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 division by zero
1734 (F) You tried to divide a number by 0. Either something was wrong in
1735 your logic, or you need to put a conditional in to guard against
1738 =item Illegal hexadecimal digit %s ignored
1740 (W digit) You may have tried to use a character other than 0 - 9 or
1741 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
1742 number stopped before the illegal character.
1744 =item Illegal modulus zero
1746 (F) You tried to divide a number by 0 to get the remainder. Most
1747 numbers don't take to this kindly.
1749 =item Illegal number of bits in vec
1751 (F) The number of bits in vec() (the third argument) must be a power of
1752 two from 1 to 32 (or 64, if your platform supports that).
1754 =item Illegal octal digit %s
1756 (F) You used an 8 or 9 in an octal number.
1758 =item Illegal octal digit %s ignored
1760 (W digit) You may have tried to use an 8 or 9 in an octal number.
1761 Interpretation of the octal number stopped before the 8 or 9.
1763 =item Illegal switch in PERL5OPT: %s
1765 (X) The PERL5OPT environment variable may only be used to set the
1766 following switches: B<-[DIMUdmtw]>.
1768 =item Ill-formed CRTL environ value "%s"
1770 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
1771 internal environ array, and encountered an element without the C<=>
1772 delimiter used to separate keys from values. The element is ignored.
1774 =item Ill-formed message in prime_env_iter: |%s|
1776 (W internal) A warning peculiar to VMS. Perl tried to read a logical
1777 name or CLI symbol definition when preparing to iterate over %ENV, and
1778 didn't see the expected delimiter between key and value, so the line was
1781 =item Impossible to activate assertion call
1783 (W assertions) You're calling an assertion function in a block that is
1784 not under the control of the C<assertions> pragma.
1786 =item (in cleanup) %s
1788 (W misc) This prefix usually indicates that a DESTROY() method raised
1789 the indicated exception. Since destructors are usually called by the
1790 system at arbitrary points during execution, and often a vast number of
1791 times, the warning is issued only once for any number of failures that
1792 would otherwise result in the same message being repeated.
1794 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
1795 also result in this warning. See L<perlcall/G_KEEPERR>.
1797 =item In EBCDIC the v-string components cannot exceed 2147483647
1799 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
1800 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
1801 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
1803 =item Insecure dependency in %s
1805 (F) You tried to do something that the tainting mechanism didn't like.
1806 The tainting mechanism is turned on when you're running setuid or
1807 setgid, or when you specify B<-T> to turn it on explicitly. The
1808 tainting mechanism labels all data that's derived directly or indirectly
1809 from the user, who is considered to be unworthy of your trust. If any
1810 such data is used in a "dangerous" operation, you get this error. See
1811 L<perlsec> for more information.
1813 =item Insecure directory in %s
1815 (F) You can't use system(), exec(), or a piped open in a setuid or
1816 setgid script if C<$ENV{PATH}> contains a directory that is writable by
1817 the world. See L<perlsec>.
1819 =item Insecure $ENV{%s} while running %s
1821 (F) You can't use system(), exec(), or a piped open in a setuid or
1822 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
1823 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
1824 supplied (or potentially supplied) by the user. The script must set
1825 the path to a known value, using trustworthy data. See L<perlsec>.
1827 =item Integer overflow in %s number
1829 (W overflow) The hexadecimal, octal or binary number you have specified
1830 either as a literal or as an argument to hex() or oct() is too big for
1831 your architecture, and has been converted to a floating point number.
1832 On a 32-bit architecture the largest hexadecimal, octal or binary number
1833 representable without overflow is 0xFFFFFFFF, 037777777777, or
1834 0b11111111111111111111111111111111 respectively. Note that Perl
1835 transparently promotes all numbers to a floating point representation
1836 internally--subject to loss of precision errors in subsequent
1839 =item Integer overflow in version
1841 (F) Some portion of a version initialization is too large for the
1842 size of integers for your architecture. This is not a warning
1843 because there is no rational reason for a version to try and use a
1844 element larger than typically 2**32. This is usually caused by
1845 trying to use some odd mathematical operation as a version, like
1848 =item Internal disaster in regex; marked by <-- HERE in m/%s/
1850 (P) Something went badly wrong in the regular expression parser.
1851 The <-- HERE shows in the regular expression about where the problem was
1854 =item Internal inconsistency in tracking vforks
1856 (S) A warning peculiar to VMS. Perl keeps track of the number of times
1857 you've called C<fork> and C<exec>, to determine whether the current call
1858 to C<exec> should affect the current script or a subprocess (see
1859 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
1860 Perl is making a guess and treating this C<exec> as a request to
1861 terminate the Perl script and execute the specified command.
1863 =item Internal urp in regex; marked by <-- HERE in m/%s/
1865 (P) Something went badly awry in the regular expression parser. The
1866 <-- HERE shows in the regular expression about where the problem was
1869 =item %s (...) interpreted as function
1871 (W syntax) You've run afoul of the rule that says that any list operator
1872 followed by parentheses turns into a function, with all the list
1873 operators arguments found inside the parentheses. See
1874 L<perlop/Terms and List Operators (Leftward)>.
1876 =item Invalid %s attribute: %s
1878 The indicated attribute for a subroutine or variable was not recognized
1879 by Perl or by a user-supplied handler. See L<attributes>.
1881 =item Invalid %s attributes: %s
1883 The indicated attributes for a subroutine or variable were not
1884 recognized by Perl or by a user-supplied handler. See L<attributes>.
1886 =item Invalid conversion in %s: "%s"
1888 (W printf) Perl does not understand the given format conversion. See
1889 L<perlfunc/sprintf>.
1891 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
1893 (F) The range specified in a character class had a minimum character
1894 greater than the maximum character. One possibility is that you forgot the
1895 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
1896 up to C<ff>. The <-- HERE shows in the regular expression about where the
1897 problem was discovered. See L<perlre>.
1899 =item Invalid range "%s" in transliteration operator
1901 (F) The range specified in the tr/// or y/// operator had a minimum
1902 character greater than the maximum character. See L<perlop>.
1904 =item Invalid separator character %s in attribute list
1906 (F) Something other than a colon or whitespace was seen between the
1907 elements of an attribute list. If the previous attribute had a
1908 parenthesised parameter list, perhaps that list was terminated too soon.
1911 =item Invalid separator character %s in PerlIO layer specification %s
1913 (W layer) When pushing layers onto the Perl I/O system, something other than a
1914 colon or whitespace was seen between the elements of a layer list.
1915 If the previous attribute had a parenthesised parameter list, perhaps that
1916 list was terminated too soon.
1918 =item Invalid type '%s' in %s
1920 (F) The given character is not a valid pack or unpack type.
1921 See L<perlfunc/pack>.
1922 (W) The given character is not a valid pack or unpack type but used to be
1925 =item Invalid version format (multiple underscores)
1927 (F) Versions may contain at most a single underscore, which signals
1928 that the version is a beta release. See L<version> for the allowed
1931 =item Invalid version format (underscores before decimal)
1933 (F) Versions may not contain decimals after the optional underscore.
1934 See L<version> for the allowed version formats.
1936 =item ioctl is not implemented
1938 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1939 strange for a machine that supports C.
1941 =item ioctl() on unopened %s
1943 (W unopened) You tried ioctl() on a filehandle that was never opened.
1944 Check you control flow and number of arguments.
1946 =item IO layers (like "%s") unavailable
1948 (F) Your Perl has not been configured to have PerlIO, and therefore
1949 you cannot use IO layers. To have PerlIO Perl must be configured
1952 =item IO::Socket::atmark not implemented on this architecture
1954 (F) Your machine doesn't implement the sockatmark() functionality,
1955 neither as a system call or an ioctl call (SIOCATMARK).
1957 =item $* is no longer supported
1959 (D deprecated) The special variable C<$*>, deprecated in older perls, has
1960 been removed as of 5.9.0 and is no longer supported. You should use the
1961 C<//m> and C<//s> regexp modifiers instead.
1963 =item `%s' is not a code reference
1965 (W overload) The second (fourth, sixth, ...) argument of overload::constant
1966 needs to be a code reference. Either an anonymous subroutine, or a reference
1969 =item `%s' is not an overloadable type
1971 (W overload) You tried to overload a constant type the overload package is
1974 =item junk on end of regexp
1976 (P) The regular expression parser is confused.
1978 =item Label not found for "last %s"
1980 (F) You named a loop to break out of, but you're not currently in a loop
1981 of that name, not even if you count where you were called from. See
1984 =item Label not found for "next %s"
1986 (F) You named a loop to continue, but you're not currently in a loop of
1987 that name, not even if you count where you were called from. See
1990 =item Label not found for "redo %s"
1992 (F) You named a loop to restart, but you're not currently in a loop of
1993 that name, not even if you count where you were called from. See
1996 =item leaving effective %s failed
1998 (F) While under the C<use filetest> pragma, switching the real and
1999 effective uids or gids failed.
2001 =item length/code after end of string in unpack
2003 (F) While unpacking, the string buffer was alread used up when an unpack
2004 length/code combination tried to obtain more data. This results in
2005 an undefined value for the length. See L<perlfunc/pack>.
2007 =item listen() on closed socket %s
2009 (W closed) You tried to do a listen on a closed socket. Did you forget
2010 to check the return value of your socket() call? See
2013 =item Lookbehind longer than %d not implemented in regex; marked by <-- HERE in m/%s/
2015 (F) There is currently a limit on the length of string which lookbehind can
2016 handle. This restriction may be eased in a future release. The <-- HERE
2017 shows in the regular expression about where the problem was discovered.
2019 =item lstat() on filehandle %s
2021 (W io) You tried to do an lstat on a filehandle. What did you mean
2022 by that? lstat() makes sense only on filenames. (Perl did a fstat()
2023 instead on the filehandle.)
2025 =item Lvalue subs returning %s not implemented yet
2027 (F) Due to limitations in the current implementation, array and hash
2028 values cannot be returned in subroutines used in lvalue context. See
2029 L<perlsub/"Lvalue subroutines">.
2031 =item Malformed integer in [] in pack
2033 (F) Between the brackets enclosing a numeric repeat count only digits
2034 are permitted. See L<perlfunc/pack>.
2036 =item Malformed integer in [] in unpack
2038 (F) Between the brackets enclosing a numeric repeat count only digits
2039 are permitted. See L<perlfunc/pack>.
2041 =item Malformed PERLLIB_PREFIX
2043 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2050 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2051 a builtin library search path, prefix2 is substituted. The error may
2052 appear if components are not found, or are too long. See
2053 "PERLLIB_PREFIX" in L<perlos2>.
2055 =item Malformed prototype for %s: %s
2057 (F) You tried to use a function with a malformed prototype. The
2058 syntax of function prototypes is given a brief compile-time check for
2059 obvious errors like invalid characters. A more rigorous check is run
2060 when the function is called.
2062 =item Malformed UTF-8 character (%s)
2064 Perl detected something that didn't comply with UTF-8 encoding rules.
2066 One possible cause is that you read in data that you thought to be in
2067 UTF-8 but it wasn't (it was for example legacy 8-bit data). Another
2068 possibility is careless use of utf8::upgrade().
2070 =item Malformed UTF-16 surrogate
2072 Perl thought it was reading UTF-16 encoded character data but while
2073 doing it Perl met a malformed Unicode surrogate.
2075 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2077 (W regexp) The pattern you've specified would be an infinite loop if the
2078 regular expression engine didn't specifically check for that. The <-- HERE
2079 shows in the regular expression about where the problem was discovered.
2082 =item "%s" may clash with future reserved word
2084 (W) This warning may be due to running a perl5 script through a perl4
2085 interpreter, especially if the word that is being warned about is
2088 =item % may not be used in pack
2090 (F) You can't pack a string by supplying a checksum, because the
2091 checksumming process loses information, and you can't go the other way.
2092 See L<perlfunc/unpack>.
2094 =item Method for operation %s not found in package %s during blessing
2096 (F) An attempt was made to specify an entry in an overloading table that
2097 doesn't resolve to a valid subroutine. See L<overload>.
2099 =item Method %s not permitted
2103 =item Might be a runaway multi-line %s string starting on line %d
2105 (S) An advisory indicating that the previous error may have been caused
2106 by a missing delimiter on a string or pattern, because it eventually
2107 ended earlier on the current line.
2109 =item Misplaced _ in number
2111 (W syntax) An underscore (underbar) in a numeric constant did not
2112 separate two digits.
2114 =item Missing %sbrace%s on \N{}
2116 (F) Wrong syntax of character name literal C<\N{charname}> within
2117 double-quotish context.
2119 =item Missing comma after first argument to %s function
2121 (F) While certain functions allow you to specify a filehandle or an
2122 "indirect object" before the argument list, this ain't one of them.
2124 =item Missing command in piped open
2126 (W pipe) You used the C<open(FH, "| command")> or
2127 C<open(FH, "command |")> construction, but the command was missing or
2130 =item Missing control char name in \c
2132 (F) A double-quoted string ended with "\c", without the required control
2135 =item Missing name in "my sub"
2137 (F) The reserved syntax for lexically scoped subroutines requires that
2138 they have a name with which they can be found.
2140 =item Missing $ on loop variable
2142 (F) Apparently you've been programming in B<csh> too much. Variables
2143 are always mentioned with the $ in Perl, unlike in the shells, where it
2144 can vary from one line to the next.
2146 =item (Missing operator before %s?)
2148 (S syntax) This is an educated guess made in conjunction with the message
2149 "%s found where operator expected". Often the missing operator is a comma.
2151 =item Missing right brace on %s
2153 (F) Missing right brace in C<\p{...}> or C<\P{...}>.
2155 =item Missing right curly or square bracket
2157 (F) The lexer counted more opening curly or square brackets than closing
2158 ones. As a general rule, you'll find it's missing near the place you
2161 =item (Missing semicolon on previous line?)
2163 (S syntax) This is an educated guess made in conjunction with the message
2164 "%s found where operator expected". Don't automatically put a semicolon on
2165 the previous line just because you saw this message.
2167 =item Modification of a read-only value attempted
2169 (F) You tried, directly or indirectly, to change the value of a
2170 constant. You didn't, of course, try "2 = 1", because the compiler
2171 catches that. But an easy way to do the same thing is:
2173 sub mod { $_[0] = 1 }
2176 Another way is to assign to a substr() that's off the end of the string.
2178 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2179 is aliased to a constant in the look I<LIST>:
2182 foreach my $n ($x, 2) {
2183 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2186 =item Modification of non-creatable array value attempted, %s
2188 (F) You tried to make an array value spring into existence, and the
2189 subscript was probably negative, even counting from end of the array
2192 =item Modification of non-creatable hash value attempted, %s
2194 (P) You tried to make a hash value spring into existence, and it
2195 couldn't be created for some peculiar reason.
2197 =item Module name must be constant
2199 (F) Only a bare module name is allowed as the first argument to a "use".
2201 =item Module name required with -%c option
2203 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2204 you omitted the name of the module. Consult L<perlrun> for full details
2205 about C<-M> and C<-m>.
2207 =item More than one argument to open
2209 (F) The C<open> function has been asked to open multiple files. This
2210 can happen if you are trying to open a pipe to a command that takes a
2211 list of arguments, but have forgotten to specify a piped open mode.
2212 See L<perlfunc/open> for details.
2214 =item msg%s not implemented
2216 (F) You don't have System V message IPC on your system.
2218 =item Multidimensional syntax %s not supported
2220 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2221 They're written like C<$foo[1][2][3]>, as in C.
2223 =item '/' must be followed by 'a*', 'A*' or 'Z*'
2225 (F) You had a pack template indicating a counted-length string,
2226 Currently the only things that can have their length counted are a*, A*
2227 or Z*. See L<perlfunc/pack>.
2229 =item '/' must follow a numeric type in unpack
2231 (F) You had an unpack template that contained a '/', but this did not
2232 follow some unpack specification producing a numeric value.
2233 See L<perlfunc/pack>.
2235 =item "my sub" not yet implemented
2237 (F) Lexically scoped subroutines are not yet implemented. Don't try
2240 =item "my" variable %s can't be in a package
2242 (F) Lexically scoped variables aren't in a package, so it doesn't make
2243 sense to try to declare one with a package qualifier on the front. Use
2244 local() if you want to localize a package variable.
2246 =item Name "%s::%s" used only once: possible typo
2248 (W once) Typographical errors often show up as unique variable names.
2249 If you had a good reason for having a unique name, then just mention it
2250 again somehow to suppress the message. The C<our> declaration is
2251 provided for this purpose.
2253 NOTE: This warning detects symbols that have been used only once so $c, @c,
2254 %c, *c, &c, sub c{}, c(), and c (the filehandle or format) are considered
2255 the same; if a program uses $c only once but also uses any of the others it
2256 will not trigger this warning.
2258 =item Negative '/' count in unpack
2260 (F) The length count obtained from a length/code unpack operation was
2261 negative. See L<perlfunc/pack>.
2263 =item Negative length
2265 (F) You tried to do a read/write/send/recv operation with a buffer
2266 length that is less than 0. This is difficult to imagine.
2268 =item Negative offset to vec in lvalue context
2270 (F) When C<vec> is called in an lvalue context, the second argument must be
2271 greater than or equal to zero.
2273 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2275 (F) You can't quantify a quantifier without intervening parentheses. So
2276 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2277 expression about where the problem was discovered.
2279 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2280 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2282 =item %s never introduced
2284 (S internal) The symbol in question was declared but somehow went out of
2285 scope before it could possibly have been used.
2287 =item Newline in left-justified string for %s
2289 (W printf) There is a newline in a string to be left justified by
2290 C<printf> or C<sprintf>.
2292 The padding spaces will appear after the newline, which is probably not
2293 what you wanted. Usually you should remove the newline from the string
2294 and put formatting characters in the C<sprintf> format.
2296 =item No %s allowed while running setuid
2298 (F) Certain operations are deemed to be too insecure for a setuid or
2299 setgid script to even be allowed to attempt. Generally speaking there
2300 will be another way to do what you want that is, if not secure, at least
2301 securable. See L<perlsec>.
2303 =item No comma allowed after %s
2305 (F) A list operator that has a filehandle or "indirect object" is not
2306 allowed to have a comma between that and the following arguments.
2307 Otherwise it'd be just another one of the arguments.
2309 One possible cause for this is that you expected to have imported a
2310 constant to your name space with B<use> or B<import> while no such
2311 importing took place, it may for example be that your operating system
2312 does not support that particular constant. Hopefully you did use an
2313 explicit import list for the constants you expect to see, please see
2314 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2315 would probably have caught this error earlier it naturally does not
2316 remedy the fact that your operating system still does not support that
2317 constant. Maybe you have a typo in the constants of the symbol import
2318 list of B<use> or B<import> or in the constant name at the line where
2319 this error was triggered?
2321 =item No command into which to pipe on command line
2323 (F) An error peculiar to VMS. Perl handles its own command line
2324 redirection, and found a '|' at the end of the command line, so it
2325 doesn't know where you want to pipe the output from this command.
2327 =item No DB::DB routine defined
2329 (F) The currently executing code was compiled with the B<-d> switch, but
2330 for some reason the perl5db.pl file (or some facsimile thereof) didn't
2331 define a routine to be called at the beginning of each statement. Which
2332 is odd, because the file should have been required automatically, and
2333 should have blown up the require if it didn't parse right.
2335 =item No dbm on this machine
2337 (P) This is counted as an internal error, because every machine should
2338 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2340 =item No DBsub routine
2342 (F) The currently executing code was compiled with the B<-d> switch,
2343 but for some reason the perl5db.pl file (or some facsimile thereof)
2344 didn't define a DB::sub routine to be called at the beginning of each
2345 ordinary subroutine call.
2347 =item No B<-e> allowed in setuid scripts
2349 (F) A setuid script can't be specified by the user.
2351 =item No error file after 2> or 2>> on command line
2353 (F) An error peculiar to VMS. Perl handles its own command line
2354 redirection, and found a '2>' or a '2>>' on the command line, but can't
2355 find the name of the file to which to write data destined for stderr.
2357 =item No group ending character '%c' found in template
2359 (F) A pack or unpack template has an opening '(' or '[' without its
2360 matching counterpart. See L<perlfunc/pack>.
2362 =item No input file after < on command line
2364 (F) An error peculiar to VMS. Perl handles its own command line
2365 redirection, and found a '<' on the command line, but can't find the
2366 name of the file from which to read data for stdin.
2370 (F) The setuid emulator requires that scripts have a well-formed #! line
2371 even on machines that don't support the #! construct.
2373 =item "no" not allowed in expression
2375 (F) The "no" keyword is recognized and executed at compile time, and
2376 returns no useful value. See L<perlmod>.
2378 =item No output file after > on command line
2380 (F) An error peculiar to VMS. Perl handles its own command line
2381 redirection, and found a lone '>' at the end of the command line, so it
2382 doesn't know where you wanted to redirect stdout.
2384 =item No output file after > or >> on command line
2386 (F) An error peculiar to VMS. Perl handles its own command line
2387 redirection, and found a '>' or a '>>' on the command line, but can't
2388 find the name of the file to which to write data destined for stdout.
2390 =item No package name allowed for variable %s in "our"
2392 (F) Fully qualified variable names are not allowed in "our"
2393 declarations, because that doesn't make much sense under existing
2394 semantics. Such syntax is reserved for future extensions.
2396 =item No Perl script found in input
2398 (F) You called C<perl -x>, but no line was found in the file beginning
2399 with #! and containing the word "perl".
2401 =item No setregid available
2403 (F) Configure didn't find anything resembling the setregid() call for
2406 =item No setreuid available
2408 (F) Configure didn't find anything resembling the setreuid() call for
2411 =item No space allowed after -%c
2413 (F) The argument to the indicated command line switch must follow
2414 immediately after the switch, without intervening spaces.
2416 =item No %s specified for -%c
2418 (F) The indicated command line switch needs a mandatory argument, but
2419 you haven't specified one.
2421 =item No such class %s
2423 (F) You provided a class qualifier in a "my" or "our" declaration, but
2424 this class doesn't exist at this point in your program.
2426 =item No such pipe open
2428 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
2429 close a pipe which hadn't been opened. This should have been caught
2430 earlier as an attempt to close an unopened filehandle.
2432 =item No such signal: SIG%s
2434 (W signal) You specified a signal name as a subscript to %SIG that was
2435 not recognized. Say C<kill -l> in your shell to see the valid signal
2436 names on your system.
2438 =item Not a CODE reference
2440 (F) Perl was trying to evaluate a reference to a code value (that is, a
2441 subroutine), but found a reference to something else instead. You can
2442 use the ref() function to find out what kind of ref it really was. See
2445 =item Not a format reference
2447 (F) I'm not sure how you managed to generate a reference to an anonymous
2448 format, but this indicates you did, and that it didn't exist.
2450 =item Not a GLOB reference
2452 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
2453 symbol table entry that looks like C<*foo>), but found a reference to
2454 something else instead. You can use the ref() function to find out what
2455 kind of ref it really was. See L<perlref>.
2457 =item Not a HASH reference
2459 (F) Perl was trying to evaluate a reference to a hash value, but found a
2460 reference to something else instead. You can use the ref() function to
2461 find out what kind of ref it really was. See L<perlref>.
2463 =item Not an ARRAY reference
2465 (F) Perl was trying to evaluate a reference to an array value, but found
2466 a reference to something else instead. You can use the ref() function
2467 to find out what kind of ref it really was. See L<perlref>.
2469 =item Not a perl script
2471 (F) The setuid emulator requires that scripts have a well-formed #! line
2472 even on machines that don't support the #! construct. The line must
2475 =item Not a SCALAR reference
2477 (F) Perl was trying to evaluate a reference to a scalar value, but found
2478 a reference to something else instead. You can use the ref() function
2479 to find out what kind of ref it really was. See L<perlref>.
2481 =item Not a subroutine reference
2483 (F) Perl was trying to evaluate a reference to a code value (that is, a
2484 subroutine), but found a reference to something else instead. You can
2485 use the ref() function to find out what kind of ref it really was. See
2488 =item Not a subroutine reference in overload table
2490 (F) An attempt was made to specify an entry in an overloading table that
2491 doesn't somehow point to a valid subroutine. See L<overload>.
2493 =item Not enough arguments for %s
2495 (F) The function requires more arguments than you specified.
2497 =item Not enough format arguments
2499 (W syntax) A format specified more picture fields than the next line
2500 supplied. See L<perlform>.
2504 (A) You've accidentally run your script through the Bourne shell instead
2505 of Perl. Check the #! line, or manually feed your script into Perl
2508 =item no UTC offset information; assuming local time is UTC
2510 (S) A warning peculiar to VMS. Perl was unable to find the local
2511 timezone offset, so it's assuming that local system time is equivalent
2512 to UTC. If it's not, define the logical name
2513 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
2514 need to be added to UTC to get local time.
2516 =item Null filename used
2518 (F) You can't require the null filename, especially because on many
2519 machines that means the current directory! See L<perlfunc/require>.
2521 =item NULL OP IN RUN
2523 (P debugging) Some internal routine called run() with a null opcode
2526 =item Null picture in formline
2528 (F) The first argument to formline must be a valid format picture
2529 specification. It was found to be empty, which probably means you
2530 supplied it an uninitialized value. See L<perlform>.
2534 (P) An attempt was made to realloc NULL.
2536 =item NULL regexp argument
2538 (P) The internal pattern matching routines blew it big time.
2540 =item NULL regexp parameter
2542 (P) The internal pattern matching routines are out of their gourd.
2544 =item Number too long
2546 (F) Perl limits the representation of decimal numbers in programs to
2547 about 250 characters. You've exceeded that length. Future
2548 versions of Perl are likely to eliminate this arbitrary limitation. In
2549 the meantime, try using scientific notation (e.g. "1e6" instead of
2552 =item Octal number in vector unsupported
2554 (F) Numbers with a leading C<0> are not currently allowed in vectors.
2555 The octal number interpretation of such numbers may be supported in a
2558 =item Octal number > 037777777777 non-portable
2560 (W portable) The octal number you specified is larger than 2**32-1
2561 (4294967295) and therefore non-portable between systems. See
2562 L<perlport> for more on portability concerns.
2564 See also L<perlport> for writing portable code.
2566 =item Odd number of arguments for overload::constant
2568 (W overload) The call to overload::constant contained an odd number of
2569 arguments. The arguments should come in pairs.
2571 =item Odd number of elements in anonymous hash
2573 (W misc) You specified an odd number of elements to initialize a hash,
2574 which is odd, because hashes come in key/value pairs.
2576 =item Odd number of elements in hash assignment
2578 (W misc) You specified an odd number of elements to initialize a hash,
2579 which is odd, because hashes come in key/value pairs.
2581 =item Offset outside string
2583 (F) You tried to do a read/write/send/recv operation with an offset
2584 pointing outside the buffer. This is difficult to imagine. The sole
2585 exception to this is that C<sysread()>ing past the buffer will extend
2586 the buffer and zero pad the new area.
2588 =item %s() on unopened %s
2590 (W unopened) An I/O operation was attempted on a filehandle that was
2591 never initialized. You need to do an open(), a sysopen(), or a socket()
2592 call, or call a constructor from the FileHandle package.
2594 =item -%s on unopened filehandle %s
2596 (W unopened) You tried to invoke a file test operator on a filehandle
2597 that isn't open. Check your control flow. See also L<perlfunc/-X>.
2601 (S internal) An internal warning that the grammar is screwed up.
2605 (S internal) An internal warning that the grammar is screwed up.
2607 =item Operation `%s': no method found, %s
2609 (F) An attempt was made to perform an overloaded operation for which no
2610 handler was defined. While some handlers can be autogenerated in terms
2611 of other handlers, there is no default handler for any operation, unless
2612 C<fallback> overloading key is specified to be true. See L<overload>.
2614 =item Operator or semicolon missing before %s
2616 (S ambiguous) You used a variable or subroutine call where the parser
2617 was expecting an operator. The parser has assumed you really meant to
2618 use an operator, but this is highly likely to be incorrect. For
2619 example, if you say "*foo *foo" it will be interpreted as if you said
2622 =item "our" variable %s redeclared
2624 (W misc) You seem to have already declared the same global once before
2625 in the current lexical scope.
2627 =item Out of memory!
2629 (X) The malloc() function returned 0, indicating there was insufficient
2630 remaining memory (or virtual memory) to satisfy the request. Perl has
2631 no option but to exit immediately.
2633 At least in Unix you may be able to get past this by increasing your
2634 process datasize limits: in csh/tcsh use C<limit> and
2635 C<limit datasize n> (where C<n> is the number of kilobytes) to check
2636 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
2637 and C<ulimit -d n>, respectively.
2639 =item Out of memory during "large" request for %s
2641 (F) The malloc() function returned 0, indicating there was insufficient
2642 remaining memory (or virtual memory) to satisfy the request. However,
2643 the request was judged large enough (compile-time default is 64K), so a
2644 possibility to shut down by trapping this error is granted.
2646 =item Out of memory during request for %s
2648 (X|F) The malloc() function returned 0, indicating there was
2649 insufficient remaining memory (or virtual memory) to satisfy the
2652 The request was judged to be small, so the possibility to trap it
2653 depends on the way perl was compiled. By default it is not trappable.
2654 However, if compiled for this, Perl may use the contents of C<$^M> as an
2655 emergency pool after die()ing with this message. In this case the error
2656 is trappable I<once>, and the error message will include the line and file
2657 where the failed request happened.
2659 =item Out of memory during ridiculously large request
2661 (F) You can't allocate more than 2^31+"small amount" bytes. This error
2662 is most likely to be caused by a typo in the Perl program. e.g.,
2663 C<$arr[time]> instead of C<$arr[$time]>.
2665 =item Out of memory for yacc stack
2667 (F) The yacc parser wanted to grow its stack so it could continue
2668 parsing, but realloc() wouldn't give it more memory, virtual or
2671 =item '@' outside of string in unpack
2673 (F) You had a template that specified an absolute position outside
2674 the string being unpacked. See L<perlfunc/pack>.
2676 =item %s package attribute may clash with future reserved word: %s
2678 (W reserved) A lowercase attribute name was used that had a
2679 package-specific handler. That name might have a meaning to Perl itself
2680 some day, even though it doesn't yet. Perhaps you should use a
2681 mixed-case attribute name, instead. See L<attributes>.
2683 =item pack/unpack repeat count overflow
2685 (F) You can't specify a repeat count so large that it overflows your
2686 signed integers. See L<perlfunc/pack>.
2690 (W io) A single call to write() produced more lines than can fit on a
2691 page. See L<perlform>.
2695 (P) An internal error.
2697 =item panic: array extend
2699 (P) An attempt was made to extend an array beyond the largest possible
2702 =item panic: ck_grep
2704 (P) Failed an internal consistency check trying to compile a grep.
2706 =item panic: ck_split
2708 (P) Failed an internal consistency check trying to compile a split.
2710 =item panic: corrupt saved stack index
2712 (P) The savestack was requested to restore more localized values than
2713 there are in the savestack.
2715 =item panic: del_backref
2717 (P) Failed an internal consistency check while trying to reset a weak
2720 =item panic: Devel::DProf inconsistent subroutine return
2722 (P) Devel::DProf called a subroutine that exited using goto(LABEL),
2723 last(LABEL) or next(LABEL). Leaving that way a subroutine called from
2724 an XSUB will lead very probably to a crash of the interpreter. This is
2725 a bug that will hopefully one day get fixed.
2729 (P) We popped the context stack to an eval context, and then discovered
2730 it wasn't an eval context.
2732 =item panic: do_subst
2734 (P) The internal pp_subst() routine was called with invalid operational
2737 =item panic: do_trans_%s
2739 (P) The internal do_trans routines were called with invalid operational
2744 (P) The library function frexp() failed, making printf("%f") impossible.
2748 (P) We popped the context stack to a context with the specified label,
2749 and then discovered it wasn't a context we know how to do a goto in.
2751 =item panic: INTERPCASEMOD
2753 (P) The lexer got into a bad state at a case modifier.
2755 =item panic: INTERPCONCAT
2757 (P) The lexer got into a bad state parsing a string with brackets.
2759 =item panic: kid popen errno read
2761 (F) forked child returned an incomprehensible message about its errno.
2765 (P) We popped the context stack to a block context, and then discovered
2766 it wasn't a block context.
2768 =item panic: leave_scope clearsv
2770 (P) A writable lexical variable became read-only somehow within the
2773 =item panic: leave_scope inconsistency
2775 (P) The savestack probably got out of sync. At least, there was an
2776 invalid enum on the top of it.
2778 =item panic: list extend
2780 (P) An attempt was made to extend a list beyond the largest possible
2783 =item panic: magic_killbackrefs
2785 (P) Failed an internal consistency check while trying to reset all weak
2786 references to an object.
2790 (P) Something requested a negative number of bytes of malloc.
2792 =item panic: mapstart
2794 (P) The compiler is screwed up with respect to the map() function.
2796 =item panic: memory wrap
2798 (P) Something tried to allocate more memory than possible.
2800 =item panic: null array
2802 (P) One of the internal array routines was passed a null AV pointer.
2804 =item panic: pad_alloc
2806 (P) The compiler got confused about which scratch pad it was allocating
2807 and freeing temporaries and lexicals from.
2809 =item panic: pad_free curpad
2811 (P) The compiler got confused about which scratch pad it was allocating
2812 and freeing temporaries and lexicals from.
2814 =item panic: pad_free po
2816 (P) An invalid scratch pad offset was detected internally.
2818 =item panic: pad_reset curpad
2820 (P) The compiler got confused about which scratch pad it was allocating
2821 and freeing temporaries and lexicals from.
2823 =item panic: pad_sv po
2825 (P) An invalid scratch pad offset was detected internally.
2827 =item panic: pad_swipe curpad
2829 (P) The compiler got confused about which scratch pad it was allocating
2830 and freeing temporaries and lexicals from.
2832 =item panic: pad_swipe po
2834 (P) An invalid scratch pad offset was detected internally.
2836 =item panic: pp_iter
2838 (P) The foreach iterator got called in a non-loop context frame.
2840 =item panic: pp_match%s
2842 (P) The internal pp_match() routine was called with invalid operational
2845 =item panic: pp_split
2847 (P) Something terrible went wrong in setting up for the split.
2849 =item panic: realloc
2851 (P) Something requested a negative number of bytes of realloc.
2853 =item panic: restartop
2855 (P) Some internal routine requested a goto (or something like it), and
2856 didn't supply the destination.
2860 (P) We popped the context stack to a subroutine or eval context, and
2861 then discovered it wasn't a subroutine or eval context.
2863 =item panic: scan_num
2865 (P) scan_num() got called on something that wasn't a number.
2867 =item panic: string extend
2869 (P) An attempt was made to extend a string beyond the largest possible
2872 =item panic: sv_insert
2874 (P) The sv_insert() routine was told to remove more string than there
2877 =item panic: top_env
2879 (P) The compiler attempted to do a goto, or something weird like that.
2881 =item panic: utf16_to_utf8: odd bytelen
2883 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
2884 to even) byte length.
2888 (P) The lexer got into a bad state while processing a case modifier.
2890 =item Parentheses missing around "%s" list
2892 (W parenthesis) You said something like
2898 my ($foo, $bar) = @_;
2900 Remember that "my", "our", and "local" bind tighter than comma.
2902 =item C<-p> destination: %s
2904 (F) An error occurred during the implicit output invoked by the C<-p>
2905 command-line switch. (This output goes to STDOUT unless you've
2906 redirected it with select().)
2908 =item (perhaps you forgot to load "%s"?)
2910 (F) This is an educated guess made in conjunction with the message
2911 "Can't locate object method \"%s\" via package \"%s\"". It often means
2912 that a method requires a package that has not been loaded.
2914 =item Perl %s required--this is only version %s, stopped
2916 (F) The module in question uses features of a version of Perl more
2917 recent than the currently running version. How long has it been since
2918 you upgraded, anyway? See L<perlfunc/require>.
2920 =item Perl_my_%s() not available
2922 (F) Your platform has very uncommon byte-order and integer size,
2923 so it was not possible to set up some or all fixed-width byte-order
2924 conversion functions. This is only a problem when you're using the
2925 '<' or '>' modifiers in (un)pack templates. See L<perlfunc/pack>.
2927 =item PERL_SH_DIR too long
2929 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2930 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
2932 =item PERL_SIGNALS illegal: "%s"
2934 See L<perlrun/PERL_SIGNALS> for legal values.
2936 =item perl: warning: Setting locale failed.
2938 (S) The whole warning message will look something like:
2940 perl: warning: Setting locale failed.
2941 perl: warning: Please check that your locale settings:
2944 are supported and installed on your system.
2945 perl: warning: Falling back to the standard locale ("C").
2947 Exactly what were the failed locale settings varies. In the above the
2948 settings were that the LC_ALL was "En_US" and the LANG had no value.
2949 This error means that Perl detected that you and/or your operating
2950 system supplier and/or system administrator have set up the so-called
2951 locale system but Perl could not use those settings. This was not
2952 dead serious, fortunately: there is a "default locale" called "C" that
2953 Perl can and will use, the script will be run. Before you really fix
2954 the problem, however, you will get the same error message each time
2955 you run Perl. How to really fix the problem can be found in
2956 L<perllocale> section B<LOCALE PROBLEMS>.
2958 =item Permission denied
2960 (F) The setuid emulator in suidperl decided you were up to no good.
2962 =item pid %x not a child
2964 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
2965 process which isn't a subprocess of the current process. While this is
2966 fine from VMS' perspective, it's probably not what you intended.
2968 =item 'P' must have an explicit size in unpack
2970 (F) The unpack format P must have an explicit size, not "*".
2972 =item B<-P> not allowed for setuid/setgid script
2974 (F) The script would have to be opened by the C preprocessor by name,
2975 which provides a race condition that breaks security.
2977 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
2979 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
2980 shows in the regular expression about where the problem was discovered.
2981 Note that the POSIX character classes do B<not> have the C<is> prefix
2982 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
2983 not C<isprint>. See L<perlre>.
2985 =item POSIX getpgrp can't take an argument
2987 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
2988 the BSD version, which takes a pid.
2990 =item POSIX syntax [%s] belongs inside character classes in regex; marked by <-- HERE in m/%s/
2992 (W regexp) The character class constructs [: :], [= =], and [. .] go
2993 I<inside> character classes, the [] are part of the construct, for example:
2994 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
2995 implemented; they are simply placeholders for future extensions and will
2996 cause fatal errors. The <-- HERE shows in the regular expression about
2997 where the problem was discovered. See L<perlre>.
2999 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3001 (F regexp) Within regular expression character classes ([]) the syntax
3002 beginning with "[." and ending with ".]" is reserved for future extensions.
3003 If you need to represent those character sequences inside a regular
3004 expression character class, just quote the square brackets with the
3005 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
3006 about where the problem was discovered. See L<perlre>.
3008 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
3010 (F) Within regular expression character classes ([]) the syntax beginning
3011 with "[=" and ending with "=]" is reserved for future extensions. If you
3012 need to represent those character sequences inside a regular expression
3013 character class, just quote the square brackets with the backslash: "\[="
3014 and "=\]". The <-- HERE shows in the regular expression about where the
3015 problem was discovered. See L<perlre>.
3017 =item Possible attempt to put comments in qw() list
3019 (W qw) qw() lists contain items separated by whitespace; as with literal
3020 strings, comment characters are not ignored, but are instead treated as
3021 literal data. (You may have used different delimiters than the
3022 parentheses shown here; braces are also frequently used.)
3024 You probably wrote something like this:
3031 when you should have written this:
3038 If you really want comments, build your list the
3039 old-fashioned way, with quotes and commas:
3043 'b', # another comment
3046 =item Possible attempt to separate words with commas
3048 (W qw) qw() lists contain items separated by whitespace; therefore
3049 commas aren't needed to separate the items. (You may have used
3050 different delimiters than the parentheses shown here; braces are also
3053 You probably wrote something like this:
3057 which puts literal commas into some of the list items. Write it without
3058 commas if you don't want them to appear in your data:
3062 =item Possible memory corruption: %s overflowed 3rd argument
3064 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
3065 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
3066 end of the buffer just in case. This sentinel byte got clobbered, and
3067 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
3069 =item Possible precedence problem on bitwise %c operator
3071 (W precedence) Your program uses a bitwise logical operator in conjunction
3072 with a numeric comparison operator, like this :
3074 if ($x & $y == 0) { ... }
3076 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
3077 higher precedence of C<==>. This is probably not what you want. (If you
3078 really meant to write this, disable the warning, or, better, put the
3079 parentheses explicitly and write C<$x & ($y == 0)>).
3081 =item Possible unintended interpolation of %s in string
3083 (W ambiguous) You said something like `@foo' in a double-quoted string
3084 but there was no array C<@foo> in scope at the time. If you wanted a
3085 literal @foo, then write it as \@foo; otherwise find out what happened
3086 to the array you apparently lost track of.
3088 =item Possible Y2K bug: %s
3090 (W y2k) You are concatenating the number 19 with another number, which
3091 could be a potential Year 2000 problem.
3093 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
3095 (D deprecated) You have written something like this:
3099 use attrs qw(locked);
3102 You should use the new declaration syntax instead.
3108 The C<use attrs> pragma is now obsolete, and is only provided for
3109 backward-compatibility. See L<perlsub/"Subroutine Attributes">.
3111 =item Precedence problem: open %s should be open(%s)
3113 (S precedence) The old irregular construct
3117 is now misinterpreted as
3121 because of the strict regularization of Perl 5's grammar into unary and
3122 list operators. (The old open was a little of both.) You must put
3123 parentheses around the filehandle, or use the new "or" operator instead
3126 =item Premature end of script headers
3130 =item printf() on closed filehandle %s
3132 (W closed) The filehandle you're writing to got itself closed sometime
3133 before now. Check your control flow.
3135 =item print() on closed filehandle %s
3137 (W closed) The filehandle you're printing on got itself closed sometime
3138 before now. Check your control flow.
3140 =item Process terminated by SIG%s
3142 (W) This is a standard message issued by OS/2 applications, while *nix
3143 applications die in silence. It is considered a feature of the OS/2
3144 port. One can easily disable this by appropriate sighandlers, see
3145 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
3148 =item Prototype mismatch: %s vs %s
3150 (S prototype) The subroutine being declared or defined had previously been
3151 declared or defined with a different function prototype.
3153 =item Prototype not terminated
3155 (F) You've omitted the closing parenthesis in a function prototype
3158 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
3160 (F) You started a regular expression with a quantifier. Backslash it if you
3161 meant it literally. The <-- HERE shows in the regular expression about
3162 where the problem was discovered. See L<perlre>.
3164 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
3166 (F) There is currently a limit to the size of the min and max values of the
3167 {min,max} construct. The <-- HERE shows in the regular expression about where
3168 the problem was discovered. See L<perlre>.
3170 =item Quantifier unexpected on zero-length expression; marked by <-- HERE in m/%s/
3172 (W regexp) You applied a regular expression quantifier in a place where
3173 it makes no sense, such as on a zero-width assertion. Try putting the
3174 quantifier inside the assertion instead. For example, the way to match
3175 "abc" provided that it is followed by three repetitions of "xyz" is
3176 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
3178 The <-- HERE shows in the regular expression about where the problem was
3181 =item Range iterator outside integer range
3183 (F) One (or both) of the numeric arguments to the range operator ".."
3184 are outside the range which can be represented by integers internally.
3185 One possible workaround is to force Perl to use magical string increment
3186 by prepending "0" to your numbers.
3188 =item readline() on closed filehandle %s
3190 (W closed) The filehandle you're reading from got itself closed sometime
3191 before now. Check your control flow.
3193 =item read() on closed filehandle %s
3195 (W closed) You tried to read from a closed filehandle.
3197 =item read() on unopened filehandle %s
3199 (W unopened) You tried to read from a filehandle that was never opened.
3201 =item Reallocation too large: %lx
3203 (F) You can't allocate more than 64K on an MS-DOS machine.
3205 =item realloc() of freed memory ignored
3207 (S malloc) An internal routine called realloc() on something that had
3210 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3212 (F debugging) You can't use the B<-D> option unless the code to produce
3213 the desired output is compiled into Perl, which entails some overhead,
3214 which is why it's currently left out of your copy.
3216 =item Recursive inheritance detected in package '%s'
3218 (F) More than 100 levels of inheritance were used. Probably indicates
3219 an unintended loop in your inheritance hierarchy.
3221 =item Recursive inheritance detected while looking for method %s
3223 (F) More than 100 levels of inheritance were encountered while invoking
3224 a method. Probably indicates an unintended loop in your inheritance
3227 =item Reference found where even-sized list expected
3229 (W misc) You gave a single reference where Perl was expecting a list
3230 with an even number of elements (for assignment to a hash). This usually
3231 means that you used the anon hash constructor when you meant to use
3232 parens. In any case, a hash requires key/value B<pairs>.
3234 %hash = { one => 1, two => 2, }; # WRONG
3235 %hash = [ qw/ an anon array / ]; # WRONG
3236 %hash = ( one => 1, two => 2, ); # right
3237 %hash = qw( one 1 two 2 ); # also fine
3239 =item Reference is already weak
3241 (W misc) You have attempted to weaken a reference that is already weak.
3242 Doing so has no effect.
3244 =item Reference miscount in sv_replace()
3246 (W internal) The internal sv_replace() function was handed a new SV with
3247 a reference count of other than 1.
3249 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
3251 (F) You used something like C<\7> in your regular expression, but there are
3252 not at least seven sets of capturing parentheses in the expression. If you
3253 wanted to have the character with value 7 inserted into the regular expression,
3254 prepend a zero to make the number at least two digits: C<\07>
3256 The <-- HERE shows in the regular expression about where the problem was
3259 =item regexp memory corruption
3261 (P) The regular expression engine got confused by what the regular
3262 expression compiler gave it.
3264 =item Regexp out of space
3266 (P) A "can't happen" error, because safemalloc() should have caught it
3269 =item Repeated format line will never terminate (~~ and @# incompatible)
3271 (F) Your format containes the ~~ repeat-until-blank sequence and a
3272 numeric field that will never go blank so that the repetition never
3273 terminates. You might use ^# instead. See L<perlform>.
3275 =item Reversed %s= operator
3277 (W syntax) You wrote your assignment operator backwards. The = must
3278 always comes last, to avoid ambiguity with subsequent unary operators.
3280 =item Runaway format
3282 (F) Your format contained the ~~ repeat-until-blank sequence, but it
3283 produced 200 lines at once, and the 200th line looked exactly like the
3284 199th line. Apparently you didn't arrange for the arguments to exhaust
3285 themselves, either by using ^ instead of @ (for scalar variables), or by
3286 shifting or popping (for array variables). See L<perlform>.
3288 =item Scalars leaked: %d
3290 (P) Something went wrong in Perl's internal bookkeeping of scalars:
3291 not all scalar variables were deallocated by the time Perl exited.
3292 What this usually indicates is a memory leak, which is of course bad,
3293 especially if the Perl program is intended to be long-running.
3295 =item Scalar value @%s[%s] better written as $%s[%s]
3297 (W syntax) You've used an array slice (indicated by @) to select a
3298 single element of an array. Generally it's better to ask for a scalar
3299 value (indicated by $). The difference is that C<$foo[&bar]> always
3300 behaves like a scalar, both when assigning to it and when evaluating its
3301 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
3302 and provides a list context to its subscript, which can do weird things
3303 if you're expecting only one subscript.
3305 On the other hand, if you were actually hoping to treat the array
3306 element as a list, you need to look into how references work, because
3307 Perl will not magically convert between scalars and lists for you. See
3310 =item Scalar value @%s{%s} better written as $%s{%s}
3312 (W syntax) You've used a hash slice (indicated by @) to select a single
3313 element of a hash. Generally it's better to ask for a scalar value
3314 (indicated by $). The difference is that C<$foo{&bar}> always behaves
3315 like a scalar, both when assigning to it and when evaluating its
3316 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
3317 and provides a list context to its subscript, which can do weird things
3318 if you're expecting only one subscript.
3320 On the other hand, if you were actually hoping to treat the hash element
3321 as a list, you need to look into how references work, because Perl will
3322 not magically convert between scalars and lists for you. See
3325 =item Script is not setuid/setgid in suidperl
3327 (F) Oddly, the suidperl program was invoked on a script without a setuid
3328 or setgid bit set. This doesn't make much sense.
3330 =item Search pattern not terminated
3332 (F) The lexer couldn't find the final delimiter of a // or m{}
3333 construct. Remember that bracketing delimiters count nesting level.
3334 Missing the leading C<$> from a variable C<$m> may cause this error.
3336 Note that since Perl 5.9.0 a // can also be the I<defined-or>
3337 construct, not just the empty search pattern. Therefore code written
3338 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
3339 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
3341 =item %sseek() on unopened filehandle
3343 (W unopened) You tried to use the seek() or sysseek() function on a
3344 filehandle that was either never opened or has since been closed.
3346 =item select not implemented
3348 (F) This machine doesn't implement the select() system call.
3350 =item Self-ties of arrays and hashes are not supported
3352 (F) Self-ties are of arrays and hashes are not supported in
3353 the current implementation.
3355 =item Semicolon seems to be missing
3357 (W semicolon) A nearby syntax error was probably caused by a missing
3358 semicolon, or possibly some other missing operator, such as a comma.
3360 =item semi-panic: attempt to dup freed string
3362 (S internal) The internal newSVsv() routine was called to duplicate a
3363 scalar that had previously been marked as free.
3365 =item sem%s not implemented
3367 (F) You don't have System V semaphore IPC on your system.
3369 =item send() on closed socket %s
3371 (W closed) The socket you're sending to got itself closed sometime
3372 before now. Check your control flow.
3374 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
3376 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
3377 shows in the regular expression about where the problem was discovered. See
3380 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
3382 (F) A proposed regular expression extension has the character reserved but
3383 has not yet been written. The <-- HERE shows in the regular expression about
3384 where the problem was discovered. See L<perlre>.
3386 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
3388 (F) You used a regular expression extension that doesn't make sense. The
3389 <-- HERE shows in the regular expression about where the problem was
3390 discovered. See L<perlre>.
3392 =item Sequence (?#... not terminated in regex; marked by <-- HERE in m/%s/
3394 (F) A regular expression comment must be terminated by a closing
3395 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
3396 the regular expression about where the problem was discovered. See
3399 =item Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/%s/
3401 (F) If the contents of a (?{...}) clause contains braces, they must balance
3402 for Perl to properly detect the end of the clause. The <-- HERE shows in
3403 the regular expression about where the problem was discovered. See
3406 =item 500 Server error
3412 This is the error message generally seen in a browser window when trying
3413 to run a CGI program (including SSI) over the web. The actual error text
3414 varies widely from server to server. The most frequently-seen variants
3415 are "500 Server error", "Method (something) not permitted", "Document
3416 contains no data", "Premature end of script headers", and "Did not
3417 produce a valid header".
3419 B<This is a CGI error, not a Perl error>.
3421 You need to make sure your script is executable, is accessible by the
3422 user CGI is running the script under (which is probably not the user
3423 account you tested it under), does not rely on any environment variables
3424 (like PATH) from the user it isn't running under, and isn't in a
3425 location where the CGI server can't find it, basically, more or less.
3426 Please see the following for more information:
3428 http://www.perl.org/CGI_MetaFAQ.html
3429 http://www.htmlhelp.org/faq/cgifaq.html
3430 http://www.w3.org/Security/Faq/
3432 You should also look at L<perlfaq9>.
3434 =item setegid() not implemented
3436 (F) You tried to assign to C<$)>, and your operating system doesn't
3437 support the setegid() system call (or equivalent), or at least Configure
3440 =item seteuid() not implemented
3442 (F) You tried to assign to C<< $> >>, and your operating system doesn't
3443 support the seteuid() system call (or equivalent), or at least Configure
3446 =item setpgrp can't take arguments
3448 (F) Your system has the setpgrp() from BSD 4.2, which takes no
3449 arguments, unlike POSIX setpgid(), which takes a process ID and process
3452 =item setrgid() not implemented
3454 (F) You tried to assign to C<$(>, and your operating system doesn't
3455 support the setrgid() system call (or equivalent), or at least Configure
3458 =item setruid() not implemented
3460 (F) You tried to assign to C<$<>, and your operating system doesn't
3461 support the setruid() system call (or equivalent), or at least Configure
3464 =item setsockopt() on closed socket %s
3466 (W closed) You tried to set a socket option on a closed socket. Did you
3467 forget to check the return value of your socket() call? See
3468 L<perlfunc/setsockopt>.
3470 =item Setuid/gid script is writable by world
3472 (F) The setuid emulator won't run a script that is writable by the
3473 world, because the world might have written on it already.
3475 =item shm%s not implemented
3477 (F) You don't have System V shared memory IPC on your system.
3479 =item !=~ should be !~
3481 (W syntax) The non-matching operator is !~, not !=~. !=~ will be
3482 interpreted as the != (numeric not equal) and ~ (1's complement)
3483 operators: probably not what you intended.
3485 =item <> should be quotes
3487 (F) You wrote C<< require <file> >> when you should have written
3490 =item /%s/ should probably be written as "%s"
3492 (W syntax) You have used a pattern where Perl expected to find a string,
3493 as in the first argument to C<join>. Perl will treat the true or false
3494 result of matching the pattern against $_ as the string, which is
3495 probably not what you had in mind.
3497 =item shutdown() on closed socket %s
3499 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
3502 =item SIG%s handler "%s" not defined
3504 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
3505 Perhaps you put it into the wrong package?
3507 =item sort is now a reserved word
3509 (F) An ancient error message that almost nobody ever runs into anymore.
3510 But before sort was a keyword, people sometimes used it as a filehandle.
3512 =item Sort subroutine didn't return a numeric value
3514 (F) A sort comparison routine must return a number. You probably blew
3515 it by not using C<< <=> >> or C<cmp>, or by not using them correctly.
3516 See L<perlfunc/sort>.
3518 =item Sort subroutine didn't return single value
3520 (F) A sort comparison subroutine may not return a list value with more
3521 or less than one element. See L<perlfunc/sort>.
3523 =item splice() offset past end of array
3525 (W misc) You attempted to specify an offset that was past the end of
3526 the array passed to splice(). Splicing will instead commence at the end
3527 of the array, rather than past it. If this isn't what you want, try
3528 explicitly pre-extending the array by assigning $#array = $offset. See
3533 (P) The split was looping infinitely. (Obviously, a split shouldn't
3534 iterate more times than there are characters of input, which is what
3535 happened.) See L<perlfunc/split>.
3537 =item Statement unlikely to be reached
3539 (W exec) You did an exec() with some statement after it other than a
3540 die(). This is almost always an error, because exec() never returns
3541 unless there was a failure. You probably wanted to use system()
3542 instead, which does return. To suppress this warning, put the exec() in
3545 =item stat() on unopened filehandle %s
3547 (W unopened) You tried to use the stat() function on a filehandle that
3548 was either never opened or has since been closed.
3550 =item Stub found while resolving method `%s' overloading %s
3552 (P) Overloading resolution over @ISA tree may be broken by importation
3553 stubs. Stubs should never be implicitly created, but explicit calls to
3554 C<can> may break this.
3556 =item Subroutine %s redefined
3558 (W redefine) You redefined a subroutine. To suppress this warning, say
3561 no warnings 'redefine';
3562 eval "sub name { ... }";
3565 =item Substitution loop
3567 (P) The substitution was looping infinitely. (Obviously, a substitution
3568 shouldn't iterate more times than there are characters of input, which
3569 is what happened.) See the discussion of substitution in
3570 L<perlop/"Quote and Quote-like Operators">.
3572 =item Substitution pattern not terminated
3574 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
3575 construct. Remember that bracketing delimiters count nesting level.
3576 Missing the leading C<$> from variable C<$s> may cause this error.
3578 =item Substitution replacement not terminated
3580 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
3581 construct. Remember that bracketing delimiters count nesting level.
3582 Missing the leading C<$> from variable C<$s> may cause this error.
3584 =item substr outside of string
3586 (W substr),(F) You tried to reference a substr() that pointed outside of
3587 a string. That is, the absolute value of the offset was larger than the
3588 length of the string. See L<perlfunc/substr>. This warning is fatal if
3589 substr is used in an lvalue context (as the left hand side of an
3590 assignment or as a subroutine argument for example).
3592 =item suidperl is no longer needed since %s
3594 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but
3595 a version of the setuid emulator somehow got run anyway.
3597 =item Switch (?(condition)... contains too many branches in regex; marked by <-- HERE in m/%s/
3599 (F) A (?(condition)if-clause|else-clause) construct can have at most two
3600 branches (the if-clause and the else-clause). If you want one or both to
3601 contain alternation, such as using C<this|that|other>, enclose it in
3602 clustering parentheses:
3604 (?(condition)(?:this|that|other)|else-clause)
3606 The <-- HERE shows in the regular expression about where the problem was
3607 discovered. See L<perlre>.
3609 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
3611 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
3612 number, it can be only a number. The <-- HERE shows in the regular expression
3613 about where the problem was discovered. See L<perlre>.
3615 =item switching effective %s is not implemented
3617 (F) While under the C<use filetest> pragma, we cannot switch the real
3618 and effective uids or gids.
3622 (F) The final summary message when a C<perl -c> succeeds.
3626 (F) Probably means you had a syntax error. Common reasons include:
3628 A keyword is misspelled.
3629 A semicolon is missing.
3631 An opening or closing parenthesis is missing.
3632 An opening or closing brace is missing.
3633 A closing quote is missing.
3635 Often there will be another error message associated with the syntax
3636 error giving more information. (Sometimes it helps to turn on B<-w>.)
3637 The error message itself often tells you where it was in the line when
3638 it decided to give up. Sometimes the actual error is several tokens
3639 before this, because Perl is good at understanding random input.
3640 Occasionally the line number may be misleading, and once in a blue moon
3641 the only way to figure out what's triggering the error is to call
3642 C<perl -c> repeatedly, chopping away half the program each time to see
3643 if the error went away. Sort of the cybernetic version of S<20
3646 =item syntax error at line %d: `%s' unexpected
3648 (A) You've accidentally run your script through the Bourne shell instead
3649 of Perl. Check the #! line, or manually feed your script into Perl
3652 =item syntax error in file %s at line %d, next 2 tokens "%s"
3654 (F) This error is likely to occur if you run a perl5 script through
3655 a perl4 interpreter, especially if the next 2 tokens are "use strict"
3656 or "my $var" or "our $var".
3658 =item sysread() on closed filehandle %s
3660 (W closed) You tried to read from a closed filehandle.
3662 =item sysread() on unopened filehandle %s
3664 (W unopened) You tried to read from a filehandle that was never opened.
3666 =item System V %s is not implemented on this machine
3668 (F) You tried to do something with a function beginning with "sem",
3669 "shm", or "msg" but that System V IPC is not implemented in your
3670 machine. In some machines the functionality can exist but be
3671 unconfigured. Consult your system support.
3673 =item syswrite() on closed filehandle %s
3675 (W closed) The filehandle you're writing to got itself closed sometime
3676 before now. Check your control flow.
3678 =item C<-T> and C<-B> not implemented on filehandles
3680 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
3681 know about your kind of stdio. You'll have to use a filename instead.
3683 =item Target of goto is too deeply nested
3685 (F) You tried to use C<goto> to reach a label that was too deeply nested
3686 for Perl to reach. Perl is doing you a favor by refusing.
3688 =item tell() on unopened filehandle
3690 (W unopened) You tried to use the tell() function on a filehandle that
3691 was either never opened or has since been closed.
3693 =item That use of $[ is unsupported
3695 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
3696 as a compiler directive. You may say only one of
3705 This is to prevent the problem of one module changing the array base out
3706 from under another module inadvertently. See L<perlvar/$[>.
3708 =item The crypt() function is unimplemented due to excessive paranoia
3710 (F) Configure couldn't find the crypt() function on your machine,
3711 probably because your vendor didn't supply it, probably because they
3712 think the U.S. Government thinks it's a secret, or at least that they
3713 will continue to pretend that it is. And if you quote me on that, I
3716 =item The %s function is unimplemented
3718 The function indicated isn't implemented on this architecture, according
3719 to the probings of Configure.
3721 =item The stat preceding %s wasn't an lstat
3723 (F) It makes no sense to test the current stat buffer for symbolic
3724 linkhood if the last stat that wrote to the stat buffer already went
3725 past the symlink to get to the real file. Use an actual filename
3728 =item The 'unique' attribute may only be applied to 'our' variables
3730 (F) Currently this attribute is not supported on C<my> or C<sub>
3731 declarations. See L<perlfunc/our>.
3733 =item This Perl can't reset CRTL environ elements (%s)
3735 =item This Perl can't set CRTL environ elements (%s=%s)
3737 (W internal) Warnings peculiar to VMS. You tried to change or delete an
3738 element of the CRTL's internal environ array, but your copy of Perl
3739 wasn't built with a CRTL that contained the setenv() function. You'll
3740 need to rebuild Perl with a CRTL that does, or redefine
3741 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
3742 target of the change to
3743 %ENV which produced the warning.
3745 =item thread failed to start: %s
3747 (F) The entry point function of threads->create() failed for some reason.
3749 =item Tied variable freed while still in use
3751 (F) An access method for a tied variable (e.g. FETCH) did something to
3752 free the variable. Since continuing the current operation is likely
3753 to result in a coredump, Perl is bailing out instead.
3755 =item times not implemented
3757 (F) Your version of the C library apparently doesn't do times(). I
3758 suspect you're not running on Unix.
3760 =item To%s: illegal mapping '%s'
3762 (F) You tried to define a customized To-mapping for lc(), lcfirst,
3763 uc(), or ucfirst() (or their string-inlined versions), but you
3764 specified an illegal mapping.
3765 See L<perlunicode/"User-Defined Character Properties">.
3767 =item Too deeply nested ()-groups
3769 (F) Your template contains ()-groups with a ridiculously deep nesting level.
3771 =item Too few args to syscall
3773 (F) There has to be at least one argument to syscall() to specify the
3774 system call to call, silly dilly.
3776 =item Too late for "-%s" option
3778 (X) The #! line (or local equivalent) in a Perl script contains the
3779 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
3780 are not intended for use inside scripts. Use the C<use> pragma instead.
3782 =item Too late for "B<-T>" option
3784 (X) The #! line (or local equivalent) in a Perl script contains the
3785 B<-T> option, but Perl was not invoked with B<-T> in its command line.
3786 This is an error because, by the time Perl discovers a B<-T> in a
3787 script, it's too late to properly taint everything from the environment.
3790 If the Perl script is being executed as a command using the #!
3791 mechanism (or its local equivalent), this error can usually be fixed by
3792 editing the #! line so that the B<-T> option is a part of Perl's first
3793 argument: e.g. change C<perl -n -T> to C<perl -T -n>.
3795 If the Perl script is being executed as C<perl scriptname>, then the
3796 B<-T> option must appear on the command line: C<perl -T scriptname>.
3798 =item Too late to run %s block
3800 (W void) A CHECK or INIT block is being defined during run time proper,
3801 when the opportunity to run them has already passed. Perhaps you are
3802 loading a file with C<require> or C<do> when you should be using C<use>
3803 instead. Or perhaps you should put the C<require> or C<do> inside a
3806 =item Too many args to syscall
3808 (F) Perl supports a maximum of only 14 args to syscall().
3810 =item Too many arguments for %s
3812 (F) The function requires fewer arguments than you specified.
3816 (A) You've accidentally run your script through B<csh> instead of Perl.
3817 Check the #! line, or manually feed your script into Perl yourself.
3821 (A) You've accidentally run your script through B<csh> instead of Perl.
3822 Check the #! line, or manually feed your script into Perl yourself.
3824 =item Trailing \ in regex m/%s/
3826 (F) The regular expression ends with an unbackslashed backslash.
3827 Backslash it. See L<perlre>.
3829 =item Transliteration pattern not terminated
3831 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
3832 or y/// or y[][] construct. Missing the leading C<$> from variables
3833 C<$tr> or C<$y> may cause this error.
3835 =item Transliteration replacement not terminated
3837 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
3840 =item '%s' trapped by operation mask
3842 (F) You tried to use an operator from a Safe compartment in which it's
3843 disallowed. See L<Safe>.
3845 =item truncate not implemented
3847 (F) Your machine doesn't implement a file truncation mechanism that
3848 Configure knows about.
3850 =item Type of arg %d to %s must be %s (not %s)
3852 (F) This function requires the argument in that position to be of a
3853 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
3854 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
3855 {EXPR} forms as an explicit dereference. See L<perlref>.
3857 =item umask not implemented
3859 (F) Your machine doesn't implement the umask function and you tried to
3860 use it to restrict permissions for yourself (EXPR & 0700).
3862 =item Unable to create sub named "%s"
3864 (F) You attempted to create or access a subroutine with an illegal name.
3866 =item Unbalanced context: %d more PUSHes than POPs
3868 (W internal) The exit code detected an internal inconsistency in how
3869 many execution contexts were entered and left.
3871 =item Unbalanced saves: %d more saves than restores
3873 (W internal) The exit code detected an internal inconsistency in how
3874 many values were temporarily localized.
3876 =item Unbalanced scopes: %d more ENTERs than LEAVEs
3878 (W internal) The exit code detected an internal inconsistency in how
3879 many blocks were entered and left.
3881 =item Unbalanced tmps: %d more allocs than frees
3883 (W internal) The exit code detected an internal inconsistency in how
3884 many mortal scalars were allocated and freed.
3886 =item Undefined format "%s" called
3888 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3889 another package? See L<perlform>.
3891 =item Undefined sort subroutine "%s" called
3893 (F) The sort comparison routine specified doesn't seem to exist.
3894 Perhaps it's in a different package? See L<perlfunc/sort>.
3896 =item Undefined subroutine &%s called
3898 (F) The subroutine indicated hasn't been defined, or if it was, it has
3899 since been undefined.
3901 =item Undefined subroutine called
3903 (F) The anonymous subroutine you're trying to call hasn't been defined,
3904 or if it was, it has since been undefined.
3906 =item Undefined subroutine in sort
3908 (F) The sort comparison routine specified is declared but doesn't seem
3909 to have been defined yet. See L<perlfunc/sort>.
3911 =item Undefined top format "%s" called
3913 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3914 another package? See L<perlform>.
3916 =item Undefined value assigned to typeglob
3918 (W misc) An undefined value was assigned to a typeglob, a la
3919 C<*foo = undef>. This does nothing. It's possible that you really mean
3922 =item %s: Undefined variable
3924 (A) You've accidentally run your script through B<csh> instead of Perl.
3925 Check the #! line, or manually feed your script into Perl yourself.
3927 =item unexec of %s into %s failed!
3929 (F) The unexec() routine failed for some reason. See your local FSF
3930 representative, who probably put it there in the first place.
3932 =item Unicode character %s is illegal
3934 (W utf8) Certain Unicode characters have been designated off-limits by
3935 the Unicode standard and should not be generated. If you really know
3936 what you are doing you can turn off this warning by C<no warnings 'utf8';>.
3938 =item Unknown BYTEORDER
3940 (F) There are no byte-swapping functions for a machine with this byte
3943 =item Unknown open() mode '%s'
3945 (F) The second argument of 3-argument open() is not among the list
3946 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
3947 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
3949 =item Unknown PerlIO layer "%s"
3951 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
3952 system. (Layers take care of transforming data between external and
3953 internal representations.) Note that some layers, such as C<mmap>,
3954 are not supported in all environments. If your program didn't
3955 explicitly request the failing operation, it may be the result of the
3956 value of the environment variable PERLIO.
3958 =item Unknown process %x sent message to prime_env_iter: %s
3960 (P) An error peculiar to VMS. Perl was reading values for %ENV before
3961 iterating over it, and someone else stuck a message in the stream of
3962 data Perl expected. Someone's very confused, or perhaps trying to
3963 subvert Perl's population of %ENV for nefarious purposes.
3965 =item Unknown "re" subpragma '%s' (known ones are: %s)
3967 You tried to use an unknown subpragma of the "re" pragma.
3969 =item Unknown switch condition (?(%.2s in regex; marked by <-- HERE in m/%s/
3971 (F) The condition part of a (?(condition)if-clause|else-clause) construct
3972 is not known. The condition may be lookahead or lookbehind (the condition
3973 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
3974 condition is true if the code evaluates to a true value), or a number (the
3975 condition is true if the set of capturing parentheses named by the number
3978 The <-- HERE shows in the regular expression about where the problem was
3979 discovered. See L<perlre>.
3981 =item Unknown Unicode option letter '%c'
3983 You specified an unknown Unicode option. See L<perlrun> documentation
3984 of the C<-C> switch for the list of known options.
3986 =item Unknown Unicode option value %x
3988 You specified an unknown Unicode option. See L<perlrun> documentation
3989 of the C<-C> switch for the list of known options.
3991 =item Unknown warnings category '%s'
3993 (F) An error issued by the C<warnings> pragma. You specified a warnings
3994 category that is unknown to perl at this point.
3996 Note that if you want to enable a warnings category registered by a module
3997 (e.g. C<use warnings 'File::Find'>), you must have imported this module
4000 =item unmatched [ in regex; marked by <-- HERE in m/%s/
4002 (F) The brackets around a character class must match. If you wish to
4003 include a closing bracket in a character class, backslash it or put it
4004 first. The <-- HERE shows in the regular expression about where the problem
4005 was discovered. See L<perlre>.
4007 =item unmatched ( in regex; marked by <-- HERE in m/%s/
4009 (F) Unbackslashed parentheses must always be balanced in regular
4010 expressions. If you're a vi user, the % key is valuable for finding the
4011 matching parenthesis. The <-- HERE shows in the regular expression about
4012 where the problem was discovered. See L<perlre>.
4014 =item Unmatched right %s bracket
4016 (F) The lexer counted more closing curly or square brackets than opening
4017 ones, so you're probably missing a matching opening bracket. As a
4018 general rule, you'll find the missing one (so to speak) near the place
4019 you were last editing.
4021 =item Unquoted string "%s" may clash with future reserved word
4023 (W reserved) You used a bareword that might someday be claimed as a
4024 reserved word. It's best to put such a word in quotes, or capitalize it
4025 somehow, or insert an underbar into it. You might also declare it as a
4028 =item Unrecognized character %s
4030 (F) The Perl parser has no idea what to do with the specified character
4031 in your Perl script (or eval). Perhaps you tried to run a compressed
4032 script, a binary program, or a directory as a Perl program.
4034 =item /%s/: Unrecognized escape \\%c in character class passed through
4036 (W regexp) You used a backslash-character combination which is not
4037 recognized by Perl inside character classes. The character was
4038 understood literally.
4040 =item Unrecognized escape \\%c passed through
4042 (W misc) You used a backslash-character combination which is not
4045 =item Unrecognized escape \\%c passed through in regex; marked by <-- HERE in m/%s/
4047 (W regexp) You used a backslash-character combination which is not
4048 recognized by Perl. This combination appears in an interpolated variable or
4049 a C<'>-delimited regular expression. The character was understood
4050 literally. The <-- HERE shows in the regular expression about where the
4051 escape was discovered.
4053 =item Unrecognized signal name "%s"
4055 (F) You specified a signal name to the kill() function that was not
4056 recognized. Say C<kill -l> in your shell to see the valid signal names
4059 =item Unrecognized switch: -%s (-h will show valid options)
4061 (F) You specified an illegal option to Perl. Don't do that. (If you
4062 think you didn't do that, check the #! line to see if it's supplying the
4063 bad switch on your behalf.)
4065 =item Unsuccessful %s on filename containing newline
4067 (W newline) A file operation was attempted on a filename, and that
4068 operation failed, PROBABLY because the filename contained a newline,
4069 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
4071 =item Unsupported directory function "%s" called
4073 (F) Your machine doesn't support opendir() and readdir().
4075 =item Unsupported function %s
4077 (F) This machine doesn't implement the indicated function, apparently.
4078 At least, Configure doesn't think so.
4080 =item Unsupported function fork
4082 (F) Your version of executable does not support forking.
4084 Note that under some systems, like OS/2, there may be different flavors
4085 of Perl executables, some of which may support fork, some not. Try
4086 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
4088 =item Unsupported script encoding %s
4090 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
4091 declares it to be in a Unicode encoding that Perl cannot read.
4093 =item Unsupported socket function "%s" called
4095 (F) Your machine doesn't support the Berkeley socket mechanism, or at
4096 least that's what Configure thought.
4098 =item Unterminated attribute list
4100 (F) The lexer found something other than a simple identifier at the
4101 start of an attribute, and it wasn't a semicolon or the start of a
4102 block. Perhaps you terminated the parameter list of the previous
4103 attribute too soon. See L<attributes>.
4105 =item Unterminated attribute parameter in attribute list
4107 (F) The lexer saw an opening (left) parenthesis character while parsing
4108 an attribute list, but the matching closing (right) parenthesis
4109 character was not found. You may need to add (or remove) a backslash
4110 character to get your parentheses to balance. See L<attributes>.
4112 =item Unterminated compressed integer
4114 (F) An argument to unpack("w",...) was incompatible with the BER
4115 compressed integer format and could not be converted to an integer.
4116 See L<perlfunc/pack>.
4118 =item Unterminated <> operator
4120 (F) The lexer saw a left angle bracket in a place where it was expecting
4121 a term, so it's looking for the corresponding right angle bracket, and
4122 not finding it. Chances are you left some needed parentheses out
4123 earlier in the line, and you really meant a "less than".
4125 =item untie attempted while %d inner references still exist
4127 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
4128 still valid when C<untie> was called.
4130 =item Usage: POSIX::%s(%s)
4132 (F) You called a POSIX function with incorrect arguments.
4133 See L<POSIX/FUNCTIONS> for more information.
4135 =item Usage: Win32::%s(%s)
4137 (F) You called a Win32 function with incorrect arguments.
4138 See L<Win32> for more information.
4140 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in m/%s/
4142 (W regexp) You have used an internal modifier such as (?-o) that has no
4143 meaning unless removed from the entire regexp:
4145 if ($string =~ /(?-o)$pattern/o) { ... }
4149 if ($string =~ /$pattern/) { ... }
4151 The <-- HERE shows in the regular expression about
4152 where the problem was discovered. See L<perlre>.
4154 =item Useless localization of %s
4156 (W syntax) The localization of lvalues such as C<local($x=10)> is
4157 legal, but in fact the local() currently has no effect. This may change at
4158 some point in the future, but in the meantime such code is discouraged.
4160 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
4162 (W regexp) You have used an internal modifier such as (?o) that has no
4163 meaning unless applied to the entire regexp:
4165 if ($string =~ /(?o)$pattern/) { ... }
4169 if ($string =~ /$pattern/o) { ... }
4171 The <-- HERE shows in the regular expression about
4172 where the problem was discovered. See L<perlre>.
4174 =item Useless use of %s in void context
4176 (W void) You did something without a side effect in a context that does
4177 nothing with the return value, such as a statement that doesn't return a
4178 value from a block, or the left side of a scalar comma operator. Very
4179 often this points not to stupidity on your part, but a failure of Perl
4180 to parse your program the way you thought it would. For example, you'd
4181 get this if you mixed up your C precedence with Python precedence and
4186 when you meant to say
4188 ($one, $two) = (1, 2);
4190 Another common error is to use ordinary parentheses to construct a list
4191 reference when you should be using square or curly brackets, for
4196 when you should have said
4200 The square brackets explicitly turn a list value into a scalar value,
4201 while parentheses do not. So when a parenthesized list is evaluated in
4202 a scalar context, the comma is treated like C's comma operator, which
4203 throws away the left argument, which is not what you want. See
4204 L<perlref> for more on this.
4206 This warning will not be issued for numerical constants equal to 0 or 1
4207 since they are often used in statements like
4209 1 while sub_with_side_effects() ;
4211 String constants that would normally evaluate to 0 or 1 are warned
4214 =item Useless use of "re" pragma
4216 (W) You did C<use re;> without any arguments. That isn't very useful.
4218 =item Useless use of sort in scalar context
4220 (W void) You used sort in scalar context, as in :
4224 This is not very useful, and perl currently optimizes this away.
4226 =item Useless use of %s with no values
4228 (W syntax) You used the push() or unshift() function with no arguments
4229 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
4230 usually have any effect on the array, so is completely useless. It's
4231 possible in principle that push(@tied_array) could have some effect
4232 if the array is tied to a class which implements a PUSH method. If so,
4233 you can write it as C<push(@tied_array,())> to avoid this warning.
4235 =item "use" not allowed in expression
4237 (F) The "use" keyword is recognized and executed at compile time, and
4238 returns no useful value. See L<perlmod>.
4240 =item Use of bare << to mean <<"" is deprecated
4242 (D deprecated) You are now encouraged to use the explicitly quoted form
4243 if you wish to use an empty line as the terminator of the here-document.
4245 =item Use of chdir('') or chdir(undef) as chdir() deprecated
4247 (D deprecated) chdir() with no arguments is documented to change to
4248 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
4249 behavior, but that has been deprecated. In future versions they
4252 Be careful to check that what you pass to chdir() is defined and not
4253 blank, else you might find yourself in your home directory.
4255 =item Use of /c modifier is meaningless in s///
4257 (W regexp) You used the /c modifier in a substitution. The /c
4258 modifier is not presently meaningful in substitutions.
4260 =item Use of /c modifier is meaningless without /g
4262 (W regexp) You used the /c modifier with a regex operand, but didn't
4263 use the /g modifier. Currently, /c is meaningful only when /g is
4264 used. (This may change in the future.)
4266 =item Use of freed value in iteration
4268 (F) Perhaps you modified the iterated array within the loop?
4269 This error is typically caused by code like the following:
4272 @a = () for (1,2,@a);
4274 You are not supposed to modify arrays while they are being iterated over.
4275 For speed and efficiency reasons, Perl internally does not do full
4276 reference-counting of iterated items, hence deleting such an item in the
4277 middle of an iteration causes Perl to see a freed value.
4279 =item Use of *glob{FILEHANDLE} is deprecated
4281 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
4282 to access the filehandle slot within a typeglob.
4284 =item Use of /g modifier is meaningless in split
4286 (W regexp) You used the /g modifier on the pattern for a C<split>
4287 operator. Since C<split> always tries to match the pattern
4288 repeatedly, the C</g> has no effect.
4290 =item Use of implicit split to @_ is deprecated
4292 (D deprecated) It makes a lot of work for the compiler when you clobber
4293 a subroutine's argument list, so it's better if you assign the results
4294 of a split() explicitly to an array (or list).
4296 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
4298 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
4299 are looked up as methods (using the C<@ISA> hierarchy) even when the
4300 subroutines to be autoloaded were called as plain functions (e.g.
4301 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
4304 This bug will be rectified in future by using method lookup only for
4305 methods' C<AUTOLOAD>s. However, there is a significant base of existing
4306 code that may be using the old behavior. So, as an interim step, Perl
4307 currently issues an optional warning when non-methods use inherited
4310 The simple rule is: Inheritance will not work when autoloading
4311 non-methods. The simple fix for old code is: In any module that used
4312 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
4313 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
4316 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
4317 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
4318 C<use AutoLoader 'AUTOLOAD';>.
4320 =item Use of %s in printf format not supported
4322 (F) You attempted to use a feature of printf that is accessible from
4323 only C. This usually means there's a better way to do it in Perl.
4325 =item Use of $# is deprecated
4327 (D deprecated) This was an ill-advised attempt to emulate a poorly
4328 defined B<awk> feature. Use an explicit printf() or sprintf() instead.
4330 =item Use of %s is deprecated
4332 (D deprecated) The construct indicated is no longer recommended for use,
4333 generally because there's a better way to do it, and also because the
4334 old way has bad side effects.
4336 =item Use of -l on filehandle %s
4338 (W io) A filehandle represents an opened file, and when you opened the file
4339 it already went past any symlink you are presumably trying to look for.
4340 The operation returned C<undef>. Use a filename instead.
4342 =item Deprecated use of my() in false conditional
4344 (D deprecated) You used a declaration similar to C<my $x if 0>.
4345 There has been a long-standing bug in Perl that causes a lexical variable
4346 not to be cleared at scope exit when its declaration includes a false
4347 conditional. Some people have exploited this bug to achieve a kind of
4348 static variable. Since we intend to fix this bug, we don't want people
4349 relying on this behavior. You can achieve a similar static effect by
4350 declaring the variable in a separate block outside the function, eg
4352 sub f { my $x if 0; return $x++ }
4356 { my $x; sub f { return $x++ } }
4358 =item Use of "package" with no arguments is deprecated
4360 (D deprecated) You used the C<package> keyword without specifying a package
4361 name. So no namespace is current at all. Using this can cause many
4362 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
4365 =item Use of reference "%s" as array index
4367 (W misc) You tried to use a reference as an array index; this probably
4368 isn't what you mean, because references in numerical context tend
4369 to be huge numbers, and so usually indicates programmer error.
4371 If you really do mean it, explicitly numify your reference, like so:
4372 C<$array[0+$ref]>. This warning is not given for overloaded objects,
4373 either, because you can overload the numification and stringification
4374 operators and then you assumedly know what you are doing.
4376 =item Use of reserved word "%s" is deprecated
4378 (D deprecated) The indicated bareword is a reserved word. Future
4379 versions of perl may use it as a keyword, so you're better off either
4380 explicitly quoting the word in a manner appropriate for its context of
4381 use, or using a different name altogether. The warning can be
4382 suppressed for subroutine names by either adding a C<&> prefix, or using
4383 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
4385 =item Use of tainted arguments in %s is deprecated
4387 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
4388 arguments and at least one of them is tainted. This used to be allowed
4389 but will become a fatal error in a future version of perl. Untaint your
4390 arguments. See L<perlsec>.
4392 =item Use of uninitialized value%s
4394 (W uninitialized) An undefined value was used as if it were already
4395 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
4396 To suppress this warning assign a defined value to your variables.
4398 To help you figure out what was undefined, perl will try to tell you the
4399 name of the variable (if any) that was undefined. In some cases it cannot
4400 do this, so it also tells you what operation you used the undefined value
4401 in. Note, however, that perl optimizes your program and the operation
4402 displayed in the warning may not necessarily appear literally in your
4403 program. For example, C<"that $foo"> is usually optimized into C<"that "
4404 . $foo>, and the warning will refer to the C<concatenation (.)> operator,
4405 even though there is no C<.> in your program.
4407 =item Using a hash as a reference is deprecated
4409 (D deprecated) You tried to use a hash as a reference, as in
4410 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
4411 used to allow this syntax, but shouldn't have. It is now deprecated, and will
4412 be removed in a future version.
4414 =item Using an array as a reference is deprecated
4416 (D deprecated) You tried to use an array as a reference, as in
4417 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
4418 allow this syntax, but shouldn't have. It is now deprecated, and will be
4419 removed in a future version.
4421 =item UTF-16 surrogate %s
4423 (W utf8) You tried to generate half of an UTF-16 surrogate by
4424 requesting a Unicode character between the code points 0xD800 and
4425 0xDFFF (inclusive). That range is reserved exclusively for the use of
4426 UTF-16 encoding (by having two 16-bit UCS-2 characters); but Perl
4427 encodes its characters in UTF-8, so what you got is a very illegal
4428 character. If you really know what you are doing you can turn off
4429 this warning by C<no warnings 'utf8';>.
4431 =item Value of %s can be "0"; test with defined()
4433 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
4434 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
4435 can return a value of "0"; that would make the conditional expression
4436 false, which is probably not what you intended. When using these
4437 constructs in conditional expressions, test their values with the
4438 C<defined> operator.
4440 =item Value of CLI symbol "%s" too long
4442 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
4443 %ENV element from a CLI symbol table, and found a resultant string
4444 longer than 1024 characters. The return value has been truncated to
4447 =item Variable "%s" is not available
4449 (W closure) During compilation, an inner named subroutine or eval is
4450 attempting to capture an outer lexical that is not currently available.
4451 This can happen for one of two reasons. First, the outer lexical may be
4452 declared in an outer anonymous subroutine that has not yet been created.
4453 (Remember that named subs are created at compile time, while anonymous
4454 subs are created at run-time.) For example,
4456 sub { my $a; sub f { $a } }
4458 At the time that f is created, it can't capture the current value of $a,
4459 since the anonymous subroutine hasn't been created yet. Conversely,
4460 the following won't give a warning since the anonymous subroutine has by
4461 now been created and is live:
4463 sub { my $a; eval 'sub f { $a }' }->();
4465 The second situation is caused by an eval accessing a variable that has
4466 gone out of scope, for example,
4474 Here, when the '$a' in the eval is being compiled, f() is not currently being
4475 executed, so its $a is not available for capture.
4477 =item Variable "%s" is not imported%s
4479 (F) While "use strict" in effect, you referred to a global variable that
4480 you apparently thought was imported from another module, because
4481 something else of the same name (usually a subroutine) is exported by
4482 that module. It usually means you put the wrong funny character on the
4483 front of your variable.
4485 =item Variable length lookbehind not implemented in regex; marked by <-- HERE in m/%s/
4487 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
4488 known at compile time. The <-- HERE shows in the regular expression about
4489 where the problem was discovered. See L<perlre>.
4491 =item "%s" variable %s masks earlier declaration in same %s
4493 (W misc) A "my" or "our" variable has been redeclared in the current
4494 scope or statement, effectively eliminating all access to the previous
4495 instance. This is almost always a typographical error. Note that the
4496 earlier variable will still exist until the end of the scope or until
4497 all closure referents to it are destroyed.
4499 =item Variable syntax
4501 (A) You've accidentally run your script through B<csh> instead
4502 of Perl. Check the #! line, or manually feed your script into
4505 =item Variable "%s" will not stay shared
4507 (W closure) An inner (nested) I<named> subroutine is referencing a
4508 lexical variable defined in an outer named subroutine.
4510 When the inner subroutine is called, it will see the value of
4511 the outer subroutine's variable as it was before and during the *first*
4512 call to the outer subroutine; in this case, after the first call to the
4513 outer subroutine is complete, the inner and outer subroutines will no
4514 longer share a common value for the variable. In other words, the
4515 variable will no longer be shared.
4517 This problem can usually be solved by making the inner subroutine
4518 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
4519 reference variables in outer subroutines are created, they
4520 are automatically rebound to the current values of such variables.
4522 =item Version number must be a constant number
4524 (P) The attempt to translate a C<use Module n.n LIST> statement into
4525 its equivalent C<BEGIN> block found an internal inconsistency with
4528 =item v-string in use/require is non-portable
4530 (W portable) The use of v-strings is non-portable to older, pre-5.6, Perls.
4531 If you want your scripts to be backward portable, use the floating
4532 point version number: for example, instead of C<use 5.6.1> say
4533 C<use 5.006_001>. This of course won't help: the older Perls
4534 won't suddenly start understanding newer features, but at least
4535 they will show a sensible error message indicating the required
4538 =item Warning: something's wrong
4540 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
4541 you called it with no args and C<$_> was empty.
4543 =item Warning: unable to close filehandle %s properly
4545 (S) The implicit close() done by an open() got an error indication on
4546 the close(). This usually indicates your file system ran out of disk
4549 =item Warning: Use of "%s" without parentheses is ambiguous
4551 (S ambiguous) You wrote a unary operator followed by something that
4552 looks like a binary operator that could also have been interpreted as a
4553 term or unary operator. For instance, if you know that the rand
4554 function has a default argument of 1.0, and you write
4558 you may THINK you wrote the same thing as
4562 but in actual fact, you got
4566 So put in parentheses to say what you really mean.
4568 =item Wide character in %s
4570 (W utf8) Perl met a wide character (>255) when it wasn't expecting
4571 one. This warning is by default on for I/O (like print). The easiest
4572 way to quiet this warning is simply to add the C<:utf8> layer to the
4573 output, e.g. C<binmode STDOUT, ':utf8'>. Another way to turn off the
4574 warning is to add C<no warnings 'utf8';> but that is often closer to
4575 cheating. In general, you are supposed to explicitly mark the
4576 filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
4578 =item Within []-length '%c' not allowed
4580 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
4581 C<TEMPLATE> always matches the same amount of packed bytes that can be
4582 determined from the template alone. This is not possible if it contains an
4583 of the codes @, /, U, u, w or a *-length. Redesign the template.
4585 =item write() on closed filehandle %s
4587 (W closed) The filehandle you're writing to got itself closed sometime
4588 before now. Check your control flow.
4590 =item %s "\x%s" does not map to Unicode
4592 When reading in different encodings Perl tries to map everything
4593 into Unicode characters. The bytes you read in are not legal in
4594 this encoding, for example
4596 utf8 "\xE4" does not map to Unicode
4598 if you try to read in the a-diaereses Latin-1 as UTF-8.
4600 =item 'X' outside of string
4602 (F) You had a (un)pack template that specified a relative position before
4603 the beginning of the string being (un)packed. See L<perlfunc/pack>.
4605 =item 'x' outside of string in unpack
4607 (F) You had a pack template that specified a relative position after
4608 the end of the string being unpacked. See L<perlfunc/pack>.
4610 =item Xsub "%s" called in sort
4612 (F) The use of an external subroutine as a sort comparison is not yet
4615 =item Xsub called in sort
4617 (F) The use of an external subroutine as a sort comparison is not yet
4620 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
4622 (F) And you probably never will, because you probably don't have the
4623 sources to your kernel, and your vendor probably doesn't give a rip
4624 about what you want. Your best bet is to put a setuid C wrapper around
4627 =item You need to quote "%s"
4629 (W syntax) You assigned a bareword as a signal handler name.
4630 Unfortunately, you already have a subroutine of that name declared,
4631 which means that Perl 5 will try to call the subroutine when the
4632 assignment is executed, which is probably not what you want. (If it IS
4633 what you want, put an & in front.)
4635 =item Your random numbers are not that random
4637 (F) When trying to initialise the random seed for hashes, Perl could
4638 not get any randomness out of your system. This usually indicates
4639 Something Very Wrong.