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 (optional).
12 (S) A severe warning (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<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Default warnings are always enabled unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Allocation too large: %lx
55 (X) You can't allocate more than 64K on an MS-DOS machine.
57 =item '%c' allowed only after types %s
59 (F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60 after certain types. See L<perlfunc/pack>.
62 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
64 (W ambiguous) A subroutine you have declared has the same name as a Perl
65 keyword, and you have used the name without qualification for calling
66 one or the other. Perl decided to call the builtin because the
67 subroutine is not imported.
69 To force interpretation as a subroutine call, either put an ampersand
70 before the subroutine name, or qualify the name with its package.
71 Alternatively, you can import the subroutine (or pretend that it's
72 imported with the C<use subs> pragma).
74 To silently interpret it as the Perl operator, use the C<CORE::> prefix
75 on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
76 to be an object method (see L<perlsub/"Subroutine Attributes"> or
79 =item Ambiguous range in transliteration operator
81 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82 all. To include a C<-> character in a transliteration, put it either
83 first or last. (In the past, C<tr/a-z-0//> was synonymous with
84 C<tr/a-y//>, which was probably not what you would have expected.)
86 =item Ambiguous use of %s resolved as %s
88 (W ambiguous)(S) You said something that may not be interpreted the way
89 you thought. Normally it's pretty easy to disambiguate it by supplying
90 a missing quote, operator, parenthesis pair or declaration.
92 =item '|' and '<' may not both be specified on command line
94 (F) An error peculiar to VMS. Perl does its own command line
95 redirection, and found that STDIN was a pipe, and that you also tried to
96 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
98 =item '|' and '>' may not both be specified on command line
100 (F) An error peculiar to VMS. Perl does its own command line
101 redirection, and thinks you tried to redirect stdout both to a file and
102 into a pipe to another command. You need to choose one or the other,
103 though nothing's stopping you from piping into a program or Perl script
104 which 'splits' output into two streams, such as
106 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
113 =item Applying %s to %s will act on scalar(%s)
115 (W misc) The pattern match (C<//>), substitution (C<s///>), and
116 transliteration (C<tr///>) operators work on scalar values. If you apply
117 one of them to an array or a hash, it will convert the array or hash to
118 a scalar value -- the length of an array, or the population info of a
119 hash -- and then work on that scalar value. This is probably not what
120 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
123 =item Args must match #! line
125 (F) The setuid emulator requires that the arguments Perl was invoked
126 with match the arguments specified on the #! line. Since some systems
127 impose a one-argument limit on the #! line, try combining switches;
128 for example, turn C<-w -U> into C<-wU>.
130 =item Arg too short for msgsnd
132 (F) msgsnd() requires a string at least as long as sizeof(long).
134 =item %s argument is not a HASH or ARRAY element
136 (F) The argument to exists() must be a hash or array element, such as:
141 =item %s argument is not a HASH or ARRAY element or slice
143 (F) The argument to delete() must be either a hash or array element,
149 or a hash or array slice, such as:
151 @foo[$bar, $baz, $xyzzy]
152 @{$ref->[12]}{"susie", "queue"}
154 =item %s argument is not a subroutine name
156 (F) The argument to exists() for C<exists &sub> must be a subroutine
157 name, and not a subroutine call. C<exists &sub()> will generate this
160 =item Argument "%s" isn't numeric%s
162 (W numeric) The indicated string was fed as an argument to an operator
163 that expected a numeric value instead. If you're fortunate the message
164 will identify which operator was so unfortunate.
166 =item Argument list not closed for PerlIO layer "%s"
168 (W layer) When pushing a layer with arguments onto the Perl I/O system you
169 forgot the ) that closes the argument list. (Layers take care of transforming
170 data between external and internal representations.) Perl stopped parsing
171 the layer list at this point and did not attempt to push this layer.
172 If your program didn't explicitly request the failing operation, it may be
173 the result of the value of the environment variable PERLIO.
175 =item Array @%s missing the @ in argument %d of %s()
177 (D deprecated) Really old Perl let you omit the @ on array names in some
178 spots. This is now heavily deprecated.
180 =item assertion botched: %s
182 (P) The malloc package that comes with Perl had an internal failure.
184 =item Assertion failed: file "%s"
186 (P) A general assertion failed. The file in question must be examined.
188 =item Assignment to both a list and a scalar
190 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
191 must either both be scalars or both be lists. Otherwise Perl won't
192 know which context to supply to the right side.
194 =item A thread exited while %d threads were running
196 (W) When using threaded Perl, a thread (not necessarily the main
197 thread) exited while there were still other threads running.
198 Usually it's a good idea to first collect the return values of the
199 created threads by joining them, and only then exit from the main
200 thread. See L<threads>.
202 =item Attempt to access disallowed key '%s' in a restricted hash
204 (F) The failing code has attempted to get or set a key which is not in
205 the current set of allowed keys of a restricted hash.
207 =item Attempt to bless into a reference
209 (F) The CLASSNAME argument to the bless() operator is expected to be
210 the name of the package to bless the resulting object into. You've
211 supplied instead a reference to something: perhaps you wrote
217 bless $self, ref($proto) || $proto;
219 If you actually want to bless into the stringified version
220 of the reference supplied, you need to stringify it yourself, for
223 bless $self, "$proto";
225 =item Attempt to delete disallowed key '%s' from a restricted hash
227 (F) The failing code attempted to delete from a restricted hash a key
228 which is not in its key set.
230 =item Attempt to delete readonly key '%s' from a restricted hash
232 (F) The failing code attempted to delete a key whose value has been
233 declared readonly from a restricted hash.
235 =item Attempt to free non-arena SV: 0x%lx
237 (P internal) All SV objects are supposed to be allocated from arenas
238 that will be garbage collected on exit. An SV was discovered to be
239 outside any of those arenas.
241 =item Attempt to free nonexistent shared string
243 (P internal) Perl maintains a reference counted internal table of
244 strings to optimize the storage and access of hash keys and other
245 strings. This indicates someone tried to decrement the reference count
246 of a string that can no longer be found in the table.
248 =item Attempt to free temp prematurely
250 (W debugging) Mortalized values are supposed to be freed by the
251 free_tmps() routine. This indicates that something else is freeing the
252 SV before the free_tmps() routine gets a chance, which means that the
253 free_tmps() routine will be freeing an unreferenced scalar when it does
256 =item Attempt to free unreferenced glob pointers
258 (P internal) The reference counts got screwed up on symbol aliases.
260 =item Attempt to free unreferenced scalar
262 (W internal) Perl went to decrement the reference count of a scalar to
263 see if it would go to 0, and discovered that it had already gone to 0
264 earlier, and should have been freed, and in fact, probably was freed.
265 This could indicate that SvREFCNT_dec() was called too many times, or
266 that SvREFCNT_inc() was called too few times, or that the SV was
267 mortalized when it shouldn't have been, or that memory has been
270 =item Attempt to join self
272 (F) You tried to join a thread from within itself, which is an
273 impossible task. You may be joining the wrong thread, or you may need
274 to move the join() to some other thread.
276 =item Attempt to pack pointer to temporary value
278 (W pack) You tried to pass a temporary value (like the result of a
279 function, or a computed expression) to the "p" pack() template. This
280 means the result contains a pointer to a location that could become
281 invalid anytime, even before the end of the current statement. Use
282 literals or global values as arguments to the "p" pack() template to
285 =item Attempt to use reference as lvalue in substr
287 (W substr) You supplied a reference as the first argument to substr()
288 used as an lvalue, which is pretty strange. Perhaps you forgot to
289 dereference it first. See L<perlfunc/substr>.
291 =item Bad arg length for %s, is %d, should be %s
293 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
294 or shmctl(). In C parlance, the correct sizes are, respectively,
295 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
296 S<sizeof(struct shmid_ds *)>.
298 =item Bad evalled substitution pattern
300 (F) You've used the C</e> switch to evaluate the replacement for a
301 substitution, but perl found a syntax error in the code to evaluate,
302 most likely an unexpected right brace '}'.
304 =item Bad filehandle: %s
306 (F) A symbol was passed to something wanting a filehandle, but the
307 symbol has no filehandle associated with it. Perhaps you didn't do an
308 open(), or did it in another package.
310 =item Bad free() ignored
312 (S malloc) An internal routine called free() on something that had never
313 been malloc()ed in the first place. Mandatory, but can be disabled by
314 setting environment variable C<PERL_BADFREE> to 0.
316 This message can be seen quite often with DB_File on systems with "hard"
317 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
318 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
322 (P) One of the internal hash routines was passed a null HV pointer.
324 =item Badly placed ()'s
326 (A) You've accidentally run your script through B<csh> instead
327 of Perl. Check the #! line, or manually feed your script into
330 =item Bad name after %s::
332 (F) You started to name a symbol by using a package prefix, and then
333 didn't finish the symbol. In particular, you can't interpolate outside
342 $sym = "mypack::$var";
344 =item Bad realloc() ignored
346 (S malloc) An internal routine called realloc() on something that had
347 never been malloc()ed in the first place. Mandatory, but can be disabled
348 by setting environment variable C<PERL_BADFREE> to 1.
350 =item Bad symbol for array
352 (P) An internal request asked to add an array entry to something that
353 wasn't a symbol table entry.
355 =item Bad symbol for filehandle
357 (P) An internal request asked to add a filehandle entry to something
358 that wasn't a symbol table entry.
360 =item Bad symbol for hash
362 (P) An internal request asked to add a hash entry to something that
363 wasn't a symbol table entry.
365 =item Bareword found in conditional
367 (W bareword) The compiler found a bareword where it expected a
368 conditional, which often indicates that an || or && was parsed as part
369 of the last argument of the previous construct, for example:
373 It may also indicate a misspelled constant that has been interpreted as
376 use constant TYPO => 1;
377 if (TYOP) { print "foo" }
379 The C<strict> pragma is useful in avoiding such errors.
381 =item Bareword "%s" not allowed while "strict subs" in use
383 (F) With "strict subs" in use, a bareword is only allowed as a
384 subroutine identifier, in curly brackets or to the left of the "=>"
385 symbol. Perhaps you need to predeclare a subroutine?
387 =item Bareword "%s" refers to nonexistent package
389 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
390 compiler saw no other uses of that namespace before that point. Perhaps
391 you need to predeclare a package?
393 =item BEGIN failed--compilation aborted
395 (F) An untrapped exception was raised while executing a BEGIN
396 subroutine. Compilation stops immediately and the interpreter is
399 =item BEGIN not safe after errors--compilation aborted
401 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
402 implies a C<BEGIN {}>) after one or more compilation errors had already
403 occurred. Since the intended environment for the C<BEGIN {}> could not
404 be guaranteed (due to the errors), and since subsequent code likely
405 depends on its correct operation, Perl just gave up.
407 =item \1 better written as $1
409 (W syntax) Outside of patterns, backreferences live on as variables.
410 The use of backslashes is grandfathered on the right-hand side of a
411 substitution, but stylistically it's better to use the variable form
412 because other Perl programmers will expect it, and it works better if
413 there are more than 9 backreferences.
415 =item Binary number > 0b11111111111111111111111111111111 non-portable
417 (W portable) The binary number you specified is larger than 2**32-1
418 (4294967295) and therefore non-portable between systems. See
419 L<perlport> for more on portability concerns.
421 =item bind() on closed socket %s
423 (W closed) You tried to do a bind on a closed socket. Did you forget to
424 check the return value of your socket() call? See L<perlfunc/bind>.
426 =item binmode() on closed filehandle %s
428 (W unopened) You tried binmode() on a filehandle that was never opened.
429 Check you control flow and number of arguments.
431 =item Bit vector size > 32 non-portable
433 (W portable) Using bit vector sizes larger than 32 is non-portable.
435 =item Bizarre copy of %s in %s
437 (P) Perl detected an attempt to copy an internal value that is not
440 =item Buffer overflow in prime_env_iter: %s
442 (W internal) A warning peculiar to VMS. While Perl was preparing to
443 iterate over %ENV, it encountered a logical name or symbol definition
444 which was too long, so it was truncated to the string shown.
446 =item Callback called exit
448 (F) A subroutine invoked from an external package via call_sv()
449 exited by calling exit.
451 =item %s() called too early to check prototype
453 (W prototype) You've called a function that has a prototype before the
454 parser saw a definition or declaration for it, and Perl could not check
455 that the call conforms to the prototype. You need to either add an
456 early prototype declaration for the subroutine in question, or move the
457 subroutine definition ahead of the call to get proper prototype
458 checking. Alternatively, if you are certain that you're calling the
459 function correctly, you may put an ampersand before the name to avoid
460 the warning. See L<perlsub>.
462 =item Cannot compress integer in pack
464 (F) An argument to pack("w",...) was too large to compress. The BER
465 compressed integer format can only be used with positive integers, and you
466 attempted to compress Infinity or a very large number (> 1e308).
467 See L<perlfunc/pack>.
469 =item Cannot compress negative numbers in pack
471 (F) An argument to pack("w",...) was negative. The BER compressed integer
472 format can only be used with positive integers. See L<perlfunc/pack>.
474 =item Can only compress unsigned integers in pack
476 (F) An argument to pack("w",...) was not an integer. The BER compressed
477 integer format can only be used with positive integers, and you attempted
478 to compress something else. See L<perlfunc/pack>.
480 =item Can't bless non-reference value
482 (F) Only hard references may be blessed. This is how Perl "enforces"
483 encapsulation of objects. See L<perlobj>.
485 =item Can't call method "%s" in empty package "%s"
487 (F) You called a method correctly, and it correctly indicated a package
488 functioning as a class, but that package doesn't have ANYTHING defined
489 in it, let alone methods. See L<perlobj>.
491 =item Can't call method "%s" on an undefined value
493 (F) You used the syntax of a method call, but the slot filled by the
494 object reference or package name contains an undefined value. Something
495 like this will reproduce the error:
498 process $BADREF 1,2,3;
499 $BADREF->process(1,2,3);
501 =item Can't call method "%s" on unblessed reference
503 (F) A method call must know in what package it's supposed to run. It
504 ordinarily finds this out from the object reference you supply, but you
505 didn't supply an object reference in this case. A reference isn't an
506 object reference until it has been blessed. See L<perlobj>.
508 =item Can't call method "%s" without a package or object reference
510 (F) You used the syntax of a method call, but the slot filled by the
511 object reference or package name contains an expression that returns a
512 defined value which is neither an object reference nor a package name.
513 Something like this will reproduce the error:
516 process $BADREF 1,2,3;
517 $BADREF->process(1,2,3);
519 =item Can't chdir to %s
521 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
522 that you can chdir to, possibly because it doesn't exist.
524 =item Can't check filesystem of script "%s" for nosuid
526 (P) For some reason you can't check the filesystem of the script for
529 =item Can't coerce array into hash
531 (F) You used an array where a hash was expected, but the array has no
532 information on how to map from keys to array indices. You can do that
533 only with arrays that have a hash reference at index 0.
535 =item Can't coerce %s to integer in %s
537 (F) Certain types of SVs, in particular real symbol table entries
538 (typeglobs), can't be forced to stop being what they are. So you can't
548 but then $foo no longer contains a glob.
550 =item Can't coerce %s to number in %s
552 (F) Certain types of SVs, in particular real symbol table entries
553 (typeglobs), can't be forced to stop being what they are.
555 =item Can't coerce %s to string in %s
557 (F) Certain types of SVs, in particular real symbol table entries
558 (typeglobs), can't be forced to stop being what they are.
560 =item Can't create pipe mailbox
562 (P) An error peculiar to VMS. The process is suffering from exhausted
563 quotas or other plumbing problems.
565 =item Can't declare class for non-scalar %s in "%s"
567 (F) Currently, only scalar variables can be declared with a specific
568 class qualifier in a "my" or "our" declaration. The semantics may be
569 extended for other types of variables in future.
571 =item Can't declare %s in "%s"
573 (F) Only scalar, array, and hash variables may be declared as "my" or
574 "our" variables. They must have ordinary identifiers as names.
576 =item Can't do inplace edit: %s is not a regular file
578 (S inplace) You tried to use the B<-i> switch on a special file, such as
579 a file in /dev, or a FIFO. The file was ignored.
581 =item Can't do inplace edit on %s: %s
583 (S inplace) The creation of the new file failed for the indicated
586 =item Can't do inplace edit without backup
588 (F) You're on a system such as MS-DOS that gets confused if you try
589 reading from a deleted (but still opened) file. You have to say
590 C<-i.bak>, or some such.
592 =item Can't do inplace edit: %s would not be unique
594 (S inplace) Your filesystem does not support filenames longer than 14
595 characters and Perl was unable to create a unique filename during
596 inplace editing with the B<-i> switch. The file was ignored.
598 =item Can't do {n,m} with n > m in regex; marked by <-- HERE in m/%s/
600 (F) Minima must be less than or equal to maxima. If you really want your
601 regexp to match something 0 times, just put {0}. The <-- HERE shows in the
602 regular expression about where the problem was discovered. See L<perlre>.
604 =item Can't do setegid!
606 (P) The setegid() call failed for some reason in the setuid emulator of
609 =item Can't do seteuid!
611 (P) The setuid emulator of suidperl failed for some reason.
613 =item Can't do setuid
615 (F) This typically means that ordinary perl tried to exec suidperl to do
616 setuid emulation, but couldn't exec it. It looks for a name of the form
617 sperl5.000 in the same directory that the perl executable resides under
618 the name perl5.000, typically /usr/local/bin on Unix machines. If the
619 file is there, check the execute permissions. If it isn't, ask your
620 sysadmin why he and/or she removed it.
622 =item Can't do waitpid with flags
624 (F) This machine doesn't have either waitpid() or wait4(), so only
625 waitpid() without flags is emulated.
627 =item Can't emulate -%s on #! line
629 (F) The #! line specifies a switch that doesn't make sense at this
630 point. For example, it'd be kind of silly to put a B<-x> on the #!
633 =item Can't %s %s-endian %ss on this platform
635 (F) Your platform's byte-order is neither big-endian nor little-endian,
636 or it has a very strange pointer size. Packing and unpacking big- or
637 little-endian floating point values and pointers may not be possible.
638 See L<perlfunc/pack>.
640 =item Can't exec "%s": %s
642 (W exec) A system(), exec(), or piped open call could not execute the
643 named program for the indicated reason. Typical reasons include: the
644 permissions were wrong on the file, the file wasn't found in
645 C<$ENV{PATH}>, the executable in question was compiled for another
646 architecture, or the #! line in a script points to an interpreter that
647 can't be run for similar reasons. (Or maybe your system doesn't support
652 (F) Perl was trying to execute the indicated program for you because
653 that's what the #! line said. If that's not what you wanted, you may
654 need to mention "perl" on the #! line somewhere.
656 =item Can't execute %s
658 (F) You used the B<-S> switch, but the copies of the script to execute
659 found in the PATH did not have correct permissions.
661 =item Can't find an opnumber for "%s"
663 (F) A string of a form C<CORE::word> was given to prototype(), but there
664 is no builtin with the name C<word>.
666 =item Can't find %s character property "%s"
668 (F) You used C<\p{}> or C<\P{}> but the character property by that name
669 could not be found. Maybe you misspelled the name of the property
670 (remember that the names of character properties consist only of
671 alphanumeric characters), or maybe you forgot the C<Is> or C<In> prefix?
673 =item Can't find label %s
675 (F) You said to goto a label that isn't mentioned anywhere that it's
676 possible for us to go to. See L<perlfunc/goto>.
678 =item Can't find %s on PATH
680 (F) You used the B<-S> switch, but the script to execute could not be
683 =item Can't find %s on PATH, '.' not in PATH
685 (F) You used the B<-S> switch, but the script to execute could not be
686 found in the PATH, or at least not with the correct permissions. The
687 script exists in the current directory, but PATH prohibits running it.
689 =item Can't find %s property definition %s
691 (F) You may have tried to use C<\p> which means a Unicode property (for
692 example C<\p{Lu}> is all uppercase letters). If you did mean to use a
693 Unicode property, see L<perlunicode> for the list of known properties.
694 If you didn't mean to use a Unicode property, escape the C<\p>, either
695 by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, until
698 =item Can't find string terminator %s anywhere before EOF
700 (F) Perl strings can stretch over multiple lines. This message means
701 that the closing delimiter was omitted. Because bracketed quotes count
702 nesting levels, the following is missing its final parenthesis:
704 print q(The character '(' starts a side comment.);
706 If you're getting this error from a here-document, you may have included
707 unseen whitespace before or after your closing tag. A good programmer's
708 editor will have a way to help you find these characters.
712 (F) A fatal error occurred while trying to fork while opening a
715 =item Can't get filespec - stale stat buffer?
717 (S) A warning peculiar to VMS. This arises because of the difference
718 between access checks under VMS and under the Unix model Perl assumes.
719 Under VMS, access checks are done by filename, rather than by bits in
720 the stat buffer, so that ACLs and other protections can be taken into
721 account. Unfortunately, Perl assumes that the stat buffer contains all
722 the necessary information, and passes it, instead of the filespec, to
723 the access checking routine. It will try to retrieve the filespec using
724 the device name and FID present in the stat buffer, but this works only
725 if you haven't made a subsequent call to the CRTL stat() routine,
726 because the device name is overwritten with each call. If this warning
727 appears, the name lookup failed, and the access checking routine gave up
728 and returned FALSE, just to be conservative. (Note: The access checking
729 routine knows about the Perl C<stat> operator and file tests, so you
730 shouldn't ever see this warning in response to a Perl command; it arises
731 only if some internal code takes stat buffers lightly.)
733 =item Can't get pipe mailbox device name
735 (P) An error peculiar to VMS. After creating a mailbox to act as a
736 pipe, Perl can't retrieve its name for later use.
738 =item Can't get SYSGEN parameter value for MAXBUF
740 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
741 mailbox buffers to be, and didn't get an answer.
743 =item Can't "goto" into the middle of a foreach loop
745 (F) A "goto" statement was executed to jump into the middle of a foreach
746 loop. You can't get there from here. See L<perlfunc/goto>.
748 =item Can't "goto" out of a pseudo block
750 (F) A "goto" statement was executed to jump out of what might look like
751 a block, except that it isn't a proper block. This usually occurs if
752 you tried to jump out of a sort() block or subroutine, which is a no-no.
753 See L<perlfunc/goto>.
755 =item Can't goto subroutine from an eval-string
757 (F) The "goto subroutine" call can't be used to jump out of an eval
758 "string". (You can use it to jump out of an eval {BLOCK}, but you
759 probably don't want to.)
761 =item Can't goto subroutine outside a subroutine
763 (F) The deeply magical "goto subroutine" call can only replace one
764 subroutine call for another. It can't manufacture one out of whole
765 cloth. In general you should be calling it out of only an AUTOLOAD
766 routine anyway. See L<perlfunc/goto>.
768 =item Can't ignore signal CHLD, forcing to default
770 (W signal) Perl has detected that it is being run with the SIGCHLD
771 signal (sometimes known as SIGCLD) disabled. Since disabling this
772 signal will interfere with proper determination of exit status of child
773 processes, Perl has reset the signal to its default value. This
774 situation typically indicates that the parent program under which Perl
775 may be running (e.g. cron) is being very careless.
777 =item Can't "last" outside a loop block
779 (F) A "last" statement was executed to break out of the current block,
780 except that there's this itty bitty problem called there isn't a current
781 block. Note that an "if" or "else" block doesn't count as a "loopish"
782 block, as doesn't a block given to sort(), map() or grep(). You can
783 usually double the curlies to get the same effect though, because the
784 inner curlies will be considered a block that loops once. See
787 =item Can't localize lexical variable %s
789 (F) You used local on a variable name that was previously declared as a
790 lexical variable using "my". This is not allowed. If you want to
791 localize a package variable of the same name, qualify it with the
794 =item Can't localize through a reference
796 (F) You said something like C<local $$ref>, which Perl can't currently
797 handle, because when it goes to restore the old value of whatever $ref
798 pointed to after the scope of the local() is finished, it can't be sure
799 that $ref will still be a reference.
801 =item Can't locate %s
803 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be
804 found. Perl looks for the file in all the locations mentioned in @INC,
805 unless the file name included the full path to the file. Perhaps you
806 need to set the PERL5LIB or PERL5OPT environment variable to say where
807 the extra library is, or maybe the script needs to add the library name
808 to @INC. Or maybe you just misspelled the name of the file. See
809 L<perlfunc/require> and L<lib>.
811 =item Can't locate auto/%s.al in @INC
813 (F) A function (or method) was called in a package which allows
814 autoload, but there is no function to autoload. Most probable causes
815 are a misprint in a function/method name or a failure to C<AutoSplit>
816 the file, say, by doing C<make install>.
818 =item Can't locate object method "%s" via package "%s"
820 (F) You called a method correctly, and it correctly indicated a package
821 functioning as a class, but that package doesn't define that particular
822 method, nor does any of its base classes. See L<perlobj>.
824 =item Can't locate package %s for @%s::ISA
826 (W syntax) The @ISA array contained the name of another package that
827 doesn't seem to exist.
829 =item Can't locate PerlIO%s
831 (F) You tried to use in open() a PerlIO layer that does not exist,
832 e.g. open(FH, ">:nosuchlayer", "somefile").
834 =item Can't make list assignment to \%ENV on this system
836 (F) List assignment to %ENV is not supported on some systems, notably
839 =item Can't modify %s in %s
841 (F) You aren't allowed to assign to the item indicated, or otherwise try
842 to change it, such as with an auto-increment.
844 =item Can't modify nonexistent substring
846 (P) The internal routine that does assignment to a substr() was handed
849 =item Can't modify non-lvalue subroutine call
851 (F) Subroutines meant to be used in lvalue context should be declared as
852 such, see L<perlsub/"Lvalue subroutines">.
854 =item Can't msgrcv to read-only var
856 (F) The target of a msgrcv must be modifiable to be used as a receive
859 =item Can't "next" outside a loop block
861 (F) A "next" statement was executed to reiterate the current block, but
862 there isn't a current block. Note that an "if" or "else" block doesn't
863 count as a "loopish" block, as doesn't a block given to sort(), map() or
864 grep(). You can usually double the curlies to get the same effect
865 though, because the inner curlies will be considered a block that loops
866 once. See L<perlfunc/next>.
868 =item Can't open %s: %s
870 (S inplace) The implicit opening of a file through use of the C<< <> >>
871 filehandle, either implicitly under the C<-n> or C<-p> command-line
872 switches, or explicitly, failed for the indicated reason. Usually this
873 is because you don't have read permission for a file which you named on
876 =item Can't open a reference
878 (W io) You tried to open a scalar reference for reading or writing,
879 using the 3-arg open() syntax :
883 but your version of perl is compiled without perlio, and this form of
884 open is not supported.
886 =item Can't open bidirectional pipe
888 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
889 You can try any of several modules in the Perl library to do this, such
890 as IPC::Open2. Alternately, direct the pipe's output to a file using
891 ">", and then read it in under a different file handle.
893 =item Can't open error file %s as stderr
895 (F) An error peculiar to VMS. Perl does its own command line
896 redirection, and couldn't open the file specified after '2>' or '2>>' on
897 the command line for writing.
899 =item Can't open input file %s as stdin
901 (F) An error peculiar to VMS. Perl does its own command line
902 redirection, and couldn't open the file specified after '<' on the
903 command line for reading.
905 =item Can't open output file %s as stdout
907 (F) An error peculiar to VMS. Perl does its own command line
908 redirection, and couldn't open the file specified after '>' or '>>' on
909 the command line for writing.
911 =item Can't open output pipe (name: %s)
913 (P) An error peculiar to VMS. Perl does its own command line
914 redirection, and couldn't open the pipe into which to send data destined
917 =item Can't open perl script%s
919 (F) The script you specified can't be opened for the indicated reason.
921 =item Can't read CRTL environ
923 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
924 from the CRTL's internal environment array and discovered the array was
925 missing. You need to figure out where your CRTL misplaced its environ
926 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
929 =item Can't redefine active sort subroutine %s
931 (F) Perl optimizes the internal handling of sort subroutines and keeps
932 pointers into them. You tried to redefine one such sort subroutine when
933 it was currently active, which is not allowed. If you really want to do
934 this, you should write C<sort { &func } @x> instead of C<sort func @x>.
936 =item Can't "redo" outside a loop block
938 (F) A "redo" statement was executed to restart the current block, but
939 there isn't a current block. Note that an "if" or "else" block doesn't
940 count as a "loopish" block, as doesn't a block given to sort(), map()
941 or grep(). You can usually double the curlies to get the same effect
942 though, because the inner curlies will be considered a block that
943 loops once. See L<perlfunc/redo>.
945 =item Can't remove %s: %s, skipping file
947 (S inplace) You requested an inplace edit without creating a backup
948 file. Perl was unable to remove the original file to replace it with
949 the modified file. The file was left unmodified.
951 =item Can't rename %s to %s: %s, skipping file
953 (S inplace) The rename done by the B<-i> switch failed for some reason,
954 probably because you don't have write permission to the directory.
956 =item Can't reopen input pipe (name: %s) in binary mode
958 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
959 to reopen it to accept binary data. Alas, it failed.
961 =item Can't resolve method `%s' overloading `%s' in package `%s'
963 (F|P) Error resolving overloading specified by a method name (as opposed
964 to a subroutine reference): no such method callable via the package. If
965 method name is C<???>, this is an internal error.
967 =item Can't reswap uid and euid
969 (P) The setreuid() call failed for some reason in the setuid emulator of
972 =item Can't return %s from lvalue subroutine
974 (F) Perl detected an attempt to return illegal lvalues (such as
975 temporary or readonly values) from a subroutine used as an lvalue. This
978 =item Can't return outside a subroutine
980 (F) The return statement was executed in mainline code, that is, where
981 there was no subroutine call to return out of. See L<perlsub>.
983 =item Can't return %s to lvalue scalar context
985 (F) You tried to return a complete array or hash from an lvalue subroutine,
986 but you called the subroutine in a way that made Perl think you meant
987 to return only one value. You probably meant to write parentheses around
988 the call to the subroutine, which tell Perl that the call should be in
991 =item Can't stat script "%s"
993 (P) For some reason you can't fstat() the script even though you have it
994 open already. Bizarre.
996 =item Can't swap uid and euid
998 (P) The setreuid() call failed for some reason in the setuid emulator of
1001 =item Can't take log of %g
1003 (F) For ordinary real numbers, you can't take the logarithm of a
1004 negative number or zero. There's a Math::Complex package that comes
1005 standard with Perl, though, if you really want to do that for the
1008 =item Can't take sqrt of %g
1010 (F) For ordinary real numbers, you can't take the square root of a
1011 negative number. There's a Math::Complex package that comes standard
1012 with Perl, though, if you really want to do that.
1014 =item Can't undef active subroutine
1016 (F) You can't undefine a routine that's currently running. You can,
1017 however, redefine it while it's running, and you can even undef the
1018 redefined subroutine while the old routine is running. Go figure.
1022 (F) You tried to unshift an "unreal" array that can't be unshifted, such
1023 as the main Perl stack.
1025 =item Can't upgrade that kind of scalar
1027 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1028 into a more specialized kind of SV. The top several SV types are so
1029 specialized, however, that they cannot be interconverted. This message
1030 indicates that such a conversion was attempted.
1032 =item Can't upgrade to undef
1034 (P) The undefined SV is the bottom of the totem pole, in the scheme of
1035 upgradability. Upgrading to undef indicates an error in the code
1038 =item Can't use '%c' in a group with different byte-order in %s
1040 (F) You attempted to force a different byte-order on a type
1041 that is already inside a group with a byte-order modifier.
1042 For example you cannot force little-endianness on a type that
1043 is inside a big-endian group.
1045 =item Can't use anonymous symbol table for method lookup
1047 (F) The internal routine that does method lookup was handed a symbol
1048 table that doesn't have a name. Symbol tables can become anonymous
1049 for example by undefining stashes: C<undef %Some::Package::>.
1051 =item Can't use an undefined value as %s reference
1053 (F) A value used as either a hard reference or a symbolic reference must
1054 be a defined value. This helps to delurk some insidious errors.
1056 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1058 (F) Only hard references are allowed by "strict refs". Symbolic
1059 references are disallowed. See L<perlref>.
1061 =item Can't use %! because Errno.pm is not available
1063 (F) The first time the %! hash is used, perl automatically loads the
1064 Errno.pm module. The Errno module is expected to tie the %! hash to
1065 provide symbolic names for C<$!> errno values.
1067 =item Can't use both '<' and '>' after type '%c' in %s
1069 (F) A type cannot be forced to have both big-endian and little-endian
1070 byte-order at the same time, so this combination of modifiers is not
1071 allowed. See L<perlfunc/pack>.
1073 =item Can't use %s for loop variable
1075 (F) Only a simple scalar variable may be used as a loop variable on a
1078 =item Can't use global %s in "my"
1080 (F) You tried to declare a magical variable as a lexical variable. This
1081 is not allowed, because the magic can be tied to only one location
1082 (namely the global variable) and it would be incredibly confusing to
1083 have variables in your program that looked like magical variables but
1086 =item Can't use "my %s" in sort comparison
1088 (F) The global variables $a and $b are reserved for sort comparisons.
1089 You mentioned $a or $b in the same line as the <=> or cmp operator,
1090 and the variable had earlier been declared as a lexical variable.
1091 Either qualify the sort variable with the package name, or rename the
1094 =item Can't use %s ref as %s ref
1096 (F) You've mixed up your reference types. You have to dereference a
1097 reference of the type needed. You can use the ref() function to
1098 test the type of the reference, if need be.
1100 =item Can't use string ("%s") as %s ref while "strict refs" in use
1102 (F) Only hard references are allowed by "strict refs". Symbolic
1103 references are disallowed. See L<perlref>.
1105 =item Can't use subscript on %s
1107 (F) The compiler tried to interpret a bracketed expression as a
1108 subscript. But to the left of the brackets was an expression that
1109 didn't look like an array reference, or anything else subscriptable.
1111 =item Can't use \%c to mean $%c in expression
1113 (W syntax) In an ordinary expression, backslash is a unary operator that
1114 creates a reference to its argument. The use of backslash to indicate a
1115 backreference to a matched substring is valid only as part of a regular
1116 expression pattern. Trying to do this in ordinary Perl code produces a
1117 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1120 =item Can't weaken a nonreference
1122 (F) You attempted to weaken something that was not a reference. Only
1123 references can be weakened.
1125 =item Can't x= to read-only value
1127 (F) You tried to repeat a constant value (often the undefined value)
1128 with an assignment operator, which implies modifying the value itself.
1129 Perhaps you need to copy the value to a temporary, and repeat that.
1131 =item Character in "C" format wrapped in pack
1137 where $x is either less than 0 or more than 255; the C<"C"> format is
1138 only for encoding native operating system characters (ASCII, EBCDIC,
1139 and so on) and not for Unicode characters, so Perl behaved as if you meant
1143 If you actually want to pack Unicode codepoints, use the C<"U"> format
1146 =item Character in "c" format wrapped in pack
1152 where $x is either less than -128 or more than 127; the C<"c"> format
1153 is only for encoding native operating system characters (ASCII, EBCDIC,
1154 and so on) and not for Unicode characters, so Perl behaved as if you meant
1156 pack("c", $x & 255);
1158 If you actually want to pack Unicode codepoints, use the C<"U"> format
1161 =item close() on unopened filehandle %s
1163 (W unopened) You tried to close a filehandle that was never opened.
1165 =item Code missing after '/'
1167 (F) You had a (sub-)template that ends with a '/'. There must be another
1168 template code following the slash. See L<perlfunc/pack>.
1170 =item %s: Command not found
1172 (A) You've accidentally run your script through B<csh> instead of Perl.
1173 Check the #! line, or manually feed your script into Perl yourself.
1175 =item Compilation failed in require
1177 (F) Perl could not compile a file specified in a C<require> statement.
1178 Perl uses this generic message when none of the errors that it
1179 encountered were severe enough to halt compilation immediately.
1181 =item Complex regular subexpression recursion limit (%d) exceeded
1183 (W regexp) The regular expression engine uses recursion in complex
1184 situations where back-tracking is required. Recursion depth is limited
1185 to 32766, or perhaps less in architectures where the stack cannot grow
1186 arbitrarily. ("Simple" and "medium" situations are handled without
1187 recursion and are not subject to a limit.) Try shortening the string
1188 under examination; looping in Perl code (e.g. with C<while>) rather than
1189 in the regular expression engine; or rewriting the regular expression so
1190 that it is simpler or backtracks less. (See L<perlfaq2> for information
1191 on I<Mastering Regular Expressions>.)
1193 =item cond_broadcast() called on unlocked variable
1195 (W threads) Within a thread-enabled program, you tried to call
1196 cond_broadcast() on a variable which wasn't locked. The cond_broadcast()
1197 function is used to wake up another thread that is waiting in a
1198 cond_wait(). To ensure that the signal isn't sent before the other thread
1199 has a chance to enter the wait, it is usual for the signaling thread to
1200 first wait for a lock on variable. This lock attempt will only succeed
1201 after the other thread has entered cond_wait() and thus relinquished the
1204 =item cond_signal() called on unlocked variable
1206 (W threads) Within a thread-enabled program, you tried to call
1207 cond_signal() on a variable which wasn't locked. The cond_signal()
1208 function is used to wake up another thread that is waiting in a
1209 cond_wait(). To ensure that the signal isn't sent before the other thread
1210 has a chance to enter the wait, it is usual for the signaling thread to
1211 first wait for a lock on variable. This lock attempt will only succeed
1212 after the other thread has entered cond_wait() and thus relinquished the
1215 =item connect() on closed socket %s
1217 (W closed) You tried to do a connect on a closed socket. Did you forget
1218 to check the return value of your socket() call? See
1219 L<perlfunc/connect>.
1221 =item Constant(%s)%s: %s
1223 (F) The parser found inconsistencies either while attempting to define
1224 an overloaded constant, or when trying to find the character name
1225 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1226 corresponding C<overload> or C<charnames> pragma? See L<charnames> and
1229 =item Constant is not %s reference
1231 (F) A constant value (perhaps declared using the C<use constant> pragma)
1232 is being dereferenced, but it amounts to the wrong type of reference.
1233 The message indicates the type of reference that was expected. This
1234 usually indicates a syntax error in dereferencing the constant value.
1235 See L<perlsub/"Constant Functions"> and L<constant>.
1237 =item Constant subroutine %s redefined
1239 (S) You redefined a subroutine which had previously been
1240 eligible for inlining. See L<perlsub/"Constant Functions"> for
1241 commentary and workarounds.
1243 =item Constant subroutine %s undefined
1245 (W misc) You undefined a subroutine which had previously been eligible
1246 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1249 =item Copy method did not return a reference
1251 (F) The method which overloads "=" is buggy. See
1252 L<overload/Copy Constructor>.
1254 =item CORE::%s is not a keyword
1256 (F) The CORE:: namespace is reserved for Perl keywords.
1258 =item corrupted regexp pointers
1260 (P) The regular expression engine got confused by what the regular
1261 expression compiler gave it.
1263 =item corrupted regexp program
1265 (P) The regular expression engine got passed a regexp program without a
1268 =item Corrupt malloc ptr 0x%lx at 0x%lx
1270 (P) The malloc package that comes with Perl had an internal failure.
1272 =item Count after length/code in unpack
1274 (F) You had an unpack template indicating a counted-length string, but
1275 you have also specified an explicit size for the string. See
1278 =item Deep recursion on subroutine "%s"
1280 (W recursion) This subroutine has called itself (directly or indirectly)
1281 100 times more than it has returned. This probably indicates an
1282 infinite recursion, unless you're writing strange benchmark programs, in
1283 which case it indicates something else.
1285 =item defined(@array) is deprecated
1287 (D deprecated) defined() is not usually useful on arrays because it
1288 checks for an undefined I<scalar> value. If you want to see if the
1289 array is empty, just use C<if (@array) { # not empty }> for example.
1291 =item defined(%hash) is deprecated
1293 (D deprecated) defined() is not usually useful on hashes because it
1294 checks for an undefined I<scalar> value. If you want to see if the hash
1295 is empty, just use C<if (%hash) { # not empty }> for example.
1297 =item %s defines neither package nor VERSION--version check failed
1299 (F) You said something like "use Module 42" but in the Module file
1300 there are neither package declarations nor a C<$VERSION>.
1302 =item Delimiter for here document is too long
1304 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1305 long for Perl to handle. You have to be seriously twisted to write code
1306 that triggers this error.
1308 =item DESTROY created new reference to dead object '%s'
1310 (F) A DESTROY() method created a new reference to the object which is
1311 just being DESTROYed. Perl is confused, and prefers to abort rather than
1312 to create a dangling reference.
1314 =item Did not produce a valid header
1318 =item %s did not return a true value
1320 (F) A required (or used) file must return a true value to indicate that
1321 it compiled correctly and ran its initialization code correctly. It's
1322 traditional to end such a file with a "1;", though any true value would
1323 do. See L<perlfunc/require>.
1325 =item (Did you mean &%s instead?)
1327 (W) You probably referred to an imported subroutine &FOO as $FOO or some
1330 =item (Did you mean "local" instead of "our"?)
1332 (W misc) Remember that "our" does not localize the declared global
1333 variable. You have declared it again in the same lexical scope, which
1336 =item (Did you mean $ or @ instead of %?)
1338 (W) You probably said %hash{$key} when you meant $hash{$key} or
1339 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1344 (F) You passed die() an empty string (the equivalent of C<die "">) or
1345 you called it with no args and both C<$@> and C<$_> were empty.
1347 =item Document contains no data
1351 =item %s does not define %s::VERSION--version check failed
1353 (F) You said something like "use Module 42" but the Module did not
1354 define a C<$VERSION.>
1356 =item '/' does not take a repeat count
1358 (F) You cannot put a repeat count of any kind right after the '/' code.
1359 See L<perlfunc/pack>.
1361 =item Don't know how to handle magic of type '%s'
1363 (P) The internal handling of magical variables has been cursed.
1365 =item do_study: out of memory
1367 (P) This should have been caught by safemalloc() instead.
1369 =item (Do you need to predeclare %s?)
1371 (S syntax) This is an educated guess made in conjunction with the message
1372 "%s found where operator expected". It often means a subroutine or module
1373 name is being referenced that hasn't been declared yet. This may be
1374 because of ordering problems in your file, or because of a missing
1375 "sub", "package", "require", or "use" statement. If you're referencing
1376 something that isn't defined yet, you don't actually have to define the
1377 subroutine or package before the current location. You can use an empty
1378 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1380 =item dump() better written as CORE::dump()
1382 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1383 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1385 =item Duplicate free() ignored
1387 (S malloc) An internal routine called free() on something that had
1390 =item Duplicate modifier '%c' after '%c' in %s
1392 (W) You have applied the same modifier more than once after a type
1393 in a pack template. See L<perlfunc/pack>.
1395 =item elseif should be elsif
1397 (S syntax) There is no keyword "elseif" in Perl because Larry thinks it's
1398 ugly. Your code will be interpreted as an attempt to call a method named
1399 "elseif" for the class returned by the following block. This is
1400 unlikely to be what you want.
1404 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1405 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1406 a regular expression without specifying the property name.
1408 =item entering effective %s failed
1410 (F) While under the C<use filetest> pragma, switching the real and
1411 effective uids or gids failed.
1413 =item %ENV is aliased to %s
1415 (F) You're running under taint mode, and the C<%ENV> variable has been
1416 aliased to another hash, so it doesn't reflect anymore the state of the
1417 program's environment. This is potentially insecure.
1419 =item Error converting file specification %s
1421 (F) An error peculiar to VMS. Because Perl may have to deal with file
1422 specifications in either VMS or Unix syntax, it converts them to a
1423 single form when it must operate on them directly. Either you've passed
1424 an invalid file specification to Perl, or you've found a case the
1425 conversion routines don't handle. Drat.
1427 =item %s: Eval-group in insecure regular expression
1429 (F) Perl detected tainted data when trying to compile a regular
1430 expression that contains the C<(?{ ... })> zero-width assertion, which
1431 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1433 =item %s: Eval-group not allowed at run time
1435 (F) Perl tried to compile a regular expression containing the
1436 C<(?{ ... })> zero-width assertion at run time, as it would when the
1437 pattern contains interpolated values. Since that is a security risk, it
1438 is not allowed. If you insist, you may still do this by explicitly
1439 building the pattern from an interpolated string at run time and using
1440 that in an eval(). See L<perlre/(?{ code })>.
1442 =item %s: Eval-group not allowed, use re 'eval'
1444 (F) A regular expression contained the C<(?{ ... })> zero-width
1445 assertion, but that construct is only allowed when the C<use re 'eval'>
1446 pragma is in effect. See L<perlre/(?{ code })>.
1448 =item Excessively long <> operator
1450 (F) The contents of a <> operator may not exceed the maximum size of a
1451 Perl identifier. If you're just trying to glob a long list of
1452 filenames, try using the glob() operator, or put the filenames into a
1453 variable and glob that.
1455 =item exec? I'm not *that* kind of operating system
1457 (F) The C<exec> function is not implemented in MacPerl. See L<perlport>.
1459 =item Execution of %s aborted due to compilation errors
1461 (F) The final summary message when a Perl compilation fails.
1463 =item Exiting eval via %s
1465 (W exiting) You are exiting an eval by unconventional means, such as a
1466 goto, or a loop control statement.
1468 =item Exiting format via %s
1470 (W exiting) You are exiting a format by unconventional means, such as a
1471 goto, or a loop control statement.
1473 =item Exiting pseudo-block via %s
1475 (W exiting) You are exiting a rather special block construct (like a
1476 sort block or subroutine) by unconventional means, such as a goto, or a
1477 loop control statement. See L<perlfunc/sort>.
1479 =item Exiting subroutine via %s
1481 (W exiting) You are exiting a subroutine by unconventional means, such
1482 as a goto, or a loop control statement.
1484 =item Exiting substitution via %s
1486 (W exiting) You are exiting a substitution by unconventional means, such
1487 as a return, a goto, or a loop control statement.
1489 =item Explicit blessing to '' (assuming package main)
1491 (W misc) You are blessing a reference to a zero length string. This has
1492 the effect of blessing the reference into the package main. This is
1493 usually not what you want. Consider providing a default target package,
1494 e.g. bless($ref, $p || 'MyPackage');
1496 =item %s: Expression syntax
1498 (A) You've accidentally run your script through B<csh> instead of Perl.
1499 Check the #! line, or manually feed your script into Perl yourself.
1501 =item %s failed--call queue aborted
1503 (F) An untrapped exception was raised while executing a CHECK, INIT, or
1504 END subroutine. Processing of the remainder of the queue of such
1505 routines has been prematurely ended.
1507 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1509 (W regexp) A character class range must start and end at a literal
1510 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1511 in your false range is interpreted as a literal "-". Consider quoting the
1512 "-", "\-". The <-- HERE shows in the regular expression about where the
1513 problem was discovered. See L<perlre>.
1515 =item Fatal VMS error at %s, line %d
1517 (P) An error peculiar to VMS. Something untoward happened in a VMS
1518 system service or RTL routine; Perl's exit status should provide more
1519 details. The filename in "at %s" and the line number in "line %d" tell
1520 you which section of the Perl source code is distressed.
1522 =item fcntl is not implemented
1524 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1525 PDP-11 or something?
1527 =item Filehandle %s opened only for input
1529 (W io) You tried to write on a read-only filehandle. If you intended
1530 it to be a read-write filehandle, you needed to open it with "+<" or
1531 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1532 write the file, use ">" or ">>". See L<perlfunc/open>.
1534 =item Filehandle %s opened only for output
1536 (W io) You tried to read from a filehandle opened only for writing, If
1537 you intended it to be a read/write filehandle, you needed to open it
1538 with "+<" or "+>" or "+>>" instead of with "<" or nothing. If you
1539 intended only to read from the file, use "<". See L<perlfunc/open>.
1540 Another possibility is that you attempted to open filedescriptor 0
1541 (also known as STDIN) for output (maybe you closed STDIN earlier?).
1543 =item Filehandle %s reopened as %s only for input
1545 (W io) You opened for reading a filehandle that got the same filehandle id
1546 as STDOUT or STDERR. This occured because you closed STDOUT or STDERR
1549 =item Filehandle STDIN reopened as %s only for output
1551 (W io) You opened for writing a filehandle that got the same filehandle id
1552 as STDIN. This occured because you closed STDIN previously.
1554 =item Final $ should be \$ or $name
1556 (F) You must now decide whether the final $ in a string was meant to be
1557 a literal dollar sign, or was meant to introduce a variable name that
1558 happens to be missing. So you have to put either the backslash or the
1561 =item flock() on closed filehandle %s
1563 (W closed) The filehandle you're attempting to flock() got itself closed
1564 some time before now. Check your control flow. flock() operates on
1565 filehandles. Are you attempting to call flock() on a dirhandle by the
1568 =item Format not terminated
1570 (F) A format must be terminated by a line with a solitary dot. Perl got
1571 to the end of your file without finding such a line.
1573 =item Format %s redefined
1575 (W redefine) You redefined a format. To suppress this warning, say
1578 no warnings 'redefine';
1579 eval "format NAME =...";
1582 =item Found = in conditional, should be ==
1592 (or something like that).
1594 =item %s found where operator expected
1596 (S syntax) The Perl lexer knows whether to expect a term or an operator.
1597 If it sees what it knows to be a term when it was expecting to see an
1598 operator, it gives you this warning. Usually it indicates that an
1599 operator or delimiter was omitted, such as a semicolon.
1601 =item gdbm store returned %d, errno %d, key "%s"
1603 (S) A warning from the GDBM_File extension that a store failed.
1605 =item gethostent not implemented
1607 (F) Your C library apparently doesn't implement gethostent(), probably
1608 because if it did, it'd feel morally obligated to return every hostname
1611 =item get%sname() on closed socket %s
1613 (W closed) You tried to get a socket or peer socket name on a closed
1614 socket. Did you forget to check the return value of your socket() call?
1616 =item getpwnam returned invalid UIC %#o for user "%s"
1618 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1619 C<getpwnam> operator returned an invalid UIC.
1621 =item getsockopt() on closed socket %s
1623 (W closed) You tried to get a socket option on a closed socket. Did you
1624 forget to check the return value of your socket() call? See
1625 L<perlfunc/getsockopt>.
1627 =item Global symbol "%s" requires explicit package name
1629 (F) You've said "use strict vars", which indicates that all variables
1630 must either be lexically scoped (using "my"), declared beforehand using
1631 "our", or explicitly qualified to say which package the global variable
1634 =item glob failed (%s)
1636 (W glob) Something went wrong with the external program(s) used for
1637 C<glob> and C<< <*.c> >>. Usually, this means that you supplied a
1638 C<glob> pattern that caused the external program to fail and exit with a
1639 nonzero status. If the message indicates that the abnormal exit
1640 resulted in a coredump, this may also mean that your csh (C shell) is
1641 broken. If so, you should change all of the csh-related variables in
1642 config.sh: If you have tcsh, make the variables refer to it as if it
1643 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1644 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1645 think csh is missing. In either case, after editing config.sh, run
1646 C<./Configure -S> and rebuild Perl.
1648 =item Glob not terminated
1650 (F) The lexer saw a left angle bracket in a place where it was expecting
1651 a term, so it's looking for the corresponding right angle bracket, and
1652 not finding it. Chances are you left some needed parentheses out
1653 earlier in the line, and you really meant a "less than".
1655 =item Got an error from DosAllocMem
1657 (P) An error peculiar to OS/2. Most probably you're using an obsolete
1658 version of Perl, and this should not happen anyway.
1660 =item goto must have label
1662 (F) Unlike with "next" or "last", you're not allowed to goto an
1663 unspecified destination. See L<perlfunc/goto>.
1665 =item ()-group starts with a count
1667 (F) A ()-group started with a count. A count is
1668 supposed to follow something: a template character or a ()-group.
1669 See L<perlfunc/pack>.
1671 =item %s had compilation errors
1673 (F) The final summary message when a C<perl -c> fails.
1675 =item Had to create %s unexpectedly
1677 (S internal) A routine asked for a symbol from a symbol table that ought
1678 to have existed already, but for some reason it didn't, and had to be
1679 created on an emergency basis to prevent a core dump.
1681 =item Hash %%s missing the % in argument %d of %s()
1683 (D deprecated) Really old Perl let you omit the % on hash names in some
1684 spots. This is now heavily deprecated.
1686 =item %s has too many errors
1688 (F) The parser has given up trying to parse the program after 10 errors.
1689 Further error messages would likely be uninformative.
1691 =item Hexadecimal number > 0xffffffff non-portable
1693 (W portable) The hexadecimal number you specified is larger than 2**32-1
1694 (4294967295) and therefore non-portable between systems. See
1695 L<perlport> for more on portability concerns.
1697 =item Identifier too long
1699 (F) Perl limits identifiers (names for variables, functions, etc.) to
1700 about 250 characters for simple names, and somewhat more for compound
1701 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
1702 of Perl are likely to eliminate these arbitrary limitations.
1704 =item Illegal binary digit %s
1706 (F) You used a digit other than 0 or 1 in a binary number.
1708 =item Illegal binary digit %s ignored
1710 (W digit) You may have tried to use a digit other than 0 or 1 in a
1711 binary number. Interpretation of the binary number stopped before the
1714 =item Illegal character %s (carriage return)
1716 (F) Perl normally treats carriage returns in the program text as it
1717 would any other whitespace, which means you should never see this error
1718 when Perl was built using standard options. For some reason, your
1719 version of Perl appears to have been built without this support. Talk
1720 to your Perl administrator.
1722 =item Illegal character in prototype for %s : %s
1724 (W syntax) An illegal character was found in a prototype declaration. Legal
1725 characters in prototypes are $, @, %, *, ;, [, ], &, and \.
1727 =item Illegal declaration of anonymous subroutine
1729 (F) When using the C<sub> keyword to construct an anonymous subroutine,
1730 you must always specify a block of code. See L<perlsub>.
1732 =item Illegal declaration of subroutine %s
1734 (F) A subroutine was not declared correctly. See L<perlsub>.
1736 =item Illegal division by zero
1738 (F) You tried to divide a number by 0. Either something was wrong in
1739 your logic, or you need to put a conditional in to guard against
1742 =item Illegal hexadecimal digit %s ignored
1744 (W digit) You may have tried to use a character other than 0 - 9 or
1745 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
1746 number stopped before the illegal character.
1748 =item Illegal modulus zero
1750 (F) You tried to divide a number by 0 to get the remainder. Most
1751 numbers don't take to this kindly.
1753 =item Illegal number of bits in vec
1755 (F) The number of bits in vec() (the third argument) must be a power of
1756 two from 1 to 32 (or 64, if your platform supports that).
1758 =item Illegal octal digit %s
1760 (F) You used an 8 or 9 in an octal number.
1762 =item Illegal octal digit %s ignored
1764 (W digit) You may have tried to use an 8 or 9 in an octal number.
1765 Interpretation of the octal number stopped before the 8 or 9.
1767 =item Illegal switch in PERL5OPT: %s
1769 (X) The PERL5OPT environment variable may only be used to set the
1770 following switches: B<-[DIMUdmtw]>.
1772 =item Ill-formed CRTL environ value "%s"
1774 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
1775 internal environ array, and encountered an element without the C<=>
1776 delimiter used to separate keys from values. The element is ignored.
1778 =item Ill-formed message in prime_env_iter: |%s|
1780 (W internal) A warning peculiar to VMS. Perl tried to read a logical
1781 name or CLI symbol definition when preparing to iterate over %ENV, and
1782 didn't see the expected delimiter between key and value, so the line was
1785 =item Impossible to activate assertion call
1787 (W assertions) You're calling an assertion function in a block that is
1788 not under the control of the C<assertions> pragma.
1790 =item (in cleanup) %s
1792 (W misc) This prefix usually indicates that a DESTROY() method raised
1793 the indicated exception. Since destructors are usually called by the
1794 system at arbitrary points during execution, and often a vast number of
1795 times, the warning is issued only once for any number of failures that
1796 would otherwise result in the same message being repeated.
1798 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
1799 also result in this warning. See L<perlcall/G_KEEPERR>.
1801 =item In EBCDIC the v-string components cannot exceed 2147483647
1803 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
1804 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
1805 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
1807 =item Insecure dependency in %s
1809 (F) You tried to do something that the tainting mechanism didn't like.
1810 The tainting mechanism is turned on when you're running setuid or
1811 setgid, or when you specify B<-T> to turn it on explicitly. The
1812 tainting mechanism labels all data that's derived directly or indirectly
1813 from the user, who is considered to be unworthy of your trust. If any
1814 such data is used in a "dangerous" operation, you get this error. See
1815 L<perlsec> for more information.
1817 =item Insecure directory in %s
1819 (F) You can't use system(), exec(), or a piped open in a setuid or
1820 setgid script if C<$ENV{PATH}> contains a directory that is writable by
1821 the world. See L<perlsec>.
1823 =item Insecure $ENV{%s} while running %s
1825 (F) You can't use system(), exec(), or a piped open in a setuid or
1826 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
1827 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
1828 supplied (or potentially supplied) by the user. The script must set
1829 the path to a known value, using trustworthy data. See L<perlsec>.
1831 =item Integer overflow in %s number
1833 (W overflow) The hexadecimal, octal or binary number you have specified
1834 either as a literal or as an argument to hex() or oct() is too big for
1835 your architecture, and has been converted to a floating point number.
1836 On a 32-bit architecture the largest hexadecimal, octal or binary number
1837 representable without overflow is 0xFFFFFFFF, 037777777777, or
1838 0b11111111111111111111111111111111 respectively. Note that Perl
1839 transparently promotes all numbers to a floating point representation
1840 internally--subject to loss of precision errors in subsequent
1843 =item Integer overflow in version
1845 (F) Some portion of a version initialization is too large for the
1846 size of integers for your architecture. This is not a warning
1847 because there is no rational reason for a version to try and use a
1848 element larger than typically 2**32. This is usually caused by
1849 trying to use some odd mathematical operation as a version, like
1852 =item Internal disaster in regex; marked by <-- HERE in m/%s/
1854 (P) Something went badly wrong in the regular expression parser.
1855 The <-- HERE shows in the regular expression about where the problem was
1858 =item Internal inconsistency in tracking vforks
1860 (S) A warning peculiar to VMS. Perl keeps track of the number of times
1861 you've called C<fork> and C<exec>, to determine whether the current call
1862 to C<exec> should affect the current script or a subprocess (see
1863 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
1864 Perl is making a guess and treating this C<exec> as a request to
1865 terminate the Perl script and execute the specified command.
1867 =item Internal urp in regex; marked by <-- HERE in m/%s/
1869 (P) Something went badly awry in the regular expression parser. The
1870 <-- HERE shows in the regular expression about where the problem was
1873 =item %s (...) interpreted as function
1875 (W syntax) You've run afoul of the rule that says that any list operator
1876 followed by parentheses turns into a function, with all the list
1877 operators arguments found inside the parentheses. See
1878 L<perlop/Terms and List Operators (Leftward)>.
1880 =item Invalid %s attribute: %s
1882 The indicated attribute for a subroutine or variable was not recognized
1883 by Perl or by a user-supplied handler. See L<attributes>.
1885 =item Invalid %s attributes: %s
1887 The indicated attributes for a subroutine or variable were not
1888 recognized by Perl or by a user-supplied handler. See L<attributes>.
1890 =item Invalid conversion in %s: "%s"
1892 (W printf) Perl does not understand the given format conversion. See
1893 L<perlfunc/sprintf>.
1895 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
1897 (F) The range specified in a character class had a minimum character
1898 greater than the maximum character. One possibility is that you forgot the
1899 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
1900 up to C<ff>. The <-- HERE shows in the regular expression about where the
1901 problem was discovered. See L<perlre>.
1903 =item Invalid range "%s" in transliteration operator
1905 (F) The range specified in the tr/// or y/// operator had a minimum
1906 character greater than the maximum character. See L<perlop>.
1908 =item Invalid separator character %s in attribute list
1910 (F) Something other than a colon or whitespace was seen between the
1911 elements of an attribute list. If the previous attribute had a
1912 parenthesised parameter list, perhaps that list was terminated too soon.
1915 =item Invalid separator character %s in PerlIO layer specification %s
1917 (W layer) When pushing layers onto the Perl I/O system, something other than a
1918 colon or whitespace was seen between the elements of a layer list.
1919 If the previous attribute had a parenthesised parameter list, perhaps that
1920 list was terminated too soon.
1922 =item Invalid type '%s' in %s
1924 (F) The given character is not a valid pack or unpack type.
1925 See L<perlfunc/pack>.
1926 (W) The given character is not a valid pack or unpack type but used to be
1929 =item Invalid version format (multiple underscores)
1931 (F) Versions may contain at most a single underscore, which signals
1932 that the version is a beta release. See L<version> for the allowed
1935 =item Invalid version format (underscores before decimal)
1937 (F) Versions may not contain decimals after the optional underscore.
1938 See L<version> for the allowed version formats.
1940 =item ioctl is not implemented
1942 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1943 strange for a machine that supports C.
1945 =item ioctl() on unopened %s
1947 (W unopened) You tried ioctl() on a filehandle that was never opened.
1948 Check you control flow and number of arguments.
1950 =item IO layers (like "%s") unavailable
1952 (F) Your Perl has not been configured to have PerlIO, and therefore
1953 you cannot use IO layers. To have PerlIO Perl must be configured
1956 =item IO::Socket::atmark not implemented on this architecture
1958 (F) Your machine doesn't implement the sockatmark() functionality,
1959 neither as a system call or an ioctl call (SIOCATMARK).
1961 =item $* is no longer supported
1963 (D deprecated) The special variable C<$*>, deprecated in older perls, has
1964 been removed as of 5.9.0 and is no longer supported. You should use the
1965 C<//m> and C<//s> regexp modifiers instead.
1967 =item `%s' is not a code reference
1969 (W overload) The second (fourth, sixth, ...) argument of overload::constant
1970 needs to be a code reference. Either an anonymous subroutine, or a reference
1973 =item `%s' is not an overloadable type
1975 (W overload) You tried to overload a constant type the overload package is
1978 =item junk on end of regexp
1980 (P) The regular expression parser is confused.
1982 =item Label not found for "last %s"
1984 (F) You named a loop to break out of, but you're not currently in a loop
1985 of that name, not even if you count where you were called from. See
1988 =item Label not found for "next %s"
1990 (F) You named a loop to continue, but you're not currently in a loop of
1991 that name, not even if you count where you were called from. See
1994 =item Label not found for "redo %s"
1996 (F) You named a loop to restart, but you're not currently in a loop of
1997 that name, not even if you count where you were called from. See
2000 =item leaving effective %s failed
2002 (F) While under the C<use filetest> pragma, switching the real and
2003 effective uids or gids failed.
2005 =item length/code after end of string in unpack
2007 (F) While unpacking, the string buffer was alread used up when an unpack
2008 length/code combination tried to obtain more data. This results in
2009 an undefined value for the length. See L<perlfunc/pack>.
2011 =item listen() on closed socket %s
2013 (W closed) You tried to do a listen on a closed socket. Did you forget
2014 to check the return value of your socket() call? See
2017 =item Lookbehind longer than %d not implemented in regex; marked by <-- HERE in m/%s/
2019 (F) There is currently a limit on the length of string which lookbehind can
2020 handle. This restriction may be eased in a future release. The <-- HERE
2021 shows in the regular expression about where the problem was discovered.
2023 =item lstat() on filehandle %s
2025 (W io) You tried to do an lstat on a filehandle. What did you mean
2026 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2027 instead on the filehandle.)
2029 =item Lvalue subs returning %s not implemented yet
2031 (F) Due to limitations in the current implementation, array and hash
2032 values cannot be returned in subroutines used in lvalue context. See
2033 L<perlsub/"Lvalue subroutines">.
2035 =item Malformed integer in [] in pack
2037 (F) Between the brackets enclosing a numeric repeat count only digits
2038 are permitted. See L<perlfunc/pack>.
2040 =item Malformed integer in [] in unpack
2042 (F) Between the brackets enclosing a numeric repeat count only digits
2043 are permitted. See L<perlfunc/pack>.
2045 =item Malformed PERLLIB_PREFIX
2047 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2054 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2055 a builtin library search path, prefix2 is substituted. The error may
2056 appear if components are not found, or are too long. See
2057 "PERLLIB_PREFIX" in L<perlos2>.
2059 =item Malformed prototype for %s: %s
2061 (F) You tried to use a function with a malformed prototype. The
2062 syntax of function prototypes is given a brief compile-time check for
2063 obvious errors like invalid characters. A more rigorous check is run
2064 when the function is called.
2066 =item Malformed UTF-8 character (%s)
2068 Perl detected something that didn't comply with UTF-8 encoding rules.
2070 One possible cause is that you read in data that you thought to be in
2071 UTF-8 but it wasn't (it was for example legacy 8-bit data). Another
2072 possibility is careless use of utf8::upgrade().
2074 =item Malformed UTF-16 surrogate
2076 Perl thought it was reading UTF-16 encoded character data but while
2077 doing it Perl met a malformed Unicode surrogate.
2079 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2081 (W regexp) The pattern you've specified would be an infinite loop if the
2082 regular expression engine didn't specifically check for that. The <-- HERE
2083 shows in the regular expression about where the problem was discovered.
2086 =item "%s" may clash with future reserved word
2088 (W) This warning may be due to running a perl5 script through a perl4
2089 interpreter, especially if the word that is being warned about is
2092 =item % may not be used in pack
2094 (F) You can't pack a string by supplying a checksum, because the
2095 checksumming process loses information, and you can't go the other way.
2096 See L<perlfunc/unpack>.
2098 =item Method for operation %s not found in package %s during blessing
2100 (F) An attempt was made to specify an entry in an overloading table that
2101 doesn't resolve to a valid subroutine. See L<overload>.
2103 =item Method %s not permitted
2107 =item Might be a runaway multi-line %s string starting on line %d
2109 (S) An advisory indicating that the previous error may have been caused
2110 by a missing delimiter on a string or pattern, because it eventually
2111 ended earlier on the current line.
2113 =item Misplaced _ in number
2115 (W syntax) An underscore (underbar) in a numeric constant did not
2116 separate two digits.
2118 =item Missing %sbrace%s on \N{}
2120 (F) Wrong syntax of character name literal C<\N{charname}> within
2121 double-quotish context.
2123 =item Missing comma after first argument to %s function
2125 (F) While certain functions allow you to specify a filehandle or an
2126 "indirect object" before the argument list, this ain't one of them.
2128 =item Missing command in piped open
2130 (W pipe) You used the C<open(FH, "| command")> or
2131 C<open(FH, "command |")> construction, but the command was missing or
2134 =item Missing control char name in \c
2136 (F) A double-quoted string ended with "\c", without the required control
2139 =item Missing name in "my sub"
2141 (F) The reserved syntax for lexically scoped subroutines requires that
2142 they have a name with which they can be found.
2144 =item Missing $ on loop variable
2146 (F) Apparently you've been programming in B<csh> too much. Variables
2147 are always mentioned with the $ in Perl, unlike in the shells, where it
2148 can vary from one line to the next.
2150 =item (Missing operator before %s?)
2152 (S syntax) This is an educated guess made in conjunction with the message
2153 "%s found where operator expected". Often the missing operator is a comma.
2155 =item Missing right brace on %s
2157 (F) Missing right brace in C<\p{...}> or C<\P{...}>.
2159 =item Missing right curly or square bracket
2161 (F) The lexer counted more opening curly or square brackets than closing
2162 ones. As a general rule, you'll find it's missing near the place you
2165 =item (Missing semicolon on previous line?)
2167 (S syntax) This is an educated guess made in conjunction with the message
2168 "%s found where operator expected". Don't automatically put a semicolon on
2169 the previous line just because you saw this message.
2171 =item Modification of a read-only value attempted
2173 (F) You tried, directly or indirectly, to change the value of a
2174 constant. You didn't, of course, try "2 = 1", because the compiler
2175 catches that. But an easy way to do the same thing is:
2177 sub mod { $_[0] = 1 }
2180 Another way is to assign to a substr() that's off the end of the string.
2182 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2183 is aliased to a constant in the look I<LIST>:
2186 foreach my $n ($x, 2) {
2187 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2190 =item Modification of non-creatable array value attempted, %s
2192 (F) You tried to make an array value spring into existence, and the
2193 subscript was probably negative, even counting from end of the array
2196 =item Modification of non-creatable hash value attempted, %s
2198 (P) You tried to make a hash value spring into existence, and it
2199 couldn't be created for some peculiar reason.
2201 =item Module name must be constant
2203 (F) Only a bare module name is allowed as the first argument to a "use".
2205 =item Module name required with -%c option
2207 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2208 you omitted the name of the module. Consult L<perlrun> for full details
2209 about C<-M> and C<-m>.
2211 =item More than one argument to open
2213 (F) The C<open> function has been asked to open multiple files. This
2214 can happen if you are trying to open a pipe to a command that takes a
2215 list of arguments, but have forgotten to specify a piped open mode.
2216 See L<perlfunc/open> for details.
2218 =item msg%s not implemented
2220 (F) You don't have System V message IPC on your system.
2222 =item Multidimensional syntax %s not supported
2224 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2225 They're written like C<$foo[1][2][3]>, as in C.
2227 =item '/' must be followed by 'a*', 'A*' or 'Z*'
2229 (F) You had a pack template indicating a counted-length string,
2230 Currently the only things that can have their length counted are a*, A*
2231 or Z*. See L<perlfunc/pack>.
2233 =item '/' must follow a numeric type in unpack
2235 (F) You had an unpack template that contained a '/', but this did not
2236 follow some unpack specification producing a numeric value.
2237 See L<perlfunc/pack>.
2239 =item "my sub" not yet implemented
2241 (F) Lexically scoped subroutines are not yet implemented. Don't try
2244 =item "my" variable %s can't be in a package
2246 (F) Lexically scoped variables aren't in a package, so it doesn't make
2247 sense to try to declare one with a package qualifier on the front. Use
2248 local() if you want to localize a package variable.
2250 =item Name "%s::%s" used only once: possible typo
2252 (W once) Typographical errors often show up as unique variable names.
2253 If you had a good reason for having a unique name, then just mention it
2254 again somehow to suppress the message. The C<our> declaration is
2255 provided for this purpose.
2257 NOTE: This warning detects symbols that have been used only once so $c, @c,
2258 %c, *c, &c, sub c{}, c(), and c (the filehandle or format) are considered
2259 the same; if a program uses $c only once but also uses any of the others it
2260 will not trigger this warning.
2262 =item Negative '/' count in unpack
2264 (F) The length count obtained from a length/code unpack operation was
2265 negative. See L<perlfunc/pack>.
2267 =item Negative length
2269 (F) You tried to do a read/write/send/recv operation with a buffer
2270 length that is less than 0. This is difficult to imagine.
2272 =item Negative offset to vec in lvalue context
2274 (F) When C<vec> is called in an lvalue context, the second argument must be
2275 greater than or equal to zero.
2277 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2279 (F) You can't quantify a quantifier without intervening parentheses. So
2280 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2281 expression about where the problem was discovered.
2283 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2284 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2286 =item %s never introduced
2288 (S internal) The symbol in question was declared but somehow went out of
2289 scope before it could possibly have been used.
2291 =item Newline in left-justified string for %s
2293 (W printf) There is a newline in a string to be left justified by
2294 C<printf> or C<sprintf>.
2296 The padding spaces will appear after the newline, which is probably not
2297 what you wanted. Usually you should remove the newline from the string
2298 and put formatting characters in the C<sprintf> format.
2300 =item No %s allowed while running setuid
2302 (F) Certain operations are deemed to be too insecure for a setuid or
2303 setgid script to even be allowed to attempt. Generally speaking there
2304 will be another way to do what you want that is, if not secure, at least
2305 securable. See L<perlsec>.
2307 =item No comma allowed after %s
2309 (F) A list operator that has a filehandle or "indirect object" is not
2310 allowed to have a comma between that and the following arguments.
2311 Otherwise it'd be just another one of the arguments.
2313 One possible cause for this is that you expected to have imported a
2314 constant to your name space with B<use> or B<import> while no such
2315 importing took place, it may for example be that your operating system
2316 does not support that particular constant. Hopefully you did use an
2317 explicit import list for the constants you expect to see, please see
2318 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2319 would probably have caught this error earlier it naturally does not
2320 remedy the fact that your operating system still does not support that
2321 constant. Maybe you have a typo in the constants of the symbol import
2322 list of B<use> or B<import> or in the constant name at the line where
2323 this error was triggered?
2325 =item No command into which to pipe on command line
2327 (F) An error peculiar to VMS. Perl handles its own command line
2328 redirection, and found a '|' at the end of the command line, so it
2329 doesn't know where you want to pipe the output from this command.
2331 =item No DB::DB routine defined
2333 (F) The currently executing code was compiled with the B<-d> switch, but
2334 for some reason the perl5db.pl file (or some facsimile thereof) didn't
2335 define a routine to be called at the beginning of each statement. Which
2336 is odd, because the file should have been required automatically, and
2337 should have blown up the require if it didn't parse right.
2339 =item No dbm on this machine
2341 (P) This is counted as an internal error, because every machine should
2342 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2344 =item No DBsub routine
2346 (F) The currently executing code was compiled with the B<-d> switch,
2347 but for some reason the perl5db.pl file (or some facsimile thereof)
2348 didn't define a DB::sub routine to be called at the beginning of each
2349 ordinary subroutine call.
2351 =item No B<-e> allowed in setuid scripts
2353 (F) A setuid script can't be specified by the user.
2355 =item No error file after 2> or 2>> on command line
2357 (F) An error peculiar to VMS. Perl handles its own command line
2358 redirection, and found a '2>' or a '2>>' on the command line, but can't
2359 find the name of the file to which to write data destined for stderr.
2361 =item No group ending character '%c' found in template
2363 (F) A pack or unpack template has an opening '(' or '[' without its
2364 matching counterpart. See L<perlfunc/pack>.
2366 =item No input file after < on command line
2368 (F) An error peculiar to VMS. Perl handles its own command line
2369 redirection, and found a '<' on the command line, but can't find the
2370 name of the file from which to read data for stdin.
2374 (F) The setuid emulator requires that scripts have a well-formed #! line
2375 even on machines that don't support the #! construct.
2377 =item "no" not allowed in expression
2379 (F) The "no" keyword is recognized and executed at compile time, and
2380 returns no useful value. See L<perlmod>.
2382 =item No output file after > on command line
2384 (F) An error peculiar to VMS. Perl handles its own command line
2385 redirection, and found a lone '>' at the end of the command line, so it
2386 doesn't know where you wanted to redirect stdout.
2388 =item No output file after > or >> on command line
2390 (F) An error peculiar to VMS. Perl handles its own command line
2391 redirection, and found a '>' or a '>>' on the command line, but can't
2392 find the name of the file to which to write data destined for stdout.
2394 =item No package name allowed for variable %s in "our"
2396 (F) Fully qualified variable names are not allowed in "our"
2397 declarations, because that doesn't make much sense under existing
2398 semantics. Such syntax is reserved for future extensions.
2400 =item No Perl script found in input
2402 (F) You called C<perl -x>, but no line was found in the file beginning
2403 with #! and containing the word "perl".
2405 =item No setregid available
2407 (F) Configure didn't find anything resembling the setregid() call for
2410 =item No setreuid available
2412 (F) Configure didn't find anything resembling the setreuid() call for
2415 =item No space allowed after -%c
2417 (F) The argument to the indicated command line switch must follow
2418 immediately after the switch, without intervening spaces.
2420 =item No %s specified for -%c
2422 (F) The indicated command line switch needs a mandatory argument, but
2423 you haven't specified one.
2425 =item No such class %s
2427 (F) You provided a class qualifier in a "my" or "our" declaration, but
2428 this class doesn't exist at this point in your program.
2430 =item No such pipe open
2432 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
2433 close a pipe which hadn't been opened. This should have been caught
2434 earlier as an attempt to close an unopened filehandle.
2436 =item No such signal: SIG%s
2438 (W signal) You specified a signal name as a subscript to %SIG that was
2439 not recognized. Say C<kill -l> in your shell to see the valid signal
2440 names on your system.
2442 =item Not a CODE reference
2444 (F) Perl was trying to evaluate a reference to a code value (that is, a
2445 subroutine), but found a reference to something else instead. You can
2446 use the ref() function to find out what kind of ref it really was. See
2449 =item Not a format reference
2451 (F) I'm not sure how you managed to generate a reference to an anonymous
2452 format, but this indicates you did, and that it didn't exist.
2454 =item Not a GLOB reference
2456 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
2457 symbol table entry that looks like C<*foo>), but found a reference to
2458 something else instead. You can use the ref() function to find out what
2459 kind of ref it really was. See L<perlref>.
2461 =item Not a HASH reference
2463 (F) Perl was trying to evaluate a reference to a hash value, but found a
2464 reference to something else instead. You can use the ref() function to
2465 find out what kind of ref it really was. See L<perlref>.
2467 =item Not an ARRAY reference
2469 (F) Perl was trying to evaluate a reference to an array value, but found
2470 a reference to something else instead. You can use the ref() function
2471 to find out what kind of ref it really was. See L<perlref>.
2473 =item Not a perl script
2475 (F) The setuid emulator requires that scripts have a well-formed #! line
2476 even on machines that don't support the #! construct. The line must
2479 =item Not a SCALAR reference
2481 (F) Perl was trying to evaluate a reference to a scalar value, but found
2482 a reference to something else instead. You can use the ref() function
2483 to find out what kind of ref it really was. See L<perlref>.
2485 =item Not a subroutine reference
2487 (F) Perl was trying to evaluate a reference to a code value (that is, a
2488 subroutine), but found a reference to something else instead. You can
2489 use the ref() function to find out what kind of ref it really was. See
2492 =item Not a subroutine reference in overload table
2494 (F) An attempt was made to specify an entry in an overloading table that
2495 doesn't somehow point to a valid subroutine. See L<overload>.
2497 =item Not enough arguments for %s
2499 (F) The function requires more arguments than you specified.
2501 =item Not enough format arguments
2503 (W syntax) A format specified more picture fields than the next line
2504 supplied. See L<perlform>.
2508 (A) You've accidentally run your script through the Bourne shell instead
2509 of Perl. Check the #! line, or manually feed your script into Perl
2512 =item no UTC offset information; assuming local time is UTC
2514 (S) A warning peculiar to VMS. Perl was unable to find the local
2515 timezone offset, so it's assuming that local system time is equivalent
2516 to UTC. If it's not, define the logical name
2517 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
2518 need to be added to UTC to get local time.
2520 =item Null filename used
2522 (F) You can't require the null filename, especially because on many
2523 machines that means the current directory! See L<perlfunc/require>.
2525 =item NULL OP IN RUN
2527 (P debugging) Some internal routine called run() with a null opcode
2530 =item Null picture in formline
2532 (F) The first argument to formline must be a valid format picture
2533 specification. It was found to be empty, which probably means you
2534 supplied it an uninitialized value. See L<perlform>.
2538 (P) An attempt was made to realloc NULL.
2540 =item NULL regexp argument
2542 (P) The internal pattern matching routines blew it big time.
2544 =item NULL regexp parameter
2546 (P) The internal pattern matching routines are out of their gourd.
2548 =item Number too long
2550 (F) Perl limits the representation of decimal numbers in programs to
2551 about 250 characters. You've exceeded that length. Future
2552 versions of Perl are likely to eliminate this arbitrary limitation. In
2553 the meantime, try using scientific notation (e.g. "1e6" instead of
2556 =item Octal number in vector unsupported
2558 (F) Numbers with a leading C<0> are not currently allowed in vectors.
2559 The octal number interpretation of such numbers may be supported in a
2562 =item Octal number > 037777777777 non-portable
2564 (W portable) The octal number you specified is larger than 2**32-1
2565 (4294967295) and therefore non-portable between systems. See
2566 L<perlport> for more on portability concerns.
2568 See also L<perlport> for writing portable code.
2570 =item Odd number of arguments for overload::constant
2572 (W overload) The call to overload::constant contained an odd number of
2573 arguments. The arguments should come in pairs.
2575 =item Odd number of elements in anonymous hash
2577 (W misc) You specified an odd number of elements to initialize a hash,
2578 which is odd, because hashes come in key/value pairs.
2580 =item Odd number of elements in hash assignment
2582 (W misc) You specified an odd number of elements to initialize a hash,
2583 which is odd, because hashes come in key/value pairs.
2585 =item Offset outside string
2587 (F) You tried to do a read/write/send/recv operation with an offset
2588 pointing outside the buffer. This is difficult to imagine. The sole
2589 exception to this is that C<sysread()>ing past the buffer will extend
2590 the buffer and zero pad the new area.
2592 =item %s() on unopened %s
2594 (W unopened) An I/O operation was attempted on a filehandle that was
2595 never initialized. You need to do an open(), a sysopen(), or a socket()
2596 call, or call a constructor from the FileHandle package.
2598 =item -%s on unopened filehandle %s
2600 (W unopened) You tried to invoke a file test operator on a filehandle
2601 that isn't open. Check your control flow. See also L<perlfunc/-X>.
2605 (S internal) An internal warning that the grammar is screwed up.
2609 (S internal) An internal warning that the grammar is screwed up.
2611 =item Operation `%s': no method found, %s
2613 (F) An attempt was made to perform an overloaded operation for which no
2614 handler was defined. While some handlers can be autogenerated in terms
2615 of other handlers, there is no default handler for any operation, unless
2616 C<fallback> overloading key is specified to be true. See L<overload>.
2618 =item Operator or semicolon missing before %s
2620 (S ambiguous) You used a variable or subroutine call where the parser
2621 was expecting an operator. The parser has assumed you really meant to
2622 use an operator, but this is highly likely to be incorrect. For
2623 example, if you say "*foo *foo" it will be interpreted as if you said
2626 =item "our" variable %s redeclared
2628 (W misc) You seem to have already declared the same global once before
2629 in the current lexical scope.
2631 =item Out of memory!
2633 (X) The malloc() function returned 0, indicating there was insufficient
2634 remaining memory (or virtual memory) to satisfy the request. Perl has
2635 no option but to exit immediately.
2637 At least in Unix you may be able to get past this by increasing your
2638 process datasize limits: in csh/tcsh use C<limit> and
2639 C<limit datasize n> (where C<n> is the number of kilobytes) to check
2640 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
2641 and C<ulimit -d n>, respectively.
2643 =item Out of memory during "large" request for %s
2645 (F) The malloc() function returned 0, indicating there was insufficient
2646 remaining memory (or virtual memory) to satisfy the request. However,
2647 the request was judged large enough (compile-time default is 64K), so a
2648 possibility to shut down by trapping this error is granted.
2650 =item Out of memory during %s extend
2652 (X) An attempt was made to extend an array, a list, or a string beyond
2653 the largest possible memory allocation.
2655 =item Out of memory during request for %s
2657 (X|F) The malloc() function returned 0, indicating there was
2658 insufficient remaining memory (or virtual memory) to satisfy the
2661 The request was judged to be small, so the possibility to trap it
2662 depends on the way perl was compiled. By default it is not trappable.
2663 However, if compiled for this, Perl may use the contents of C<$^M> as an
2664 emergency pool after die()ing with this message. In this case the error
2665 is trappable I<once>, and the error message will include the line and file
2666 where the failed request happened.
2668 =item Out of memory during ridiculously large request
2670 (F) You can't allocate more than 2^31+"small amount" bytes. This error
2671 is most likely to be caused by a typo in the Perl program. e.g.,
2672 C<$arr[time]> instead of C<$arr[$time]>.
2674 =item Out of memory for yacc stack
2676 (F) The yacc parser wanted to grow its stack so it could continue
2677 parsing, but realloc() wouldn't give it more memory, virtual or
2680 =item '@' outside of string in unpack
2682 (F) You had a template that specified an absolute position outside
2683 the string being unpacked. See L<perlfunc/pack>.
2685 =item %s package attribute may clash with future reserved word: %s
2687 (W reserved) A lowercase attribute name was used that had a
2688 package-specific handler. That name might have a meaning to Perl itself
2689 some day, even though it doesn't yet. Perhaps you should use a
2690 mixed-case attribute name, instead. See L<attributes>.
2692 =item pack/unpack repeat count overflow
2694 (F) You can't specify a repeat count so large that it overflows your
2695 signed integers. See L<perlfunc/pack>.
2699 (W io) A single call to write() produced more lines than can fit on a
2700 page. See L<perlform>.
2704 (P) An internal error.
2706 =item panic: ck_grep
2708 (P) Failed an internal consistency check trying to compile a grep.
2710 =item panic: ck_split
2712 (P) Failed an internal consistency check trying to compile a split.
2714 =item panic: corrupt saved stack index
2716 (P) The savestack was requested to restore more localized values than
2717 there are in the savestack.
2719 =item panic: del_backref
2721 (P) Failed an internal consistency check while trying to reset a weak
2724 =item panic: Devel::DProf inconsistent subroutine return
2726 (P) Devel::DProf called a subroutine that exited using goto(LABEL),
2727 last(LABEL) or next(LABEL). Leaving that way a subroutine called from
2728 an XSUB will lead very probably to a crash of the interpreter. This is
2729 a bug that will hopefully one day get fixed.
2733 (P) We popped the context stack to an eval context, and then discovered
2734 it wasn't an eval context.
2736 =item panic: do_subst
2738 (P) The internal pp_subst() routine was called with invalid operational
2741 =item panic: do_trans_%s
2743 (P) The internal do_trans routines were called with invalid operational
2748 (P) The library function frexp() failed, making printf("%f") impossible.
2752 (P) We popped the context stack to a context with the specified label,
2753 and then discovered it wasn't a context we know how to do a goto in.
2755 =item panic: INTERPCASEMOD
2757 (P) The lexer got into a bad state at a case modifier.
2759 =item panic: INTERPCONCAT
2761 (P) The lexer got into a bad state parsing a string with brackets.
2763 =item panic: kid popen errno read
2765 (F) forked child returned an incomprehensible message about its errno.
2769 (P) We popped the context stack to a block context, and then discovered
2770 it wasn't a block context.
2772 =item panic: leave_scope clearsv
2774 (P) A writable lexical variable became read-only somehow within the
2777 =item panic: leave_scope inconsistency
2779 (P) The savestack probably got out of sync. At least, there was an
2780 invalid enum on the top of it.
2782 =item panic: magic_killbackrefs
2784 (P) Failed an internal consistency check while trying to reset all weak
2785 references to an object.
2789 (P) Something requested a negative number of bytes of malloc.
2791 =item panic: mapstart
2793 (P) The compiler is screwed up with respect to the map() function.
2795 =item panic: memory wrap
2797 (P) Something tried to allocate more memory than possible.
2799 =item panic: null array
2801 (P) One of the internal array routines was passed a null AV pointer.
2803 =item panic: pad_alloc
2805 (P) The compiler got confused about which scratch pad it was allocating
2806 and freeing temporaries and lexicals from.
2808 =item panic: pad_free curpad
2810 (P) The compiler got confused about which scratch pad it was allocating
2811 and freeing temporaries and lexicals from.
2813 =item panic: pad_free po
2815 (P) An invalid scratch pad offset was detected internally.
2817 =item panic: pad_reset curpad
2819 (P) The compiler got confused about which scratch pad it was allocating
2820 and freeing temporaries and lexicals from.
2822 =item panic: pad_sv po
2824 (P) An invalid scratch pad offset was detected internally.
2826 =item panic: pad_swipe curpad
2828 (P) The compiler got confused about which scratch pad it was allocating
2829 and freeing temporaries and lexicals from.
2831 =item panic: pad_swipe po
2833 (P) An invalid scratch pad offset was detected internally.
2835 =item panic: pp_iter
2837 (P) The foreach iterator got called in a non-loop context frame.
2839 =item panic: pp_match%s
2841 (P) The internal pp_match() routine was called with invalid operational
2844 =item panic: pp_split
2846 (P) Something terrible went wrong in setting up for the split.
2848 =item panic: realloc
2850 (P) Something requested a negative number of bytes of realloc.
2852 =item panic: restartop
2854 (P) Some internal routine requested a goto (or something like it), and
2855 didn't supply the destination.
2859 (P) We popped the context stack to a subroutine or eval context, and
2860 then discovered it wasn't a subroutine or eval context.
2862 =item panic: scan_num
2864 (P) scan_num() got called on something that wasn't a number.
2866 =item panic: sv_insert
2868 (P) The sv_insert() routine was told to remove more string than there
2871 =item panic: top_env
2873 (P) The compiler attempted to do a goto, or something weird like that.
2875 =item panic: utf16_to_utf8: odd bytelen
2877 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
2878 to even) byte length.
2882 (P) The lexer got into a bad state while processing a case modifier.
2884 =item Parentheses missing around "%s" list
2886 (W parenthesis) You said something like
2892 my ($foo, $bar) = @_;
2894 Remember that "my", "our", and "local" bind tighter than comma.
2896 =item C<-p> destination: %s
2898 (F) An error occurred during the implicit output invoked by the C<-p>
2899 command-line switch. (This output goes to STDOUT unless you've
2900 redirected it with select().)
2902 =item (perhaps you forgot to load "%s"?)
2904 (F) This is an educated guess made in conjunction with the message
2905 "Can't locate object method \"%s\" via package \"%s\"". It often means
2906 that a method requires a package that has not been loaded.
2908 =item Perl %s required--this is only version %s, stopped
2910 (F) The module in question uses features of a version of Perl more
2911 recent than the currently running version. How long has it been since
2912 you upgraded, anyway? See L<perlfunc/require>.
2914 =item Perl_my_%s() not available
2916 (F) Your platform has very uncommon byte-order and integer size,
2917 so it was not possible to set up some or all fixed-width byte-order
2918 conversion functions. This is only a problem when you're using the
2919 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
2921 =item PERL_SH_DIR too long
2923 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2924 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
2926 =item PERL_SIGNALS illegal: "%s"
2928 See L<perlrun/PERL_SIGNALS> for legal values.
2930 =item perl: warning: Setting locale failed.
2932 (S) The whole warning message will look something like:
2934 perl: warning: Setting locale failed.
2935 perl: warning: Please check that your locale settings:
2938 are supported and installed on your system.
2939 perl: warning: Falling back to the standard locale ("C").
2941 Exactly what were the failed locale settings varies. In the above the
2942 settings were that the LC_ALL was "En_US" and the LANG had no value.
2943 This error means that Perl detected that you and/or your operating
2944 system supplier and/or system administrator have set up the so-called
2945 locale system but Perl could not use those settings. This was not
2946 dead serious, fortunately: there is a "default locale" called "C" that
2947 Perl can and will use, the script will be run. Before you really fix
2948 the problem, however, you will get the same error message each time
2949 you run Perl. How to really fix the problem can be found in
2950 L<perllocale> section B<LOCALE PROBLEMS>.
2952 =item Permission denied
2954 (F) The setuid emulator in suidperl decided you were up to no good.
2956 =item pid %x not a child
2958 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
2959 process which isn't a subprocess of the current process. While this is
2960 fine from VMS' perspective, it's probably not what you intended.
2962 =item 'P' must have an explicit size in unpack
2964 (F) The unpack format P must have an explicit size, not "*".
2966 =item B<-P> not allowed for setuid/setgid script
2968 (F) The script would have to be opened by the C preprocessor by name,
2969 which provides a race condition that breaks security.
2971 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
2973 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
2974 shows in the regular expression about where the problem was discovered.
2975 Note that the POSIX character classes do B<not> have the C<is> prefix
2976 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
2977 not C<isprint>. See L<perlre>.
2979 =item POSIX getpgrp can't take an argument
2981 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
2982 the BSD version, which takes a pid.
2984 =item POSIX syntax [%s] belongs inside character classes in regex; marked by <-- HERE in m/%s/
2986 (W regexp) The character class constructs [: :], [= =], and [. .] go
2987 I<inside> character classes, the [] are part of the construct, for example:
2988 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
2989 implemented; they are simply placeholders for future extensions and will
2990 cause fatal errors. The <-- HERE shows in the regular expression about
2991 where the problem was discovered. See L<perlre>.
2993 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
2995 (F regexp) Within regular expression character classes ([]) the syntax
2996 beginning with "[." and ending with ".]" is reserved for future extensions.
2997 If you need to represent those character sequences inside a regular
2998 expression character class, just quote the square brackets with the
2999 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
3000 about where the problem was discovered. See L<perlre>.
3002 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3004 (F) Within regular expression character classes ([]) the syntax beginning
3005 with "[=" and ending with "=]" is reserved for future extensions. If you
3006 need to represent those character sequences inside a regular expression
3007 character class, just quote the square brackets with the backslash: "\[="
3008 and "=\]". The <-- HERE shows in the regular expression about where the
3009 problem was discovered. See L<perlre>.
3011 =item Possible attempt to put comments in qw() list
3013 (W qw) qw() lists contain items separated by whitespace; as with literal
3014 strings, comment characters are not ignored, but are instead treated as
3015 literal data. (You may have used different delimiters than the
3016 parentheses shown here; braces are also frequently used.)
3018 You probably wrote something like this:
3025 when you should have written this:
3032 If you really want comments, build your list the
3033 old-fashioned way, with quotes and commas:
3037 'b', # another comment
3040 =item Possible attempt to separate words with commas
3042 (W qw) qw() lists contain items separated by whitespace; therefore
3043 commas aren't needed to separate the items. (You may have used
3044 different delimiters than the parentheses shown here; braces are also
3047 You probably wrote something like this:
3051 which puts literal commas into some of the list items. Write it without
3052 commas if you don't want them to appear in your data:
3056 =item Possible memory corruption: %s overflowed 3rd argument
3058 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
3059 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
3060 end of the buffer just in case. This sentinel byte got clobbered, and
3061 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
3063 =item Possible precedence problem on bitwise %c operator
3065 (W precedence) Your program uses a bitwise logical operator in conjunction
3066 with a numeric comparison operator, like this :
3068 if ($x & $y == 0) { ... }
3070 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
3071 higher precedence of C<==>. This is probably not what you want. (If you
3072 really meant to write this, disable the warning, or, better, put the
3073 parentheses explicitly and write C<$x & ($y == 0)>).
3075 =item Possible unintended interpolation of %s in string
3077 (W ambiguous) You said something like `@foo' in a double-quoted string
3078 but there was no array C<@foo> in scope at the time. If you wanted a
3079 literal @foo, then write it as \@foo; otherwise find out what happened
3080 to the array you apparently lost track of.
3082 =item Possible Y2K bug: %s
3084 (W y2k) You are concatenating the number 19 with another number, which
3085 could be a potential Year 2000 problem.
3087 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
3089 (D deprecated) You have written something like this:
3093 use attrs qw(locked);
3096 You should use the new declaration syntax instead.
3102 The C<use attrs> pragma is now obsolete, and is only provided for
3103 backward-compatibility. See L<perlsub/"Subroutine Attributes">.
3105 =item Precedence problem: open %s should be open(%s)
3107 (S precedence) The old irregular construct
3111 is now misinterpreted as
3115 because of the strict regularization of Perl 5's grammar into unary and
3116 list operators. (The old open was a little of both.) You must put
3117 parentheses around the filehandle, or use the new "or" operator instead
3120 =item Premature end of script headers
3124 =item printf() on closed filehandle %s
3126 (W closed) The filehandle you're writing to got itself closed sometime
3127 before now. Check your control flow.
3129 =item print() on closed filehandle %s
3131 (W closed) The filehandle you're printing on got itself closed sometime
3132 before now. Check your control flow.
3134 =item Process terminated by SIG%s
3136 (W) This is a standard message issued by OS/2 applications, while *nix
3137 applications die in silence. It is considered a feature of the OS/2
3138 port. One can easily disable this by appropriate sighandlers, see
3139 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
3142 =item Prototype mismatch: %s vs %s
3144 (S prototype) The subroutine being declared or defined had previously been
3145 declared or defined with a different function prototype.
3147 =item Prototype not terminated
3149 (F) You've omitted the closing parenthesis in a function prototype
3152 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
3154 (F) You started a regular expression with a quantifier. Backslash it if you
3155 meant it literally. The <-- HERE shows in the regular expression about
3156 where the problem was discovered. See L<perlre>.
3158 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
3160 (F) There is currently a limit to the size of the min and max values of the
3161 {min,max} construct. The <-- HERE shows in the regular expression about where
3162 the problem was discovered. See L<perlre>.
3164 =item Quantifier unexpected on zero-length expression; marked by <-- HERE in m/%s/
3166 (W regexp) You applied a regular expression quantifier in a place where
3167 it makes no sense, such as on a zero-width assertion. Try putting the
3168 quantifier inside the assertion instead. For example, the way to match
3169 "abc" provided that it is followed by three repetitions of "xyz" is
3170 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
3172 The <-- HERE shows in the regular expression about where the problem was
3175 =item Range iterator outside integer range
3177 (F) One (or both) of the numeric arguments to the range operator ".."
3178 are outside the range which can be represented by integers internally.
3179 One possible workaround is to force Perl to use magical string increment
3180 by prepending "0" to your numbers.
3182 =item readline() on closed filehandle %s
3184 (W closed) The filehandle you're reading from got itself closed sometime
3185 before now. Check your control flow.
3187 =item read() on closed filehandle %s
3189 (W closed) You tried to read from a closed filehandle.
3191 =item read() on unopened filehandle %s
3193 (W unopened) You tried to read from a filehandle that was never opened.
3195 =item Reallocation too large: %lx
3197 (F) You can't allocate more than 64K on an MS-DOS machine.
3199 =item realloc() of freed memory ignored
3201 (S malloc) An internal routine called realloc() on something that had
3204 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3206 (F debugging) You can't use the B<-D> option unless the code to produce
3207 the desired output is compiled into Perl, which entails some overhead,
3208 which is why it's currently left out of your copy.
3210 =item Recursive inheritance detected in package '%s'
3212 (F) More than 100 levels of inheritance were used. Probably indicates
3213 an unintended loop in your inheritance hierarchy.
3215 =item Recursive inheritance detected while looking for method %s
3217 (F) More than 100 levels of inheritance were encountered while invoking
3218 a method. Probably indicates an unintended loop in your inheritance
3221 =item Reference found where even-sized list expected
3223 (W misc) You gave a single reference where Perl was expecting a list
3224 with an even number of elements (for assignment to a hash). This usually
3225 means that you used the anon hash constructor when you meant to use
3226 parens. In any case, a hash requires key/value B<pairs>.
3228 %hash = { one => 1, two => 2, }; # WRONG
3229 %hash = [ qw/ an anon array / ]; # WRONG
3230 %hash = ( one => 1, two => 2, ); # right
3231 %hash = qw( one 1 two 2 ); # also fine
3233 =item Reference is already weak
3235 (W misc) You have attempted to weaken a reference that is already weak.
3236 Doing so has no effect.
3238 =item Reference miscount in sv_replace()
3240 (W internal) The internal sv_replace() function was handed a new SV with
3241 a reference count of other than 1.
3243 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
3245 (F) You used something like C<\7> in your regular expression, but there are
3246 not at least seven sets of capturing parentheses in the expression. If you
3247 wanted to have the character with value 7 inserted into the regular expression,
3248 prepend a zero to make the number at least two digits: C<\07>
3250 The <-- HERE shows in the regular expression about where the problem was
3253 =item regexp memory corruption
3255 (P) The regular expression engine got confused by what the regular
3256 expression compiler gave it.
3258 =item Regexp out of space
3260 (P) A "can't happen" error, because safemalloc() should have caught it
3263 =item Repeated format line will never terminate (~~ and @# incompatible)
3265 (F) Your format containes the ~~ repeat-until-blank sequence and a
3266 numeric field that will never go blank so that the repetition never
3267 terminates. You might use ^# instead. See L<perlform>.
3269 =item Reversed %s= operator
3271 (W syntax) You wrote your assignment operator backwards. The = must
3272 always comes last, to avoid ambiguity with subsequent unary operators.
3274 =item Runaway format
3276 (F) Your format contained the ~~ repeat-until-blank sequence, but it
3277 produced 200 lines at once, and the 200th line looked exactly like the
3278 199th line. Apparently you didn't arrange for the arguments to exhaust
3279 themselves, either by using ^ instead of @ (for scalar variables), or by
3280 shifting or popping (for array variables). See L<perlform>.
3282 =item Scalars leaked: %d
3284 (P) Something went wrong in Perl's internal bookkeeping of scalars:
3285 not all scalar variables were deallocated by the time Perl exited.
3286 What this usually indicates is a memory leak, which is of course bad,
3287 especially if the Perl program is intended to be long-running.
3289 =item Scalar value @%s[%s] better written as $%s[%s]
3291 (W syntax) You've used an array slice (indicated by @) to select a
3292 single element of an array. Generally it's better to ask for a scalar
3293 value (indicated by $). The difference is that C<$foo[&bar]> always
3294 behaves like a scalar, both when assigning to it and when evaluating its
3295 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
3296 and provides a list context to its subscript, which can do weird things
3297 if you're expecting only one subscript.
3299 On the other hand, if you were actually hoping to treat the array
3300 element as a list, you need to look into how references work, because
3301 Perl will not magically convert between scalars and lists for you. See
3304 =item Scalar value @%s{%s} better written as $%s{%s}
3306 (W syntax) You've used a hash slice (indicated by @) to select a single
3307 element of a hash. Generally it's better to ask for a scalar value
3308 (indicated by $). The difference is that C<$foo{&bar}> always behaves
3309 like a scalar, both when assigning to it and when evaluating its
3310 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
3311 and provides a list context to its subscript, which can do weird things
3312 if you're expecting only one subscript.
3314 On the other hand, if you were actually hoping to treat the hash element
3315 as a list, you need to look into how references work, because Perl will
3316 not magically convert between scalars and lists for you. See
3319 =item Script is not setuid/setgid in suidperl
3321 (F) Oddly, the suidperl program was invoked on a script without a setuid
3322 or setgid bit set. This doesn't make much sense.
3324 =item Search pattern not terminated
3326 (F) The lexer couldn't find the final delimiter of a // or m{}
3327 construct. Remember that bracketing delimiters count nesting level.
3328 Missing the leading C<$> from a variable C<$m> may cause this error.
3330 Note that since Perl 5.9.0 a // can also be the I<defined-or>
3331 construct, not just the empty search pattern. Therefore code written
3332 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
3333 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
3335 =item %sseek() on unopened filehandle
3337 (W unopened) You tried to use the seek() or sysseek() function on a
3338 filehandle that was either never opened or has since been closed.
3340 =item select not implemented
3342 (F) This machine doesn't implement the select() system call.
3344 =item Self-ties of arrays and hashes are not supported
3346 (F) Self-ties are of arrays and hashes are not supported in
3347 the current implementation.
3349 =item Semicolon seems to be missing
3351 (W semicolon) A nearby syntax error was probably caused by a missing
3352 semicolon, or possibly some other missing operator, such as a comma.
3354 =item semi-panic: attempt to dup freed string
3356 (S internal) The internal newSVsv() routine was called to duplicate a
3357 scalar that had previously been marked as free.
3359 =item sem%s not implemented
3361 (F) You don't have System V semaphore IPC on your system.
3363 =item send() on closed socket %s
3365 (W closed) The socket you're sending to got itself closed sometime
3366 before now. Check your control flow.
3368 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
3370 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
3371 shows in the regular expression about where the problem was discovered. See
3374 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
3376 (F) A proposed regular expression extension has the character reserved but
3377 has not yet been written. The <-- HERE shows in the regular expression about
3378 where the problem was discovered. See L<perlre>.
3380 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
3382 (F) You used a regular expression extension that doesn't make sense. The
3383 <-- HERE shows in the regular expression about where the problem was
3384 discovered. See L<perlre>.
3386 =item Sequence (?#... not terminated in regex; marked by <-- HERE in m/%s/
3388 (F) A regular expression comment must be terminated by a closing
3389 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
3390 the regular expression about where the problem was discovered. See
3393 =item Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/%s/
3395 (F) If the contents of a (?{...}) clause contains braces, they must balance
3396 for Perl to properly detect the end of the clause. The <-- HERE shows in
3397 the regular expression about where the problem was discovered. See
3400 =item 500 Server error
3406 This is the error message generally seen in a browser window when trying
3407 to run a CGI program (including SSI) over the web. The actual error text
3408 varies widely from server to server. The most frequently-seen variants
3409 are "500 Server error", "Method (something) not permitted", "Document
3410 contains no data", "Premature end of script headers", and "Did not
3411 produce a valid header".
3413 B<This is a CGI error, not a Perl error>.
3415 You need to make sure your script is executable, is accessible by the
3416 user CGI is running the script under (which is probably not the user
3417 account you tested it under), does not rely on any environment variables
3418 (like PATH) from the user it isn't running under, and isn't in a
3419 location where the CGI server can't find it, basically, more or less.
3420 Please see the following for more information:
3422 http://www.perl.org/CGI_MetaFAQ.html
3423 http://www.htmlhelp.org/faq/cgifaq.html
3424 http://www.w3.org/Security/Faq/
3426 You should also look at L<perlfaq9>.
3428 =item setegid() not implemented
3430 (F) You tried to assign to C<$)>, and your operating system doesn't
3431 support the setegid() system call (or equivalent), or at least Configure
3434 =item seteuid() not implemented
3436 (F) You tried to assign to C<< $> >>, and your operating system doesn't
3437 support the seteuid() system call (or equivalent), or at least Configure
3440 =item setpgrp can't take arguments
3442 (F) Your system has the setpgrp() from BSD 4.2, which takes no
3443 arguments, unlike POSIX setpgid(), which takes a process ID and process
3446 =item setrgid() not implemented
3448 (F) You tried to assign to C<$(>, and your operating system doesn't
3449 support the setrgid() system call (or equivalent), or at least Configure
3452 =item setruid() not implemented
3454 (F) You tried to assign to C<$<>, and your operating system doesn't
3455 support the setruid() system call (or equivalent), or at least Configure
3458 =item setsockopt() on closed socket %s
3460 (W closed) You tried to set a socket option on a closed socket. Did you
3461 forget to check the return value of your socket() call? See
3462 L<perlfunc/setsockopt>.
3464 =item Setuid/gid script is writable by world
3466 (F) The setuid emulator won't run a script that is writable by the
3467 world, because the world might have written on it already.
3469 =item shm%s not implemented
3471 (F) You don't have System V shared memory IPC on your system.
3473 =item !=~ should be !~
3475 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
3476 interpreted as the != (numeric not equal) and ~ (1's complement)
3477 operators: probably not what you intended.
3479 =item <> should be quotes
3481 (F) You wrote C<< require <file> >> when you should have written
3484 =item /%s/ should probably be written as "%s"
3486 (W syntax) You have used a pattern where Perl expected to find a string,
3487 as in the first argument to C<join>. Perl will treat the true or false
3488 result of matching the pattern against $_ as the string, which is
3489 probably not what you had in mind.
3491 =item shutdown() on closed socket %s
3493 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
3496 =item SIG%s handler "%s" not defined
3498 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
3499 Perhaps you put it into the wrong package?
3501 =item sort is now a reserved word
3503 (F) An ancient error message that almost nobody ever runs into anymore.
3504 But before sort was a keyword, people sometimes used it as a filehandle.
3506 =item Sort subroutine didn't return a numeric value
3508 (F) A sort comparison routine must return a number. You probably blew
3509 it by not using C<< <=> >> or C<cmp>, or by not using them correctly.
3510 See L<perlfunc/sort>.
3512 =item Sort subroutine didn't return single value
3514 (F) A sort comparison subroutine may not return a list value with more
3515 or less than one element. See L<perlfunc/sort>.
3517 =item splice() offset past end of array
3519 (W misc) You attempted to specify an offset that was past the end of
3520 the array passed to splice(). Splicing will instead commence at the end
3521 of the array, rather than past it. If this isn't what you want, try
3522 explicitly pre-extending the array by assigning $#array = $offset. See
3527 (P) The split was looping infinitely. (Obviously, a split shouldn't
3528 iterate more times than there are characters of input, which is what
3529 happened.) See L<perlfunc/split>.
3531 =item Statement unlikely to be reached
3533 (W exec) You did an exec() with some statement after it other than a
3534 die(). This is almost always an error, because exec() never returns
3535 unless there was a failure. You probably wanted to use system()
3536 instead, which does return. To suppress this warning, put the exec() in
3539 =item stat() on unopened filehandle %s
3541 (W unopened) You tried to use the stat() function on a filehandle that
3542 was either never opened or has since been closed.
3544 =item Stub found while resolving method `%s' overloading %s
3546 (P) Overloading resolution over @ISA tree may be broken by importation
3547 stubs. Stubs should never be implicitly created, but explicit calls to
3548 C<can> may break this.
3550 =item Subroutine %s redefined
3552 (W redefine) You redefined a subroutine. To suppress this warning, say
3555 no warnings 'redefine';
3556 eval "sub name { ... }";
3559 =item Substitution loop
3561 (P) The substitution was looping infinitely. (Obviously, a substitution
3562 shouldn't iterate more times than there are characters of input, which
3563 is what happened.) See the discussion of substitution in
3564 L<perlop/"Quote and Quote-like Operators">.
3566 =item Substitution pattern not terminated
3568 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
3569 construct. Remember that bracketing delimiters count nesting level.
3570 Missing the leading C<$> from variable C<$s> may cause this error.
3572 =item Substitution replacement not terminated
3574 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
3575 construct. Remember that bracketing delimiters count nesting level.
3576 Missing the leading C<$> from variable C<$s> may cause this error.
3578 =item substr outside of string
3580 (W substr),(F) You tried to reference a substr() that pointed outside of
3581 a string. That is, the absolute value of the offset was larger than the
3582 length of the string. See L<perlfunc/substr>. This warning is fatal if
3583 substr is used in an lvalue context (as the left hand side of an
3584 assignment or as a subroutine argument for example).
3586 =item suidperl is no longer needed since %s
3588 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but
3589 a version of the setuid emulator somehow got run anyway.
3591 =item Switch (?(condition)... contains too many branches in regex; marked by <-- HERE in m/%s/
3593 (F) A (?(condition)if-clause|else-clause) construct can have at most two
3594 branches (the if-clause and the else-clause). If you want one or both to
3595 contain alternation, such as using C<this|that|other>, enclose it in
3596 clustering parentheses:
3598 (?(condition)(?:this|that|other)|else-clause)
3600 The <-- HERE shows in the regular expression about where the problem was
3601 discovered. See L<perlre>.
3603 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
3605 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
3606 number, it can be only a number. The <-- HERE shows in the regular expression
3607 about where the problem was discovered. See L<perlre>.
3609 =item switching effective %s is not implemented
3611 (F) While under the C<use filetest> pragma, we cannot switch the real
3612 and effective uids or gids.
3616 (F) The final summary message when a C<perl -c> succeeds.
3620 (F) Probably means you had a syntax error. Common reasons include:
3622 A keyword is misspelled.
3623 A semicolon is missing.
3625 An opening or closing parenthesis is missing.
3626 An opening or closing brace is missing.
3627 A closing quote is missing.
3629 Often there will be another error message associated with the syntax
3630 error giving more information. (Sometimes it helps to turn on B<-w>.)
3631 The error message itself often tells you where it was in the line when
3632 it decided to give up. Sometimes the actual error is several tokens
3633 before this, because Perl is good at understanding random input.
3634 Occasionally the line number may be misleading, and once in a blue moon
3635 the only way to figure out what's triggering the error is to call
3636 C<perl -c> repeatedly, chopping away half the program each time to see
3637 if the error went away. Sort of the cybernetic version of S<20
3640 =item syntax error at line %d: `%s' unexpected
3642 (A) You've accidentally run your script through the Bourne shell instead
3643 of Perl. Check the #! line, or manually feed your script into Perl
3646 =item syntax error in file %s at line %d, next 2 tokens "%s"
3648 (F) This error is likely to occur if you run a perl5 script through
3649 a perl4 interpreter, especially if the next 2 tokens are "use strict"
3650 or "my $var" or "our $var".
3652 =item sysread() on closed filehandle %s
3654 (W closed) You tried to read from a closed filehandle.
3656 =item sysread() on unopened filehandle %s
3658 (W unopened) You tried to read from a filehandle that was never opened.
3660 =item System V %s is not implemented on this machine
3662 (F) You tried to do something with a function beginning with "sem",
3663 "shm", or "msg" but that System V IPC is not implemented in your
3664 machine. In some machines the functionality can exist but be
3665 unconfigured. Consult your system support.
3667 =item syswrite() on closed filehandle %s
3669 (W closed) The filehandle you're writing to got itself closed sometime
3670 before now. Check your control flow.
3672 =item C<-T> and C<-B> not implemented on filehandles
3674 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
3675 know about your kind of stdio. You'll have to use a filename instead.
3677 =item Target of goto is too deeply nested
3679 (F) You tried to use C<goto> to reach a label that was too deeply nested
3680 for Perl to reach. Perl is doing you a favor by refusing.
3682 =item tell() on unopened filehandle
3684 (W unopened) You tried to use the tell() function on a filehandle that
3685 was either never opened or has since been closed.
3687 =item That use of $[ is unsupported
3689 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
3690 as a compiler directive. You may say only one of
3699 This is to prevent the problem of one module changing the array base out
3700 from under another module inadvertently. See L<perlvar/$[>.
3702 =item The crypt() function is unimplemented due to excessive paranoia
3704 (F) Configure couldn't find the crypt() function on your machine,
3705 probably because your vendor didn't supply it, probably because they
3706 think the U.S. Government thinks it's a secret, or at least that they
3707 will continue to pretend that it is. And if you quote me on that, I
3710 =item The %s function is unimplemented
3712 The function indicated isn't implemented on this architecture, according
3713 to the probings of Configure.
3715 =item The stat preceding %s wasn't an lstat
3717 (F) It makes no sense to test the current stat buffer for symbolic
3718 linkhood if the last stat that wrote to the stat buffer already went
3719 past the symlink to get to the real file. Use an actual filename
3722 =item The 'unique' attribute may only be applied to 'our' variables
3724 (F) Currently this attribute is not supported on C<my> or C<sub>
3725 declarations. See L<perlfunc/our>.
3727 =item This Perl can't reset CRTL environ elements (%s)
3729 =item This Perl can't set CRTL environ elements (%s=%s)
3731 (W internal) Warnings peculiar to VMS. You tried to change or delete an
3732 element of the CRTL's internal environ array, but your copy of Perl
3733 wasn't built with a CRTL that contained the setenv() function. You'll
3734 need to rebuild Perl with a CRTL that does, or redefine
3735 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
3736 target of the change to
3737 %ENV which produced the warning.
3739 =item thread failed to start: %s
3741 (F) The entry point function of threads->create() failed for some reason.
3743 =item times not implemented
3745 (F) Your version of the C library apparently doesn't do times(). I
3746 suspect you're not running on Unix.
3748 =item To%s: illegal mapping '%s'
3750 (F) You tried to define a customized To-mapping for lc(), lcfirst,
3751 uc(), or ucfirst() (or their string-inlined versions), but you
3752 specified an illegal mapping.
3753 See L<perlunicode/"User-Defined Character Properties">.
3755 =item Too deeply nested ()-groups
3757 (F) Your template contains ()-groups with a ridiculously deep nesting level.
3759 =item Too few args to syscall
3761 (F) There has to be at least one argument to syscall() to specify the
3762 system call to call, silly dilly.
3764 =item Too late for "-%s" option
3766 (X) The #! line (or local equivalent) in a Perl script contains the
3767 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
3768 are not intended for use inside scripts. Use the C<use> pragma instead.
3770 =item Too late for "B<-T>" option
3772 (X) The #! line (or local equivalent) in a Perl script contains the
3773 B<-T> option, but Perl was not invoked with B<-T> in its command line.
3774 This is an error because, by the time Perl discovers a B<-T> in a
3775 script, it's too late to properly taint everything from the environment.
3778 If the Perl script is being executed as a command using the #!
3779 mechanism (or its local equivalent), this error can usually be fixed by
3780 editing the #! line so that the B<-T> option is a part of Perl's first
3781 argument: e.g. change C<perl -n -T> to C<perl -T -n>.
3783 If the Perl script is being executed as C<perl scriptname>, then the
3784 B<-T> option must appear on the command line: C<perl -T scriptname>.
3786 =item Too late to run %s block
3788 (W void) A CHECK or INIT block is being defined during run time proper,
3789 when the opportunity to run them has already passed. Perhaps you are
3790 loading a file with C<require> or C<do> when you should be using C<use>
3791 instead. Or perhaps you should put the C<require> or C<do> inside a
3794 =item Too many args to syscall
3796 (F) Perl supports a maximum of only 14 args to syscall().
3798 =item Too many arguments for %s
3800 (F) The function requires fewer arguments than you specified.
3804 (A) You've accidentally run your script through B<csh> instead of Perl.
3805 Check the #! line, or manually feed your script into Perl yourself.
3809 (A) You've accidentally run your script through B<csh> instead of Perl.
3810 Check the #! line, or manually feed your script into Perl yourself.
3812 =item Trailing \ in regex m/%s/
3814 (F) The regular expression ends with an unbackslashed backslash.
3815 Backslash it. See L<perlre>.
3817 =item Transliteration pattern not terminated
3819 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
3820 or y/// or y[][] construct. Missing the leading C<$> from variables
3821 C<$tr> or C<$y> may cause this error.
3823 =item Transliteration replacement not terminated
3825 (F) The lexer couldn't find the final delimiter of a tr///, tr[][],
3826 y/// or y[][] construct.
3828 =item '%s' trapped by operation mask
3830 (F) You tried to use an operator from a Safe compartment in which it's
3831 disallowed. See L<Safe>.
3833 =item truncate not implemented
3835 (F) Your machine doesn't implement a file truncation mechanism that
3836 Configure knows about.
3838 =item Type of arg %d to %s must be %s (not %s)
3840 (F) This function requires the argument in that position to be of a
3841 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
3842 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
3843 {EXPR} forms as an explicit dereference. See L<perlref>.
3845 =item umask not implemented
3847 (F) Your machine doesn't implement the umask function and you tried to
3848 use it to restrict permissions for yourself (EXPR & 0700).
3850 =item Unable to create sub named "%s"
3852 (F) You attempted to create or access a subroutine with an illegal name.
3854 =item Unbalanced context: %d more PUSHes than POPs
3856 (W internal) The exit code detected an internal inconsistency in how
3857 many execution contexts were entered and left.
3859 =item Unbalanced saves: %d more saves than restores
3861 (W internal) The exit code detected an internal inconsistency in how
3862 many values were temporarily localized.
3864 =item Unbalanced scopes: %d more ENTERs than LEAVEs
3866 (W internal) The exit code detected an internal inconsistency in how
3867 many blocks were entered and left.
3869 =item Unbalanced tmps: %d more allocs than frees
3871 (W internal) The exit code detected an internal inconsistency in how
3872 many mortal scalars were allocated and freed.
3874 =item Undefined format "%s" called
3876 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3877 another package? See L<perlform>.
3879 =item Undefined sort subroutine "%s" called
3881 (F) The sort comparison routine specified doesn't seem to exist.
3882 Perhaps it's in a different package? See L<perlfunc/sort>.
3884 =item Undefined subroutine &%s called
3886 (F) The subroutine indicated hasn't been defined, or if it was, it has
3887 since been undefined.
3889 =item Undefined subroutine called
3891 (F) The anonymous subroutine you're trying to call hasn't been defined,
3892 or if it was, it has since been undefined.
3894 =item Undefined subroutine in sort
3896 (F) The sort comparison routine specified is declared but doesn't seem
3897 to have been defined yet. See L<perlfunc/sort>.
3899 =item Undefined top format "%s" called
3901 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3902 another package? See L<perlform>.
3904 =item Undefined value assigned to typeglob
3906 (W misc) An undefined value was assigned to a typeglob, a la
3907 C<*foo = undef>. This does nothing. It's possible that you really mean
3910 =item %s: Undefined variable
3912 (A) You've accidentally run your script through B<csh> instead of Perl.
3913 Check the #! line, or manually feed your script into Perl yourself.
3915 =item unexec of %s into %s failed!
3917 (F) The unexec() routine failed for some reason. See your local FSF
3918 representative, who probably put it there in the first place.
3920 =item Unicode character %s is illegal
3922 (W utf8) Certain Unicode characters have been designated off-limits by
3923 the Unicode standard and should not be generated. If you really know
3924 what you are doing you can turn off this warning by C<no warnings 'utf8';>.
3926 =item Unknown BYTEORDER
3928 (F) There are no byte-swapping functions for a machine with this byte
3931 =item Unknown open() mode '%s'
3933 (F) The second argument of 3-argument open() is not among the list
3934 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
3935 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
3937 =item Unknown PerlIO layer "%s"
3939 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
3940 system. (Layers take care of transforming data between external and
3941 internal representations.) Note that some layers, such as C<mmap>,
3942 are not supported in all environments. If your program didn't
3943 explicitly request the failing operation, it may be the result of the
3944 value of the environment variable PERLIO.
3946 =item Unknown process %x sent message to prime_env_iter: %s
3948 (P) An error peculiar to VMS. Perl was reading values for %ENV before
3949 iterating over it, and someone else stuck a message in the stream of
3950 data Perl expected. Someone's very confused, or perhaps trying to
3951 subvert Perl's population of %ENV for nefarious purposes.
3953 =item Unknown "re" subpragma '%s' (known ones are: %s)
3955 You tried to use an unknown subpragma of the "re" pragma.
3957 =item Unknown switch condition (?(%.2s in regex; marked by <-- HERE in m/%s/
3959 (F) The condition part of a (?(condition)if-clause|else-clause) construct
3960 is not known. The condition may be lookahead or lookbehind (the condition
3961 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
3962 condition is true if the code evaluates to a true value), or a number (the
3963 condition is true if the set of capturing parentheses named by the number
3966 The <-- HERE shows in the regular expression about where the problem was
3967 discovered. See L<perlre>.
3969 =item Unknown Unicode option letter '%c'
3971 You specified an unknown Unicode option. See L<perlrun> documentation
3972 of the C<-C> switch for the list of known options.
3974 =item Unknown Unicode option value %x
3976 You specified an unknown Unicode option. See L<perlrun> documentation
3977 of the C<-C> switch for the list of known options.
3979 =item Unknown warnings category '%s'
3981 (F) An error issued by the C<warnings> pragma. You specified a warnings
3982 category that is unknown to perl at this point.
3984 Note that if you want to enable a warnings category registered by a module
3985 (e.g. C<use warnings 'File::Find'>), you must have imported this module
3988 =item unmatched [ in regex; marked by <-- HERE in m/%s/
3990 (F) The brackets around a character class must match. If you wish to
3991 include a closing bracket in a character class, backslash it or put it
3992 first. The <-- HERE shows in the regular expression about where the problem
3993 was discovered. See L<perlre>.
3995 =item unmatched ( in regex; marked by <-- HERE in m/%s/
3997 (F) Unbackslashed parentheses must always be balanced in regular
3998 expressions. If you're a vi user, the % key is valuable for finding the
3999 matching parenthesis. The <-- HERE shows in the regular expression about
4000 where the problem was discovered. See L<perlre>.
4002 =item Unmatched right %s bracket
4004 (F) The lexer counted more closing curly or square brackets than opening
4005 ones, so you're probably missing a matching opening bracket. As a
4006 general rule, you'll find the missing one (so to speak) near the place
4007 you were last editing.
4009 =item Unquoted string "%s" may clash with future reserved word
4011 (W reserved) You used a bareword that might someday be claimed as a
4012 reserved word. It's best to put such a word in quotes, or capitalize it
4013 somehow, or insert an underbar into it. You might also declare it as a
4016 =item Unrecognized character %s
4018 (F) The Perl parser has no idea what to do with the specified character
4019 in your Perl script (or eval). Perhaps you tried to run a compressed
4020 script, a binary program, or a directory as a Perl program.
4022 =item /%s/: Unrecognized escape \\%c in character class passed through
4024 (W regexp) You used a backslash-character combination which is not
4025 recognized by Perl inside character classes. The character was
4026 understood literally.
4028 =item Unrecognized escape \\%c passed through
4030 (W misc) You used a backslash-character combination which is not
4033 =item Unrecognized escape \\%c passed through in regex; marked by <-- HERE in m/%s/
4035 (W regexp) You used a backslash-character combination which is not
4036 recognized by Perl. This combination appears in an interpolated variable or
4037 a C<'>-delimited regular expression. The character was understood
4038 literally. The <-- HERE shows in the regular expression about where the
4039 escape was discovered.
4041 =item Unrecognized signal name "%s"
4043 (F) You specified a signal name to the kill() function that was not
4044 recognized. Say C<kill -l> in your shell to see the valid signal names
4047 =item Unrecognized switch: -%s (-h will show valid options)
4049 (F) You specified an illegal option to Perl. Don't do that. (If you
4050 think you didn't do that, check the #! line to see if it's supplying the
4051 bad switch on your behalf.)
4053 =item Unsuccessful %s on filename containing newline
4055 (W newline) A file operation was attempted on a filename, and that
4056 operation failed, PROBABLY because the filename contained a newline,
4057 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
4059 =item Unsupported directory function "%s" called
4061 (F) Your machine doesn't support opendir() and readdir().
4063 =item Unsupported function %s
4065 (F) This machine doesn't implement the indicated function, apparently.
4066 At least, Configure doesn't think so.
4068 =item Unsupported function fork
4070 (F) Your version of executable does not support forking.
4072 Note that under some systems, like OS/2, there may be different flavors
4073 of Perl executables, some of which may support fork, some not. Try
4074 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
4076 =item Unsupported script encoding %s
4078 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
4079 declares it to be in a Unicode encoding that Perl cannot read.
4081 =item Unsupported socket function "%s" called
4083 (F) Your machine doesn't support the Berkeley socket mechanism, or at
4084 least that's what Configure thought.
4086 =item Unterminated attribute list
4088 (F) The lexer found something other than a simple identifier at the
4089 start of an attribute, and it wasn't a semicolon or the start of a
4090 block. Perhaps you terminated the parameter list of the previous
4091 attribute too soon. See L<attributes>.
4093 =item Unterminated attribute parameter in attribute list
4095 (F) The lexer saw an opening (left) parenthesis character while parsing
4096 an attribute list, but the matching closing (right) parenthesis
4097 character was not found. You may need to add (or remove) a backslash
4098 character to get your parentheses to balance. See L<attributes>.
4100 =item Unterminated compressed integer
4102 (F) An argument to unpack("w",...) was incompatible with the BER
4103 compressed integer format and could not be converted to an integer.
4104 See L<perlfunc/pack>.
4106 =item Unterminated <> operator
4108 (F) The lexer saw a left angle bracket in a place where it was expecting
4109 a term, so it's looking for the corresponding right angle bracket, and
4110 not finding it. Chances are you left some needed parentheses out
4111 earlier in the line, and you really meant a "less than".
4113 =item untie attempted while %d inner references still exist
4115 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
4116 still valid when C<untie> was called.
4118 =item Usage: POSIX::%s(%s)
4120 (F) You called a POSIX function with incorrect arguments.
4121 See L<POSIX/FUNCTIONS> for more information.
4123 =item Usage: Win32::%s(%s)
4125 (F) You called a Win32 function with incorrect arguments.
4126 See L<Win32> for more information.
4128 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in m/%s/
4130 (W regexp) You have used an internal modifier such as (?-o) that has no
4131 meaning unless removed from the entire regexp:
4133 if ($string =~ /(?-o)$pattern/o) { ... }
4137 if ($string =~ /$pattern/) { ... }
4139 The <-- HERE shows in the regular expression about
4140 where the problem was discovered. See L<perlre>.
4142 =item Useless localization of %s
4144 (W syntax) The localization of lvalues such as C<local($x=10)> is
4145 legal, but in fact the local() currently has no effect. This may change at
4146 some point in the future, but in the meantime such code is discouraged.
4148 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
4150 (W regexp) You have used an internal modifier such as (?o) that has no
4151 meaning unless applied to the entire regexp:
4153 if ($string =~ /(?o)$pattern/) { ... }
4157 if ($string =~ /$pattern/o) { ... }
4159 The <-- HERE shows in the regular expression about
4160 where the problem was discovered. See L<perlre>.
4162 =item Useless use of %s in void context
4164 (W void) You did something without a side effect in a context that does
4165 nothing with the return value, such as a statement that doesn't return a
4166 value from a block, or the left side of a scalar comma operator. Very
4167 often this points not to stupidity on your part, but a failure of Perl
4168 to parse your program the way you thought it would. For example, you'd
4169 get this if you mixed up your C precedence with Python precedence and
4174 when you meant to say
4176 ($one, $two) = (1, 2);
4178 Another common error is to use ordinary parentheses to construct a list
4179 reference when you should be using square or curly brackets, for
4184 when you should have said
4188 The square brackets explicitly turn a list value into a scalar value,
4189 while parentheses do not. So when a parenthesized list is evaluated in
4190 a scalar context, the comma is treated like C's comma operator, which
4191 throws away the left argument, which is not what you want. See
4192 L<perlref> for more on this.
4194 This warning will not be issued for numerical constants equal to 0 or 1
4195 since they are often used in statements like
4197 1 while sub_with_side_effects() ;
4199 String constants that would normally evaluate to 0 or 1 are warned
4202 =item Useless use of "re" pragma
4204 (W) You did C<use re;> without any arguments. That isn't very useful.
4206 =item Useless use of sort in scalar context
4208 (W void) You used sort in scalar context, as in :
4212 This is not very useful, and perl currently optimizes this away.
4214 =item Useless use of %s with no values
4216 (W syntax) You used the push() or unshift() function with no arguments
4217 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
4218 usually have any effect on the array, so is completely useless. It's
4219 possible in principle that push(@tied_array) could have some effect
4220 if the array is tied to a class which implements a PUSH method. If so,
4221 you can write it as C<push(@tied_array,())> to avoid this warning.
4223 =item "use" not allowed in expression
4225 (F) The "use" keyword is recognized and executed at compile time, and
4226 returns no useful value. See L<perlmod>.
4228 =item Use of bare << to mean <<"" is deprecated
4230 (D deprecated) You are now encouraged to use the explicitly quoted form
4231 if you wish to use an empty line as the terminator of the here-document.
4233 =item Use of chdir('') or chdir(undef) as chdir() deprecated
4235 (D deprecated) chdir() with no arguments is documented to change to
4236 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
4237 behavior, but that has been deprecated. In future versions they
4240 Be careful to check that what you pass to chdir() is defined and not
4241 blank, else you might find yourself in your home directory.
4243 =item Use of /c modifier is meaningless in s///
4245 (W regexp) You used the /c modifier in a substitution. The /c
4246 modifier is not presently meaningful in substitutions.
4248 =item Use of /c modifier is meaningless without /g
4250 (W regexp) You used the /c modifier with a regex operand, but didn't
4251 use the /g modifier. Currently, /c is meaningful only when /g is
4252 used. (This may change in the future.)
4254 =item Use of freed value in iteration
4256 (F) Perhaps you modified the iterated array within the loop?
4257 This error is typically caused by code like the following:
4260 @a = () for (1,2,@a);
4262 You are not supposed to modify arrays while they are being iterated over.
4263 For speed and efficiency reasons, Perl internally does not do full
4264 reference-counting of iterated items, hence deleting such an item in the
4265 middle of an iteration causes Perl to see a freed value.
4267 =item Use of *glob{FILEHANDLE} is deprecated
4269 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
4270 to access the filehandle slot within a typeglob.
4272 =item Use of /g modifier is meaningless in split
4274 (W regexp) You used the /g modifier on the pattern for a C<split>
4275 operator. Since C<split> always tries to match the pattern
4276 repeatedly, the C</g> has no effect.
4278 =item Use of implicit split to @_ is deprecated
4280 (D deprecated) It makes a lot of work for the compiler when you clobber
4281 a subroutine's argument list, so it's better if you assign the results
4282 of a split() explicitly to an array (or list).
4284 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
4286 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
4287 are looked up as methods (using the C<@ISA> hierarchy) even when the
4288 subroutines to be autoloaded were called as plain functions (e.g.
4289 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
4292 This bug will be rectified in future by using method lookup only for
4293 methods' C<AUTOLOAD>s. However, there is a significant base of existing
4294 code that may be using the old behavior. So, as an interim step, Perl
4295 currently issues an optional warning when non-methods use inherited
4298 The simple rule is: Inheritance will not work when autoloading
4299 non-methods. The simple fix for old code is: In any module that used
4300 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
4301 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
4304 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
4305 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
4306 C<use AutoLoader 'AUTOLOAD';>.
4308 =item Use of %s in printf format not supported
4310 (F) You attempted to use a feature of printf that is accessible from
4311 only C. This usually means there's a better way to do it in Perl.
4313 =item Use of $# is deprecated
4315 (D deprecated) This was an ill-advised attempt to emulate a poorly
4316 defined B<awk> feature. Use an explicit printf() or sprintf() instead.
4318 =item Use of %s is deprecated
4320 (D deprecated) The construct indicated is no longer recommended for use,
4321 generally because there's a better way to do it, and also because the
4322 old way has bad side effects.
4324 =item Use of -l on filehandle %s
4326 (W io) A filehandle represents an opened file, and when you opened the file
4327 it already went past any symlink you are presumably trying to look for.
4328 The operation returned C<undef>. Use a filename instead.
4330 =item Deprecated use of my() in false conditional
4332 (D deprecated) You used a declaration similar to C<my $x if 0>.
4333 There has been a long-standing bug in Perl that causes a lexical variable
4334 not to be cleared at scope exit when its declaration includes a false
4335 conditional. Some people have exploited this bug to achieve a kind of
4336 static variable. Since we intend to fix this bug, we don't want people
4337 relying on this behavior. You can achieve a similar static effect by
4338 declaring the variable in a separate block outside the function, eg
4340 sub f { my $x if 0; return $x++ }
4344 { my $x; sub f { return $x++ } }
4346 =item Use of "package" with no arguments is deprecated
4348 (D deprecated) You used the C<package> keyword without specifying a package
4349 name. So no namespace is current at all. Using this can cause many
4350 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
4353 =item Use of reference "%s" as array index
4355 (W misc) You tried to use a reference as an array index; this probably
4356 isn't what you mean, because references in numerical context tend
4357 to be huge numbers, and so usually indicates programmer error.
4359 If you really do mean it, explicitly numify your reference, like so:
4360 C<$array[0+$ref]>. This warning is not given for overloaded objects,
4361 either, because you can overload the numification and stringification
4362 operators and then you assumedly know what you are doing.
4364 =item Use of reserved word "%s" is deprecated
4366 (D deprecated) The indicated bareword is a reserved word. Future
4367 versions of perl may use it as a keyword, so you're better off either
4368 explicitly quoting the word in a manner appropriate for its context of
4369 use, or using a different name altogether. The warning can be
4370 suppressed for subroutine names by either adding a C<&> prefix, or using
4371 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
4373 =item Use of tainted arguments in %s is deprecated
4375 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
4376 arguments and at least one of them is tainted. This used to be allowed
4377 but will become a fatal error in a future version of perl. Untaint your
4378 arguments. See L<perlsec>.
4380 =item Use of uninitialized value%s
4382 (W uninitialized) An undefined value was used as if it were already
4383 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
4384 To suppress this warning assign a defined value to your variables.
4386 To help you figure out what was undefined, perl will try to tell you the
4387 name of the variable (if any) that was undefined. In some cases it cannot
4388 do this, so it also tells you what operation you used the undefined value
4389 in. Note, however, that perl optimizes your program and the operation
4390 displayed in the warning may not necessarily appear literally in your
4391 program. For example, C<"that $foo"> is usually optimized into C<"that "
4392 . $foo>, and the warning will refer to the C<concatenation (.)> operator,
4393 even though there is no C<.> in your program.
4395 =item Using a hash as a reference is deprecated
4397 (D deprecated) You tried to use a hash as a reference, as in
4398 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
4399 used to allow this syntax, but shouldn't have. It is now deprecated, and will
4400 be removed in a future version.
4402 =item Using an array as a reference is deprecated
4404 (D deprecated) You tried to use an array as a reference, as in
4405 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
4406 allow this syntax, but shouldn't have. It is now deprecated, and will be
4407 removed in a future version.
4409 =item UTF-16 surrogate %s
4411 (W utf8) You tried to generate half of an UTF-16 surrogate by
4412 requesting a Unicode character between the code points 0xD800 and
4413 0xDFFF (inclusive). That range is reserved exclusively for the use of
4414 UTF-16 encoding (by having two 16-bit UCS-2 characters); but Perl
4415 encodes its characters in UTF-8, so what you got is a very illegal
4416 character. If you really know what you are doing you can turn off
4417 this warning by C<no warnings 'utf8';>.
4419 =item Value of %s can be "0"; test with defined()
4421 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
4422 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
4423 can return a value of "0"; that would make the conditional expression
4424 false, which is probably not what you intended. When using these
4425 constructs in conditional expressions, test their values with the
4426 C<defined> operator.
4428 =item Value of CLI symbol "%s" too long
4430 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
4431 %ENV element from a CLI symbol table, and found a resultant string
4432 longer than 1024 characters. The return value has been truncated to
4435 =item Variable "%s" is not available
4437 (W closure) During compilation, an inner named subroutine or eval is
4438 attempting to capture an outer lexical that is not currently available.
4439 This can happen for one of two reasons. First, the outer lexical may be
4440 declared in an outer anonymous subroutine that has not yet been created.
4441 (Remember that named subs are created at compile time, while anonymous
4442 subs are created at run-time.) For example,
4444 sub { my $a; sub f { $a } }
4446 At the time that f is created, it can't capture the current value of $a,
4447 since the anonymous subroutine hasn't been created yet. Conversely,
4448 the following won't give a warning since the anonymous subroutine has by
4449 now been created and is live:
4451 sub { my $a; eval 'sub f { $a }' }->();
4453 The second situation is caused by an eval accessing a variable that has
4454 gone out of scope, for example,
4462 Here, when the '$a' in the eval is being compiled, f() is not currently being
4463 executed, so its $a is not available for capture.
4465 =item Variable "%s" is not imported%s
4467 (F) While "use strict" in effect, you referred to a global variable that
4468 you apparently thought was imported from another module, because
4469 something else of the same name (usually a subroutine) is exported by
4470 that module. It usually means you put the wrong funny character on the
4471 front of your variable.
4473 =item Variable length lookbehind not implemented in regex; marked by <-- HERE in m/%s/
4475 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
4476 known at compile time. The <-- HERE shows in the regular expression about
4477 where the problem was discovered. See L<perlre>.
4479 =item "%s" variable %s masks earlier declaration in same %s
4481 (W misc) A "my" or "our" variable has been redeclared in the current
4482 scope or statement, effectively eliminating all access to the previous
4483 instance. This is almost always a typographical error. Note that the
4484 earlier variable will still exist until the end of the scope or until
4485 all closure referents to it are destroyed.
4487 =item Variable syntax
4489 (A) You've accidentally run your script through B<csh> instead
4490 of Perl. Check the #! line, or manually feed your script into
4493 =item Variable "%s" will not stay shared
4495 (W closure) An inner (nested) I<named> subroutine is referencing a
4496 lexical variable defined in an outer named subroutine.
4498 When the inner subroutine is called, it will see the value of
4499 the outer subroutine's variable as it was before and during the *first*
4500 call to the outer subroutine; in this case, after the first call to the
4501 outer subroutine is complete, the inner and outer subroutines will no
4502 longer share a common value for the variable. In other words, the
4503 variable will no longer be shared.
4505 This problem can usually be solved by making the inner subroutine
4506 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
4507 reference variables in outer subroutines are created, they
4508 are automatically rebound to the current values of such variables.
4510 =item Version number must be a constant number
4512 (P) The attempt to translate a C<use Module n.n LIST> statement into
4513 its equivalent C<BEGIN> block found an internal inconsistency with
4516 =item v-string in use/require is non-portable
4518 (W portable) The use of v-strings is non-portable to older, pre-5.6, Perls.
4519 If you want your scripts to be backward portable, use the floating
4520 point version number: for example, instead of C<use 5.6.1> say
4521 C<use 5.006_001>. This of course won't help: the older Perls
4522 won't suddenly start understanding newer features, but at least
4523 they will show a sensible error message indicating the required
4526 =item Warning: something's wrong
4528 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
4529 you called it with no args and C<$_> was empty.
4531 =item Warning: unable to close filehandle %s properly
4533 (S) The implicit close() done by an open() got an error indication on
4534 the close(). This usually indicates your file system ran out of disk
4537 =item Warning: Use of "%s" without parentheses is ambiguous
4539 (S ambiguous) You wrote a unary operator followed by something that
4540 looks like a binary operator that could also have been interpreted as a
4541 term or unary operator. For instance, if you know that the rand
4542 function has a default argument of 1.0, and you write
4546 you may THINK you wrote the same thing as
4550 but in actual fact, you got
4554 So put in parentheses to say what you really mean.
4556 =item Wide character in %s
4558 (W utf8) Perl met a wide character (>255) when it wasn't expecting
4559 one. This warning is by default on for I/O (like print). The easiest
4560 way to quiet this warning is simply to add the C<:utf8> layer to the
4561 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
4562 warning is to add C<no warnings 'utf8';> but that is often closer to
4563 cheating. In general, you are supposed to explicitly mark the
4564 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
4566 =item Within []-length '%c' not allowed
4568 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
4569 C<TEMPLATE> always matches the same amount of packed bytes that can be
4570 determined from the template alone. This is not possible if it contains an
4571 of the codes @, /, U, u, w or a *-length. Redesign the template.
4573 =item write() on closed filehandle %s
4575 (W closed) The filehandle you're writing to got itself closed sometime
4576 before now. Check your control flow.
4578 =item %s "\x%s" does not map to Unicode
4580 When reading in different encodings Perl tries to map everything
4581 into Unicode characters. The bytes you read in are not legal in
4582 this encoding, for example
4584 utf8 "\xE4" does not map to Unicode
4586 if you try to read in the a-diaereses Latin-1 as UTF-8.
4588 =item 'X' outside of string
4590 (F) You had a (un)pack template that specified a relative position before
4591 the beginning of the string being (un)packed. See L<perlfunc/pack>.
4593 =item 'x' outside of string in unpack
4595 (F) You had a pack template that specified a relative position after
4596 the end of the string being unpacked. See L<perlfunc/pack>.
4598 =item Xsub "%s" called in sort
4600 (F) The use of an external subroutine as a sort comparison is not yet
4603 =item Xsub called in sort
4605 (F) The use of an external subroutine as a sort comparison is not yet
4608 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
4610 (F) And you probably never will, because you probably don't have the
4611 sources to your kernel, and your vendor probably doesn't give a rip
4612 about what you want. Your best bet is to put a setuid C wrapper around
4615 =item You need to quote "%s"
4617 (W syntax) You assigned a bareword as a signal handler name.
4618 Unfortunately, you already have a subroutine of that name declared,
4619 which means that Perl 5 will try to call the subroutine when the
4620 assignment is executed, which is probably not what you want. (If it IS
4621 what you want, put an & in front.)
4623 =item Your random numbers are not that random
4625 (F) When trying to initialise the random seed for hashes, Perl could
4626 not get any randomness out of your system. This usually indicates
4627 Something Very Wrong.