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
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 overloaded argument to %s resolved as %s
81 (W ambiguous) You called C<keys>, C<values> or C<each> on an object that had
82 overloading of C<%{}> or C<@{}> or both. In such a case, the object is
83 dereferenced according to its overloading, not its underlying reference type.
84 The warning is issued when C<%{}> overloading exists on a blessed arrayref,
85 when C<@{}> overloading exists on a blessed hashref, or when both overloadings
86 are defined (in which case C<%{}> is used). You can force the interpretation
87 of the object by explicitly dereferencing it as an array or hash instead of
88 passing the object itself to C<keys>, C<values> or C<each>.
90 =item Ambiguous range in transliteration operator
92 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
93 all. To include a C<-> character in a transliteration, put it either
94 first or last. (In the past, C<tr/a-z-0//> was synonymous with
95 C<tr/a-y//>, which was probably not what you would have expected.)
97 =item Ambiguous use of %s resolved as %s
99 (W ambiguous)(S) You said something that may not be interpreted the way
100 you thought. Normally it's pretty easy to disambiguate it by supplying
101 a missing quote, operator, parenthesis pair or declaration.
103 =item Ambiguous use of %c resolved as operator %c
105 (W ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
106 bitwise and, and multiplication) I<and> initial special characters
107 (denoting hashes, subroutines and typeglobs), and you said something
108 like C<*foo * foo> that might be interpreted as either of them. We
109 assumed you meant the infix operator, but please try to make it more
110 clear -- in the example given, you might write C<*foo * foo()> if you
111 really meant to multiply a glob by the result of calling a function.
113 =item Ambiguous use of %c{%s} resolved to %c%s
115 (W ambiguous) You wrote something like C<@{foo}>, which might be
116 asking for the variable C<@foo>, or it might be calling a function
117 named foo, and dereferencing it as an array reference. If you wanted
118 the varable, you can just write C<@foo>. If you wanted to call the
119 function, write C<@{foo()}> ... or you could just not have a variable
120 and a function with the same name, and save yourself a lot of trouble.
122 =item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
124 =item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
126 (W ambiguous) You wrote something like C<${foo[2]}> (where foo
127 represents the name of a Perl keyword), which might be looking for
128 element number 2 of the array named C<@foo>, in which case please write
129 C<$foo[2]>, or you might have meant to pass an anonymous arrayref to
130 the function named foo, and then do a scalar deref on the value it
131 returns. If you meant that, write C<${foo([2])}>.
133 In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
134 to disambiguate between array subscripts and character classes.
135 C</$length[2345]/>, for instance, will be interpreted as C<$length>
136 followed by the character class C<[2345]>. If an array subscript is what
137 you want, you can avoid the warning by changing C</${length[2345]}/>
138 to the unsightly C</${\$length[2345]}/>, by renaming your array to
139 something that does not coincide with a built-in keyword, or by
140 simply turning off warnings with C<no warnings 'ambiguous';>.
142 =item Ambiguous use of -%s resolved as -&%s()
144 (W ambiguous) You wrote something like C<-foo>, which might be the
145 string C<"-foo">, or a call to the function C<foo>, negated. If you meant
146 the string, just write C<"-foo">. If you meant the function call,
149 =item '|' and '<' may not both be specified on command line
151 (F) An error peculiar to VMS. Perl does its own command line
152 redirection, and found that STDIN was a pipe, and that you also tried to
153 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
155 =item '|' and '>' may not both be specified on command line
157 (F) An error peculiar to VMS. Perl does its own command line
158 redirection, and thinks you tried to redirect stdout both to a file and
159 into a pipe to another command. You need to choose one or the other,
160 though nothing's stopping you from piping into a program or Perl script
161 which 'splits' output into two streams, such as
163 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
170 =item Applying %s to %s will act on scalar(%s)
172 (W misc) The pattern match (C<//>), substitution (C<s///>), and
173 transliteration (C<tr///>) operators work on scalar values. If you apply
174 one of them to an array or a hash, it will convert the array or hash to
175 a scalar value (the length of an array, or the population info of a
176 hash) and then work on that scalar value. This is probably not what
177 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
180 =item Args must match #! line
182 (F) The setuid emulator requires that the arguments Perl was invoked
183 with match the arguments specified on the #! line. Since some systems
184 impose a one-argument limit on the #! line, try combining switches;
185 for example, turn C<-w -U> into C<-wU>.
187 =item Arg too short for msgsnd
189 (F) msgsnd() requires a string at least as long as sizeof(long).
191 =item %s argument is not a HASH or ARRAY element or a subroutine
193 (F) The argument to exists() must be a hash or array element or a
194 subroutine with an ampersand, such as:
200 =item %s argument is not a HASH or ARRAY element or slice
202 (F) The argument to delete() must be either a hash or array element,
208 or a hash or array slice, such as:
210 @foo[$bar, $baz, $xyzzy]
211 @{$ref->[12]}{"susie", "queue"}
213 =item %s argument is not a subroutine name
215 (F) The argument to exists() for C<exists &sub> must be a subroutine
216 name, and not a subroutine call. C<exists &sub()> will generate this
219 =item Argument "%s" isn't numeric%s
221 (W numeric) The indicated string was fed as an argument to an operator
222 that expected a numeric value instead. If you're fortunate the message
223 will identify which operator was so unfortunate.
225 =item Argument list not closed for PerlIO layer "%s"
227 (W layer) When pushing a layer with arguments onto the Perl I/O system you
228 forgot the ) that closes the argument list. (Layers take care of transforming
229 data between external and internal representations.) Perl stopped parsing
230 the layer list at this point and did not attempt to push this layer.
231 If your program didn't explicitly request the failing operation, it may be
232 the result of the value of the environment variable PERLIO.
234 =item Array @%s missing the @ in argument %d of %s()
236 (D deprecated) Really old Perl let you omit the @ on array names in some
237 spots. This is now heavily deprecated.
239 =item assertion botched: %s
241 (P) The malloc package that comes with Perl had an internal failure.
243 =item Assertion failed: file "%s"
245 (P) A general assertion failed. The file in question must be examined.
247 =item Assignment to both a list and a scalar
249 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
250 must either both be scalars or both be lists. Otherwise Perl won't
251 know which context to supply to the right side.
253 =item A thread exited while %d threads were running
255 (W threads)(S) When using threaded Perl, a thread (not necessarily the main
256 thread) exited while there were still other threads running.
257 Usually it's a good idea first to collect the return values of the
258 created threads by joining them, and only then to exit from the main
259 thread. See L<threads>.
261 =item Attempt to access disallowed key '%s' in a restricted hash
263 (F) The failing code has attempted to get or set a key which is not in
264 the current set of allowed keys of a restricted hash.
266 =item Attempt to bless into a reference
268 (F) The CLASSNAME argument to the bless() operator is expected to be
269 the name of the package to bless the resulting object into. You've
270 supplied instead a reference to something: perhaps you wrote
276 bless $self, ref($proto) || $proto;
278 If you actually want to bless into the stringified version
279 of the reference supplied, you need to stringify it yourself, for
282 bless $self, "$proto";
284 =item Attempt to delete disallowed key '%s' from a restricted hash
286 (F) The failing code attempted to delete from a restricted hash a key
287 which is not in its key set.
289 =item Attempt to delete readonly key '%s' from a restricted hash
291 (F) The failing code attempted to delete a key whose value has been
292 declared readonly from a restricted hash.
294 =item Attempt to free non-arena SV: 0x%x
296 (P internal) All SV objects are supposed to be allocated from arenas
297 that will be garbage collected on exit. An SV was discovered to be
298 outside any of those arenas.
300 =item Attempt to free nonexistent shared string
302 (P internal) Perl maintains a reference-counted internal table of
303 strings to optimize the storage and access of hash keys and other
304 strings. This indicates someone tried to decrement the reference count
305 of a string that can no longer be found in the table.
307 =item Attempt to free temp prematurely
309 (W debugging) Mortalized values are supposed to be freed by the
310 free_tmps() routine. This indicates that something else is freeing the
311 SV before the free_tmps() routine gets a chance, which means that the
312 free_tmps() routine will be freeing an unreferenced scalar when it does
315 =item Attempt to free unreferenced glob pointers
317 (P internal) The reference counts got screwed up on symbol aliases.
319 =item Attempt to free unreferenced scalar
321 (W internal) Perl went to decrement the reference count of a scalar to
322 see if it would go to 0, and discovered that it had already gone to 0
323 earlier, and should have been freed, and in fact, probably was freed.
324 This could indicate that SvREFCNT_dec() was called too many times, or
325 that SvREFCNT_inc() was called too few times, or that the SV was
326 mortalized when it shouldn't have been, or that memory has been
329 =item Attempt to join self
331 (F) You tried to join a thread from within itself, which is an
332 impossible task. You may be joining the wrong thread, or you may need
333 to move the join() to some other thread.
335 =item Attempt to pack pointer to temporary value
337 (W pack) You tried to pass a temporary value (like the result of a
338 function, or a computed expression) to the "p" pack() template. This
339 means the result contains a pointer to a location that could become
340 invalid anytime, even before the end of the current statement. Use
341 literals or global values as arguments to the "p" pack() template to
344 =item Attempt to reload %s aborted.
346 (F) You tried to load a file with C<use> or C<require> that failed to
347 compile once already. Perl will not try to compile this file again
348 unless you delete its entry from %INC. See L<perlfunc/require> and
351 =item Attempt to set length of freed array
353 (W) You tried to set the length of an array which has been freed. You
354 can do this by storing a reference to the scalar representing the last index
355 of an array and later assigning through that reference. For example
357 $r = do {my @a; \$#a};
360 =item Attempt to use reference as lvalue in substr
362 (W substr) You supplied a reference as the first argument to substr()
363 used as an lvalue, which is pretty strange. Perhaps you forgot to
364 dereference it first. See L<perlfunc/substr>.
366 =item Attribute "locked" is deprecated
368 (D deprecated) You have used the attributes pragma to modify the "locked"
369 attribute on a code reference. The :locked attribute is obsolete, has had no
370 effect since 5005 threads were removed, and will be removed in a future
373 =item Attribute "unique" is deprecated
375 (D deprecated) You have used the attributes pragma to modify the "unique"
376 attribute on an array, hash or scalar reference. The :unique attribute has
377 had no effect since Perl 5.8.8, and will be removed in a future release
380 =item Bad arg length for %s, is %u, should be %d
382 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
383 or shmctl(). In C parlance, the correct sizes are, respectively,
384 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
385 S<sizeof(struct shmid_ds *)>.
387 =item Bad evalled substitution pattern
389 (F) You've used the C</e> switch to evaluate the replacement for a
390 substitution, but perl found a syntax error in the code to evaluate,
391 most likely an unexpected right brace '}'.
393 =item Bad filehandle: %s
395 (F) A symbol was passed to something wanting a filehandle, but the
396 symbol has no filehandle associated with it. Perhaps you didn't do an
397 open(), or did it in another package.
399 =item Bad free() ignored
401 (S malloc) An internal routine called free() on something that had never
402 been malloc()ed in the first place. Mandatory, but can be disabled by
403 setting environment variable C<PERL_BADFREE> to 0.
405 This message can be seen quite often with DB_File on systems with "hard"
406 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
407 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
411 (P) One of the internal hash routines was passed a null HV pointer.
413 =item Badly placed ()'s
415 (A) You've accidentally run your script through B<csh> instead
416 of Perl. Check the #! line, or manually feed your script into
419 =item Bad name after %s::
421 (F) You started to name a symbol by using a package prefix, and then
422 didn't finish the symbol. In particular, you can't interpolate outside
431 $sym = "mypack::$var";
433 =item Bad plugin affecting keyword '%s'
435 (F) An extension using the keyword plugin mechanism violated the
438 =item Bad realloc() ignored
440 (S malloc) An internal routine called realloc() on something that had
441 never been malloc()ed in the first place. Mandatory, but can be disabled
442 by setting the environment variable C<PERL_BADFREE> to 1.
444 =item Bad symbol for array
446 (P) An internal request asked to add an array entry to something that
447 wasn't a symbol table entry.
449 =item Bad symbol for dirhandle
451 (P) An internal request asked to add a dirhandle entry to something
452 that wasn't a symbol table entry.
455 =item Bad symbol for filehandle
457 (P) An internal request asked to add a filehandle entry to something
458 that wasn't a symbol table entry.
460 =item Bad symbol for hash
462 (P) An internal request asked to add a hash entry to something that
463 wasn't a symbol table entry.
465 =item Bareword found in conditional
467 (W bareword) The compiler found a bareword where it expected a
468 conditional, which often indicates that an || or && was parsed as part
469 of the last argument of the previous construct, for example:
473 It may also indicate a misspelled constant that has been interpreted as
476 use constant TYPO => 1;
477 if (TYOP) { print "foo" }
479 The C<strict> pragma is useful in avoiding such errors.
481 =item Bareword "%s" not allowed while "strict subs" in use
483 (F) With "strict subs" in use, a bareword is only allowed as a
484 subroutine identifier, in curly brackets or to the left of the "=>"
485 symbol. Perhaps you need to predeclare a subroutine?
487 =item Bareword "%s" refers to nonexistent package
489 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
490 compiler saw no other uses of that namespace before that point. Perhaps
491 you need to predeclare a package?
493 =item BEGIN failed--compilation aborted
495 (F) An untrapped exception was raised while executing a BEGIN
496 subroutine. Compilation stops immediately and the interpreter is
499 =item BEGIN not safe after errors--compilation aborted
501 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
502 implies a C<BEGIN {}>) after one or more compilation errors had already
503 occurred. Since the intended environment for the C<BEGIN {}> could not
504 be guaranteed (due to the errors), and since subsequent code likely
505 depends on its correct operation, Perl just gave up.
507 =item \1 better written as $1
509 (W syntax) Outside of patterns, backreferences live on as variables.
510 The use of backslashes is grandfathered on the right-hand side of a
511 substitution, but stylistically it's better to use the variable form
512 because other Perl programmers will expect it, and it works better if
513 there are more than 9 backreferences.
515 =item Binary number > 0b11111111111111111111111111111111 non-portable
517 (W portable) The binary number you specified is larger than 2**32-1
518 (4294967295) and therefore non-portable between systems. See
519 L<perlport> for more on portability concerns.
521 =item bind() on closed socket %s
523 (W closed) You tried to do a bind on a closed socket. Did you forget to
524 check the return value of your socket() call? See L<perlfunc/bind>.
526 =item binmode() on closed filehandle %s
528 (W unopened) You tried binmode() on a filehandle that was never opened.
529 Check your control flow and number of arguments.
531 =item "\b{" is deprecated; use "\b\{" instead
533 =item "\B{" is deprecated; use "\B\{" instead
535 (W deprecated, regexp) Use of an unescaped "{" immediately following a
536 C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
537 itself in a future release.
539 =item Bit vector size > 32 non-portable
541 (W portable) Using bit vector sizes larger than 32 is non-portable.
543 =item Bizarre copy of %s in %s
545 (P) Perl detected an attempt to copy an internal value that is not
548 =item Buffer overflow in prime_env_iter: %s
550 (W internal) A warning peculiar to VMS. While Perl was preparing to
551 iterate over %ENV, it encountered a logical name or symbol definition
552 which was too long, so it was truncated to the string shown.
554 =item Callback called exit
556 (F) A subroutine invoked from an external package via call_sv()
557 exited by calling exit.
559 =item %s() called too early to check prototype
561 (W prototype) You've called a function that has a prototype before the
562 parser saw a definition or declaration for it, and Perl could not check
563 that the call conforms to the prototype. You need to either add an
564 early prototype declaration for the subroutine in question, or move the
565 subroutine definition ahead of the call to get proper prototype
566 checking. Alternatively, if you are certain that you're calling the
567 function correctly, you may put an ampersand before the name to avoid
568 the warning. See L<perlsub>.
570 =item Cannot compress integer in pack
572 (F) An argument to pack("w",...) was too large to compress. The BER
573 compressed integer format can only be used with positive integers, and you
574 attempted to compress Infinity or a very large number (> 1e308).
575 See L<perlfunc/pack>.
577 =item Cannot compress negative numbers in pack
579 (F) An argument to pack("w",...) was negative. The BER compressed integer
580 format can only be used with positive integers. See L<perlfunc/pack>.
582 =item Cannot convert a reference to %s to typeglob
584 (F) You manipulated Perl's symbol table directly, stored a reference in it,
585 then tried to access that symbol via conventional Perl syntax. The access
586 triggers Perl to autovivify that typeglob, but it there is no legal conversion
587 from that type of reference to a typeglob.
589 =item Cannot copy to %s in %s
591 (P) Perl detected an attempt to copy a value to an internal type that cannot
592 be directly assigned to.
594 =item Cannot find encoding "%s"
596 (S io) You tried to apply an encoding that did not exist to a filehandle,
597 either with open() or binmode().
599 =item Can only compress unsigned integers in pack
601 (F) An argument to pack("w",...) was not an integer. The BER compressed
602 integer format can only be used with positive integers, and you attempted
603 to compress something else. See L<perlfunc/pack>.
605 =item Can't bless non-reference value
607 (F) Only hard references may be blessed. This is how Perl "enforces"
608 encapsulation of objects. See L<perlobj>.
610 =item Can't "break" in a loop topicalizer
612 (F) You called C<break>, but you're in a C<foreach> block rather than
613 a C<given> block. You probably meant to use C<next> or C<last>.
615 =item Can't "break" outside a given block
617 (F) You called C<break>, but you're not inside a C<given> block.
619 =item Can't call method "%s" on an undefined value
621 (F) You used the syntax of a method call, but the slot filled by the
622 object reference or package name contains an undefined value. Something
623 like this will reproduce the error:
626 process $BADREF 1,2,3;
627 $BADREF->process(1,2,3);
629 =item Can't call method "%s" on unblessed reference
631 (F) A method call must know in what package it's supposed to run. It
632 ordinarily finds this out from the object reference you supply, but you
633 didn't supply an object reference in this case. A reference isn't an
634 object reference until it has been blessed. See L<perlobj>.
636 =item Can't call method "%s" without a package or object reference
638 (F) You used the syntax of a method call, but the slot filled by the
639 object reference or package name contains an expression that returns a
640 defined value which is neither an object reference nor a package name.
641 Something like this will reproduce the error:
644 process $BADREF 1,2,3;
645 $BADREF->process(1,2,3);
647 =item Can't chdir to %s
649 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
650 that you can chdir to, possibly because it doesn't exist.
652 =item Can't check filesystem of script "%s" for nosuid
654 (P) For some reason you can't check the filesystem of the script for
657 =item Can't coerce %s to %s in %s
659 (F) Certain types of SVs, in particular real symbol table entries
660 (typeglobs), can't be forced to stop being what they are. So you can't
670 but then $foo no longer contains a glob.
672 =item Can't "continue" outside a when block
674 (F) You called C<continue>, but you're not inside a C<when>
677 =item Can't create pipe mailbox
679 (P) An error peculiar to VMS. The process is suffering from exhausted
680 quotas or other plumbing problems.
682 =item Can't declare %s in "%s"
684 (F) Only scalar, array, and hash variables may be declared as "my", "our" or
685 "state" variables. They must have ordinary identifiers as names.
687 =item Can't do inplace edit: %s is not a regular file
689 (S inplace) You tried to use the B<-i> switch on a special file, such as
690 a file in /dev, or a FIFO. The file was ignored.
692 =item Can't do inplace edit on %s: %s
694 (S inplace) The creation of the new file failed for the indicated
697 =item Can't do inplace edit without backup
699 (F) You're on a system such as MS-DOS that gets confused if you try
700 reading from a deleted (but still opened) file. You have to say
701 C<-i.bak>, or some such.
703 =item Can't do inplace edit: %s would not be unique
705 (S inplace) Your filesystem does not support filenames longer than 14
706 characters and Perl was unable to create a unique filename during
707 inplace editing with the B<-i> switch. The file was ignored.
709 =item Can't do {n,m} with n > m in regex; marked by <-- HERE in m/%s/
711 (F) Minima must be less than or equal to maxima. If you really want your
712 regexp to match something 0 times, just put {0}. The <-- HERE shows in the
713 regular expression about where the problem was discovered. See L<perlre>.
715 =item Can't do waitpid with flags
717 (F) This machine doesn't have either waitpid() or wait4(), so only
718 waitpid() without flags is emulated.
720 =item Can't emulate -%s on #! line
722 (F) The #! line specifies a switch that doesn't make sense at this
723 point. For example, it'd be kind of silly to put a B<-x> on the #!
726 =item Can't %s %s-endian %ss on this platform
728 (F) Your platform's byte-order is neither big-endian nor little-endian,
729 or it has a very strange pointer size. Packing and unpacking big- or
730 little-endian floating point values and pointers may not be possible.
731 See L<perlfunc/pack>.
733 =item Can't exec "%s": %s
735 (W exec) A system(), exec(), or piped open call could not execute the
736 named program for the indicated reason. Typical reasons include: the
737 permissions were wrong on the file, the file wasn't found in
738 C<$ENV{PATH}>, the executable in question was compiled for another
739 architecture, or the #! line in a script points to an interpreter that
740 can't be run for similar reasons. (Or maybe your system doesn't support
745 (F) Perl was trying to execute the indicated program for you because
746 that's what the #! line said. If that's not what you wanted, you may
747 need to mention "perl" on the #! line somewhere.
749 =item Can't execute %s
751 (F) You used the B<-S> switch, but the copies of the script to execute
752 found in the PATH did not have correct permissions.
754 =item Can't find an opnumber for "%s"
756 (F) A string of a form C<CORE::word> was given to prototype(), but there
757 is no builtin with the name C<word>.
759 =item Can't find %s character property "%s"
761 (F) You used C<\p{}> or C<\P{}> but the character property by that name
762 could not be found. Maybe you misspelled the name of the property?
763 See L<perluniprops/Properties accessible through \p{} and \P{}>
764 for a complete list of available properties.
766 =item Can't find label %s
768 (F) You said to goto a label that isn't mentioned anywhere that it's
769 possible for us to go to. See L<perlfunc/goto>.
771 =item Can't find %s on PATH
773 (F) You used the B<-S> switch, but the script to execute could not be
776 =item Can't find %s on PATH, '.' not in PATH
778 (F) You used the B<-S> switch, but the script to execute could not be
779 found in the PATH, or at least not with the correct permissions. The
780 script exists in the current directory, but PATH prohibits running it.
782 =item Can't find string terminator %s anywhere before EOF
784 (F) Perl strings can stretch over multiple lines. This message means
785 that the closing delimiter was omitted. Because bracketed quotes count
786 nesting levels, the following is missing its final parenthesis:
788 print q(The character '(' starts a side comment.);
790 If you're getting this error from a here-document, you may have included
791 unseen whitespace before or after your closing tag. A good programmer's
792 editor will have a way to help you find these characters.
794 =item Can't find Unicode property definition "%s"
796 (F) You may have tried to use C<\p> which means a Unicode
797 property (for example C<\p{Lu}> matches all uppercase
798 letters). If you did mean to use a Unicode property, see
799 L<perluniprops/Properties accessible through \p{} and \P{}>
800 for a complete list of available properties. If you didn't
801 mean to use a Unicode property, escape the C<\p>, either by C<\\p>
802 (just the C<\p>) or by C<\Q\p> (the rest of the string, or
807 (F) A fatal error occurred while trying to fork while opening a
810 =item Can't fork, trying again in 5 seconds
812 (W pipe) A fork in a piped open failed with EAGAIN and will be retried
815 =item Can't get filespec - stale stat buffer?
817 (S) A warning peculiar to VMS. This arises because of the difference
818 between access checks under VMS and under the Unix model Perl assumes.
819 Under VMS, access checks are done by filename, rather than by bits in
820 the stat buffer, so that ACLs and other protections can be taken into
821 account. Unfortunately, Perl assumes that the stat buffer contains all
822 the necessary information, and passes it, instead of the filespec, to
823 the access-checking routine. It will try to retrieve the filespec using
824 the device name and FID present in the stat buffer, but this works only
825 if you haven't made a subsequent call to the CRTL stat() routine,
826 because the device name is overwritten with each call. If this warning
827 appears, the name lookup failed, and the access-checking routine gave up
828 and returned FALSE, just to be conservative. (Note: The access-checking
829 routine knows about the Perl C<stat> operator and file tests, so you
830 shouldn't ever see this warning in response to a Perl command; it arises
831 only if some internal code takes stat buffers lightly.)
833 =item Can't get pipe mailbox device name
835 (P) An error peculiar to VMS. After creating a mailbox to act as a
836 pipe, Perl can't retrieve its name for later use.
838 =item Can't get SYSGEN parameter value for MAXBUF
840 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
841 mailbox buffers to be, and didn't get an answer.
843 =item Can't "goto" into the middle of a foreach loop
845 (F) A "goto" statement was executed to jump into the middle of a foreach
846 loop. You can't get there from here. See L<perlfunc/goto>.
848 =item Can't "goto" out of a pseudo block
850 (F) A "goto" statement was executed to jump out of what might look like
851 a block, except that it isn't a proper block. This usually occurs if
852 you tried to jump out of a sort() block or subroutine, which is a no-no.
853 See L<perlfunc/goto>.
855 =item Can't goto subroutine from a sort sub (or similar callback)
857 (F) The "goto subroutine" call can't be used to jump out of the
858 comparison sub for a sort(), or from a similar callback (such
859 as the reduce() function in List::Util).
861 =item Can't goto subroutine from an eval-%s
863 (F) The "goto subroutine" call can't be used to jump out of an eval
866 =item Can't goto subroutine outside a subroutine
868 (F) The deeply magical "goto subroutine" call can only replace one
869 subroutine call for another. It can't manufacture one out of whole
870 cloth. In general you should be calling it out of only an AUTOLOAD
871 routine anyway. See L<perlfunc/goto>.
873 =item Can't ignore signal CHLD, forcing to default
875 (W signal) Perl has detected that it is being run with the SIGCHLD
876 signal (sometimes known as SIGCLD) disabled. Since disabling this
877 signal will interfere with proper determination of exit status of child
878 processes, Perl has reset the signal to its default value. This
879 situation typically indicates that the parent program under which Perl
880 may be running (e.g. cron) is being very careless.
882 =item Can't kill a non-numeric process ID
884 (F) Process identifiers must be (signed) integers. It is a fatal error to
885 attempt to kill() an undefined, empty-string or otherwise non-numeric
888 =item Can't "last" outside a loop block
890 (F) A "last" statement was executed to break out of the current block,
891 except that there's this itty bitty problem called there isn't a current
892 block. Note that an "if" or "else" block doesn't count as a "loopish"
893 block, as doesn't a block given to sort(), map() or grep(). You can
894 usually double the curlies to get the same effect though, because the
895 inner curlies will be considered a block that loops once. See
898 =item Can't linearize anonymous symbol table
900 (F) Perl tried to calculate the method resolution order (MRO) of a
901 package, but failed because the package stash has no name.
903 =item Can't load '%s' for module %s
905 (F) The module you tried to load failed to load a dynamic extension. This
906 may either mean that you upgraded your version of perl to one that is
907 incompatible with your old dynamic extensions (which is known to happen
908 between major versions of perl), or (more likely) that your dynamic
909 extension was built against an older version of the library that is
910 installed on your system. You may need to rebuild your old dynamic
913 =item Can't localize lexical variable %s
915 (F) You used local on a variable name that was previously declared as a
916 lexical variable using "my" or "state". This is not allowed. If you want to
917 localize a package variable of the same name, qualify it with the
920 =item Can't localize through a reference
922 (F) You said something like C<local $$ref>, which Perl can't currently
923 handle, because when it goes to restore the old value of whatever $ref
924 pointed to after the scope of the local() is finished, it can't be sure
925 that $ref will still be a reference.
927 =item Can't locate %s
929 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be
930 found. Perl looks for the file in all the locations mentioned in @INC,
931 unless the file name included the full path to the file. Perhaps you
932 need to set the PERL5LIB or PERL5OPT environment variable to say where
933 the extra library is, or maybe the script needs to add the library name
934 to @INC. Or maybe you just misspelled the name of the file. See
935 L<perlfunc/require> and L<lib>.
937 =item Can't locate auto/%s.al in @INC
939 (F) A function (or method) was called in a package which allows
940 autoload, but there is no function to autoload. Most probable causes
941 are a misprint in a function/method name or a failure to C<AutoSplit>
942 the file, say, by doing C<make install>.
944 =item Can't locate loadable object for module %s in @INC
946 (F) The module you loaded is trying to load an external library, like
947 for example, C<foo.so> or C<bar.dll>, but the L<DynaLoader> module was
948 unable to locate this library. See L<DynaLoader>.
950 =item Can't locate object method "%s" via package "%s"
952 (F) You called a method correctly, and it correctly indicated a package
953 functioning as a class, but that package doesn't define that particular
954 method, nor does any of its base classes. See L<perlobj>.
956 =item Can't locate package %s for @%s::ISA
958 (W syntax) The @ISA array contained the name of another package that
959 doesn't seem to exist.
961 =item Can't locate PerlIO%s
963 (F) You tried to use in open() a PerlIO layer that does not exist,
964 e.g. open(FH, ">:nosuchlayer", "somefile").
966 =item Can't make list assignment to \%ENV on this system
968 (F) List assignment to %ENV is not supported on some systems, notably
971 =item Can't modify %s in %s
973 (F) You aren't allowed to assign to the item indicated, or otherwise try
974 to change it, such as with an auto-increment.
976 =item Can't modify nonexistent substring
978 (P) The internal routine that does assignment to a substr() was handed
981 =item Can't modify non-lvalue subroutine call
983 (F) Subroutines meant to be used in lvalue context should be declared as
984 such. See L<perlsub/"Lvalue subroutines">.
986 =item Can't msgrcv to read-only var
988 (F) The target of a msgrcv must be modifiable to be used as a receive
991 =item Can't "next" outside a loop block
993 (F) A "next" statement was executed to reiterate the current block, but
994 there isn't a current block. Note that an "if" or "else" block doesn't
995 count as a "loopish" block, as doesn't a block given to sort(), map() or
996 grep(). You can usually double the curlies to get the same effect
997 though, because the inner curlies will be considered a block that loops
998 once. See L<perlfunc/next>.
1000 =item Can't open %s: %s
1002 (S inplace) The implicit opening of a file through use of the C<< <> >>
1003 filehandle, either implicitly under the C<-n> or C<-p> command-line
1004 switches, or explicitly, failed for the indicated reason. Usually this
1005 is because you don't have read permission for a file which you named on
1008 =item Can't open a reference
1010 (W io) You tried to open a scalar reference for reading or writing,
1011 using the 3-arg open() syntax:
1015 but your version of perl is compiled without perlio, and this form of
1016 open is not supported.
1018 =item Can't open bidirectional pipe
1020 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1021 You can try any of several modules in the Perl library to do this, such
1022 as IPC::Open2. Alternately, direct the pipe's output to a file using
1023 ">", and then read it in under a different file handle.
1025 =item Can't open error file %s as stderr
1027 (F) An error peculiar to VMS. Perl does its own command line
1028 redirection, and couldn't open the file specified after '2>' or '2>>' on
1029 the command line for writing.
1031 =item Can't open input file %s as stdin
1033 (F) An error peculiar to VMS. Perl does its own command line
1034 redirection, and couldn't open the file specified after '<' on the
1035 command line for reading.
1037 =item Can't open output file %s as stdout
1039 (F) An error peculiar to VMS. Perl does its own command line
1040 redirection, and couldn't open the file specified after '>' or '>>' on
1041 the command line for writing.
1043 =item Can't open output pipe (name: %s)
1045 (P) An error peculiar to VMS. Perl does its own command line
1046 redirection, and couldn't open the pipe into which to send data destined
1049 =item Can't open perl script%s
1051 (F) The script you specified can't be opened for the indicated reason.
1053 If you're debugging a script that uses #!, and normally relies on the
1054 shell's $PATH search, the -S option causes perl to do that search, so
1055 you don't have to type the path or C<`which $scriptname`>.
1057 =item Can't read CRTL environ
1059 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1060 from the CRTL's internal environment array and discovered the array was
1061 missing. You need to figure out where your CRTL misplaced its environ
1062 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1065 =item Can't "redo" outside a loop block
1067 (F) A "redo" statement was executed to restart the current block, but
1068 there isn't a current block. Note that an "if" or "else" block doesn't
1069 count as a "loopish" block, as doesn't a block given to sort(), map()
1070 or grep(). You can usually double the curlies to get the same effect
1071 though, because the inner curlies will be considered a block that
1072 loops once. See L<perlfunc/redo>.
1074 =item Can't remove %s: %s, skipping file
1076 (S inplace) You requested an inplace edit without creating a backup
1077 file. Perl was unable to remove the original file to replace it with
1078 the modified file. The file was left unmodified.
1080 =item Can't rename %s to %s: %s, skipping file
1082 (S inplace) The rename done by the B<-i> switch failed for some reason,
1083 probably because you don't have write permission to the directory.
1085 =item Can't reopen input pipe (name: %s) in binary mode
1087 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1088 to reopen it to accept binary data. Alas, it failed.
1090 =item Can't resolve method "%s" overloading "%s" in package "%s"
1092 (F|P) Error resolving overloading specified by a method name (as opposed
1093 to a subroutine reference): no such method callable via the package. If
1094 the method name is C<???>, this is an internal error.
1096 =item Can't return %s from lvalue subroutine
1098 (F) Perl detected an attempt to return illegal lvalues (such as
1099 temporary or readonly values) from a subroutine used as an lvalue. This
1102 =item Can't return outside a subroutine
1104 (F) The return statement was executed in mainline code, that is, where
1105 there was no subroutine call to return out of. See L<perlsub>.
1107 =item Can't return %s to lvalue scalar context
1109 (F) You tried to return a complete array or hash from an lvalue subroutine,
1110 but you called the subroutine in a way that made Perl think you meant
1111 to return only one value. You probably meant to write parentheses around
1112 the call to the subroutine, which tell Perl that the call should be in
1115 =item Can't stat script "%s"
1117 (P) For some reason you can't fstat() the script even though you have it
1118 open already. Bizarre.
1120 =item Can't take log of %g
1122 (F) For ordinary real numbers, you can't take the logarithm of a
1123 negative number or zero. There's a Math::Complex package that comes
1124 standard with Perl, though, if you really want to do that for the
1127 =item Can't take sqrt of %g
1129 (F) For ordinary real numbers, you can't take the square root of a
1130 negative number. There's a Math::Complex package that comes standard
1131 with Perl, though, if you really want to do that.
1133 =item Can't undef active subroutine
1135 (F) You can't undefine a routine that's currently running. You can,
1136 however, redefine it while it's running, and you can even undef the
1137 redefined subroutine while the old routine is running. Go figure.
1139 =item Can't upgrade %s (%d) to %d
1141 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1142 into a more specialized kind of SV. The top several SV types are so
1143 specialized, however, that they cannot be interconverted. This message
1144 indicates that such a conversion was attempted.
1146 =item Can't use anonymous symbol table for method lookup
1148 (F) The internal routine that does method lookup was handed a symbol
1149 table that doesn't have a name. Symbol tables can become anonymous
1150 for example by undefining stashes: C<undef %Some::Package::>.
1152 =item Can't use an undefined value as %s reference
1154 (F) A value used as either a hard reference or a symbolic reference must
1155 be a defined value. This helps to delurk some insidious errors.
1157 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1159 (F) Only hard references are allowed by "strict refs". Symbolic
1160 references are disallowed. See L<perlref>.
1162 =item Can't use %! because Errno.pm is not available
1164 (F) The first time the %! hash is used, perl automatically loads the
1165 Errno.pm module. The Errno module is expected to tie the %! hash to
1166 provide symbolic names for C<$!> errno values.
1168 =item Can't use both '<' and '>' after type '%c' in %s
1170 (F) A type cannot be forced to have both big-endian and little-endian
1171 byte-order at the same time, so this combination of modifiers is not
1172 allowed. See L<perlfunc/pack>.
1174 =item Can't use %s for loop variable
1176 (F) Only a simple scalar variable may be used as a loop variable on a
1179 =item Can't use global %s in "%s"
1181 (F) You tried to declare a magical variable as a lexical variable. This
1182 is not allowed, because the magic can be tied to only one location
1183 (namely the global variable) and it would be incredibly confusing to
1184 have variables in your program that looked like magical variables but
1187 =item Can't use '%c' in a group with different byte-order in %s
1189 (F) You attempted to force a different byte-order on a type
1190 that is already inside a group with a byte-order modifier.
1191 For example you cannot force little-endianness on a type that
1192 is inside a big-endian group.
1194 =item Can't use "my %s" in sort comparison
1196 (F) The global variables $a and $b are reserved for sort comparisons.
1197 You mentioned $a or $b in the same line as the <=> or cmp operator,
1198 and the variable had earlier been declared as a lexical variable.
1199 Either qualify the sort variable with the package name, or rename the
1202 =item Can't use %s ref as %s ref
1204 (F) You've mixed up your reference types. You have to dereference a
1205 reference of the type needed. You can use the ref() function to
1206 test the type of the reference, if need be.
1208 =item Can't use string ("%s") as %s ref while "strict refs" in use
1210 (F) Only hard references are allowed by "strict refs". Symbolic
1211 references are disallowed. See L<perlref>.
1213 =item Can't use subscript on %s
1215 (F) The compiler tried to interpret a bracketed expression as a
1216 subscript. But to the left of the brackets was an expression that
1217 didn't look like a hash or array reference, or anything else subscriptable.
1219 =item Can't use \%c to mean $%c in expression
1221 (W syntax) In an ordinary expression, backslash is a unary operator that
1222 creates a reference to its argument. The use of backslash to indicate a
1223 backreference to a matched substring is valid only as part of a regular
1224 expression pattern. Trying to do this in ordinary Perl code produces a
1225 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1228 =item Can't use "when" outside a topicalizer
1230 (F) You have used a when() block that is neither inside a C<foreach>
1231 loop nor a C<given> block. (Note that this error is issued on exit
1232 from the C<when> block, so you won't get the error if the match fails,
1233 or if you use an explicit C<continue>.)
1235 =item Can't weaken a nonreference
1237 (F) You attempted to weaken something that was not a reference. Only
1238 references can be weakened.
1240 =item Can't x= to read-only value
1242 (F) You tried to repeat a constant value (often the undefined value)
1243 with an assignment operator, which implies modifying the value itself.
1244 Perhaps you need to copy the value to a temporary, and repeat that.
1246 =item Character following "\c" must be ASCII
1248 (F|W deprecated, syntax) In C<\cI<X>>, I<X> must be an ASCII character.
1249 It is planned to make this fatal in all instances in Perl 5.16. In the
1250 cases where it isn't fatal, the character this evaluates to is
1251 derived by exclusive or'ing the code point of this character with 0x40.
1253 Note that non-alphabetic ASCII characters are discouraged here as well.
1255 =item Character in 'C' format wrapped in pack
1261 where $x is either less than 0 or more than 255; the C<"C"> format is
1262 only for encoding native operating system characters (ASCII, EBCDIC,
1263 and so on) and not for Unicode characters, so Perl behaved as if you meant
1267 If you actually want to pack Unicode codepoints, use the C<"U"> format
1270 =item Character in 'W' format wrapped in pack
1276 where $x is either less than 0 or more than 255. However, C<U0>-mode expects
1277 all values to fall in the interval [0, 255], so Perl behaved as if you
1280 pack("U0W", $x & 255)
1282 =item Character in 'c' format wrapped in pack
1288 where $x is either less than -128 or more than 127; the C<"c"> format
1289 is only for encoding native operating system characters (ASCII, EBCDIC,
1290 and so on) and not for Unicode characters, so Perl behaved as if you meant
1292 pack("c", $x & 255);
1294 If you actually want to pack Unicode codepoints, use the C<"U"> format
1297 =item Character in '%c' format wrapped in unpack
1299 (W unpack) You tried something like
1301 unpack("H", "\x{2a1}")
1303 where the format expects to process a byte (a character with a value
1304 below 256), but a higher value was provided instead. Perl uses the value
1305 modulus 256 instead, as if you had provided:
1307 unpack("H", "\x{a1}")
1309 =item Character(s) in '%c' format wrapped in pack
1311 (W pack) You tried something like
1313 pack("u", "\x{1f3}b")
1315 where the format expects to process a sequence of bytes (character with a
1316 value below 256), but some of the characters had a higher value. Perl
1317 uses the character values modulus 256 instead, as if you had provided:
1319 pack("u", "\x{f3}b")
1321 =item Character(s) in '%c' format wrapped in unpack
1323 (W unpack) You tried something like
1325 unpack("s", "\x{1f3}b")
1327 where the format expects to process a sequence of bytes (character with a
1328 value below 256), but some of the characters had a higher value. Perl
1329 uses the character values modulus 256 instead, as if you had provided:
1331 unpack("s", "\x{f3}b")
1333 =item "\c{" is deprecated and is more clearly written as ";"
1335 (D deprecated, syntax) The C<\cI<X>> construct is intended to be a way
1336 to specify non-printable characters. You used it with a "{" which
1337 evaluates to ";", which is printable. It is planned to remove the
1338 ability to specify a semi-colon this way in Perl 5.16. Just use a
1339 semi-colon or a backslash-semi-colon without the "\c".
1341 =item "\c%c" is more clearly written simply as "%s"
1343 (W syntax) The C<\cI<X>> construct is intended to be a way to specify
1344 non-printable characters. You used it for a printable one, which is better
1345 written as simply itself, perhaps preceded by a backslash for non-word
1348 =item close() on unopened filehandle %s
1350 (W unopened) You tried to close a filehandle that was never opened.
1352 =item closedir() attempted on invalid dirhandle %s
1354 (W io) The dirhandle you tried to close is either closed or not really
1355 a dirhandle. Check your control flow.
1357 =item Closure prototype called
1359 (F) If a closure has attributes, the subroutine passed to an attribute
1360 handler is the prototype that is cloned when a new closure is created.
1361 This subroutine cannot be called.
1363 =item Code missing after '/'
1365 (F) You had a (sub-)template that ends with a '/'. There must be another
1366 template code following the slash. See L<perlfunc/pack>.
1368 =item Code point 0x%X is not Unicode, may not be portable
1370 =item Code point 0x%X is not Unicode, no properties match it; all inverse properties do
1372 (W utf8) You had a code point above the Unicode maximum of U+10FFFF.
1374 Perl allows strings to contain a superset of Unicode code
1375 points, up to the limit of what is storable in an unsigned integer on
1376 your system, but these may not be accepted by other languages/systems.
1377 At one time, it was legal in some standards to have code points up to
1378 0x7FFF_FFFF, but not higher. Code points above 0xFFFF_FFFF require
1379 larger than a 32 bit word.
1381 None of the Unicode or Perl-defined properties will match a non-Unicode
1382 code point. For example,
1384 chr(0x7FF_FFFF) =~ /\p{Any}/
1386 will not match, because the code point is not in Unicode. But
1388 chr(0x7FF_FFFF) =~ /\P{Any}/
1392 =item %s: Command not found
1394 (A) You've accidentally run your script through B<csh> instead of Perl.
1395 Check the #! line, or manually feed your script into Perl yourself.
1397 =item Compilation failed in require
1399 (F) Perl could not compile a file specified in a C<require> statement.
1400 Perl uses this generic message when none of the errors that it
1401 encountered were severe enough to halt compilation immediately.
1403 =item Complex regular subexpression recursion limit (%d) exceeded
1405 (W regexp) The regular expression engine uses recursion in complex
1406 situations where back-tracking is required. Recursion depth is limited
1407 to 32766, or perhaps less in architectures where the stack cannot grow
1408 arbitrarily. ("Simple" and "medium" situations are handled without
1409 recursion and are not subject to a limit.) Try shortening the string
1410 under examination; looping in Perl code (e.g. with C<while>) rather than
1411 in the regular expression engine; or rewriting the regular expression so
1412 that it is simpler or backtracks less. (See L<perlfaq2> for information
1413 on I<Mastering Regular Expressions>.)
1415 =item cond_broadcast() called on unlocked variable
1417 (W threads) Within a thread-enabled program, you tried to call
1418 cond_broadcast() on a variable which wasn't locked. The cond_broadcast()
1419 function is used to wake up another thread that is waiting in a
1420 cond_wait(). To ensure that the signal isn't sent before the other thread
1421 has a chance to enter the wait, it is usual for the signaling thread
1422 first to wait for a lock on variable. This lock attempt will only succeed
1423 after the other thread has entered cond_wait() and thus relinquished the
1426 =item cond_signal() called on unlocked variable
1428 (W threads) Within a thread-enabled program, you tried to call
1429 cond_signal() on a variable which wasn't locked. The cond_signal()
1430 function is used to wake up another thread that is waiting in a
1431 cond_wait(). To ensure that the signal isn't sent before the other thread
1432 has a chance to enter the wait, it is usual for the signaling thread
1433 first to wait for a lock on variable. This lock attempt will only succeed
1434 after the other thread has entered cond_wait() and thus relinquished the
1437 =item connect() on closed socket %s
1439 (W closed) You tried to do a connect on a closed socket. Did you forget
1440 to check the return value of your socket() call? See
1441 L<perlfunc/connect>.
1443 =item Constant(%s)%s: %s
1445 (F) The parser found inconsistencies either while attempting to define
1446 an overloaded constant, or when trying to find the character name
1447 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1448 corresponding C<overload> or C<charnames> pragma? See L<charnames> and
1451 =item Constant(%s)%s: %s in regex; marked by <-- HERE in m/%s/
1453 (F) The parser found inconsistencies while attempting to find
1454 the character name specified in the C<\N{...}> escape. Perhaps you
1455 forgot to load the corresponding C<charnames> pragma?
1459 =item Constant is not %s reference
1461 (F) A constant value (perhaps declared using the C<use constant> pragma)
1462 is being dereferenced, but it amounts to the wrong type of reference.
1463 The message indicates the type of reference that was expected. This
1464 usually indicates a syntax error in dereferencing the constant value.
1465 See L<perlsub/"Constant Functions"> and L<constant>.
1467 =item Constant subroutine %s redefined
1469 (S) You redefined a subroutine which had previously been
1470 eligible for inlining. See L<perlsub/"Constant Functions"> for
1471 commentary and workarounds.
1473 =item Constant subroutine %s undefined
1475 (W misc) You undefined a subroutine which had previously been eligible
1476 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1479 =item Copy method did not return a reference
1481 (F) The method which overloads "=" is buggy. See
1482 L<overload/Copy Constructor>.
1484 =item CORE::%s is not a keyword
1486 (F) The CORE:: namespace is reserved for Perl keywords.
1488 =item corrupted regexp pointers
1490 (P) The regular expression engine got confused by what the regular
1491 expression compiler gave it.
1493 =item corrupted regexp program
1495 (P) The regular expression engine got passed a regexp program without a
1498 =item Corrupt malloc ptr 0x%x at 0x%x
1500 (P) The malloc package that comes with Perl had an internal failure.
1502 =item Count after length/code in unpack
1504 (F) You had an unpack template indicating a counted-length string, but
1505 you have also specified an explicit size for the string. See
1508 =item Deep recursion on subroutine "%s"
1510 (W recursion) This subroutine has called itself (directly or indirectly)
1511 100 times more than it has returned. This probably indicates an
1512 infinite recursion, unless you're writing strange benchmark programs, in
1513 which case it indicates something else.
1515 This threshold can be changed from 100, by recompiling the F<perl> binary,
1516 setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1518 =item defined(@array) is deprecated
1520 (D deprecated) defined() is not usually useful on arrays because it
1521 checks for an undefined I<scalar> value. If you want to see if the
1522 array is empty, just use C<if (@array) { # not empty }> for example.
1524 =item defined(%hash) is deprecated
1526 (D deprecated) defined() is not usually useful on hashes because it
1527 checks for an undefined I<scalar> value. If you want to see if the hash
1528 is empty, just use C<if (%hash) { # not empty }> for example.
1530 =item (?(DEFINE)....) does not allow branches in regex; marked by <-- HERE in m/%s/
1532 (F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
1533 most likely cause of this error is that you left out a parenthesis inside
1534 of the C<....> part.
1536 The <-- HERE shows in the regular expression about where the problem was
1539 =item %s defines neither package nor VERSION--version check failed
1541 (F) You said something like "use Module 42" but in the Module file
1542 there are neither package declarations nor a C<$VERSION>.
1544 =item Delimiter for here document is too long
1546 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1547 long for Perl to handle. You have to be seriously twisted to write code
1548 that triggers this error.
1550 =item Deprecated character in \N{...}; marked by <-- HERE in \N{%s<-- HERE %s
1552 (D deprecated) Just about anything is legal for the C<...> in C<\N{...}>.
1553 But starting in 5.12, non-reasonable ones that don't look like names
1554 are deprecated. A reasonable name begins with an alphabetic character
1555 and continues with any combination of alphanumerics, dashes, spaces,
1556 parentheses or colons.
1558 =item Deprecated use of my() in false conditional
1560 (D deprecated) You used a declaration similar to C<my $x if 0>.
1561 There has been a long-standing bug in Perl that causes a lexical variable
1562 not to be cleared at scope exit when its declaration includes a false
1563 conditional. Some people have exploited this bug to achieve a kind of
1564 static variable. Since we intend to fix this bug, we don't want people
1565 relying on this behavior. You can achieve a similar static effect by
1566 declaring the variable in a separate block outside the function, eg
1568 sub f { my $x if 0; return $x++ }
1572 { my $x; sub f { return $x++ } }
1574 Beginning with perl 5.9.4, you can also use C<state> variables to
1575 have lexicals that are initialized only once (see L<feature>):
1577 sub f { state $x; return $x++ }
1579 =item DESTROY created new reference to dead object '%s'
1581 (F) A DESTROY() method created a new reference to the object which is
1582 just being DESTROYed. Perl is confused, and prefers to abort rather than
1583 to create a dangling reference.
1585 =item Did not produce a valid header
1589 =item %s did not return a true value
1591 (F) A required (or used) file must return a true value to indicate that
1592 it compiled correctly and ran its initialization code correctly. It's
1593 traditional to end such a file with a "1;", though any true value would
1594 do. See L<perlfunc/require>.
1596 =item (Did you mean &%s instead?)
1598 (W misc) You probably referred to an imported subroutine &FOO as $FOO or
1601 =item (Did you mean "local" instead of "our"?)
1603 (W misc) Remember that "our" does not localize the declared global
1604 variable. You have declared it again in the same lexical scope, which
1607 =item (Did you mean $ or @ instead of %?)
1609 (W) You probably said %hash{$key} when you meant $hash{$key} or
1610 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1615 (F) You passed die() an empty string (the equivalent of C<die "">) or
1616 you called it with no args and C<$@> was empty.
1618 =item Document contains no data
1622 =item %s does not define %s::VERSION--version check failed
1624 (F) You said something like "use Module 42" but the Module did not
1625 define a C<$VERSION.>
1627 =item '/' does not take a repeat count
1629 (F) You cannot put a repeat count of any kind right after the '/' code.
1630 See L<perlfunc/pack>.
1632 =item Don't know how to handle magic of type '%s'
1634 (P) The internal handling of magical variables has been cursed.
1636 =item do_study: out of memory
1638 (P) This should have been caught by safemalloc() instead.
1640 =item (Do you need to predeclare %s?)
1642 (S syntax) This is an educated guess made in conjunction with the message
1643 "%s found where operator expected". It often means a subroutine or module
1644 name is being referenced that hasn't been declared yet. This may be
1645 because of ordering problems in your file, or because of a missing
1646 "sub", "package", "require", or "use" statement. If you're referencing
1647 something that isn't defined yet, you don't actually have to define the
1648 subroutine or package before the current location. You can use an empty
1649 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1651 =item dump() better written as CORE::dump()
1653 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1654 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1656 =item dump is not supported
1658 (F) Your machine doesn't support dump/undump.
1660 =item Duplicate free() ignored
1662 (S malloc) An internal routine called free() on something that had
1665 =item Duplicate modifier '%c' after '%c' in %s
1667 (W) You have applied the same modifier more than once after a type
1668 in a pack template. See L<perlfunc/pack>.
1670 =item elseif should be elsif
1672 (S syntax) There is no keyword "elseif" in Perl because Larry thinks it's
1673 ugly. Your code will be interpreted as an attempt to call a method named
1674 "elseif" for the class returned by the following block. This is
1675 unlikely to be what you want.
1679 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1680 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1681 a regular expression without specifying the property name.
1683 =item entering effective %s failed
1685 (F) While under the C<use filetest> pragma, switching the real and
1686 effective uids or gids failed.
1688 =item %ENV is aliased to %s
1690 (F) You're running under taint mode, and the C<%ENV> variable has been
1691 aliased to another hash, so it doesn't reflect anymore the state of the
1692 program's environment. This is potentially insecure.
1694 =item Error converting file specification %s
1696 (F) An error peculiar to VMS. Because Perl may have to deal with file
1697 specifications in either VMS or Unix syntax, it converts them to a
1698 single form when it must operate on them directly. Either you've passed
1699 an invalid file specification to Perl, or you've found a case the
1700 conversion routines don't handle. Drat.
1702 =item %s: Eval-group in insecure regular expression
1704 (F) Perl detected tainted data when trying to compile a regular
1705 expression that contains the C<(?{ ... })> zero-width assertion, which
1706 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1708 =item %s: Eval-group not allowed at runtime, use re 'eval'
1710 (F) Perl tried to compile a regular expression containing the
1711 C<(?{ ... })> zero-width assertion at run time, as it would when the
1712 pattern contains interpolated values. Since that is a security risk,
1713 it is not allowed. If you insist, you may still do this by using the
1714 C<re 'eval'> pragma or by explicitly building the pattern from an
1715 interpolated string at run time and using that in an eval(). See
1716 L<perlre/(?{ code })>.
1718 =item %s: Eval-group not allowed, use re 'eval'
1720 (F) A regular expression contained the C<(?{ ... })> zero-width
1721 assertion, but that construct is only allowed when the C<use re 'eval'>
1722 pragma is in effect. See L<perlre/(?{ code })>.
1724 =item EVAL without pos change exceeded limit in regex; marked by <-- HERE in m/%s/
1726 (F) You used a pattern that nested too many EVAL calls without consuming
1727 any text. Restructure the pattern so that text is consumed.
1729 The <-- HERE shows in the regular expression about where the problem was
1732 =item Excessively long <> operator
1734 (F) The contents of a <> operator may not exceed the maximum size of a
1735 Perl identifier. If you're just trying to glob a long list of
1736 filenames, try using the glob() operator, or put the filenames into a
1737 variable and glob that.
1739 =item exec? I'm not *that* kind of operating system
1741 (F) The C<exec> function is not implemented on some systems, e.g., Symbian
1742 OS. See L<perlport>.
1744 =item Execution of %s aborted due to compilation errors.
1746 (F) The final summary message when a Perl compilation fails.
1748 =item Exiting eval via %s
1750 (W exiting) You are exiting an eval by unconventional means, such as a
1751 goto, or a loop control statement.
1753 =item Exiting format via %s
1755 (W exiting) You are exiting a format by unconventional means, such as a
1756 goto, or a loop control statement.
1758 =item Exiting pseudo-block via %s
1760 (W exiting) You are exiting a rather special block construct (like a
1761 sort block or subroutine) by unconventional means, such as a goto, or a
1762 loop control statement. See L<perlfunc/sort>.
1764 =item Exiting subroutine via %s
1766 (W exiting) You are exiting a subroutine by unconventional means, such
1767 as a goto, or a loop control statement.
1769 =item Exiting substitution via %s
1771 (W exiting) You are exiting a substitution by unconventional means, such
1772 as a return, a goto, or a loop control statement.
1774 =item Explicit blessing to '' (assuming package main)
1776 (W misc) You are blessing a reference to a zero length string. This has
1777 the effect of blessing the reference into the package main. This is
1778 usually not what you want. Consider providing a default target package,
1779 e.g. bless($ref, $p || 'MyPackage');
1781 =item %s: Expression syntax
1783 (A) You've accidentally run your script through B<csh> instead of Perl.
1784 Check the #! line, or manually feed your script into Perl yourself.
1786 =item %s failed--call queue aborted
1788 (F) An untrapped exception was raised while executing a UNITCHECK,
1789 CHECK, INIT, or END subroutine. Processing of the remainder of the
1790 queue of such routines has been prematurely ended.
1792 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1794 (W regexp) A character class range must start and end at a literal
1795 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1796 in your false range is interpreted as a literal "-". Consider quoting the
1797 "-", "\-". The <-- HERE shows in the regular expression about where the
1798 problem was discovered. See L<perlre>.
1800 =item Fatal VMS error (status=%d) at %s, line %d
1802 (P) An error peculiar to VMS. Something untoward happened in a VMS
1803 system service or RTL routine; Perl's exit status should provide more
1804 details. The filename in "at %s" and the line number in "line %d" tell
1805 you which section of the Perl source code is distressed.
1807 =item fcntl is not implemented
1809 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1810 PDP-11 or something?
1812 =item FETCHSIZE returned a negative value
1814 (F) A tied array claimed to have a negative number of elements, which
1817 =item Field too wide in 'u' format in pack
1819 (W pack) Each line in an uuencoded string start with a length indicator
1820 which can't encode values above 63. So there is no point in asking for
1821 a line length bigger than that. Perl will behave as if you specified
1822 C<u63> as the format.
1824 =item Filehandle %s opened only for input
1826 (W io) You tried to write on a read-only filehandle. If you intended
1827 it to be a read-write filehandle, you needed to open it with "+<" or
1828 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1829 write the file, use ">" or ">>". See L<perlfunc/open>.
1831 =item Filehandle %s opened only for output
1833 (W io) You tried to read from a filehandle opened only for writing, If
1834 you intended it to be a read/write filehandle, you needed to open it
1835 with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1836 read from the file, use "<". See L<perlfunc/open>. Another possibility
1837 is that you attempted to open filedescriptor 0 (also known as STDIN) for
1838 output (maybe you closed STDIN earlier?).
1840 =item Filehandle %s reopened as %s only for input
1842 (W io) You opened for reading a filehandle that got the same filehandle id
1843 as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
1846 =item Filehandle STDIN reopened as %s only for output
1848 (W io) You opened for writing a filehandle that got the same filehandle id
1849 as STDIN. This occurred because you closed STDIN previously.
1851 =item Final $ should be \$ or $name
1853 (F) You must now decide whether the final $ in a string was meant to be
1854 a literal dollar sign, or was meant to introduce a variable name that
1855 happens to be missing. So you have to put either the backslash or the
1858 =item flock() on closed filehandle %s
1860 (W closed) The filehandle you're attempting to flock() got itself closed
1861 some time before now. Check your control flow. flock() operates on
1862 filehandles. Are you attempting to call flock() on a dirhandle by the
1865 =item Format not terminated
1867 (F) A format must be terminated by a line with a solitary dot. Perl got
1868 to the end of your file without finding such a line.
1870 =item Format %s redefined
1872 (W redefine) You redefined a format. To suppress this warning, say
1875 no warnings 'redefine';
1876 eval "format NAME =...";
1879 =item Found = in conditional, should be ==
1889 (or something like that).
1891 =item %s found where operator expected
1893 (S syntax) The Perl lexer knows whether to expect a term or an operator.
1894 If it sees what it knows to be a term when it was expecting to see an
1895 operator, it gives you this warning. Usually it indicates that an
1896 operator or delimiter was omitted, such as a semicolon.
1898 =item gdbm store returned %d, errno %d, key "%s"
1900 (S) A warning from the GDBM_File extension that a store failed.
1902 =item gethostent not implemented
1904 (F) Your C library apparently doesn't implement gethostent(), probably
1905 because if it did, it'd feel morally obligated to return every hostname
1908 =item get%sname() on closed socket %s
1910 (W closed) You tried to get a socket or peer socket name on a closed
1911 socket. Did you forget to check the return value of your socket() call?
1913 =item getpwnam returned invalid UIC %#o for user "%s"
1915 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1916 C<getpwnam> operator returned an invalid UIC.
1918 =item getsockopt() on closed socket %s
1920 (W closed) You tried to get a socket option on a closed socket. Did you
1921 forget to check the return value of your socket() call? See
1922 L<perlfunc/getsockopt>.
1924 =item Global symbol "%s" requires explicit package name
1926 (F) You've said "use strict" or "use strict vars", which indicates
1927 that all variables must either be lexically scoped (using "my" or "state"),
1928 declared beforehand using "our", or explicitly qualified to say
1929 which package the global variable is in (using "::").
1931 =item glob failed (%s)
1933 (W glob) Something went wrong with the external program(s) used for
1934 C<glob> and C<< <*.c> >>. Usually, this means that you supplied a
1935 C<glob> pattern that caused the external program to fail and exit with a
1936 nonzero status. If the message indicates that the abnormal exit
1937 resulted in a coredump, this may also mean that your csh (C shell) is
1938 broken. If so, you should change all of the csh-related variables in
1939 config.sh: If you have tcsh, make the variables refer to it as if it
1940 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1941 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1942 think csh is missing. In either case, after editing config.sh, run
1943 C<./Configure -S> and rebuild Perl.
1945 =item Glob not terminated
1947 (F) The lexer saw a left angle bracket in a place where it was expecting
1948 a term, so it's looking for the corresponding right angle bracket, and
1949 not finding it. Chances are you left some needed parentheses out
1950 earlier in the line, and you really meant a "less than".
1952 =item gmtime(%f) too large
1954 (W overflow) You called C<gmtime> with a number that was larger than
1955 it can reliably handle and C<gmtime> probably returned the wrong
1956 date. This warning is also triggered with nan (the special
1957 not-a-number value).
1959 =item gmtime(%f) too small
1961 (W overflow) You called C<gmtime> with a number that was smaller than
1962 it can reliably handle and C<gmtime> probably returned the wrong
1963 date. This warning is also triggered with nan (the special
1964 not-a-number value).
1966 =item Got an error from DosAllocMem
1968 (P) An error peculiar to OS/2. Most probably you're using an obsolete
1969 version of Perl, and this should not happen anyway.
1971 =item goto must have label
1973 (F) Unlike with "next" or "last", you're not allowed to goto an
1974 unspecified destination. See L<perlfunc/goto>.
1976 =item ()-group starts with a count
1978 (F) A ()-group started with a count. A count is supposed to follow
1979 something: a template character or a ()-group. See L<perlfunc/pack>.
1981 =item %s had compilation errors.
1983 (F) The final summary message when a C<perl -c> fails.
1985 =item Had to create %s unexpectedly
1987 (S internal) A routine asked for a symbol from a symbol table that ought
1988 to have existed already, but for some reason it didn't, and had to be
1989 created on an emergency basis to prevent a core dump.
1991 =item Hash %%s missing the % in argument %d of %s()
1993 (D deprecated) Really old Perl let you omit the % on hash names in some
1994 spots. This is now heavily deprecated.
1996 =item %s has too many errors
1998 (F) The parser has given up trying to parse the program after 10 errors.
1999 Further error messages would likely be uninformative.
2001 =item Having no space between pattern and following word is deprecated
2005 You had a word that isn't a regex modifier immediately following a pattern
2006 without an intervening space. For example, the two constructs:
2008 $a =~ m/$foo/sand $bar
2009 $a =~ m/$foo/s and $bar
2011 both currently mean the same thing, but it is planned to disallow the first
2012 form in Perl 5.16. And,
2014 $a =~ m/$foo/and $bar
2016 will be disallowed too.
2018 =item Hexadecimal number > 0xffffffff non-portable
2020 (W portable) The hexadecimal number you specified is larger than 2**32-1
2021 (4294967295) and therefore non-portable between systems. See
2022 L<perlport> for more on portability concerns.
2024 =item Identifier too long
2026 (F) Perl limits identifiers (names for variables, functions, etc.) to
2027 about 250 characters for simple names, and somewhat more for compound
2028 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2029 of Perl are likely to eliminate these arbitrary limitations.
2031 =item Ignoring zero length \N{} in character class
2033 (W) Named Unicode character escapes (\N{...}) may return a
2034 zero length sequence. When such an escape is used in a character class
2035 its behaviour is not well defined. Check that the correct escape has
2036 been used, and the correct charname handler is in scope.
2038 =item Illegal binary digit %s
2040 (F) You used a digit other than 0 or 1 in a binary number.
2042 =item Illegal binary digit %s ignored
2044 (W digit) You may have tried to use a digit other than 0 or 1 in a
2045 binary number. Interpretation of the binary number stopped before the
2048 =item Illegal character \%o (carriage return)
2050 (F) Perl normally treats carriage returns in the program text as it
2051 would any other whitespace, which means you should never see this error
2052 when Perl was built using standard options. For some reason, your
2053 version of Perl appears to have been built without this support. Talk
2054 to your Perl administrator.
2056 =item Illegal character in prototype for %s : %s
2058 (W illegalproto) An illegal character was found in a prototype declaration.
2059 Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
2061 =item Illegal declaration of anonymous subroutine
2063 (F) When using the C<sub> keyword to construct an anonymous subroutine,
2064 you must always specify a block of code. See L<perlsub>.
2066 =item Illegal declaration of subroutine %s
2068 (F) A subroutine was not declared correctly. See L<perlsub>.
2070 =item Illegal division by zero
2072 (F) You tried to divide a number by 0. Either something was wrong in
2073 your logic, or you need to put a conditional in to guard against
2076 =item Illegal hexadecimal digit %s ignored
2078 (W digit) You may have tried to use a character other than 0 - 9 or
2079 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2080 number stopped before the illegal character.
2082 =item Illegal modulus zero
2084 (F) You tried to divide a number by 0 to get the remainder. Most
2085 numbers don't take to this kindly.
2087 =item Illegal number of bits in vec
2089 (F) The number of bits in vec() (the third argument) must be a power of
2090 two from 1 to 32 (or 64, if your platform supports that).
2092 =item Illegal octal digit %s
2094 (F) You used an 8 or 9 in an octal number.
2096 =item Illegal octal digit %s ignored
2098 (W digit) You may have tried to use an 8 or 9 in an octal number.
2099 Interpretation of the octal number stopped before the 8 or 9.
2101 =item Illegal switch in PERL5OPT: -%c
2103 (X) The PERL5OPT environment variable may only be used to set the
2104 following switches: B<-[CDIMUdmtw]>.
2106 =item Ill-formed CRTL environ value "%s"
2108 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
2109 internal environ array, and encountered an element without the C<=>
2110 delimiter used to separate keys from values. The element is ignored.
2112 =item Ill-formed message in prime_env_iter: |%s|
2114 (W internal) A warning peculiar to VMS. Perl tried to read a logical
2115 name or CLI symbol definition when preparing to iterate over %ENV, and
2116 didn't see the expected delimiter between key and value, so the line was
2119 =item (in cleanup) %s
2121 (W misc) This prefix usually indicates that a DESTROY() method raised
2122 the indicated exception. Since destructors are usually called by the
2123 system at arbitrary points during execution, and often a vast number of
2124 times, the warning is issued only once for any number of failures that
2125 would otherwise result in the same message being repeated.
2127 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2128 also result in this warning. See L<perlcall/G_KEEPERR>.
2130 =item Inconsistent hierarchy during C3 merge of class '%s': merging failed on parent '%s'
2132 (F) The method resolution order (MRO) of the given class is not
2133 C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2134 documentation in L<mro> for more information.
2136 =item In EBCDIC the v-string components cannot exceed 2147483647
2138 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2139 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2140 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2142 =item Infinite recursion in regex; marked by <-- HERE in m/%s/
2144 (F) You used a pattern that references itself without consuming any input
2145 text. You should check the pattern to ensure that recursive patterns
2146 either consume text or fail.
2148 The <-- HERE shows in the regular expression about where the problem was
2151 =item Initialization of state variables in list context currently forbidden
2153 (F) Currently the implementation of "state" only permits the initialization
2154 of scalar variables in scalar context. Re-write C<state ($a) = 42> as
2155 C<state $a = 42> to change from list to scalar context. Constructions such
2156 as C<state (@a) = foo()> will be supported in a future perl release.
2158 =item Insecure dependency in %s
2160 (F) You tried to do something that the tainting mechanism didn't like.
2161 The tainting mechanism is turned on when you're running setuid or
2162 setgid, or when you specify B<-T> to turn it on explicitly. The
2163 tainting mechanism labels all data that's derived directly or indirectly
2164 from the user, who is considered to be unworthy of your trust. If any
2165 such data is used in a "dangerous" operation, you get this error. See
2166 L<perlsec> for more information.
2168 =item Insecure directory in %s
2170 (F) You can't use system(), exec(), or a piped open in a setuid or
2171 setgid script if C<$ENV{PATH}> contains a directory that is writable by
2172 the world. Also, the PATH must not contain any relative directory.
2175 =item Insecure $ENV{%s} while running %s
2177 (F) You can't use system(), exec(), or a piped open in a setuid or
2178 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
2179 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2180 supplied (or potentially supplied) by the user. The script must set
2181 the path to a known value, using trustworthy data. See L<perlsec>.
2183 =item Integer overflow in format string for %s
2185 (F) The indexes and widths specified in the format string of C<printf()>
2186 or C<sprintf()> are too large. The numbers must not overflow the size of
2187 integers for your architecture.
2189 =item Integer overflow in %s number
2191 (W overflow) The hexadecimal, octal or binary number you have specified
2192 either as a literal or as an argument to hex() or oct() is too big for
2193 your architecture, and has been converted to a floating point number.
2194 On a 32-bit architecture the largest hexadecimal, octal or binary number
2195 representable without overflow is 0xFFFFFFFF, 037777777777, or
2196 0b11111111111111111111111111111111 respectively. Note that Perl
2197 transparently promotes all numbers to a floating point representation
2198 internally--subject to loss of precision errors in subsequent
2201 =item Integer overflow in version
2203 (F) Some portion of a version initialization is too large for the
2204 size of integers for your architecture. This is not a warning
2205 because there is no rational reason for a version to try and use a
2206 element larger than typically 2**32. This is usually caused by
2207 trying to use some odd mathematical operation as a version, like
2210 =item Internal disaster in regex; marked by <-- HERE in m/%s/
2212 (P) Something went badly wrong in the regular expression parser.
2213 The <-- HERE shows in the regular expression about where the problem was
2216 =item Internal inconsistency in tracking vforks
2218 (S) A warning peculiar to VMS. Perl keeps track of the number of times
2219 you've called C<fork> and C<exec>, to determine whether the current call
2220 to C<exec> should affect the current script or a subprocess (see
2221 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2222 Perl is making a guess and treating this C<exec> as a request to
2223 terminate the Perl script and execute the specified command.
2225 =item Internal urp in regex; marked by <-- HERE in m/%s/
2227 (P) Something went badly awry in the regular expression parser. The
2228 <-- HERE shows in the regular expression about where the problem was
2231 =item %s (...) interpreted as function
2233 (W syntax) You've run afoul of the rule that says that any list operator
2234 followed by parentheses turns into a function, with all the list
2235 operators arguments found inside the parentheses. See
2236 L<perlop/Terms and List Operators (Leftward)>.
2238 =item Invalid %s attribute: %s
2240 (F) The indicated attribute for a subroutine or variable was not recognized
2241 by Perl or by a user-supplied handler. See L<attributes>.
2243 =item Invalid %s attributes: %s
2245 (F) The indicated attributes for a subroutine or variable were not
2246 recognized by Perl or by a user-supplied handler. See L<attributes>.
2248 =item Invalid conversion in %s: "%s"
2250 (W printf) Perl does not understand the given format conversion. See
2251 L<perlfunc/sprintf>.
2253 =item Invalid escape in the specified encoding in regex; marked by <-- HERE in m/%s/
2255 (W regexp) The numeric escape (for example C<\xHH>) of value < 256
2256 didn't correspond to a single character through the conversion
2257 from the encoding specified by the encoding pragma.
2258 The escape was replaced with REPLACEMENT CHARACTER (U+FFFD) instead.
2259 The <-- HERE shows in the regular expression about where the
2260 escape was discovered.
2262 =item Invalid hexadecimal number in \N{U+...}
2264 (F) The character constant represented by C<...> is not a valid hexadecimal
2265 number. Either it is empty, or you tried to use a character other than
2266 0 - 9 or A - F, a - f in a hexadecimal number.
2268 =item Invalid mro name: '%s'
2270 (F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2271 where C<foo> is not a valid method resolution order (MRO). Currently,
2272 the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2273 a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2275 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
2277 (F) The range specified in a character class had a minimum character
2278 greater than the maximum character. One possibility is that you forgot the
2279 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
2280 up to C<ff>. The <-- HERE shows in the regular expression about where the
2281 problem was discovered. See L<perlre>.
2283 =item Invalid range "%s" in transliteration operator
2285 (F) The range specified in the tr/// or y/// operator had a minimum
2286 character greater than the maximum character. See L<perlop>.
2288 =item Invalid separator character %s in attribute list
2290 (F) Something other than a colon or whitespace was seen between the
2291 elements of an attribute list. If the previous attribute had a
2292 parenthesised parameter list, perhaps that list was terminated too soon.
2295 =item Invalid separator character %s in PerlIO layer specification %s
2297 (W layer) When pushing layers onto the Perl I/O system, something other
2298 than a colon or whitespace was seen between the elements of a layer list.
2299 If the previous attribute had a parenthesised parameter list, perhaps that
2300 list was terminated too soon.
2302 =item Invalid strict version format (%s)
2304 (F) A version number did not meet the "strict" criteria for versions.
2305 A "strict" version number is a positive decimal number (integer or
2306 decimal-fraction) without exponentiation or else a dotted-decimal
2307 v-string with a leading 'v' character and at least three components.
2308 The parenthesized text indicates which criteria were not met.
2309 See the L<version> module for more details on allowed version formats.
2311 =item Invalid type '%s' in %s
2313 (F) The given character is not a valid pack or unpack type.
2314 See L<perlfunc/pack>.
2315 (W) The given character is not a valid pack or unpack type but used to be
2318 =item Invalid version format (%s)
2320 (F) A version number did not meet the "lax" criteria for versions.
2321 A "lax" version number is a positive decimal number (integer or
2322 decimal-fraction) without exponentiation or else a dotted-decimal
2323 v-string. If the v-string has fewer than three components, it must
2324 have a leading 'v' character. Otherwise, the leading 'v' is optional.
2325 Both decimal and dotted-decimal versions may have a trailing "alpha"
2326 component separated by an underscore character after a fractional or
2327 dotted-decimal component. The parenthesized text indicates which
2328 criteria were not met. See the L<version> module for more details on
2329 allowed version formats.
2331 =item Invalid version object
2333 (F) The internal structure of the version object was invalid. Perhaps
2334 the internals were modified directly in some way or an arbitrary reference
2335 was blessed into the "version" class.
2337 =item ioctl is not implemented
2339 (F) Your machine apparently doesn't implement ioctl(), which is pretty
2340 strange for a machine that supports C.
2342 =item ioctl() on unopened %s
2344 (W unopened) You tried ioctl() on a filehandle that was never opened.
2345 Check your control flow and number of arguments.
2347 =item IO layers (like '%s') unavailable
2349 (F) Your Perl has not been configured to have PerlIO, and therefore
2350 you cannot use IO layers. To have PerlIO, Perl must be configured
2353 =item IO::Socket::atmark not implemented on this architecture
2355 (F) Your machine doesn't implement the sockatmark() functionality,
2356 neither as a system call nor an ioctl call (SIOCATMARK).
2358 =item $* is no longer supported
2360 (D deprecated, syntax) The special variable C<$*>, deprecated in older
2361 perls, has been removed as of 5.9.0 and is no longer supported. In
2362 previous versions of perl the use of C<$*> enabled or disabled multi-line
2363 matching within a string.
2365 Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
2366 modifiers. You can enable C</m> for a lexical scope (even a whole file)
2367 with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
2368 then all regular expressions behaved as if they were written using C</m>.)
2370 =item $# is no longer supported
2372 (D deprecated, syntax) The special variable C<$#>, deprecated in older
2373 perls, has been removed as of 5.9.3 and is no longer supported. You
2374 should use the printf/sprintf functions instead.
2376 =item `%s' is not a code reference
2378 (W overload) The second (fourth, sixth, ...) argument of overload::constant
2379 needs to be a code reference. Either an anonymous subroutine, or a reference
2382 =item `%s' is not an overloadable type
2384 (W overload) You tried to overload a constant type the overload package is
2387 =item junk on end of regexp
2389 (P) The regular expression parser is confused.
2391 =item Label not found for "last %s"
2393 (F) You named a loop to break out of, but you're not currently in a loop
2394 of that name, not even if you count where you were called from. See
2397 =item Label not found for "next %s"
2399 (F) You named a loop to continue, but you're not currently in a loop of
2400 that name, not even if you count where you were called from. See
2403 =item Label not found for "redo %s"
2405 (F) You named a loop to restart, but you're not currently in a loop of
2406 that name, not even if you count where you were called from. See
2409 =item leaving effective %s failed
2411 (F) While under the C<use filetest> pragma, switching the real and
2412 effective uids or gids failed.
2414 =item length/code after end of string in unpack
2416 (F) While unpacking, the string buffer was already used up when an unpack
2417 length/code combination tried to obtain more data. This results in
2418 an undefined value for the length. See L<perlfunc/pack>.
2420 =item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2422 (F) An extension is attempting to insert text into the current parse
2423 (using L<lex_stuff_pvn_flags|perlapi/lex_stuff_pvn_flags> or similar), but tried to insert a character
2424 that couldn't be part of the current input. This is an inherent pitfall
2425 of the stuffing mechanism, and one of the reasons to avoid it. Where it
2426 is necessary to stuff, stuffing only plain ASCII is recommended.
2428 =item Lexing code internal error (%s)
2430 (F) Lexing code supplied by an extension violated the lexer's API in a
2433 =item listen() on closed socket %s
2435 (W closed) You tried to do a listen on a closed socket. Did you forget
2436 to check the return value of your socket() call? See
2439 =item localtime(%f) too large
2441 (W overflow) You called C<localtime> with a number that was larger
2442 than it can reliably handle and C<localtime> probably returned the
2443 wrong date. This warning is also triggered with nan (the special
2444 not-a-number value).
2446 =item localtime(%f) too small
2448 (W overflow) You called C<localtime> with a number that was smaller
2449 than it can reliably handle and C<localtime> probably returned the
2450 wrong date. This warning is also triggered with nan (the special
2451 not-a-number value).
2453 =item Lookbehind longer than %d not implemented in regex m/%s/
2455 (F) There is currently a limit on the length of string which lookbehind can
2456 handle. This restriction may be eased in a future release.
2458 =item Lost precision when %s %f by 1
2460 (W) The value you attempted to increment or decrement by one is too large
2461 for the underlying floating point representation to store accurately,
2462 hence the target of C<++> or C<--> is unchanged. Perl issues this warning
2463 because it has already switched from integers to floating point when values
2464 are too large for integers, and now even floating point is insufficient.
2465 You may wish to switch to using L<Math::BigInt> explicitly.
2467 =item lstat() on filehandle %s
2469 (W io) You tried to do an lstat on a filehandle. What did you mean
2470 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2471 instead on the filehandle.)
2473 =item lvalue attribute ignored after the subroutine has been defined
2475 (W misc) Making a subroutine an lvalue subroutine after it has been defined
2476 by declaring the subroutine with an lvalue attribute is not
2477 possible. To make the subroutine an lvalue subroutine add the
2478 lvalue attribute to the definition, or put the declaration before
2481 =item Lvalue subs returning %s not implemented yet
2483 (F) Due to limitations in the current implementation, array and hash
2484 values cannot be returned in subroutines used in lvalue context. See
2485 L<perlsub/"Lvalue subroutines">.
2487 =item Malformed integer in [] in pack
2489 (F) Between the brackets enclosing a numeric repeat count only digits
2490 are permitted. See L<perlfunc/pack>.
2492 =item Malformed integer in [] in unpack
2494 (F) Between the brackets enclosing a numeric repeat count only digits
2495 are permitted. See L<perlfunc/pack>.
2497 =item Malformed PERLLIB_PREFIX
2499 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2506 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2507 a builtin library search path, prefix2 is substituted. The error may
2508 appear if components are not found, or are too long. See
2509 "PERLLIB_PREFIX" in L<perlos2>.
2511 =item Malformed prototype for %s: %s
2513 (F) You tried to use a function with a malformed prototype. The
2514 syntax of function prototypes is given a brief compile-time check for
2515 obvious errors like invalid characters. A more rigorous check is run
2516 when the function is called.
2518 =item Malformed UTF-8 character (%s)
2520 (S utf8) (F) Perl detected a string that didn't comply with UTF-8
2521 encoding rules, even though it had the UTF8 flag on.
2523 One possible cause is that you set the UTF8 flag yourself for data that
2524 you thought to be in UTF-8 but it wasn't (it was for example legacy
2525 8-bit data). To guard against this, you can use Encode::decode_utf8.
2527 If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2528 sequences are handled gracefully, but if you use C<:utf8>, the flag is
2529 set without validating the data, possibly resulting in this error
2532 See also L<Encode/"Handling Malformed Data">.
2534 =item Malformed UTF-8 returned by \N
2536 (F) The charnames handler returned malformed UTF-8.
2538 =item Malformed UTF-8 string in '%c' format in unpack
2540 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2541 rules and perl was unable to guess how to make more progress.
2543 =item Malformed UTF-8 string in pack
2545 (F) You tried to pack something that didn't comply with UTF-8 encoding
2546 rules and perl was unable to guess how to make more progress.
2548 =item Malformed UTF-8 string in unpack
2550 (F) You tried to unpack something that didn't comply with UTF-8 encoding
2551 rules and perl was unable to guess how to make more progress.
2553 =item Malformed UTF-16 surrogate
2555 (F) Perl thought it was reading UTF-16 encoded character data but while
2556 doing it Perl met a malformed Unicode surrogate.
2558 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2560 (W regexp) The pattern you've specified would be an infinite loop if the
2561 regular expression engine didn't specifically check for that. The <-- HERE
2562 shows in the regular expression about where the problem was discovered.
2565 =item Maximal count of pending signals (%u) exceeded
2567 (F) Perl aborted due to too high a number of signals pending. This
2568 usually indicates that your operating system tried to deliver signals
2569 too fast (with a very high priority), starving the perl process from
2570 resources it would need to reach a point where it can process signals
2571 safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2573 =item "%s" may clash with future reserved word
2575 (W) This warning may be due to running a perl5 script through a perl4
2576 interpreter, especially if the word that is being warned about is
2579 =item % may not be used in pack
2581 (F) You can't pack a string by supplying a checksum, because the
2582 checksumming process loses information, and you can't go the other way.
2583 See L<perlfunc/unpack>.
2585 =item Method for operation %s not found in package %s during blessing
2587 (F) An attempt was made to specify an entry in an overloading table that
2588 doesn't resolve to a valid subroutine. See L<overload>.
2590 =item Method %s not permitted
2594 =item Might be a runaway multi-line %s string starting on line %d
2596 (S) An advisory indicating that the previous error may have been caused
2597 by a missing delimiter on a string or pattern, because it eventually
2598 ended earlier on the current line.
2600 =item Misplaced _ in number
2602 (W syntax) An underscore (underbar) in a numeric constant did not
2603 separate two digits.
2605 =item Missing argument in %s
2607 (W uninitialized) A printf-type format required more arguments than were
2610 =item Missing argument to -%c
2612 (F) The argument to the indicated command line switch must follow
2613 immediately after the switch, without intervening spaces.
2615 =item Missing braces on \N{}
2617 (F) Wrong syntax of character name literal C<\N{charname}> within
2618 double-quotish context. This can also happen when there is a space
2619 (or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
2620 This modifier does not change the requirement that the brace immediately
2623 =item Missing braces on \o{}
2625 (F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
2627 =item Missing comma after first argument to %s function
2629 (F) While certain functions allow you to specify a filehandle or an
2630 "indirect object" before the argument list, this ain't one of them.
2632 =item Missing command in piped open
2634 (W pipe) You used the C<open(FH, "| command")> or
2635 C<open(FH, "command |")> construction, but the command was missing or
2638 =item Missing control char name in \c
2640 (F) A double-quoted string ended with "\c", without the required control
2643 =item Missing name in "my sub"
2645 (F) The reserved syntax for lexically scoped subroutines requires that
2646 they have a name with which they can be found.
2648 =item Missing $ on loop variable
2650 (F) Apparently you've been programming in B<csh> too much. Variables
2651 are always mentioned with the $ in Perl, unlike in the shells, where it
2652 can vary from one line to the next.
2654 =item (Missing operator before %s?)
2656 (S syntax) This is an educated guess made in conjunction with the message
2657 "%s found where operator expected". Often the missing operator is a comma.
2659 =item Missing right brace on %s
2661 (F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
2663 =item Missing right brace on \N{} or unescaped left brace after \N
2665 (F) C<\N> has two meanings.
2667 The traditional one has it followed by a name enclosed in braces,
2668 meaning the character (or sequence of characters) given by that
2669 name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
2670 double-quoted strings and regular expression patterns. In patterns,
2671 it doesn't have the meaning an unescaped C<*> does.
2673 Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
2674 in patterns, namely to match a non-newline character. (This is short
2675 for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
2677 This can lead to some ambiguities. When C<\N> is not followed immediately
2678 by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
2679 form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
2680 means to match the given quantity of non-newlines (in these examples,
2681 3; and 5 or more, respectively). In all other case, where there is a
2682 C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
2684 However, if there is no matching C<}>, Perl doesn't know if it was
2685 mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
2686 If you meant the former, add the right brace; if you meant the latter,
2687 escape the brace with a backslash, like so: C<\N\{>
2689 =item Missing right curly or square bracket
2691 (F) The lexer counted more opening curly or square brackets than closing
2692 ones. As a general rule, you'll find it's missing near the place you
2695 =item (Missing semicolon on previous line?)
2697 (S syntax) This is an educated guess made in conjunction with the message
2698 "%s found where operator expected". Don't automatically put a semicolon on
2699 the previous line just because you saw this message.
2701 =item Modification of a read-only value attempted
2703 (F) You tried, directly or indirectly, to change the value of a
2704 constant. You didn't, of course, try "2 = 1", because the compiler
2705 catches that. But an easy way to do the same thing is:
2707 sub mod { $_[0] = 1 }
2710 Another way is to assign to a substr() that's off the end of the string.
2712 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2713 is aliased to a constant in the look I<LIST>:
2716 foreach my $n ($x, 2) {
2717 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2720 =item Modification of non-creatable array value attempted, %s
2722 (F) You tried to make an array value spring into existence, and the
2723 subscript was probably negative, even counting from end of the array
2726 =item Modification of non-creatable hash value attempted, %s
2728 (P) You tried to make a hash value spring into existence, and it
2729 couldn't be created for some peculiar reason.
2731 =item Module name must be constant
2733 (F) Only a bare module name is allowed as the first argument to a "use".
2735 =item Module name required with -%c option
2737 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2738 you omitted the name of the module. Consult L<perlrun> for full details
2739 about C<-M> and C<-m>.
2741 =item More than one argument to '%s' open
2743 (F) The C<open> function has been asked to open multiple files. This
2744 can happen if you are trying to open a pipe to a command that takes a
2745 list of arguments, but have forgotten to specify a piped open mode.
2746 See L<perlfunc/open> for details.
2748 =item msg%s not implemented
2750 (F) You don't have System V message IPC on your system.
2752 =item Multidimensional syntax %s not supported
2754 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2755 They're written like C<$foo[1][2][3]>, as in C.
2757 =item '/' must follow a numeric type in unpack
2759 (F) You had an unpack template that contained a '/', but this did not
2760 follow some unpack specification producing a numeric value.
2761 See L<perlfunc/pack>.
2763 =item "my sub" not yet implemented
2765 (F) Lexically scoped subroutines are not yet implemented. Don't try
2768 =item "my" variable %s can't be in a package
2770 (F) Lexically scoped variables aren't in a package, so it doesn't make
2771 sense to try to declare one with a package qualifier on the front. Use
2772 local() if you want to localize a package variable.
2774 =item Name "%s::%s" used only once: possible typo
2776 (W once) Typographical errors often show up as unique variable names.
2777 If you had a good reason for having a unique name, then just mention it
2778 again somehow to suppress the message. The C<our> declaration is
2779 provided for this purpose.
2781 NOTE: This warning detects symbols that have been used only once so $c, @c,
2782 %c, *c, &c, sub c{}, c(), and c (the filehandle or format) are considered
2783 the same; if a program uses $c only once but also uses any of the others it
2784 will not trigger this warning.
2786 =item \N in a character class must be a named character: \N{...}
2788 (F) The new (5.12) meaning of C<\N> as C<[^\n]> is not valid in a bracketed
2789 character class, for the same reason that C<.> in a character class loses
2790 its specialness: it matches almost everything, which is probably not
2793 =item \N{NAME} must be resolved by the lexer
2795 (F) When compiling a regex pattern, an unresolved named character or
2796 sequence was encountered. This can happen in any of several ways that
2797 bypass the lexer, such as using single-quotish context, or an extra
2798 backslash in double-quotish:
2800 $re = '\N{SPACE}'; # Wrong!
2801 $re = "\\N{SPACE}"; # Wrong!
2804 Instead, use double-quotes with a single backslash:
2806 $re = "\N{SPACE}"; # ok
2809 The lexer can be bypassed as well by creating the pattern from smaller
2813 /${re}{SPACE}/; # Wrong!
2815 It's not a good idea to split a construct in the middle like this, and it
2816 doesn't work here. Instead use the solution above.
2818 Finally, the message also can happen under the C</x> regex modifier when the
2819 C<\N> is separated by spaces from the C<{>, in which case, remove the spaces.
2821 /\N {SPACE}/x; # Wrong!
2824 =item Negative '/' count in unpack
2826 (F) The length count obtained from a length/code unpack operation was
2827 negative. See L<perlfunc/pack>.
2829 =item Negative length
2831 (F) You tried to do a read/write/send/recv operation with a buffer
2832 length that is less than 0. This is difficult to imagine.
2834 =item Negative offset to vec in lvalue context
2836 (F) When C<vec> is called in an lvalue context, the second argument must be
2837 greater than or equal to zero.
2839 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2841 (F) You can't quantify a quantifier without intervening parentheses. So
2842 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2843 expression about where the problem was discovered.
2845 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2846 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2848 =item %s never introduced
2850 (S internal) The symbol in question was declared but somehow went out of
2851 scope before it could possibly have been used.
2853 =item next::method/next::can/maybe::next::method cannot find enclosing method
2855 (F) C<next::method> needs to be called within the context of a
2856 real method in a real package, and it could not find such a context.
2859 =item No %s allowed while running setuid
2861 (F) Certain operations are deemed to be too insecure for a setuid or
2862 setgid script to even be allowed to attempt. Generally speaking there
2863 will be another way to do what you want that is, if not secure, at least
2864 securable. See L<perlsec>.
2866 =item No comma allowed after %s
2868 (F) A list operator that has a filehandle or "indirect object" is not
2869 allowed to have a comma between that and the following arguments.
2870 Otherwise it'd be just another one of the arguments.
2872 One possible cause for this is that you expected to have imported a
2873 constant to your name space with B<use> or B<import> while no such
2874 importing took place, it may for example be that your operating system
2875 does not support that particular constant. Hopefully you did use an
2876 explicit import list for the constants you expect to see; please see
2877 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2878 would probably have caught this error earlier it naturally does not
2879 remedy the fact that your operating system still does not support that
2880 constant. Maybe you have a typo in the constants of the symbol import
2881 list of B<use> or B<import> or in the constant name at the line where
2882 this error was triggered?
2884 =item No command into which to pipe on command line
2886 (F) An error peculiar to VMS. Perl handles its own command line
2887 redirection, and found a '|' at the end of the command line, so it
2888 doesn't know where you want to pipe the output from this command.
2890 =item No DB::DB routine defined
2892 (F) The currently executing code was compiled with the B<-d> switch, but
2893 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
2894 module) didn't define a routine to be called at the beginning of each
2897 =item No dbm on this machine
2899 (P) This is counted as an internal error, because every machine should
2900 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2902 =item No DB::sub routine defined
2904 (F) The currently executing code was compiled with the B<-d> switch, but
2905 for some reason the current debugger (e.g. F<perl5db.pl> or a C<Devel::>
2906 module) didn't define a C<DB::sub> routine to be called at the beginning
2907 of each ordinary subroutine call.
2909 =item No B<-e> allowed in setuid scripts
2911 (F) A setuid script can't be specified by the user.
2913 =item No error file after 2> or 2>> on command line
2915 (F) An error peculiar to VMS. Perl handles its own command line
2916 redirection, and found a '2>' or a '2>>' on the command line, but can't
2917 find the name of the file to which to write data destined for stderr.
2919 =item No group ending character '%c' found in template
2921 (F) A pack or unpack template has an opening '(' or '[' without its
2922 matching counterpart. See L<perlfunc/pack>.
2924 =item No input file after < on command line
2926 (F) An error peculiar to VMS. Perl handles its own command line
2927 redirection, and found a '<' on the command line, but can't find the
2928 name of the file from which to read data for stdin.
2932 (F) The setuid emulator requires that scripts have a well-formed #! line
2933 even on machines that don't support the #! construct.
2935 =item No next::method '%s' found for %s
2937 (F) C<next::method> found no further instances of this method name
2938 in the remaining packages of the MRO of this class. If you don't want
2939 it throwing an exception, use C<maybe::next::method>
2940 or C<next::can>. See L<mro>.
2942 =item "no" not allowed in expression
2944 (F) The "no" keyword is recognized and executed at compile time, and
2945 returns no useful value. See L<perlmod>.
2947 =item No output file after > on command line
2949 (F) An error peculiar to VMS. Perl handles its own command line
2950 redirection, and found a lone '>' at the end of the command line, so it
2951 doesn't know where you wanted to redirect stdout.
2953 =item No output file after > or >> on command line
2955 (F) An error peculiar to VMS. Perl handles its own command line
2956 redirection, and found a '>' or a '>>' on the command line, but can't
2957 find the name of the file to which to write data destined for stdout.
2959 =item No package name allowed for variable %s in "our"
2961 (F) Fully qualified variable names are not allowed in "our"
2962 declarations, because that doesn't make much sense under existing
2963 semantics. Such syntax is reserved for future extensions.
2965 =item No Perl script found in input
2967 (F) You called C<perl -x>, but no line was found in the file beginning
2968 with #! and containing the word "perl".
2970 =item No setregid available
2972 (F) Configure didn't find anything resembling the setregid() call for
2975 =item No setreuid available
2977 (F) Configure didn't find anything resembling the setreuid() call for
2980 =item No %s specified for -%c
2982 (F) The indicated command line switch needs a mandatory argument, but
2983 you haven't specified one.
2985 =item No such class field "%s" in variable %s of type %s
2987 (F) You tried to access a key from a hash through the indicated typed variable
2988 but that key is not allowed by the package of the same type. The indicated
2989 package has restricted the set of allowed keys using the L<fields> pragma.
2991 =item No such class %s
2993 (F) You provided a class qualifier in a "my", "our" or "state"
2994 declaration, but this class doesn't exist at this point in your program.
2996 =item No such hook: %s
2998 (F) You specified a signal hook that was not recognized by Perl.
2999 Currently, Perl accepts C<__DIE__> and C<__WARN__> as valid signal hooks.
3001 =item No such pipe open
3003 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
3004 close a pipe which hadn't been opened. This should have been caught
3005 earlier as an attempt to close an unopened filehandle.
3007 =item No such signal: SIG%s
3009 (W signal) You specified a signal name as a subscript to %SIG that was
3010 not recognized. Say C<kill -l> in your shell to see the valid signal
3011 names on your system.
3013 =item Not a CODE reference
3015 (F) Perl was trying to evaluate a reference to a code value (that is, a
3016 subroutine), but found a reference to something else instead. You can
3017 use the ref() function to find out what kind of ref it really was. See
3020 =item Not a format reference
3022 (F) I'm not sure how you managed to generate a reference to an anonymous
3023 format, but this indicates you did, and that it didn't exist.
3025 =item Not a GLOB reference
3027 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
3028 symbol table entry that looks like C<*foo>), but found a reference to
3029 something else instead. You can use the ref() function to find out what
3030 kind of ref it really was. See L<perlref>.
3032 =item Not a HASH reference
3034 (F) Perl was trying to evaluate a reference to a hash value, but found a
3035 reference to something else instead. You can use the ref() function to
3036 find out what kind of ref it really was. See L<perlref>.
3038 =item Not an ARRAY reference
3040 (F) Perl was trying to evaluate a reference to an array value, but found
3041 a reference to something else instead. You can use the ref() function
3042 to find out what kind of ref it really was. See L<perlref>.
3044 =item Not a perl script
3046 (F) The setuid emulator requires that scripts have a well-formed #! line
3047 even on machines that don't support the #! construct. The line must
3050 =item Not a SCALAR reference
3052 (F) Perl was trying to evaluate a reference to a scalar value, but found
3053 a reference to something else instead. You can use the ref() function
3054 to find out what kind of ref it really was. See L<perlref>.
3056 =item Not a subroutine reference
3058 (F) Perl was trying to evaluate a reference to a code value (that is, a
3059 subroutine), but found a reference to something else instead. You can
3060 use the ref() function to find out what kind of ref it really was. See
3063 =item Not a subroutine reference in overload table
3065 (F) An attempt was made to specify an entry in an overloading table that
3066 doesn't somehow point to a valid subroutine. See L<overload>.
3068 =item Not enough arguments for %s
3070 (F) The function requires more arguments than you specified.
3072 =item Not enough format arguments
3074 (W syntax) A format specified more picture fields than the next line
3075 supplied. See L<perlform>.
3079 (A) You've accidentally run your script through the Bourne shell instead
3080 of Perl. Check the #! line, or manually feed your script into Perl
3083 =item no UTC offset information; assuming local time is UTC
3085 (S) A warning peculiar to VMS. Perl was unable to find the local
3086 timezone offset, so it's assuming that local system time is equivalent
3087 to UTC. If it's not, define the logical name
3088 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
3089 need to be added to UTC to get local time.
3091 =item Non-octal character '%c'. Resolved as "%s"
3093 (W digit) In parsing an octal numeric constant, a character was
3094 unexpectedly encountered that isn't octal. The resulting value is as
3097 =item Non-string passed as bitmask
3099 (W misc) A number has been passed as a bitmask argument to select().
3100 Use the vec() function to construct the file descriptor bitmasks for
3101 select. See L<perlfunc/select>.
3103 =item Null filename used
3105 (F) You can't require the null filename, especially because on many
3106 machines that means the current directory! See L<perlfunc/require>.
3108 =item NULL OP IN RUN
3110 (P debugging) Some internal routine called run() with a null opcode
3113 =item Null picture in formline
3115 (F) The first argument to formline must be a valid format picture
3116 specification. It was found to be empty, which probably means you
3117 supplied it an uninitialized value. See L<perlform>.
3121 (P) An attempt was made to realloc NULL.
3123 =item NULL regexp argument
3125 (P) The internal pattern matching routines blew it big time.
3127 =item NULL regexp parameter
3129 (P) The internal pattern matching routines are out of their gourd.
3131 =item Number too long
3133 (F) Perl limits the representation of decimal numbers in programs to
3134 about 250 characters. You've exceeded that length. Future
3135 versions of Perl are likely to eliminate this arbitrary limitation. In
3136 the meantime, try using scientific notation (e.g. "1e6" instead of
3139 =item Number with no digits
3141 (F) Perl was looking for a number but found nothing that looked like
3142 a number. This happens, for example with C<\o{}>, with no number between
3145 =item Octal number in vector unsupported
3147 (F) Numbers with a leading C<0> are not currently allowed in vectors.
3148 The octal number interpretation of such numbers may be supported in a
3151 =item Octal number > 037777777777 non-portable
3153 (W portable) The octal number you specified is larger than 2**32-1
3154 (4294967295) and therefore non-portable between systems. See
3155 L<perlport> for more on portability concerns.
3157 =item Odd number of arguments for overload::constant
3159 (W overload) The call to overload::constant contained an odd number of
3160 arguments. The arguments should come in pairs.
3162 =item Odd number of elements in anonymous hash
3164 (W misc) You specified an odd number of elements to initialize a hash,
3165 which is odd, because hashes come in key/value pairs.
3167 =item Odd number of elements in hash assignment
3169 (W misc) You specified an odd number of elements to initialize a hash,
3170 which is odd, because hashes come in key/value pairs.
3172 =item Offset outside string
3174 (F|W layer) You tried to do a read/write/send/recv/seek operation
3175 with an offset pointing outside the buffer. This is difficult to
3176 imagine. The sole exceptions to this are that zero padding will
3177 take place when going past the end of the string when either
3178 C<sysread()>ing a file, or when seeking past the end of a scalar opened
3179 for I/O (in anticipation of future reads and to imitate the behaviour
3182 =item %s() on unopened %s
3184 (W unopened) An I/O operation was attempted on a filehandle that was
3185 never initialized. You need to do an open(), a sysopen(), or a socket()
3186 call, or call a constructor from the FileHandle package.
3188 =item -%s on unopened filehandle %s
3190 (W unopened) You tried to invoke a file test operator on a filehandle
3191 that isn't open. Check your control flow. See also L<perlfunc/-X>.
3195 (S internal) An internal warning that the grammar is screwed up.
3199 (S internal) An internal warning that the grammar is screwed up.
3201 =item Opening dirhandle %s also as a file
3203 (W io, deprecated) You used open() to associate a filehandle to
3204 a symbol (glob or scalar) that already holds a dirhandle.
3205 Although legal, this idiom might render your code confusing
3208 =item Opening filehandle %s also as a directory
3210 (W io, deprecated) You used opendir() to associate a dirhandle to
3211 a symbol (glob or scalar) that already holds a filehandle.
3212 Although legal, this idiom might render your code confusing
3215 =item Operation "%s": no method found, %s
3217 (F) An attempt was made to perform an overloaded operation for which no
3218 handler was defined. While some handlers can be autogenerated in terms
3219 of other handlers, there is no default handler for any operation, unless
3220 the C<fallback> overloading key is specified to be true. See L<overload>.
3222 =item Operation "%s" returns its argument for non-Unicode code point 0x%X
3224 (W) You performed an operation requiring Unicode semantics on a code
3225 point that is not in Unicode, so what it should do is not defined. Perl
3226 has chosen to have it do nothing, and warn you.
3228 If the operation shown is "ToFold", it means that case-insensitive
3229 matching in a regular expression was done on the code point.
3231 If you know what you are doing you can turn off this warning by
3232 C<no warnings 'utf8';>.
3234 =item Operation "%s" returns its argument for UTF-16 surrogate U+%X
3236 (W) You performed an operation requiring Unicode semantics on a Unicode
3237 surrogate. Unicode frowns upon the use of surrogates for anything but
3238 storing strings in UTF-16, but semantics are (reluctantly) defined for
3239 the surrogates, and they are to do nothing for this operation. Because
3240 the use of surrogates can be dangerous, Perl warns.
3242 If the operation shown is "ToFold", it means that case-insensitive
3243 matching in a regular expression was done on the code point.
3245 If you know what you are doing you can turn off this warning by
3246 C<no warnings 'utf8';>.
3248 =item Operator or semicolon missing before %s
3250 (S ambiguous) You used a variable or subroutine call where the parser
3251 was expecting an operator. The parser has assumed you really meant to
3252 use an operator, but this is highly likely to be incorrect. For
3253 example, if you say "*foo *foo" it will be interpreted as if you said
3256 =item "our" variable %s redeclared
3258 (W misc) You seem to have already declared the same global once before
3259 in the current lexical scope.
3261 =item Out of memory!
3263 (X) The malloc() function returned 0, indicating there was insufficient
3264 remaining memory (or virtual memory) to satisfy the request. Perl has
3265 no option but to exit immediately.
3267 At least in Unix you may be able to get past this by increasing your
3268 process datasize limits: in csh/tcsh use C<limit> and
3269 C<limit datasize n> (where C<n> is the number of kilobytes) to check
3270 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
3271 and C<ulimit -d n>, respectively.
3273 =item Out of memory during %s extend
3275 (X) An attempt was made to extend an array, a list, or a string beyond
3276 the largest possible memory allocation.
3278 =item Out of memory during "large" request for %s
3280 (F) The malloc() function returned 0, indicating there was insufficient
3281 remaining memory (or virtual memory) to satisfy the request. However,
3282 the request was judged large enough (compile-time default is 64K), so a
3283 possibility to shut down by trapping this error is granted.
3285 =item Out of memory during request for %s
3287 (X|F) The malloc() function returned 0, indicating there was
3288 insufficient remaining memory (or virtual memory) to satisfy the
3291 The request was judged to be small, so the possibility to trap it
3292 depends on the way perl was compiled. By default it is not trappable.
3293 However, if compiled for this, Perl may use the contents of C<$^M> as an
3294 emergency pool after die()ing with this message. In this case the error
3295 is trappable I<once>, and the error message will include the line and file
3296 where the failed request happened.
3298 =item Out of memory during ridiculously large request
3300 (F) You can't allocate more than 2^31+"small amount" bytes. This error
3301 is most likely to be caused by a typo in the Perl program. e.g.,
3302 C<$arr[time]> instead of C<$arr[$time]>.
3304 =item Out of memory for yacc stack
3306 (F) The yacc parser wanted to grow its stack so it could continue
3307 parsing, but realloc() wouldn't give it more memory, virtual or
3310 =item '.' outside of string in pack
3312 (F) The argument to a '.' in your template tried to move the working
3313 position to before the start of the packed string being built.
3315 =item '@' outside of string in unpack
3317 (F) You had a template that specified an absolute position outside
3318 the string being unpacked. See L<perlfunc/pack>.
3320 =item '@' outside of string with malformed UTF-8 in unpack
3322 (F) You had a template that specified an absolute position outside
3323 the string being unpacked. The string being unpacked was also invalid
3324 UTF-8. See L<perlfunc/pack>.
3326 =item Overloaded dereference did not return a reference
3328 (F) An object with an overloaded dereference operator was dereferenced,
3329 but the overloaded operation did not return a reference. See
3332 =item Overloaded qr did not return a REGEXP
3334 (F) An object with a C<qr> overload was used as part of a match, but the
3335 overloaded operation didn't return a compiled regexp. See L<overload>.
3337 =item %s package attribute may clash with future reserved word: %s
3339 (W reserved) A lowercase attribute name was used that had a
3340 package-specific handler. That name might have a meaning to Perl itself
3341 some day, even though it doesn't yet. Perhaps you should use a
3342 mixed-case attribute name, instead. See L<attributes>.
3344 =item pack/unpack repeat count overflow
3346 (F) You can't specify a repeat count so large that it overflows your
3347 signed integers. See L<perlfunc/pack>.
3351 (W io) A single call to write() produced more lines than can fit on a
3352 page. See L<perlform>.
3356 (P) An internal error.
3358 =item panic: attempt to call %s in %s
3360 (P) One of the file test operators entered a code branch that calls
3361 an ACL related-function, but that function is not available on this
3362 platform. Earlier checks mean that it should not be possible to
3363 enter this branch on this platform.
3365 =item panic: ck_grep
3367 (P) Failed an internal consistency check trying to compile a grep.
3369 =item panic: ck_split
3371 (P) Failed an internal consistency check trying to compile a split.
3373 =item panic: corrupt saved stack index
3375 (P) The savestack was requested to restore more localized values than
3376 there are in the savestack.
3378 =item panic: del_backref
3380 (P) Failed an internal consistency check while trying to reset a weak
3383 =item panic: Devel::DProf inconsistent subroutine return
3385 (P) Devel::DProf called a subroutine that exited using goto(LABEL),
3386 last(LABEL) or next(LABEL). Leaving that way a subroutine called from
3387 an XSUB will lead very probably to a crash of the interpreter. This is
3388 a bug that will hopefully one day get fixed.
3392 (P) We popped the context stack to an eval context, and then discovered
3393 it wasn't an eval context.
3395 =item panic: do_subst
3397 (P) The internal pp_subst() routine was called with invalid operational
3400 =item panic: do_trans_%s
3402 (P) The internal do_trans routines were called with invalid operational
3405 =item panic: fold_constants JMPENV_PUSH returned %d
3407 (P) While attempting folding constants an exception other than an C<eval>
3412 (P) The library function frexp() failed, making printf("%f") impossible.
3416 (P) We popped the context stack to a context with the specified label,
3417 and then discovered it wasn't a context we know how to do a goto in.
3419 =item panic: gp_free failed to free glob pointer
3421 (P) The internal routine used to clear a typeglob's entries tried
3422 repeatedly, but each time something re-created entries in the glob. Most
3423 likely the glob contains an object with a reference back to the glob and a
3424 destructor that adds a new object to the glob.
3426 =item panic: hfreeentries failed to free hash
3428 (P) The internal routine used to clear a hash's entries tried repeatedly,
3429 but each time something added more entries to the hash. Most likely the hash
3430 contains an object with a reference back to the hash and a destructor that
3431 adds a new object to the hash.
3433 =item panic: INTERPCASEMOD
3435 (P) The lexer got into a bad state at a case modifier.
3437 =item panic: INTERPCONCAT
3439 (P) The lexer got into a bad state parsing a string with brackets.
3441 =item panic: kid popen errno read
3443 (F) forked child returned an incomprehensible message about its errno.
3447 (P) We popped the context stack to a block context, and then discovered
3448 it wasn't a block context.
3450 =item panic: leave_scope clearsv
3452 (P) A writable lexical variable became read-only somehow within the
3455 =item panic: leave_scope inconsistency
3457 (P) The savestack probably got out of sync. At least, there was an
3458 invalid enum on the top of it.
3460 =item panic: magic_killbackrefs
3462 (P) Failed an internal consistency check while trying to reset all weak
3463 references to an object.
3467 (P) Something requested a negative number of bytes of malloc.
3469 =item panic: memory wrap
3471 (P) Something tried to allocate more memory than possible.
3473 =item panic: pad_alloc
3475 (P) The compiler got confused about which scratch pad it was allocating
3476 and freeing temporaries and lexicals from.
3478 =item panic: pad_free curpad
3480 (P) The compiler got confused about which scratch pad it was allocating
3481 and freeing temporaries and lexicals from.
3483 =item panic: pad_free po
3485 (P) An invalid scratch pad offset was detected internally.
3487 =item panic: pad_reset curpad
3489 (P) The compiler got confused about which scratch pad it was allocating
3490 and freeing temporaries and lexicals from.
3492 =item panic: pad_sv po
3494 (P) An invalid scratch pad offset was detected internally.
3496 =item panic: pad_swipe curpad
3498 (P) The compiler got confused about which scratch pad it was allocating
3499 and freeing temporaries and lexicals from.
3501 =item panic: pad_swipe po
3503 (P) An invalid scratch pad offset was detected internally.
3505 =item panic: pp_iter
3507 (P) The foreach iterator got called in a non-loop context frame.
3509 =item panic: pp_match%s
3511 (P) The internal pp_match() routine was called with invalid operational
3514 =item panic: pp_split
3516 (P) Something terrible went wrong in setting up for the split.
3518 =item panic: realloc
3520 (P) Something requested a negative number of bytes of realloc.
3522 =item panic: restartop
3524 (P) Some internal routine requested a goto (or something like it), and
3525 didn't supply the destination.
3529 (P) We popped the context stack to a subroutine or eval context, and
3530 then discovered it wasn't a subroutine or eval context.
3532 =item panic: scan_num
3534 (P) scan_num() got called on something that wasn't a number.
3536 =item panic: sv_chop %s
3538 (P) The sv_chop() routine was passed a position that is not within the
3539 scalar's string buffer.
3541 =item panic: sv_insert
3543 (P) The sv_insert() routine was told to remove more string than there
3546 =item panic: top_env
3548 (P) The compiler attempted to do a goto, or something weird like that.
3550 =item panic: unimplemented op %s (#%d) called
3552 (P) The compiler is screwed up and attempted to use an op that isn't
3553 permitted at run time.
3555 =item panic: utf16_to_utf8: odd bytelen
3557 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
3558 to even) byte length.
3560 =item panic: utf16_to_utf8_reversed: odd bytelen
3562 (P) Something tried to call utf16_to_utf8_reversed with an odd (as opposed
3563 to even) byte length.
3567 (P) The lexer got into a bad state while processing a case modifier.
3569 =item Parsing code internal error (%s)
3571 (F) Parsing code supplied by an extension violated the parser's API in
3574 =item Pattern subroutine nesting without pos change exceeded limit in regex; marked by <-- HERE in m/%s/
3576 (F) You used a pattern that uses too many nested subpattern calls without
3577 consuming any text. Restructure the pattern so text is consumed before the
3578 nesting limit is exceeded.
3580 The <-- HERE shows in the regular expression about where the problem was
3583 =item Parentheses missing around "%s" list
3585 (W parenthesis) You said something like
3591 my ($foo, $bar) = @_;
3593 Remember that "my", "our", "local" and "state" bind tighter than comma.
3595 =item C<-p> destination: %s
3597 (F) An error occurred during the implicit output invoked by the C<-p>
3598 command-line switch. (This output goes to STDOUT unless you've
3599 redirected it with select().)
3601 =item (perhaps you forgot to load "%s"?)
3603 (F) This is an educated guess made in conjunction with the message
3604 "Can't locate object method \"%s\" via package \"%s\"". It often means
3605 that a method requires a package that has not been loaded.
3607 =item Perl_my_%s() not available
3609 (F) Your platform has very uncommon byte-order and integer size,
3610 so it was not possible to set up some or all fixed-width byte-order
3611 conversion functions. This is only a problem when you're using the
3612 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
3614 =item Perl %s required--this is only version %s, stopped
3616 (F) The module in question uses features of a version of Perl more
3617 recent than the currently running version. How long has it been since
3618 you upgraded, anyway? See L<perlfunc/require>.
3620 =item PERL_SH_DIR too long
3622 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
3623 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
3625 =item PERL_SIGNALS illegal: "%s"
3627 See L<perlrun/PERL_SIGNALS> for legal values.
3629 =item perl: warning: Setting locale failed.
3631 (S) The whole warning message will look something like:
3633 perl: warning: Setting locale failed.
3634 perl: warning: Please check that your locale settings:
3637 are supported and installed on your system.
3638 perl: warning: Falling back to the standard locale ("C").
3640 Exactly what were the failed locale settings varies. In the above the
3641 settings were that the LC_ALL was "En_US" and the LANG had no value.
3642 This error means that Perl detected that you and/or your operating
3643 system supplier and/or system administrator have set up the so-called
3644 locale system but Perl could not use those settings. This was not
3645 dead serious, fortunately: there is a "default locale" called "C" that
3646 Perl can and will use, and the script will be run. Before you really
3647 fix the problem, however, you will get the same error message each
3648 time you run Perl. How to really fix the problem can be found in
3649 L<perllocale> section B<LOCALE PROBLEMS>.
3651 =item pid %x not a child
3653 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
3654 process which isn't a subprocess of the current process. While this is
3655 fine from VMS' perspective, it's probably not what you intended.
3657 =item 'P' must have an explicit size in unpack
3659 (F) The unpack format P must have an explicit size, not "*".
3661 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
3663 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
3664 shows in the regular expression about where the problem was discovered.
3665 Note that the POSIX character classes do B<not> have the C<is> prefix
3666 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
3667 not C<isprint>. See L<perlre>.
3669 =item POSIX getpgrp can't take an argument
3671 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
3672 the BSD version, which takes a pid.
3674 =item POSIX syntax [%s] belongs inside character classes in regex; marked by <-- HERE in m/%s/
3676 (W regexp) The character class constructs [: :], [= =], and [. .] go
3677 I<inside> character classes, the [] are part of the construct, for example:
3678 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
3679 implemented; they are simply placeholders for future extensions and will
3680 cause fatal errors. The <-- HERE shows in the regular expression about
3681 where the problem was discovered. See L<perlre>.
3683 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3685 (F regexp) Within regular expression character classes ([]) the syntax
3686 beginning with "[." and ending with ".]" is reserved for future extensions.
3687 If you need to represent those character sequences inside a regular
3688 expression character class, just quote the square brackets with the
3689 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
3690 about where the problem was discovered. See L<perlre>.
3692 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3694 (F) Within regular expression character classes ([]) the syntax beginning
3695 with "[=" and ending with "=]" is reserved for future extensions. If you
3696 need to represent those character sequences inside a regular expression
3697 character class, just quote the square brackets with the backslash: "\[="
3698 and "=\]". The <-- HERE shows in the regular expression about where the
3699 problem was discovered. See L<perlre>.
3701 =item Possible attempt to put comments in qw() list
3703 (W qw) qw() lists contain items separated by whitespace; as with literal
3704 strings, comment characters are not ignored, but are instead treated as
3705 literal data. (You may have used different delimiters than the
3706 parentheses shown here; braces are also frequently used.)
3708 You probably wrote something like this:
3715 when you should have written this:
3722 If you really want comments, build your list the
3723 old-fashioned way, with quotes and commas:
3727 'b', # another comment
3730 =item Possible attempt to separate words with commas
3732 (W qw) qw() lists contain items separated by whitespace; therefore
3733 commas aren't needed to separate the items. (You may have used
3734 different delimiters than the parentheses shown here; braces are also
3737 You probably wrote something like this:
3741 which puts literal commas into some of the list items. Write it without
3742 commas if you don't want them to appear in your data:
3746 =item Possible memory corruption: %s overflowed 3rd argument
3748 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
3749 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
3750 end of the buffer just in case. This sentinel byte got clobbered, and
3751 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
3753 =item Possible precedence problem on bitwise %c operator
3755 (W precedence) Your program uses a bitwise logical operator in conjunction
3756 with a numeric comparison operator, like this :
3758 if ($x & $y == 0) { ... }
3760 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
3761 higher precedence of C<==>. This is probably not what you want. (If you
3762 really meant to write this, disable the warning, or, better, put the
3763 parentheses explicitly and write C<$x & ($y == 0)>).
3765 =item Possible unintended interpolation of $\ in regex
3767 (W ambiguous) You said something like C<m/$\/> in a regex.
3768 The regex C<m/foo$\s+bar/m> translates to: match the word 'foo', the output
3769 record separator (see L<perlvar/$\>) and the letter 's' (one time or more)
3770 followed by the word 'bar'.
3772 If this is what you intended then you can silence the warning by using
3773 C<m/${\}/> (for example: C<m/foo${\}s+bar/>).
3775 If instead you intended to match the word 'foo' at the end of the line
3776 followed by whitespace and the word 'bar' on the next line then you can use
3777 C<m/$(?)\/> (for example: C<m/foo$(?)\s+bar/>).
3779 =item Possible unintended interpolation of %s in string
3781 (W ambiguous) You said something like `@foo' in a double-quoted string
3782 but there was no array C<@foo> in scope at the time. If you wanted a
3783 literal @foo, then write it as \@foo; otherwise find out what happened
3784 to the array you apparently lost track of.
3786 =item Precedence problem: open %s should be open(%s)
3788 (S precedence) The old irregular construct
3792 is now misinterpreted as
3796 because of the strict regularization of Perl 5's grammar into unary and
3797 list operators. (The old open was a little of both.) You must put
3798 parentheses around the filehandle, or use the new "or" operator instead
3801 =item Premature end of script headers
3805 =item printf() on closed filehandle %s
3807 (W closed) The filehandle you're writing to got itself closed sometime
3808 before now. Check your control flow.
3810 =item print() on closed filehandle %s
3812 (W closed) The filehandle you're printing on got itself closed sometime
3813 before now. Check your control flow.
3815 =item Process terminated by SIG%s
3817 (W) This is a standard message issued by OS/2 applications, while *nix
3818 applications die in silence. It is considered a feature of the OS/2
3819 port. One can easily disable this by appropriate sighandlers, see
3820 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
3823 =item Prototype after '%c' for %s : %s
3825 (W illegalproto) A character follows % or @ in a prototype. This is useless,
3826 since % and @ gobble the rest of the subroutine arguments.
3828 =item Prototype mismatch: %s vs %s
3830 (S prototype) The subroutine being declared or defined had previously been
3831 declared or defined with a different function prototype.
3833 =item Prototype not terminated
3835 (F) You've omitted the closing parenthesis in a function prototype
3838 =item \p{} uses Unicode rules, not locale rules
3840 (W) You compiled a regular expression that contained a Unicode property
3841 match (C<\p> or C<\P>), but the regular expression is also being told to
3842 use the run-time locale, not Unicode. Instead, use a POSIX character
3843 class, which should know about the locale's rules.
3844 (See L<perlrecharclass/POSIX Character Classes>.)
3846 Even if the run-time locale is ISO 8859-1 (Latin1), which is a subset of
3847 Unicode, some properties will give results that are not valid for that
3850 Here are a couple of examples to help you see what's going on. If the
3851 locale is ISO 8859-7, the character at code point 0xD7 is the "GREEK
3852 CAPITAL LETTER CHI". But in Unicode that code point means the
3853 "MULTIPLICATION SIGN" instead, and C<\p> always uses the Unicode
3854 meaning. That means that C<\p{Alpha}> won't match, but C<[[:alpha:]]>
3855 should. Only in the Latin1 locale are all the characters in the same
3856 positions as they are in Unicode. But, even here, some properties give
3857 incorrect results. An example is C<\p{Changes_When_Uppercased}> which
3858 is true for "LATIN SMALL LETTER Y WITH DIAERESIS", but since the upper
3859 case of that character is not in Latin1, in that locale it doesn't
3860 change when upper cased.
3862 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
3864 (F) You started a regular expression with a quantifier. Backslash it if you
3865 meant it literally. The <-- HERE shows in the regular expression about
3866 where the problem was discovered. See L<perlre>.
3868 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
3870 (F) There is currently a limit to the size of the min and max values of the
3871 {min,max} construct. The <-- HERE shows in the regular expression about where
3872 the problem was discovered. See L<perlre>.
3874 =item Quantifier unexpected on zero-length expression; marked by <-- HERE in m/%s/
3876 (W regexp) You applied a regular expression quantifier in a place where
3877 it makes no sense, such as on a zero-width assertion. Try putting the
3878 quantifier inside the assertion instead. For example, the way to match
3879 "abc" provided that it is followed by three repetitions of "xyz" is
3880 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
3882 The <-- HERE shows in the regular expression about where the problem was
3885 =item Range iterator outside integer range
3887 (F) One (or both) of the numeric arguments to the range operator ".."
3888 are outside the range which can be represented by integers internally.
3889 One possible workaround is to force Perl to use magical string increment
3890 by prepending "0" to your numbers.
3892 =item readdir() attempted on invalid dirhandle %s
3894 (W io) The dirhandle you're reading from is either closed or not really
3895 a dirhandle. Check your control flow.
3897 =item readline() on closed filehandle %s
3899 (W closed) The filehandle you're reading from got itself closed sometime
3900 before now. Check your control flow.
3902 =item read() on closed filehandle %s
3904 (W closed) You tried to read from a closed filehandle.
3906 =item read() on unopened filehandle %s
3908 (W unopened) You tried to read from a filehandle that was never opened.
3910 =item Reallocation too large: %x
3912 (F) You can't allocate more than 64K on an MS-DOS machine.
3914 =item realloc() of freed memory ignored
3916 (S malloc) An internal routine called realloc() on something that had
3919 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3921 (F debugging) You can't use the B<-D> option unless the code to produce
3922 the desired output is compiled into Perl, which entails some overhead,
3923 which is why it's currently left out of your copy.
3925 =item Recursive inheritance detected in package '%s'
3927 (F) While calculating the method resolution order (MRO) of a package, Perl
3928 believes it found an infinite loop in the C<@ISA> hierarchy. This is a
3929 crude check that bails out after 100 levels of C<@ISA> depth.
3931 =item Reference found where even-sized list expected
3933 (W misc) You gave a single reference where Perl was expecting a list
3934 with an even number of elements (for assignment to a hash). This usually
3935 means that you used the anon hash constructor when you meant to use
3936 parens. In any case, a hash requires key/value B<pairs>.
3938 %hash = { one => 1, two => 2, }; # WRONG
3939 %hash = [ qw/ an anon array / ]; # WRONG
3940 %hash = ( one => 1, two => 2, ); # right
3941 %hash = qw( one 1 two 2 ); # also fine
3943 =item Reference is already weak
3945 (W misc) You have attempted to weaken a reference that is already weak.
3946 Doing so has no effect.
3948 =item Reference miscount in sv_replace()
3950 (W internal) The internal sv_replace() function was handed a new SV with
3951 a reference count other than 1.
3953 =item Reference to invalid group 0
3955 (F) You used C<\g0> or similar in a regular expression. You may refer to
3956 capturing parentheses only with strictly positive integers (normal
3957 backreferences) or with strictly negative integers (relative
3958 backreferences). Using 0 does not make sense.
3960 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
3962 (F) You used something like C<\7> in your regular expression, but there are
3963 not at least seven sets of capturing parentheses in the expression. If
3964 you wanted to have the character with ordinal 7 inserted into the regular
3965 expression, prepend zeroes to make it three digits long: C<\007>
3967 The <-- HERE shows in the regular expression about where the problem was
3970 =item Reference to nonexistent named group in regex; marked by <-- HERE in m/%s/
3972 (F) You used something like C<\k'NAME'> or C<< \k<NAME> >> in your regular
3973 expression, but there is no corresponding named capturing parentheses
3974 such as C<(?'NAME'...)> or C<< (?<NAME>...) >>. Check if the name has been
3975 spelled correctly both in the backreference and the declaration.
3977 The <-- HERE shows in the regular expression about where the problem was
3980 =item Reference to nonexistent or unclosed group in regex; marked by <-- HERE in m/%s/
3982 (F) You used something like C<\g{-7}> in your regular expression, but there
3983 are not at least seven sets of closed capturing parentheses in the
3984 expression before where the C<\g{-7}> was located.
3986 The <-- HERE shows in the regular expression about where the problem was
3989 =item regexp memory corruption
3991 (P) The regular expression engine got confused by what the regular
3992 expression compiler gave it.
3994 =item Regexp out of space
3996 (P) A "can't happen" error, because safemalloc() should have caught it
3999 =item Repeated format line will never terminate (~~ and @# incompatible)
4001 (F) Your format contains the ~~ repeat-until-blank sequence and a
4002 numeric field that will never go blank so that the repetition never
4003 terminates. You might use ^# instead. See L<perlform>.
4005 =item Replacement list is longer than search list
4007 (W misc) You have used a replacement list that is longer than the
4008 search list. So the additional elements in the replacement list
4011 =item Reversed %s= operator
4013 (W syntax) You wrote your assignment operator backwards. The = must
4014 always come last, to avoid ambiguity with subsequent unary operators.
4016 =item rewinddir() attempted on invalid dirhandle %s
4018 (W io) The dirhandle you tried to do a rewinddir() on is either closed or not
4019 really a dirhandle. Check your control flow.
4021 =item Scalars leaked: %d
4023 (P) Something went wrong in Perl's internal bookkeeping of scalars:
4024 not all scalar variables were deallocated by the time Perl exited.
4025 What this usually indicates is a memory leak, which is of course bad,
4026 especially if the Perl program is intended to be long-running.
4028 =item Scalar value @%s[%s] better written as $%s[%s]
4030 (W syntax) You've used an array slice (indicated by @) to select a
4031 single element of an array. Generally it's better to ask for a scalar
4032 value (indicated by $). The difference is that C<$foo[&bar]> always
4033 behaves like a scalar, both when assigning to it and when evaluating its
4034 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
4035 and provides a list context to its subscript, which can do weird things
4036 if you're expecting only one subscript.
4038 On the other hand, if you were actually hoping to treat the array
4039 element as a list, you need to look into how references work, because
4040 Perl will not magically convert between scalars and lists for you. See
4043 =item Scalar value @%s{%s} better written as $%s{%s}
4045 (W syntax) You've used a hash slice (indicated by @) to select a single
4046 element of a hash. Generally it's better to ask for a scalar value
4047 (indicated by $). The difference is that C<$foo{&bar}> always behaves
4048 like a scalar, both when assigning to it and when evaluating its
4049 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
4050 and provides a list context to its subscript, which can do weird things
4051 if you're expecting only one subscript.
4053 On the other hand, if you were actually hoping to treat the hash element
4054 as a list, you need to look into how references work, because Perl will
4055 not magically convert between scalars and lists for you. See
4058 =item Search pattern not terminated
4060 (F) The lexer couldn't find the final delimiter of a // or m{}
4061 construct. Remember that bracketing delimiters count nesting level.
4062 Missing the leading C<$> from a variable C<$m> may cause this error.
4064 Note that since Perl 5.9.0 a // can also be the I<defined-or>
4065 construct, not just the empty search pattern. Therefore code written
4066 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
4067 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
4069 =item Search pattern not terminated or ternary operator parsed as search pattern
4071 (F) The lexer couldn't find the final delimiter of a C<?PATTERN?>
4074 The question mark is also used as part of the ternary operator (as in
4075 C<foo ? 0 : 1>) leading to some ambiguous constructions being wrongly
4076 parsed. One way to disambiguate the parsing is to put parentheses around
4077 the conditional expression, i.e. C<(foo) ? 0 : 1>.
4079 =item seekdir() attempted on invalid dirhandle %s
4081 (W io) The dirhandle you are doing a seekdir() on is either closed or not
4082 really a dirhandle. Check your control flow.
4084 =item %sseek() on unopened filehandle
4086 (W unopened) You tried to use the seek() or sysseek() function on a
4087 filehandle that was either never opened or has since been closed.
4089 =item select not implemented
4091 (F) This machine doesn't implement the select() system call.
4093 =item Self-ties of arrays and hashes are not supported
4095 (F) Self-ties are of arrays and hashes are not supported in
4096 the current implementation.
4098 =item Semicolon seems to be missing
4100 (W semicolon) A nearby syntax error was probably caused by a missing
4101 semicolon, or possibly some other missing operator, such as a comma.
4103 =item semi-panic: attempt to dup freed string
4105 (S internal) The internal newSVsv() routine was called to duplicate a
4106 scalar that had previously been marked as free.
4108 =item sem%s not implemented
4110 (F) You don't have System V semaphore IPC on your system.
4112 =item send() on closed socket %s
4114 (W closed) The socket you're sending to got itself closed sometime
4115 before now. Check your control flow.
4117 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
4119 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
4120 shows in the regular expression about where the problem was discovered. See
4123 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
4125 (F) A proposed regular expression extension has the character reserved but
4126 has not yet been written. The <-- HERE shows in the regular expression about
4127 where the problem was discovered. See L<perlre>.
4129 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
4131 (F) You used a regular expression extension that doesn't make sense. The
4132 <-- HERE shows in the regular expression about where the problem was
4133 discovered. This happens when using the C<(?^...)> construct to tell
4134 Perl to use the default regular expression modifiers, and you
4135 redundantly specify a default modifier; or having a modifier that can't
4136 be turned off (such as C<"p"> or C<"l">) after a minus; or specifying
4137 more than one of the C<"d">, C<"l">, or C<"u"> modifiers. For other
4138 causes, see L<perlre>.
4140 =item Sequence \%s... not terminated in regex; marked by <-- HERE in m/%s/
4142 (F) The regular expression expects a mandatory argument following the escape
4143 sequence and this has been omitted or incorrectly written.
4145 =item Sequence (?#... not terminated in regex; marked by <-- HERE in m/%s/
4147 (F) A regular expression comment must be terminated by a closing
4148 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
4149 the regular expression about where the problem was discovered. See
4152 =item Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/%s/
4154 (F) If the contents of a (?{...}) clause contain braces, they must balance
4155 for Perl to detect the end of the clause properly. The <-- HERE shows in
4156 the regular expression about where the problem was discovered. See
4159 =item "500 Server error"
4165 (A) This is the error message generally seen in a browser window when trying
4166 to run a CGI program (including SSI) over the web. The actual error text
4167 varies widely from server to server. The most frequently-seen variants
4168 are "500 Server error", "Method (something) not permitted", "Document
4169 contains no data", "Premature end of script headers", and "Did not
4170 produce a valid header".
4172 B<This is a CGI error, not a Perl error>.
4174 You need to make sure your script is executable, is accessible by the
4175 user CGI is running the script under (which is probably not the user
4176 account you tested it under), does not rely on any environment variables
4177 (like PATH) from the user it isn't running under, and isn't in a
4178 location where the CGI server can't find it, basically, more or less.
4179 Please see the following for more information:
4181 http://www.perl.org/CGI_MetaFAQ.html
4182 http://www.htmlhelp.org/faq/cgifaq.html
4183 http://www.w3.org/Security/Faq/
4185 You should also look at L<perlfaq9>.
4187 =item setegid() not implemented
4189 (F) You tried to assign to C<$)>, and your operating system doesn't
4190 support the setegid() system call (or equivalent), or at least Configure
4193 =item seteuid() not implemented
4195 (F) You tried to assign to C<< $> >>, and your operating system doesn't
4196 support the seteuid() system call (or equivalent), or at least Configure
4199 =item setpgrp can't take arguments
4201 (F) Your system has the setpgrp() from BSD 4.2, which takes no
4202 arguments, unlike POSIX setpgid(), which takes a process ID and process
4205 =item setrgid() not implemented
4207 (F) You tried to assign to C<$(>, and your operating system doesn't
4208 support the setrgid() system call (or equivalent), or at least Configure
4211 =item setruid() not implemented
4213 (F) You tried to assign to C<$<>, and your operating system doesn't
4214 support the setruid() system call (or equivalent), or at least Configure
4217 =item setsockopt() on closed socket %s
4219 (W closed) You tried to set a socket option on a closed socket. Did you
4220 forget to check the return value of your socket() call? See
4221 L<perlfunc/setsockopt>.
4223 =item Setuid/gid script is writable by world
4225 (F) The setuid emulator won't run a script that is writable by the
4226 world, because the world might have written on it already.
4228 =item Setuid script not plain file
4230 (F) The setuid emulator won't run a script that isn't read from a file,
4231 but from a socket, a pipe or another device.
4233 =item shm%s not implemented
4235 (F) You don't have System V shared memory IPC on your system.
4237 =item !=~ should be !~
4239 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
4240 interpreted as the != (numeric not equal) and ~ (1's complement)
4241 operators: probably not what you intended.
4243 =item <> should be quotes
4245 (F) You wrote C<< require <file> >> when you should have written
4248 =item /%s/ should probably be written as "%s"
4250 (W syntax) You have used a pattern where Perl expected to find a string,
4251 as in the first argument to C<join>. Perl will treat the true or false
4252 result of matching the pattern against $_ as the string, which is
4253 probably not what you had in mind.
4255 =item shutdown() on closed socket %s
4257 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
4260 =item SIG%s handler "%s" not defined
4262 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
4263 Perhaps you put it into the wrong package?
4265 =item Smart matching a non-overloaded object breaks encapsulation
4267 (F) You should not use the C<~~> operator on an object that does not
4268 overload it: Perl refuses to use the object's underlying structure for
4271 =item sort is now a reserved word
4273 (F) An ancient error message that almost nobody ever runs into anymore.
4274 But before sort was a keyword, people sometimes used it as a filehandle.
4276 =item Sort subroutine didn't return single value
4278 (F) A sort comparison subroutine may not return a list value with more
4279 or less than one element. See L<perlfunc/sort>.
4281 =item splice() offset past end of array
4283 (W misc) You attempted to specify an offset that was past the end of
4284 the array passed to splice(). Splicing will instead commence at the end
4285 of the array, rather than past it. If this isn't what you want, try
4286 explicitly pre-extending the array by assigning $#array = $offset. See
4291 (P) The split was looping infinitely. (Obviously, a split shouldn't
4292 iterate more times than there are characters of input, which is what
4293 happened.) See L<perlfunc/split>.
4295 =item Statement unlikely to be reached
4297 (W exec) You did an exec() with some statement after it other than a
4298 die(). This is almost always an error, because exec() never returns
4299 unless there was a failure. You probably wanted to use system()
4300 instead, which does return. To suppress this warning, put the exec() in
4303 =item "state" variable %s can't be in a package
4305 (F) Lexically scoped variables aren't in a package, so it doesn't make
4306 sense to try to declare one with a package qualifier on the front. Use
4307 local() if you want to localize a package variable.
4309 =item stat() on unopened filehandle %s
4311 (W unopened) You tried to use the stat() function on a filehandle that
4312 was either never opened or has since been closed.
4314 =item Stub found while resolving method "%s" overloading "%s" in package "%s"
4316 (P) Overloading resolution over @ISA tree may be broken by importation
4317 stubs. Stubs should never be implicitly created, but explicit calls to
4318 C<can> may break this.
4320 =item Subroutine %s redefined
4322 (W redefine) You redefined a subroutine. To suppress this warning, say
4325 no warnings 'redefine';
4326 eval "sub name { ... }";
4329 =item Substitution loop
4331 (P) The substitution was looping infinitely. (Obviously, a substitution
4332 shouldn't iterate more times than there are characters of input, which
4333 is what happened.) See the discussion of substitution in
4334 L<perlop/"Regexp Quote-Like Operators">.
4336 =item Substitution pattern not terminated
4338 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
4339 construct. Remember that bracketing delimiters count nesting level.
4340 Missing the leading C<$> from variable C<$s> may cause this error.
4342 =item Substitution replacement not terminated
4344 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
4345 construct. Remember that bracketing delimiters count nesting level.
4346 Missing the leading C<$> from variable C<$s> may cause this error.
4348 =item substr outside of string
4350 (W substr),(F) You tried to reference a substr() that pointed outside of
4351 a string. That is, the absolute value of the offset was larger than the
4352 length of the string. See L<perlfunc/substr>. This warning is fatal if
4353 substr is used in an lvalue context (as the left hand side of an
4354 assignment or as a subroutine argument for example).
4356 =item sv_upgrade from type %d down to type %d
4358 (P) Perl tried to force the upgrade an SV to a type which was actually
4359 inferior to its current type.
4361 =item Switch (?(condition)... contains too many branches in regex; marked by <-- HERE in m/%s/
4363 (F) A (?(condition)if-clause|else-clause) construct can have at most two
4364 branches (the if-clause and the else-clause). If you want one or both to
4365 contain alternation, such as using C<this|that|other>, enclose it in
4366 clustering parentheses:
4368 (?(condition)(?:this|that|other)|else-clause)
4370 The <-- HERE shows in the regular expression about where the problem was
4371 discovered. See L<perlre>.
4373 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
4375 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
4376 number, it can be only a number. The <-- HERE shows in the regular expression
4377 about where the problem was discovered. See L<perlre>.
4379 =item switching effective %s is not implemented
4381 (F) While under the C<use filetest> pragma, we cannot switch the real
4382 and effective uids or gids.
4386 (F) The final summary message when a C<perl -c> succeeds.
4390 (F) Probably means you had a syntax error. Common reasons include:
4392 A keyword is misspelled.
4393 A semicolon is missing.
4395 An opening or closing parenthesis is missing.
4396 An opening or closing brace is missing.
4397 A closing quote is missing.
4399 Often there will be another error message associated with the syntax
4400 error giving more information. (Sometimes it helps to turn on B<-w>.)
4401 The error message itself often tells you where it was in the line when
4402 it decided to give up. Sometimes the actual error is several tokens
4403 before this, because Perl is good at understanding random input.
4404 Occasionally the line number may be misleading, and once in a blue moon
4405 the only way to figure out what's triggering the error is to call
4406 C<perl -c> repeatedly, chopping away half the program each time to see
4407 if the error went away. Sort of the cybernetic version of S<20
4410 =item syntax error at line %d: `%s' unexpected
4412 (A) You've accidentally run your script through the Bourne shell instead
4413 of Perl. Check the #! line, or manually feed your script into Perl
4416 =item syntax error in file %s at line %d, next 2 tokens "%s"
4418 (F) This error is likely to occur if you run a perl5 script through
4419 a perl4 interpreter, especially if the next 2 tokens are "use strict"
4420 or "my $var" or "our $var".
4422 =item sysread() on closed filehandle %s
4424 (W closed) You tried to read from a closed filehandle.
4426 =item sysread() on unopened filehandle %s
4428 (W unopened) You tried to read from a filehandle that was never opened.
4430 =item System V %s is not implemented on this machine
4432 (F) You tried to do something with a function beginning with "sem",
4433 "shm", or "msg" but that System V IPC is not implemented in your
4434 machine. In some machines the functionality can exist but be
4435 unconfigured. Consult your system support.
4437 =item syswrite() on closed filehandle %s
4439 (W closed) The filehandle you're writing to got itself closed sometime
4440 before now. Check your control flow.
4442 =item C<-T> and C<-B> not implemented on filehandles
4444 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
4445 know about your kind of stdio. You'll have to use a filename instead.
4447 =item Target of goto is too deeply nested
4449 (F) You tried to use C<goto> to reach a label that was too deeply nested
4450 for Perl to reach. Perl is doing you a favor by refusing.
4452 =item tell() on unopened filehandle
4454 (W unopened) You tried to use the tell() function on a filehandle that
4455 was either never opened or has since been closed.
4457 =item telldir() attempted on invalid dirhandle %s
4459 (W io) The dirhandle you tried to telldir() is either closed or not really
4460 a dirhandle. Check your control flow.
4462 =item That use of $[ is unsupported
4464 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
4465 as a compiler directive. You may say only one of
4474 This is to prevent the problem of one module changing the array base out
4475 from under another module inadvertently. See L<perlvar/$[>.
4477 =item The crypt() function is unimplemented due to excessive paranoia
4479 (F) Configure couldn't find the crypt() function on your machine,
4480 probably because your vendor didn't supply it, probably because they
4481 think the U.S. Government thinks it's a secret, or at least that they
4482 will continue to pretend that it is. And if you quote me on that, I
4485 =item The %s function is unimplemented
4487 (F) The function indicated isn't implemented on this architecture, according
4488 to the probings of Configure.
4490 =item The stat preceding %s wasn't an lstat
4492 (F) It makes no sense to test the current stat buffer for symbolic
4493 linkhood if the last stat that wrote to the stat buffer already went
4494 past the symlink to get to the real file. Use an actual filename
4497 =item The 'unique' attribute may only be applied to 'our' variables
4499 (F) This attribute was never supported on C<my> or C<sub> declarations.
4501 =item This Perl can't reset CRTL environ elements (%s)
4503 =item This Perl can't set CRTL environ elements (%s=%s)
4505 (W internal) Warnings peculiar to VMS. You tried to change or delete an
4506 element of the CRTL's internal environ array, but your copy of Perl
4507 wasn't built with a CRTL that contained the setenv() function. You'll
4508 need to rebuild Perl with a CRTL that does, or redefine
4509 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
4510 target of the change to
4511 %ENV which produced the warning.
4513 =item thread failed to start: %s
4515 (W threads)(S) The entry point function of threads->create() failed for some reason.
4517 =item times not implemented
4519 (F) Your version of the C library apparently doesn't do times(). I
4520 suspect you're not running on Unix.
4522 =item "-T" is on the #! line, it must also be used on the command line
4524 (X) The #! line (or local equivalent) in a Perl script contains the
4525 B<-T> option (or the B<-t> option), but Perl was not invoked with B<-T> in its command line.
4526 This is an error because, by the time Perl discovers a B<-T> in a
4527 script, it's too late to properly taint everything from the environment.
4530 If the Perl script is being executed as a command using the #!
4531 mechanism (or its local equivalent), this error can usually be fixed by
4532 editing the #! line so that the B<-%c> option is a part of Perl's first
4533 argument: e.g. change C<perl -n -%c> to C<perl -%c -n>.
4535 If the Perl script is being executed as C<perl scriptname>, then the
4536 B<-%c> option must appear on the command line: C<perl -%c scriptname>.
4538 =item To%s: illegal mapping '%s'
4540 (F) You tried to define a customized To-mapping for lc(), lcfirst,
4541 uc(), or ucfirst() (or their string-inlined versions), but you
4542 specified an illegal mapping.
4543 See L<perlunicode/"User-Defined Character Properties">.
4545 =item Too deeply nested ()-groups
4547 (F) Your template contains ()-groups with a ridiculously deep nesting level.
4549 =item Too few args to syscall
4551 (F) There has to be at least one argument to syscall() to specify the
4552 system call to call, silly dilly.
4554 =item Too late for "-%s" option
4556 (X) The #! line (or local equivalent) in a Perl script contains the
4557 B<-M>, B<-m> or B<-C> option.
4559 In the case of B<-M> and B<-m>, this is an error because those options are
4560 not intended for use inside scripts. Use the C<use> pragma instead.
4562 The B<-C> option only works if it is specified on the command line as well
4563 (with the same sequence of letters or numbers following). Either specify
4564 this option on the command line, or, if your system supports it, make your
4565 script executable and run it directly instead of passing it to perl.
4567 =item Too late to run %s block
4569 (W void) A CHECK or INIT block is being defined during run time proper,
4570 when the opportunity to run them has already passed. Perhaps you are
4571 loading a file with C<require> or C<do> when you should be using C<use>
4572 instead. Or perhaps you should put the C<require> or C<do> inside a
4575 =item Too many args to syscall
4577 (F) Perl supports a maximum of only 14 args to syscall().
4579 =item Too many arguments for %s
4581 (F) The function requires fewer arguments than you specified.
4585 (A) You've accidentally run your script through B<csh> instead of Perl.
4586 Check the #! line, or manually feed your script into Perl yourself.
4590 (A) You've accidentally run your script through B<csh> instead of Perl.
4591 Check the #! line, or manually feed your script into Perl yourself.
4593 =item Trailing \ in regex m/%s/
4595 (F) The regular expression ends with an unbackslashed backslash.
4596 Backslash it. See L<perlre>.
4598 =item Transliteration pattern not terminated
4600 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
4601 or y/// or y[][] construct. Missing the leading C<$> from variables
4602 C<$tr> or C<$y> may cause this error.
4604 =item Transliteration replacement not terminated
4606 (F) The lexer couldn't find the final delimiter of a tr///, tr[][],
4607 y/// or y[][] construct.
4609 =item '%s' trapped by operation mask
4611 (F) You tried to use an operator from a Safe compartment in which it's
4612 disallowed. See L<Safe>.
4614 =item truncate not implemented
4616 (F) Your machine doesn't implement a file truncation mechanism that
4617 Configure knows about.
4619 =item Type of arg %d to %s must be %s (not %s)
4621 (F) This function requires the argument in that position to be of a
4622 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
4623 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
4624 {EXPR} forms as an explicit dereference. See L<perlref>.
4626 =item Type of argument to %s must be hashref or arrayref
4628 (F) You called C<keys>, C<values> or C<each> with an argument that was
4629 expected to be a reference to a hash or a reference to an array.
4631 =item umask not implemented
4633 (F) Your machine doesn't implement the umask function and you tried to
4634 use it to restrict permissions for yourself (EXPR & 0700).
4636 =item Unable to create sub named "%s"
4638 (F) You attempted to create or access a subroutine with an illegal name.
4640 =item Unbalanced context: %d more PUSHes than POPs
4642 (W internal) The exit code detected an internal inconsistency in how
4643 many execution contexts were entered and left.
4645 =item Unbalanced saves: %d more saves than restores
4647 (W internal) The exit code detected an internal inconsistency in how
4648 many values were temporarily localized.
4650 =item Unbalanced scopes: %d more ENTERs than LEAVEs
4652 (W internal) The exit code detected an internal inconsistency in how
4653 many blocks were entered and left.
4655 =item Unbalanced tmps: %d more allocs than frees
4657 (W internal) The exit code detected an internal inconsistency in how
4658 many mortal scalars were allocated and freed.
4660 =item Undefined format "%s" called
4662 (F) The format indicated doesn't seem to exist. Perhaps it's really in
4663 another package? See L<perlform>.
4665 =item Undefined sort subroutine "%s" called
4667 (F) The sort comparison routine specified doesn't seem to exist.
4668 Perhaps it's in a different package? See L<perlfunc/sort>.
4670 =item Undefined subroutine &%s called
4672 (F) The subroutine indicated hasn't been defined, or if it was, it has
4673 since been undefined.
4675 =item Undefined subroutine called
4677 (F) The anonymous subroutine you're trying to call hasn't been defined,
4678 or if it was, it has since been undefined.
4680 =item Undefined subroutine in sort
4682 (F) The sort comparison routine specified is declared but doesn't seem
4683 to have been defined yet. See L<perlfunc/sort>.
4685 =item Undefined top format "%s" called
4687 (F) The format indicated doesn't seem to exist. Perhaps it's really in
4688 another package? See L<perlform>.
4690 =item Undefined value assigned to typeglob
4692 (W misc) An undefined value was assigned to a typeglob, a la
4693 C<*foo = undef>. This does nothing. It's possible that you really mean
4696 =item %s: Undefined variable
4698 (A) You've accidentally run your script through B<csh> instead of Perl.
4699 Check the #! line, or manually feed your script into Perl yourself.
4701 =item unexec of %s into %s failed!
4703 (F) The unexec() routine failed for some reason. See your local FSF
4704 representative, who probably put it there in the first place.
4706 =item Unicode non-character U+%X is illegal for open interchange
4708 (W utf8) Certain codepoints, such as U+FFFE and U+FFFF, are defined by the
4709 Unicode standard to be non-characters. Those are legal codepoints, but are
4710 reserved for internal use; so, applications shouldn't attempt to exchange
4711 them. If you know what you are doing you can turn
4712 off this warning by C<no warnings 'utf8';>.
4714 =item Unknown BYTEORDER
4716 (F) There are no byte-swapping functions for a machine with this byte
4719 =item Unknown open() mode '%s'
4721 (F) The second argument of 3-argument open() is not among the list
4722 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
4723 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
4725 =item Unknown PerlIO layer "%s"
4727 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
4728 system. (Layers take care of transforming data between external and
4729 internal representations.) Note that some layers, such as C<mmap>,
4730 are not supported in all environments. If your program didn't
4731 explicitly request the failing operation, it may be the result of the
4732 value of the environment variable PERLIO.
4734 =item Unknown process %x sent message to prime_env_iter: %s
4736 (P) An error peculiar to VMS. Perl was reading values for %ENV before
4737 iterating over it, and someone else stuck a message in the stream of
4738 data Perl expected. Someone's very confused, or perhaps trying to
4739 subvert Perl's population of %ENV for nefarious purposes.
4741 =item Unknown "re" subpragma '%s' (known ones are: %s)
4743 (W) You tried to use an unknown subpragma of the "re" pragma.
4745 =item Unknown switch condition (?(%s in regex; marked by <-- HERE in m/%s/
4747 (F) The condition part of a (?(condition)if-clause|else-clause) construct
4748 is not known. The condition may be lookahead or lookbehind (the condition
4749 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
4750 condition is true if the code evaluates to a true value), or a number (the
4751 condition is true if the set of capturing parentheses named by the number
4754 The <-- HERE shows in the regular expression about where the problem was
4755 discovered. See L<perlre>.
4757 =item Unknown Unicode option letter '%c'
4759 (F) You specified an unknown Unicode option. See L<perlrun> documentation
4760 of the C<-C> switch for the list of known options.
4762 =item Unknown Unicode option value %x
4764 (F) You specified an unknown Unicode option. See L<perlrun> documentation
4765 of the C<-C> switch for the list of known options.
4767 =item Unknown warnings category '%s'
4769 (F) An error issued by the C<warnings> pragma. You specified a warnings
4770 category that is unknown to perl at this point.
4772 Note that if you want to enable a warnings category registered by a module
4773 (e.g. C<use warnings 'File::Find'>), you must have imported this module
4775 =item Unknown verb pattern '%s' in regex; marked by <-- HERE in m/%s/
4777 (F) You either made a typo or have incorrectly put a C<*> quantifier
4778 after an open brace in your pattern. Check the pattern and review
4779 L<perlre> for details on legal verb patterns.
4783 =item unmatched [ in regex; marked by <-- HERE in m/%s/
4785 (F) The brackets around a character class must match. If you wish to
4786 include a closing bracket in a character class, backslash it or put it
4787 first. The <-- HERE shows in the regular expression about where the problem
4788 was discovered. See L<perlre>.
4790 =item unmatched ( in regex; marked by <-- HERE in m/%s/
4792 (F) Unbackslashed parentheses must always be balanced in regular
4793 expressions. If you're a vi user, the % key is valuable for finding the
4794 matching parenthesis. The <-- HERE shows in the regular expression about
4795 where the problem was discovered. See L<perlre>.
4797 =item Unmatched right %s bracket
4799 (F) The lexer counted more closing curly or square brackets than opening
4800 ones, so you're probably missing a matching opening bracket. As a
4801 general rule, you'll find the missing one (so to speak) near the place
4802 you were last editing.
4804 =item Unquoted string "%s" may clash with future reserved word
4806 (W reserved) You used a bareword that might someday be claimed as a
4807 reserved word. It's best to put such a word in quotes, or capitalize it
4808 somehow, or insert an underbar into it. You might also declare it as a
4811 =item Unrecognized character %s; marked by <-- HERE after %s near column %d
4813 (F) The Perl parser has no idea what to do with the specified character
4814 in your Perl script (or eval) near the specified column. Perhaps you tried
4815 to run a compressed script, a binary program, or a directory as a Perl program.
4817 =item Unrecognized escape \%c in character class passed through in regex; marked by <-- HERE in m/%s/
4819 (W regexp) You used a backslash-character combination which is not
4820 recognized by Perl inside character classes. The character was
4821 understood literally, but this may change in a future version of Perl.
4822 The <-- HERE shows in the regular expression about where the
4823 escape was discovered.
4825 =item Unrecognized escape \%c passed through
4827 (W misc) You used a backslash-character combination which is not
4828 recognized by Perl. The character was understood literally, but this may
4829 change in a future version of Perl.
4831 =item Unrecognized escape \%s passed through in regex; marked by <-- HERE in m/%s/
4833 (W regexp) You used a backslash-character combination which is not
4834 recognized by Perl. The character(s) were understood literally, but this may
4835 change in a future version of Perl.
4836 The <-- HERE shows in the regular expression about where the
4837 escape was discovered.
4839 =item Unrecognized signal name "%s"
4841 (F) You specified a signal name to the kill() function that was not
4842 recognized. Say C<kill -l> in your shell to see the valid signal names
4845 =item Unrecognized switch: -%s (-h will show valid options)
4847 (F) You specified an illegal option to Perl. Don't do that. (If you
4848 think you didn't do that, check the #! line to see if it's supplying the
4849 bad switch on your behalf.)
4851 =item Unsuccessful %s on filename containing newline
4853 (W newline) A file operation was attempted on a filename, and that
4854 operation failed, PROBABLY because the filename contained a newline,
4855 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
4857 =item Unsupported directory function "%s" called
4859 (F) Your machine doesn't support opendir() and readdir().
4861 =item Unsupported function %s
4863 (F) This machine doesn't implement the indicated function, apparently.
4864 At least, Configure doesn't think so.
4866 =item Unsupported function fork
4868 (F) Your version of executable does not support forking.
4870 Note that under some systems, like OS/2, there may be different flavors
4871 of Perl executables, some of which may support fork, some not. Try
4872 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
4874 =item Unsupported script encoding %s
4876 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
4877 declares it to be in a Unicode encoding that Perl cannot read.
4879 =item Unsupported socket function "%s" called
4881 (F) Your machine doesn't support the Berkeley socket mechanism, or at
4882 least that's what Configure thought.
4884 =item Unterminated attribute list
4886 (F) The lexer found something other than a simple identifier at the
4887 start of an attribute, and it wasn't a semicolon or the start of a
4888 block. Perhaps you terminated the parameter list of the previous
4889 attribute too soon. See L<attributes>.
4891 =item Unterminated attribute parameter in attribute list
4893 (F) The lexer saw an opening (left) parenthesis character while parsing
4894 an attribute list, but the matching closing (right) parenthesis
4895 character was not found. You may need to add (or remove) a backslash
4896 character to get your parentheses to balance. See L<attributes>.
4898 =item Unterminated compressed integer
4900 (F) An argument to unpack("w",...) was incompatible with the BER
4901 compressed integer format and could not be converted to an integer.
4902 See L<perlfunc/pack>.
4904 =item Unterminated verb pattern in regex; marked by <-- HERE in m/%s/
4906 (F) You used a pattern of the form C<(*VERB)> but did not terminate
4907 the pattern with a C<)>. Fix the pattern and retry.
4909 =item Unterminated verb pattern argument in regex; marked by <-- HERE in m/%s/
4911 (F) You used a pattern of the form C<(*VERB:ARG)> but did not terminate
4912 the pattern with a C<)>. Fix the pattern and retry.
4914 =item Unterminated \g{...} pattern in regex; marked by <-- HERE in m/%s/
4916 (F) You missed a close brace on a \g{..} pattern (group reference) in
4917 a regular expression. Fix the pattern and retry.
4919 =item Unterminated <> operator
4921 (F) The lexer saw a left angle bracket in a place where it was expecting
4922 a term, so it's looking for the corresponding right angle bracket, and
4923 not finding it. Chances are you left some needed parentheses out
4924 earlier in the line, and you really meant a "less than".
4926 =item untie attempted while %d inner references still exist
4928 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
4929 still valid when C<untie> was called.
4931 =item Usage: POSIX::%s(%s)
4933 (F) You called a POSIX function with incorrect arguments.
4934 See L<POSIX/FUNCTIONS> for more information.
4936 =item Usage: Win32::%s(%s)
4938 (F) You called a Win32 function with incorrect arguments.
4939 See L<Win32> for more information.
4941 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in m/%s/
4943 (W regexp) You have used an internal modifier such as (?-o) that has no
4944 meaning unless removed from the entire regexp:
4946 if ($string =~ /(?-o)$pattern/o) { ... }
4950 if ($string =~ /$pattern/) { ... }
4952 The <-- HERE shows in the regular expression about
4953 where the problem was discovered. See L<perlre>.
4955 =item Useless localization of %s
4957 (W syntax) The localization of lvalues such as C<local($x=10)> is
4958 legal, but in fact the local() currently has no effect. This may change at
4959 some point in the future, but in the meantime such code is discouraged.
4961 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
4963 (W regexp) You have used an internal modifier such as (?o) that has no
4964 meaning unless applied to the entire regexp:
4966 if ($string =~ /(?o)$pattern/) { ... }
4970 if ($string =~ /$pattern/o) { ... }
4972 The <-- HERE shows in the regular expression about
4973 where the problem was discovered. See L<perlre>.
4975 =item Useless use of /d modifier in transliteration operator
4977 (W misc) You have used the /d modifier where the searchlist has the
4978 same length as the replacelist. See L<perlop> for more information
4979 about the /d modifier.
4981 =item Useless use of %s in void context
4983 (W void) You did something without a side effect in a context that does
4984 nothing with the return value, such as a statement that doesn't return a
4985 value from a block, or the left side of a scalar comma operator. Very
4986 often this points not to stupidity on your part, but a failure of Perl
4987 to parse your program the way you thought it would. For example, you'd
4988 get this if you mixed up your C precedence with Python precedence and
4993 when you meant to say
4995 ($one, $two) = (1, 2);
4997 Another common error is to use ordinary parentheses to construct a list
4998 reference when you should be using square or curly brackets, for
5003 when you should have said
5007 The square brackets explicitly turn a list value into a scalar value,
5008 while parentheses do not. So when a parenthesized list is evaluated in
5009 a scalar context, the comma is treated like C's comma operator, which
5010 throws away the left argument, which is not what you want. See
5011 L<perlref> for more on this.
5013 This warning will not be issued for numerical constants equal to 0 or 1
5014 since they are often used in statements like
5016 1 while sub_with_side_effects();
5018 String constants that would normally evaluate to 0 or 1 are warned
5021 =item Useless use of "re" pragma
5023 (W) You did C<use re;> without any arguments. That isn't very useful.
5025 =item Useless use of sort in scalar context
5027 (W void) You used sort in scalar context, as in :
5031 This is not very useful, and perl currently optimizes this away.
5033 =item Useless use of %s with no values
5035 (W syntax) You used the push() or unshift() function with no arguments
5036 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
5037 usually have any effect on the array, so is completely useless. It's
5038 possible in principle that push(@tied_array) could have some effect
5039 if the array is tied to a class which implements a PUSH method. If so,
5040 you can write it as C<push(@tied_array,())> to avoid this warning.
5042 =item "use" not allowed in expression
5044 (F) The "use" keyword is recognized and executed at compile time, and
5045 returns no useful value. See L<perlmod>.
5047 =item Use of assignment to $[ is deprecated
5049 (D deprecated) The C<$[> variable (index of the first element in an array)
5050 is deprecated. See L<perlvar/"$[">.
5052 =item Use of bare << to mean <<"" is deprecated
5054 (D deprecated) You are now encouraged to use the explicitly quoted
5055 form if you wish to use an empty line as the terminator of the here-document.
5057 =item Use of comma-less variable list is deprecated
5059 (D deprecated) The values you give to a format should be
5060 separated by commas, not just aligned on a line.
5062 =item Use of chdir('') or chdir(undef) as chdir() deprecated
5064 (D deprecated) chdir() with no arguments is documented to change to
5065 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
5066 behavior, but that has been deprecated. In future versions they
5069 Be careful to check that what you pass to chdir() is defined and not
5070 blank, else you might find yourself in your home directory.
5072 =item Use of /c modifier is meaningless in s///
5074 (W regexp) You used the /c modifier in a substitution. The /c
5075 modifier is not presently meaningful in substitutions.
5077 =item Use of /c modifier is meaningless without /g
5079 (W regexp) You used the /c modifier with a regex operand, but didn't
5080 use the /g modifier. Currently, /c is meaningful only when /g is
5081 used. (This may change in the future.)
5083 =item Use of := for an empty attribute list is not allowed
5085 (F) The construction C<my $x := 42> used to parse as equivalent to
5086 C<my $x : = 42> (applying an empty attribute list to C<$x>).
5087 This construct was deprecated in 5.12.0, and has now been made a syntax
5088 error, so C<:=> can be reclaimed as a new operator in the future.
5090 If you need an empty attribute list, for example in a code generator, add
5091 a space before the C<=>.
5093 =item Use of ?PATTERN? without explicit operator is deprecated
5095 (D deprecated) You have written something like C<?\w?>, for a regular
5096 expression that matches only once. Starting this term directly with
5097 the question mark delimiter is now deprecated, so that the question mark
5098 will be available for use in new operators in the future. Write C<m?\w?>
5099 instead, explicitly using the C<m> operator: the question mark delimiter
5100 still invokes match-once behaviour.
5102 =item Use of freed value in iteration
5104 (F) Perhaps you modified the iterated array within the loop?
5105 This error is typically caused by code like the following:
5108 @a = () for (1,2,@a);
5110 You are not supposed to modify arrays while they are being iterated over.
5111 For speed and efficiency reasons, Perl internally does not do full
5112 reference-counting of iterated items, hence deleting such an item in the
5113 middle of an iteration causes Perl to see a freed value.
5115 =item Use of *glob{FILEHANDLE} is deprecated
5117 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
5118 to access the filehandle slot within a typeglob.
5120 =item Use of /g modifier is meaningless in split
5122 (W regexp) You used the /g modifier on the pattern for a C<split>
5123 operator. Since C<split> always tries to match the pattern
5124 repeatedly, the C</g> has no effect.
5126 =item Use of "goto" to jump into a construct is deprecated
5128 (D deprecated) Using C<goto> to jump from an outer scope into an inner
5129 scope is deprecated and should be avoided.
5131 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
5133 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
5134 are looked up as methods (using the C<@ISA> hierarchy) even when the
5135 subroutines to be autoloaded were called as plain functions (e.g.
5136 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
5139 This bug will be rectified in future by using method lookup only for
5140 methods' C<AUTOLOAD>s. However, there is a significant base of existing
5141 code that may be using the old behavior. So, as an interim step, Perl
5142 currently issues an optional warning when non-methods use inherited
5145 The simple rule is: Inheritance will not work when autoloading
5146 non-methods. The simple fix for old code is: In any module that used
5147 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
5148 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
5151 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
5152 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
5153 C<use AutoLoader 'AUTOLOAD';>.
5155 =item Use of %s in printf format not supported
5157 (F) You attempted to use a feature of printf that is accessible from
5158 only C. This usually means there's a better way to do it in Perl.
5160 =item Use of %s is deprecated
5162 (D deprecated) The construct indicated is no longer recommended for use,
5163 generally because there's a better way to do it, and also because the
5164 old way has bad side effects.
5166 =item Use of %s on a handle without * is deprecated
5168 (D deprecated) You used C<tie>, C<tied> or C<untie> on a scalar but that
5169 scalar happens to hold a typeglob, which means its filehandle will
5170 be tied. If you mean to tie a handle, use an explicit * as in
5173 This is a long-standing bug that will be removed in Perl 5.16, as
5174 there is currently no way to tie the scalar itself when it holds
5175 a typeglob, and no way to untie a scalar that has had a typeglob
5178 =item Use of -l on filehandle %s
5180 (W io) A filehandle represents an opened file, and when you opened the file
5181 it already went past any symlink you are presumably trying to look for.
5182 The operation returned C<undef>. Use a filename instead.
5184 =item Use of "package" with no arguments is deprecated
5186 (D deprecated) You used the C<package> keyword without specifying a package
5187 name. So no namespace is current at all. Using this can cause many
5188 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
5191 =item Use of qw(...) as parentheses is deprecated
5193 (D deprecated) You have something like C<foreach $x qw(a b c) {...}>,
5194 using a C<qw(...)> list literal where a parenthesised expression is
5195 expected. Historically the parser fooled itself into thinking that
5196 C<qw(...)> literals were always enclosed in parentheses, and as a result
5197 you could sometimes omit parentheses around them. (You could never do
5198 the C<foreach qw(a b c) {...}> that you might have expected, though.)
5199 The parser no longer lies to itself in this way. Wrap the list literal
5200 in parentheses, like C<foreach $x (qw(a b c)) {...}>.
5202 =item Use of reference "%s" as array index
5204 (W misc) You tried to use a reference as an array index; this probably
5205 isn't what you mean, because references in numerical context tend
5206 to be huge numbers, and so usually indicates programmer error.
5208 If you really do mean it, explicitly numify your reference, like so:
5209 C<$array[0+$ref]>. This warning is not given for overloaded objects,
5210 either, because you can overload the numification and stringification
5211 operators and then you presumably know what you are doing.
5213 =item Use of reserved word "%s" is deprecated
5215 (D deprecated) The indicated bareword is a reserved word. Future
5216 versions of perl may use it as a keyword, so you're better off either
5217 explicitly quoting the word in a manner appropriate for its context of
5218 use, or using a different name altogether. The warning can be
5219 suppressed for subroutine names by either adding a C<&> prefix, or using
5220 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
5222 =item Use of tainted arguments in %s is deprecated
5224 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
5225 arguments and at least one of them is tainted. This used to be allowed
5226 but will become a fatal error in a future version of perl. Untaint your
5227 arguments. See L<perlsec>.
5229 =item Use of uninitialized value%s
5231 (W uninitialized) An undefined value was used as if it were already
5232 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
5233 To suppress this warning assign a defined value to your variables.
5235 To help you figure out what was undefined, perl will try to tell you the
5236 name of the variable (if any) that was undefined. In some cases it cannot
5237 do this, so it also tells you what operation you used the undefined value
5238 in. Note, however, that perl optimizes your program and the operation
5239 displayed in the warning may not necessarily appear literally in your
5240 program. For example, C<"that $foo"> is usually optimized into C<"that "
5241 . $foo>, and the warning will refer to the C<concatenation (.)> operator,
5242 even though there is no C<.> in your program.
5244 =item Using a hash as a reference is deprecated
5246 (D deprecated) You tried to use a hash as a reference, as in
5247 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
5248 used to allow this syntax, but shouldn't have. It is now deprecated, and will
5249 be removed in a future version.
5251 =item Using an array as a reference is deprecated
5253 (D deprecated) You tried to use an array as a reference, as in
5254 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
5255 allow this syntax, but shouldn't have. It is now deprecated, and will be
5256 removed in a future version.
5258 =item Using !~ with %s doesn't make sense
5260 (F) Using the C<!~> operator with C<s///r>, C<tr///r> or C<y///r> is
5261 currently reserved for future use, as the exact behaviour has not
5262 been decided. (Simply returning the boolean opposite of the
5263 modified string is usually not particularly useful.)
5265 =item Using just the first character returned by \N{} in character class
5267 (W) A charnames handler may return a sequence of more than one character.
5268 Currently all but the first one are discarded when used in a regular
5269 expression pattern bracketed character class.
5271 =item Using just the first characters returned by \N{}
5273 (W) A charnames handler may return a sequence of characters. There is a finite
5274 limit as to the number of characters that can be used, which this sequence
5275 exceeded. In the message, the characters in the sequence are separated by
5276 dots, and each is shown by its ordinal in hex. Anything to the left of the
5277 C<HERE> was retained; anything to the right was discarded.
5279 =item Unicode surrogate U+%X is illegal in UTF-8
5281 =item UTF-16 surrogate U+%X
5283 (W utf8) You had a UTF-16 surrogate in a context where they are
5284 not considered acceptable. These code points, between U+D800 and
5285 U+DFFF (inclusive), are used by Unicode only for UTF-16. However, Perl
5286 internally allows all unsigned integer code points (up to the size limit
5287 available on your platform), including surrogates. But these can cause
5288 problems when being input or output, which is likely where this message
5289 came from. If you really really know what you are doing you can turn
5290 off this warning by C<no warnings 'utf8';>.
5292 =item Value of %s can be "0"; test with defined()
5294 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
5295 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
5296 can return a value of "0"; that would make the conditional expression
5297 false, which is probably not what you intended. When using these
5298 constructs in conditional expressions, test their values with the
5299 C<defined> operator.
5301 =item Value of CLI symbol "%s" too long
5303 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
5304 %ENV element from a CLI symbol table, and found a resultant string
5305 longer than 1024 characters. The return value has been truncated to
5308 =item Variable "%s" is not available
5310 (W closure) During compilation, an inner named subroutine or eval is
5311 attempting to capture an outer lexical that is not currently available.
5312 This can happen for one of two reasons. First, the outer lexical may be
5313 declared in an outer anonymous subroutine that has not yet been created.
5314 (Remember that named subs are created at compile time, while anonymous
5315 subs are created at run-time.) For example,
5317 sub { my $a; sub f { $a } }
5319 At the time that f is created, it can't capture the current value of $a,
5320 since the anonymous subroutine hasn't been created yet. Conversely,
5321 the following won't give a warning since the anonymous subroutine has by
5322 now been created and is live:
5324 sub { my $a; eval 'sub f { $a }' }->();
5326 The second situation is caused by an eval accessing a variable that has
5327 gone out of scope, for example,
5335 Here, when the '$a' in the eval is being compiled, f() is not currently being
5336 executed, so its $a is not available for capture.
5338 =item Variable "%s" is not imported%s
5340 (W misc) With "use strict" in effect, you referred to a global variable
5341 that you apparently thought was imported from another module, because
5342 something else of the same name (usually a subroutine) is exported by
5343 that module. It usually means you put the wrong funny character on the
5344 front of your variable.
5346 =item Variable length lookbehind not implemented in m/%s/
5348 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
5349 known at compile time. See L<perlre>.
5351 =item "%s" variable %s masks earlier declaration in same %s
5353 (W misc) A "my", "our" or "state" variable has been redeclared in the current
5354 scope or statement, effectively eliminating all access to the previous
5355 instance. This is almost always a typographical error. Note that the
5356 earlier variable will still exist until the end of the scope or until
5357 all closure referents to it are destroyed.
5359 =item Variable syntax
5361 (A) You've accidentally run your script through B<csh> instead
5362 of Perl. Check the #! line, or manually feed your script into
5365 =item Variable "%s" will not stay shared
5367 (W closure) An inner (nested) I<named> subroutine is referencing a
5368 lexical variable defined in an outer named subroutine.
5370 When the inner subroutine is called, it will see the value of
5371 the outer subroutine's variable as it was before and during the *first*
5372 call to the outer subroutine; in this case, after the first call to the
5373 outer subroutine is complete, the inner and outer subroutines will no
5374 longer share a common value for the variable. In other words, the
5375 variable will no longer be shared.
5377 This problem can usually be solved by making the inner subroutine
5378 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
5379 reference variables in outer subroutines are created, they
5380 are automatically rebound to the current values of such variables.
5382 =item Verb pattern '%s' has a mandatory argument in regex; marked by <-- HERE in m/%s/
5384 (F) You used a verb pattern that requires an argument. Supply an argument
5385 or check that you are using the right verb.
5387 =item Verb pattern '%s' may not have an argument in regex; marked by <-- HERE in m/%s/
5389 (F) You used a verb pattern that is not allowed an argument. Remove the
5390 argument or check that you are using the right verb.
5392 =item Version number must be a constant number
5394 (P) The attempt to translate a C<use Module n.n LIST> statement into
5395 its equivalent C<BEGIN> block found an internal inconsistency with
5398 =item Version string '%s' contains invalid data; ignoring: '%s'
5400 (W misc) The version string contains invalid characters at the end, which
5403 =item Warning: something's wrong
5405 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
5406 you called it with no args and C<$@> was empty.
5408 =item Warning: unable to close filehandle %s properly
5410 (S) The implicit close() done by an open() got an error indication on
5411 the close(). This usually indicates your file system ran out of disk
5414 =item Warning: Use of "%s" without parentheses is ambiguous
5416 (S ambiguous) You wrote a unary operator followed by something that
5417 looks like a binary operator that could also have been interpreted as a
5418 term or unary operator. For instance, if you know that the rand
5419 function has a default argument of 1.0, and you write
5423 you may THINK you wrote the same thing as
5427 but in actual fact, you got
5431 So put in parentheses to say what you really mean.
5433 =item Wide character in %s
5435 (S utf8) Perl met a wide character (>255) when it wasn't expecting
5436 one. This warning is by default on for I/O (like print). The easiest
5437 way to quiet this warning is simply to add the C<:utf8> layer to the
5438 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
5439 warning is to add C<no warnings 'utf8';> but that is often closer to
5440 cheating. In general, you are supposed to explicitly mark the
5441 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
5443 =item Within []-length '%c' not allowed
5445 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
5446 C<TEMPLATE> always matches the same amount of packed bytes that can be
5447 determined from the template alone. This is not possible if it contains an
5448 of the codes @, /, U, u, w or a *-length. Redesign the template.
5450 =item write() on closed filehandle %s
5452 (W closed) The filehandle you're writing to got itself closed sometime
5453 before now. Check your control flow.
5455 =item %s "\x%X" does not map to Unicode
5457 (F) When reading in different encodings Perl tries to map everything
5458 into Unicode characters. The bytes you read in are not legal in
5459 this encoding, for example
5461 utf8 "\xE4" does not map to Unicode
5463 if you try to read in the a-diaereses Latin-1 as UTF-8.
5465 =item 'X' outside of string
5467 (F) You had a (un)pack template that specified a relative position before
5468 the beginning of the string being (un)packed. See L<perlfunc/pack>.
5470 =item 'x' outside of string in unpack
5472 (F) You had a pack template that specified a relative position after
5473 the end of the string being unpacked. See L<perlfunc/pack>.
5475 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
5477 (F) And you probably never will, because you probably don't have the
5478 sources to your kernel, and your vendor probably doesn't give a rip
5479 about what you want. Your best bet is to put a setuid C wrapper around
5482 =item You need to quote "%s"
5484 (W syntax) You assigned a bareword as a signal handler name.
5485 Unfortunately, you already have a subroutine of that name declared,
5486 which means that Perl 5 will try to call the subroutine when the
5487 assignment is executed, which is probably not what you want. (If it IS
5488 what you want, put an & in front.)
5490 =item Your random numbers are not that random
5492 (F) When trying to initialise the random seed for hashes, Perl could
5493 not get any randomness out of your system. This usually indicates
5494 Something Very Wrong.
5500 L<warnings>, L<perllexwarn>.