid method resolution order (MRO). Currently,
2551 the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2552 a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2554 =item Invalid negative number (%s) in chr
2556 (W utf8) You passed a negative number to C<chr>. Negative numbers are
2557 not valid characters numbers, so it return the Unicode replacement
2560 =item invalid option -D%c, use -D'' to see choices
2562 (S debugging) Perl was called with invalid debugger flags. Call perl
2563 with the B<-D> option with no flags to see the list of acceptable values.
2564 See also L<perlrun/-Dletters>.
2566 =item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
2568 (F) The range specified in a character class had a minimum character
2569 greater than the maximum character. One possibility is that you forgot the
2570 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
2571 up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
2572 problem was discovered. See L<perlre>.
2574 =item Invalid range "%s" in transliteration operator
2576 (F) The range specified in the tr/// or y/// operator had a minimum
2577 character greater than the maximum character. See L<perlop>.
2579 =item Invalid separator character %s in attribute list
2581 (F) Something other than a colon or whitespace was seen between the
2582 elements of an attribute list. If the previous attribute had a
2583 parenthesised parameter list, perhaps that list was terminated too soon.
2586 =item Invalid separator character %s in PerlIO layer specification %s
2588 (W layer) When pushing layers onto the Perl I/O system, something other
2589 than a colon or whitespace was seen between the elements of a layer list.
2590 If the previous attribute had a parenthesised parameter list, perhaps that
2591 list was terminated too soon.
2593 =item Invalid strict version format (%s)
2595 (F) A version number did not meet the "strict" criteria for versions.
2596 A "strict" version number is a positive decimal number (integer or
2597 decimal-fraction) without exponentiation or else a dotted-decimal
2598 v-string with a leading 'v' character and at least three components.
2599 The parenthesized text indicates which criteria were not met.
2600 See the L<version> module for more details on allowed version formats.
2602 =item Invalid type '%s' in %s
2604 (F) The given character is not a valid pack or unpack type.
2605 See L<perlfunc/pack>.
2607 (W) The given character is not a valid pack or unpack type but used to be
2610 =item Invalid version format (%s)
2612 (F) A version number did not meet the "lax" criteria for versions.
2613 A "lax" version number is a positive decimal number (integer or
2614 decimal-fraction) without exponentiation or else a dotted-decimal
2615 v-string. If the v-string has fewer than three components, it
2616 must have a leading 'v' character. Otherwise, the leading 'v' is
2617 optional. Both decimal and dotted-decimal versions may have a
2618 trailing "alpha" component separated by an underscore character
2619 after a fractional or dotted-decimal component. The parenthesized
2620 text indicates which criteria were not met. See the L<version> module
2621 for more details on allowed version formats.
2623 =item Invalid version object
2625 (F) The internal structure of the version object was invalid.
2626 Perhaps the internals were modified directly in some way or
2627 an arbitrary reference was blessed into the "version" class.
2629 =item In '(*VERB...)', splitting the initial '(*' is deprecated in regex;
2630 marked by S<<-- HERE> in m/%s/
2632 (D regexp, deprecated) The two-character sequence C<"(*"> in
2633 this context in a regular expression pattern should be an
2634 indivisible token, with nothing intervening between the C<"(">
2635 and the C<"*">, but you separated them. Due to an accident of
2636 implementation, this prohibition was not enforced, but we do
2637 plan to forbid it in a future Perl version. This message
2638 serves as giving you fair warning of this pending change.
2640 =item ioctl is not implemented
2642 (F) Your machine apparently doesn't implement ioctl(), which is pretty
2643 strange for a machine that supports C.
2645 =item ioctl() on unopened %s
2647 (W unopened) You tried ioctl() on a filehandle that was never opened.
2648 Check your control flow and number of arguments.
2650 =item IO layers (like '%s') unavailable
2652 (F) Your Perl has not been configured to have PerlIO, and therefore
2653 you cannot use IO layers. To have PerlIO, Perl must be configured
2656 =item IO::Socket::atmark not implemented on this architecture
2658 (F) Your machine doesn't implement the sockatmark() functionality,
2659 neither as a system call nor an ioctl call (SIOCATMARK).
2661 =item $* is no longer supported
2663 (D deprecated, syntax) The special variable C<$*>, deprecated in older
2664 perls, has been removed as of 5.9.0 and is no longer supported. In
2665 previous versions of perl the use of C<$*> enabled or disabled multi-line
2666 matching within a string.
2668 Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
2669 modifiers. You can enable C</m> for a lexical scope (even a whole file)
2670 with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
2671 then all regular expressions behaved as if they were written using C</m>.)
2673 =item $# is no longer supported
2675 (D deprecated, syntax) The special variable C<$#>, deprecated in older
2676 perls, has been removed as of 5.9.3 and is no longer supported. You
2677 should use the printf/sprintf functions instead.
2679 =item '%s' is not a code reference
2681 (W overload) The second (fourth, sixth, ...) argument of
2682 overload::constant needs to be a code reference. Either
2683 an anonymous subroutine, or a reference to a subroutine.
2685 =item '%s' is not an overloadable type
2687 (W overload) You tried to overload a constant type the overload package is
2690 =item -i used with no filenames on the command line, reading from STDIN
2692 (S inplace) The C<-i> option was passed on the command line, indicating
2693 that the script is intended to edit files in place, but no files were
2694 given. This is usually a mistake, since editing STDIN in place doesn't
2695 make sense, and can be confusing because it can make perl look like
2696 it is hanging when it is really just trying to read from STDIN. You
2697 should either pass a filename to edit, or remove C<-i> from the command
2698 line. See L<perlrun> for more details.
2700 =item Junk on end of regexp in regex m/%s/
2702 (P) The regular expression parser is confused.
2704 =item keys on reference is experimental
2706 (S experimental::autoderef) C<keys> with a scalar argument is experimental
2707 and may change or be removed in a future Perl version. If you want to
2708 take the risk of using this feature, simply disable this warning:
2710 no warnings "experimental::autoderef";
2712 =item Label not found for "last %s"
2714 (F) You named a loop to break out of, but you're not currently in a loop
2715 of that name, not even if you count where you were called from. See
2718 =item Label not found for "next %s"
2720 (F) You named a loop to continue, but you're not currently in a loop of
2721 that name, not even if you count where you were called from. See
2724 =item Label not found for "redo %s"
2726 (F) You named a loop to restart, but you're not currently in a loop of
2727 that name, not even if you count where you were called from. See
2730 =item leaving effective %s failed
2732 (F) While under the C<use filetest> pragma, switching the real and
2733 effective uids or gids failed.
2735 =item length/code after end of string in unpack
2737 (F) While unpacking, the string buffer was already used up when an unpack
2738 length/code combination tried to obtain more data. This results in
2739 an undefined value for the length. See L<perlfunc/pack>.
2741 =item length() used on %s (did you mean "scalar(%s)"?)
2743 (W syntax) You used length() on either an array or a hash when you
2744 probably wanted a count of the items.
2746 Array size can be obtained by doing:
2750 The number of items in a hash can be obtained by doing:
2754 =item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2756 (F) An extension is attempting to insert text into the current parse
2757 (using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2758 couldn't be part of the current input. This is an inherent pitfall
2759 of the stuffing mechanism, and one of the reasons to avoid it. Where
2760 it is necessary to stuff, stuffing only plain ASCII is recommended.
2762 =item Lexing code internal error (%s)
2764 (F) Lexing code supplied by an extension violated the lexer's API in a
2767 =item listen() on closed socket %s
2769 (W closed) You tried to do a listen on a closed socket. Did you forget
2770 to check the return value of your socket() call? See
2773 =item List form of piped open not implemented
2775 (F) On some platforms, notably Windows, the three-or-more-arguments
2776 form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2777 Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2779 =item localtime(%f) too large
2781 (W overflow) You called C<localtime> with a number that was larger
2782 than it can reliably handle and C<localtime> probably returned the
2783 wrong date. This warning is also triggered with NaN (the special
2784 not-a-number value).
2786 =item localtime(%f) too small
2788 (W overflow) You called C<localtime> with a number that was smaller
2789 than it can reliably handle and C<localtime> probably returned the
2792 =item Lookbehind longer than %d not implemented in regex m/%s/
2794 (F) There is currently a limit on the length of string which lookbehind can
2795 handle. This restriction may be eased in a future release.
2797 =item Lost precision when %s %f by 1
2799 (W imprecision) The value you attempted to increment or decrement by one
2800 is too large for the underlying floating point representation to store
2801 accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2802 warning because it has already switched from integers to floating point
2803 when values are too large for integers, and now even floating point is
2804 insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
2806 =item lstat() on filehandle%s
2808 (W io) You tried to do an lstat on a filehandle. What did you mean
2809 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2810 instead on the filehandle.)
2812 =item lvalue attribute %s already-defined subroutine
2814 (W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2815 attribute on or off on a Perl subroutine that is already defined
2816 does not always work properly. It may or may not do what you
2817 want, depending on what code is inside the subroutine, with exact
2818 details subject to change between Perl versions. Only do this
2819 if you really know what you are doing.
2821 =item lvalue attribute ignored after the subroutine has been defined
2823 (W misc) Using the C<:lvalue> declarative syntax to make a Perl
2824 subroutine an lvalue subroutine after it has been defined is
2825 not permitted. To make the subroutine an lvalue subroutine,
2826 add the lvalue attribute to the definition, or put the C<sub
2827 foo :lvalue;> declaration before the definition.
2829 See also L<attributes.pm|attributes>.
2831 =item Magical list constants are not supported
2833 (F) You assigned a magical array to a stash element, and then tried
2834 to use the subroutine from the same slot. You are asking Perl to do
2835 something it cannot do, details subject to change between Perl versions.
2837 =item Malformed integer in [] in pack
2839 (F) Between the brackets enclosing a numeric repeat count only digits
2840 are permitted. See L<perlfunc/pack>.
2842 =item Malformed integer in [] in unpack
2844 (F) Between the brackets enclosing a numeric repeat count only digits
2845 are permitted. See L<perlfunc/pack>.
2847 =item Malformed PERLLIB_PREFIX
2849 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2856 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2857 a builtin library search path, prefix2 is substituted. The error may
2858 appear if components are not found, or are too long. See
2859 "PERLLIB_PREFIX" in L<perlos2>.
2861 =item Malformed prototype for %s: %s
2863 (F) You tried to use a function with a malformed prototype. The
2864 syntax of function prototypes is given a brief compile-time check for
2865 obvious errors like invalid characters. A more rigorous check is run
2866 when the function is called.
2868 =item Malformed UTF-8 character (%s)
2870 (S utf8)(F) Perl detected a string that didn't comply with UTF-8
2871 encoding rules, even though it had the UTF8 flag on.
2873 One possible cause is that you set the UTF8 flag yourself for data that
2874 you thought to be in UTF-8 but it wasn't (it was for example legacy
2875 8-bit data). To guard against this, you can use Encode::decode_utf8.
2877 If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2878 sequences are handled gracefully, but if you use C<:utf8>, the flag is
2879 set without validating the data, possibly resulting in this error
2882 See also L<Encode/"Handling Malformed Data">.
2884 =item Malformed UTF-8 character immediately after '%s'
2886 (F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2887 encoding rules. The message prints out the properly encoded characters
2888 just before the first bad one. If C<utf8> warnings are enabled, a
2889 warning is generated that gives more details about the type of
2892 =item Malformed UTF-8 returned by \N{%s} immediately after '%s'
2894 (F) The charnames handler returned malformed UTF-8.
2896 =item Malformed UTF-8 string in '%c' format in unpack
2898 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2899 rules and perl was unable to guess how to make more progress.
2901 =item Malformed UTF-8 string in pack
2903 (F) You tried to pack something that didn't comply with UTF-8 encoding
2904 rules and perl was unable to guess how to make more progress.
2906 =item Malformed UTF-8 string in unpack
2908 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2909 rules and perl was unable to guess how to make more progress.
2911 =item Malformed UTF-16 surrogate
2913 (F) Perl thought it was reading UTF-16 encoded character data but while
2914 doing it Perl met a malformed Unicode surrogate.
2916 =item Matched non-Unicode code point 0x%X against Unicode property; may
2919 (S non_unicode) Perl allows strings to contain a superset of
2920 Unicode code points; each code point may be as large as what is storable
2921 in an unsigned integer on your system, but these may not be accepted by
2922 other languages/systems. This message occurs when you matched a string
2923 containing such a code point against a regular expression pattern, and
2924 the code point was matched against a Unicode property, C<\p{...}> or
2925 C<\P{...}>. Unicode properties are only defined on Unicode code points,
2926 so the result of this match is undefined by Unicode, but Perl (starting
2927 in v5.20) treats non-Unicode code points as if they were typical
2928 unassigned Unicode ones, and matched this one accordingly. Whether a
2929 given property matches these code points or not is specified in
2930 L<perluniprops/Properties accessible through \p{} and \P{}>.
2932 This message is suppressed (unless it has been made fatal) if it is
2933 immaterial to the results of the match if the code point is Unicode or
2934 not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2935 the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2936 Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2937 every code point except these 22.)
2939 Getting this message indicates that the outcome of the match arguably
2940 should have been the opposite of what actually happened. If you think
2941 that is the case, you may wish to make the C<non_unicode> warnings
2942 category fatal; if you agree with Perl's decision, you may wish to turn
2945 See L<perlunicode/Beyond Unicode code points> for more information.
2947 =item %s matches null string many times in regex; marked by S<<-- HERE> in
2950 (W regexp) The pattern you've specified would be an infinite loop if the
2951 regular expression engine didn't specifically check for that. The S<<-- HERE>
2952 shows whereabouts in the regular expression the problem was discovered.
2955 =item Maximal count of pending signals (%u) exceeded
2957 (F) Perl aborted due to too high a number of signals pending. This
2958 usually indicates that your operating system tried to deliver signals
2959 too fast (with a very high priority), starving the perl process from
2960 resources it would need to reach a point where it can process signals
2961 safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2963 =item "%s" may clash with future reserved word
2965 (W) This warning may be due to running a perl5 script through a perl4
2966 interpreter, especially if the word that is being warned about is
2969 =item '%' may not be used in pack
2971 (F) You can't pack a string by supplying a checksum, because the
2972 checksumming process loses information, and you can't go the other way.
2973 See L<perlfunc/unpack>.
2975 =item Method for operation %s not found in package %s during blessing
2977 (F) An attempt was made to specify an entry in an overloading table that
2978 doesn't resolve to a valid subroutine. See L<overload>.
2980 =item Method %s not permitted
2984 =item Might be a runaway multi-line %s string starting on line %d
2986 (S) An advisory indicating that the previous error may have been caused
2987 by a missing delimiter on a string or pattern, because it eventually
2988 ended earlier on the current line.
2990 =item Misplaced _ in number
2992 (W syntax) An underscore (underbar) in a numeric constant did not
2993 separate two digits.
2995 =item Missing argument in %s
2997 (W uninitialized) A printf-type format required more arguments than were
3000 =item Missing argument to -%c
3002 (F) The argument to the indicated command line switch must follow
3003 immediately after the switch, without intervening spaces.
3005 =item Missing braces on \N{}
3007 =item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
3009 (F) Wrong syntax of character name literal C<\N{charname}> within
3010 double-quotish context. This can also happen when there is a space
3011 (or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3012 This modifier does not change the requirement that the brace immediately
3015 =item Missing braces on \o{}
3017 (F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3019 =item Missing comma after first argument to %s function
3021 (F) While certain functions allow you to specify a filehandle or an
3022 "indirect object" before the argument list, this ain't one of them.
3024 =item Missing command in piped open
3026 (W pipe) You used the C<open(FH, "| command")> or
3027 C<open(FH, "command |")> construction, but the command was missing or
3030 =item Missing control char name in \c
3032 (F) A double-quoted string ended with "\c", without the required control
3035 =item Missing ']' in prototype for %s : %s
3037 (W illegalproto) A grouping was started with C<[> but never closed with C<]>.
3039 =item Missing name in "%s sub"
3041 (F) The syntax for lexically scoped subroutines requires that
3042 they have a name with which they can be found.
3044 =item Missing $ on loop variable
3046 (F) Apparently you've been programming in B<csh> too much. Variables
3047 are always mentioned with the $ in Perl, unlike in the shells, where it
3048 can vary from one line to the next.
3050 =item (Missing operator before %s?)
3052 (S syntax) This is an educated guess made in conjunction with the message
3053 "%s found where operator expected". Often the missing operator is a comma.
3055 =item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
3057 (F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3059 =item Missing right brace on \N{} or unescaped left brace after \N
3061 (F) C<\N> has two meanings.
3063 The traditional one has it followed by a name enclosed in braces,
3064 meaning the character (or sequence of characters) given by that
3065 name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
3066 double-quoted strings and regular expression patterns. In patterns,
3067 it doesn't have the meaning an unescaped C<*> does.
3069 Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3070 in patterns, namely to match a non-newline character. (This is short
3071 for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3073 This can lead to some ambiguities. When C<\N> is not followed immediately
3074 by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3075 form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3076 means to match the given quantity of non-newlines (in these examples,
3077 3; and 5 or more, respectively). In all other case, where there is a
3078 C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3080 However, if there is no matching C<}>, Perl doesn't know if it was
3081 mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3082 If you meant the former, add the right brace; if you meant the latter,
3083 escape the brace with a backslash, like so: C<\N\{>
3085 =item Missing right curly or square bracket
3087 (F) The lexer counted more opening curly or square brackets than closing
3088 ones. As a general rule, you'll find it's missing near the place you
3091 =item (Missing semicolon on previous line?)
3093 (S syntax) This is an educated guess made in conjunction with the message
3094 "%s found where operator expected". Don't automatically put a semicolon on
3095 the previous line just because you saw this message.
3097 =item Modification of a read-only value attempted
3099 (F) You tried, directly or indirectly, to change the value of a
3100 constant. You didn't, of course, try "2 = 1", because the compiler
3101 catches that. But an easy way to do the same thing is:
3103 sub mod { $_[0] = 1 }
3106 Another way is to assign to a substr() that's off the end of the string.
3108 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3109 is aliased to a constant in the look I<LIST>:
3112 foreach my $n ($x, 2) {
3113 $n *= 2; # modifies the $x, but fails on attempt to
3116 =item Modification of non-creatable array value attempted, %s
3118 (F) You tried to make an array value spring into existence, and the
3119 subscript was probably negative, even counting from end of the array
3122 =item Modification of non-creatable hash value attempted, %s
3124 (P) You tried to make a hash value spring into existence, and it
3125 couldn't be created for some peculiar reason.
3127 =item Module name must be constant
3129 (F) Only a bare module name is allowed as the first argument to a "use".
3131 =item Module name required with -%c option
3133 (F) The C<-M> or C<-m> options say that Perl should load some module, but
3134 you omitted the name of the module. Consult L<perlrun> for full details
3135 about C<-M> and C<-m>.
3137 =item More than one argument to '%s' open
3139 (F) The C<open> function has been asked to open multiple files. This
3140 can happen if you are trying to open a pipe to a command that takes a
3141 list of arguments, but have forgotten to specify a piped open mode.
3142 See L<perlfunc/open> for details.
3144 =item mprotect for COW string %p %u failed with %d
3146 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3147 L<perlguts/"Copy on Write">), but a shared string buffer
3148 could not be made read-only.
3150 =item mprotect for %p %u failed with %d
3152 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3153 but an op tree could not be made read-only.
3155 =item mprotect RW for COW string %p %u failed with %d
3157 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3158 L<perlguts/"Copy on Write">), but a read-only shared string
3159 buffer could not be made mutable.
3161 =item mprotect RW for %p %u failed with %d
3163 (S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
3164 L<perlhacktips>), but a read-only op tree could not be made
3165 mutable before freeing the ops.
3167 =item msg%s not implemented
3169 (F) You don't have System V message IPC on your system.
3171 =item Multidimensional syntax %s not supported
3173 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3174 They're written like C<$foo[1][2][3]>, as in C.
3176 =item '/' must follow a numeric type in unpack
3178 (F) You had an unpack template that contained a '/', but this did not
3179 follow some unpack specification producing a numeric value.
3180 See L<perlfunc/pack>.
3182 =item "my sub" not yet implemented
3184 (F) Lexically scoped subroutines are not yet implemented. Don't try
3187 =item "my %s" used in sort comparison
3189 (W syntax) The package variables $a and $b are used for sort comparisons.
3190 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3191 sort comparison block, and the variable had earlier been declared as a
3192 lexical variable. Either qualify the sort variable with the package
3193 name, or rename the lexical variable.
3195 =item "my" variable %s can't be in a package
3197 (F) Lexically scoped variables aren't in a package, so it doesn't make
3198 sense to try to declare one with a package qualifier on the front. Use
3199 local() if you want to localize a package variable.
3201 =item Name "%s::%s" used only once: possible typo
3203 (W once) Typographical errors often show up as unique variable
3204 names. If you had a good reason for having a unique name, then
3205 just mention it again somehow to suppress the message. The C<our>
3206 declaration is provided for this purpose.
3208 NOTE: This warning detects symbols that have been used only once
3209 so $c, @c, %c, *c, &c, sub c{}, c(), and c (the filehandle or
3210 format) are considered the same; if a program uses $c only once
3211 but also uses any of the others it will not trigger this warning.
3212 Symbols beginning with an underscore and symbols using special
3213 identifiers (q.v. L<perldata>) are exempt from this warning.
3215 =item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
3217 (F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3218 exactly 3 digits long. This helps catch some ambiguities. If your
3219 constant is too short, add leading zeros, like
3221 (?[ [ \078 ] ]) # Syntax error!
3222 (?[ [ \0078 ] ]) # Works
3223 (?[ [ \007 8 ] ]) # Clearer
3225 The maximum number this construct can express is C<\777>. If you
3226 need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3227 two separate things, you need to separate them:
3229 (?[ [ \7776 ] ]) # Syntax error!
3230 (?[ [ \o{7776} ] ]) # One meaning
3231 (?[ [ \777 6 ] ]) # Another meaning
3232 (?[ [ \777 \006 ] ]) # Still another
3234 =item Negative '/' count in unpack
3236 (F) The length count obtained from a length/code unpack operation was
3237 negative. See L<perlfunc/pack>.
3239 =item Negative length
3241 (F) You tried to do a read/write/send/recv operation with a buffer
3242 length that is less than 0. This is difficult to imagine.
3244 =item Negative offset to vec in lvalue context
3246 (F) When C<vec> is called in an lvalue context, the second argument must be
3247 greater than or equal to zero.
3249 =item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
3251 (F) You can't quantify a quantifier without intervening parentheses.
3252 So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
3253 whereabouts in the regular expression the problem was discovered.
3255 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
3256 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
3258 =item %s never introduced
3260 (S internal) The symbol in question was declared but somehow went out of
3261 scope before it could possibly have been used.
3263 =item next::method/next::can/maybe::next::method cannot find enclosing method
3265 (F) C<next::method> needs to be called within the context of a
3266 real method in a real package, and it could not find such a context.
3269 =item \N in a character class must be a named character: \N{...} in regex;
3270 marked by S<<-- HERE> in m/%s/
3272 (F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3273 bracketed character class, for the same reason that C<.> in a character
3274 class loses its specialness: it matches almost everything, which is
3275 probably not what you want.
3277 =item \N{} in character class restricted to one character in regex; marked
3278 by S<<-- HERE> in m/%s/
3280 (F) Named Unicode character escapes C<(\N{...})> may return a
3281 multi-character sequence. Such an escape may not be used in
3282 a character class, because character classes always match one
3283 character of input. Check that the correct escape has been used,
3284 and the correct charname handler is in scope. The S<<-- HERE> shows
3285 whereabouts in the regular expression the problem was discovered.
3287 =item \N{NAME} must be resolved by the lexer in regex; marked by
3288 S<<-- HERE> in m/%s/
3290 (F) When compiling a regex pattern, an unresolved named character or
3291 sequence was encountered. This can happen in any of several ways that
3292 bypass the lexer, such as using single-quotish context, or an extra
3293 backslash in double-quotish:
3295 $re = '\N{SPACE}'; # Wrong!
3296 $re = "\\N{SPACE}"; # Wrong!
3299 Instead, use double-quotes with a single backslash:
3301 $re = "\N{SPACE}"; # ok
3304 The lexer can be bypassed as well by creating the pattern from smaller
3308 /${re}{SPACE}/; # Wrong!
3310 It's not a good idea to split a construct in the middle like this, and
3311 it doesn't work here. Instead use the solution above.
3313 Finally, the message also can happen under the C</x> regex modifier when the
3314 C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
3316 /\N {SPACE}/x; # Wrong!
3319 =item No %s allowed while running setuid
3321 (F) Certain operations are deemed to be too insecure for a setuid or
3322 setgid script to even be allowed to attempt. Generally speaking there
3323 will be another way to do what you want that is, if not secure, at least
3324 securable. See L<perlsec>.
3326 =item No code specified for -%c
3328 (F) Perl's B<-e> and B<-E> command-line options require an argument. If
3329 you want to run an empty program, pass the empty string as a separate
3330 argument or run a program consisting of a single 0 or 1:
3336 =item No comma allowed after %s
3338 (F) A list operator that has a filehandle or "indirect object" is
3339 not allowed to have a comma between that and the following arguments.
3340 Otherwise it'd be just another one of the arguments.
3342 One possible cause for this is that you expected to have imported
3343 a constant to your name space with B<use> or B<import> while no such
3344 importing took place, it may for example be that your operating
3345 system does not support that particular constant. Hopefully you did
3346 use an explicit import list for the constants you expect to see;
3347 please see L<perlfunc/use> and L<perlfunc/import>. While an
3348 explicit import list would probably have caught this error earlier
3349 it naturally does not remedy the fact that your operating system
3350 still does not support that constant. Maybe you have a typo in
3351 the constants of the symbol import list of B<use> or B<import> or in the
3352 constant name at the line where this error was triggered?
3354 =item No command into which to pipe on command line
3356 (F) An error peculiar to VMS. Perl handles its own command line
3357 redirection, and found a '|' at the end of the command line, so it
3358 doesn't know where you want to pipe the output from this command.
3360 =item No DB::DB routine defined
3362 (F) The currently executing code was compiled with the B<-d> switch, but
3363 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3364 module) didn't define a routine to be called at the beginning of each
3367 =item No dbm on this machine
3369 (P) This is counted as an internal error, because every machine should
3370 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
3372 =item No DB::sub routine defined
3374 (F) The currently executing code was compiled with the B<-d> switch, but
3375 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3376 module) didn't define a C<DB::sub> routine to be called at the beginning
3377 of each ordinary subroutine call.
3379 =item No directory specified for -I
3381 (F) The B<-I> command-line switch requires a directory name as part of the
3382 I<same> argument. Use B<-Ilib>, for instance. B<-I lib> won't work.
3384 =item No error file after 2> or 2>> on command line
3386 (F) An error peculiar to VMS. Perl handles its own command line
3387 redirection, and found a '2>' or a '2>>' on the command line, but can't
3388 find the name of the file to which to write data destined for stderr.
3390 =item No group ending character '%c' found in template
3392 (F) A pack or unpack template has an opening '(' or '[' without its
3393 matching counterpart. See L<perlfunc/pack>.
3395 =item No input file after < on command line
3397 (F) An error peculiar to VMS. Perl handles its own command line
3398 redirection, and found a '<' on the command line, but can't find the
3399 name of the file from which to read data for stdin.
3401 =item No next::method '%s' found for %s
3403 (F) C<next::method> found no further instances of this method name
3404 in the remaining packages of the MRO of this class. If you don't want
3405 it throwing an exception, use C<maybe::next::method>
3406 or C<next::can>. See L<mro>.
3408 =item Non-hex character in regex; marked by S<<-- HERE> in m/%s/
3410 (F) In a regular expression, there was a non-hexadecimal character where
3411 a hex one was expected, like
3416 =item Non-octal character in regex; marked by S<<-- HERE> in m/%s/
3418 (F) In a regular expression, there was a non-octal character where
3419 an octal one was expected, like
3423 =item Non-octal character '%c'. Resolved as "%s"
3425 (W digit) In parsing an octal numeric constant, a character was
3426 unexpectedly encountered that isn't octal. The resulting value
3429 =item "no" not allowed in expression
3431 (F) The "no" keyword is recognized and executed at compile time, and
3432 returns no useful value. See L<perlmod>.
3434 =item Non-string passed as bitmask
3436 (W misc) A number has been passed as a bitmask argument to select().
3437 Use the vec() function to construct the file descriptor bitmasks for
3438 select. See L<perlfunc/select>.
3440 =item No output file after > on command line
3442 (F) An error peculiar to VMS. Perl handles its own command line
3443 redirection, and found a lone '>' at the end of the command line, so it
3444 doesn't know where you wanted to redirect stdout.
3446 =item No output file after > or >> on command line
3448 (F) An error peculiar to VMS. Perl handles its own command line
3449 redirection, and found a '>' or a '>>' on the command line, but can't
3450 find the name of the file to which to write data destined for stdout.
3452 =item No package name allowed for variable %s in "our"
3454 (F) Fully qualified variable names are not allowed in "our"
3455 declarations, because that doesn't make much sense under existing
3456 semantics. Such syntax is reserved for future extensions.
3458 =item No Perl script found in input
3460 (F) You called C<perl -x>, but no line was found in the file beginning
3461 with #! and containing the word "perl".
3463 =item No setregid available
3465 (F) Configure didn't find anything resembling the setregid() call for
3468 =item No setreuid available
3470 (F) Configure didn't find anything resembling the setreuid() call for
3473 =item No such class %s
3475 (F) You provided a class qualifier in a "my", "our" or "state"
3476 declaration, but this class doesn't exist at this point in your program.
3478 =item No such class field "%s" in variable %s of type %s
3480 (F) You tried to access a key from a hash through the indicated typed
3481 variable but that key is not allowed by the package of the same type.
3482 The indicated package has restricted the set of allowed keys using the
3485 =item No such hook: %s
3487 (F) You specified a signal hook that was not recognized by Perl.
3488 Currently, Perl accepts C<__DIE__> and C<__WARN__> as valid signal hooks.
3490 =item No such pipe open
3492 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
3493 close a pipe which hadn't been opened. This should have been caught
3494 earlier as an attempt to close an unopened filehandle.
3496 =item No such signal: SIG%s
3498 (W signal) You specified a signal name as a subscript to %SIG that was
3499 not recognized. Say C<kill -l> in your shell to see the valid signal
3500 names on your system.
3502 =item Not a CODE reference
3504 (F) Perl was trying to evaluate a reference to a code value (that is, a
3505 subroutine), but found a reference to something else instead. You can
3506 use the ref() function to find out what kind of ref it really was. See
3509 =item Not a GLOB reference
3511 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
3512 symbol table entry that looks like C<*foo>), but found a reference to
3513 something else instead. You can use the ref() function to find out what
3514 kind of ref it really was. See L<perlref>.
3516 =item Not a HASH reference
3518 (F) Perl was trying to evaluate a reference to a hash value, but found a
3519 reference to something else instead. You can use the ref() function to
3520 find out what kind of ref it really was. See L<perlref>.
3522 =item Not an ARRAY reference
3524 (F) Perl was trying to evaluate a reference to an array value, but found
3525 a reference to something else instead. You can use the ref() function
3526 to find out what kind of ref it really was. See L<perlref>.
3528 =item Not an unblessed ARRAY reference
3530 (F) You passed a reference to a blessed array to C<push>, C<shift> or
3531 another array function. These only accept unblessed array references
3532 or arrays beginning explicitly with C<@>.
3534 =item Not a SCALAR reference
3536 (F) Perl was trying to evaluate a reference to a scalar value, but found
3537 a reference to something else instead. You can use the ref() function
3538 to find out what kind of ref it really was. See L<perlref>.
3540 =item Not a subroutine reference
3542 (F) Perl was trying to evaluate a reference to a code value (that is, a
3543 subroutine), but found a reference to something else instead. You can
3544 use the ref() function to find out what kind of ref it really was. See
3547 =item Not a subroutine reference in overload table
3549 (F) An attempt was made to specify an entry in an overloading table that
3550 doesn't somehow point to a valid subroutine. See L<overload>.
3552 =item Not enough arguments for %s
3554 (F) The function requires more arguments than you specified.
3556 =item Not enough format arguments
3558 (W syntax) A format specified more picture fields than the next line
3559 supplied. See L<perlform>.
3563 (A) You've accidentally run your script through the Bourne shell instead
3564 of Perl. Check the #! line, or manually feed your script into Perl
3567 =item (?[...]) not valid in locale in regex; marked by S<<-- HERE> in m/%s/
3569 (F) C<(?[...])> cannot be used within the scope of a C<S<use locale>> or with
3570 an C</l> regular expression modifier, as that would require deferring
3571 to run-time the calculation of what it should evaluate to, and it is
3572 regex compile-time only.
3574 =item no UTC offset information; assuming local time is UTC
3576 (S) A warning peculiar to VMS. Perl was unable to find the local
3577 timezone offset, so it's assuming that local system time is equivalent
3578 to UTC. If it's not, define the logical name
3579 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
3580 need to be added to UTC to get local time.
3582 =item Null filename used
3584 (F) You can't require the null filename, especially because on many
3585 machines that means the current directory! See L<perlfunc/require>.
3587 =item NULL OP IN RUN
3589 (S debugging) Some internal routine called run() with a null opcode
3592 =item Null picture in formline
3594 (F) The first argument to formline must be a valid format picture
3595 specification. It was found to be empty, which probably means you
3596 supplied it an uninitialized value. See L<perlform>.
3600 (P) An attempt was made to realloc NULL.
3602 =item NULL regexp argument
3604 (P) The internal pattern matching routines blew it big time.
3606 =item NULL regexp parameter
3608 (P) The internal pattern matching routines are out of their gourd.
3610 =item Number too long
3612 (F) Perl limits the representation of decimal numbers in programs to
3613 about 250 characters. You've exceeded that length. Future
3614 versions of Perl are likely to eliminate this arbitrary limitation. In
3615 the meantime, try using scientific notation (e.g. "1e6" instead of
3618 =item Number with no digits
3620 (F) Perl was looking for a number but found nothing that looked like
3621 a number. This happens, for example with C<\o{}>, with no number between
3624 =item Octal number > 037777777777 non-portable
3626 (W portable) The octal number you specified is larger than 2**32-1
3627 (4294967295) and therefore non-portable between systems. See
3628 L<perlport> for more on portability concerns.
3630 =item Odd number of arguments for overload::constant
3632 (W overload) The call to overload::constant contained an odd number of
3633 arguments. The arguments should come in pairs.
3635 =item Odd number of elements in anonymous hash
3637 (W misc) You specified an odd number of elements to initialize a hash,
3638 which is odd, because hashes come in key/value pairs.
3640 =item Odd number of elements in hash assignment
3642 (W misc) You specified an odd number of elements to initialize a hash,
3643 which is odd, because hashes come in key/value pairs.
3645 =item Offset outside string
3647 (F)(W layer) You tried to do a read/write/send/recv/seek operation
3648 with an offset pointing outside the buffer. This is difficult to
3649 imagine. The sole exceptions to this are that zero padding will
3650 take place when going past the end of the string when either
3651 C<sysread()>ing a file, or when seeking past the end of a scalar opened
3652 for I/O (in anticipation of future reads and to imitate the behaviour
3655 =item %s() on unopened %s
3657 (W unopened) An I/O operation was attempted on a filehandle that was
3658 never initialized. You need to do an open(), a sysopen(), or a socket()
3659 call, or call a constructor from the FileHandle package.
3661 =item -%s on unopened filehandle %s
3663 (W unopened) You tried to invoke a file test operator on a filehandle
3664 that isn't open. Check your control flow. See also L<perlfunc/-X>.
3668 (S internal) An internal warning that the grammar is screwed up.
3672 (S internal) An internal warning that the grammar is screwed up.
3674 =item Opening dirhandle %s also as a file
3676 (D io, deprecated) You used open() to associate a filehandle to
3677 a symbol (glob or scalar) that already holds a dirhandle.
3678 Although legal, this idiom might render your code confusing
3681 =item Opening filehandle %s also as a directory
3683 (D io, deprecated) You used opendir() to associate a dirhandle to
3684 a symbol (glob or scalar) that already holds a filehandle.
3685 Although legal, this idiom might render your code confusing
3688 =item Operand with no preceding operator in regex; marked by S<<-- HERE> in
3691 (F) You wrote something like
3693 (?[ \p{Digit} \p{Thai} ])
3695 There are two operands, but no operator giving how you want to combine
3698 =item Operation "%s": no method found, %s
3700 (F) An attempt was made to perform an overloaded operation for which no
3701 handler was defined. While some handlers can be autogenerated in terms
3702 of other handlers, there is no default handler for any operation, unless
3703 the C<fallback> overloading key is specified to be true. See L<overload>.
3705 =item Operation "%s" returns its argument for non-Unicode code point 0x%X
3707 (S non_unicode) You performed an operation requiring Unicode semantics
3708 on a code point that is not in Unicode, so what it should do is not
3709 defined. Perl has chosen to have it do nothing, and warn you.
3711 If the operation shown is "ToFold", it means that case-insensitive
3712 matching in a regular expression was done on the code point.
3714 If you know what you are doing you can turn off this warning by
3715 C<no warnings 'non_unicode';>.
3717 =item Operation "%s" returns its argument for UTF-16 surrogate U+%X
3719 (S surrogate) You performed an operation requiring Unicode
3720 semantics on a Unicode surrogate. Unicode frowns upon the use
3721 of surrogates for anything but storing strings in UTF-16, but
3722 semantics are (reluctantly) defined for the surrogates, and
3723 they are to do nothing for this operation. Because the use of
3724 surrogates can be dangerous, Perl warns.
3726 If the operation shown is "ToFold", it means that case-insensitive
3727 matching in a regular expression was done on the code point.
3729 If you know what you are doing you can turn off this warning by
3730 C<no warnings 'surrogate';>.
3732 =item Operator or semicolon missing before %s
3734 (S ambiguous) You used a variable or subroutine call where the parser
3735 was expecting an operator. The parser has assumed you really meant to
3736 use an operator, but this is highly likely to be incorrect. For
3737 example, if you say "*foo *foo" it will be interpreted as if you said
3740 =item "our" variable %s redeclared
3742 (W misc) You seem to have already declared the same global once before
3743 in the current lexical scope.
3745 =item Out of memory!
3747 (X) The malloc() function returned 0, indicating there was insufficient
3748 remaining memory (or virtual memory) to satisfy the request. Perl has
3749 no option but to exit immediately.
3751 At least in Unix you may be able to get past this by increasing your
3752 process datasize limits: in csh/tcsh use C<limit> and
3753 C<limit datasize n> (where C<n> is the number of kilobytes) to check
3754 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
3755 and C<ulimit -d n>, respectively.
3757 =item Out of memory during %s extend
3759 (X) An attempt was made to extend an array, a list, or a string beyond
3760 the largest possible memory allocation.
3762 =item Out of memory during "large" request for %s
3764 (F) The malloc() function returned 0, indicating there was insufficient
3765 remaining memory (or virtual memory) to satisfy the request. However,
3766 the request was judged large enough (compile-time default is 64K), so a
3767 possibility to shut down by trapping this error is granted.
3769 =item Out of memory during request for %s
3771 (X)(F) The malloc() function returned 0, indicating there was
3772 insufficient remaining memory (or virtual memory) to satisfy the
3775 The request was judged to be small, so the possibility to trap it
3776 depends on the way perl was compiled. By default it is not trappable.
3777 However, if compiled for this, Perl may use the contents of C<$^M> as an
3778 emergency pool after die()ing with this message. In this case the error
3779 is trappable I<once>, and the error message will include the line and file
3780 where the failed request happened.
3782 =item Out of memory during ridiculously large request
3784 (F) You can't allocate more than 2^31+"small amount" bytes. This error
3785 is most likely to be caused by a typo in the Perl program. e.g.,
3786 C<$arr[time]> instead of C<$arr[$time]>.
3788 =item Out of memory for yacc stack
3790 (F) The yacc parser wanted to grow its stack so it could continue
3791 parsing, but realloc() wouldn't give it more memory, virtual or
3794 =item '.' outside of string in pack
3796 (F) The argument to a '.' in your template tried to move the working
3797 position to before the start of the packed string being built.
3799 =item '@' outside of string in unpack
3801 (F) You had a template that specified an absolute position outside
3802 the string being unpacked. See L<perlfunc/pack>.
3804 =item '@' outside of string with malformed UTF-8 in unpack
3806 (F) You had a template that specified an absolute position outside
3807 the string being unpacked. The string being unpacked was also invalid
3808 UTF-8. See L<perlfunc/pack>.
3810 =item overload arg '%s' is invalid
3812 (W overload) The L<overload> pragma was passed an argument it did not
3813 recognize. Did you mistype an operator?
3815 =item Overloaded dereference did not return a reference
3817 (F) An object with an overloaded dereference operator was dereferenced,
3818 but the overloaded operation did not return a reference. See
3821 =item Overloaded qr did not return a REGEXP
3823 (F) An object with a C<qr> overload was used as part of a match, but the
3824 overloaded operation didn't return a compiled regexp. See L<overload>.
3826 =item %s package attribute may clash with future reserved word: %s
3828 (W reserved) A lowercase attribute name was used that had a
3829 package-specific handler. That name might have a meaning to Perl itself
3830 some day, even though it doesn't yet. Perhaps you should use a
3831 mixed-case attribute name, instead. See L<attributes>.
3833 =item pack/unpack repeat count overflow
3835 (F) You can't specify a repeat count so large that it overflows your
3836 signed integers. See L<perlfunc/pack>.
3840 (W io) A single call to write() produced more lines than can fit on a
3841 page. See L<perlform>.
3845 (P) An internal error.
3847 =item panic: attempt to call %s in %s
3849 (P) One of the file test operators entered a code branch that calls
3850 an ACL related-function, but that function is not available on this
3851 platform. Earlier checks mean that it should not be possible to
3852 enter this branch on this platform.
3854 =item panic: child pseudo-process was never scheduled
3856 (P) A child pseudo-process in the ithreads implementation on Windows
3857 was not scheduled within the time period allowed and therefore was not
3858 able to initialize properly.
3860 =item panic: ck_grep, type=%u
3862 (P) Failed an internal consistency check trying to compile a grep.
3864 =item panic: ck_split, type=%u
3866 (P) Failed an internal consistency check trying to compile a split.
3868 =item panic: corrupt saved stack index %ld
3870 (P) The savestack was requested to restore more localized values than
3871 there are in the savestack.
3873 =item panic: del_backref
3875 (P) Failed an internal consistency check while trying to reset a weak
3880 (P) We popped the context stack to an eval context, and then discovered
3881 it wasn't an eval context.
3883 =item panic: do_subst
3885 (P) The internal pp_subst() routine was called with invalid operational
3888 =item panic: do_trans_%s
3890 (P) The internal do_trans routines were called with invalid operational
3893 =item panic: fold_constants JMPENV_PUSH returned %d
3895 (P) While attempting folding constants an exception other than an C<eval>
3900 (P) The library function frexp() failed, making printf("%f") impossible.
3902 =item panic: goto, type=%u, ix=%ld
3904 (P) We popped the context stack to a context with the specified label,
3905 and then discovered it wasn't a context we know how to do a goto in.
3907 =item panic: gp_free failed to free glob pointer
3909 (P) The internal routine used to clear a typeglob's entries tried
3910 repeatedly, but each time something re-created entries in the glob.
3911 Most likely the glob contains an object with a reference back to
3912 the glob and a destructor that adds a new object to the glob.
3914 =item panic: INTERPCASEMOD, %s
3916 (P) The lexer got into a bad state at a case modifier.
3918 =item panic: INTERPCONCAT, %s
3920 (P) The lexer got into a bad state parsing a string with brackets.
3922 =item panic: kid popen errno read
3924 (F) A forked child returned an incomprehensible message about its errno.
3926 =item panic: last, type=%u
3928 (P) We popped the context stack to a block context, and then discovered
3929 it wasn't a block context.
3931 =item panic: leave_scope clearsv
3933 (P) A writable lexical variable became read-only somehow within the
3936 =item panic: leave_scope inconsistency %u
3938 (P) The savestack probably got out of sync. At least, there was an
3939 invalid enum on the top of it.
3941 =item panic: magic_killbackrefs
3943 (P) Failed an internal consistency check while trying to reset all weak
3944 references to an object.
3946 =item panic: malloc, %s
3948 (P) Something requested a negative number of bytes of malloc.
3950 =item panic: memory wrap
3952 (P) Something tried to allocate either more memory than possible or a
3955 =item panic: pad_alloc, %p!=%p
3957 (P) The compiler got confused about which scratch pad it was allocating
3958 and freeing temporaries and lexicals from.
3960 =item panic: pad_free curpad, %p!=%p
3962 (P) The compiler got confused about which scratch pad it was allocating
3963 and freeing temporaries and lexicals from.
3965 =item panic: pad_free po
3967 (P) An invalid scratch pad offset was detected internally.
3969 =item panic: pad_reset curpad, %p!=%p
3971 (P) The compiler got confused about which scratch pad it was allocating
3972 and freeing temporaries and lexicals from.
3974 =item panic: pad_sv po
3976 (P) An invalid scratch pad offset was detected internally.
3978 =item panic: pad_swipe curpad, %p!=%p
3980 (P) The compiler got confused about which scratch pad it was allocating
3981 and freeing temporaries and lexicals from.
3983 =item panic: pad_swipe po
3985 (P) An invalid scratch pad offset was detected internally.
3987 =item panic: pp_iter, type=%u
3989 (P) The foreach iterator got called in a non-loop context frame.
3991 =item panic: pp_match%s
3993 (P) The internal pp_match() routine was called with invalid operational
3996 =item panic: pp_split, pm=%p, s=%p
3998 (P) Something terrible went wrong in setting up for the split.
4000 =item panic: realloc, %s
4002 (P) Something requested a negative number of bytes of realloc.
4004 =item panic: reference miscount on nsv in sv_replace() (%d != 1)
4006 (P) The internal sv_replace() function was handed a new SV with a
4007 reference count other than 1.
4009 =item panic: restartop in %s
4011 (P) Some internal routine requested a goto (or something like it), and
4012 didn't supply the destination.
4014 =item panic: return, type=%u
4016 (P) We popped the context stack to a subroutine or eval context, and
4017 then discovered it wasn't a subroutine or eval context.
4019 =item panic: scan_num, %s
4021 (P) scan_num() got called on something that wasn't a number.
4023 =item panic: Sequence (?{...}): no code block found in regex m/%s/
4025 (P) While compiling a pattern that has embedded (?{}) or (??{}) code
4026 blocks, perl couldn't locate the code block that should have already been
4027 seen and compiled by perl before control passed to the regex compiler.
4029 =item panic: strxfrm() gets absurd - a => %u, ab => %u
4031 (P) The interpreter's sanity check of the C function strxfrm() failed.
4032 In your current locale the returned transformation of the string "ab"
4033 is shorter than that of the string "a", which makes no sense.
4035 =item panic: sv_chop %s
4037 (P) The sv_chop() routine was passed a position that is not within the
4038 scalar's string buffer.
4040 =item panic: sv_insert, midend=%p, bigend=%p
4042 (P) The sv_insert() routine was told to remove more string than there
4045 =item panic: top_env
4047 (P) The compiler attempted to do a goto, or something weird like that.
4049 =item panic: unimplemented op %s (#%d) called
4051 (P) The compiler is screwed up and attempted to use an op that isn't
4052 permitted at run time.
4054 =item panic: utf16_to_utf8: odd bytelen
4056 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
4057 to even) byte length.
4059 =item panic: utf16_to_utf8_reversed: odd bytelen
4061 (P) Something tried to call utf16_to_utf8_reversed with an odd (as opposed
4062 to even) byte length.
4064 =item panic: yylex, %s
4066 (P) The lexer got into a bad state while processing a case modifier.
4068 =item Parentheses missing around "%s" list
4070 (W parenthesis) You said something like
4076 my ($foo, $bar) = @_;
4078 Remember that "my", "our", "local" and "state" bind tighter than comma.
4080 =item Parsing code internal error (%s)
4082 (F) Parsing code supplied by an extension violated the parser's API in
4085 =item Passing malformed UTF-8 to "%s" is deprecated
4087 (D deprecated, utf8) This message indicates a bug either in the Perl
4088 core or in XS code. Such code was trying to find out if a character,
4089 allegedly stored internally encoded as UTF-8, was of a given type, such
4090 as being punctuation or a digit. But the character was not encoded in
4091 legal UTF-8. The C<%s> is replaced by a string that can be used by
4092 knowledgeable people to determine what the type being checked against
4093 was. If C<utf8> warnings are enabled, a further message is raised,
4094 giving details of the malformation.
4096 =item Pattern subroutine nesting without pos change exceeded limit in regex
4098 (F) You used a pattern that uses too many nested subpattern calls without
4099 consuming any text. Restructure the pattern so text is consumed before
4100 the nesting limit is exceeded.
4102 =item C<-p> destination: %s
4104 (F) An error occurred during the implicit output invoked by the C<-p>
4105 command-line switch. (This output goes to STDOUT unless you've
4106 redirected it with select().)
4108 =item (perhaps you forgot to load "%s"?)
4110 (F) This is an educated guess made in conjunction with the message
4111 "Can't locate object method \"%s\" via package \"%s\"". It often means
4112 that a method requires a package that has not been loaded.
4114 =item Perl folding rules are not up-to-date for 0x%X; please use the perlbug
4115 utility to report; in regex; marked by S<<-- HERE> in m/%s/
4117 (S regexp) You used a regular expression with case-insensitive matching,
4118 and there is a bug in Perl in which the built-in regular expression
4119 folding rules are not accurate. This may lead to incorrect results.
4120 Please report this as a bug using the L<perlbug> utility.
4122 =item Perl_my_%s() not available
4124 (F) Your platform has very uncommon byte-order and integer size,
4125 so it was not possible to set up some or all fixed-width byte-order
4126 conversion functions. This is only a problem when you're using the
4127 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
4129 =item Perl %s required (did you mean %s?)--this is only %s, stopped
4131 (F) The code you are trying to run has asked for a newer version of
4132 Perl than you are running. Perhaps C<use 5.10> was written instead
4133 of C<use 5.010> or C<use v5.10>. Without the leading C<v>, the number is
4134 interpreted as a decimal, with every three digits after the
4135 decimal point representing a part of the version number. So 5.10
4136 is equivalent to v5.100.
4138 =item Perl %s required--this is only %s, stopped
4140 (F) The module in question uses features of a version of Perl more
4141 recent than the currently running version. How long has it been since
4142 you upgraded, anyway? See L<perlfunc/require>.
4144 =item PERL_SH_DIR too long
4146 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
4147 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
4149 =item PERL_SIGNALS illegal: "%s"
4151 (X) See L<perlrun/PERL_SIGNALS> for legal values.
4153 =item Perls since %s too modern--this is %s, stopped
4155 (F) The code you are trying to run claims it will not run
4156 on the version of Perl you are using because it is too new.
4157 Maybe the code needs to be updated, or maybe it is simply
4158 wrong and the version check should just be removed.
4160 =item perl: warning: Non hex character in '$ENV{PERL_HASH_SEED}', seed only partially set
4162 (S) PERL_HASH_SEED should match /^\s*(?:0x)?[0-9a-fA-F]+\s*\z/ but it
4163 contained a non hex character. This could mean you are not using the
4164 hash seed you think you are.
4166 =item perl: warning: Setting locale failed.
4168 (S) The whole warning message will look something like:
4170 perl: warning: Setting locale failed.
4171 perl: warning: Please check that your locale settings:
4174 are supported and installed on your system.
4175 perl: warning: Falling back to the standard locale ("C").
4177 Exactly what were the failed locale settings varies. In the above the
4178 settings were that the LC_ALL was "En_US" and the LANG had no value.
4179 This error means that Perl detected that you and/or your operating
4180 system supplier and/or system administrator have set up the so-called
4181 locale system but Perl could not use those settings. This was not
4182 dead serious, fortunately: there is a "default locale" called "C" that
4183 Perl can and will use, and the script will be run. Before you really
4184 fix the problem, however, you will get the same error message each
4185 time you run Perl. How to really fix the problem can be found in
4186 L<perllocale> section B<LOCALE PROBLEMS>.
4188 =item perl: warning: strange setting in '$ENV{PERL_PERTURB_KEYS}': '%s'
4190 (S) Perl was run with the environment variable PERL_PERTURB_KEYS defined
4191 but containing an unexpected value. The legal values of this setting
4194 Numeric | String | Result
4195 --------+---------------+-----------------------------------------
4196 0 | NO | Disables key traversal randomization
4197 1 | RANDOM | Enables full key traversal randomization
4198 2 | DETERMINISTIC | Enables repeatable key traversal
4201 Both numeric and string values are accepted, but note that string values are
4202 case sensitive. The default for this setting is "RANDOM" or 1.
4204 =item pid %x not a child
4206 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
4207 process which isn't a subprocess of the current process. While this is
4208 fine from VMS' perspective, it's probably not what you intended.
4210 =item 'P' must have an explicit size in unpack
4212 (F) The unpack format P must have an explicit size, not "*".
4214 =item pop on reference is experimental
4216 (S experimental::autoderef) C<pop> with a scalar argument is experimental
4217 and may change or be removed in a future Perl version. If you want to
4218 take the risk of using this feature, simply disable this warning:
4220 no warnings "experimental::autoderef";
4222 =item POSIX class [:%s:] unknown in regex; marked by S<< <-- HERE in m/%s/ >>
4224 (F) The class in the character class [: :] syntax is unknown. The S<<-- HERE>
4225 shows whereabouts in the regular expression the problem was discovered.
4226 Note that the POSIX character classes do B<not> have the C<is> prefix
4227 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
4228 not C<isprint>. See L<perlre>.
4230 =item POSIX getpgrp can't take an argument
4232 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
4233 the BSD version, which takes a pid.
4235 =item POSIX syntax [%c %c] belongs inside character classes in regex; marked by
4236 S<<-- HERE> in m/%s/
4238 (W regexp) The character class constructs [: :], [= =], and [. .] go
4239 I<inside> character classes, the [] are part of the construct, for example:
4240 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
4241 implemented; they are simply placeholders for future extensions and
4242 will cause fatal errors. The S<<-- HERE> shows whereabouts in the regular
4243 expression the problem was discovered. See L<perlre>.
4245 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by
4246 S<<-- HERE> in m/%s/
4248 (F) Within regular expression character classes ([]) the syntax beginning
4249 with "[." and ending with ".]" is reserved for future extensions. If you
4250 need to represent those character sequences inside a regular expression
4251 character class, just quote the square brackets with the backslash: "\[."
4252 and ".\]". The S<<-- HERE> shows whereabouts in the regular expression the
4253 problem was discovered. See L<perlre>.
4255 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by
4256 S<<-- HERE> in m/%s/
4258 (F) Within regular expression character classes ([]) the syntax beginning
4259 with "[=" and ending with "=]" is reserved for future extensions. If you
4260 need to represent those character sequences inside a regular expression
4261 character class, just quote the square brackets with the backslash: "\[="
4262 and "=\]". The S<<-- HERE> shows whereabouts in the regular expression the
4263 problem was discovered. See L<perlre>.
4265 =item Possible attempt to put comments in qw() list
4267 (W qw) qw() lists contain items separated by whitespace; as with literal
4268 strings, comment characters are not ignored, but are instead treated as
4269 literal data. (You may have used different delimiters than the
4270 parentheses shown here; braces are also frequently used.)
4272 You probably wrote something like this:
4279 when you should have written this:
4286 If you really want comments, build your list the
4287 old-fashioned way, with quotes and commas:
4291 'b', # another comment
4294 =item Possible attempt to separate words with commas
4296 (W qw) qw() lists contain items separated by whitespace; therefore
4297 commas aren't needed to separate the items. (You may have used
4298 different delimiters than the parentheses shown here; braces are also
4301 You probably wrote something like this:
4305 which puts literal commas into some of the list items. Write it without
4306 commas if you don't want them to appear in your data:
4310 =item Possible memory corruption: %s overflowed 3rd argument
4312 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
4313 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
4314 end of the buffer just in case. This sentinel byte got clobbered, and
4315 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
4317 =item Possible precedence issue with control flow operator
4319 (W syntax) There is a possible problem with the mixing of a control
4320 flow operator (e.g. C<return>) and a low-precedence operator like
4323 sub { return $a or $b; }
4327 sub { (return $a) or $b; }
4329 Which is effectively just:
4333 Either use parentheses or the high-precedence variant of the operator.
4335 Note this may be also triggered for constructs like:
4339 =item Possible precedence problem on bitwise %c operator
4341 (W precedence) Your program uses a bitwise logical operator in conjunction
4342 with a numeric comparison operator, like this :
4344 if ($x & $y == 0) { ... }
4346 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
4347 higher precedence of C<==>. This is probably not what you want. (If you
4348 really meant to write this, disable the warning, or, better, put the
4349 parentheses explicitly and write C<$x & ($y == 0)>).
4351 =item Possible unintended interpolation of $\ in regex
4353 (W ambiguous) You said something like C<m/$\/> in a regex.
4354 The regex C<m/foo$\s+bar/m> translates to: match the word 'foo', the output
4355 record separator (see L<perlvar/$\>) and the letter 's' (one time or more)
4356 followed by the word 'bar'.
4358 If this is what you intended then you can silence the warning by using
4359 C<m/${\}/> (for example: C<m/foo${\}s+bar/>).
4361 If instead you intended to match the word 'foo' at the end of the line
4362 followed by whitespace and the word 'bar' on the next line then you can use
4363 C<m/$(?)\/> (for example: C<m/foo$(?)\s+bar/>).
4365 =item Possible unintended interpolation of %s in string
4367 (W ambiguous) You said something like '@foo' in a double-quoted string
4368 but there was no array C<@foo> in scope at the time. If you wanted a
4369 literal @foo, then write it as \@foo; otherwise find out what happened
4370 to the array you apparently lost track of.
4372 =item Postfix dereference is experimental
4374 (S experimental::postderef) This warning is emitted if you use
4375 the experimental postfix dereference syntax. Simply suppress the
4376 warning if you want to use the feature, but know that in doing
4377 so you are taking the risk of using an experimental feature which
4378 may change or be removed in a future Perl version:
4380 no warnings "experimental::postderef";
4381 use feature "postderef", "postderef_qq";
4387 =item Precedence problem: open %s should be open(%s)
4389 (S precedence) The old irregular construct
4393 is now misinterpreted as
4397 because of the strict regularization of Perl 5's grammar into unary and
4398 list operators. (The old open was a little of both.) You must put
4399 parentheses around the filehandle, or use the new "or" operator instead
4402 =item Premature end of script headers
4406 =item printf() on closed filehandle %s
4408 (W closed) The filehandle you're writing to got itself closed sometime
4409 before now. Check your control flow.
4411 =item print() on closed filehandle %s
4413 (W closed) The filehandle you're printing on got itself closed sometime
4414 before now. Check your control flow.
4416 =item Process terminated by SIG%s
4418 (W) This is a standard message issued by OS/2 applications, while *nix
4419 applications die in silence. It is considered a feature of the OS/2
4420 port. One can easily disable this by appropriate sighandlers, see
4421 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
4424 =item Property '%s' is unknown in regex; marked by S<<-- HERE> in m/%s/
4426 (F) The named property which you specified via C<\p> or C<\P> is not one
4427 known to Perl. Perhaps you misspelled the name? See
4428 L<perluniprops/Properties accessible through \p{} and \P{}>
4429 for a complete list of available official
4430 properties. If it is a L<user-defined property|perlunicode/User-Defined Character Properties>
4431 it must have been defined by the time the regular expression is
4434 =item Prototype after '%c' for %s : %s
4436 (W illegalproto) A character follows % or @ in a prototype. This is
4437 useless, since % and @ gobble the rest of the subroutine arguments.
4439 =item Prototype mismatch: %s vs %s
4441 (S prototype) The subroutine being declared or defined had previously been
4442 declared or defined with a different function prototype.
4444 =item Prototype not terminated
4446 (F) You've omitted the closing parenthesis in a function prototype
4449 =item Prototype '%s' overridden by attribute 'prototype(%s)' in %s
4451 (W prototype) A prototype was declared in both the parentheses after
4452 the sub name and via the prototype attribute. The prototype in
4453 parentheses is useless, since it will be replaced by the prototype
4454 from the attribute before it's ever used.
4456 =item \p{} uses Unicode rules, not locale rules
4458 (W) You compiled a regular expression that contained a Unicode property
4459 match (C<\p> or C<\P>), but the regular expression is also being told to
4460 use the run-time locale, not Unicode. Instead, use a POSIX character
4461 class, which should know about the locale's rules.
4462 (See L<perlrecharclass/POSIX Character Classes>.)
4464 Even if the run-time locale is ISO 8859-1 (Latin1), which is a subset of
4465 Unicode, some properties will give results that are not valid for that
4468 Here are a couple of examples to help you see what's going on. If the
4469 locale is ISO 8859-7, the character at code point 0xD7 is the "GREEK
4470 CAPITAL LETTER CHI". But in Unicode that code point means the
4471 "MULTIPLICATION SIGN" instead, and C<\p> always uses the Unicode
4472 meaning. That means that C<\p{Alpha}> won't match, but C<[[:alpha:]]>
4473 should. Only in the Latin1 locale are all the characters in the same
4474 positions as they are in Unicode. But, even here, some properties give
4475 incorrect results. An example is C<\p{Changes_When_Uppercased}> which
4476 is true for "LATIN SMALL LETTER Y WITH DIAERESIS", but since the upper
4477 case of that character is not in Latin1, in that locale it doesn't
4478 change when upper cased.
4480 =item push on reference is experimental
4482 (S experimental::autoderef) C<push> with a scalar argument is experimental
4483 and may change or be removed in a future Perl version. If you want to
4484 take the risk of using this feature, simply disable this warning:
4486 no warnings "experimental::autoderef";
4488 =item Quantifier follows nothing in regex; marked by S<< <-- HERE in m/%s/ >>
4490 (F) You started a regular expression with a quantifier. Backslash it if
4491 you meant it literally. The S<<-- HERE> shows whereabouts in the regular
4492 expression the problem was discovered. See L<perlre>.
4494 =item Quantifier in {,} bigger than %d in regex; marked by S<<-- HERE> in
4497 (F) There is currently a limit to the size of the min and max values of
4498 the {min,max} construct. The S<<-- HERE> shows whereabouts in the regular
4499 expression the problem was discovered. See L<perlre>.
4501 =item Quantifier {n,m} with n > m can't match in regex
4503 =item Quantifier {n,m} with n > m can't match in regex; marked by
4504 S<<-- HERE> in m/%s/
4506 (W regexp) Minima should be less than or equal to maxima. If you really
4507 want your regexp to match something 0 times, just put {0}.
4509 =item Quantifier unexpected on zero-length expression in regex; marked by <--
4512 (W regexp) You applied a regular expression quantifier in a place where
4513 it makes no sense, such as on a zero-width assertion. Try putting the
4514 quantifier inside the assertion instead. For example, the way to match
4515 "abc" provided that it is followed by three repetitions of "xyz" is
4516 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
4518 The <-- HERE shows whereabouts in the regular expression the problem was
4521 =item Range iterator outside integer range
4523 (F) One (or both) of the numeric arguments to the range operator ".."
4524 are outside the range which can be represented by integers internally.
4525 One possible workaround is to force Perl to use magical string increment
4526 by prepending "0" to your numbers.
4528 =item readdir() attempted on invalid dirhandle %s
4530 (W io) The dirhandle you're reading from is either closed or not really
4531 a dirhandle. Check your control flow.
4533 =item readline() on closed filehandle %s
4535 (W closed) The filehandle you're reading from got itself closed sometime
4536 before now. Check your control flow.
4538 =item read() on closed filehandle %s
4540 (W closed) You tried to read from a closed filehandle.
4542 =item read() on unopened filehandle %s
4544 (W unopened) You tried to read from a filehandle that was never opened.
4546 =item Reallocation too large: %x
4548 (F) You can't allocate more than 64K on an MS-DOS machine.
4550 =item realloc() of freed memory ignored
4552 (S malloc) An internal routine called realloc() on something that had
4555 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
4557 (S debugging) You can't use the B<-D> option unless the code to produce
4558 the desired output is compiled into Perl, which entails some overhead,
4559 which is why it's currently left out of your copy.
4561 =item Recursive call to Perl_load_module in PerlIO_find_layer
4563 (P) It is currently not permitted to load modules when creating
4564 a filehandle inside an %INC hook. This can happen with C<open my
4565 $fh, '<', \$scalar>, which implicitly loads PerlIO::scalar. Try
4566 loading PerlIO::scalar explicitly first.
4568 =item Recursive inheritance detected in package '%s'
4570 (F) While calculating the method resolution order (MRO) of a package, Perl
4571 believes it found an infinite loop in the C<@ISA> hierarchy. This is a
4572 crude check that bails out after 100 levels of C<@ISA> depth.
4574 =item refcnt_dec: fd %d%s
4576 =item refcnt: fd %d%s
4578 =item refcnt_inc: fd %d%s
4580 (P) Perl's I/O implementation failed an internal consistency check. If
4581 you see this message, something is very wrong.
4583 =item Reference found where even-sized list expected
4585 (W misc) You gave a single reference where Perl was expecting a list
4586 with an even number of elements (for assignment to a hash). This
4587 usually means that you used the anon hash constructor when you meant
4588 to use parens. In any case, a hash requires key/value B<pairs>.
4590 %hash = { one => 1, two => 2, }; # WRONG
4591 %hash = [ qw/ an anon array / ]; # WRONG
4592 %hash = ( one => 1, two => 2, ); # right
4593 %hash = qw( one 1 two 2 ); # also fine
4595 =item Reference is already weak
4597 (W misc) You have attempted to weaken a reference that is already weak.
4598 Doing so has no effect.
4600 =item Reference to invalid group 0 in regex; marked by S<<-- HERE> in m/%s/
4602 (F) You used C<\g0> or similar in a regular expression. You may refer
4603 to capturing parentheses only with strictly positive integers
4604 (normal backreferences) or with strictly negative integers (relative
4605 backreferences). Using 0 does not make sense.
4607 =item Reference to nonexistent group in regex; marked by S<<-- HERE> in
4610 (F) You used something like C<\7> in your regular expression, but there are
4611 not at least seven sets of capturing parentheses in the expression. If
4612 you wanted to have the character with ordinal 7 inserted into the regular
4613 expression, prepend zeroes to make it three digits long: C<\007>
4615 The <-- HERE shows whereabouts in the regular expression the problem was
4618 =item Reference to nonexistent named group in regex; marked by S<<-- HERE>
4621 (F) You used something like C<\k'NAME'> or C<< \k<NAME> >> in your regular
4622 expression, but there is no corresponding named capturing parentheses
4623 such as C<(?'NAME'...)> or C<< (?<NAME>...) >>. Check if the name has been
4624 spelled correctly both in the backreference and the declaration.
4626 The <-- HERE shows whereabouts in the regular expression the problem was
4629 =item Reference to nonexistent or unclosed group in regex; marked by
4630 S<<-- HERE> in m/%s/
4632 (F) You used something like C<\g{-7}> in your regular expression, but there
4633 are not at least seven sets of closed capturing parentheses in the
4634 expression before where the C<\g{-7}> was located.
4636 The <-- HERE shows whereabouts in the regular expression the problem was
4639 =item regexp memory corruption
4641 (P) The regular expression engine got confused by what the regular
4642 expression compiler gave it.
4644 =item Regexp modifier "/%c" may appear a maximum of twice
4646 =item Regexp modifier "%c" may appear a maximum of twice in regex; marked
4647 by S<<-- HERE> in m/%s/
4649 (F) The regular expression pattern had too many occurrences
4650 of the specified modifier. Remove the extraneous ones.
4652 =item Regexp modifier "%c" may not appear after the "-" in regex; marked by <--
4655 (F) Turning off the given modifier has the side effect of turning on
4656 another one. Perl currently doesn't allow this. Reword the regular
4657 expression to use the modifier you want to turn on (and place it before
4658 the minus), instead of the one you want to turn off.
4660 =item Regexp modifier "/%c" may not appear twice
4662 =item Regexp modifier "%c" may not appear twice in regex; marked by <--
4665 (F) The regular expression pattern had too many occurrences
4666 of the specified modifier. Remove the extraneous ones.
4668 =item Regexp modifiers "/%c" and "/%c" are mutually exclusive
4670 =item Regexp modifiers "%c" and "%c" are mutually exclusive in regex;
4671 marked by S<<-- HERE> in m/%s/
4673 (F) The regular expression pattern had more than one of these
4674 mutually exclusive modifiers. Retain only the modifier that is
4675 supposed to be there.
4677 =item Regexp out of space in regex m/%s/
4679 (P) A "can't happen" error, because safemalloc() should have caught it
4682 =item Repeated format line will never terminate (~~ and @#)
4684 (F) Your format contains the ~~ repeat-until-blank sequence and a
4685 numeric field that will never go blank so that the repetition never
4686 terminates. You might use ^# instead. See L<perlform>.
4688 =item Replacement list is longer than search list
4690 (W misc) You have used a replacement list that is longer than the
4691 search list. So the additional elements in the replacement list
4694 =item '%s' resolved to '\o{%s}%d'
4696 (W misc, regexp) You wrote something like C<\08>, or C<\179> in a
4697 double-quotish string. All but the last digit is treated as a single
4698 character, specified in octal. The last digit is the next character in
4699 the string. To tell Perl that this is indeed what you want, you can use
4700 the C<\o{ }> syntax, or use exactly three digits to specify the octal
4703 =item Reversed %s= operator
4705 (W syntax) You wrote your assignment operator backwards. The = must
4706 always come last, to avoid ambiguity with subsequent unary operators.
4708 =item rewinddir() attempted on invalid dirhandle %s
4710 (W io) The dirhandle you tried to do a rewinddir() on is either closed or not
4711 really a dirhandle. Check your control flow.
4713 =item Scalars leaked: %d
4715 (S internal) Something went wrong in Perl's internal bookkeeping
4716 of scalars: not all scalar variables were deallocated by the time
4717 Perl exited. What this usually indicates is a memory leak, which
4718 is of course bad, especially if the Perl program is intended to be
4721 =item Scalar value @%s[%s] better written as $%s[%s]
4723 (W syntax) You've used an array slice (indicated by @) to select a
4724 single element of an array. Generally it's better to ask for a scalar
4725 value (indicated by $). The difference is that C<$foo[&bar]> always
4726 behaves like a scalar, both when assigning to it and when evaluating its
4727 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
4728 and provides a list context to its subscript, which can do weird things
4729 if you're expecting only one subscript.
4731 On the other hand, if you were actually hoping to treat the array
4732 element as a list, you need to look into how references work, because
4733 Perl will not magically convert between scalars and lists for you. See
4736 =item Scalar value @%s{%s} better written as $%s{%s}
4738 (W syntax) You've used a hash slice (indicated by @) to select a single
4739 element of a hash. Generally it's better to ask for a scalar value
4740 (indicated by $). The difference is that C<$foo{&bar}> always behaves
4741 like a scalar, both when assigning to it and when evaluating its
4742 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
4743 and provides a list context to its subscript, which can do weird things
4744 if you're expecting only one subscript.
4746 On the other hand, if you were actually hoping to treat the hash element
4747 as a list, you need to look into how references work, because Perl will
4748 not magically convert between scalars and lists for you. See
4751 =item Search pattern not terminated
4753 (F) The lexer couldn't find the final delimiter of a // or m{}
4754 construct. Remember that bracketing delimiters count nesting level.
4755 Missing the leading C<$> from a variable C<$m> may cause this error.
4757 Note that since Perl 5.9.0 a // can also be the I<defined-or>
4758 construct, not just the empty search pattern. Therefore code written
4759 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
4760 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
4762 =item Search pattern not terminated or ternary operator parsed as search pattern
4764 (F) The lexer couldn't find the final delimiter of a C<?PATTERN?>
4767 The question mark is also used as part of the ternary operator (as in
4768 C<foo ? 0 : 1>) leading to some ambiguous constructions being wrongly
4769 parsed. One way to disambiguate the parsing is to put parentheses around
4770 the conditional expression, i.e. C<(foo) ? 0 : 1>.
4772 =item seekdir() attempted on invalid dirhandle %s
4774 (W io) The dirhandle you are doing a seekdir() on is either closed or not
4775 really a dirhandle. Check your control flow.
4777 =item %sseek() on unopened filehandle
4779 (W unopened) You tried to use the seek() or sysseek() function on a
4780 filehandle that was either never opened or has since been closed.
4782 =item select not implemented
4784 (F) This machine doesn't implement the select() system call.
4786 =item Self-ties of arrays and hashes are not supported
4788 (F) Self-ties are of arrays and hashes are not supported in
4789 the current implementation.
4791 =item Semicolon seems to be missing
4793 (W semicolon) A nearby syntax error was probably caused by a missing
4794 semicolon, or possibly some other missing operator, such as a comma.
4796 =item semi-panic: attempt to dup freed string
4798 (S internal) The internal newSVsv() routine was called to duplicate a
4799 scalar that had previously been marked as free.
4801 =item sem%s not implemented
4803 (F) You don't have System V semaphore IPC on your system.
4805 =item send() on closed socket %s
4807 (W closed) The socket you're sending to got itself closed sometime
4808 before now. Check your control flow.
4810 =item Sequence (? incomplete in regex; marked by S<<-- HERE> in m/%s/
4812 (F) A regular expression ended with an incomplete extension (?. The
4813 S<<-- HERE> shows whereabouts in the regular expression the problem was
4814 discovered. See L<perlre>.
4816 =item Sequence (?%c...) not implemented in regex; marked by S<<-- HERE> in
4819 (F) A proposed regular expression extension has the character reserved
4820 but has not yet been written. The S<<-- HERE> shows whereabouts in the
4821 regular expression the problem was discovered. See L<perlre>.
4823 =item Sequence (?%s...) not recognized in regex; marked by S<<-- HERE> in
4826 (F) You used a regular expression extension that doesn't make sense.
4827 The S<<-- HERE> shows whereabouts in the regular expression the problem was
4828 discovered. This may happen when using the C<(?^...)> construct to tell
4829 Perl to use the default regular expression modifiers, and you
4830 redundantly specify a default modifier. For other
4831 causes, see L<perlre>.
4833 =item Sequence (?#... not terminated in regex m/%s/
4835 (F) A regular expression comment must be terminated by a closing
4836 parenthesis. Embedded parentheses aren't allowed. See
4839 =item Sequence (?&... not terminated in regex; marked by S<<-- HERE> in
4842 (F) A named reference of the form C<(?&...)> was missing the final
4843 closing parenthesis after the name. The S<<-- HERE> shows whereabouts
4844 in the regular expression the problem was discovered.
4846 =item Sequence (?%c... not terminated in regex; marked by S<<-- HERE>
4849 (F) A named group of the form C<(?'...')> or C<< (?<...>) >> was missing the final
4850 closing quote or angle bracket. The S<<-- HERE> shows whereabouts in the
4851 regular expression the problem was discovered.
4853 =item Sequence (?(%c... not terminated in regex; marked by S<<-- HERE>
4856 (F) A named reference of the form C<(?('...')...)> or C<< (?(<...>)...) >> was
4857 missing the final closing quote or angle bracket after the name. The
4858 S<<-- HERE> shows whereabouts in the regular expression the problem was
4861 =item Sequence \%s... not terminated in regex; marked by S<<-- HERE> in
4864 (F) The regular expression expects a mandatory argument following the escape
4865 sequence and this has been omitted or incorrectly written.
4867 =item Sequence (?{...}) not terminated with ')'
4869 (F) The end of the perl code contained within the {...} must be
4870 followed immediately by a ')'.
4872 =item Sequence ?P=... not terminated in regex; marked by S<<-- HERE> in
4875 (F) A named reference of the form C<(?P=...)> was missing the final
4876 closing parenthesis after the name. The S<<-- HERE> shows whereabouts
4877 in the regular expression the problem was discovered.
4879 =item Sequence (?R) not terminated in regex m/%s/
4881 (F) An C<(?R)> or C<(?0)> sequence in a regular expression was missing the
4884 =item Server error (a.k.a. "500 Server error")
4886 (A) This is the error message generally seen in a browser window
4887 when trying to run a CGI program (including SSI) over the web. The
4888 actual error text varies widely from server to server. The most
4889 frequently-seen variants are "500 Server error", "Method (something)
4890 not permitted", "Document contains no data", "Premature end of script
4891 headers", and "Did not produce a valid header".
4893 B<This is a CGI error, not a Perl error>.
4895 You need to make sure your script is executable, is accessible by
4896 the user CGI is running the script under (which is probably not the
4897 user account you tested it under), does not rely on any environment
4898 variables (like PATH) from the user it isn't running under, and isn't
4899 in a location where the CGI server can't find it, basically, more or
4900 less. Please see the following for more information:
4902 http://www.perl.org/CGI_MetaFAQ.html
4903 http://www.htmlhelp.org/faq/cgifaq.html
4904 http://www.w3.org/Security/Faq/
4906 You should also look at L<perlfaq9>.
4908 =item Setting $/ to a reference to %s as a form of slurp is deprecated, treating as undef
4910 (W deprecated) You assigned a reference to a scalar to C<$/> where the
4911 referenced item is not a positive integer. In older perls this B<appeared>
4912 to work the same as setting it to C<undef> but was in fact internally
4913 different, less efficient and with very bad luck could have resulted in
4914 your file being split by a stringified form of the reference.
4916 In Perl 5.19.9 this was changed so that it would be B<exactly> the same as
4917 setting C<$/> to undef, with the exception that this warning would be
4920 You are recommended to change your code to set C<$/> to C<undef>
4921 explicitly if you wish to slurp the file. In future versions of Perl
4922 assigning a reference to will throw a fatal error.
4924 =item Setting $/ to a %s reference is forbidden
4926 (F) You tried to assign a reference to a non integer to C<$/>. In older
4927 Perls this would have behaved similarly to setting it to a reference
4928 to a positive integer, where the integer was the address of the reference.
4929 As of Perl 5.19.9 this is a fatal error, to allow future versions of Perl
4930 to use non integer refs for more interesting purposes.
4932 =item setegid() not implemented
4934 (F) You tried to assign to C<$)>, and your operating system doesn't
4935 support the setegid() system call (or equivalent), or at least Configure
4938 =item seteuid() not implemented
4940 (F) You tried to assign to C<< $> >>, and your operating system doesn't
4941 support the seteuid() system call (or equivalent), or at least Configure
4944 =item setpgrp can't take arguments
4946 (F) Your system has the setpgrp() from BSD 4.2, which takes no
4947 arguments, unlike POSIX setpgid(), which takes a process ID and process
4950 =item setrgid() not implemented
4952 (F) You tried to assign to C<$(>, and your operating system doesn't
4953 support the setrgid() system call (or equivalent), or at least Configure
4956 =item setruid() not implemented
4958 (F) You tried to assign to C<$<>, and your operating system doesn't
4959 support the setruid() system call (or equivalent), or at least Configure
4962 =item setsockopt() on closed socket %s
4964 (W closed) You tried to set a socket option on a closed socket. Did you
4965 forget to check the return value of your socket() call? See
4966 L<perlfunc/setsockopt>.
4968 =item shift on reference is experimental
4970 (S experimental::autoderef) C<shift> with a scalar argument is experimental
4971 and may change or be removed in a future Perl version. If you want to
4972 take the risk of using this feature, simply disable this warning:
4974 no warnings "experimental::autoderef";
4976 =item shm%s not implemented
4978 (F) You don't have System V shared memory IPC on your system.
4980 =item !=~ should be !~
4982 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
4983 interpreted as the != (numeric not equal) and ~ (1's complement)
4984 operators: probably not what you intended.
4986 =item <> should be quotes
4988 (F) You wrote C<< require <file> >> when you should have written
4991 =item /%s/ should probably be written as "%s"
4993 (W syntax) You have used a pattern where Perl expected to find a string,
4994 as in the first argument to C<join>. Perl will treat the true or false
4995 result of matching the pattern against $_ as the string, which is
4996 probably not what you had in mind.
4998 =item shutdown() on closed socket %s
5000 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
5003 =item SIG%s handler "%s" not defined
5005 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
5006 Perhaps you put it into the wrong package?
5008 =item Slab leaked from cv %p
5010 (S) If you see this message, then something is seriously wrong with the
5011 internal bookkeeping of op trees. An op tree needed to be freed after
5012 a compilation error, but could not be found, so it was leaked instead.
5014 =item sleep(%u) too large
5016 (W overflow) You called C<sleep> with a number that was larger than
5017 it can reliably handle and C<sleep> probably slept for less time than
5020 =item Smart matching a non-overloaded object breaks encapsulation
5022 (F) You should not use the C<~~> operator on an object that does not
5023 overload it: Perl refuses to use the object's underlying structure
5024 for the smart match.
5026 =item Smartmatch is experimental
5028 (S experimental::smartmatch) This warning is emitted if you
5029 use the smartmatch (C<~~>) operator. This is currently an experimental
5030 feature, and its details are subject to change in future releases of
5031 Perl. Particularly, its current behavior is noticed for being
5032 unnecessarily complex and unintuitive, and is very likely to be
5035 =item sort is now a reserved word
5037 (F) An ancient error message that almost nobody ever runs into anymore.
5038 But before sort was a keyword, people sometimes used it as a filehandle.
5040 =item Sort subroutine didn't return single value
5042 (F) A sort comparison subroutine written in XS must return exactly one
5043 item. See L<perlfunc/sort>.
5045 =item Source filters apply only to byte streams
5047 (F) You tried to activate a source filter (usually by loading a
5048 source filter module) within a string passed to C<eval>. This is
5049 not permitted under the C<unicode_eval> feature. Consider using
5050 C<evalbytes> instead. See L<feature>.
5052 =item splice() offset past end of array
5054 (W misc) You attempted to specify an offset that was past the end of
5055 the array passed to splice(). Splicing will instead commence at the
5056 end of the array, rather than past it. If this isn't what you want,
5057 try explicitly pre-extending the array by assigning $#array = $offset.
5058 See L<perlfunc/splice>.
5060 =item splice on reference is experimental
5062 (S experimental::autoderef) C<splice> with a scalar argument
5063 is experimental and may change or be removed in a future
5064 Perl version. If you want to take the risk of using this
5065 feature, simply disable this warning:
5067 no warnings "experimental::autoderef";
5071 (P) The split was looping infinitely. (Obviously, a split shouldn't
5072 iterate more times than there are characters of input, which is what
5073 happened.) See L<perlfunc/split>.
5075 =item Statement unlikely to be reached
5077 (W exec) You did an exec() with some statement after it other than a
5078 die(). This is almost always an error, because exec() never returns
5079 unless there was a failure. You probably wanted to use system()
5080 instead, which does return. To suppress this warning, put the exec() in
5083 =item "state %s" used in sort comparison
5085 (W syntax) The package variables $a and $b are used for sort comparisons.
5086 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
5087 sort comparison block, and the variable had earlier been declared as a
5088 lexical variable. Either qualify the sort variable with the package
5089 name, or rename the lexical variable.
5091 =item "state" variable %s can't be in a package
5093 (F) Lexically scoped variables aren't in a package, so it doesn't make
5094 sense to try to declare one with a package qualifier on the front. Use
5095 local() if you want to localize a package variable.
5097 =item stat() on unopened filehandle %s
5099 (W unopened) You tried to use the stat() function on a filehandle that
5100 was either never opened or has since been closed.
5102 =item Strings with code points over 0xFF may not be mapped into in-memory file handles
5104 (W utf8) You tried to open a reference to a scalar for read or append
5105 where the scalar contained code points over 0xFF. In-memory files
5106 model on-disk files and can only contain bytes.
5108 =item Stub found while resolving method "%s" overloading "%s" in package "%s"
5110 (P) Overloading resolution over @ISA tree may be broken by importation
5111 stubs. Stubs should never be implicitly created, but explicit calls to
5112 C<can> may break this.
5114 =item Subroutine "&%s" is not available
5116 (W closure) During compilation, an inner named subroutine or eval is
5117 attempting to capture an outer lexical subroutine that is not currently
5118 available. This can happen for one of two reasons. First, the lexical
5119 subroutine may be declared in an outer anonymous subroutine that has
5120 not yet been created. (Remember that named subs are created at compile
5121 time, while anonymous subs are created at run-time.) For example,
5123 sub { my sub a {...} sub f { \&a } }
5125 At the time that f is created, it can't capture the current "a" sub,
5126 since the anonymous subroutine hasn't been created yet. Conversely, the
5127 following won't give a warning since the anonymous subroutine has by now
5128 been created and is live:
5130 sub { my sub a {...} eval 'sub f { \&a }' }->();
5132 The second situation is caused by an eval accessing a lexical subroutine
5133 that has gone out of scope, for example,
5141 Here, when the '\&a' in the eval is being compiled, f() is not currently
5142 being executed, so its &a is not available for capture.
5144 =item "%s" subroutine &%s masks earlier declaration in same %s
5146 (W misc) A "my" or "state" subroutine has been redeclared in the
5147 current scope or statement, effectively eliminating all access to
5148 the previous instance. This is almost always a typographical error.
5149 Note that the earlier subroutine will still exist until the end of
5150 the scope or until all closure references to it are destroyed.
5152 =item Subroutine %s redefined
5154 (W redefine) You redefined a subroutine. To suppress this warning, say
5157 no warnings 'redefine';
5158 eval "sub name { ... }";
5161 =item Substitution loop
5163 (P) The substitution was looping infinitely. (Obviously, a substitution
5164 shouldn't iterate more times than there are characters of input, which
5165 is what happened.) See the discussion of substitution in
5166 L<perlop/"Regexp Quote-Like Operators">.
5168 =item Substitution pattern not terminated
5170 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
5171 construct. Remember that bracketing delimiters count nesting level.
5172 Missing the leading C<$> from variable C<$s> may cause this error.
5174 =item Substitution replacement not terminated
5176 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
5177 construct. Remember that bracketing delimiters count nesting level.
5178 Missing the leading C<$> from variable C<$s> may cause this error.
5180 =item substr outside of string
5182 (W substr)(F) You tried to reference a substr() that pointed outside of
5183 a string. That is, the absolute value of the offset was larger than the
5184 length of the string. See L<perlfunc/substr>. This warning is fatal if
5185 substr is used in an lvalue context (as the left hand side of an
5186 assignment or as a subroutine argument for example).
5188 =item sv_upgrade from type %d down to type %d
5190 (P) Perl tried to force the upgrade of an SV to a type which was actually
5191 inferior to its current type.
5193 =item SWASHNEW didn't return an HV ref
5195 (P) Something went wrong internally when Perl was trying to look up
5198 =item Switch (?(condition)... contains too many branches in regex; marked by
5199 S<<-- HERE> in m/%s/
5201 (F) A (?(condition)if-clause|else-clause) construct can have at most
5202 two branches (the if-clause and the else-clause). If you want one or
5203 both to contain alternation, such as using C<this|that|other>, enclose
5204 it in clustering parentheses:
5206 (?(condition)(?:this|that|other)|else-clause)
5208 The S<<-- HERE> shows whereabouts in the regular expression the problem
5209 was discovered. See L<perlre>.
5211 =item Switch condition not recognized in regex; marked by S<<-- HERE> in
5214 (F) The condition part of a (?(condition)if-clause|else-clause) construct
5215 is not known. The condition must be one of the following:
5217 (1) (2) ... true if 1st, 2nd, etc., capture matched
5218 (<NAME>) ('NAME') true if named capture matched
5219 (?=...) (?<=...) true if subpattern matches
5220 (?!...) (?<!...) true if subpattern fails to match
5221 (?{ CODE }) true if code returns a true value
5222 (R) true if evaluating inside recursion
5223 (R1) (R2) ... true if directly inside capture group 1, 2, etc.
5224 (R&NAME) true if directly inside named capture
5225 (DEFINE) always false; for defining named subpatterns
5227 The <-- HERE shows whereabouts in the regular expression the problem was
5228 discovered. See L<perlre>.
5230 =item switching effective %s is not implemented
5232 (F) While under the C<use filetest> pragma, we cannot switch the real
5233 and effective uids or gids.
5237 (F) Probably means you had a syntax error. Common reasons include:
5239 A keyword is misspelled.
5240 A semicolon is missing.
5242 An opening or closing parenthesis is missing.
5243 An opening or closing brace is missing.
5244 A closing quote is missing.
5246 Often there will be another error message associated with the syntax
5247 error giving more information. (Sometimes it helps to turn on B<-w>.)
5248 The error message itself often tells you where it was in the line when
5249 it decided to give up. Sometimes the actual error is several tokens
5250 before this, because Perl is good at understanding random input.
5251 Occasionally the line number may be misleading, and once in a blue moon
5252 the only way to figure out what's triggering the error is to call
5253 C<perl -c> repeatedly, chopping away half the program each time to see
5254 if the error went away. Sort of the cybernetic version of S<20 questions>.
5256 =item syntax error at line %d: '%s' unexpected
5258 (A) You've accidentally run your script through the Bourne shell instead
5259 of Perl. Check the #! line, or manually feed your script into Perl
5262 =item syntax error in file %s at line %d, next 2 tokens "%s"
5264 (F) This error is likely to occur if you run a perl5 script through
5265 a perl4 interpreter, especially if the next 2 tokens are "use strict"
5266 or "my $var" or "our $var".
5268 =item Syntax error in (?[...]) in regex m/%s/
5270 (F) Perl could not figure out what you meant inside this construct; this
5271 notifies you that it is giving up trying.
5275 (F) The final summary message when a C<perl -c> succeeds.
5277 =item sysread() on closed filehandle %s
5279 (W closed) You tried to read from a closed filehandle.
5281 =item sysread() on unopened filehandle %s
5283 (W unopened) You tried to read from a filehandle that was never opened.
5285 =item System V %s is not implemented on this machine
5287 (F) You tried to do something with a function beginning with "sem",
5288 "shm", or "msg" but that System V IPC is not implemented in your
5289 machine. In some machines the functionality can exist but be
5290 unconfigured. Consult your system support.
5292 =item syswrite() on closed filehandle %s
5294 (W closed) The filehandle you're writing to got itself closed sometime
5295 before now. Check your control flow.
5297 =item C<-T> and C<-B> not implemented on filehandles
5299 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
5300 know about your kind of stdio. You'll have to use a filename instead.
5302 =item Target of goto is too deeply nested
5304 (F) You tried to use C<goto> to reach a label that was too deeply nested
5305 for Perl to reach. Perl is doing you a favor by refusing.
5307 =item telldir() attempted on invalid dirhandle %s
5309 (W io) The dirhandle you tried to telldir() is either closed or not really
5310 a dirhandle. Check your control flow.
5312 =item tell() on unopened filehandle
5314 (W unopened) You tried to use the tell() function on a filehandle that
5315 was either never opened or has since been closed.
5317 =item That use of $[ is unsupported
5319 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
5320 as a compiler directive. You may say only one of
5329 This is to prevent the problem of one module changing the array base out
5330 from under another module inadvertently. See L<perlvar/$[> and L<arybase>.
5332 =item The crypt() function is unimplemented due to excessive paranoia.
5334 (F) Configure couldn't find the crypt() function on your machine,
5335 probably because your vendor didn't supply it, probably because they
5336 think the U.S. Government thinks it's a secret, or at least that they
5337 will continue to pretend that it is. And if you quote me on that, I
5340 =item The %s function is unimplemented
5342 (F) The function indicated isn't implemented on this architecture,
5343 according to the probings of Configure.
5345 =item The lexical_subs feature is experimental
5347 (S experimental::lexical_subs) This warning is emitted if you
5348 declare a sub with C<my> or C<state>. Simply suppress the warning
5349 if you want to use the feature, but know that in doing so you
5350 are taking the risk of using an experimental feature which may
5351 change or be removed in a future Perl version:
5353 no warnings "experimental::lexical_subs";
5354 use feature "lexical_subs";
5357 =item The regex_sets feature is experimental
5359 (S experimental::regex_sets) This warning is emitted if you
5360 use the syntax S<C<(?[ ])>> in a regular expression.
5361 The details of this feature are subject to change.
5362 if you want to use it, but know that in doing so you
5363 are taking the risk of using an experimental feature which may
5364 change in a future Perl version, you can do this to silence the
5367 no warnings "experimental::regex_sets";
5369 =item The stat preceding %s wasn't an lstat
5371 (F) It makes no sense to test the current stat buffer for symbolic
5372 linkhood if the last stat that wrote to the stat buffer already went
5373 past the symlink to get to the real file. Use an actual filename
5376 =item The 'unique' attribute may only be applied to 'our' variables
5378 (F) This attribute was never supported on C<my> or C<sub> declarations.
5380 =item This Perl can't reset CRTL environ elements (%s)
5382 =item This Perl can't set CRTL environ elements (%s=%s)
5384 (W internal) Warnings peculiar to VMS. You tried to change or delete an
5385 element of the CRTL's internal environ array, but your copy of Perl
5386 wasn't built with a CRTL that contained the setenv() function. You'll
5387 need to rebuild Perl with a CRTL that does, or redefine
5388 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
5389 target of the change to
5390 %ENV which produced the warning.
5392 =item This Perl has not been built with support for randomized hash key traversal but something called Perl_hv_rand_set().
5394 (F) Something has attempted to use an internal API call which
5395 depends on Perl being compiled with the default support for randomized hash
5396 key traversal, but this Perl has been compiled without it. You should
5397 report this warning to the relevant upstream party, or recompile perl
5398 with default options.
5400 =item times not implemented
5402 (F) Your version of the C library apparently doesn't do times(). I
5403 suspect you're not running on Unix.
5405 =item "-T" is on the #! line, it must also be used on the command line
5407 (X) The #! line (or local equivalent) in a Perl script contains
5408 the B<-T> option (or the B<-t> option), but Perl was not invoked with
5409 B<-T> in its command line. This is an error because, by the time
5410 Perl discovers a B<-T> in a script, it's too late to properly taint
5411 everything from the environment. So Perl gives up.
5413 If the Perl script is being executed as a command using the #!
5414 mechanism (or its local equivalent), this error can usually be
5415 fixed by editing the #! line so that the B<-%c> option is a part of
5416 Perl's first argument: e.g. change C<perl -n -%c> to C<perl -%c -n>.
5418 If the Perl script is being executed as C<perl scriptname>, then the
5419 B<-%c> option must appear on the command line: C<perl -%c scriptname>.
5421 =item To%s: illegal mapping '%s'
5423 (F) You tried to define a customized To-mapping for lc(), lcfirst,
5424 uc(), or ucfirst() (or their string-inlined versions), but you
5425 specified an illegal mapping.
5426 See L<perlunicode/"User-Defined Character Properties">.
5428 =item Too deeply nested ()-groups
5430 (F) Your template contains ()-groups with a ridiculously deep nesting level.
5432 =item Too few args to syscall
5434 (F) There has to be at least one argument to syscall() to specify the
5435 system call to call, silly dilly.
5437 =item Too late for "-%s" option
5439 (X) The #! line (or local equivalent) in a Perl script contains the
5440 B<-M>, B<-m> or B<-C> option.
5442 In the case of B<-M> and B<-m>, this is an error because those options
5443 are not intended for use inside scripts. Use the C<use> pragma instead.
5445 The B<-C> option only works if it is specified on the command line as
5446 well (with the same sequence of letters or numbers following). Either
5447 specify this option on the command line, or, if your system supports
5448 it, make your script executable and run it directly instead of passing
5451 =item Too late to run %s block
5453 (W void) A CHECK or INIT block is being defined during run time proper,
5454 when the opportunity to run them has already passed. Perhaps you are
5455 loading a file with C<require> or C<do> when you should be using C<use>
5456 instead. Or perhaps you should put the C<require> or C<do> inside a
5459 =item Too many args to syscall
5461 (F) Perl supports a maximum of only 14 args to syscall().
5463 =item Too many arguments for %s
5465 (F) The function requires fewer arguments than you specified.
5469 (A) You've accidentally run your script through B<csh> instead of Perl.
5470 Check the #! line, or manually feed your script into Perl yourself.
5474 (A) You've accidentally run your script through B<csh> instead of Perl.
5475 Check the #! line, or manually feed your script into Perl yourself.
5477 =item Trailing \ in regex m/%s/
5479 (F) The regular expression ends with an unbackslashed backslash.
5480 Backslash it. See L<perlre>.
5482 =item Trailing white-space in a charnames alias definition is deprecated
5484 (D deprecated) You defined a character name which ended in a space
5485 character. Remove the trailing space(s). Usually these names are
5486 defined in the C<:alias> import argument to C<use charnames>, but they
5487 could be defined by a translator installed into C<$^H{charnames}>.
5488 See L<charnames/CUSTOM ALIASES>.
5490 =item Transliteration pattern not terminated
5492 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
5493 or y/// or y[][] construct. Missing the leading C<$> from variables
5494 C<$tr> or C<$y> may cause this error.
5496 =item Transliteration replacement not terminated
5498 (F) The lexer couldn't find the final delimiter of a tr///, tr[][],
5499 y/// or y[][] construct.
5501 =item '%s' trapped by operation mask
5503 (F) You tried to use an operator from a Safe compartment in which it's
5504 disallowed. See L<Safe>.
5506 =item truncate not implemented
5508 (F) Your machine doesn't implement a file truncation mechanism that
5509 Configure knows about.
5511 =item Type of arg %d to &CORE::%s must be %s
5513 (F) The subroutine in question in the CORE package requires its argument
5514 to be a hard reference to data of the specified type. Overloading is
5515 ignored, so a reference to an object that is not the specified type, but
5516 nonetheless has overloading to handle it, will still not be accepted.
5518 =item Type of arg %d to %s must be %s (not %s)
5520 (F) This function requires the argument in that position to be of a
5521 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
5522 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
5523 {EXPR} forms as an explicit dereference. See L<perlref>.
5525 =item Type of argument to %s must be unblessed hashref or arrayref
5527 (F) You called C<keys>, C<values> or C<each> with a scalar argument that
5528 was not a reference to an unblessed hash or array.
5530 =item umask not implemented
5532 (F) Your machine doesn't implement the umask function and you tried to
5533 use it to restrict permissions for yourself (EXPR & 0700).
5535 =item Unbalanced context: %d more PUSHes than POPs
5537 (S internal) The exit code detected an internal inconsistency in how
5538 many execution contexts were entered and left.
5540 =item Unbalanced saves: %d more saves than restores
5542 (S internal) The exit code detected an internal inconsistency in how
5543 many values were temporarily localized.
5545 =item Unbalanced scopes: %d more ENTERs than LEAVEs
5547 (S internal) The exit code detected an internal inconsistency in how
5548 many blocks were entered and left.
5550 =item Unbalanced string table refcount: (%d) for "%s"
5552 (S internal) On exit, Perl found some strings remaining in the shared
5553 string table used for copy on write and for hash keys. The entries
5554 should have been freed, so this indicates a bug somewhere.
5556 =item Unbalanced tmps: %d more allocs than frees
5558 (S internal) The exit code detected an internal inconsistency in how
5559 many mortal scalars were allocated and freed.
5561 =item Undefined format "%s" called
5563 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5564 another package? See L<perlform>.
5566 =item Undefined sort subroutine "%s" called
5568 (F) The sort comparison routine specified doesn't seem to exist.
5569 Perhaps it's in a different package? See L<perlfunc/sort>.
5571 =item Undefined subroutine &%s called
5573 (F) The subroutine indicated hasn't been defined, or if it was, it has
5574 since been undefined.
5576 =item Undefined subroutine called
5578 (F) The anonymous subroutine you're trying to call hasn't been defined,
5579 or if it was, it has since been undefined.
5581 =item Undefined subroutine in sort
5583 (F) The sort comparison routine specified is declared but doesn't seem
5584 to have been defined yet. See L<perlfunc/sort>.
5586 =item Undefined top format "%s" called
5588 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5589 another package? See L<perlform>.
5591 =item Undefined value assigned to typeglob
5593 (W misc) An undefined value was assigned to a typeglob, a la
5594 C<*foo = undef>. This does nothing. It's possible that you really mean
5597 =item %s: Undefined variable
5599 (A) You've accidentally run your script through B<csh> instead of Perl.
5600 Check the #! line, or manually feed your script into Perl yourself.
5602 =item unexec of %s into %s failed!
5604 (F) The unexec() routine failed for some reason. See your local FSF
5605 representative, who probably put it there in the first place.
5607 =item Unexpected binary operator '%c' with no preceding operand in regex;
5608 marked by S<<-- HERE> in m/%s/
5610 (F) You had something like this:
5614 where the C<"|"> is a binary operator with an operand on the right, but
5615 no operand on the left.
5617 =item Unexpected character in regex; marked by S<<-- HERE> in m/%s/
5619 (F) You had something like this:
5623 Within C<(?[ ])>, no literal characters are allowed unless they are
5624 within an inner pair of square brackets, like
5628 Another possibility is that you forgot a backslash. Perl isn't smart
5629 enough to figure out what you really meant.
5631 =item Unexpected constant lvalue entersub entry via type/targ %d:%d
5633 (P) When compiling a subroutine call in lvalue context, Perl failed an
5634 internal consistency check. It encountered a malformed op tree.
5636 =item Unexpected exit %u
5638 (S) exit() was called or the script otherwise finished gracefully when
5639 C<PERL_EXIT_WARN> was set in C<PL_exit_flags>.
5641 =item Unexpected exit failure %d
5643 (S) An uncaught die() was called when C<PERL_EXIT_WARN> was set in
5646 =item Unexpected ')' in regex; marked by S<<-- HERE> in m/%s/
5648 (F) You had something like this:
5650 (?[ ( \p{Digit} + ) ])
5652 The C<")"> is out-of-place. Something apparently was supposed to
5653 be combined with the digits, or the C<"+"> shouldn't be there, or
5654 something like that. Perl can't figure out what was intended.
5656 =item Unexpected '(' with no preceding operator in regex; marked by
5657 S<<-- HERE> in m/%s/
5659 (F) You had something like this:
5661 (?[ \p{Digit} ( \p{Lao} + \p{Thai} ) ])
5663 There should be an operator before the C<"(">, as there's
5664 no indication as to how the digits are to be combined
5665 with the characters in the Lao and Thai scripts.
5667 =item Unicode non-character U+%X is illegal for open interchange
5669 (S nonchar) Certain codepoints, such as U+FFFE and U+FFFF, are
5670 defined by the Unicode standard to be non-characters. Those are
5671 legal codepoints, but are reserved for internal use; so, applications
5672 shouldn't attempt to exchange them. If you know what you are doing
5673 you can turn off this warning by C<no warnings 'nonchar';>.
5675 =item Unicode surrogate U+%X is illegal in UTF-8
5677 (S surrogate) You had a UTF-16 surrogate in a context where they are
5678 not considered acceptable. These code points, between U+D800 and
5679 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
5680 internally allows all unsigned integer code points (up to the size limit
5681 available on your platform), including surrogates. But these can cause
5682 problems when being input or output, which is likely where this message
5683 came from. If you really really know what you are doing you can turn
5684 off this warning by C<no warnings 'surrogate';>.
5686 =item Unknown charname '%s'
5688 (F) The name you used inside C<\N{}> is unknown to Perl. Check the
5689 spelling. You can say C<use charnames ":loose"> to not have to be
5690 so precise about spaces, hyphens, and capitalization on standard Unicode
5691 names. (Any custom aliases that have been created must be specified
5692 exactly, regardless of whether C<:loose> is used or not.) This error may
5693 also happen if the C<\N{}> is not in the scope of the corresponding
5694 C<S<use charnames>>.
5698 (P) Perl was about to print an error message in C<$@>, but the C<$@> variable
5699 did not exist, even after an attempt to create it.
5701 =item Unknown open() mode '%s'
5703 (F) The second argument of 3-argument open() is not among the list
5704 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
5705 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
5707 =item Unknown PerlIO layer "%s"
5709 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
5710 system. (Layers take care of transforming data between external and
5711 internal representations.) Note that some layers, such as C<mmap>,
5712 are not supported in all environments. If your program didn't
5713 explicitly request the failing operation, it may be the result of the
5714 value of the environment variable PERLIO.
5716 =item Unknown process %x sent message to prime_env_iter: %s
5718 (P) An error peculiar to VMS. Perl was reading values for %ENV before
5719 iterating over it, and someone else stuck a message in the stream of
5720 data Perl expected. Someone's very confused, or perhaps trying to
5721 subvert Perl's population of %ENV for nefarious purposes.
5723 =item Unknown regex modifier "%s"
5725 (F) Alphanumerics immediately following the closing delimiter
5726 of a regular expression pattern are interpreted by Perl as modifier
5727 flags for the regex. One of the ones you specified is invalid. One way
5728 this can happen is if you didn't put in white space between the end of
5729 the regex and a following alphanumeric operator:
5731 if ($a =~ /foo/and $bar == 3) { ... }
5733 The C<"a"> is a valid modifier flag, but the C<"n"> is not, and raises
5734 this error. Likely what was meant instead was:
5736 if ($a =~ /foo/ and $bar == 3) { ... }
5738 =item Unknown "re" subpragma '%s' (known ones are: %s)
5740 (W) You tried to use an unknown subpragma of the "re" pragma.
5742 =item Unknown switch condition (?(...)) in regex; marked by S<<-- HERE> in
5745 (F) The condition part of a (?(condition)if-clause|else-clause) construct
5746 is not known. The condition must be one of the following:
5748 (1) (2) ... true if 1st, 2nd, etc., capture matched
5749 (<NAME>) ('NAME') true if named capture matched
5750 (?=...) (?<=...) true if subpattern matches
5751 (?!...) (?<!...) true if subpattern fails to match
5752 (?{ CODE }) true if code returns a true value
5753 (R) true if evaluating inside recursion
5754 (R1) (R2) ... true if directly inside capture group 1, 2, etc.
5755 (R&NAME) true if directly inside named capture
5756 (DEFINE) always false; for defining named subpatterns
5758 The <-- HERE shows whereabouts in the regular expression the problem was
5759 discovered. See L<perlre>.
5761 =item Unknown Unicode option letter '%c'
5763 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5764 of the C<-C> switch for the list of known options.
5766 =item Unknown Unicode option value %d
5768 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5769 of the C<-C> switch for the list of known options.
5771 =item Unknown verb pattern '%s' in regex; marked by S<<-- HERE> in m/%s/
5773 (F) You either made a typo or have incorrectly put a C<*> quantifier
5774 after an open brace in your pattern. Check the pattern and review
5775 L<perlre> for details on legal verb patterns.
5777 =item Unknown warnings category '%s'
5779 (F) An error issued by the C<warnings> pragma. You specified a warnings
5780 category that is unknown to perl at this point.
5782 Note that if you want to enable a warnings category registered by a
5783 module (e.g. C<use warnings 'File::Find'>), you must have loaded this
5786 =item Unmatched '[' in POSIX class in regex; marked by S<<-- HERE> in m/%s/
5788 (F) You had something like this:
5792 That should be written:
5796 =item Unmatched '%c' in POSIX class in regex; marked by S<<-- HERE> in
5799 (F) You had something like this:
5803 There should be a second C<":">, like this:
5807 =item Unmatched [ in regex; marked by S<<-- HERE> in m/%s/
5809 (F) The brackets around a character class must match. If you wish to
5810 include a closing bracket in a character class, backslash it or put it
5811 first. The S<<-- HERE> shows whereabouts in the regular expression the
5812 problem was discovered. See L<perlre>.
5814 =item Unmatched ( in regex; marked by S<<-- HERE> in m/%s/
5816 =item Unmatched ) in regex; marked by S<<-- HERE> in m/%s/
5818 (F) Unbackslashed parentheses must always be balanced in regular
5819 expressions. If you're a vi user, the % key is valuable for finding
5820 the matching parenthesis. The S<<-- HERE> shows whereabouts in the
5821 regular expression the problem was discovered. See L<perlre>.
5823 =item Unmatched right %s bracket
5825 (F) The lexer counted more closing curly or square brackets than opening
5826 ones, so you're probably missing a matching opening bracket. As a
5827 general rule, you'll find the missing one (so to speak) near the place
5828 you were last editing.
5830 =item Unquoted string "%s" may clash with future reserved word
5832 (W reserved) You used a bareword that might someday be claimed as a
5833 reserved word. It's best to put such a word in quotes, or capitalize it
5834 somehow, or insert an underbar into it. You might also declare it as a
5837 =item Unrecognized character %s; marked by S<<-- HERE> after %s near column
5840 (F) The Perl parser has no idea what to do with the specified character
5841 in your Perl script (or eval) near the specified column. Perhaps you tried
5842 to run a compressed script, a binary program, or a directory as a Perl program.
5844 =item Unrecognized escape \%c in character class in regex; marked by
5845 S<<-- HERE> in m/%s/
5847 (F) You used a backslash-character combination which is not
5848 recognized by Perl inside character classes. This is a fatal
5849 error when the character class is used within C<(?[ ])>.
5851 =item Unrecognized escape \%c in character class passed through in regex;
5852 marked by S<<-- HERE> in m/%s/
5854 (W regexp) You used a backslash-character combination which is not
5855 recognized by Perl inside character classes. The character was
5856 understood literally, but this may change in a future version of Perl.
5857 The S<<-- HERE> shows whereabouts in the regular expression the
5858 escape was discovered.
5860 =item Unrecognized escape \%c passed through
5862 (W misc) You used a backslash-character combination which is not
5863 recognized by Perl. The character was understood literally, but this may
5864 change in a future version of Perl.
5866 =item Unrecognized escape \%s passed through in regex; marked by
5867 S<<-- HERE> in m/%s/
5869 (W regexp) You used a backslash-character combination which is not
5870 recognized by Perl. The character(s) were understood literally, but
5871 this may change in a future version of Perl. The S<<-- HERE> shows
5872 whereabouts in the regular expression the escape was discovered.
5874 =item Unrecognized signal name "%s"
5876 (F) You specified a signal name to the kill() function that was not
5877 recognized. Say C<kill -l> in your shell to see the valid signal names
5880 =item Unrecognized switch: -%s (-h will show valid options)
5882 (F) You specified an illegal option to Perl. Don't do that. (If you
5883 think you didn't do that, check the #! line to see if it's supplying the
5884 bad switch on your behalf.)
5886 =item unshift on reference is experimental
5888 (S experimental::autoderef) C<unshift> with a scalar argument
5889 is experimental and may change or be removed in a future
5890 Perl version. If you want to take the risk of using this
5891 feature, simply disable this warning:
5893 no warnings "experimental::autoderef";
5895 =item Unsuccessful %s on filename containing newline
5897 (W newline) A file operation was attempted on a filename, and that
5898 operation failed, PROBABLY because the filename contained a newline,
5899 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
5901 =item Unsupported directory function "%s" called
5903 (F) Your machine doesn't support opendir() and readdir().
5905 =item Unsupported function %s
5907 (F) This machine doesn't implement the indicated function, apparently.
5908 At least, Configure doesn't think so.
5910 =item Unsupported function fork
5912 (F) Your version of executable does not support forking.
5914 Note that under some systems, like OS/2, there may be different flavors
5915 of Perl executables, some of which may support fork, some not. Try
5916 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
5918 =item Unsupported script encoding %s
5920 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
5921 declares it to be in a Unicode encoding that Perl cannot read.
5923 =item Unsupported socket function "%s" called
5925 (F) Your machine doesn't support the Berkeley socket mechanism, or at
5926 least that's what Configure thought.
5928 =item Unterminated attribute list
5930 (F) The lexer found something other than a simple identifier at the
5931 start of an attribute, and it wasn't a semicolon or the start of a
5932 block. Perhaps you terminated the parameter list of the previous
5933 attribute too soon. See L<attributes>.
5935 =item Unterminated attribute parameter in attribute list
5937 (F) The lexer saw an opening (left) parenthesis character while parsing
5938 an attribute list, but the matching closing (right) parenthesis
5939 character was not found. You may need to add (or remove) a backslash
5940 character to get your parentheses to balance. See L<attributes>.
5942 =item Unterminated compressed integer
5944 (F) An argument to unpack("w",...) was incompatible with the BER
5945 compressed integer format and could not be converted to an integer.
5946 See L<perlfunc/pack>.
5948 =item Unterminated delimiter for here document
5950 (F) This message occurs when a here document label has an initial
5951 quotation mark but the final quotation mark is missing. Perhaps
5960 =item Unterminated \g... pattern in regex; marked by S<<-- HERE> in m/%s/
5962 =item Unterminated \g{...} pattern in regex; marked by S<<-- HERE> in m/%s/
5964 (F) In a regular expression, you had a C<\g> that wasn't followed by a
5965 proper group reference. In the case of C<\g{>, the closing brace is
5966 missing; otherwise the C<\g> must be followed by an integer. Fix the
5969 =item Unterminated <> operator
5971 (F) The lexer saw a left angle bracket in a place where it was expecting
5972 a term, so it's looking for the corresponding right angle bracket, and
5973 not finding it. Chances are you left some needed parentheses out
5974 earlier in the line, and you really meant a "less than".
5976 =item Unterminated verb pattern argument in regex; marked by S<<-- HERE> in
5979 (F) You used a pattern of the form C<(*VERB:ARG)> but did not terminate
5980 the pattern with a C<)>. Fix the pattern and retry.
5982 =item Unterminated verb pattern in regex; marked by S<<-- HERE> in m/%s/
5984 (F) You used a pattern of the form C<(*VERB)> but did not terminate
5985 the pattern with a C<)>. Fix the pattern and retry.
5987 =item untie attempted while %d inner references still exist
5989 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
5990 still valid when C<untie> was called.
5992 =item Usage: POSIX::%s(%s)
5994 (F) You called a POSIX function with incorrect arguments.
5995 See L<POSIX/FUNCTIONS> for more information.
5997 =item Usage: Win32::%s(%s)
5999 (F) You called a Win32 function with incorrect arguments.
6000 See L<Win32> for more information.
6002 =item $[ used in %s (did you mean $] ?)
6004 (W syntax) You used C<$[> in a comparison, such as:
6010 You probably meant to use C<$]> instead. C<$[> is the base for indexing
6011 arrays. C<$]> is the Perl version number in decimal.
6013 =item Useless assignment to a temporary
6015 (W misc) You assigned to an lvalue subroutine, but what
6016 the subroutine returned was a temporary scalar about to
6017 be discarded, so the assignment had no effect.
6019 =item Useless (?-%s) - don't use /%s modifier in regex; marked by
6020 S<<-- HERE> in m/%s/
6022 (W regexp) You have used an internal modifier such as (?-o) that has no
6023 meaning unless removed from the entire regexp:
6025 if ($string =~ /(?-o)$pattern/o) { ... }
6029 if ($string =~ /$pattern/) { ... }
6031 The <-- HERE shows whereabouts in the regular expression the problem was
6032 discovered. See L<perlre>.
6034 =item Useless localization of %s
6036 (W syntax) The localization of lvalues such as C<local($x=10)> is legal,
6037 but in fact the local() currently has no effect. This may change at
6038 some point in the future, but in the meantime such code is discouraged.
6040 =item Useless (?%s) - use /%s modifier in regex; marked by S<<-- HERE> in
6043 (W regexp) You have used an internal modifier such as (?o) that has no
6044 meaning unless applied to the entire regexp:
6046 if ($string =~ /(?o)$pattern/) { ... }
6050 if ($string =~ /$pattern/o) { ... }
6052 The <-- HERE shows whereabouts in the regular expression the problem was
6053 discovered. See L<perlre>.
6055 =item Useless use of /d modifier in transliteration operator
6057 (W misc) You have used the /d modifier where the searchlist has the
6058 same length as the replacelist. See L<perlop> for more information
6059 about the /d modifier.
6061 =item Useless use of '\'; doesn't escape metacharacter '%c'
6063 (D deprecated) You wrote a regular expression pattern something like
6069 s[foo\[a-z\]bar][baz]
6071 The interior braces, square brackets, and parentheses are treated as
6072 metacharacters even though they are backslashed; instead write:
6079 The backslashes have no effect when a regular expression pattern is
6080 delimited by C<{}>, C<[]>, or C<()>, which ordinarily are
6081 metacharacters, and the delimiters are also used, paired, within the
6082 interior of the pattern. It is planned that a future Perl release will
6083 change the meaning of constructs like these so that the backslashes
6084 will have an effect, so remove them from your code.
6086 =item Useless use of \E
6088 (W misc) You have a \E in a double-quotish string without a C<\U>,
6089 C<\L> or C<\Q> preceding it.
6091 =item Useless use of greediness modifier '%c' in regex; marked by S<<-- HERE> in m/%s/
6093 (W regexp) You specified something like these:
6098 The C<"?"> and C<"+"> don't have any effect, as they modify whether to
6099 match more or fewer when there is a choice, and by specifying to match
6100 exactly a given numer, there is no room left for a choice.
6102 =item Useless use of %s in void context
6104 (W void) You did something without a side effect in a context that does
6105 nothing with the return value, such as a statement that doesn't return a
6106 value from a block, or the left side of a scalar comma operator. Very
6107 often this points not to stupidity on your part, but a failure of Perl
6108 to parse your program the way you thought it would. For example, you'd
6109 get this if you mixed up your C precedence with Python precedence and
6114 when you meant to say
6116 ($one, $two) = (1, 2);
6118 Another common error is to use ordinary parentheses to construct a list
6119 reference when you should be using square or curly brackets, for
6124 when you should have said
6128 The square brackets explicitly turn a list value into a scalar value,
6129 while parentheses do not. So when a parenthesized list is evaluated in
6130 a scalar context, the comma is treated like C's comma operator, which
6131 throws away the left argument, which is not what you want. See
6132 L<perlref> for more on this.
6134 This warning will not be issued for numerical constants equal to 0 or 1
6135 since they are often used in statements like
6137 1 while sub_with_side_effects();
6139 String constants that would normally evaluate to 0 or 1 are warned
6142 =item Useless use of (?-p) in regex; marked by S<<-- HERE> in m/%s/
6144 (W regexp) The C<p> modifier cannot be turned off once set. Trying to do
6147 =item Useless use of "re" pragma
6149 (W) You did C<use re;> without any arguments. That isn't very useful.
6151 =item Useless use of sort in scalar context
6153 (W void) You used sort in scalar context, as in :
6157 This is not very useful, and perl currently optimizes this away.
6159 =item Useless use of %s with no values
6161 (W syntax) You used the push() or unshift() function with no arguments
6162 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
6163 usually have any effect on the array, so is completely useless. It's
6164 possible in principle that push(@tied_array) could have some effect
6165 if the array is tied to a class which implements a PUSH method. If so,
6166 you can write it as C<push(@tied_array,())> to avoid this warning.
6168 =item "use" not allowed in expression
6170 (F) The "use" keyword is recognized and executed at compile time, and
6171 returns no useful value. See L<perlmod>.
6173 =item Use of assignment to $[ is deprecated
6175 (D deprecated) The C<$[> variable (index of the first element in an array)
6176 is deprecated. See L<perlvar/"$[">.
6178 =item Use of bare << to mean <<"" is deprecated
6180 (D deprecated) You are now encouraged to use the explicitly quoted
6181 form if you wish to use an empty line as the terminator of the here-document.
6183 =item Use of chdir('') or chdir(undef) as chdir() deprecated
6185 (D deprecated) chdir() with no arguments is documented to change to
6186 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
6187 behavior, but that has been deprecated. In future versions they
6190 Be careful to check that what you pass to chdir() is defined and not
6191 blank, else you might find yourself in your home directory.
6193 =item Use of /c modifier is meaningless in s///
6195 (W regexp) You used the /c modifier in a substitution. The /c
6196 modifier is not presently meaningful in substitutions.
6198 =item Use of /c modifier is meaningless without /g
6200 (W regexp) You used the /c modifier with a regex operand, but didn't
6201 use the /g modifier. Currently, /c is meaningful only when /g is
6202 used. (This may change in the future.)
6204 =item Use of comma-less variable list is deprecated
6206 (D deprecated) The values you give to a format should be
6207 separated by commas, not just aligned on a line.
6209 =item Use of each() on hash after insertion without resetting hash iterator results in undefined behavior
6211 (S internal) The behavior of C<each()> after insertion is undefined;
6212 it may skip items, or visit items more than once. Consider using
6213 C<keys()> instead of C<each()>.
6215 =item Use of := for an empty attribute list is not allowed
6217 (F) The construction C<my $x := 42> used to parse as equivalent to
6218 C<my $x : = 42> (applying an empty attribute list to C<$x>).
6219 This construct was deprecated in 5.12.0, and has now been made a syntax
6220 error, so C<:=> can be reclaimed as a new operator in the future.
6222 If you need an empty attribute list, for example in a code generator, add
6223 a space before the C<=>.
6225 =item Use of freed value in iteration
6227 (F) Perhaps you modified the iterated array within the loop?
6228 This error is typically caused by code like the following:
6231 @a = () for (1,2,@a);
6233 You are not supposed to modify arrays while they are being iterated over.
6234 For speed and efficiency reasons, Perl internally does not do full
6235 reference-counting of iterated items, hence deleting such an item in the
6236 middle of an iteration causes Perl to see a freed value.
6238 =item Use of *glob{FILEHANDLE} is deprecated
6240 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
6241 to access the filehandle slot within a typeglob.
6243 =item Use of /g modifier is meaningless in split
6245 (W regexp) You used the /g modifier on the pattern for a C<split>
6246 operator. Since C<split> always tries to match the pattern
6247 repeatedly, the C</g> has no effect.
6249 =item Use of "goto" to jump into a construct is deprecated
6251 (D deprecated) Using C<goto> to jump from an outer scope into an inner
6252 scope is deprecated and should be avoided.
6254 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
6256 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD>
6257 subroutines are looked up as methods (using the C<@ISA> hierarchy)
6258 even when the subroutines to be autoloaded were called as plain
6259 functions (e.g. C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or
6260 C<< $obj->bar() >>).
6262 This bug will be rectified in future by using method lookup only for
6263 methods' C<AUTOLOAD>s. However, there is a significant base of existing
6264 code that may be using the old behavior. So, as an interim step, Perl
6265 currently issues an optional warning when non-methods use inherited
6268 The simple rule is: Inheritance will not work when autoloading
6269 non-methods. The simple fix for old code is: In any module that used
6270 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
6271 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
6274 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
6275 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
6276 C<use AutoLoader 'AUTOLOAD';>.
6278 =item Use of %s in printf format not supported
6280 (F) You attempted to use a feature of printf that is accessible from
6281 only C. This usually means there's a better way to do it in Perl.
6283 =item Use of %s is deprecated
6285 (D deprecated) The construct indicated is no longer recommended for use,
6286 generally because there's a better way to do it, and also because the
6287 old way has bad side effects.
6289 =item Use of literal control characters in variable names is deprecated
6291 (D deprecated) Using literal control characters in the source to refer
6292 to the ^FOO variables, like C<$^X> and C<${^GLOBAL_PHASE}> is now
6293 deprecated. This only affects code like C<$\cT>, where \cT is a control in
6294 the source code: C<${"\cT"}> and C<$^T> remain valid.
6296 =item Use of -l on filehandle%s
6298 (W io) A filehandle represents an opened file, and when you opened the file
6299 it already went past any symlink you are presumably trying to look for.
6300 The operation returned C<undef>. Use a filename instead.
6302 =item Use of my $_ is experimental
6304 (S experimental::lexical_topic) Lexical $_ is an experimental feature and
6305 its behavior may change or even be removed in any future release of perl.
6306 See the explanation under L<perlvar/$_>.
6308 =item Use of %s on a handle without * is deprecated
6310 (D deprecated) You used C<tie>, C<tied> or C<untie> on a scalar but that scalar
6311 happens to hold a typeglob, which means its filehandle will be tied. If
6312 you mean to tie a handle, use an explicit * as in C<tie *$handle>.
6314 This was a long-standing bug that was removed in Perl 5.16, as there was
6315 no way to tie the scalar itself when it held a typeglob, and no way to
6316 untie a scalar that had had a typeglob assigned to it. If you see this
6317 message, you must be using an older version.
6319 =item Use of ?PATTERN? without explicit operator is deprecated
6321 (D deprecated) You have written something like C<?\w?>, for a regular
6322 expression that matches only once. Starting this term directly with
6323 the question mark delimiter is now deprecated, so that the question mark
6324 will be available for use in new operators in the future. Write C<m?\w?>
6325 instead, explicitly using the C<m> operator: the question mark delimiter
6326 still invokes match-once behaviour.
6328 =item Use of reference "%s" as array index
6330 (W misc) You tried to use a reference as an array index; this probably
6331 isn't what you mean, because references in numerical context tend
6332 to be huge numbers, and so usually indicates programmer error.
6334 If you really do mean it, explicitly numify your reference, like so:
6335 C<$array[0+$ref]>. This warning is not given for overloaded objects,
6336 however, because you can overload the numification and stringification
6337 operators and then you presumably know what you are doing.
6339 =item Use of state $_ is experimental
6341 (S experimental::lexical_topic) Lexical $_ is an experimental feature and
6342 its behavior may change or even be removed in any future release of perl.
6343 See the explanation under L<perlvar/$_>.
6345 =item Use of tainted arguments in %s is deprecated
6347 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
6348 arguments and at least one of them is tainted. This used to be allowed
6349 but will become a fatal error in a future version of perl. Untaint your
6350 arguments. See L<perlsec>.
6352 =item Use of uninitialized value%s
6354 (W uninitialized) An undefined value was used as if it were already
6355 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
6356 To suppress this warning assign a defined value to your variables.
6358 To help you figure out what was undefined, perl will try to tell you
6359 the name of the variable (if any) that was undefined. In some cases
6360 it cannot do this, so it also tells you what operation you used the
6361 undefined value in. Note, however, that perl optimizes your program
6362 and the operation displayed in the warning may not necessarily appear
6363 literally in your program. For example, C<"that $foo"> is usually
6364 optimized into C<"that " . $foo>, and the warning will refer to the
6365 C<concatenation (.)> operator, even though there is no C<.> in
6368 =item Use \x{...} for more than two hex characters in regex; marked by
6369 S<<-- HERE> in m/%s/
6371 (F) In a regular expression, you said something like
6375 Perl isn't sure if you meant this
6379 or if you meant this
6381 (?[ [ \x{BE} E F ] ])
6383 You need to add either braces or blanks to disambiguate.
6385 =item Using a hash as a reference is deprecated
6387 (D deprecated) You tried to use a hash as a reference, as in
6388 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
6389 used to allow this syntax, but shouldn't have. It is now
6390 deprecated, and will be removed in a future version.
6392 =item Using an array as a reference is deprecated
6394 (D deprecated) You tried to use an array as a reference, as in
6395 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
6396 allow this syntax, but shouldn't have. It is now deprecated,
6397 and will be removed in a future version.
6399 =item Using just the first character returned by \N{} in character class in
6400 regex; marked by S<<-- HERE> in m/%s/
6402 (W regexp) A charnames handler may return a sequence of more than one
6403 character. Currently all but the first one are discarded when used in
6404 a regular expression pattern bracketed character class.
6406 =item Using !~ with %s doesn't make sense
6408 (F) Using the C<!~> operator with C<s///r>, C<tr///r> or C<y///r> is
6409 currently reserved for future use, as the exact behaviour has not
6410 been decided. (Simply returning the boolean opposite of the
6411 modified string is usually not particularly useful.)
6413 =item UTF-16 surrogate U+%X
6415 (S surrogate) You had a UTF-16 surrogate in a context where they are
6416 not considered acceptable. These code points, between U+D800 and
6417 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
6418 internally allows all unsigned integer code points (up to the size limit
6419 available on your platform), including surrogates. But these can cause
6420 problems when being input or output, which is likely where this message
6421 came from. If you really really know what you are doing you can turn
6422 off this warning by C<no warnings 'surrogate';>.
6424 =item Value of %s can be "0"; test with defined()
6426 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
6427 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
6428 can return a value of "0"; that would make the conditional expression
6429 false, which is probably not what you intended. When using these
6430 constructs in conditional expressions, test their values with the
6431 C<defined> operator.
6433 =item Value of CLI symbol "%s" too long
6435 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
6436 %ENV element from a CLI symbol table, and found a resultant string
6437 longer than 1024 characters. The return value has been truncated to
6440 =item values on reference is experimental
6442 (S experimental::autoderef) C<values> with a scalar argument
6443 is experimental and may change or be removed in a future
6444 Perl version. If you want to take the risk of using this
6445 feature, simply disable this warning:
6447 no warnings "experimental::autoderef";
6449 =item Variable "%s" is not available
6451 (W closure) During compilation, an inner named subroutine or eval is
6452 attempting to capture an outer lexical that is not currently available.
6453 This can happen for one of two reasons. First, the outer lexical may be
6454 declared in an outer anonymous subroutine that has not yet been created.
6455 (Remember that named subs are created at compile time, while anonymous
6456 subs are created at run-time.) For example,
6458 sub { my $a; sub f { $a } }
6460 At the time that f is created, it can't capture the current value of $a,
6461 since the anonymous subroutine hasn't been created yet. Conversely,
6462 the following won't give a warning since the anonymous subroutine has by
6463 now been created and is live:
6465 sub { my $a; eval 'sub f { $a }' }->();
6467 The second situation is caused by an eval accessing a variable that has
6468 gone out of scope, for example,
6476 Here, when the '$a' in the eval is being compiled, f() is not currently being
6477 executed, so its $a is not available for capture.
6479 =item Variable "%s" is not imported%s
6481 (S misc) With "use strict" in effect, you referred to a global variable
6482 that you apparently thought was imported from another module, because
6483 something else of the same name (usually a subroutine) is exported by
6484 that module. It usually means you put the wrong funny character on the
6485 front of your variable.
6487 =item Variable length lookbehind not implemented in regex m/%s/
6489 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
6490 known at compile time. See L<perlre>.
6492 =item "%s" variable %s masks earlier declaration in same %s
6494 (W misc) A "my", "our" or "state" variable has been redeclared in the
6495 current scope or statement, effectively eliminating all access to the
6496 previous instance. This is almost always a typographical error. Note
6497 that the earlier variable will still exist until the end of the scope
6498 or until all closure references to it are destroyed.
6500 =item Variable syntax
6502 (A) You've accidentally run your script through B<csh> instead
6503 of Perl. Check the #! line, or manually feed your script into
6506 =item Variable "%s" will not stay shared
6508 (W closure) An inner (nested) I<named> subroutine is referencing a
6509 lexical variable defined in an outer named subroutine.
6511 When the inner subroutine is called, it will see the value of
6512 the outer subroutine's variable as it was before and during the *first*
6513 call to the outer subroutine; in this case, after the first call to the
6514 outer subroutine is complete, the inner and outer subroutines will no
6515 longer share a common value for the variable. In other words, the
6516 variable will no longer be shared.
6518 This problem can usually be solved by making the inner subroutine
6519 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
6520 reference variables in outer subroutines are created, they
6521 are automatically rebound to the current values of such variables.
6523 =item vector argument not supported with alpha versions
6525 (S printf) The %vd (s)printf format does not support version objects
6528 =item Verb pattern '%s' has a mandatory argument in regex; marked by
6529 S<<-- HERE> in m/%s/
6531 (F) You used a verb pattern that requires an argument. Supply an
6532 argument or check that you are using the right verb.
6534 =item Verb pattern '%s' may not have an argument in regex; marked by
6535 S<<-- HERE> in m/%s/
6537 (F) You used a verb pattern that is not allowed an argument. Remove the
6538 argument or check that you are using the right verb.
6540 =item Version number must be a constant number
6542 (P) The attempt to translate a C<use Module n.n LIST> statement into
6543 its equivalent C<BEGIN> block found an internal inconsistency with
6546 =item Version string '%s' contains invalid data; ignoring: '%s'
6548 (W misc) The version string contains invalid characters at the end, which
6551 =item Warning: something's wrong
6553 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
6554 you called it with no args and C<$@> was empty.
6556 =item Warning: unable to close filehandle %s properly
6558 (S) The implicit close() done by an open() got an error indication on
6559 the close(). This usually indicates your file system ran out of disk
6562 =item Warning: Use of "%s" without parentheses is ambiguous
6564 (S ambiguous) You wrote a unary operator followed by something that
6565 looks like a binary operator that could also have been interpreted as a
6566 term or unary operator. For instance, if you know that the rand
6567 function has a default argument of 1.0, and you write
6571 you may THINK you wrote the same thing as
6575 but in actual fact, you got
6579 So put in parentheses to say what you really mean.
6581 =item when is experimental
6583 (S experimental::smartmatch) C<when> depends on smartmatch, which is
6584 experimental. Additionally, it has several special cases that may
6585 not be immediately obvious, and their behavior may change or
6586 even be removed in any future release of perl. See the explanation
6587 under L<perlsyn/Experimental Details on given and when>.
6589 =item Wide character in %s
6591 (S utf8) Perl met a wide character (>255) when it wasn't expecting
6592 one. This warning is by default on for I/O (like print). The easiest
6593 way to quiet this warning is simply to add the C<:utf8> layer to the
6594 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
6595 warning is to add C<no warnings 'utf8';> but that is often closer to
6596 cheating. In general, you are supposed to explicitly mark the
6597 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
6599 =item Within []-length '%c' not allowed
6601 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]>
6602 only if C<TEMPLATE> always matches the same amount of packed bytes that
6603 can be determined from the template alone. This is not possible if
6604 it contains any of the codes @, /, U, u, w or a *-length. Redesign
6607 =item write() on closed filehandle %s
6609 (W closed) The filehandle you're writing to got itself closed sometime
6610 before now. Check your control flow.
6612 =item %s "\x%X" does not map to Unicode
6614 (S utf8) When reading in different encodings, Perl tries to
6615 map everything into Unicode characters. The bytes you read
6616 in are not legal in this encoding. For example
6618 utf8 "\xE4" does not map to Unicode
6620 if you try to read in the a-diaereses Latin-1 as UTF-8.
6622 =item 'X' outside of string
6624 (F) You had a (un)pack template that specified a relative position before
6625 the beginning of the string being (un)packed. See L<perlfunc/pack>.
6627 =item 'x' outside of string in unpack
6629 (F) You had a pack template that specified a relative position after
6630 the end of the string being unpacked. See L<perlfunc/pack>.
6632 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
6634 (F) And you probably never will, because you probably don't have the
6635 sources to your kernel, and your vendor probably doesn't give a rip
6636 about what you want. Your best bet is to put a setuid C wrapper around
6639 =item You need to quote "%s"
6641 (W syntax) You assigned a bareword as a signal handler name.
6642 Unfortunately, you already have a subroutine of that name declared,
6643 which means that Perl 5 will try to call the subroutine when the
6644 assignment is executed, which is probably not what you want. (If it IS
6645 what you want, put an & in front.)
6647 =item Your random numbers are not that random
6649 (F) When trying to initialize the random seed for hashes, Perl could
6650 not get any randomness out of your system. This usually indicates
6651 Something Very Wrong.
6653 =item Zero length \N{} in regex; marked by S<<-- HERE> in m/%s/
6655 (F) Named Unicode character escapes C<(\N{...})> may return a zero-length
6656 sequence. Such an escape was used in an extended character class, i.e.
6657 C<(?[...])>, which is not permitted. Check that the correct escape has
6658 been used, and the correct charnames handler is in scope. The S<<-- HERE>
6659 shows whereabouts in the regular expression the problem was discovered.
6665 L<warnings>, L<perllexwarn>, L<diagnostics>.