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<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Severe warnings are always enabled, unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Allocation too large: %x
55 (X) You can't allocate more than 64K on an MS-DOS machine.
57 =item '%c' allowed only after types %s
59 (F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60 after certain types. See L<perlfunc/pack>.
62 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
64 (W ambiguous) A subroutine you have declared has the same name as a Perl
65 keyword, and you have used the name without qualification for calling
66 one or the other. Perl decided to call the builtin because the
67 subroutine is not imported.
69 To force interpretation as a subroutine call, either put an ampersand
70 before the subroutine name, or qualify the name with its package.
71 Alternatively, you can import the subroutine (or pretend that it's
72 imported with the C<use subs> pragma).
74 To silently interpret it as the Perl operator, use the C<CORE::> prefix
75 on the operator (e.g. C<CORE::log($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 %c resolved as operator %c
94 (S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
95 bitwise and, and multiplication) I<and> initial special characters
96 (denoting hashes, subroutines and typeglobs), and you said something
97 like C<*foo * foo> that might be interpreted as either of them. We
98 assumed you meant the infix operator, but please try to make it more
99 clear -- in the example given, you might write C<*foo * foo()> if you
100 really meant to multiply a glob by the result of calling a function.
102 =item Ambiguous use of %c{%s} resolved to %c%s
104 (W ambiguous) You wrote something like C<@{foo}>, which might be
105 asking for the variable C<@foo>, or it might be calling a function
106 named foo, and dereferencing it as an array reference. If you wanted
107 the variable, you can just write C<@foo>. If you wanted to call the
108 function, write C<@{foo()}> ... or you could just not have a variable
109 and a function with the same name, and save yourself a lot of trouble.
111 =item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
113 =item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
115 (W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
116 the name of a Perl keyword), which might be looking for element number
117 2 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
118 might have meant to pass an anonymous arrayref to the function named
119 foo, and then do a scalar deref on the value it returns. If you meant
120 that, write C<${foo([2])}>.
122 In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
123 to disambiguate between array subscripts and character classes.
124 C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
125 by the character class C<[2345]>. If an array subscript is what you
126 want, you can avoid the warning by changing C</${length[2345]}/> to the
127 unsightly C</${\$length[2345]}/>, by renaming your array to something
128 that does not coincide with a built-in keyword, or by simply turning
129 off warnings with C<no warnings 'ambiguous';>.
131 =item Ambiguous use of -%s resolved as -&%s()
133 (S ambiguous) You wrote something like C<-foo>, which might be the
134 string C<"-foo">, or a call to the function C<foo>, negated. If you meant
135 the string, just write C<"-foo">. If you meant the function call,
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]: $!";
159 =item Applying %s to %s will act on scalar(%s)
161 (W misc) The pattern match (C<//>), substitution (C<s///>), and
162 transliteration (C<tr///>) operators work on scalar values. If you apply
163 one of them to an array or a hash, it will convert the array or hash to
164 a scalar value (the length of an array, or the population info of a
165 hash) and then work on that scalar value. This is probably not what
166 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
169 =item Arg too short for msgsnd
171 (F) msgsnd() requires a string at least as long as sizeof(long).
173 =item %s argument is not a HASH or ARRAY element or a subroutine
175 (F) The argument to exists() must be a hash or array element or a
176 subroutine with an ampersand, such as:
182 =item %s argument is not a HASH or ARRAY element or slice
184 (F) The argument to delete() must be either a hash or array element,
190 or a hash or array slice, such as:
192 @foo[$bar, $baz, $xyzzy]
193 @{$ref->[12]}{"susie", "queue"}
195 =item %s argument is not a subroutine name
197 (F) The argument to exists() for C<exists &sub> must be a subroutine
198 name, and not a subroutine call. C<exists &sub()> will generate this
201 =item Argument "%s" isn't numeric%s
203 (W numeric) The indicated string was fed as an argument to an operator
204 that expected a numeric value instead. If you're fortunate the message
205 will identify which operator was so unfortunate.
207 =item Argument list not closed for PerlIO layer "%s"
209 (W layer) When pushing a layer with arguments onto the Perl I/O
210 system you forgot the ) that closes the argument list. (Layers
211 take care of transforming data between external and internal
212 representations.) Perl stopped parsing the layer list at this
213 point and did not attempt to push this layer. If your program
214 didn't explicitly request the failing operation, it may be the
215 result of the value of the environment variable PERLIO.
217 =item Array @%s missing the @ in argument %d of %s()
219 (D deprecated) Really old Perl let you omit the @ on array names in some
220 spots. This is now heavily deprecated.
222 =item A sequence of multiple spaces in a charnames alias definition is deprecated
224 (D) You defined a character name which had multiple space characters in
225 a row. Change them to single spaces. Usually these names are defined
226 in the C<:alias> import argument to C<use charnames>, but they could be
227 defined by a translator installed into C<$^H{charnames}>. See
228 L<charnames/CUSTOM ALIASES>.
230 =item assertion botched: %s
232 (X) The malloc package that comes with Perl had an internal failure.
234 =item Assertion failed: file "%s"
236 (X) A general assertion failed. The file in question must be examined.
238 =item Assigning non-zero to $[ is no longer possible
240 (F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
241 the special variable C<$[>, which is deprecated, is now a fixed zero value.
243 =item Assignment to both a list and a scalar
245 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
246 must either both be scalars or both be lists. Otherwise Perl won't
247 know which context to supply to the right side.
249 =item A thread exited while %d threads were running
251 (W threads)(S) When using threaded Perl, a thread (not necessarily
252 the main thread) exited while there were still other threads running.
253 Usually it's a good idea first to collect the return values of the
254 created threads by joining them, and only then to exit from the main
255 thread. See L<threads>.
257 =item Attempt to access disallowed key '%s' in a restricted hash
259 (F) The failing code has attempted to get or set a key which is not in
260 the current set of allowed keys of a restricted hash.
262 =item Attempt to bless into a reference
264 (F) The CLASSNAME argument to the bless() operator is expected to be
265 the name of the package to bless the resulting object into. You've
266 supplied instead a reference to something: perhaps you wrote
272 bless $self, ref($proto) || $proto;
274 If you actually want to bless into the stringified version
275 of the reference supplied, you need to stringify it yourself, for
278 bless $self, "$proto";
280 =item Attempt to clear deleted array
282 (S debugging) An array was assigned to when it was being freed.
283 Freed values are not supposed to be visible to Perl code. This
284 can also happen if XS code calls C<av_clear> from a custom magic
285 callback on the array.
287 =item Attempt to delete disallowed key '%s' from a restricted hash
289 (F) The failing code attempted to delete from a restricted hash a key
290 which is not in its key set.
292 =item Attempt to delete readonly key '%s' from a restricted hash
294 (F) The failing code attempted to delete a key whose value has been
295 declared readonly from a restricted hash.
297 =item Attempt to free non-arena SV: 0x%x
299 (S internal) All SV objects are supposed to be allocated from arenas
300 that will be garbage collected on exit. An SV was discovered to be
301 outside any of those arenas.
303 =item Attempt to free nonexistent shared string '%s'%s
305 (S internal) Perl maintains a reference-counted internal table of
306 strings to optimize the storage and access of hash keys and other
307 strings. This indicates someone tried to decrement the reference count
308 of a string that can no longer be found in the table.
310 =item Attempt to free temp prematurely: SV 0x%x
312 (S debugging) Mortalized values are supposed to be freed by the
313 free_tmps() routine. This indicates that something else is freeing the
314 SV before the free_tmps() routine gets a chance, which means that the
315 free_tmps() routine will be freeing an unreferenced scalar when it does
318 =item Attempt to free unreferenced glob pointers
320 (S internal) The reference counts got screwed up on symbol aliases.
322 =item Attempt to free unreferenced scalar: SV 0x%x
324 (S internal) Perl went to decrement the reference count of a scalar to
325 see if it would go to 0, and discovered that it had already gone to 0
326 earlier, and should have been freed, and in fact, probably was freed.
327 This could indicate that SvREFCNT_dec() was called too many times, or
328 that SvREFCNT_inc() was called too few times, or that the SV was
329 mortalized when it shouldn't have been, or that memory has been
332 =item Attempt to join self
334 (F) You tried to join a thread from within itself, which is an
335 impossible task. You may be joining the wrong thread, or you may need
336 to move the join() to some other thread.
338 =item Attempt to pack pointer to temporary value
340 (W pack) You tried to pass a temporary value (like the result of a
341 function, or a computed expression) to the "p" pack() template. This
342 means the result contains a pointer to a location that could become
343 invalid anytime, even before the end of the current statement. Use
344 literals or global values as arguments to the "p" pack() template to
347 =item Attempt to reload %s aborted.
349 (F) You tried to load a file with C<use> or C<require> that failed to
350 compile once already. Perl will not try to compile this file again
351 unless you delete its entry from %INC. See L<perlfunc/require> and
354 =item Attempt to set length of freed array
356 (W misc) You tried to set the length of an array which has
357 been freed. You can do this by storing a reference to the
358 scalar representing the last index of an array and later
359 assigning through that reference. For example
361 $r = do {my @a; \$#a};
364 =item Attempt to use reference as lvalue in substr
366 (W substr) You supplied a reference as the first argument to substr()
367 used as an lvalue, which is pretty strange. Perhaps you forgot to
368 dereference it first. See L<perlfunc/substr>.
370 =item Attribute "locked" is deprecated
372 (D deprecated) You have used the attributes pragma to modify the
373 "locked" attribute on a code reference. The :locked attribute is
374 obsolete, has had no effect since 5005 threads were removed, and
375 will be removed in a future release of Perl 5.
377 =item Attribute "unique" is deprecated
379 (D deprecated) You have used the attributes pragma to modify
380 the "unique" attribute on an array, hash or scalar reference.
381 The :unique attribute has had no effect since Perl 5.8.8, and
382 will be removed in a future release of Perl 5.
384 =item av_reify called on tied array
386 (S debugging) This indicates that something went wrong and Perl got I<very>
387 confused about C<@_> or C<@DB::args> being tied.
389 =item Bad arg length for %s, is %u, should be %d
391 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
392 or shmctl(). In C parlance, the correct sizes are, respectively,
393 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
394 S<sizeof(struct shmid_ds *)>.
396 =item Bad evalled substitution pattern
398 (F) You've used the C</e> switch to evaluate the replacement for a
399 substitution, but perl found a syntax error in the code to evaluate,
400 most likely an unexpected right brace '}'.
402 =item Bad filehandle: %s
404 (F) A symbol was passed to something wanting a filehandle, but the
405 symbol has no filehandle associated with it. Perhaps you didn't do an
406 open(), or did it in another package.
408 =item Bad free() ignored
410 (S malloc) An internal routine called free() on something that had never
411 been malloc()ed in the first place. Mandatory, but can be disabled by
412 setting environment variable C<PERL_BADFREE> to 0.
414 This message can be seen quite often with DB_File on systems with "hard"
415 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
416 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
420 (P) One of the internal hash routines was passed a null HV pointer.
422 =item Badly placed ()'s
424 (A) You've accidentally run your script through B<csh> instead
425 of Perl. Check the #! line, or manually feed your script into
428 =item Bad name after %s
430 (F) You started to name a symbol by using a package prefix, and then
431 didn't finish the symbol. In particular, you can't interpolate outside
440 $sym = "mypack::$var";
442 =item Bad plugin affecting keyword '%s'
444 (F) An extension using the keyword plugin mechanism violated the
447 =item Bad realloc() ignored
449 (S malloc) An internal routine called realloc() on something that
450 had never been malloc()ed in the first place. Mandatory, but can
451 be disabled by setting the environment variable C<PERL_BADFREE> to 1.
453 =item Bad symbol for array
455 (P) An internal request asked to add an array entry to something that
456 wasn't a symbol table entry.
458 =item Bad symbol for dirhandle
460 (P) An internal request asked to add a dirhandle entry to something
461 that wasn't a symbol table entry.
463 =item Bad symbol for filehandle
465 (P) An internal request asked to add a filehandle entry to something
466 that wasn't a symbol table entry.
468 =item Bad symbol for hash
470 (P) An internal request asked to add a hash entry to something that
471 wasn't a symbol table entry.
473 =item Bareword found in conditional
475 (W bareword) The compiler found a bareword where it expected a
476 conditional, which often indicates that an || or && was parsed as part
477 of the last argument of the previous construct, for example:
481 It may also indicate a misspelled constant that has been interpreted as
484 use constant TYPO => 1;
485 if (TYOP) { print "foo" }
487 The C<strict> pragma is useful in avoiding such errors.
489 =item Bareword "%s" not allowed while "strict subs" in use
491 (F) With "strict subs" in use, a bareword is only allowed as a
492 subroutine identifier, in curly brackets or to the left of the "=>"
493 symbol. Perhaps you need to predeclare a subroutine?
495 =item Bareword "%s" refers to nonexistent package
497 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
498 compiler saw no other uses of that namespace before that point. Perhaps
499 you need to predeclare a package?
501 =item BEGIN failed--compilation aborted
503 (F) An untrapped exception was raised while executing a BEGIN
504 subroutine. Compilation stops immediately and the interpreter is
507 =item BEGIN not safe after errors--compilation aborted
509 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
510 implies a C<BEGIN {}>) after one or more compilation errors had already
511 occurred. Since the intended environment for the C<BEGIN {}> could not
512 be guaranteed (due to the errors), and since subsequent code likely
513 depends on its correct operation, Perl just gave up.
515 =item \1 better written as $1
517 (W syntax) Outside of patterns, backreferences live on as variables.
518 The use of backslashes is grandfathered on the right-hand side of a
519 substitution, but stylistically it's better to use the variable form
520 because other Perl programmers will expect it, and it works better if
521 there are more than 9 backreferences.
523 =item Binary number > 0b11111111111111111111111111111111 non-portable
525 (W portable) The binary number you specified is larger than 2**32-1
526 (4294967295) and therefore non-portable between systems. See
527 L<perlport> for more on portability concerns.
529 =item bind() on closed socket %s
531 (W closed) You tried to do a bind on a closed socket. Did you forget to
532 check the return value of your socket() call? See L<perlfunc/bind>.
534 =item binmode() on closed filehandle %s
536 (W unopened) You tried binmode() on a filehandle that was never opened.
537 Check your control flow and number of arguments.
539 =item "\b{" is deprecated; use "\b\{" or "\b[{]" instead in regex; marked by <-- HERE in m/%s/
541 =item "\B{" is deprecated; use "\B\{" or "\B[{]" instead in regex; marked by <-- HERE in m/%s/
543 (W deprecated) Use of an unescaped "{" immediately following a
544 C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
545 itself in a future release. You can either precede the brace with a
546 backslash, or enclose it in square brackets; the latter is the way to go
547 if the pattern delimiters are C<{}>.
549 =item Bit vector size > 32 non-portable
551 (W portable) Using bit vector sizes larger than 32 is non-portable.
553 =item Bizarre copy of %s
555 (P) Perl detected an attempt to copy an internal value that is not
558 =item Buffer overflow in prime_env_iter: %s
560 (W internal) A warning peculiar to VMS. While Perl was preparing to
561 iterate over %ENV, it encountered a logical name or symbol definition
562 which was too long, so it was truncated to the string shown.
564 =item Bizarre SvTYPE [%d]
566 (P) When starting a new thread or return values from a thread, Perl
567 encountered an invalid data type.
569 =item Callback called exit
571 (F) A subroutine invoked from an external package via call_sv()
572 exited by calling exit.
574 =item %s() called too early to check prototype
576 (W prototype) You've called a function that has a prototype before the
577 parser saw a definition or declaration for it, and Perl could not check
578 that the call conforms to the prototype. You need to either add an
579 early prototype declaration for the subroutine in question, or move the
580 subroutine definition ahead of the call to get proper prototype
581 checking. Alternatively, if you are certain that you're calling the
582 function correctly, you may put an ampersand before the name to avoid
583 the warning. See L<perlsub>.
585 =item Cannot compress integer in pack
587 (F) An argument to pack("w",...) was too large to compress. The BER
588 compressed integer format can only be used with positive integers, and you
589 attempted to compress Infinity or a very large number (> 1e308).
590 See L<perlfunc/pack>.
592 =item Cannot compress negative numbers in pack
594 (F) An argument to pack("w",...) was negative. The BER compressed integer
595 format can only be used with positive integers. See L<perlfunc/pack>.
597 =item Cannot convert a reference to %s to typeglob
599 (F) You manipulated Perl's symbol table directly, stored a reference
600 in it, then tried to access that symbol via conventional Perl syntax.
601 The access triggers Perl to autovivify that typeglob, but it there is
602 no legal conversion from that type of reference to a typeglob.
604 =item Cannot copy to %s
606 (P) Perl detected an attempt to copy a value to an internal type that cannot
607 be directly assigned to.
609 =item Cannot find encoding "%s"
611 (S io) You tried to apply an encoding that did not exist to a filehandle,
612 either with open() or binmode().
614 =item Cannot set tied @DB::args
616 (F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
617 is not supported. (Before this error was added, it used to crash.)
619 =item Cannot tie unreifiable array
621 (P) You somehow managed to call C<tie> on an array that does not
622 keep a reference count on its arguments and cannot be made to
623 do so. Such arrays are not even supposed to be accessible to
624 Perl code, but are only used internally.
626 =item Can only compress unsigned integers in pack
628 (F) An argument to pack("w",...) was not an integer. The BER compressed
629 integer format can only be used with positive integers, and you attempted
630 to compress something else. See L<perlfunc/pack>.
632 =item Can't bless non-reference value
634 (F) Only hard references may be blessed. This is how Perl "enforces"
635 encapsulation of objects. See L<perlobj>.
637 =item Can't "break" in a loop topicalizer
639 (F) You called C<break>, but you're in a C<foreach> block rather than
640 a C<given> block. You probably meant to use C<next> or C<last>.
642 =item Can't "break" outside a given block
644 (F) You called C<break>, but you're not inside a C<given> block.
646 =item Can't call method "%s" on an undefined value
648 (F) You used the syntax of a method call, but the slot filled by the
649 object reference or package name contains an undefined value. Something
650 like this will reproduce the error:
653 process $BADREF 1,2,3;
654 $BADREF->process(1,2,3);
656 =item Can't call method "%s" on unblessed reference
658 (F) A method call must know in what package it's supposed to run. It
659 ordinarily finds this out from the object reference you supply, but you
660 didn't supply an object reference in this case. A reference isn't an
661 object reference until it has been blessed. See L<perlobj>.
663 =item Can't call method "%s" without a package or object reference
665 (F) You used the syntax of a method call, but the slot filled by the
666 object reference or package name contains an expression that returns a
667 defined value which is neither an object reference nor a package name.
668 Something like this will reproduce the error:
671 process $BADREF 1,2,3;
672 $BADREF->process(1,2,3);
674 =item Can't chdir to %s
676 (F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
677 that you can chdir to, possibly because it doesn't exist.
679 =item Can't check filesystem of script "%s" for nosuid
681 (P) For some reason you can't check the filesystem of the script for
684 =item Can't coerce %s to %s in %s
686 (F) Certain types of SVs, in particular real symbol table entries
687 (typeglobs), can't be forced to stop being what they are. So you can't
697 but then $foo no longer contains a glob.
699 =item Can't "continue" outside a when block
701 (F) You called C<continue>, but you're not inside a C<when>
704 =item Can't create pipe mailbox
706 (P) An error peculiar to VMS. The process is suffering from exhausted
707 quotas or other plumbing problems.
709 =item Can't declare %s in "%s"
711 (F) Only scalar, array, and hash variables may be declared as "my", "our" or
712 "state" variables. They must have ordinary identifiers as names.
714 =item Can't "default" outside a topicalizer
716 (F) You have used a C<default> block that is neither inside a
717 C<foreach> loop nor a C<given> block. (Note that this error is
718 issued on exit from the C<default> block, so you won't get the
719 error if you use an explicit C<continue>.)
721 =item Can't do inplace edit: %s is not a regular file
723 (S inplace) You tried to use the B<-i> switch on a special file, such as
724 a file in /dev, a FIFO or an uneditable directory. The file was ignored.
726 =item Can't do inplace edit on %s: %s
728 (S inplace) The creation of the new file failed for the indicated
731 =item Can't do inplace edit without backup
733 (F) You're on a system such as MS-DOS that gets confused if you try
734 reading from a deleted (but still opened) file. You have to say
735 C<-i.bak>, or some such.
737 =item Can't do inplace edit: %s would not be unique
739 (S inplace) Your filesystem does not support filenames longer than 14
740 characters and Perl was unable to create a unique filename during
741 inplace editing with the B<-i> switch. The file was ignored.
743 =item Can't do waitpid with flags
745 (F) This machine doesn't have either waitpid() or wait4(), so only
746 waitpid() without flags is emulated.
748 =item Can't emulate -%s on #! line
750 (F) The #! line specifies a switch that doesn't make sense at this
751 point. For example, it'd be kind of silly to put a B<-x> on the #!
754 =item Can't %s %s-endian %ss on this platform
756 (F) Your platform's byte-order is neither big-endian nor little-endian,
757 or it has a very strange pointer size. Packing and unpacking big- or
758 little-endian floating point values and pointers may not be possible.
759 See L<perlfunc/pack>.
761 =item Can't exec "%s": %s
763 (W exec) A system(), exec(), or piped open call could not execute the
764 named program for the indicated reason. Typical reasons include: the
765 permissions were wrong on the file, the file wasn't found in
766 C<$ENV{PATH}>, the executable in question was compiled for another
767 architecture, or the #! line in a script points to an interpreter that
768 can't be run for similar reasons. (Or maybe your system doesn't support
773 (F) Perl was trying to execute the indicated program for you because
774 that's what the #! line said. If that's not what you wanted, you may
775 need to mention "perl" on the #! line somewhere.
777 =item Can't execute %s
779 (F) You used the B<-S> switch, but the copies of the script to execute
780 found in the PATH did not have correct permissions.
782 =item Can't find an opnumber for "%s"
784 (F) A string of a form C<CORE::word> was given to prototype(), but there
785 is no builtin with the name C<word>.
787 =item Can't find %s character property "%s"
789 (F) You used C<\p{}> or C<\P{}> but the character property by that name
790 could not be found. Maybe you misspelled the name of the property?
791 See L<perluniprops/Properties accessible through \p{} and \P{}>
792 for a complete list of available properties.
794 =item Can't find label %s
796 (F) You said to goto a label that isn't mentioned anywhere that it's
797 possible for us to go to. See L<perlfunc/goto>.
799 =item Can't find %s on PATH
801 (F) You used the B<-S> switch, but the script to execute could not be
804 =item Can't find %s on PATH, '.' not in PATH
806 (F) You used the B<-S> switch, but the script to execute could not be
807 found in the PATH, or at least not with the correct permissions. The
808 script exists in the current directory, but PATH prohibits running it.
810 =item Can't find string terminator %s anywhere before EOF
812 (F) Perl strings can stretch over multiple lines. This message means
813 that the closing delimiter was omitted. Because bracketed quotes count
814 nesting levels, the following is missing its final parenthesis:
816 print q(The character '(' starts a side comment.);
818 If you're getting this error from a here-document, you may have
819 included unseen whitespace before or after your closing tag or there
820 may not be a linebreak after it. A good programmer's editor will have
821 a way to help you find these characters (or lack of characters). See
822 L<perlop> for the full details on here-documents.
824 =item Can't find Unicode property definition "%s"
826 (F) You may have tried to use C<\p> which means a Unicode
827 property (for example C<\p{Lu}> matches all uppercase
828 letters). If you did mean to use a Unicode property, see
829 L<perluniprops/Properties accessible through \p{} and \P{}>
830 for a complete list of available properties. If you didn't
831 mean to use a Unicode property, escape the C<\p>, either by
832 C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
837 (F) A fatal error occurred while trying to fork while opening a
840 =item Can't fork, trying again in 5 seconds
842 (W pipe) A fork in a piped open failed with EAGAIN and will be retried
845 =item Can't get filespec - stale stat buffer?
847 (S) A warning peculiar to VMS. This arises because of the difference
848 between access checks under VMS and under the Unix model Perl assumes.
849 Under VMS, access checks are done by filename, rather than by bits in
850 the stat buffer, so that ACLs and other protections can be taken into
851 account. Unfortunately, Perl assumes that the stat buffer contains all
852 the necessary information, and passes it, instead of the filespec, to
853 the access-checking routine. It will try to retrieve the filespec using
854 the device name and FID present in the stat buffer, but this works only
855 if you haven't made a subsequent call to the CRTL stat() routine,
856 because the device name is overwritten with each call. If this warning
857 appears, the name lookup failed, and the access-checking routine gave up
858 and returned FALSE, just to be conservative. (Note: The access-checking
859 routine knows about the Perl C<stat> operator and file tests, so you
860 shouldn't ever see this warning in response to a Perl command; it arises
861 only if some internal code takes stat buffers lightly.)
863 =item Can't get pipe mailbox device name
865 (P) An error peculiar to VMS. After creating a mailbox to act as a
866 pipe, Perl can't retrieve its name for later use.
868 =item Can't get SYSGEN parameter value for MAXBUF
870 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
871 mailbox buffers to be, and didn't get an answer.
873 =item Can't "goto" into the middle of a foreach loop
875 (F) A "goto" statement was executed to jump into the middle of a foreach
876 loop. You can't get there from here. See L<perlfunc/goto>.
878 =item Can't "goto" out of a pseudo block
880 (F) A "goto" statement was executed to jump out of what might look like
881 a block, except that it isn't a proper block. This usually occurs if
882 you tried to jump out of a sort() block or subroutine, which is a no-no.
883 See L<perlfunc/goto>.
885 =item Can't goto subroutine from a sort sub (or similar callback)
887 (F) The "goto subroutine" call can't be used to jump out of the
888 comparison sub for a sort(), or from a similar callback (such
889 as the reduce() function in List::Util).
891 =item Can't goto subroutine from an eval-%s
893 (F) The "goto subroutine" call can't be used to jump out of an eval
896 =item Can't goto subroutine outside a subroutine
898 (F) The deeply magical "goto subroutine" call can only replace one
899 subroutine call for another. It can't manufacture one out of whole
900 cloth. In general you should be calling it out of only an AUTOLOAD
901 routine anyway. See L<perlfunc/goto>.
903 =item Can't ignore signal CHLD, forcing to default
905 (W signal) Perl has detected that it is being run with the SIGCHLD
906 signal (sometimes known as SIGCLD) disabled. Since disabling this
907 signal will interfere with proper determination of exit status of child
908 processes, Perl has reset the signal to its default value. This
909 situation typically indicates that the parent program under which Perl
910 may be running (e.g. cron) is being very careless.
912 =item Can't kill a non-numeric process ID
914 (F) Process identifiers must be (signed) integers. It is a fatal error to
915 attempt to kill() an undefined, empty-string or otherwise non-numeric
918 =item Can't "last" outside a loop block
920 (F) A "last" statement was executed to break out of the current block,
921 except that there's this itty bitty problem called there isn't a current
922 block. Note that an "if" or "else" block doesn't count as a "loopish"
923 block, as doesn't a block given to sort(), map() or grep(). You can
924 usually double the curlies to get the same effect though, because the
925 inner curlies will be considered a block that loops once. See
928 =item Can't linearize anonymous symbol table
930 (F) Perl tried to calculate the method resolution order (MRO) of a
931 package, but failed because the package stash has no name.
933 =item Can't load '%s' for module %s
935 (F) The module you tried to load failed to load a dynamic extension.
936 This may either mean that you upgraded your version of perl to one
937 that is incompatible with your old dynamic extensions (which is known
938 to happen between major versions of perl), or (more likely) that your
939 dynamic extension was built against an older version of the library
940 that is installed on your system. You may need to rebuild your old
943 =item Can't localize lexical variable %s
945 (F) You used local on a variable name that was previously declared as a
946 lexical variable using "my" or "state". This is not allowed. If you
947 want to localize a package variable of the same name, qualify it with
950 =item Can't localize through a reference
952 (F) You said something like C<local $$ref>, which Perl can't currently
953 handle, because when it goes to restore the old value of whatever $ref
954 pointed to after the scope of the local() is finished, it can't be sure
955 that $ref will still be a reference.
957 =item Can't locate %s
959 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
960 Perl looks for the file in all the locations mentioned in @INC, unless
961 the file name included the full path to the file. Perhaps you need
962 to set the PERL5LIB or PERL5OPT environment variable to say where the
963 extra library is, or maybe the script needs to add the library name
964 to @INC. Or maybe you just misspelled the name of the file. See
965 L<perlfunc/require> and L<lib>.
967 =item Can't locate auto/%s.al in @INC
969 (F) A function (or method) was called in a package which allows
970 autoload, but there is no function to autoload. Most probable causes
971 are a misprint in a function/method name or a failure to C<AutoSplit>
972 the file, say, by doing C<make install>.
974 =item Can't locate loadable object for module %s in @INC
976 (F) The module you loaded is trying to load an external library, like
977 for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
978 unable to locate this library. See L<DynaLoader>.
980 =item Can't locate object method "%s" via package "%s"
982 (F) You called a method correctly, and it correctly indicated a package
983 functioning as a class, but that package doesn't define that particular
984 method, nor does any of its base classes. See L<perlobj>.
986 =item Can't locate package %s for @%s::ISA
988 (W syntax) The @ISA array contained the name of another package that
989 doesn't seem to exist.
991 =item Can't locate PerlIO%s
993 (F) You tried to use in open() a PerlIO layer that does not exist,
994 e.g. open(FH, ">:nosuchlayer", "somefile").
996 =item Can't make list assignment to %ENV on this system
998 (F) List assignment to %ENV is not supported on some systems, notably
1001 =item Can't make loaded symbols global on this platform while loading %s
1003 (W) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
1004 that symbols from the stated file are made available globally within the
1005 process, but that functionality is not available on this platform. Whilst
1006 the module likely will still work, this may prevent the perl interpreter
1007 from loading other XS-based extensions which need to link directly to
1008 functions defined in the C or XS code in the stated file.
1010 =item Can't modify %s in %s
1012 (F) You aren't allowed to assign to the item indicated, or otherwise try
1013 to change it, such as with an auto-increment.
1015 =item Can't modify nonexistent substring
1017 (P) The internal routine that does assignment to a substr() was handed
1020 =item Can't modify non-lvalue subroutine call
1022 (F) Subroutines meant to be used in lvalue context should be declared as
1023 such. See L<perlsub/"Lvalue subroutines">.
1025 =item Can't msgrcv to read-only var
1027 (F) The target of a msgrcv must be modifiable to be used as a receive
1030 =item Can't "next" outside a loop block
1032 (F) A "next" statement was executed to reiterate the current block, but
1033 there isn't a current block. Note that an "if" or "else" block doesn't
1034 count as a "loopish" block, as doesn't a block given to sort(), map() or
1035 grep(). You can usually double the curlies to get the same effect
1036 though, because the inner curlies will be considered a block that loops
1037 once. See L<perlfunc/next>.
1041 (F) You tried to run a perl built with MAD support with
1042 the PERL_XMLDUMP environment variable set, but the file
1043 named by that variable could not be opened.
1045 =item Can't open %s: %s
1047 (S inplace) The implicit opening of a file through use of the C<< <> >>
1048 filehandle, either implicitly under the C<-n> or C<-p> command-line
1049 switches, or explicitly, failed for the indicated reason. Usually
1050 this is because you don't have read permission for a file which
1051 you named on the command line.
1053 (F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1054 your operating system's equivalent) could not be opened.
1056 =item Can't open a reference
1058 (W io) You tried to open a scalar reference for reading or writing,
1059 using the 3-arg open() syntax:
1063 but your version of perl is compiled without perlio, and this form of
1064 open is not supported.
1066 =item Can't open bidirectional pipe
1068 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1069 You can try any of several modules in the Perl library to do this, such
1070 as IPC::Open2. Alternately, direct the pipe's output to a file using
1071 ">", and then read it in under a different file handle.
1073 =item Can't open error file %s as stderr
1075 (F) An error peculiar to VMS. Perl does its own command line
1076 redirection, and couldn't open the file specified after '2>' or '2>>' on
1077 the command line for writing.
1079 =item Can't open input file %s as stdin
1081 (F) An error peculiar to VMS. Perl does its own command line
1082 redirection, and couldn't open the file specified after '<' on the
1083 command line for reading.
1085 =item Can't open output file %s as stdout
1087 (F) An error peculiar to VMS. Perl does its own command line
1088 redirection, and couldn't open the file specified after '>' or '>>' on
1089 the command line for writing.
1091 =item Can't open output pipe (name: %s)
1093 (P) An error peculiar to VMS. Perl does its own command line
1094 redirection, and couldn't open the pipe into which to send data destined
1097 =item Can't open perl script "%s": %s
1099 (F) The script you specified can't be opened for the indicated reason.
1101 If you're debugging a script that uses #!, and normally relies on the
1102 shell's $PATH search, the -S option causes perl to do that search, so
1103 you don't have to type the path or C<`which $scriptname`>.
1105 =item Can't read CRTL environ
1107 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1108 from the CRTL's internal environment array and discovered the array was
1109 missing. You need to figure out where your CRTL misplaced its environ
1110 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1113 =item Can't "redo" outside a loop block
1115 (F) A "redo" statement was executed to restart the current block, but
1116 there isn't a current block. Note that an "if" or "else" block doesn't
1117 count as a "loopish" block, as doesn't a block given to sort(), map()
1118 or grep(). You can usually double the curlies to get the same effect
1119 though, because the inner curlies will be considered a block that
1120 loops once. See L<perlfunc/redo>.
1122 =item Can't remove %s: %s, skipping file
1124 (S inplace) You requested an inplace edit without creating a backup
1125 file. Perl was unable to remove the original file to replace it with
1126 the modified file. The file was left unmodified.
1128 =item Can't rename %s to %s: %s, skipping file
1130 (S inplace) The rename done by the B<-i> switch failed for some reason,
1131 probably because you don't have write permission to the directory.
1133 =item Can't reopen input pipe (name: %s) in binary mode
1135 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1136 to reopen it to accept binary data. Alas, it failed.
1138 =item Can't reset %ENV on this system
1140 (F) You called C<reset('E')> or similar, which tried to reset
1141 all variables in the current package beginning with "E". In
1142 the main package, that includes %ENV. Resetting %ENV is not
1143 supported on some systems, notably VMS.
1145 =item Can't resolve method "%s" overloading "%s" in package "%s"
1147 (F)(P) Error resolving overloading specified by a method name (as
1148 opposed to a subroutine reference): no such method callable via the
1149 package. If the method name is C<???>, this is an internal error.
1151 =item Can't return %s from lvalue subroutine
1153 (F) Perl detected an attempt to return illegal lvalues (such as
1154 temporary or readonly values) from a subroutine used as an lvalue. This
1157 =item Can't return outside a subroutine
1159 (F) The return statement was executed in mainline code, that is, where
1160 there was no subroutine call to return out of. See L<perlsub>.
1162 =item Can't return %s to lvalue scalar context
1164 (F) You tried to return a complete array or hash from an lvalue
1165 subroutine, but you called the subroutine in a way that made Perl
1166 think you meant to return only one value. You probably meant to
1167 write parentheses around the call to the subroutine, which tell
1168 Perl that the call should be in list context.
1170 =item Can't stat script "%s"
1172 (P) For some reason you can't fstat() the script even though you have it
1173 open already. Bizarre.
1175 =item Can't take log of %g
1177 (F) For ordinary real numbers, you can't take the logarithm of a
1178 negative number or zero. There's a Math::Complex package that comes
1179 standard with Perl, though, if you really want to do that for the
1182 =item Can't take sqrt of %g
1184 (F) For ordinary real numbers, you can't take the square root of a
1185 negative number. There's a Math::Complex package that comes standard
1186 with Perl, though, if you really want to do that.
1188 =item Can't undef active subroutine
1190 (F) You can't undefine a routine that's currently running. You can,
1191 however, redefine it while it's running, and you can even undef the
1192 redefined subroutine while the old routine is running. Go figure.
1194 =item Can't upgrade %s (%d) to %d
1196 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1197 into a more specialized kind of SV. The top several SV types are so
1198 specialized, however, that they cannot be interconverted. This message
1199 indicates that such a conversion was attempted.
1201 =item Can't use '%c' after -mname
1203 (F) You tried to call perl with the B<-m> switch, but you put something
1204 other than "=" after the module name.
1206 =item Can't use anonymous symbol table for method lookup
1208 (F) The internal routine that does method lookup was handed a symbol
1209 table that doesn't have a name. Symbol tables can become anonymous
1210 for example by undefining stashes: C<undef %Some::Package::>.
1212 =item Can't use an undefined value as %s reference
1214 (F) A value used as either a hard reference or a symbolic reference must
1215 be a defined value. This helps to delurk some insidious errors.
1217 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1219 (F) Only hard references are allowed by "strict refs". Symbolic
1220 references are disallowed. See L<perlref>.
1222 =item Can't use %! because Errno.pm is not available
1224 (F) The first time the C<%!> hash is used, perl automatically loads the
1225 Errno.pm module. The Errno module is expected to tie the %! hash to
1226 provide symbolic names for C<$!> errno values.
1228 =item Can't use both '<' and '>' after type '%c' in %s
1230 (F) A type cannot be forced to have both big-endian and little-endian
1231 byte-order at the same time, so this combination of modifiers is not
1232 allowed. See L<perlfunc/pack>.
1234 =item Can't use %s for loop variable
1236 (F) Only a simple scalar variable may be used as a loop variable on a
1239 =item Can't use global %s in "%s"
1241 (F) You tried to declare a magical variable as a lexical variable. This
1242 is not allowed, because the magic can be tied to only one location
1243 (namely the global variable) and it would be incredibly confusing to
1244 have variables in your program that looked like magical variables but
1247 =item Can't use '%c' in a group with different byte-order in %s
1249 (F) You attempted to force a different byte-order on a type
1250 that is already inside a group with a byte-order modifier.
1251 For example you cannot force little-endianness on a type that
1252 is inside a big-endian group.
1254 =item Can't use "my %s" in sort comparison
1256 (F) The global variables $a and $b are reserved for sort comparisons.
1257 You mentioned $a or $b in the same line as the <=> or cmp operator,
1258 and the variable had earlier been declared as a lexical variable.
1259 Either qualify the sort variable with the package name, or rename the
1262 =item Can't use %s ref as %s ref
1264 (F) You've mixed up your reference types. You have to dereference a
1265 reference of the type needed. You can use the ref() function to
1266 test the type of the reference, if need be.
1268 =item Can't use string ("%s") as %s ref while "strict refs" in use
1270 (F) You've told Perl to dereference a string, something which
1271 C<use strict> blocks to prevent it happening accidentally. See
1272 L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1273 in a double-quoted string immediately before interpolating a variable,
1274 for example in C<"user @$twitter_id">, which says to treat the contents
1275 of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1276 symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
1278 =item Can't use subscript on %s
1280 (F) The compiler tried to interpret a bracketed expression as a
1281 subscript. But to the left of the brackets was an expression that
1282 didn't look like a hash or array reference, or anything else subscriptable.
1284 =item Can't use \%c to mean $%c in expression
1286 (W syntax) In an ordinary expression, backslash is a unary operator that
1287 creates a reference to its argument. The use of backslash to indicate a
1288 backreference to a matched substring is valid only as part of a regular
1289 expression pattern. Trying to do this in ordinary Perl code produces a
1290 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1293 =item Can't weaken a nonreference
1295 (F) You attempted to weaken something that was not a reference. Only
1296 references can be weakened.
1298 =item Can't "when" outside a topicalizer
1300 (F) You have used a when() block that is neither inside a C<foreach>
1301 loop nor a C<given> block. (Note that this error is issued on exit
1302 from the C<when> block, so you won't get the error if the match fails,
1303 or if you use an explicit C<continue>.)
1305 =item Can't x= to read-only value
1307 (F) You tried to repeat a constant value (often the undefined value)
1308 with an assignment operator, which implies modifying the value itself.
1309 Perhaps you need to copy the value to a temporary, and repeat that.
1311 =item Character following "\c" must be ASCII
1313 (F)(W deprecated, syntax) In C<\cI<X>>, I<X> must be an ASCII character.
1314 It is planned to make this fatal in all instances in Perl 5.18. In the
1315 cases where it isn't fatal, the character this evaluates to is
1316 derived by exclusive or'ing the code point of this character with 0x40.
1318 Note that non-alphabetic ASCII characters are discouraged here as well.
1320 =item Character in 'C' format wrapped in pack
1326 where $x is either less than 0 or more than 255; the C<"C"> format is
1327 only for encoding native operating system characters (ASCII, EBCDIC,
1328 and so on) and not for Unicode characters, so Perl behaved as if you meant
1332 If you actually want to pack Unicode codepoints, use the C<"U"> format
1335 =item Character in 'W' format wrapped in pack
1341 where $x is either less than 0 or more than 255. However, C<U0>-mode
1342 expects all values to fall in the interval [0, 255], so Perl behaved
1345 pack("U0W", $x & 255)
1347 =item Character in 'c' format wrapped in pack
1353 where $x is either less than -128 or more than 127; the C<"c"> format
1354 is only for encoding native operating system characters (ASCII, EBCDIC,
1355 and so on) and not for Unicode characters, so Perl behaved as if you meant
1357 pack("c", $x & 255);
1359 If you actually want to pack Unicode codepoints, use the C<"U"> format
1362 =item Character in '%c' format wrapped in unpack
1364 (W unpack) You tried something like
1366 unpack("H", "\x{2a1}")
1368 where the format expects to process a byte (a character with a value
1369 below 256), but a higher value was provided instead. Perl uses the
1370 value modulus 256 instead, as if you had provided:
1372 unpack("H", "\x{a1}")
1374 =item Character(s) in '%c' format wrapped in pack
1376 (W pack) You tried something like
1378 pack("u", "\x{1f3}b")
1380 where the format expects to process a sequence of bytes (character with a
1381 value below 256), but some of the characters had a higher value. Perl
1382 uses the character values modulus 256 instead, as if you had provided:
1384 pack("u", "\x{f3}b")
1386 =item Character(s) in '%c' format wrapped in unpack
1388 (W unpack) You tried something like
1390 unpack("s", "\x{1f3}b")
1392 where the format expects to process a sequence of bytes (character with a
1393 value below 256), but some of the characters had a higher value. Perl
1394 uses the character values modulus 256 instead, as if you had provided:
1396 unpack("s", "\x{f3}b")
1398 =item "\c{" is deprecated and is more clearly written as ";"
1400 (D deprecated, syntax) The C<\cI<X>> construct is intended to be a way
1401 to specify non-printable characters. You used it with a "{" which
1402 evaluates to ";", which is printable. It is planned to remove the
1403 ability to specify a semi-colon this way in Perl 5.18. Just use a
1404 semi-colon or a backslash-semi-colon without the "\c".
1406 =item "\c%c" is more clearly written simply as "%s"
1408 (W syntax) The C<\cI<X>> construct is intended to be a way to specify
1409 non-printable characters. You used it for a printable one, which is better
1410 written as simply itself, perhaps preceded by a backslash for non-word
1413 =item Cloning substitution context is unimplemented
1415 (F) Creating a new thread inside the C<s///> operator is not supported.
1417 =item close() on unopened filehandle %s
1419 (W unopened) You tried to close a filehandle that was never opened.
1421 =item closedir() attempted on invalid dirhandle %s
1423 (W io) The dirhandle you tried to close is either closed or not really
1424 a dirhandle. Check your control flow.
1426 =item Closure prototype called
1428 (F) If a closure has attributes, the subroutine passed to an attribute
1429 handler is the prototype that is cloned when a new closure is created.
1430 This subroutine cannot be called.
1432 =item Code missing after '/'
1434 (F) You had a (sub-)template that ends with a '/'. There must be
1435 another template code following the slash. See L<perlfunc/pack>.
1437 =item Code point 0x%X is not Unicode, may not be portable
1439 =item Code point 0x%X is not Unicode, all \p{} matches fail; all \P{} matches
1442 (S utf8, non_unicode) You had a code point above the Unicode maximum
1445 Perl allows strings to contain a superset of Unicode code points, up
1446 to the limit of what is storable in an unsigned integer on your system,
1447 but these may not be accepted by other languages/systems. At one time,
1448 it was legal in some standards to have code points up to 0x7FFF_FFFF,
1449 but not higher. Code points above 0xFFFF_FFFF require larger than a
1452 None of the Unicode or Perl-defined properties will match a non-Unicode
1453 code point. For example,
1455 chr(0x7FF_FFFF) =~ /\p{Any}/
1457 will not match, because the code point is not in Unicode. But
1459 chr(0x7FF_FFFF) =~ /\P{Any}/
1463 This may be counterintuitive at times, as both these fail:
1465 chr(0x110000) =~ /\p{ASCII_Hex_Digit=True}/ # Fails.
1466 chr(0x110000) =~ /\p{ASCII_Hex_Digit=False}/ # Also fails!
1468 and both these succeed:
1470 chr(0x110000) =~ /\P{ASCII_Hex_Digit=True}/ # Succeeds.
1471 chr(0x110000) =~ /\P{ASCII_Hex_Digit=False}/ # Also succeeds!
1473 =item %s: Command not found
1475 (A) You've accidentally run your script through B<csh> or another shell
1476 shell instead of Perl. Check the #! line, or manually feed your script
1477 into Perl yourself. The #! line at the top of your file could look like
1481 =item Compilation failed in require
1483 (F) Perl could not compile a file specified in a C<require> statement.
1484 Perl uses this generic message when none of the errors that it
1485 encountered were severe enough to halt compilation immediately.
1487 =item Complex regular subexpression recursion limit (%d) exceeded
1489 (W regexp) The regular expression engine uses recursion in complex
1490 situations where back-tracking is required. Recursion depth is limited
1491 to 32766, or perhaps less in architectures where the stack cannot grow
1492 arbitrarily. ("Simple" and "medium" situations are handled without
1493 recursion and are not subject to a limit.) Try shortening the string
1494 under examination; looping in Perl code (e.g. with C<while>) rather than
1495 in the regular expression engine; or rewriting the regular expression so
1496 that it is simpler or backtracks less. (See L<perlfaq2> for information
1497 on I<Mastering Regular Expressions>.)
1499 =item cond_broadcast() called on unlocked variable
1501 (W threads) Within a thread-enabled program, you tried to
1502 call cond_broadcast() on a variable which wasn't locked.
1503 The cond_broadcast() function is used to wake up another thread
1504 that is waiting in a cond_wait(). To ensure that the signal isn't
1505 sent before the other thread has a chance to enter the wait, it
1506 is usual for the signaling thread first to wait for a lock on
1507 variable. This lock attempt will only succeed after the other
1508 thread has entered cond_wait() and thus relinquished the lock.
1510 =item cond_signal() called on unlocked variable
1512 (W threads) Within a thread-enabled program, you tried to
1513 call cond_signal() on a variable which wasn't locked. The
1514 cond_signal() function is used to wake up another thread that
1515 is waiting in a cond_wait(). To ensure that the signal isn't
1516 sent before the other thread has a chance to enter the wait, it
1517 is usual for the signaling thread first to wait for a lock on
1518 variable. This lock attempt will only succeed after the other
1519 thread has entered cond_wait() and thus relinquished the lock.
1521 =item connect() on closed socket %s
1523 (W closed) You tried to do a connect on a closed socket. Did you forget
1524 to check the return value of your socket() call? See
1525 L<perlfunc/connect>.
1527 =item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1529 (F) The subroutine registered to handle constant overloading
1530 (see L<overload>) or a custom charnames handler (see
1531 L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1533 =item Constant(%s): $^H{%s} is not defined
1535 (F) The parser found inconsistencies while attempting to define an
1536 overloaded constant. Perhaps you forgot to load the corresponding
1537 L<overload> pragma?.
1539 =item Constant(%s) unknown
1541 (F) The parser found inconsistencies either while attempting to define
1542 an overloaded constant, or when trying to find the character name
1543 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1544 corresponding L<overload> pragma?.
1546 =item Constant is not %s reference
1548 (F) A constant value (perhaps declared using the C<use constant> pragma)
1549 is being dereferenced, but it amounts to the wrong type of reference.
1550 The message indicates the type of reference that was expected. This
1551 usually indicates a syntax error in dereferencing the constant value.
1552 See L<perlsub/"Constant Functions"> and L<constant>.
1554 =item Constant subroutine %s redefined
1556 (W redefine)(S) You redefined a subroutine which had previously
1557 been eligible for inlining. See L<perlsub/"Constant Functions">
1558 for commentary and workarounds.
1560 =item Constant subroutine %s undefined
1562 (W misc) You undefined a subroutine which had previously been eligible
1563 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1566 =item Copy method did not return a reference
1568 (F) The method which overloads "=" is buggy. See
1569 L<overload/Copy Constructor>.
1571 =item &CORE::%s cannot be called directly
1573 (F) You tried to call a subroutine in the C<CORE::> namespace
1574 with C<&foo> syntax or through a reference. Some subroutines
1575 in this package cannot yet be called that way, but must be
1576 called as barewords. Something like this will work:
1578 BEGIN { *shove = \&CORE::push; }
1579 shove @array, 1,2,3; # pushes on to @array
1581 =item CORE::%s is not a keyword
1583 (F) The CORE:: namespace is reserved for Perl keywords.
1585 =item corrupted regexp pointers
1587 (P) The regular expression engine got confused by what the regular
1588 expression compiler gave it.
1590 =item corrupted regexp program
1592 (P) The regular expression engine got passed a regexp program without a
1595 =item Corrupt malloc ptr 0x%x at 0x%x
1597 (P) The malloc package that comes with Perl had an internal failure.
1599 =item Count after length/code in unpack
1601 (F) You had an unpack template indicating a counted-length string, but
1602 you have also specified an explicit size for the string. See
1605 =item Deep recursion on anonymous subroutine
1607 =item Deep recursion on subroutine "%s"
1609 (W recursion) This subroutine has called itself (directly or indirectly)
1610 100 times more than it has returned. This probably indicates an
1611 infinite recursion, unless you're writing strange benchmark programs, in
1612 which case it indicates something else.
1614 This threshold can be changed from 100, by recompiling the F<perl> binary,
1615 setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1617 =item defined(@array) is deprecated
1619 (D deprecated) defined() is not usually useful on arrays because it
1620 checks for an undefined I<scalar> value. If you want to see if the
1621 array is empty, just use C<if (@array) { # not empty }> for example.
1623 =item defined(%hash) is deprecated
1625 (D deprecated) C<defined()> is not usually right on hashes and has been
1626 discouraged since 5.004.
1628 Although C<defined %hash> is false on a plain not-yet-used hash, it
1629 becomes true in several non-obvious circumstances, including iterators,
1630 weak references, stash names, even remaining true after C<undef %hash>.
1631 These things make C<defined %hash> fairly useless in practice.
1633 If a check for non-empty is what you wanted then just put it in boolean
1634 context (see L<perldata/Scalar values>):
1640 If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1641 variable exists then that's never really been reliable, and isn't
1642 a good way to enquire about the features of a package, or whether
1646 =item (?(DEFINE)....) does not allow branches in regex; marked by <-- HERE in
1649 (F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
1650 most likely cause of this error is that you left out a parenthesis inside
1651 of the C<....> part.
1653 The <-- HERE shows whereabouts in the regular expression the problem was
1656 =item %s defines neither package nor VERSION--version check failed
1658 (F) You said something like "use Module 42" but in the Module file
1659 there are neither package declarations nor a C<$VERSION>.
1661 =item Delimiter for here document is too long
1663 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1664 long for Perl to handle. You have to be seriously twisted to write code
1665 that triggers this error.
1667 =item Deprecated use of my() in false conditional
1669 (D deprecated) You used a declaration similar to C<my $x if 0>. There
1670 has been a long-standing bug in Perl that causes a lexical variable
1671 not to be cleared at scope exit when its declaration includes a false
1672 conditional. Some people have exploited this bug to achieve a kind of
1673 static variable. Since we intend to fix this bug, we don't want people
1674 relying on this behavior. You can achieve a similar static effect by
1675 declaring the variable in a separate block outside the function, eg
1677 sub f { my $x if 0; return $x++ }
1681 { my $x; sub f { return $x++ } }
1683 Beginning with perl 5.9.4, you can also use C<state> variables to have
1684 lexicals that are initialized only once (see L<feature>):
1686 sub f { state $x; return $x++ }
1688 =item DESTROY created new reference to dead object '%s'
1690 (F) A DESTROY() method created a new reference to the object which is
1691 just being DESTROYed. Perl is confused, and prefers to abort rather
1692 than to create a dangling reference.
1694 =item Did not produce a valid header
1698 =item %s did not return a true value
1700 (F) A required (or used) file must return a true value to indicate that
1701 it compiled correctly and ran its initialization code correctly. It's
1702 traditional to end such a file with a "1;", though any true value would
1703 do. See L<perlfunc/require>.
1705 =item (Did you mean &%s instead?)
1707 (W misc) You probably referred to an imported subroutine &FOO as $FOO or
1710 =item (Did you mean "local" instead of "our"?)
1712 (W misc) Remember that "our" does not localize the declared global
1713 variable. You have declared it again in the same lexical scope, which
1716 =item (Did you mean $ or @ instead of %?)
1718 (W) You probably said %hash{$key} when you meant $hash{$key} or
1719 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1724 (F) You passed die() an empty string (the equivalent of C<die "">) or
1725 you called it with no args and C<$@> was empty.
1727 =item Document contains no data
1731 =item %s does not define %s::VERSION--version check failed
1733 (F) You said something like "use Module 42" but the Module did not
1734 define a C<$VERSION.>
1736 =item '/' does not take a repeat count
1738 (F) You cannot put a repeat count of any kind right after the '/' code.
1739 See L<perlfunc/pack>.
1741 =item Don't know how to handle magic of type '%s'
1743 (P) The internal handling of magical variables has been cursed.
1745 =item do_study: out of memory
1747 (P) This should have been caught by safemalloc() instead.
1749 =item (Do you need to predeclare %s?)
1751 (S syntax) This is an educated guess made in conjunction with the message
1752 "%s found where operator expected". It often means a subroutine or module
1753 name is being referenced that hasn't been declared yet. This may be
1754 because of ordering problems in your file, or because of a missing
1755 "sub", "package", "require", or "use" statement. If you're referencing
1756 something that isn't defined yet, you don't actually have to define the
1757 subroutine or package before the current location. You can use an empty
1758 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1760 =item dump() better written as CORE::dump()
1762 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1763 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1765 =item dump is not supported
1767 (F) Your machine doesn't support dump/undump.
1769 =item Duplicate free() ignored
1771 (S malloc) An internal routine called free() on something that had
1774 =item Duplicate modifier '%c' after '%c' in %s
1776 (W unpack) You have applied the same modifier more than once after a
1777 type in a pack template. See L<perlfunc/pack>.
1779 =item elseif should be elsif
1781 (S syntax) There is no keyword "elseif" in Perl because Larry thinks
1782 it's ugly. Your code will be interpreted as an attempt to call a method
1783 named "elseif" for the class returned by the following block. This is
1784 unlikely to be what you want.
1788 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1789 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1790 a regular expression without specifying the property name.
1792 =item entering effective %s failed
1794 (F) While under the C<use filetest> pragma, switching the real and
1795 effective uids or gids failed.
1797 =item %ENV is aliased to %s
1799 (F) You're running under taint mode, and the C<%ENV> variable has been
1800 aliased to another hash, so it doesn't reflect anymore the state of the
1801 program's environment. This is potentially insecure.
1803 =item Error converting file specification %s
1805 (F) An error peculiar to VMS. Because Perl may have to deal with file
1806 specifications in either VMS or Unix syntax, it converts them to a
1807 single form when it must operate on them directly. Either you've passed
1808 an invalid file specification to Perl, or you've found a case the
1809 conversion routines don't handle. Drat.
1811 =item Escape literal pattern white space under /x
1813 (D deprecated) You compiled a regular expression pattern with C</x> to
1814 ignore white space, and you used, as a literal, one of the characters
1815 that Perl plans to eventually treat as white space. The character must
1816 be escaped somehow, or it will work differently on a future Perl that
1817 does treat it as white space. The easiest way is to insert a backslash
1818 immediately before it, or to enclose it with square brackets. This
1819 change is to bring Perl into conformance with Unicode recommendations.
1820 Here are the five characters that generate this warning:
1822 U+200E LEFT-TO-RIGHT MARK,
1823 U+200F RIGHT-TO-LEFT MARK,
1824 U+2028 LINE SEPARATOR,
1826 U+2029 PARAGRAPH SEPARATOR.
1828 =item Eval-group in insecure regular expression
1830 (F) Perl detected tainted data when trying to compile a regular
1831 expression that contains the C<(?{ ... })> zero-width assertion, which
1832 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1834 =item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
1836 (F) Perl tried to compile a regular expression containing the
1837 C<(?{ ... })> zero-width assertion at run time, as it would when the
1838 pattern contains interpolated values. Since that is a security risk,
1839 it is not allowed. If you insist, you may still do this by using the
1840 C<re 'eval'> pragma or by explicitly building the pattern from an
1841 interpolated string at run time and using that in an eval(). See
1842 L<perlre/(?{ code })>.
1844 =item Eval-group not allowed, use re 'eval' in regex m/%s/
1846 (F) A regular expression contained the C<(?{ ... })> zero-width
1847 assertion, but that construct is only allowed when the C<use re 'eval'>
1848 pragma is in effect. See L<perlre/(?{ code })>.
1850 =item EVAL without pos change exceeded limit in regex; marked by <-- HERE in
1853 (F) You used a pattern that nested too many EVAL calls without consuming
1854 any text. Restructure the pattern so that text is consumed.
1856 The <-- HERE shows whereabouts in the regular expression the problem was
1859 =item Excessively long <> operator
1861 (F) The contents of a <> operator may not exceed the maximum size of a
1862 Perl identifier. If you're just trying to glob a long list of
1863 filenames, try using the glob() operator, or put the filenames into a
1864 variable and glob that.
1866 =item exec? I'm not *that* kind of operating system
1868 (F) The C<exec> function is not implemented on some systems, e.g., Symbian
1869 OS. See L<perlport>.
1871 =item Execution of %s aborted due to compilation errors.
1873 (F) The final summary message when a Perl compilation fails.
1875 =item Exiting eval via %s
1877 (W exiting) You are exiting an eval by unconventional means, such as a
1878 goto, or a loop control statement.
1880 =item Exiting format via %s
1882 (W exiting) You are exiting a format by unconventional means, such as a
1883 goto, or a loop control statement.
1885 =item Exiting pseudo-block via %s
1887 (W exiting) You are exiting a rather special block construct (like a
1888 sort block or subroutine) by unconventional means, such as a goto, or a
1889 loop control statement. See L<perlfunc/sort>.
1891 =item Exiting subroutine via %s
1893 (W exiting) You are exiting a subroutine by unconventional means, such
1894 as a goto, or a loop control statement.
1896 =item Exiting substitution via %s
1898 (W exiting) You are exiting a substitution by unconventional means, such
1899 as a return, a goto, or a loop control statement.
1901 =item Experimental "%s" subs not enabled
1903 (F) To use lexical subs, you must first enable them:
1905 no warnings 'experimental::lexical_subs';
1906 use feature 'lexical_subs';
1909 =item Explicit blessing to '' (assuming package main)
1911 (W misc) You are blessing a reference to a zero length string. This has
1912 the effect of blessing the reference into the package main. This is
1913 usually not what you want. Consider providing a default target package,
1914 e.g. bless($ref, $p || 'MyPackage');
1916 =item %s: Expression syntax
1918 (A) You've accidentally run your script through B<csh> instead of Perl.
1919 Check the #! line, or manually feed your script into Perl yourself.
1921 =item %s failed--call queue aborted
1923 (F) An untrapped exception was raised while executing a UNITCHECK,
1924 CHECK, INIT, or END subroutine. Processing of the remainder of the
1925 queue of such routines has been prematurely ended.
1927 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1929 (W regexp) A character class range must start and end at a literal
1930 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1931 in your false range is interpreted as a literal "-". Consider quoting the
1932 "-", "\-". The <-- HERE shows whereabouts in the regular expression the
1933 problem was discovered. See L<perlre>.
1935 =item Fatal VMS error (status=%d) at %s, line %d
1937 (P) An error peculiar to VMS. Something untoward happened in a VMS
1938 system service or RTL routine; Perl's exit status should provide more
1939 details. The filename in "at %s" and the line number in "line %d" tell
1940 you which section of the Perl source code is distressed.
1942 =item fcntl is not implemented
1944 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1945 PDP-11 or something?
1947 =item FETCHSIZE returned a negative value
1949 (F) A tied array claimed to have a negative number of elements, which
1952 =item Field too wide in 'u' format in pack
1954 (W pack) Each line in an uuencoded string starts with a length indicator
1955 which can't encode values above 63. So there is no point in asking for
1956 a line length bigger than that. Perl will behave as if you specified
1957 C<u63> as the format.
1959 =item Filehandle %s opened only for input
1961 (W io) You tried to write on a read-only filehandle. If you intended
1962 it to be a read-write filehandle, you needed to open it with "+<" or
1963 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1964 write the file, use ">" or ">>". See L<perlfunc/open>.
1966 =item Filehandle %s opened only for output
1968 (W io) You tried to read from a filehandle opened only for writing, If
1969 you intended it to be a read/write filehandle, you needed to open it
1970 with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1971 read from the file, use "<". See L<perlfunc/open>. Another possibility
1972 is that you attempted to open filedescriptor 0 (also known as STDIN) for
1973 output (maybe you closed STDIN earlier?).
1975 =item Filehandle %s reopened as %s only for input
1977 (W io) You opened for reading a filehandle that got the same filehandle id
1978 as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
1981 =item Filehandle STDIN reopened as %s only for output
1983 (W io) You opened for writing a filehandle that got the same filehandle id
1984 as STDIN. This occurred because you closed STDIN previously.
1986 =item Final $ should be \$ or $name
1988 (F) You must now decide whether the final $ in a string was meant to be
1989 a literal dollar sign, or was meant to introduce a variable name that
1990 happens to be missing. So you have to put either the backslash or the
1993 =item flock() on closed filehandle %s
1995 (W closed) The filehandle you're attempting to flock() got itself closed
1996 some time before now. Check your control flow. flock() operates on
1997 filehandles. Are you attempting to call flock() on a dirhandle by the
2000 =item Format not terminated
2002 (F) A format must be terminated by a line with a solitary dot. Perl got
2003 to the end of your file without finding such a line.
2005 =item Format %s redefined
2007 (W redefine) You redefined a format. To suppress this warning, say
2010 no warnings 'redefine';
2011 eval "format NAME =...";
2014 =item Found = in conditional, should be ==
2024 (or something like that).
2026 =item %s found where operator expected
2028 (S syntax) The Perl lexer knows whether to expect a term or an operator.
2029 If it sees what it knows to be a term when it was expecting to see an
2030 operator, it gives you this warning. Usually it indicates that an
2031 operator or delimiter was omitted, such as a semicolon.
2033 =item gdbm store returned %d, errno %d, key "%s"
2035 (S) A warning from the GDBM_File extension that a store failed.
2037 =item gethostent not implemented
2039 (F) Your C library apparently doesn't implement gethostent(), probably
2040 because if it did, it'd feel morally obligated to return every hostname
2043 =item get%sname() on closed socket %s
2045 (W closed) You tried to get a socket or peer socket name on a closed
2046 socket. Did you forget to check the return value of your socket() call?
2048 =item getpwnam returned invalid UIC %#o for user "%s"
2050 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2051 C<getpwnam> operator returned an invalid UIC.
2053 =item getsockopt() on closed socket %s
2055 (W closed) You tried to get a socket option on a closed socket. Did you
2056 forget to check the return value of your socket() call? See
2057 L<perlfunc/getsockopt>.
2059 =item Global symbol "%s" requires explicit package name
2061 (F) You've said "use strict" or "use strict vars", which indicates
2062 that all variables must either be lexically scoped (using "my" or "state"),
2063 declared beforehand using "our", or explicitly qualified to say
2064 which package the global variable is in (using "::").
2066 =item glob failed (%s)
2068 (S glob) Something went wrong with the external program(s) used
2069 for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2070 pattern that caused the external program to fail and exit with a
2071 nonzero status. If the message indicates that the abnormal exit
2072 resulted in a coredump, this may also mean that your csh (C shell)
2073 is broken. If so, you should change all of the csh-related variables
2074 in config.sh: If you have tcsh, make the variables refer to it as
2075 if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2076 all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
2077 think csh is missing. In either case, after editing config.sh, run
2078 C<./Configure -S> and rebuild Perl.
2080 =item Glob not terminated
2082 (F) The lexer saw a left angle bracket in a place where it was expecting
2083 a term, so it's looking for the corresponding right angle bracket, and
2084 not finding it. Chances are you left some needed parentheses out
2085 earlier in the line, and you really meant a "less than".
2087 =item gmtime(%f) too large
2089 (W overflow) You called C<gmtime> with a number that was larger than
2090 it can reliably handle and C<gmtime> probably returned the wrong
2091 date. This warning is also triggered with NaN (the special
2092 not-a-number value).
2094 =item gmtime(%f) too small
2096 (W overflow) You called C<gmtime> with a number that was smaller than
2097 it can reliably handle and C<gmtime> probably returned the wrong date.
2099 =item Got an error from DosAllocMem
2101 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2102 version of Perl, and this should not happen anyway.
2104 =item goto must have label
2106 (F) Unlike with "next" or "last", you're not allowed to goto an
2107 unspecified destination. See L<perlfunc/goto>.
2109 =item Goto undefined subroutine%s
2111 (F) You tried to call a subroutine with C<goto &sub> syntax, but
2112 the indicated subroutine hasn't been defined, or if it was, it
2113 has since been undefined.
2115 =item ()-group starts with a count
2117 (F) A ()-group started with a count. A count is supposed to follow
2118 something: a template character or a ()-group. See L<perlfunc/pack>.
2120 =item Group name must start with a non-digit word character in regex; marked by
2123 (F) Group names must follow the rules for perl identifiers, meaning
2124 they must start with a non-digit word character. A common cause of
2125 this error is using (?&0) instead of (?0). See L<perlre>.
2127 =item %s had compilation errors.
2129 (F) The final summary message when a C<perl -c> fails.
2131 =item Had to create %s unexpectedly
2133 (S internal) A routine asked for a symbol from a symbol table that ought
2134 to have existed already, but for some reason it didn't, and had to be
2135 created on an emergency basis to prevent a core dump.
2137 =item Hash %%s missing the % in argument %d of %s()
2139 (D deprecated) Really old Perl let you omit the % on hash names in some
2140 spots. This is now heavily deprecated.
2142 =item %s has too many errors
2144 (F) The parser has given up trying to parse the program after 10 errors.
2145 Further error messages would likely be uninformative.
2147 =item Hexadecimal number > 0xffffffff non-portable
2149 (W portable) The hexadecimal number you specified is larger than 2**32-1
2150 (4294967295) and therefore non-portable between systems. See
2151 L<perlport> for more on portability concerns.
2153 =item -i used with no filenames on the command line, reading from STDIN
2155 (S inplace) The C<-i> option was passed on the command line, indicating
2156 that the script is intended to edit files inplace, but no files were
2157 given. This is usually a mistake, since editing STDIN inplace doesn't
2158 make sense, and can be confusing because it can make perl look like
2159 it is hanging when it is really just trying to read from STDIN. You
2160 should either pass a filename to edit, or remove C<-i> from the command
2161 line. See L<perlrun> for more details.
2163 =item Identifier too long
2165 (F) Perl limits identifiers (names for variables, functions, etc.) to
2166 about 250 characters for simple names, and somewhat more for compound
2167 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2168 of Perl are likely to eliminate these arbitrary limitations.
2170 =item Ignoring zero length \N{} in character class in regex; marked by <-- HERE in m/%s/
2172 (W regexp) Named Unicode character escapes C<(\N{...})> may return a zero-length
2173 sequence. When such an escape is used in a character class its
2174 behaviour is not well defined. Check that the correct escape has
2175 been used, and the correct charname handler is in scope.
2177 =item Illegal binary digit %s
2179 (F) You used a digit other than 0 or 1 in a binary number.
2181 =item Illegal binary digit %s ignored
2183 (W digit) You may have tried to use a digit other than 0 or 1 in a
2184 binary number. Interpretation of the binary number stopped before the
2187 =item Illegal character after '_' in prototype for %s : %s
2189 (W illegalproto) An illegal character was found in a prototype declaration.
2190 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2192 =item Illegal character \%o (carriage return)
2194 (F) Perl normally treats carriage returns in the program text as it
2195 would any other whitespace, which means you should never see this error
2196 when Perl was built using standard options. For some reason, your
2197 version of Perl appears to have been built without this support. Talk
2198 to your Perl administrator.
2200 =item Illegal character in prototype for %s : %s
2202 (W illegalproto) An illegal character was found in a prototype declaration.
2203 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2205 =item Illegal declaration of anonymous subroutine
2207 (F) When using the C<sub> keyword to construct an anonymous subroutine,
2208 you must always specify a block of code. See L<perlsub>.
2210 =item Illegal declaration of subroutine %s
2212 (F) A subroutine was not declared correctly. See L<perlsub>.
2214 =item Illegal division by zero
2216 (F) You tried to divide a number by 0. Either something was wrong in
2217 your logic, or you need to put a conditional in to guard against
2220 =item Illegal hexadecimal digit %s ignored
2222 (W digit) You may have tried to use a character other than 0 - 9 or
2223 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2224 number stopped before the illegal character.
2226 =item Illegal modulus zero
2228 (F) You tried to divide a number by 0 to get the remainder. Most
2229 numbers don't take to this kindly.
2231 =item Illegal number of bits in vec
2233 (F) The number of bits in vec() (the third argument) must be a power of
2234 two from 1 to 32 (or 64, if your platform supports that).
2236 =item Illegal octal digit %s
2238 (F) You used an 8 or 9 in an octal number.
2240 =item Illegal octal digit %s ignored
2242 (W digit) You may have tried to use an 8 or 9 in an octal number.
2243 Interpretation of the octal number stopped before the 8 or 9.
2245 =item Illegal switch in PERL5OPT: -%c
2247 (X) The PERL5OPT environment variable may only be used to set the
2248 following switches: B<-[CDIMUdmtw]>.
2250 =item Ill-formed CRTL environ value "%s"
2252 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
2253 internal environ array, and encountered an element without the C<=>
2254 delimiter used to separate keys from values. The element is ignored.
2256 =item Ill-formed message in prime_env_iter: |%s|
2258 (W internal) A warning peculiar to VMS. Perl tried to read a logical
2259 name or CLI symbol definition when preparing to iterate over %ENV, and
2260 didn't see the expected delimiter between key and value, so the line was
2263 =item (in cleanup) %s
2265 (W misc) This prefix usually indicates that a DESTROY() method raised
2266 the indicated exception. Since destructors are usually called by the
2267 system at arbitrary points during execution, and often a vast number of
2268 times, the warning is issued only once for any number of failures that
2269 would otherwise result in the same message being repeated.
2271 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2272 also result in this warning. See L<perlcall/G_KEEPERR>.
2274 =item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2277 (F) The method resolution order (MRO) of the given class is not
2278 C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2279 documentation in L<mro> for more information.
2281 =item In EBCDIC the v-string components cannot exceed 2147483647
2283 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2284 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2285 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2287 =item Infinite recursion in regex; marked by <-- HERE in m/%s/
2289 (F) You used a pattern that references itself without consuming any input
2290 text. You should check the pattern to ensure that recursive patterns
2291 either consume text or fail.
2293 The <-- HERE shows whereabouts in the regular expression the problem was
2296 =item Initialization of state variables in list context currently forbidden
2298 (F) Currently the implementation of "state" only permits the
2299 initialization of scalar variables in scalar context. Re-write
2300 C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2301 context. Constructions such as C<state (@a) = foo()> will be
2302 supported in a future perl release.
2304 =item Insecure dependency in %s
2306 (F) You tried to do something that the tainting mechanism didn't like.
2307 The tainting mechanism is turned on when you're running setuid or
2308 setgid, or when you specify B<-T> to turn it on explicitly. The
2309 tainting mechanism labels all data that's derived directly or indirectly
2310 from the user, who is considered to be unworthy of your trust. If any
2311 such data is used in a "dangerous" operation, you get this error. See
2312 L<perlsec> for more information.
2314 =item Insecure directory in %s
2316 (F) You can't use system(), exec(), or a piped open in a setuid or
2317 setgid script if C<$ENV{PATH}> contains a directory that is writable by
2318 the world. Also, the PATH must not contain any relative directory.
2321 =item Insecure $ENV{%s} while running %s
2323 (F) You can't use system(), exec(), or a piped open in a setuid or
2324 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
2325 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2326 supplied (or potentially supplied) by the user. The script must set
2327 the path to a known value, using trustworthy data. See L<perlsec>.
2329 =item Insecure user-defined property %s
2331 (F) Perl detected tainted data when trying to compile a regular
2332 expression that contains a call to a user-defined character property
2333 function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2334 See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2336 =item Integer overflow in format string for %s
2338 (F) The indexes and widths specified in the format string of C<printf()>
2339 or C<sprintf()> are too large. The numbers must not overflow the size of
2340 integers for your architecture.
2342 =item Integer overflow in %s number
2344 (S overflow) The hexadecimal, octal or binary number you have specified
2345 either as a literal or as an argument to hex() or oct() is too big for
2346 your architecture, and has been converted to a floating point number.
2347 On a 32-bit architecture the largest hexadecimal, octal or binary number
2348 representable without overflow is 0xFFFFFFFF, 037777777777, or
2349 0b11111111111111111111111111111111 respectively. Note that Perl
2350 transparently promotes all numbers to a floating point representation
2351 internally--subject to loss of precision errors in subsequent
2354 =item Integer overflow in srand
2356 (S overflow) The number you have passed to srand is too big to fit
2357 in your architecture's integer representation. The number has been
2358 replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2359 architectures). This means you may be getting less randomness than
2360 you expect, because different random seeds above the maximum will
2361 return the same sequence of random numbers.
2363 =item Integer overflow in version
2365 =item Integer overflow in version %d
2367 (W overflow) Some portion of a version initialization is too large for
2368 the size of integers for your architecture. This is not a warning
2369 because there is no rational reason for a version to try and use an
2370 element larger than typically 2**32. This is usually caused by trying
2371 to use some odd mathematical operation as a version, like 100/9.
2373 =item Internal disaster in regex; marked by <-- HERE in m/%s/
2375 (P) Something went badly wrong in the regular expression parser.
2376 The <-- HERE shows whereabouts in the regular expression the problem was
2379 =item Internal inconsistency in tracking vforks
2381 (S) A warning peculiar to VMS. Perl keeps track of the number of times
2382 you've called C<fork> and C<exec>, to determine whether the current call
2383 to C<exec> should affect the current script or a subprocess (see
2384 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2385 Perl is making a guess and treating this C<exec> as a request to
2386 terminate the Perl script and execute the specified command.
2388 =item Internal urp in regex; marked by <-- HERE in m/%s/
2390 (P) Something went badly awry in the regular expression parser. The
2391 <-- HERE shows whereabouts in the regular expression the problem was
2394 =item %s (...) interpreted as function
2396 (W syntax) You've run afoul of the rule that says that any list operator
2397 followed by parentheses turns into a function, with all the list
2398 operators arguments found inside the parentheses. See
2399 L<perlop/Terms and List Operators (Leftward)>.
2401 =item Invalid %s attribute: %s
2403 (F) The indicated attribute for a subroutine or variable was not recognized
2404 by Perl or by a user-supplied handler. See L<attributes>.
2406 =item Invalid %s attributes: %s
2408 (F) The indicated attributes for a subroutine or variable were not
2409 recognized by Perl or by a user-supplied handler. See L<attributes>.
2411 =item Invalid character in \N{...}; marked by <-- HERE in \N{%s}
2413 (F) Only certain characters are valid for character names. The
2414 indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2416 =item Invalid character in charnames alias definition; marked by <-- HERE in '%s
2418 (F) You tried to create a custom alias for a character name, with
2419 the C<:alias> option to C<use charnames> and the specified character in
2420 the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2422 =item Invalid conversion in %s: "%s"
2424 (W printf) Perl does not understand the given format conversion. See
2425 L<perlfunc/sprintf>.
2427 =item Invalid escape in the specified encoding in regex; marked by <-- HERE in
2430 (W regexp) The numeric escape (for example C<\xHH>) of value < 256
2431 didn't correspond to a single character through the conversion
2432 from the encoding specified by the encoding pragma.
2433 The escape was replaced with REPLACEMENT CHARACTER (U+FFFD) instead.
2434 The <-- HERE shows whereabouts in the regular expression the
2435 escape was discovered.
2437 =item Invalid hexadecimal number in \N{U+...}
2439 =item Invalid hexadecimal number in \N{U+...} in regex; marked by <-- HERE in
2442 (F) The character constant represented by C<...> is not a valid hexadecimal
2443 number. Either it is empty, or you tried to use a character other than
2444 0 - 9 or A - F, a - f in a hexadecimal number.
2446 =item Invalid module name %s with -%c option: contains single ':'
2448 (F) The module argument to perl's B<-m> and B<-M> command-line options
2449 cannot contain single colons in the module name, but only in the
2450 arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2451 B<-MFoo:Bar=baz> is not.
2453 =item Invalid mro name: '%s'
2455 (F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2456 where C<foo> is not a valid method resolution order (MRO). Currently,
2457 the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2458 a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2460 =item Invalid negative number (%s) in chr
2462 (W utf8) You passed a negative number to C<chr>. Negative numbers are
2463 not valid characters numbers, so it return the Unicode replacement
2466 =item invalid option -D%c, use -D'' to see choices
2468 (S debugging) Perl was called with invalid debugger flags. Call perl
2469 with the B<-D> option with no flags to see the list of acceptable values.
2470 See also L<perlrun/B<-D>I<letters>>.
2472 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
2474 (F) The range specified in a character class had a minimum character
2475 greater than the maximum character. One possibility is that you forgot the
2476 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
2477 up to C<ff>. The <-- HERE shows whereabouts in the regular expression the
2478 problem was discovered. See L<perlre>.
2480 =item Invalid range "%s" in transliteration operator
2482 (F) The range specified in the tr/// or y/// operator had a minimum
2483 character greater than the maximum character. See L<perlop>.
2485 =item Invalid separator character %s in attribute list
2487 (F) Something other than a colon or whitespace was seen between the
2488 elements of an attribute list. If the previous attribute had a
2489 parenthesised parameter list, perhaps that list was terminated too soon.
2492 =item Invalid separator character %s in PerlIO layer specification %s
2494 (W layer) When pushing layers onto the Perl I/O system, something other
2495 than a colon or whitespace was seen between the elements of a layer list.
2496 If the previous attribute had a parenthesised parameter list, perhaps that
2497 list was terminated too soon.
2499 =item Invalid strict version format (%s)
2501 (F) A version number did not meet the "strict" criteria for versions.
2502 A "strict" version number is a positive decimal number (integer or
2503 decimal-fraction) without exponentiation or else a dotted-decimal
2504 v-string with a leading 'v' character and at least three components.
2505 The parenthesized text indicates which criteria were not met.
2506 See the L<version> module for more details on allowed version formats.
2508 =item Invalid type '%s' in %s
2510 (F) The given character is not a valid pack or unpack type.
2511 See L<perlfunc/pack>.
2513 (W) The given character is not a valid pack or unpack type but used to be
2516 =item Invalid version format (%s)
2518 (F) A version number did not meet the "lax" criteria for versions.
2519 A "lax" version number is a positive decimal number (integer or
2520 decimal-fraction) without exponentiation or else a dotted-decimal
2521 v-string. If the v-string has fewer than three components, it
2522 must have a leading 'v' character. Otherwise, the leading 'v' is
2523 optional. Both decimal and dotted-decimal versions may have a
2524 trailing "alpha" component separated by an underscore character
2525 after a fractional or dotted-decimal component. The parenthesized
2526 text indicates which criteria were not met. See the L<version> module
2527 for more details on allowed version formats.
2529 =item Invalid version object
2531 (F) The internal structure of the version object was invalid.
2532 Perhaps the internals were modified directly in some way or
2533 an arbitrary reference was blessed into the "version" class.
2535 =item ioctl is not implemented
2537 (F) Your machine apparently doesn't implement ioctl(), which is pretty
2538 strange for a machine that supports C.
2540 =item ioctl() on unopened %s
2542 (W unopened) You tried ioctl() on a filehandle that was never opened.
2543 Check your control flow and number of arguments.
2545 =item IO layers (like '%s') unavailable
2547 (F) Your Perl has not been configured to have PerlIO, and therefore
2548 you cannot use IO layers. To have PerlIO, Perl must be configured
2551 =item IO::Socket::atmark not implemented on this architecture
2553 (F) Your machine doesn't implement the sockatmark() functionality,
2554 neither as a system call nor an ioctl call (SIOCATMARK).
2556 =item $* is no longer supported
2558 (D deprecated, syntax) The special variable C<$*>, deprecated in older
2559 perls, has been removed as of 5.9.0 and is no longer supported. In
2560 previous versions of perl the use of C<$*> enabled or disabled multi-line
2561 matching within a string.
2563 Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
2564 modifiers. You can enable C</m> for a lexical scope (even a whole file)
2565 with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
2566 then all regular expressions behaved as if they were written using C</m>.)
2568 =item $# is no longer supported
2570 (D deprecated, syntax) The special variable C<$#>, deprecated in older
2571 perls, has been removed as of 5.9.3 and is no longer supported. You
2572 should use the printf/sprintf functions instead.
2574 =item '%s' is not a code reference
2576 (W overload) The second (fourth, sixth, ...) argument of
2577 overload::constant needs to be a code reference. Either
2578 an anonymous subroutine, or a reference to a subroutine.
2580 =item '%s' is not an overloadable type
2582 (W overload) You tried to overload a constant type the overload package is
2585 =item Junk on end of regexp in regex m/%s/
2587 (P) The regular expression parser is confused.
2589 =item Label not found for "last %s"
2591 (F) You named a loop to break out of, but you're not currently in a loop
2592 of that name, not even if you count where you were called from. See
2595 =item Label not found for "next %s"
2597 (F) You named a loop to continue, but you're not currently in a loop of
2598 that name, not even if you count where you were called from. See
2601 =item Label not found for "redo %s"
2603 (F) You named a loop to restart, but you're not currently in a loop of
2604 that name, not even if you count where you were called from. See
2607 =item leaving effective %s failed
2609 (F) While under the C<use filetest> pragma, switching the real and
2610 effective uids or gids failed.
2612 =item length/code after end of string in unpack
2614 (F) While unpacking, the string buffer was already used up when an unpack
2615 length/code combination tried to obtain more data. This results in
2616 an undefined value for the length. See L<perlfunc/pack>.
2618 =item length() used on %s
2620 (W syntax) You used length() on either an array or a hash when you
2621 probably wanted a count of the items.
2623 Array size can be obtained by doing:
2627 The number of items in a hash can be obtained by doing:
2631 =item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2633 (F) An extension is attempting to insert text into the current parse
2634 (using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2635 couldn't be part of the current input. This is an inherent pitfall
2636 of the stuffing mechanism, and one of the reasons to avoid it. Where
2637 it is necessary to stuff, stuffing only plain ASCII is recommended.
2639 =item Lexing code internal error (%s)
2641 (F) Lexing code supplied by an extension violated the lexer's API in a
2644 =item listen() on closed socket %s
2646 (W closed) You tried to do a listen on a closed socket. Did you forget
2647 to check the return value of your socket() call? See
2650 =item List form of piped open not implemented
2652 (F) On some platforms, notably Windows, the three-or-more-arguments
2653 form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2654 Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2656 =item localtime(%f) too large
2658 (W overflow) You called C<localtime> with a number that was larger
2659 than it can reliably handle and C<localtime> probably returned the
2660 wrong date. This warning is also triggered with NaN (the special
2661 not-a-number value).
2663 =item localtime(%f) too small
2665 (W overflow) You called C<localtime> with a number that was smaller
2666 than it can reliably handle and C<localtime> probably returned the
2669 =item Lookbehind longer than %d not implemented in regex m/%s/
2671 (F) There is currently a limit on the length of string which lookbehind can
2672 handle. This restriction may be eased in a future release.
2674 =item Lost precision when %s %f by 1
2676 (W imprecision) The value you attempted to increment or decrement by one
2677 is too large for the underlying floating point representation to store
2678 accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2679 warning because it has already switched from integers to floating point
2680 when values are too large for integers, and now even floating point is
2681 insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
2683 =item lstat() on filehandle%s
2685 (W io) You tried to do an lstat on a filehandle. What did you mean
2686 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2687 instead on the filehandle.)
2689 =item lvalue attribute %s already-defined subroutine
2691 (W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2692 attribute on or off on a Perl subroutine that is already defined
2693 does not always work properly. It may or may not do what you
2694 want, depending on what code is inside the subroutine, with exact
2695 details subject to change between Perl versions. Only do this
2696 if you really know what you are doing.
2698 =item lvalue attribute ignored after the subroutine has been defined
2700 (W misc) Using the C<:lvalue> declarative syntax to make a Perl
2701 subroutine an lvalue subroutine after it has been defined is
2702 not permitted. To make the subroutine an lvalue subroutine,
2703 add the lvalue attribute to the definition, or put the C<sub
2704 foo :lvalue;> declaration before the definition.
2706 See also L<attributes.pm|attributes>.
2708 =item Malformed integer in [] in pack
2710 (F) Between the brackets enclosing a numeric repeat count only digits
2711 are permitted. See L<perlfunc/pack>.
2713 =item Malformed integer in [] in unpack
2715 (F) Between the brackets enclosing a numeric repeat count only digits
2716 are permitted. See L<perlfunc/pack>.
2718 =item Malformed PERLLIB_PREFIX
2720 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2727 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2728 a builtin library search path, prefix2 is substituted. The error may
2729 appear if components are not found, or are too long. See
2730 "PERLLIB_PREFIX" in L<perlos2>.
2732 =item Malformed prototype for %s: %s
2734 (F) You tried to use a function with a malformed prototype. The
2735 syntax of function prototypes is given a brief compile-time check for
2736 obvious errors like invalid characters. A more rigorous check is run
2737 when the function is called.
2739 =item Malformed UTF-8 character (%s)
2741 (S utf8)(F) Perl detected a string that didn't comply with UTF-8
2742 encoding rules, even though it had the UTF8 flag on.
2744 One possible cause is that you set the UTF8 flag yourself for data that
2745 you thought to be in UTF-8 but it wasn't (it was for example legacy
2746 8-bit data). To guard against this, you can use Encode::decode_utf8.
2748 If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2749 sequences are handled gracefully, but if you use C<:utf8>, the flag is
2750 set without validating the data, possibly resulting in this error
2753 See also L<Encode/"Handling Malformed Data">.
2755 =item Malformed UTF-8 character immediately after '%s'
2757 (F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2758 encoding rules. The message prints out the properly encoded characters
2759 just before the first bad one. If C<utf8> warnings are enabled, a
2760 warning is generated that gives more details about the type of
2763 =item Malformed UTF-8 returned by \N{%s} immediately after '%s'
2765 (F) The charnames handler returned malformed UTF-8.
2767 =item Malformed UTF-8 string in '%c' format in unpack
2769 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2770 rules and perl was unable to guess how to make more progress.
2772 =item Malformed UTF-8 string in pack
2774 (F) You tried to pack something that didn't comply with UTF-8 encoding
2775 rules and perl was unable to guess how to make more progress.
2777 =item Malformed UTF-8 string in unpack
2779 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2780 rules and perl was unable to guess how to make more progress.
2782 =item Malformed UTF-16 surrogate
2784 (F) Perl thought it was reading UTF-16 encoded character data but while
2785 doing it Perl met a malformed Unicode surrogate.
2787 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2789 (W regexp) The pattern you've specified would be an infinite loop if the
2790 regular expression engine didn't specifically check for that. The <-- HERE
2791 shows whereabouts in the regular expression the problem was discovered.
2794 =item Maximal count of pending signals (%u) exceeded
2796 (F) Perl aborted due to too high a number of signals pending. This
2797 usually indicates that your operating system tried to deliver signals
2798 too fast (with a very high priority), starving the perl process from
2799 resources it would need to reach a point where it can process signals
2800 safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2802 =item "%s" may clash with future reserved word
2804 (W) This warning may be due to running a perl5 script through a perl4
2805 interpreter, especially if the word that is being warned about is
2808 =item '%' may not be used in pack
2810 (F) You can't pack a string by supplying a checksum, because the
2811 checksumming process loses information, and you can't go the other way.
2812 See L<perlfunc/unpack>.
2814 =item Method for operation %s not found in package %s during blessing
2816 (F) An attempt was made to specify an entry in an overloading table that
2817 doesn't resolve to a valid subroutine. See L<overload>.
2819 =item Method %s not permitted
2823 =item Might be a runaway multi-line %s string starting on line %d
2825 (S) An advisory indicating that the previous error may have been caused
2826 by a missing delimiter on a string or pattern, because it eventually
2827 ended earlier on the current line.
2829 =item Misplaced _ in number
2831 (W syntax) An underscore (underbar) in a numeric constant did not
2832 separate two digits.
2834 =item Missing argument in %s
2836 (W uninitialized) A printf-type format required more arguments than were
2839 =item Missing argument to -%c
2841 (F) The argument to the indicated command line switch must follow
2842 immediately after the switch, without intervening spaces.
2844 =item Missing braces on \N{}
2846 =item Missing braces on \N{} in regex; marked by <-- HERE in m/%s/
2848 (F) Wrong syntax of character name literal C<\N{charname}> within
2849 double-quotish context. This can also happen when there is a space
2850 (or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
2851 This modifier does not change the requirement that the brace immediately
2854 =item Missing braces on \o{}
2856 (F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
2858 =item Missing comma after first argument to %s function
2860 (F) While certain functions allow you to specify a filehandle or an
2861 "indirect object" before the argument list, this ain't one of them.
2863 =item Missing command in piped open
2865 (W pipe) You used the C<open(FH, "| command")> or
2866 C<open(FH, "command |")> construction, but the command was missing or
2869 =item Missing control char name in \c
2871 (F) A double-quoted string ended with "\c", without the required control
2874 =item Missing name in "%s sub"
2876 (F) The reserved syntax for lexically scoped subroutines requires that
2877 they have a name with which they can be found.
2879 =item Missing $ on loop variable
2881 (F) Apparently you've been programming in B<csh> too much. Variables
2882 are always mentioned with the $ in Perl, unlike in the shells, where it
2883 can vary from one line to the next.
2885 =item (Missing operator before %s?)
2887 (S syntax) This is an educated guess made in conjunction with the message
2888 "%s found where operator expected". Often the missing operator is a comma.
2890 =item Missing right brace on \%c{} in regex; marked by <-- HERE in m/%s/
2892 (F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
2894 =item Missing right brace on \N{} or unescaped left brace after \N
2896 (F) C<\N> has two meanings.
2898 The traditional one has it followed by a name enclosed in braces,
2899 meaning the character (or sequence of characters) given by that
2900 name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
2901 double-quoted strings and regular expression patterns. In patterns,
2902 it doesn't have the meaning an unescaped C<*> does.
2904 Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
2905 in patterns, namely to match a non-newline character. (This is short
2906 for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
2908 This can lead to some ambiguities. When C<\N> is not followed immediately
2909 by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
2910 form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
2911 means to match the given quantity of non-newlines (in these examples,
2912 3; and 5 or more, respectively). In all other case, where there is a
2913 C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
2915 However, if there is no matching C<}>, Perl doesn't know if it was
2916 mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
2917 If you meant the former, add the right brace; if you meant the latter,
2918 escape the brace with a backslash, like so: C<\N\{>
2920 =item Missing right curly or square bracket
2922 (F) The lexer counted more opening curly or square brackets than closing
2923 ones. As a general rule, you'll find it's missing near the place you
2926 =item (Missing semicolon on previous line?)
2928 (S syntax) This is an educated guess made in conjunction with the message
2929 "%s found where operator expected". Don't automatically put a semicolon on
2930 the previous line just because you saw this message.
2932 =item Modification of a read-only value attempted
2934 (F) You tried, directly or indirectly, to change the value of a
2935 constant. You didn't, of course, try "2 = 1", because the compiler
2936 catches that. But an easy way to do the same thing is:
2938 sub mod { $_[0] = 1 }
2941 Another way is to assign to a substr() that's off the end of the string.
2943 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2944 is aliased to a constant in the look I<LIST>:
2947 foreach my $n ($x, 2) {
2948 $n *= 2; # modifies the $x, but fails on attempt to
2951 =item Modification of non-creatable array value attempted, %s
2953 (F) You tried to make an array value spring into existence, and the
2954 subscript was probably negative, even counting from end of the array
2957 =item Modification of non-creatable hash value attempted, %s
2959 (P) You tried to make a hash value spring into existence, and it
2960 couldn't be created for some peculiar reason.
2962 =item Module name must be constant
2964 (F) Only a bare module name is allowed as the first argument to a "use".
2966 =item Module name required with -%c option
2968 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2969 you omitted the name of the module. Consult L<perlrun> for full details
2970 about C<-M> and C<-m>.
2972 =item More than one argument to '%s' open
2974 (F) The C<open> function has been asked to open multiple files. This
2975 can happen if you are trying to open a pipe to a command that takes a
2976 list of arguments, but have forgotten to specify a piped open mode.
2977 See L<perlfunc/open> for details.
2979 =item msg%s not implemented
2981 (F) You don't have System V message IPC on your system.
2983 =item Multidimensional syntax %s not supported
2985 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2986 They're written like C<$foo[1][2][3]>, as in C.
2988 =item '/' must follow a numeric type in unpack
2990 (F) You had an unpack template that contained a '/', but this did not
2991 follow some unpack specification producing a numeric value.
2992 See L<perlfunc/pack>.
2994 =item "my sub" not yet implemented
2996 (F) Lexically scoped subroutines are not yet implemented. Don't try
2999 =item "my" variable %s can't be in a package
3001 (F) Lexically scoped variables aren't in a package, so it doesn't make
3002 sense to try to declare one with a package qualifier on the front. Use
3003 local() if you want to localize a package variable.
3005 =item Name "%s::%s" used only once: possible typo
3007 (W once) Typographical errors often show up as unique variable names.
3008 If you had a good reason for having a unique name, then just mention it
3009 again somehow to suppress the message. The C<our> declaration is
3010 provided for this purpose.
3012 NOTE: This warning detects symbols that have been used only once so $c, @c,
3013 %c, *c, &c, sub c{}, c(), and c (the filehandle or format) are considered
3014 the same; if a program uses $c only once but also uses any of the others it
3015 will not trigger this warning.
3017 =item \N in a character class must be a named character: \N{...} in regex;
3018 marked by <-- HERE in m/%s/
3020 (F) The new (5.12) meaning of C<\N> as C<[^\n]> is not valid in a bracketed
3021 character class, for the same reason that C<.> in a character class loses
3022 its specialness: it matches almost everything, which is probably not
3025 =item \N{NAME} must be resolved by the lexer in regex; marked by <-- HERE in m/%s/
3027 (F) When compiling a regex pattern, an unresolved named character or
3028 sequence was encountered. This can happen in any of several ways that
3029 bypass the lexer, such as using single-quotish context, or an extra
3030 backslash in double-quotish:
3032 $re = '\N{SPACE}'; # Wrong!
3033 $re = "\\N{SPACE}"; # Wrong!
3036 Instead, use double-quotes with a single backslash:
3038 $re = "\N{SPACE}"; # ok
3041 The lexer can be bypassed as well by creating the pattern from smaller
3045 /${re}{SPACE}/; # Wrong!
3047 It's not a good idea to split a construct in the middle like this, and it
3048 doesn't work here. Instead use the solution above.
3050 Finally, the message also can happen under the C</x> regex modifier when the
3051 C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
3053 /\N {SPACE}/x; # Wrong!
3056 =item Negative '/' count in unpack
3058 (F) The length count obtained from a length/code unpack operation was
3059 negative. See L<perlfunc/pack>.
3061 =item Negative length
3063 (F) You tried to do a read/write/send/recv operation with a buffer
3064 length that is less than 0. This is difficult to imagine.
3066 =item Negative offset to vec in lvalue context
3068 (F) When C<vec> is called in an lvalue context, the second argument must be
3069 greater than or equal to zero.
3071 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
3073 (F) You can't quantify a quantifier without intervening parentheses.
3074 So things like ** or +* or ?* are illegal. The <-- HERE shows
3075 whereabouts in the regular expression the problem was discovered.
3077 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
3078 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
3080 =item %s never introduced
3082 (S internal) The symbol in question was declared but somehow went out of
3083 scope before it could possibly have been used.
3085 =item next::method/next::can/maybe::next::method cannot find enclosing method
3087 (F) C<next::method> needs to be called within the context of a
3088 real method in a real package, and it could not find such a context.
3091 =item No %s allowed while running setuid
3093 (F) Certain operations are deemed to be too insecure for a setuid or
3094 setgid script to even be allowed to attempt. Generally speaking there
3095 will be another way to do what you want that is, if not secure, at least
3096 securable. See L<perlsec>.
3098 =item No code specified for -%c
3100 (F) Perl's B<-e> and B<-E> command-line options require an argument. If
3101 you want to run an empty program, pass the empty string as a separate
3102 argument or run a program consisting of a single 0 or 1:
3108 =item No comma allowed after %s
3110 (F) A list operator that has a filehandle or "indirect object" is
3111 not allowed to have a comma between that and the following arguments.
3112 Otherwise it'd be just another one of the arguments.
3114 One possible cause for this is that you expected to have imported
3115 a constant to your name space with B<use> or B<import> while no such
3116 importing took place, it may for example be that your operating
3117 system does not support that particular constant. Hopefully you did
3118 use an explicit import list for the constants you expect to see;
3119 please see L<perlfunc/use> and L<perlfunc/import>. While an
3120 explicit import list would probably have caught this error earlier
3121 it naturally does not remedy the fact that your operating system
3122 still does not support that constant. Maybe you have a typo in
3123 the constants of the symbol import list of B<use> or B<import> or in the
3124 constant name at the line where this error was triggered?
3126 =item No command into which to pipe on command line
3128 (F) An error peculiar to VMS. Perl handles its own command line
3129 redirection, and found a '|' at the end of the command line, so it
3130 doesn't know where you want to pipe the output from this command.
3132 =item No DB::DB routine defined
3134 (F) The currently executing code was compiled with the B<-d> switch, but
3135 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3136 module) didn't define a routine to be called at the beginning of each
3139 =item No dbm on this machine
3141 (P) This is counted as an internal error, because every machine should
3142 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
3144 =item No DB::sub routine defined
3146 (F) The currently executing code was compiled with the B<-d> switch, but
3147 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
3148 module) didn't define a C<DB::sub> routine to be called at the beginning
3149 of each ordinary subroutine call.
3151 =item No directory specified for -I
3153 (F) The B<-I> command-line switch requires a directory name as part of the
3154 I<same> argument. Use B<-Ilib>, for instance. B<-I lib> won't work.
3156 =item No error file after 2> or 2>> on command line
3158 (F) An error peculiar to VMS. Perl handles its own command line
3159 redirection, and found a '2>' or a '2>>' on the command line, but can't
3160 find the name of the file to which to write data destined for stderr.
3162 =item No group ending character '%c' found in template
3164 (F) A pack or unpack template has an opening '(' or '[' without its
3165 matching counterpart. See L<perlfunc/pack>.
3167 =item No input file after < on command line
3169 (F) An error peculiar to VMS. Perl handles its own command line
3170 redirection, and found a '<' on the command line, but can't find the
3171 name of the file from which to read data for stdin.
3173 =item No next::method '%s' found for %s
3175 (F) C<next::method> found no further instances of this method name
3176 in the remaining packages of the MRO of this class. If you don't want
3177 it throwing an exception, use C<maybe::next::method>
3178 or C<next::can>. See L<mro>.
3180 =item "no" not allowed in expression
3182 (F) The "no" keyword is recognized and executed at compile time, and
3183 returns no useful value. See L<perlmod>.
3185 =item No output file after > on command line
3187 (F) An error peculiar to VMS. Perl handles its own command line
3188 redirection, and found a lone '>' at the end of the command line, so it
3189 doesn't know where you wanted to redirect stdout.
3191 =item No output file after > or >> on command line
3193 (F) An error peculiar to VMS. Perl handles its own command line
3194 redirection, and found a '>' or a '>>' on the command line, but can't
3195 find the name of the file to which to write data destined for stdout.
3197 =item No package name allowed for variable %s in "our"
3199 (F) Fully qualified variable names are not allowed in "our"
3200 declarations, because that doesn't make much sense under existing
3201 semantics. Such syntax is reserved for future extensions.
3203 =item No Perl script found in input
3205 (F) You called C<perl -x>, but no line was found in the file beginning
3206 with #! and containing the word "perl".
3208 =item No setregid available
3210 (F) Configure didn't find anything resembling the setregid() call for
3213 =item No setreuid available
3215 (F) Configure didn't find anything resembling the setreuid() call for
3218 =item No such class field "%s" in variable %s of type %s
3220 (F) You tried to access a key from a hash through the indicated typed
3221 variable but that key is not allowed by the package of the same type.
3222 The indicated package has restricted the set of allowed keys using the
3225 =item No such class %s
3227 (F) You provided a class qualifier in a "my", "our" or "state"
3228 declaration, but this class doesn't exist at this point in your program.
3230 =item No such hook: %s
3232 (F) You specified a signal hook that was not recognized by Perl.
3233 Currently, Perl accepts C<__DIE__> and C<__WARN__> as valid signal hooks.
3235 =item No such pipe open
3237 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
3238 close a pipe which hadn't been opened. This should have been caught
3239 earlier as an attempt to close an unopened filehandle.
3241 =item No such signal: SIG%s
3243 (W signal) You specified a signal name as a subscript to %SIG that was
3244 not recognized. Say C<kill -l> in your shell to see the valid signal
3245 names on your system.
3247 =item Not a CODE reference
3249 (F) Perl was trying to evaluate a reference to a code value (that is, a
3250 subroutine), but found a reference to something else instead. You can
3251 use the ref() function to find out what kind of ref it really was. See
3254 =item Not a GLOB reference
3256 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
3257 symbol table entry that looks like C<*foo>), but found a reference to
3258 something else instead. You can use the ref() function to find out what
3259 kind of ref it really was. See L<perlref>.
3261 =item Not a HASH reference
3263 (F) Perl was trying to evaluate a reference to a hash value, but found a
3264 reference to something else instead. You can use the ref() function to
3265 find out what kind of ref it really was. See L<perlref>.
3267 =item Not an ARRAY reference
3269 (F) Perl was trying to evaluate a reference to an array value, but found
3270 a reference to something else instead. You can use the ref() function
3271 to find out what kind of ref it really was. See L<perlref>.
3273 =item Not an unblessed ARRAY reference
3275 (F) You passed a reference to a blessed array to C<push>, C<shift> or
3276 another array function. These only accept unblessed array references
3277 or arrays beginning explicitly with C<@>.
3279 =item Not a SCALAR reference
3281 (F) Perl was trying to evaluate a reference to a scalar value, but found
3282 a reference to something else instead. You can use the ref() function
3283 to find out what kind of ref it really was. See L<perlref>.
3285 =item Not a subroutine reference
3287 (F) Perl was trying to evaluate a reference to a code value (that is, a
3288 subroutine), but found a reference to something else instead. You can
3289 use the ref() function to find out what kind of ref it really was. See
3292 =item Not a subroutine reference in overload table
3294 (F) An attempt was made to specify an entry in an overloading table that
3295 doesn't somehow point to a valid subroutine. See L<overload>.
3297 =item Not enough arguments for %s
3299 (F) The function requires more arguments than you specified.
3301 =item Not enough format arguments
3303 (W syntax) A format specified more picture fields than the next line
3304 supplied. See L<perlform>.
3308 (A) You've accidentally run your script through the Bourne shell instead
3309 of Perl. Check the #! line, or manually feed your script into Perl
3312 =item no UTC offset information; assuming local time is UTC
3314 (S) A warning peculiar to VMS. Perl was unable to find the local
3315 timezone offset, so it's assuming that local system time is equivalent
3316 to UTC. If it's not, define the logical name
3317 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
3318 need to be added to UTC to get local time.
3320 =item Non-octal character '%c'. Resolved as "%s"
3322 (W digit) In parsing an octal numeric constant, a character was
3323 unexpectedly encountered that isn't octal. The resulting value
3326 =item Non-string passed as bitmask
3328 (W misc) A number has been passed as a bitmask argument to select().
3329 Use the vec() function to construct the file descriptor bitmasks for
3330 select. See L<perlfunc/select>.
3332 =item Null filename used
3334 (F) You can't require the null filename, especially because on many
3335 machines that means the current directory! See L<perlfunc/require>.
3337 =item NULL OP IN RUN
3339 (S debugging) Some internal routine called run() with a null opcode
3342 =item Null picture in formline
3344 (F) The first argument to formline must be a valid format picture
3345 specification. It was found to be empty, which probably means you
3346 supplied it an uninitialized value. See L<perlform>.
3350 (P) An attempt was made to realloc NULL.
3352 =item NULL regexp argument
3354 (P) The internal pattern matching routines blew it big time.
3356 =item NULL regexp parameter
3358 (P) The internal pattern matching routines are out of their gourd.
3360 =item Number too long
3362 (F) Perl limits the representation of decimal numbers in programs to
3363 about 250 characters. You've exceeded that length. Future
3364 versions of Perl are likely to eliminate this arbitrary limitation. In
3365 the meantime, try using scientific notation (e.g. "1e6" instead of
3368 =item Number with no digits
3370 (F) Perl was looking for a number but found nothing that looked like
3371 a number. This happens, for example with C<\o{}>, with no number between
3374 =item "my %s" used in sort comparison
3376 (W syntax) The package variables $a and $b are used for sort comparisons.
3377 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3378 sort comparison block, and the variable had earlier been declared as a
3379 lexical variable. Either qualify the sort variable with the package
3380 name, or rename the lexical variable.
3382 =item Octal number > 037777777777 non-portable
3384 (W portable) The octal number you specified is larger than 2**32-1
3385 (4294967295) and therefore non-portable between systems. See
3386 L<perlport> for more on portability concerns.
3388 =item Odd number of arguments for overload::constant
3390 (W overload) The call to overload::constant contained an odd number of
3391 arguments. The arguments should come in pairs.
3393 =item Odd number of elements in anonymous hash
3395 (W misc) You specified an odd number of elements to initialize a hash,
3396 which is odd, because hashes come in key/value pairs.
3398 =item Odd number of elements in hash assignment
3400 (W misc) You specified an odd number of elements to initialize a hash,
3401 which is odd, because hashes come in key/value pairs.
3403 =item Offset outside string
3405 (F)(W layer) You tried to do a read/write/send/recv/seek operation
3406 with an offset pointing outside the buffer. This is difficult to
3407 imagine. The sole exceptions to this are that zero padding will
3408 take place when going past the end of the string when either
3409 C<sysread()>ing a file, or when seeking past the end of a scalar opened
3410 for I/O (in anticipation of future reads and to imitate the behaviour
3413 =item %s() on unopened %s
3415 (W unopened) An I/O operation was attempted on a filehandle that was
3416 never initialized. You need to do an open(), a sysopen(), or a socket()
3417 call, or call a constructor from the FileHandle package.
3419 =item -%s on unopened filehandle %s
3421 (W unopened) You tried to invoke a file test operator on a filehandle
3422 that isn't open. Check your control flow. See also L<perlfunc/-X>.
3424 =item Strings with code points over 0xFF may not be mapped into in-memory file handles
3426 (W utf8) You tried to open a reference to a scalar for read or append
3427 where the scalar contained code points over 0xFF. In-memory files
3428 model on-disk files and can only contain bytes.
3432 (S internal) An internal warning that the grammar is screwed up.
3436 (S internal) An internal warning that the grammar is screwed up.
3438 =item Opening dirhandle %s also as a file
3440 (D io, deprecated) You used open() to associate a filehandle to
3441 a symbol (glob or scalar) that already holds a dirhandle.
3442 Although legal, this idiom might render your code confusing
3445 =item Opening filehandle %s also as a directory
3447 (D io, deprecated) You used opendir() to associate a dirhandle to
3448 a symbol (glob or scalar) that already holds a filehandle.
3449 Although legal, this idiom might render your code confusing
3452 =item Operation "%s": no method found, %s
3454 (F) An attempt was made to perform an overloaded operation for which no
3455 handler was defined. While some handlers can be autogenerated in terms
3456 of other handlers, there is no default handler for any operation, unless
3457 the C<fallback> overloading key is specified to be true. See L<overload>.
3459 =item Operation "%s" returns its argument for non-Unicode code point 0x%X
3461 (S utf8, non_unicode) You performed an operation requiring Unicode
3462 semantics on a code point that is not in Unicode, so what it should do
3463 is not defined. Perl has chosen to have it do nothing, and warn you.
3465 If the operation shown is "ToFold", it means that case-insensitive
3466 matching in a regular expression was done on the code point.
3468 If you know what you are doing you can turn off this warning by
3469 C<no warnings 'non_unicode';>.
3471 =item Operation "%s" returns its argument for UTF-16 surrogate U+%X
3473 (S utf8, surrogate) You performed an operation requiring Unicode
3474 semantics on a Unicode surrogate. Unicode frowns upon the use of
3475 surrogates for anything but storing strings in UTF-16, but semantics
3476 are (reluctantly) defined for the surrogates, and they are to do
3477 nothing for this operation. Because the use of surrogates can be
3478 dangerous, Perl warns.
3480 If the operation shown is "ToFold", it means that case-insensitive
3481 matching in a regular expression was done on the code point.
3483 If you know what you are doing you can turn off this warning by
3484 C<no warnings 'surrogate';>.
3486 =item Operator or semicolon missing before %s
3488 (S ambiguous) You used a variable or subroutine call where the parser
3489 was expecting an operator. The parser has assumed you really meant to
3490 use an operator, but this is highly likely to be incorrect. For
3491 example, if you say "*foo *foo" it will be interpreted as if you said
3494 =item "our" variable %s redeclared
3496 (W misc) You seem to have already declared the same global once before
3497 in the current lexical scope.
3499 =item Out of memory!
3501 (X) The malloc() function returned 0, indicating there was insufficient
3502 remaining memory (or virtual memory) to satisfy the request. Perl has
3503 no option but to exit immediately.
3505 At least in Unix you may be able to get past this by increasing your
3506 process datasize limits: in csh/tcsh use C<limit> and
3507 C<limit datasize n> (where C<n> is the number of kilobytes) to check
3508 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
3509 and C<ulimit -d n>, respectively.
3511 =item Out of memory during %s extend
3513 (X) An attempt was made to extend an array, a list, or a string beyond
3514 the largest possible memory allocation.
3516 =item Out of memory during "large" request for %s
3518 (F) The malloc() function returned 0, indicating there was insufficient
3519 remaining memory (or virtual memory) to satisfy the request. However,
3520 the request was judged large enough (compile-time default is 64K), so a
3521 possibility to shut down by trapping this error is granted.
3523 =item Out of memory during request for %s
3525 (X)(F) The malloc() function returned 0, indicating there was
3526 insufficient remaining memory (or virtual memory) to satisfy the
3529 The request was judged to be small, so the possibility to trap it
3530 depends on the way perl was compiled. By default it is not trappable.
3531 However, if compiled for this, Perl may use the contents of C<$^M> as an
3532 emergency pool after die()ing with this message. In this case the error
3533 is trappable I<once>, and the error message will include the line and file
3534 where the failed request happened.
3536 =item Out of memory during ridiculously large request
3538 (F) You can't allocate more than 2^31+"small amount" bytes. This error
3539 is most likely to be caused by a typo in the Perl program. e.g.,
3540 C<$arr[time]> instead of C<$arr[$time]>.
3542 =item Out of memory for yacc stack
3544 (F) The yacc parser wanted to grow its stack so it could continue
3545 parsing, but realloc() wouldn't give it more memory, virtual or
3548 =item '.' outside of string in pack
3550 (F) The argument to a '.' in your template tried to move the working
3551 position to before the start of the packed string being built.
3553 =item '@' outside of string in unpack
3555 (F) You had a template that specified an absolute position outside
3556 the string being unpacked. See L<perlfunc/pack>.
3558 =item '@' outside of string with malformed UTF-8 in unpack
3560 (F) You had a template that specified an absolute position outside
3561 the string being unpacked. The string being unpacked was also invalid
3562 UTF-8. See L<perlfunc/pack>.
3564 =item overload arg '%s' is invalid
3566 (W overload) The L<overload> pragma was passed an argument it did not
3567 recognize. Did you mistype an operator?
3569 =item Overloaded dereference did not return a reference
3571 (F) An object with an overloaded dereference operator was dereferenced,
3572 but the overloaded operation did not return a reference. See
3575 =item Overloaded qr did not return a REGEXP
3577 (F) An object with a C<qr> overload was used as part of a match, but the
3578 overloaded operation didn't return a compiled regexp. See L<overload>.
3580 =item %s package attribute may clash with future reserved word: %s
3582 (W reserved) A lowercase attribute name was used that had a
3583 package-specific handler. That name might have a meaning to Perl itself
3584 some day, even though it doesn't yet. Perhaps you should use a
3585 mixed-case attribute name, instead. See L<attributes>.
3587 =item pack/unpack repeat count overflow
3589 (F) You can't specify a repeat count so large that it overflows your
3590 signed integers. See L<perlfunc/pack>.
3594 (W io) A single call to write() produced more lines than can fit on a
3595 page. See L<perlform>.
3599 (P) An internal error.
3601 =item panic: attempt to call %s in %s
3603 (P) One of the file test operators entered a code branch that calls
3604 an ACL related-function, but that function is not available on this
3605 platform. Earlier checks mean that it should not be possible to
3606 enter this branch on this platform.
3608 =item panic: child pseudo-process was never scheduled
3610 (P) A child pseudo-process in the ithreads implementation on Windows
3611 was not scheduled within the time period allowed and therefore was not
3612 able to initialize properly.
3614 =item panic: ck_grep, type=%u
3616 (P) Failed an internal consistency check trying to compile a grep.
3618 =item panic: ck_split, type=%u
3620 (P) Failed an internal consistency check trying to compile a split.
3622 =item panic: corrupt saved stack index %ld
3624 (P) The savestack was requested to restore more localized values than
3625 there are in the savestack.
3627 =item panic: del_backref
3629 (P) Failed an internal consistency check while trying to reset a weak
3634 (P) We popped the context stack to an eval context, and then discovered
3635 it wasn't an eval context.
3637 =item panic: do_subst
3639 (P) The internal pp_subst() routine was called with invalid operational
3642 =item panic: do_trans_%s
3644 (P) The internal do_trans routines were called with invalid operational
3647 =item panic: fold_constants JMPENV_PUSH returned %d
3649 (P) While attempting folding constants an exception other than an C<eval>
3654 (P) The library function frexp() failed, making printf("%f") impossible.
3656 =item panic: goto, type=%u, ix=%ld
3658 (P) We popped the context stack to a context with the specified label,
3659 and then discovered it wasn't a context we know how to do a goto in.
3661 =item panic: gp_free failed to free glob pointer
3663 (P) The internal routine used to clear a typeglob's entries tried
3664 repeatedly, but each time something re-created entries in the glob.
3665 Most likely the glob contains an object with a reference back to
3666 the glob and a destructor that adds a new object to the glob.
3668 =item panic: INTERPCASEMOD, %s
3670 (P) The lexer got into a bad state at a case modifier.
3672 =item panic: INTERPCONCAT, %s
3674 (P) The lexer got into a bad state parsing a string with brackets.
3676 =item panic: kid popen errno read
3678 (F) forked child returned an incomprehensible message about its errno.
3680 =item panic: last, type=%u
3682 (P) We popped the context stack to a block context, and then discovered
3683 it wasn't a block context.
3685 =item panic: leave_scope clearsv
3687 (P) A writable lexical variable became read-only somehow within the
3690 =item panic: leave_scope inconsistency %u
3692 (P) The savestack probably got out of sync. At least, there was an
3693 invalid enum on the top of it.
3695 =item panic: magic_killbackrefs
3697 (P) Failed an internal consistency check while trying to reset all weak
3698 references to an object.
3700 =item panic: malloc, %s
3702 (P) Something requested a negative number of bytes of malloc.
3704 =item panic: memory wrap
3706 (P) Something tried to allocate more memory than possible.
3708 =item panic: pad_alloc, %p!=%p
3710 (P) The compiler got confused about which scratch pad it was allocating
3711 and freeing temporaries and lexicals from.
3713 =item panic: pad_free curpad, %p!=%p
3715 (P) The compiler got confused about which scratch pad it was allocating
3716 and freeing temporaries and lexicals from.
3718 =item panic: pad_free po
3720 (P) An invalid scratch pad offset was detected internally.
3722 =item panic: pad_reset curpad, %p!=%p
3724 (P) The compiler got confused about which scratch pad it was allocating
3725 and freeing temporaries and lexicals from.
3727 =item panic: pad_sv po
3729 (P) An invalid scratch pad offset was detected internally.
3731 =item panic: pad_swipe curpad, %p!=%p
3733 (P) The compiler got confused about which scratch pad it was allocating
3734 and freeing temporaries and lexicals from.
3736 =item panic: pad_swipe po
3738 (P) An invalid scratch pad offset was detected internally.
3740 =item panic: pp_iter, type=%u
3742 (P) The foreach iterator got called in a non-loop context frame.
3744 =item panic: pp_match%s
3746 (P) The internal pp_match() routine was called with invalid operational
3749 =item panic: pp_split, pm=%p, s=%p
3751 (P) Something terrible went wrong in setting up for the split.
3753 =item panic: realloc, %s
3755 (P) Something requested a negative number of bytes of realloc.
3757 =item panic: reference miscount on nsv in sv_replace() (%d != 1)
3759 (P) The internal sv_replace() function was handed a new SV with a
3760 reference count other than 1.
3762 =item panic: restartop in %s
3764 (P) Some internal routine requested a goto (or something like it), and
3765 didn't supply the destination.
3767 =item panic: return, type=%u
3769 (P) We popped the context stack to a subroutine or eval context, and
3770 then discovered it wasn't a subroutine or eval context.
3772 =item panic: scan_num, %s
3774 (P) scan_num() got called on something that wasn't a number.
3776 =item panic: Sequence (?{...}): no code block found
3778 (P) while compiling a pattern that has embedded (?{}) or (??{}) code
3779 blocks, perl couldn't locate the code block that should have already been
3780 seen and compiled by perl before control passed to the regex compiler.
3782 =item panic: sv_chop %s
3784 (P) The sv_chop() routine was passed a position that is not within the
3785 scalar's string buffer.
3787 =item panic: sv_insert, midend=%p, bigend=%p
3789 (P) The sv_insert() routine was told to remove more string than there
3792 =item panic: strxfrm() gets absurd - a => %u, ab => %u
3794 (P) The interpreter's sanity check of the C function strxfrm() failed.
3795 In your current locale the returned transformation of the string "ab" is
3796 shorter than that of the string "a", which makes no sense.
3798 =item panic: top_env
3800 (P) The compiler attempted to do a goto, or something weird like that.
3802 =item panic: unimplemented op %s (#%d) called
3804 (P) The compiler is screwed up and attempted to use an op that isn't
3805 permitted at run time.
3807 =item panic: utf16_to_utf8: odd bytelen
3809 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
3810 to even) byte length.
3812 =item panic: utf16_to_utf8_reversed: odd bytelen
3814 (P) Something tried to call utf16_to_utf8_reversed with an odd (as opposed
3815 to even) byte length.
3817 =item panic: yylex, %s
3819 (P) The lexer got into a bad state while processing a case modifier.
3821 =item Parentheses missing around "%s" list
3823 (W parenthesis) You said something like
3829 my ($foo, $bar) = @_;
3831 Remember that "my", "our", "local" and "state" bind tighter than comma.
3833 =item Parsing code internal error (%s)
3835 (F) Parsing code supplied by an extension violated the parser's API in
3838 =item Passing malformed UTF-8 to "%s" is deprecated
3840 (D deprecated, utf8) This message indicates a bug either in the Perl
3841 core or in XS code. Such code was trying to find out if a character,
3842 allegedly stored internally encoded as UTF-8, was of a given type, such
3843 as being punctuation or a digit. But the character was not encoded in
3844 legal UTF-8. The C<%s> is replaced by a string that can be used by
3845 knowledgeable people to determine what the type being checked against
3846 was. If C<utf8> warnings are enabled, a further message is raised,
3847 giving details of the malformation.
3849 =item Pattern subroutine nesting without pos change exceeded limit in regex;
3850 marked by <-- HERE in m/%s/
3852 (F) You used a pattern that uses too many nested subpattern calls without
3853 consuming any text. Restructure the pattern so text is consumed before
3854 the nesting limit is exceeded.
3856 The <-- HERE shows whereabouts in the regular expression the problem was
3859 =item C<-p> destination: %s
3861 (F) An error occurred during the implicit output invoked by the C<-p>
3862 command-line switch. (This output goes to STDOUT unless you've
3863 redirected it with select().)
3865 =item (perhaps you forgot to load "%s"?)
3867 (F) This is an educated guess made in conjunction with the message
3868 "Can't locate object method \"%s\" via package \"%s\"". It often means
3869 that a method requires a package that has not been loaded.
3871 =item Perl folding rules are not up-to-date for 0x%X; please use the perlbug
3872 utility to report; in regex; marked by <-- HERE in m/%s/
3874 (D regexp, deprecated) You used a regular expression with
3875 case-insensitive matching, and there is a bug in Perl in which the
3876 built-in regular expression folding rules are not accurate. This may
3877 lead to incorrect results. Please report this as a bug using the
3878 "perlbug" utility. (This message is marked deprecated, so that it by
3879 default will be turned-on.)
3881 =item Perl_my_%s() not available
3883 (F) Your platform has very uncommon byte-order and integer size,
3884 so it was not possible to set up some or all fixed-width byte-order
3885 conversion functions. This is only a problem when you're using the
3886 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
3888 =item Perl %s required (did you mean %s?)--this is only %s, stopped
3890 (F) The code you are trying to run has asked for a newer version of
3891 Perl than you are running. Perhaps C<use 5.10> was written instead
3892 of C<use 5.010> or C<use v5.10>. Without the leading C<v>, the number is
3893 interpreted as a decimal, with every three digits after the
3894 decimal point representing a part of the version number. So 5.10
3895 is equivalent to v5.100.
3897 =item Perl %s required--this is only version %s, stopped
3899 (F) The module in question uses features of a version of Perl more
3900 recent than the currently running version. How long has it been since
3901 you upgraded, anyway? See L<perlfunc/require>.
3903 =item PERL_SH_DIR too long
3905 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
3906 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
3908 =item PERL_SIGNALS illegal: "%s"
3910 (X) See L<perlrun/PERL_SIGNALS> for legal values.
3912 =item Perls since %s too modern--this is %s, stopped
3914 (F) The code you are trying to run claims it will not run
3915 on the version of Perl you are using because it is too new.
3916 Maybe the code needs to be updated, or maybe it is simply
3917 wrong and the version check should just be removed.
3919 =item perl: warning: Setting locale failed.
3921 (S) The whole warning message will look something like:
3923 perl: warning: Setting locale failed.
3924 perl: warning: Please check that your locale settings:
3927 are supported and installed on your system.
3928 perl: warning: Falling back to the standard locale ("C").
3930 Exactly what were the failed locale settings varies. In the above the
3931 settings were that the LC_ALL was "En_US" and the LANG had no value.
3932 This error means that Perl detected that you and/or your operating
3933 system supplier and/or system administrator have set up the so-called
3934 locale system but Perl could not use those settings. This was not
3935 dead serious, fortunately: there is a "default locale" called "C" that
3936 Perl can and will use, and the script will be run. Before you really
3937 fix the problem, however, you will get the same error message each
3938 time you run Perl. How to really fix the problem can be found in
3939 L<perllocale> section B<LOCALE PROBLEMS>.
3941 =item perl: warning: Non hex character in '$ENV{PERL_HASH_SEED}', seed only
3944 (W) PERL_HASH_SEED should match /^\s*(?:0x)?[0-9a-fA-F]+\s*\z/ but it
3945 contained a non hex character. This could mean your hash randomization
3946 is not being set correctly.
3948 =item pid %x not a child
3950 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
3951 process which isn't a subprocess of the current process. While this is
3952 fine from VMS' perspective, it's probably not what you intended.
3954 =item 'P' must have an explicit size in unpack
3956 (F) The unpack format P must have an explicit size, not "*".
3958 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
3960 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
3961 shows whereabouts in the regular expression the problem was discovered.
3962 Note that the POSIX character classes do B<not> have the C<is> prefix
3963 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
3964 not C<isprint>. See L<perlre>.
3966 =item POSIX getpgrp can't take an argument
3968 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
3969 the BSD version, which takes a pid.
3971 =item POSIX syntax [%c %c] belongs inside character classes in regex; marked by
3974 (W regexp) The character class constructs [: :], [= =], and [. .] go
3975 I<inside> character classes, the [] are part of the construct, for example:
3976 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
3977 implemented; they are simply placeholders for future extensions and
3978 will cause fatal errors. The <-- HERE shows whereabouts in the regular
3979 expression the problem was discovered. See L<perlre>.
3981 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by
3984 (F) Within regular expression character classes ([]) the syntax beginning
3985 with "[." and ending with ".]" is reserved for future extensions. If you
3986 need to represent those character sequences inside a regular expression
3987 character class, just quote the square brackets with the backslash: "\[."
3988 and ".\]". The <-- HERE shows whereabouts in the regular expression the
3989 problem was discovered. See L<perlre>.
3991 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by
3994 (F) Within regular expression character classes ([]) the syntax beginning
3995 with "[=" and ending with "=]" is reserved for future extensions. If you
3996 need to represent those character sequences inside a regular expression
3997 character class, just quote the square brackets with the backslash: "\[="
3998 and "=\]". The <-- HERE shows whereabouts in the regular expression the
3999 problem was discovered. See L<perlre>.
4001 =item Possible attempt to put comments in qw() list
4003 (W qw) qw() lists contain items separated by whitespace; as with literal
4004 strings, comment characters are not ignored, but are instead treated as
4005 literal data. (You may have used different delimiters than the
4006 parentheses shown here; braces are also frequently used.)
4008 You probably wrote something like this:
4015 when you should have written this:
4022 If you really want comments, build your list the
4023 old-fashioned way, with quotes and commas:
4027 'b', # another comment
4030 =item Possible attempt to separate words with commas
4032 (W qw) qw() lists contain items separated by whitespace; therefore
4033 commas aren't needed to separate the items. (You may have used
4034 different delimiters than the parentheses shown here; braces are also
4037 You probably wrote something like this:
4041 which puts literal commas into some of the list items. Write it without
4042 commas if you don't want them to appear in your data:
4046 =item Possible memory corruption: %s overflowed 3rd argument
4048 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
4049 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
4050 end of the buffer just in case. This sentinel byte got clobbered, and
4051 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
4053 =item Possible precedence problem on bitwise %c operator
4055 (W precedence) Your program uses a bitwise logical operator in conjunction
4056 with a numeric comparison operator, like this :
4058 if ($x & $y == 0) { ... }
4060 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
4061 higher precedence of C<==>. This is probably not what you want. (If you
4062 really meant to write this, disable the warning, or, better, put the
4063 parentheses explicitly and write C<$x & ($y == 0)>).
4065 =item Possible unintended interpolation of $\ in regex
4067 (W ambiguous) You said something like C<m/$\/> in a regex.
4068 The regex C<m/foo$\s+bar/m> translates to: match the word 'foo', the output
4069 record separator (see L<perlvar/$\>) and the letter 's' (one time or more)
4070 followed by the word 'bar'.
4072 If this is what you intended then you can silence the warning by using
4073 C<m/${\}/> (for example: C<m/foo${\}s+bar/>).
4075 If instead you intended to match the word 'foo' at the end of the line
4076 followed by whitespace and the word 'bar' on the next line then you can use
4077 C<m/$(?)\/> (for example: C<m/foo$(?)\s+bar/>).
4079 =item Possible unintended interpolation of %s in string
4081 (W ambiguous) You said something like '@foo' in a double-quoted string
4082 but there was no array C<@foo> in scope at the time. If you wanted a
4083 literal @foo, then write it as \@foo; otherwise find out what happened
4084 to the array you apparently lost track of.
4086 =item Precedence problem: open %s should be open(%s)
4088 (S precedence) The old irregular construct
4092 is now misinterpreted as
4096 because of the strict regularization of Perl 5's grammar into unary and
4097 list operators. (The old open was a little of both.) You must put
4098 parentheses around the filehandle, or use the new "or" operator instead
4101 =item Premature end of script headers
4105 =item printf() on closed filehandle %s
4107 (W closed) The filehandle you're writing to got itself closed sometime
4108 before now. Check your control flow.
4110 =item print() on closed filehandle %s
4112 (W closed) The filehandle you're printing on got itself closed sometime
4113 before now. Check your control flow.
4115 =item Process terminated by SIG%s
4117 (W) This is a standard message issued by OS/2 applications, while *nix
4118 applications die in silence. It is considered a feature of the OS/2
4119 port. One can easily disable this by appropriate sighandlers, see
4120 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
4123 =item Prototype after '%c' for %s : %s
4125 (W illegalproto) A character follows % or @ in a prototype. This is
4126 useless, since % and @ gobble the rest of the subroutine arguments.
4128 =item Prototype mismatch: %s vs %s
4130 (S prototype) The subroutine being declared or defined had previously been
4131 declared or defined with a different function prototype.
4133 =item Prototype not terminated
4135 (F) You've omitted the closing parenthesis in a function prototype
4138 =item \p{} uses Unicode rules, not locale rules
4140 (W) You compiled a regular expression that contained a Unicode property
4141 match (C<\p> or C<\P>), but the regular expression is also being told to
4142 use the run-time locale, not Unicode. Instead, use a POSIX character
4143 class, which should know about the locale's rules.
4144 (See L<perlrecharclass/POSIX Character Classes>.)
4146 Even if the run-time locale is ISO 8859-1 (Latin1), which is a subset of
4147 Unicode, some properties will give results that are not valid for that
4150 Here are a couple of examples to help you see what's going on. If the
4151 locale is ISO 8859-7, the character at code point 0xD7 is the "GREEK
4152 CAPITAL LETTER CHI". But in Unicode that code point means the
4153 "MULTIPLICATION SIGN" instead, and C<\p> always uses the Unicode
4154 meaning. That means that C<\p{Alpha}> won't match, but C<[[:alpha:]]>
4155 should. Only in the Latin1 locale are all the characters in the same
4156 positions as they are in Unicode. But, even here, some properties give
4157 incorrect results. An example is C<\p{Changes_When_Uppercased}> which
4158 is true for "LATIN SMALL LETTER Y WITH DIAERESIS", but since the upper
4159 case of that character is not in Latin1, in that locale it doesn't
4160 change when upper cased.
4162 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
4164 (F) You started a regular expression with a quantifier. Backslash it if
4165 you meant it literally. The <-- HERE shows whereabouts in the regular
4166 expression the problem was discovered. See L<perlre>.
4168 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
4170 (F) There is currently a limit to the size of the min and max values of
4171 the {min,max} construct. The <-- HERE shows whereabouts in the regular
4172 expression the problem was discovered. See L<perlre>.
4174 =item Quantifier unexpected on zero-length expression in regex; marked by <--
4177 (W regexp) You applied a regular expression quantifier in a place where
4178 it makes no sense, such as on a zero-width assertion. Try putting the
4179 quantifier inside the assertion instead. For example, the way to match
4180 "abc" provided that it is followed by three repetitions of "xyz" is
4181 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
4183 The <-- HERE shows whereabouts in the regular expression the problem was
4186 =item Quantifier {n,m} with n > m can't match in regex; marked by <-- HERE in m/%s/
4188 (W regexp) Minima should be less than or equal to maxima. If you really
4189 want your regexp to match something 0 times, just put {0}.
4191 =item Range iterator outside integer range
4193 (F) One (or both) of the numeric arguments to the range operator ".."
4194 are outside the range which can be represented by integers internally.
4195 One possible workaround is to force Perl to use magical string increment
4196 by prepending "0" to your numbers.
4198 =item readdir() attempted on invalid dirhandle %s
4200 (W io) The dirhandle you're reading from is either closed or not really
4201 a dirhandle. Check your control flow.
4203 =item readline() on closed filehandle %s
4205 (W closed) The filehandle you're reading from got itself closed sometime
4206 before now. Check your control flow.
4208 =item read() on closed filehandle %s
4210 (W closed) You tried to read from a closed filehandle.
4212 =item read() on unopened filehandle %s
4214 (W unopened) You tried to read from a filehandle that was never opened.
4216 =item Reallocation too large: %x
4218 (F) You can't allocate more than 64K on an MS-DOS machine.
4220 =item realloc() of freed memory ignored
4222 (S malloc) An internal routine called realloc() on something that had
4225 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
4227 (S debugging) You can't use the B<-D> option unless the code to produce
4228 the desired output is compiled into Perl, which entails some overhead,
4229 which is why it's currently left out of your copy.
4231 =item Recursive call to Perl_load_module in PerlIO_find_layer
4233 (P) It is currently not permitted to load modules when creating
4234 a filehandle inside an %INC hook. This can happen with C<open my
4235 $fh, '<', \$scalar>, which implicitly loads PerlIO::scalar. Try
4236 loading PerlIO::scalar explicitly first.
4238 =item Recursive inheritance detected in package '%s'
4240 (F) While calculating the method resolution order (MRO) of a package, Perl
4241 believes it found an infinite loop in the C<@ISA> hierarchy. This is a
4242 crude check that bails out after 100 levels of C<@ISA> depth.
4244 =item refcnt_dec: fd %d%s
4246 =item refcnt: fd %d%s
4248 =item refcnt_inc: fd %d%s
4250 (P) Perl's I/O implementation failed an internal consistency check. If
4251 you see this message, something is very wrong.
4253 =item Reference found where even-sized list expected
4255 (W misc) You gave a single reference where Perl was expecting a list
4256 with an even number of elements (for assignment to a hash). This
4257 usually means that you used the anon hash constructor when you meant
4258 to use parens. In any case, a hash requires key/value B<pairs>.
4260 %hash = { one => 1, two => 2, }; # WRONG
4261 %hash = [ qw/ an anon array / ]; # WRONG
4262 %hash = ( one => 1, two => 2, ); # right
4263 %hash = qw( one 1 two 2 ); # also fine
4265 =item Reference is already weak
4267 (W misc) You have attempted to weaken a reference that is already weak.
4268 Doing so has no effect.
4270 =item Reference to invalid group 0 in regex; marked by <-- HERE in m/%s/
4272 (F) You used C<\g0> or similar in a regular expression. You may refer
4273 to capturing parentheses only with strictly positive integers
4274 (normal backreferences) or with strictly negative integers (relative
4275 backreferences). Using 0 does not make sense.
4277 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
4279 (F) You used something like C<\7> in your regular expression, but there are
4280 not at least seven sets of capturing parentheses in the expression. If
4281 you wanted to have the character with ordinal 7 inserted into the regular
4282 expression, prepend zeroes to make it three digits long: C<\007>
4284 The <-- HERE shows whereabouts in the regular expression the problem was
4287 =item Reference to nonexistent named group in regex; marked by <-- HERE in m/%s/
4289 (F) You used something like C<\k'NAME'> or C<< \k<NAME> >> in your regular
4290 expression, but there is no corresponding named capturing parentheses
4291 such as C<(?'NAME'...)> or C<< (?<NAME>...) >>. Check if the name has been
4292 spelled correctly both in the backreference and the declaration.
4294 The <-- HERE shows whereabouts in the regular expression the problem was
4297 =item Reference to nonexistent or unclosed group in regex; marked by <-- HERE
4300 (F) You used something like C<\g{-7}> in your regular expression, but there
4301 are not at least seven sets of closed capturing parentheses in the
4302 expression before where the C<\g{-7}> was located.
4304 The <-- HERE shows whereabouts in the regular expression the problem was
4307 =item regexp memory corruption
4309 (P) The regular expression engine got confused by what the regular
4310 expression compiler gave it.
4312 =item Regexp modifier "/%c" may appear a maximum of twice
4314 =item Regexp modifier "/%c" may not appear twice
4316 (F syntax, regexp) The regular expression pattern had too many occurrences
4317 of the specified modifier. Remove the extraneous ones.
4319 =item Regexp modifier "%c" may not appear after the "-" in regex; marked by <--
4322 (F) Turning off the given modifier has the side effect of turning on
4323 another one. Perl currently doesn't allow this. Reword the regular
4324 expression to use the modifier you want to turn on (and place it before
4325 the minus), instead of the one you want to turn off.
4327 =item Regexp modifiers "/%c" and "/%c" are mutually exclusive
4329 (F syntax, regexp) The regular expression pattern had more than one of these
4330 mutually exclusive modifiers. Retain only the modifier that is
4331 supposed to be there.
4333 =item Regexp out of space in regex m/%s/
4335 (P) A "can't happen" error, because safemalloc() should have caught it
4338 =item Repeated format line will never terminate (~~ and @# incompatible)
4340 (F) Your format contains the ~~ repeat-until-blank sequence and a
4341 numeric field that will never go blank so that the repetition never
4342 terminates. You might use ^# instead. See L<perlform>.
4344 =item Replacement list is longer than search list
4346 (W misc) You have used a replacement list that is longer than the
4347 search list. So the additional elements in the replacement list
4350 =item '%s' resolved to '\o{%s}%d'
4352 (W misc, regexp) You wrote something like C<\08>, or C<\179> in a
4353 double-quotish string. All but the last digit is treated as a single
4354 character, specified in octal. The last digit is the next character in
4355 the string. To tell Perl that this is indeed what you want, you can use
4356 the C<\o{ }> syntax, or use exactly three digits to specify the octal
4359 =item Reversed %s= operator
4361 (W syntax) You wrote your assignment operator backwards. The = must
4362 always come last, to avoid ambiguity with subsequent unary operators.
4364 =item rewinddir() attempted on invalid dirhandle %s
4366 (W io) The dirhandle you tried to do a rewinddir() on is either closed or not
4367 really a dirhandle. Check your control flow.
4369 =item Scalars leaked: %d
4371 (S internal) Something went wrong in Perl's internal bookkeeping
4372 of scalars: not all scalar variables were deallocated by the time
4373 Perl exited. What this usually indicates is a memory leak, which
4374 is of course bad, especially if the Perl program is intended to be
4377 =item Scalar value @%s[%s] better written as $%s[%s]
4379 (W syntax) You've used an array slice (indicated by @) to select a
4380 single element of an array. Generally it's better to ask for a scalar
4381 value (indicated by $). The difference is that C<$foo[&bar]> always
4382 behaves like a scalar, both when assigning to it and when evaluating its
4383 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
4384 and provides a list context to its subscript, which can do weird things
4385 if you're expecting only one subscript.
4387 On the other hand, if you were actually hoping to treat the array
4388 element as a list, you need to look into how references work, because
4389 Perl will not magically convert between scalars and lists for you. See
4392 =item Scalar value @%s{%s} better written as $%s{%s}
4394 (W syntax) You've used a hash slice (indicated by @) to select a single
4395 element of a hash. Generally it's better to ask for a scalar value
4396 (indicated by $). The difference is that C<$foo{&bar}> always behaves
4397 like a scalar, both when assigning to it and when evaluating its
4398 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
4399 and provides a list context to its subscript, which can do weird things
4400 if you're expecting only one subscript.
4402 On the other hand, if you were actually hoping to treat the hash element
4403 as a list, you need to look into how references work, because Perl will
4404 not magically convert between scalars and lists for you. See
4407 =item Search pattern not terminated
4409 (F) The lexer couldn't find the final delimiter of a // or m{}
4410 construct. Remember that bracketing delimiters count nesting level.
4411 Missing the leading C<$> from a variable C<$m> may cause this error.
4413 Note that since Perl 5.9.0 a // can also be the I<defined-or>
4414 construct, not just the empty search pattern. Therefore code written
4415 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
4416 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
4418 =item Search pattern not terminated or ternary operator parsed as search pattern
4420 (F) The lexer couldn't find the final delimiter of a C<?PATTERN?>
4423 The question mark is also used as part of the ternary operator (as in
4424 C<foo ? 0 : 1>) leading to some ambiguous constructions being wrongly
4425 parsed. One way to disambiguate the parsing is to put parentheses around
4426 the conditional expression, i.e. C<(foo) ? 0 : 1>.
4428 =item seekdir() attempted on invalid dirhandle %s
4430 (W io) The dirhandle you are doing a seekdir() on is either closed or not
4431 really a dirhandle. Check your control flow.
4433 =item %sseek() on unopened filehandle
4435 (W unopened) You tried to use the seek() or sysseek() function on a
4436 filehandle that was either never opened or has since been closed.
4438 =item select not implemented
4440 (F) This machine doesn't implement the select() system call.
4442 =item Self-ties of arrays and hashes are not supported
4444 (F) Self-ties are of arrays and hashes are not supported in
4445 the current implementation.
4447 =item Semicolon seems to be missing
4449 (W semicolon) A nearby syntax error was probably caused by a missing
4450 semicolon, or possibly some other missing operator, such as a comma.
4452 =item semi-panic: attempt to dup freed string
4454 (S internal) The internal newSVsv() routine was called to duplicate a
4455 scalar that had previously been marked as free.
4457 =item sem%s not implemented
4459 (F) You don't have System V semaphore IPC on your system.
4461 =item send() on closed socket %s
4463 (W closed) The socket you're sending to got itself closed sometime
4464 before now. Check your control flow.
4466 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
4468 (F) A regular expression ended with an incomplete extension (?. The
4469 <-- HERE shows whereabouts in the regular expression the problem was
4470 discovered. See L<perlre>.
4472 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
4474 (F) A proposed regular expression extension has the character reserved
4475 but has not yet been written. The <-- HERE shows whereabouts in the
4476 regular expression the problem was discovered. See L<perlre>.
4478 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
4480 (F) You used a regular expression extension that doesn't make sense. The
4481 <-- HERE shows whereabouts in the regular expression the problem was
4482 discovered. This happens when using the C<(?^...)> construct to tell
4483 Perl to use the default regular expression modifiers, and you
4484 redundantly specify a default modifier. For other
4485 causes, see L<perlre>.
4487 =item Sequence \%s... not terminated in regex; marked by <-- HERE in m/%s/
4489 (F) The regular expression expects a mandatory argument following the escape
4490 sequence and this has been omitted or incorrectly written.
4492 =item Sequence (?#... not terminated in regex m/%s/
4494 (F) A regular expression comment must be terminated by a closing
4495 parenthesis. Embedded parentheses aren't allowed. See
4498 =item Sequence (?{...}) not terminated with ')'
4500 (F) The end of the perl code contained within the {...} must be
4501 followed immediately by a ')'.
4503 =item Z<>500 Server error
4509 (A) This is the error message generally seen in a browser window
4510 when trying to run a CGI program (including SSI) over the web. The
4511 actual error text varies widely from server to server. The most
4512 frequently-seen variants are "500 Server error", "Method (something)
4513 not permitted", "Document contains no data", "Premature end of script
4514 headers", and "Did not produce a valid header".
4516 B<This is a CGI error, not a Perl error>.
4518 You need to make sure your script is executable, is accessible by
4519 the user CGI is running the script under (which is probably not the
4520 user account you tested it under), does not rely on any environment
4521 variables (like PATH) from the user it isn't running under, and isn't
4522 in a location where the CGI server can't find it, basically, more or
4523 less. Please see the following for more information:
4525 http://www.perl.org/CGI_MetaFAQ.html
4526 http://www.htmlhelp.org/faq/cgifaq.html
4527 http://www.w3.org/Security/Faq/
4529 You should also look at L<perlfaq9>.
4531 =item setegid() not implemented
4533 (F) You tried to assign to C<$)>, and your operating system doesn't
4534 support the setegid() system call (or equivalent), or at least Configure
4537 =item seteuid() not implemented
4539 (F) You tried to assign to C<< $> >>, and your operating system doesn't
4540 support the seteuid() system call (or equivalent), or at least Configure
4543 =item setpgrp can't take arguments
4545 (F) Your system has the setpgrp() from BSD 4.2, which takes no
4546 arguments, unlike POSIX setpgid(), which takes a process ID and process
4549 =item setrgid() not implemented
4551 (F) You tried to assign to C<$(>, and your operating system doesn't
4552 support the setrgid() system call (or equivalent), or at least Configure
4555 =item setruid() not implemented
4557 (F) You tried to assign to C<$<>, and your operating system doesn't
4558 support the setruid() system call (or equivalent), or at least Configure
4561 =item setsockopt() on closed socket %s
4563 (W closed) You tried to set a socket option on a closed socket. Did you
4564 forget to check the return value of your socket() call? See
4565 L<perlfunc/setsockopt>.
4567 =item shm%s not implemented
4569 (F) You don't have System V shared memory IPC on your system.
4571 =item !=~ should be !~
4573 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
4574 interpreted as the != (numeric not equal) and ~ (1's complement)
4575 operators: probably not what you intended.
4577 =item <> should be quotes
4579 (F) You wrote C<< require <file> >> when you should have written
4582 =item /%s/ should probably be written as "%s"
4584 (W syntax) You have used a pattern where Perl expected to find a string,
4585 as in the first argument to C<join>. Perl will treat the true or false
4586 result of matching the pattern against $_ as the string, which is
4587 probably not what you had in mind.
4589 =item shutdown() on closed socket %s
4591 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
4594 =item SIG%s handler "%s" not defined
4596 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
4597 Perhaps you put it into the wrong package?
4599 =item Slab leaked from cv %p
4601 (S) If you see this message, then something is seriously wrong with the
4602 internal bookkeeping of op trees. An op tree needed to be freed after
4603 a compilation error, but could not be found, so it was leaked instead.
4605 =item sleep(%u) too large
4607 (W overflow) You called C<sleep> with a number that was larger than
4608 it can reliably handle and C<sleep> probably slept for less time than
4611 =item Smart matching a non-overloaded object breaks encapsulation
4613 (F) You should not use the C<~~> operator on an object that does not
4614 overload it: Perl refuses to use the object's underlying structure for
4617 =item sort is now a reserved word
4619 (F) An ancient error message that almost nobody ever runs into anymore.
4620 But before sort was a keyword, people sometimes used it as a filehandle.
4622 =item Sort subroutine didn't return single value
4624 (F) A sort comparison subroutine written in XS must return exactly one
4625 item. See L<perlfunc/sort>.
4627 =item Source filters apply only to byte streams
4629 (F) You tried to activate a source filter (usually by loading a
4630 source filter module) within a string passed to C<eval>. This is
4631 not permitted under the C<unicode_eval> feature. Consider using
4632 C<evalbytes> instead. See L<feature>.
4634 =item splice() offset past end of array
4636 (W misc) You attempted to specify an offset that was past the end of
4637 the array passed to splice(). Splicing will instead commence at the
4638 end of the array, rather than past it. If this isn't what you want,
4639 try explicitly pre-extending the array by assigning $#array = $offset.
4640 See L<perlfunc/splice>.
4644 (P) The split was looping infinitely. (Obviously, a split shouldn't
4645 iterate more times than there are characters of input, which is what
4646 happened.) See L<perlfunc/split>.
4648 =item Statement unlikely to be reached
4650 (W exec) You did an exec() with some statement after it other than a
4651 die(). This is almost always an error, because exec() never returns
4652 unless there was a failure. You probably wanted to use system()
4653 instead, which does return. To suppress this warning, put the exec() in
4656 =item "state" variable %s can't be in a package
4658 (F) Lexically scoped variables aren't in a package, so it doesn't make
4659 sense to try to declare one with a package qualifier on the front. Use
4660 local() if you want to localize a package variable.
4662 =item "state %s" used in sort comparison
4664 (W syntax) The package variables $a and $b are used for sort comparisons.
4665 You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
4666 sort comparison block, and the variable had earlier been declared as a
4667 lexical variable. Either qualify the sort variable with the package
4668 name, or rename the lexical variable.
4670 =item stat() on unopened filehandle %s
4672 (W unopened) You tried to use the stat() function on a filehandle that
4673 was either never opened or has since been closed.
4675 =item Stub found while resolving method "%s" overloading "%s" in package "%s"
4677 (P) Overloading resolution over @ISA tree may be broken by importation
4678 stubs. Stubs should never be implicitly created, but explicit calls to
4679 C<can> may break this.
4681 =item Subroutine "&%s" is not available
4683 (W closure) During compilation, an inner named subroutine or eval is
4684 attempting to capture an outer lexical subroutine that is not currently
4685 available. This can happen for one of two reasons. First, the lexical
4686 subroutine may be declared in an outer anonymous subroutine that has not
4687 yet been created. (Remember that named subs are created at compile time,
4688 while anonymous subs are created at run-time.) For example,
4690 sub { my sub a {...} sub f { \&a } }
4692 At the time that f is created, it can't capture the current the "a" sub,
4693 since the anonymous subroutine hasn't been created yet. Conversely, the
4694 following won't give a warning since the anonymous subroutine has by now
4695 been created and is live:
4697 sub { my sub a {...} eval 'sub f { \&a }' }->();
4699 The second situation is caused by an eval accessing a variable that has
4700 gone out of scope, for example,
4708 Here, when the '\&a' in the eval is being compiled, f() is not currently
4709 being executed, so its &a is not available for capture.
4711 =item "%s" subroutine &%s masks earlier declaration in same %s
4713 (W misc) A "my" or "state" subroutine has been redeclared in the
4714 current scope or statement, effectively eliminating all access to
4715 the previous instance. This is almost always a typographical error.
4716 Note that the earlier subroutine will still exist until the end of
4717 the scope or until all closure references to it are destroyed.
4719 =item Subroutine %s redefined
4721 (W redefine) You redefined a subroutine. To suppress this warning, say
4724 no warnings 'redefine';
4725 eval "sub name { ... }";
4728 =item Substitution loop
4730 (P) The substitution was looping infinitely. (Obviously, a substitution
4731 shouldn't iterate more times than there are characters of input, which
4732 is what happened.) See the discussion of substitution in
4733 L<perlop/"Regexp Quote-Like Operators">.
4735 =item Substitution pattern not terminated
4737 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
4738 construct. Remember that bracketing delimiters count nesting level.
4739 Missing the leading C<$> from variable C<$s> may cause this error.
4741 =item Substitution replacement not terminated
4743 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
4744 construct. Remember that bracketing delimiters count nesting level.
4745 Missing the leading C<$> from variable C<$s> may cause this error.
4747 =item substr outside of string
4749 (W substr)(F) You tried to reference a substr() that pointed outside of
4750 a string. That is, the absolute value of the offset was larger than the
4751 length of the string. See L<perlfunc/substr>. This warning is fatal if
4752 substr is used in an lvalue context (as the left hand side of an
4753 assignment or as a subroutine argument for example).
4755 =item sv_upgrade from type %d down to type %d
4757 (P) Perl tried to force the upgrade of an SV to a type which was actually
4758 inferior to its current type.
4760 =item Switch (?(condition)... contains too many branches in regex; marked by
4763 (F) A (?(condition)if-clause|else-clause) construct can have at most
4764 two branches (the if-clause and the else-clause). If you want one or
4765 both to contain alternation, such as using C<this|that|other>, enclose
4766 it in clustering parentheses:
4768 (?(condition)(?:this|that|other)|else-clause)
4770 The <-- HERE shows whereabouts in the regular expression the problem
4771 was discovered. See L<perlre>.
4773 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
4775 (F) If the argument to the (?(...)if-clause|else-clause) construct is
4776 a number, it can be only a number. The <-- HERE shows whereabouts in
4777 the regular expression the problem was discovered. See L<perlre>.
4779 =item switching effective %s is not implemented
4781 (F) While under the C<use filetest> pragma, we cannot switch the real
4782 and effective uids or gids.
4786 (F) The final summary message when a C<perl -c> succeeds.
4790 (F) Probably means you had a syntax error. Common reasons include:
4792 A keyword is misspelled.
4793 A semicolon is missing.
4795 An opening or closing parenthesis is missing.
4796 An opening or closing brace is missing.
4797 A closing quote is missing.
4799 Often there will be another error message associated with the syntax
4800 error giving more information. (Sometimes it helps to turn on B<-w>.)
4801 The error message itself often tells you where it was in the line when
4802 it decided to give up. Sometimes the actual error is several tokens
4803 before this, because Perl is good at understanding random input.
4804 Occasionally the line number may be misleading, and once in a blue moon
4805 the only way to figure out what's triggering the error is to call
4806 C<perl -c> repeatedly, chopping away half the program each time to see
4807 if the error went away. Sort of the cybernetic version of S<20 questions>.
4809 =item syntax error at line %d: '%s' unexpected
4811 (A) You've accidentally run your script through the Bourne shell instead
4812 of Perl. Check the #! line, or manually feed your script into Perl
4815 =item syntax error in file %s at line %d, next 2 tokens "%s"
4817 (F) This error is likely to occur if you run a perl5 script through
4818 a perl4 interpreter, especially if the next 2 tokens are "use strict"
4819 or "my $var" or "our $var".
4821 =item sysread() on closed filehandle %s
4823 (W closed) You tried to read from a closed filehandle.
4825 =item sysread() on unopened filehandle %s
4827 (W unopened) You tried to read from a filehandle that was never opened.
4829 =item System V %s is not implemented on this machine
4831 (F) You tried to do something with a function beginning with "sem",
4832 "shm", or "msg" but that System V IPC is not implemented in your
4833 machine. In some machines the functionality can exist but be
4834 unconfigured. Consult your system support.
4836 =item syswrite() on closed filehandle %s
4838 (W closed) The filehandle you're writing to got itself closed sometime
4839 before now. Check your control flow.
4841 =item C<-T> and C<-B> not implemented on filehandles
4843 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
4844 know about your kind of stdio. You'll have to use a filename instead.
4846 =item Target of goto is too deeply nested
4848 (F) You tried to use C<goto> to reach a label that was too deeply nested
4849 for Perl to reach. Perl is doing you a favor by refusing.
4851 =item telldir() attempted on invalid dirhandle %s
4853 (W io) The dirhandle you tried to telldir() is either closed or not really
4854 a dirhandle. Check your control flow.
4856 =item tell() on unopened filehandle
4858 (W unopened) You tried to use the tell() function on a filehandle that
4859 was either never opened or has since been closed.
4861 =item That use of $[ is unsupported
4863 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
4864 as a compiler directive. You may say only one of
4873 This is to prevent the problem of one module changing the array base out
4874 from under another module inadvertently. See L<perlvar/$[> and L<arybase>.
4876 =item The crypt() function is unimplemented due to excessive paranoia.
4878 (F) Configure couldn't find the crypt() function on your machine,
4879 probably because your vendor didn't supply it, probably because they
4880 think the U.S. Government thinks it's a secret, or at least that they
4881 will continue to pretend that it is. And if you quote me on that, I
4884 =item The lexical_subs feature is experimental
4886 (S experimental::lexical_subs) This warning is emitted if you
4887 declare a sub with C<my> or C<state>. Simply suppress the warning
4888 if you want to use the feature, but know that in doing so you
4889 are taking the risk of using an experimental feature which may
4890 change or be removed in a future Perl version:
4892 no warnings "experimental::lexical_subs";
4893 use feature "lexical_subs";
4896 =item The %s function is unimplemented
4898 (F) The function indicated isn't implemented on this architecture, according
4899 to the probings of Configure.
4901 =item The stat preceding %s wasn't an lstat
4903 (F) It makes no sense to test the current stat buffer for symbolic
4904 linkhood if the last stat that wrote to the stat buffer already went
4905 past the symlink to get to the real file. Use an actual filename
4908 =item The 'unique' attribute may only be applied to 'our' variables
4910 (F) This attribute was never supported on C<my> or C<sub> declarations.
4912 =item This Perl can't reset CRTL environ elements (%s)
4914 =item This Perl can't set CRTL environ elements (%s=%s)
4916 (W internal) Warnings peculiar to VMS. You tried to change or delete an
4917 element of the CRTL's internal environ array, but your copy of Perl
4918 wasn't built with a CRTL that contained the setenv() function. You'll
4919 need to rebuild Perl with a CRTL that does, or redefine
4920 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
4921 target of the change to
4922 %ENV which produced the warning.
4924 =item thread failed to start: %s
4926 (W threads)(S) The entry point function of threads->create() failed for some reason.
4928 =item times not implemented
4930 (F) Your version of the C library apparently doesn't do times(). I
4931 suspect you're not running on Unix.
4933 =item "-T" is on the #! line, it must also be used on the command line
4935 (X) The #! line (or local equivalent) in a Perl script contains
4936 the B<-T> option (or the B<-t> option), but Perl was not invoked with
4937 B<-T> in its command line. This is an error because, by the time
4938 Perl discovers a B<-T> in a script, it's too late to properly taint
4939 everything from the environment. So Perl gives up.
4941 If the Perl script is being executed as a command using the #!
4942 mechanism (or its local equivalent), this error can usually be
4943 fixed by editing the #! line so that the B<-%c> option is a part of
4944 Perl's first argument: e.g. change C<perl -n -%c> to C<perl -%c -n>.
4946 If the Perl script is being executed as C<perl scriptname>, then the
4947 B<-%c> option must appear on the command line: C<perl -%c scriptname>.
4949 =item To%s: illegal mapping '%s'
4951 (F) You tried to define a customized To-mapping for lc(), lcfirst,
4952 uc(), or ucfirst() (or their string-inlined versions), but you
4953 specified an illegal mapping.
4954 See L<perlunicode/"User-Defined Character Properties">.
4956 =item Too deeply nested ()-groups
4958 (F) Your template contains ()-groups with a ridiculously deep nesting level.
4960 =item Too few args to syscall
4962 (F) There has to be at least one argument to syscall() to specify the
4963 system call to call, silly dilly.
4965 =item Too late for "-%s" option
4967 (X) The #! line (or local equivalent) in a Perl script contains the
4968 B<-M>, B<-m> or B<-C> option.
4970 In the case of B<-M> and B<-m>, this is an error because those options
4971 are not intended for use inside scripts. Use the C<use> pragma instead.
4973 The B<-C> option only works if it is specified on the command line as
4974 well (with the same sequence of letters or numbers following). Either
4975 specify this option on the command line, or, if your system supports
4976 it, make your script executable and run it directly instead of passing
4979 =item Too late to run %s block
4981 (W void) A CHECK or INIT block is being defined during run time proper,
4982 when the opportunity to run them has already passed. Perhaps you are
4983 loading a file with C<require> or C<do> when you should be using C<use>
4984 instead. Or perhaps you should put the C<require> or C<do> inside a
4987 =item Too many args to syscall
4989 (F) Perl supports a maximum of only 14 args to syscall().
4991 =item Too many arguments for %s
4993 (F) The function requires fewer arguments than you specified.
4997 (A) You've accidentally run your script through B<csh> instead of Perl.
4998 Check the #! line, or manually feed your script into Perl yourself.
5002 (A) You've accidentally run your script through B<csh> instead of Perl.
5003 Check the #! line, or manually feed your script into Perl yourself.
5005 =item Trailing \ in regex m/%s/
5007 (F) The regular expression ends with an unbackslashed backslash.
5008 Backslash it. See L<perlre>.
5010 =item Trailing white-space in a charnames alias definition is deprecated
5012 (D) You defined a character name which ended in a space character.
5013 Remove the trailing space(s). Usually these names are defined in the
5014 C<:alias> import argument to C<use charnames>, but they could be defined
5015 by a translator installed into C<$^H{charnames}>.
5016 See L<charnames/CUSTOM ALIASES>.
5018 =item Transliteration pattern not terminated
5020 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
5021 or y/// or y[][] construct. Missing the leading C<$> from variables
5022 C<$tr> or C<$y> may cause this error.
5024 =item Transliteration replacement not terminated
5026 (F) The lexer couldn't find the final delimiter of a tr///, tr[][],
5027 y/// or y[][] construct.
5029 =item '%s' trapped by operation mask
5031 (F) You tried to use an operator from a Safe compartment in which it's
5032 disallowed. See L<Safe>.
5034 =item truncate not implemented
5036 (F) Your machine doesn't implement a file truncation mechanism that
5037 Configure knows about.
5039 =item Type of arg %d to &CORE::%s must be %s
5041 (F) The subroutine in question in the CORE package requires its argument
5042 to be a hard reference to data of the specified type. Overloading is
5043 ignored, so a reference to an object that is not the specified type, but
5044 nonetheless has overloading to handle it, will still not be accepted.
5046 =item Type of arg %d to %s must be %s (not %s)
5048 (F) This function requires the argument in that position to be of a
5049 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
5050 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
5051 {EXPR} forms as an explicit dereference. See L<perlref>.
5053 =item Type of argument to %s must be unblessed hashref or arrayref
5055 (F) You called C<keys>, C<values> or C<each> with a scalar argument that
5056 was not a reference to an unblessed hash or array.
5058 =item umask not implemented
5060 (F) Your machine doesn't implement the umask function and you tried to
5061 use it to restrict permissions for yourself (EXPR & 0700).
5063 =item Unbalanced context: %d more PUSHes than POPs
5065 (S internal) The exit code detected an internal inconsistency in how
5066 many execution contexts were entered and left.
5068 =item Unbalanced saves: %d more saves than restores
5070 (S internal) The exit code detected an internal inconsistency in how
5071 many values were temporarily localized.
5073 =item Unbalanced scopes: %d more ENTERs than LEAVEs
5075 (S internal) The exit code detected an internal inconsistency in how
5076 many blocks were entered and left.
5078 =item Unbalanced string table refcount: (%d) for "%s"
5080 (S internal) On exit, Perl found some strings remaining in the shared
5081 string table used for copy on write and for hash keys. The entries
5082 should have been freed, so this indicates a bug somewhere.
5084 =item Unbalanced tmps: %d more allocs than frees
5086 (S internal) The exit code detected an internal inconsistency in how
5087 many mortal scalars were allocated and freed.
5089 =item Undefined format "%s" called
5091 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5092 another package? See L<perlform>.
5094 =item Undefined sort subroutine "%s" called
5096 (F) The sort comparison routine specified doesn't seem to exist.
5097 Perhaps it's in a different package? See L<perlfunc/sort>.
5099 =item Undefined subroutine &%s called
5101 (F) The subroutine indicated hasn't been defined, or if it was, it has
5102 since been undefined.
5104 =item Undefined subroutine called
5106 (F) The anonymous subroutine you're trying to call hasn't been defined,
5107 or if it was, it has since been undefined.
5109 =item Undefined subroutine in sort
5111 (F) The sort comparison routine specified is declared but doesn't seem
5112 to have been defined yet. See L<perlfunc/sort>.
5114 =item Undefined top format "%s" called
5116 (F) The format indicated doesn't seem to exist. Perhaps it's really in
5117 another package? See L<perlform>.
5119 =item Undefined value assigned to typeglob
5121 (W misc) An undefined value was assigned to a typeglob, a la
5122 C<*foo = undef>. This does nothing. It's possible that you really mean
5125 =item %s: Undefined variable
5127 (A) You've accidentally run your script through B<csh> instead of Perl.
5128 Check the #! line, or manually feed your script into Perl yourself.
5130 =item unexec of %s into %s failed!
5132 (F) The unexec() routine failed for some reason. See your local FSF
5133 representative, who probably put it there in the first place.
5135 =item Unexpected constant lvalue entersub entry via type/targ %d:%d
5137 (P) When compiling a subroutine call in lvalue context, Perl failed an
5138 internal consistency check. It encountered a malformed op tree.
5140 =item Unicode non-character U+%X is illegal for open interchange
5142 (S utf8, nonchar) Certain codepoints, such as U+FFFE and U+FFFF, are
5143 defined by the Unicode standard to be non-characters. Those are
5144 legal codepoints, but are reserved for internal use; so, applications
5145 shouldn't attempt to exchange them. If you know what you are doing
5146 you can turn off this warning by C<no warnings 'nonchar';>.
5148 =item Unicode surrogate U+%X is illegal in UTF-8
5150 (S utf8, surrogate) You had a UTF-16 surrogate in a context where they are
5151 not considered acceptable. These code points, between U+D800 and
5152 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
5153 internally allows all unsigned integer code points (up to the size limit
5154 available on your platform), including surrogates. But these can cause
5155 problems when being input or output, which is likely where this message
5156 came from. If you really really know what you are doing you can turn
5157 off this warning by C<no warnings 'surrogate';>.
5159 =item Unknown BYTEORDER
5161 (F) There are no byte-swapping functions for a machine with this byte
5164 =item Unknown charname '%s'
5166 (F) The name you used inside C<\N{}> is unknown to Perl. Check the
5167 spelling. You can say C<use charnames ":loose"> to not have to be
5168 so precise about spaces, hyphens, and capitalization on standard Unicode
5169 names. (Any custom aliases that have been created must be specified
5170 exactly, regardless of whether C<:loose> is used or not.) This error may
5171 also happen if the C<\N{}> is not in the scope of the corresponding
5172 C<S<use charnames>>.
5176 (P) Perl was about to print an error message in C<$@>, but the C<$@> variable
5177 did not exist, even after an attempt to create it.
5179 =item Unknown open() mode '%s'
5181 (F) The second argument of 3-argument open() is not among the list
5182 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
5183 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
5185 =item Unknown PerlIO layer "%s"
5187 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
5188 system. (Layers take care of transforming data between external and
5189 internal representations.) Note that some layers, such as C<mmap>,
5190 are not supported in all environments. If your program didn't
5191 explicitly request the failing operation, it may be the result of the
5192 value of the environment variable PERLIO.
5194 =item Unknown process %x sent message to prime_env_iter: %s
5196 (P) An error peculiar to VMS. Perl was reading values for %ENV before
5197 iterating over it, and someone else stuck a message in the stream of
5198 data Perl expected. Someone's very confused, or perhaps trying to
5199 subvert Perl's population of %ENV for nefarious purposes.
5201 =item Unknown "re" subpragma '%s' (known ones are: %s)
5203 (W) You tried to use an unknown subpragma of the "re" pragma.
5205 =item Unknown regex modifier "%s"
5207 (F) Alphanumerics immediately following the closing delimiter
5208 of a regular expression pattern are interpreted by Perl as modifier
5209 flags for the regex. One of the ones you specified is invalid. One way
5210 this can happen is if you didn't put in white space between the end of
5211 the regex and a following alphanumeric operator:
5213 if ($a =~ /foo/and $bar == 3) { ... }
5215 The C<"a"> is a valid modifier flag, but the C<"n"> is not, and raises
5216 this error. Likely what was meant instead was:
5218 if ($a =~ /foo/ and $bar == 3) { ... }
5220 =item Unknown switch condition (?(%s in regex; marked by <-- HERE in m/%s/
5222 (F) The condition part of a (?(condition)if-clause|else-clause) construct
5223 is not known. The condition must be one of the following:
5225 (1) (2) ... true if 1st, 2nd, etc., capture matched
5226 (<NAME>) ('NAME') true if named capture matched
5227 (?=...) (?<=...) true if subpattern matches
5228 (?!...) (?<!...) true if subpattern fails to match
5229 (?{ CODE }) true if code returns a true value
5230 (R) true if evaluating inside recursion
5231 (R1) (R2) ... true if directly inside capture group 1, 2, etc.
5232 (R&NAME) true if directly inside named capture
5233 (DEFINE) always false; for defining named subpatterns
5235 The <-- HERE shows whereabouts in the regular expression the problem was
5236 discovered. See L<perlre>.
5238 =item Unknown Unicode option letter '%c'
5240 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5241 of the C<-C> switch for the list of known options.
5243 =item Unknown Unicode option value %x
5245 (F) You specified an unknown Unicode option. See L<perlrun> documentation
5246 of the C<-C> switch for the list of known options.
5248 =item Unknown verb pattern '%s' in regex; marked by <-- HERE in m/%s/
5250 (F) You either made a typo or have incorrectly put a C<*> quantifier
5251 after an open brace in your pattern. Check the pattern and review
5252 L<perlre> for details on legal verb patterns.
5254 =item Unknown warnings category '%s'
5256 (F) An error issued by the C<warnings> pragma. You specified a warnings
5257 category that is unknown to perl at this point.
5259 Note that if you want to enable a warnings category registered by a
5260 module (e.g. C<use warnings 'File::Find'>), you must have loaded this
5263 =item Unmatched [ in regex; marked by <-- HERE in m/%s/
5265 (F) The brackets around a character class must match. If you wish to
5266 include a closing bracket in a character class, backslash it or put it
5267 first. The <-- HERE shows whereabouts in the regular expression the
5268 problem was discovered. See L<perlre>.
5270 =item Unmatched ( in regex; marked by <-- HERE in m/%s/
5272 =item Unmatched ) in regex; marked by <-- HERE in m/%s/
5274 (F) Unbackslashed parentheses must always be balanced in regular
5275 expressions. If you're a vi user, the % key is valuable for finding
5276 the matching parenthesis. The <-- HERE shows whereabouts in the
5277 regular expression the problem was discovered. See L<perlre>.
5279 =item Unmatched right %s bracket
5281 (F) The lexer counted more closing curly or square brackets than opening
5282 ones, so you're probably missing a matching opening bracket. As a
5283 general rule, you'll find the missing one (so to speak) near the place
5284 you were last editing.
5286 =item Unquoted string "%s" may clash with future reserved word
5288 (W reserved) You used a bareword that might someday be claimed as a
5289 reserved word. It's best to put such a word in quotes, or capitalize it
5290 somehow, or insert an underbar into it. You might also declare it as a
5293 =item Unrecognized character %s; marked by <-- HERE after %s near column %d
5295 (F) The Perl parser has no idea what to do with the specified character
5296 in your Perl script (or eval) near the specified column. Perhaps you tried
5297 to run a compressed script, a binary program, or a directory as a Perl program.
5299 =item Unrecognized escape \%c in character class passed through in regex;
5300 marked by <-- HERE in m/%s/
5302 (W regexp) You used a backslash-character combination which is not
5303 recognized by Perl inside character classes. The character was
5304 understood literally, but this may change in a future version of Perl.
5305 The <-- HERE shows whereabouts in the regular expression the
5306 escape was discovered.
5308 =item Unrecognized escape \%c passed through
5310 (W misc) You used a backslash-character combination which is not
5311 recognized by Perl. The character was understood literally, but this may
5312 change in a future version of Perl.
5314 =item Unrecognized escape \%s passed through in regex; marked by <-- HERE in m/%s/
5316 (W regexp) You used a backslash-character combination which is not
5317 recognized by Perl. The character(s) were understood literally, but
5318 this may change in a future version of Perl. The <-- HERE shows
5319 whereabouts in the regular expression the escape was discovered.
5321 =item Unrecognized signal name "%s"
5323 (F) You specified a signal name to the kill() function that was not
5324 recognized. Say C<kill -l> in your shell to see the valid signal names
5327 =item Unrecognized switch: -%s (-h will show valid options)
5329 (F) You specified an illegal option to Perl. Don't do that. (If you
5330 think you didn't do that, check the #! line to see if it's supplying the
5331 bad switch on your behalf.)
5333 =item Unsuccessful %s on filename containing newline
5335 (W newline) A file operation was attempted on a filename, and that
5336 operation failed, PROBABLY because the filename contained a newline,
5337 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
5339 =item Unsupported directory function "%s" called
5341 (F) Your machine doesn't support opendir() and readdir().
5343 =item Unsupported function %s
5345 (F) This machine doesn't implement the indicated function, apparently.
5346 At least, Configure doesn't think so.
5348 =item Unsupported function fork
5350 (F) Your version of executable does not support forking.
5352 Note that under some systems, like OS/2, there may be different flavors
5353 of Perl executables, some of which may support fork, some not. Try
5354 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
5356 =item Unsupported script encoding %s
5358 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
5359 declares it to be in a Unicode encoding that Perl cannot read.
5361 =item Unsupported socket function "%s" called
5363 (F) Your machine doesn't support the Berkeley socket mechanism, or at
5364 least that's what Configure thought.
5366 =item Unterminated attribute list
5368 (F) The lexer found something other than a simple identifier at the
5369 start of an attribute, and it wasn't a semicolon or the start of a
5370 block. Perhaps you terminated the parameter list of the previous
5371 attribute too soon. See L<attributes>.
5373 =item Unterminated attribute parameter in attribute list
5375 (F) The lexer saw an opening (left) parenthesis character while parsing
5376 an attribute list, but the matching closing (right) parenthesis
5377 character was not found. You may need to add (or remove) a backslash
5378 character to get your parentheses to balance. See L<attributes>.
5380 =item Unterminated compressed integer
5382 (F) An argument to unpack("w",...) was incompatible with the BER
5383 compressed integer format and could not be converted to an integer.
5384 See L<perlfunc/pack>.
5386 =item Unterminated delimiter for here document
5388 (F) This message occurs when a here document label has an initial
5389 quotation mark but the final quotation mark is missing. Perhaps
5398 =item Unterminated \g{...} pattern in regex; marked by <-- HERE in m/%s/
5400 (F) You missed a close brace on a \g{..} pattern (group reference) in
5401 a regular expression. Fix the pattern and retry.
5403 =item Unterminated <> operator
5405 (F) The lexer saw a left angle bracket in a place where it was expecting
5406 a term, so it's looking for the corresponding right angle bracket, and
5407 not finding it. Chances are you left some needed parentheses out
5408 earlier in the line, and you really meant a "less than".
5410 =item Unterminated verb pattern argument in regex; marked by <-- HERE in m/%s/
5412 (F) You used a pattern of the form C<(*VERB:ARG)> but did not terminate
5413 the pattern with a C<)>. Fix the pattern and retry.
5415 =item Unterminated verb pattern in regex; marked by <-- HERE in m/%s/
5417 (F) You used a pattern of the form C<(*VERB)> but did not terminate
5418 the pattern with a C<)>. Fix the pattern and retry.
5420 =item untie attempted while %d inner references still exist
5422 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
5423 still valid when C<untie> was called.
5425 =item Usage: POSIX::%s(%s)
5427 (F) You called a POSIX function with incorrect arguments.
5428 See L<POSIX/FUNCTIONS> for more information.
5430 =item Usage: Win32::%s(%s)
5432 (F) You called a Win32 function with incorrect arguments.
5433 See L<Win32> for more information.
5435 =item $[ used in %s (did you mean $] ?)
5437 (W syntax) You used C<$[> in a comparison, such as:
5443 You probably meant to use C<$]> instead. C<$[> is the base for indexing
5444 arrays. C<$]> is the Perl version number in decimal.
5446 =item Useless assignment to a temporary
5448 (W misc) You assigned to an lvalue subroutine, but what
5449 the subroutine returned was a temporary scalar about to
5450 be discarded, so the assignment had no effect.
5452 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in
5455 (W regexp) You have used an internal modifier such as (?-o) that has no
5456 meaning unless removed from the entire regexp:
5458 if ($string =~ /(?-o)$pattern/o) { ... }
5462 if ($string =~ /$pattern/) { ... }
5464 The <-- HERE shows whereabouts in the regular expression the problem was
5465 discovered. See L<perlre>.
5467 =item Useless localization of %s
5469 (W syntax) The localization of lvalues such as C<local($x=10)> is legal,
5470 but in fact the local() currently has no effect. This may change at
5471 some point in the future, but in the meantime such code is discouraged.
5473 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
5475 (W regexp) You have used an internal modifier such as (?o) that has no
5476 meaning unless applied to the entire regexp:
5478 if ($string =~ /(?o)$pattern/) { ... }
5482 if ($string =~ /$pattern/o) { ... }
5484 The <-- HERE shows whereabouts in the regular expression the problem was
5485 discovered. See L<perlre>.
5487 =item Useless use of /d modifier in transliteration operator
5489 (W misc) You have used the /d modifier where the searchlist has the
5490 same length as the replacelist. See L<perlop> for more information
5491 about the /d modifier.
5493 =item Useless use of '\'; doesn't escape metacharacter '%c'
5495 (D deprecated) You wrote a regular expression pattern something like
5501 s[foo\[a-z\]bar][baz]
5503 The interior braces, square brackets, and parentheses are treated as
5504 metacharacters even though they are backslashed; instead write:
5511 The backslashes have no effect when a regular expression pattern is
5512 delimitted by C<{}>, C<[]>, or C<()>, which ordinarily are
5513 metacharacters, and the delimiters are also used, paired, within the
5514 interior of the pattern. It is planned that a future Perl release will
5515 change the meaning of constructs like these so that the backslashes
5516 will have an effect, so remove them from your code.
5518 =item Useless use of \E
5520 (W misc) You have a \E in a double-quotish string without a C<\U>,
5521 C<\L> or C<\Q> preceding it.
5523 =item Useless use of %s in void context
5525 (W void) You did something without a side effect in a context that does
5526 nothing with the return value, such as a statement that doesn't return a
5527 value from a block, or the left side of a scalar comma operator. Very
5528 often this points not to stupidity on your part, but a failure of Perl
5529 to parse your program the way you thought it would. For example, you'd
5530 get this if you mixed up your C precedence with Python precedence and
5535 when you meant to say
5537 ($one, $two) = (1, 2);
5539 Another common error is to use ordinary parentheses to construct a list
5540 reference when you should be using square or curly brackets, for
5545 when you should have said
5549 The square brackets explicitly turn a list value into a scalar value,
5550 while parentheses do not. So when a parenthesized list is evaluated in
5551 a scalar context, the comma is treated like C's comma operator, which
5552 throws away the left argument, which is not what you want. See
5553 L<perlref> for more on this.
5555 This warning will not be issued for numerical constants equal to 0 or 1
5556 since they are often used in statements like
5558 1 while sub_with_side_effects();
5560 String constants that would normally evaluate to 0 or 1 are warned
5563 =item Useless use of "re" pragma
5565 (W) You did C<use re;> without any arguments. That isn't very useful.
5567 =item Useless use of sort in scalar context
5569 (W void) You used sort in scalar context, as in :
5573 This is not very useful, and perl currently optimizes this away.
5575 =item Useless use of %s with no values
5577 (W syntax) You used the push() or unshift() function with no arguments
5578 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
5579 usually have any effect on the array, so is completely useless. It's
5580 possible in principle that push(@tied_array) could have some effect
5581 if the array is tied to a class which implements a PUSH method. If so,
5582 you can write it as C<push(@tied_array,())> to avoid this warning.
5584 =item "use" not allowed in expression
5586 (F) The "use" keyword is recognized and executed at compile time, and
5587 returns no useful value. See L<perlmod>.
5589 =item Use of assignment to $[ is deprecated
5591 (D deprecated) The C<$[> variable (index of the first element in an array)
5592 is deprecated. See L<perlvar/"$[">.
5594 =item Use of bare << to mean <<"" is deprecated
5596 (D deprecated) You are now encouraged to use the explicitly quoted
5597 form if you wish to use an empty line as the terminator of the here-document.
5599 =item Use of comma-less variable list is deprecated
5601 (D deprecated) The values you give to a format should be
5602 separated by commas, not just aligned on a line.
5604 =item Use of chdir('') or chdir(undef) as chdir() deprecated
5606 (D deprecated) chdir() with no arguments is documented to change to
5607 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
5608 behavior, but that has been deprecated. In future versions they
5611 Be careful to check that what you pass to chdir() is defined and not
5612 blank, else you might find yourself in your home directory.
5614 =item Use of /c modifier is meaningless in s///
5616 (W regexp) You used the /c modifier in a substitution. The /c
5617 modifier is not presently meaningful in substitutions.
5619 =item Use of /c modifier is meaningless without /g
5621 (W regexp) You used the /c modifier with a regex operand, but didn't
5622 use the /g modifier. Currently, /c is meaningful only when /g is
5623 used. (This may change in the future.)
5625 =item Use of := for an empty attribute list is not allowed
5627 (F) The construction C<my $x := 42> used to parse as equivalent to
5628 C<my $x : = 42> (applying an empty attribute list to C<$x>).
5629 This construct was deprecated in 5.12.0, and has now been made a syntax
5630 error, so C<:=> can be reclaimed as a new operator in the future.
5632 If you need an empty attribute list, for example in a code generator, add
5633 a space before the C<=>.
5635 =item Use of freed value in iteration
5637 (F) Perhaps you modified the iterated array within the loop?
5638 This error is typically caused by code like the following:
5641 @a = () for (1,2,@a);
5643 You are not supposed to modify arrays while they are being iterated over.
5644 For speed and efficiency reasons, Perl internally does not do full
5645 reference-counting of iterated items, hence deleting such an item in the
5646 middle of an iteration causes Perl to see a freed value.
5648 =item Use of *glob{FILEHANDLE} is deprecated
5650 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
5651 to access the filehandle slot within a typeglob.
5653 =item Use of /g modifier is meaningless in split
5655 (W regexp) You used the /g modifier on the pattern for a C<split>
5656 operator. Since C<split> always tries to match the pattern
5657 repeatedly, the C</g> has no effect.
5659 =item Use of "goto" to jump into a construct is deprecated
5661 (D deprecated) Using C<goto> to jump from an outer scope into an inner
5662 scope is deprecated and should be avoided.
5664 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
5666 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD>
5667 subroutines are looked up as methods (using the C<@ISA> hierarchy)
5668 even when the subroutines to be autoloaded were called as plain
5669 functions (e.g. C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or
5670 C<< $obj->bar() >>).
5672 This bug will be rectified in future by using method lookup only for
5673 methods' C<AUTOLOAD>s. However, there is a significant base of existing
5674 code that may be using the old behavior. So, as an interim step, Perl
5675 currently issues an optional warning when non-methods use inherited
5678 The simple rule is: Inheritance will not work when autoloading
5679 non-methods. The simple fix for old code is: In any module that used
5680 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
5681 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
5684 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
5685 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
5686 C<use AutoLoader 'AUTOLOAD';>.
5688 =item Use of %s in printf format not supported
5690 (F) You attempted to use a feature of printf that is accessible from
5691 only C. This usually means there's a better way to do it in Perl.
5693 =item Use of %s is deprecated
5695 (D deprecated) The construct indicated is no longer recommended for use,
5696 generally because there's a better way to do it, and also because the
5697 old way has bad side effects.
5699 =item Use of -l on filehandle %s
5701 (W io) A filehandle represents an opened file, and when you opened the file
5702 it already went past any symlink you are presumably trying to look for.
5703 The operation returned C<undef>. Use a filename instead.
5705 =item Use of %s on a handle without * is deprecated
5707 (D deprecated) You used C<tie>, C<tied> or C<untie> on a scalar but that scalar
5708 happens to hold a typeglob, which means its filehandle will be tied. If
5709 you mean to tie a handle, use an explicit * as in C<tie *$handle>.
5711 This was a long-standing bug that was removed in Perl 5.16, as there was
5712 no way to tie the scalar itself when it held a typeglob, and no way to
5713 untie a scalar that had had a typeglob assigned to it. If you see this
5714 message, you must be using an older version.
5716 =item Use of ?PATTERN? without explicit operator is deprecated
5718 (D deprecated) You have written something like C<?\w?>, for a regular
5719 expression that matches only once. Starting this term directly with
5720 the question mark delimiter is now deprecated, so that the question mark
5721 will be available for use in new operators in the future. Write C<m?\w?>
5722 instead, explicitly using the C<m> operator: the question mark delimiter
5723 still invokes match-once behaviour.
5725 =item Use of reference "%s" as array index
5727 (W misc) You tried to use a reference as an array index; this probably
5728 isn't what you mean, because references in numerical context tend
5729 to be huge numbers, and so usually indicates programmer error.
5731 If you really do mean it, explicitly numify your reference, like so:
5732 C<$array[0+$ref]>. This warning is not given for overloaded objects,
5733 however, because you can overload the numification and stringification
5734 operators and then you presumably know what you are doing.
5736 =item Use of tainted arguments in %s is deprecated
5738 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
5739 arguments and at least one of them is tainted. This used to be allowed
5740 but will become a fatal error in a future version of perl. Untaint your
5741 arguments. See L<perlsec>.
5743 =item Use of uninitialized value%s
5745 (W uninitialized) An undefined value was used as if it were already
5746 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
5747 To suppress this warning assign a defined value to your variables.
5749 To help you figure out what was undefined, perl will try to tell you
5750 the name of the variable (if any) that was undefined. In some cases
5751 it cannot do this, so it also tells you what operation you used the
5752 undefined value in. Note, however, that perl optimizes your program
5753 anid the operation displayed in the warning may not necessarily appear
5754 literally in your program. For example, C<"that $foo"> is usually
5755 optimized into C<"that " . $foo>, and the warning will refer to the
5756 C<concatenation (.)> operator, even though there is no C<.> in
5759 =item Using a hash as a reference is deprecated
5761 (D deprecated) You tried to use a hash as a reference, as in
5762 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
5763 used to allow this syntax, but shouldn't have. It is now
5764 deprecated, and will be removed in a future version.
5766 =item Using an array as a reference is deprecated
5768 (D deprecated) You tried to use an array as a reference, as in
5769 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
5770 allow this syntax, but shouldn't have. It is now deprecated,
5771 and will be removed in a future version.
5773 =item Using just the first character returned by \N{} in character class in
5774 regex; marked by <-- HERE in m/%s/
5776 (W regexp) A charnames handler may return a sequence of more than one
5777 character. Currently all but the first one are discarded when used in
5778 a regular expression pattern bracketed character class.
5780 =item Using !~ with %s doesn't make sense
5782 (F) Using the C<!~> operator with C<s///r>, C<tr///r> or C<y///r> is
5783 currently reserved for future use, as the exact behaviour has not
5784 been decided. (Simply returning the boolean opposite of the
5785 modified string is usually not particularly useful.)
5787 =item UTF-16 surrogate U+%X
5789 (S utf8, surrogate) You had a UTF-16 surrogate in a context where they are
5790 not considered acceptable. These code points, between U+D800 and
5791 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
5792 internally allows all unsigned integer code points (up to the size limit
5793 available on your platform), including surrogates. But these can cause
5794 problems when being input or output, which is likely where this message
5795 came from. If you really really know what you are doing you can turn
5796 off this warning by C<no warnings 'surrogate';>.
5798 =item Value of %s can be "0"; test with defined()
5800 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
5801 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
5802 can return a value of "0"; that would make the conditional expression
5803 false, which is probably not what you intended. When using these
5804 constructs in conditional expressions, test their values with the
5805 C<defined> operator.
5807 =item Value of CLI symbol "%s" too long
5809 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
5810 %ENV element from a CLI symbol table, and found a resultant string
5811 longer than 1024 characters. The return value has been truncated to
5814 =item Variable "%s" is not available
5816 (W closure) During compilation, an inner named subroutine or eval is
5817 attempting to capture an outer lexical that is not currently available.
5818 This can happen for one of two reasons. First, the outer lexical may be
5819 declared in an outer anonymous subroutine that has not yet been created.
5820 (Remember that named subs are created at compile time, while anonymous
5821 subs are created at run-time.) For example,
5823 sub { my $a; sub f { $a } }
5825 At the time that f is created, it can't capture the current value of $a,
5826 since the anonymous subroutine hasn't been created yet. Conversely,
5827 the following won't give a warning since the anonymous subroutine has by
5828 now been created and is live:
5830 sub { my $a; eval 'sub f { $a }' }->();
5832 The second situation is caused by an eval accessing a variable that has
5833 gone out of scope, for example,
5841 Here, when the '$a' in the eval is being compiled, f() is not currently being
5842 executed, so its $a is not available for capture.
5844 =item Variable "%s" is not imported%s
5846 (S misc) With "use strict" in effect, you referred to a global variable
5847 that you apparently thought was imported from another module, because
5848 something else of the same name (usually a subroutine) is exported by
5849 that module. It usually means you put the wrong funny character on the
5850 front of your variable.
5852 =item Variable length lookbehind not implemented in regex m/%s/
5854 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
5855 known at compile time. See L<perlre>.
5857 =item "%s" variable %s masks earlier declaration in same %s
5859 (W misc) A "my", "our" or "state" variable has been redeclared in the
5860 current scope or statement, effectively eliminating all access to the
5861 previous instance. This is almost always a typographical error. Note
5862 that the earlier variable will still exist until the end of the scope
5863 or until all closure references to it are destroyed.
5865 =item Variable syntax
5867 (A) You've accidentally run your script through B<csh> instead
5868 of Perl. Check the #! line, or manually feed your script into
5871 =item Variable "%s" will not stay shared
5873 (W closure) An inner (nested) I<named> subroutine is referencing a
5874 lexical variable defined in an outer named subroutine.
5876 When the inner subroutine is called, it will see the value of
5877 the outer subroutine's variable as it was before and during the *first*
5878 call to the outer subroutine; in this case, after the first call to the
5879 outer subroutine is complete, the inner and outer subroutines will no
5880 longer share a common value for the variable. In other words, the
5881 variable will no longer be shared.
5883 This problem can usually be solved by making the inner subroutine
5884 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
5885 reference variables in outer subroutines are created, they
5886 are automatically rebound to the current values of such variables.
5888 =item vector argument not supported with alpha versions
5890 (S printf) The %vd (s)printf format does not support version objects
5893 =item Verb pattern '%s' has a mandatory argument in regex; marked by <-- HERE
5896 (F) You used a verb pattern that requires an argument. Supply an
5897 argument or check that you are using the right verb.
5899 =item Verb pattern '%s' may not have an argument in regex; marked by <-- HERE
5902 (F) You used a verb pattern that is not allowed an argument. Remove the
5903 argument or check that you are using the right verb.
5905 =item Version number must be a constant number
5907 (P) The attempt to translate a C<use Module n.n LIST> statement into
5908 its equivalent C<BEGIN> block found an internal inconsistency with
5911 =item Version string '%s' contains invalid data; ignoring: '%s'
5913 (W misc) The version string contains invalid characters at the end, which
5916 =item Warning: something's wrong
5918 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
5919 you called it with no args and C<$@> was empty.
5921 =item Warning: unable to close filehandle %s properly
5923 (S) The implicit close() done by an open() got an error indication on
5924 the close(). This usually indicates your file system ran out of disk
5927 =item Warning: Use of "%s" without parentheses is ambiguous
5929 (S ambiguous) You wrote a unary operator followed by something that
5930 looks like a binary operator that could also have been interpreted as a
5931 term or unary operator. For instance, if you know that the rand
5932 function has a default argument of 1.0, and you write
5936 you may THINK you wrote the same thing as
5940 but in actual fact, you got
5944 So put in parentheses to say what you really mean.
5946 =item Wide character in %s
5948 (S utf8) Perl met a wide character (>255) when it wasn't expecting
5949 one. This warning is by default on for I/O (like print). The easiest
5950 way to quiet this warning is simply to add the C<:utf8> layer to the
5951 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
5952 warning is to add C<no warnings 'utf8';> but that is often closer to
5953 cheating. In general, you are supposed to explicitly mark the
5954 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
5956 =item Within []-length '%c' not allowed
5958 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]>
5959 only if C<TEMPLATE> always matches the same amount of packed bytes that
5960 can be determined from the template alone. This is not possible if
5961 it contains any of the codes @, /, U, u, w or a *-length. Redesign
5964 =item write() on closed filehandle %s
5966 (W closed) The filehandle you're writing to got itself closed sometime
5967 before now. Check your control flow.
5969 =item %s "\x%X" does not map to Unicode
5971 (F) When reading in different encodings Perl tries to map everything
5972 into Unicode characters. The bytes you read in are not legal in
5973 this encoding, for example
5975 utf8 "\xE4" does not map to Unicode
5977 if you try to read in the a-diaereses Latin-1 as UTF-8.
5979 =item 'X' outside of string
5981 (F) You had a (un)pack template that specified a relative position before
5982 the beginning of the string being (un)packed. See L<perlfunc/pack>.
5984 =item 'x' outside of string in unpack
5986 (F) You had a pack template that specified a relative position after
5987 the end of the string being unpacked. See L<perlfunc/pack>.
5989 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
5991 (F) And you probably never will, because you probably don't have the
5992 sources to your kernel, and your vendor probably doesn't give a rip
5993 about what you want. Your best bet is to put a setuid C wrapper around
5996 =item You need to quote "%s"
5998 (W syntax) You assigned a bareword as a signal handler name.
5999 Unfortunately, you already have a subroutine of that name declared,
6000 which means that Perl 5 will try to call the subroutine when the
6001 assignment is executed, which is probably not what you want. (If it IS
6002 what you want, put an & in front.)
6004 =item Your random numbers are not that random
6006 (F) When trying to initialise the random seed for hashes, Perl could
6007 not get any randomness out of your system. This usually indicates
6008 Something Very Wrong.
6014 L<warnings>, L<perllexwarn>, L<diagnostics>.