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<$SIG{__WARN__}>
27 to a reference to a routine that will be called on each warning instead
28 of printing it. See L<perlvar>.
30 Default warnings are always enabled unless they are explicitly disabled
31 with the C<warnings> pragma or the B<-X> switch.
33 Trappable errors may be trapped using the eval operator. See
34 L<perlfunc/eval>. In almost all cases, warnings may be selectively
35 disabled or promoted to fatal errors using the C<warnings> pragma.
38 The messages are in alphabetical order, without regard to upper or
39 lower-case. Some of these messages are generic. Spots that vary are
40 denoted with a %s or other printf-style escape. These escapes are
41 ignored by the alphabetical order, as are all characters other than
42 letters. To look up your message, just ignore anything that is not a
47 =item accept() on closed socket %s
49 (W closed) You tried to do an accept on a closed socket. Did you forget
50 to check the return value of your socket() call? See
53 =item Allocation too large: %lx
55 (X) You can't allocate more than 64K on an MS-DOS machine.
57 =item '!' allowed only after types %s
59 (F) The '!' is allowed in pack() or unpack() only after certain types.
62 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
64 (W ambiguous) A subroutine you have declared has the same name as a Perl
65 keyword, and you have used the name without qualification for calling
66 one or the other. Perl decided to call the builtin because the
67 subroutine is not imported.
69 To force interpretation as a subroutine call, either put an ampersand
70 before the subroutine name, or qualify the name with its package.
71 Alternatively, you can import the subroutine (or pretend that it's
72 imported with the C<use subs> pragma).
74 To silently interpret it as the Perl operator, use the C<CORE::> prefix
75 on the operator (e.g. C<CORE::log($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 Array @%s missing the @ in argument %d of %s()
168 (D deprecated) Really old Perl let you omit the @ on array names in some
169 spots. This is now heavily deprecated.
171 =item assertion botched: %s
173 (P) The malloc package that comes with Perl had an internal failure.
175 =item Assertion failed: file "%s"
177 (P) A general assertion failed. The file in question must be examined.
179 =item Assignment to both a list and a scalar
181 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
182 must either both be scalars or both be lists. Otherwise Perl won't
183 know which context to supply to the right side.
185 =item A thread exited while %d threads were running
187 (W) When using threaded Perl, a thread (not necessarily the main
188 thread) exited while there were still other threads running.
189 Usually it's a good idea to first collect the return values of the
190 created threads by joining them, and only then exit from the main
191 thread. See L<threads>.
193 =item Attempt to access disallowed key '%s' in a restricted hash
195 (F) The failing code has attempted to get or set a key which is not in
196 the current set of allowed keys of a restricted hash.
198 =item Attempt to bless into a reference
200 (F) The CLASSNAME argument to the bless() operator is expected to be
201 the name of the package to bless the resulting object into. You've
202 supplied instead a reference to something: perhaps you wrote
208 bless $self, ref($proto) || $proto;
210 If you actually want to bless into the stringified version
211 of the reference supplied, you need to stringify it yourself, for
214 bless $self, "$proto";
216 =item Attempt to delete disallowed key '%s' from a restricted hash
218 (F) The failing code attempted to delete from a restricted hash a key
219 which is not in its key set.
221 =item Attempt to delete readonly key '%s' from a restricted hash
223 (F) The failing code attempted to delete a key whose value has been
224 declared readonly from a restricted hash.
226 =item Attempt to free non-arena SV: 0x%lx
228 (P internal) All SV objects are supposed to be allocated from arenas
229 that will be garbage collected on exit. An SV was discovered to be
230 outside any of those arenas.
232 =item Attempt to free nonexistent shared string
234 (P internal) Perl maintains a reference counted internal table of
235 strings to optimize the storage and access of hash keys and other
236 strings. This indicates someone tried to decrement the reference count
237 of a string that can no longer be found in the table.
239 =item Attempt to free temp prematurely
241 (W debugging) Mortalized values are supposed to be freed by the
242 free_tmps() routine. This indicates that something else is freeing the
243 SV before the free_tmps() routine gets a chance, which means that the
244 free_tmps() routine will be freeing an unreferenced scalar when it does
247 =item Attempt to free unreferenced glob pointers
249 (P internal) The reference counts got screwed up on symbol aliases.
251 =item Attempt to free unreferenced scalar
253 (W internal) Perl went to decrement the reference count of a scalar to
254 see if it would go to 0, and discovered that it had already gone to 0
255 earlier, and should have been freed, and in fact, probably was freed.
256 This could indicate that SvREFCNT_dec() was called too many times, or
257 that SvREFCNT_inc() was called too few times, or that the SV was
258 mortalized when it shouldn't have been, or that memory has been
261 =item Attempt to join self
263 (F) You tried to join a thread from within itself, which is an
264 impossible task. You may be joining the wrong thread, or you may need
265 to move the join() to some other thread.
267 =item Attempt to pack pointer to temporary value
269 (W pack) You tried to pass a temporary value (like the result of a
270 function, or a computed expression) to the "p" pack() template. This
271 means the result contains a pointer to a location that could become
272 invalid anytime, even before the end of the current statement. Use
273 literals or global values as arguments to the "p" pack() template to
276 =item Attempt to use reference as lvalue in substr
278 (W substr) You supplied a reference as the first argument to substr()
279 used as an lvalue, which is pretty strange. Perhaps you forgot to
280 dereference it first. See L<perlfunc/substr>.
282 =item Bad arg length for %s, is %d, should be %s
284 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
285 or shmctl(). In C parlance, the correct sizes are, respectively,
286 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
287 S<sizeof(struct shmid_ds *)>.
289 =item Bad evalled substitution pattern
291 (F) You've used the C</e> switch to evaluate the replacement for a
292 substitution, but perl found a syntax error in the code to evaluate,
293 most likely an unexpected right brace '}'.
295 =item Bad filehandle: %s
297 (F) A symbol was passed to something wanting a filehandle, but the
298 symbol has no filehandle associated with it. Perhaps you didn't do an
299 open(), or did it in another package.
301 =item Bad free() ignored
303 (S malloc) An internal routine called free() on something that had never
304 been malloc()ed in the first place. Mandatory, but can be disabled by
305 setting environment variable C<PERL_BADFREE> to 0.
307 This message can be seen quite often with DB_File on systems with "hard"
308 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
309 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
313 (P) One of the internal hash routines was passed a null HV pointer.
315 =item Badly placed ()'s
317 (A) You've accidentally run your script through B<csh> instead
318 of Perl. Check the #! line, or manually feed your script into
321 =item Bad name after %s::
323 (F) You started to name a symbol by using a package prefix, and then
324 didn't finish the symbol. In particular, you can't interpolate outside
333 $sym = "mypack::$var";
335 =item Bad realloc() ignored
337 (S malloc) An internal routine called realloc() on something that had
338 never been malloc()ed in the first place. Mandatory, but can be disabled
339 by setting environment variable C<PERL_BADFREE> to 1.
341 =item Bad symbol for array
343 (P) An internal request asked to add an array entry to something that
344 wasn't a symbol table entry.
346 =item Bad symbol for filehandle
348 (P) An internal request asked to add a filehandle entry to something
349 that wasn't a symbol table entry.
351 =item Bad symbol for hash
353 (P) An internal request asked to add a hash entry to something that
354 wasn't a symbol table entry.
356 =item Bareword found in conditional
358 (W bareword) The compiler found a bareword where it expected a
359 conditional, which often indicates that an || or && was parsed as part
360 of the last argument of the previous construct, for example:
364 It may also indicate a misspelled constant that has been interpreted as
367 use constant TYPO => 1;
368 if (TYOP) { print "foo" }
370 The C<strict> pragma is useful in avoiding such errors.
372 =item Bareword "%s" not allowed while "strict subs" in use
374 (F) With "strict subs" in use, a bareword is only allowed as a
375 subroutine identifier, in curly brackets or to the left of the "=>"
376 symbol. Perhaps you need to predeclare a subroutine?
378 =item Bareword "%s" refers to nonexistent package
380 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
381 compiler saw no other uses of that namespace before that point. Perhaps
382 you need to predeclare a package?
384 =item BEGIN failed--compilation aborted
386 (F) An untrapped exception was raised while executing a BEGIN
387 subroutine. Compilation stops immediately and the interpreter is
390 =item BEGIN not safe after errors--compilation aborted
392 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
393 implies a C<BEGIN {}>) after one or more compilation errors had already
394 occurred. Since the intended environment for the C<BEGIN {}> could not
395 be guaranteed (due to the errors), and since subsequent code likely
396 depends on its correct operation, Perl just gave up.
398 =item \1 better written as $1
400 (W syntax) Outside of patterns, backreferences live on as variables.
401 The use of backslashes is grandfathered on the right-hand side of a
402 substitution, but stylistically it's better to use the variable form
403 because other Perl programmers will expect it, and it works better if
404 there are more than 9 backreferences.
406 =item Binary number > 0b11111111111111111111111111111111 non-portable
408 (W portable) The binary number you specified is larger than 2**32-1
409 (4294967295) and therefore non-portable between systems. See
410 L<perlport> for more on portability concerns.
412 =item bind() on closed socket %s
414 (W closed) You tried to do a bind on a closed socket. Did you forget to
415 check the return value of your socket() call? See L<perlfunc/bind>.
417 =item binmode() on closed filehandle %s
419 (W unopened) You tried binmode() on a filehandle that was never opened.
420 Check you control flow and number of arguments.
422 =item Bit vector size > 32 non-portable
424 (W portable) Using bit vector sizes larger than 32 is non-portable.
426 =item Bizarre copy of %s in %s
428 (P) Perl detected an attempt to copy an internal value that is not
431 =item Buffer overflow in prime_env_iter: %s
433 (W internal) A warning peculiar to VMS. While Perl was preparing to
434 iterate over %ENV, it encountered a logical name or symbol definition
435 which was too long, so it was truncated to the string shown.
437 =item Callback called exit
439 (F) A subroutine invoked from an external package via call_sv()
440 exited by calling exit.
442 =item %s() called too early to check prototype
444 (W prototype) You've called a function that has a prototype before the
445 parser saw a definition or declaration for it, and Perl could not check
446 that the call conforms to the prototype. You need to either add an
447 early prototype declaration for the subroutine in question, or move the
448 subroutine definition ahead of the call to get proper prototype
449 checking. Alternatively, if you are certain that you're calling the
450 function correctly, you may put an ampersand before the name to avoid
451 the warning. See L<perlsub>.
453 =item Cannot compress integer in pack
455 (F) An argument to pack("w",...) was too large to compress. The BER
456 compressed integer format can only be used with positive integers, and you
457 attempted to compress Infinity or a very large number (> 1e308).
458 See L<perlfunc/pack>.
460 =item Cannot compress negative numbers in pack
462 (F) An argument to pack("w",...) was negative. The BER compressed integer
463 format can only be used with positive integers. See L<perlfunc/pack>.
465 =item Can only compress unsigned integers in pack
467 (F) An argument to pack("w",...) was not an integer. The BER compressed
468 integer format can only be used with positive integers, and you attempted
469 to compress something else. See L<perlfunc/pack>.
471 =item Can't bless non-reference value
473 (F) Only hard references may be blessed. This is how Perl "enforces"
474 encapsulation of objects. See L<perlobj>.
476 =item Can't call method "%s" in empty package "%s"
478 (F) You called a method correctly, and it correctly indicated a package
479 functioning as a class, but that package doesn't have ANYTHING defined
480 in it, let alone methods. See L<perlobj>.
482 =item Can't call method "%s" on an undefined value
484 (F) You used the syntax of a method call, but the slot filled by the
485 object reference or package name contains an undefined value. Something
486 like this will reproduce the error:
489 process $BADREF 1,2,3;
490 $BADREF->process(1,2,3);
492 =item Can't call method "%s" on unblessed reference
494 (F) A method call must know in what package it's supposed to run. It
495 ordinarily finds this out from the object reference you supply, but you
496 didn't supply an object reference in this case. A reference isn't an
497 object reference until it has been blessed. See L<perlobj>.
499 =item Can't call method "%s" without a package or object reference
501 (F) You used the syntax of a method call, but the slot filled by the
502 object reference or package name contains an expression that returns a
503 defined value which is neither an object reference nor a package name.
504 Something like this will reproduce the error:
507 process $BADREF 1,2,3;
508 $BADREF->process(1,2,3);
510 =item Can't chdir to %s
512 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
513 that you can chdir to, possibly because it doesn't exist.
515 =item Can't check filesystem of script "%s" for nosuid
517 (P) For some reason you can't check the filesystem of the script for
520 =item Can't coerce array into hash
522 (F) You used an array where a hash was expected, but the array has no
523 information on how to map from keys to array indices. You can do that
524 only with arrays that have a hash reference at index 0.
526 =item Can't coerce %s to integer in %s
528 (F) Certain types of SVs, in particular real symbol table entries
529 (typeglobs), can't be forced to stop being what they are. So you can't
539 but then $foo no longer contains a glob.
541 =item Can't coerce %s to number in %s
543 (F) Certain types of SVs, in particular real symbol table entries
544 (typeglobs), can't be forced to stop being what they are.
546 =item Can't coerce %s to string in %s
548 (F) Certain types of SVs, in particular real symbol table entries
549 (typeglobs), can't be forced to stop being what they are.
551 =item Can't create pipe mailbox
553 (P) An error peculiar to VMS. The process is suffering from exhausted
554 quotas or other plumbing problems.
556 =item Can't declare class for non-scalar %s in "%s"
558 (F) Currently, only scalar variables can be declared with a specific
559 class qualifier in a "my" or "our" declaration. The semantics may be
560 extended for other types of variables in future.
562 =item Can't declare %s in "%s"
564 (F) Only scalar, array, and hash variables may be declared as "my" or
565 "our" variables. They must have ordinary identifiers as names.
567 =item Can't do inplace edit: %s is not a regular file
569 (S inplace) You tried to use the B<-i> switch on a special file, such as
570 a file in /dev, or a FIFO. The file was ignored.
572 =item Can't do inplace edit on %s: %s
574 (S inplace) The creation of the new file failed for the indicated
577 =item Can't do inplace edit without backup
579 (F) You're on a system such as MS-DOS that gets confused if you try
580 reading from a deleted (but still opened) file. You have to say
581 C<-i.bak>, or some such.
583 =item Can't do inplace edit: %s would not be unique
585 (S inplace) Your filesystem does not support filenames longer than 14
586 characters and Perl was unable to create a unique filename during
587 inplace editing with the B<-i> switch. The file was ignored.
589 =item Can't do {n,m} with n > m in regex; marked by <-- HERE in m/%s/
591 (F) Minima must be less than or equal to maxima. If you really want your
592 regexp to match something 0 times, just put {0}. The <-- HERE shows in the
593 regular expression about where the problem was discovered. See L<perlre>.
595 =item Can't do setegid!
597 (P) The setegid() call failed for some reason in the setuid emulator of
600 =item Can't do seteuid!
602 (P) The setuid emulator of suidperl failed for some reason.
604 =item Can't do setuid
606 (F) This typically means that ordinary perl tried to exec suidperl to do
607 setuid emulation, but couldn't exec it. It looks for a name of the form
608 sperl5.000 in the same directory that the perl executable resides under
609 the name perl5.000, typically /usr/local/bin on Unix machines. If the
610 file is there, check the execute permissions. If it isn't, ask your
611 sysadmin why he and/or she removed it.
613 =item Can't do waitpid with flags
615 (F) This machine doesn't have either waitpid() or wait4(), so only
616 waitpid() without flags is emulated.
618 =item Can't emulate -%s on #! line
620 (F) The #! line specifies a switch that doesn't make sense at this
621 point. For example, it'd be kind of silly to put a B<-x> on the #!
624 =item Can't exec "%s": %s
626 (W exec) A system(), exec(), or piped open call could not execute the
627 named program for the indicated reason. Typical reasons include: the
628 permissions were wrong on the file, the file wasn't found in
629 C<$ENV{PATH}>, the executable in question was compiled for another
630 architecture, or the #! line in a script points to an interpreter that
631 can't be run for similar reasons. (Or maybe your system doesn't support
636 (F) Perl was trying to execute the indicated program for you because
637 that's what the #! line said. If that's not what you wanted, you may
638 need to mention "perl" on the #! line somewhere.
640 =item Can't execute %s
642 (F) You used the B<-S> switch, but the copies of the script to execute
643 found in the PATH did not have correct permissions.
645 =item Can't find an opnumber for "%s"
647 (F) A string of a form C<CORE::word> was given to prototype(), but there
648 is no builtin with the name C<word>.
650 =item Can't find %s character property "%s"
652 (F) You used C<\p{}> or C<\P{}> but the character property by that name
653 could not be found. Maybe you misspelled the name of the property
654 (remember that the names of character properties consist only of
655 alphanumeric characters), or maybe you forgot the C<Is> or C<In> prefix?
657 =item Can't find label %s
659 (F) You said to goto a label that isn't mentioned anywhere that it's
660 possible for us to go to. See L<perlfunc/goto>.
662 =item Can't find %s on PATH
664 (F) You used the B<-S> switch, but the script to execute could not be
667 =item Can't find %s on PATH, '.' not in PATH
669 (F) You used the B<-S> switch, but the script to execute could not be
670 found in the PATH, or at least not with the correct permissions. The
671 script exists in the current directory, but PATH prohibits running it.
673 =item Can't find %s property definition %s
675 (F) You may have tried to use C<\p> which means a Unicode property (for
676 example C<\p{Lu}> is all uppercase letters). If you did mean to use a
677 Unicode property, see L<perlunicode> for the list of known properties.
678 If you didn't mean to use a Unicode property, escape the C<\p>, either
679 by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, until
682 =item Can't find string terminator %s anywhere before EOF
684 (F) Perl strings can stretch over multiple lines. This message means
685 that the closing delimiter was omitted. Because bracketed quotes count
686 nesting levels, the following is missing its final parenthesis:
688 print q(The character '(' starts a side comment.);
690 If you're getting this error from a here-document, you may have included
691 unseen whitespace before or after your closing tag. A good programmer's
692 editor will have a way to help you find these characters.
696 (F) A fatal error occurred while trying to fork while opening a
699 =item Can't get filespec - stale stat buffer?
701 (S) A warning peculiar to VMS. This arises because of the difference
702 between access checks under VMS and under the Unix model Perl assumes.
703 Under VMS, access checks are done by filename, rather than by bits in
704 the stat buffer, so that ACLs and other protections can be taken into
705 account. Unfortunately, Perl assumes that the stat buffer contains all
706 the necessary information, and passes it, instead of the filespec, to
707 the access checking routine. It will try to retrieve the filespec using
708 the device name and FID present in the stat buffer, but this works only
709 if you haven't made a subsequent call to the CRTL stat() routine,
710 because the device name is overwritten with each call. If this warning
711 appears, the name lookup failed, and the access checking routine gave up
712 and returned FALSE, just to be conservative. (Note: The access checking
713 routine knows about the Perl C<stat> operator and file tests, so you
714 shouldn't ever see this warning in response to a Perl command; it arises
715 only if some internal code takes stat buffers lightly.)
717 =item Can't get pipe mailbox device name
719 (P) An error peculiar to VMS. After creating a mailbox to act as a
720 pipe, Perl can't retrieve its name for later use.
722 =item Can't get SYSGEN parameter value for MAXBUF
724 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
725 mailbox buffers to be, and didn't get an answer.
727 =item Can't "goto" into the middle of a foreach loop
729 (F) A "goto" statement was executed to jump into the middle of a foreach
730 loop. You can't get there from here. See L<perlfunc/goto>.
732 =item Can't "goto" out of a pseudo block
734 (F) A "goto" statement was executed to jump out of what might look like
735 a block, except that it isn't a proper block. This usually occurs if
736 you tried to jump out of a sort() block or subroutine, which is a no-no.
737 See L<perlfunc/goto>.
739 =item Can't goto subroutine from an eval-string
741 (F) The "goto subroutine" call can't be used to jump out of an eval
742 "string". (You can use it to jump out of an eval {BLOCK}, but you
743 probably don't want to.)
745 =item Can't goto subroutine outside a subroutine
747 (F) The deeply magical "goto subroutine" call can only replace one
748 subroutine call for another. It can't manufacture one out of whole
749 cloth. In general you should be calling it out of only an AUTOLOAD
750 routine anyway. See L<perlfunc/goto>.
752 =item Can't ignore signal CHLD, forcing to default
754 (W signal) Perl has detected that it is being run with the SIGCHLD
755 signal (sometimes known as SIGCLD) disabled. Since disabling this
756 signal will interfere with proper determination of exit status of child
757 processes, Perl has reset the signal to its default value. This
758 situation typically indicates that the parent program under which Perl
759 may be running (e.g. cron) is being very careless.
761 =item Can't "last" outside a loop block
763 (F) A "last" statement was executed to break out of the current block,
764 except that there's this itty bitty problem called there isn't a current
765 block. Note that an "if" or "else" block doesn't count as a "loopish"
766 block, as doesn't a block given to sort(), map() or grep(). You can
767 usually double the curlies to get the same effect though, because the
768 inner curlies will be considered a block that loops once. See
771 =item Can't localize lexical variable %s
773 (F) You used local on a variable name that was previously declared as a
774 lexical variable using "my". This is not allowed. If you want to
775 localize a package variable of the same name, qualify it with the
778 =item Can't localize through a reference
780 (F) You said something like C<local $$ref>, which Perl can't currently
781 handle, because when it goes to restore the old value of whatever $ref
782 pointed to after the scope of the local() is finished, it can't be sure
783 that $ref will still be a reference.
785 =item Can't locate %s
787 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be
788 found. Perl looks for the file in all the locations mentioned in @INC,
789 unless the file name included the full path to the file. Perhaps you
790 need to set the PERL5LIB or PERL5OPT environment variable to say where
791 the extra library is, or maybe the script needs to add the library name
792 to @INC. Or maybe you just misspelled the name of the file. See
793 L<perlfunc/require> and L<lib>.
795 =item Can't locate auto/%s.al in @INC
797 (F) A function (or method) was called in a package which allows
798 autoload, but there is no function to autoload. Most probable causes
799 are a misprint in a function/method name or a failure to C<AutoSplit>
800 the file, say, by doing C<make install>.
802 =item Can't locate object method "%s" via package "%s"
804 (F) You called a method correctly, and it correctly indicated a package
805 functioning as a class, but that package doesn't define that particular
806 method, nor does any of its base classes. See L<perlobj>.
808 =item Can't locate package %s for @%s::ISA
810 (W syntax) The @ISA array contained the name of another package that
811 doesn't seem to exist.
813 =item Can't locate PerlIO%s
815 (F) You tried to use in open() a PerlIO layer that does not exist,
816 e.g. open(FH, ">:nosuchlayer", "somefile").
818 =item Can't make list assignment to \%ENV on this system
820 (F) List assignment to %ENV is not supported on some systems, notably
823 =item Can't modify %s in %s
825 (F) You aren't allowed to assign to the item indicated, or otherwise try
826 to change it, such as with an auto-increment.
828 =item Can't modify nonexistent substring
830 (P) The internal routine that does assignment to a substr() was handed
833 =item Can't modify non-lvalue subroutine call
835 (F) Subroutines meant to be used in lvalue context should be declared as
836 such, see L<perlsub/"Lvalue subroutines">.
838 =item Can't msgrcv to read-only var
840 (F) The target of a msgrcv must be modifiable to be used as a receive
843 =item Can't "next" outside a loop block
845 (F) A "next" statement was executed to reiterate the current block, but
846 there isn't a current block. Note that an "if" or "else" block doesn't
847 count as a "loopish" block, as doesn't a block given to sort(), map() or
848 grep(). You can usually double the curlies to get the same effect
849 though, because the inner curlies will be considered a block that loops
850 once. See L<perlfunc/next>.
852 =item Can't open %s: %s
854 (S inplace) The implicit opening of a file through use of the C<< <> >>
855 filehandle, either implicitly under the C<-n> or C<-p> command-line
856 switches, or explicitly, failed for the indicated reason. Usually this
857 is because you don't have read permission for a file which you named on
860 =item Can't open a reference
862 (W io) You tried to open a scalar reference for reading or writing,
863 using the 3-arg open() syntax :
867 but your version of perl is compiled without perlio, and this form of
868 open is not supported.
870 =item Can't open bidirectional pipe
872 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
873 You can try any of several modules in the Perl library to do this, such
874 as IPC::Open2. Alternately, direct the pipe's output to a file using
875 ">", and then read it in under a different file handle.
877 =item Can't open error file %s as stderr
879 (F) An error peculiar to VMS. Perl does its own command line
880 redirection, and couldn't open the file specified after '2>' or '2>>' on
881 the command line for writing.
883 =item Can't open input file %s as stdin
885 (F) An error peculiar to VMS. Perl does its own command line
886 redirection, and couldn't open the file specified after '<' on the
887 command line for reading.
889 =item Can't open output file %s as stdout
891 (F) An error peculiar to VMS. Perl does its own command line
892 redirection, and couldn't open the file specified after '>' or '>>' on
893 the command line for writing.
895 =item Can't open output pipe (name: %s)
897 (P) An error peculiar to VMS. Perl does its own command line
898 redirection, and couldn't open the pipe into which to send data destined
901 =item Can't open perl script%s: %s
903 (F) The script you specified can't be opened for the indicated reason.
905 =item Can't provide tied hash usage; use keys(%hash) to test if empty
907 (F) When a hash is evaluated in scalar context, bucket usage is
908 returned if the hash is populated, and false is returned if the hash
909 is empty. Bucket usage is not currently available for tied hashes.
910 To test if a hash is empty or populated, use keys(%hash) in scalar
913 =item Can't read CRTL environ
915 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
916 from the CRTL's internal environment array and discovered the array was
917 missing. You need to figure out where your CRTL misplaced its environ
918 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
921 =item Can't redefine active sort subroutine %s
923 (F) Perl optimizes the internal handling of sort subroutines and keeps
924 pointers into them. You tried to redefine one such sort subroutine when
925 it was currently active, which is not allowed. If you really want to do
926 this, you should write C<sort { &func } @x> instead of C<sort func @x>.
928 =item Can't "redo" outside a loop block
930 (F) A "redo" statement was executed to restart the current block, but
931 there isn't a current block. Note that an "if" or "else" block doesn't
932 count as a "loopish" block, as doesn't a block given to sort(), map()
933 or grep(). You can usually double the curlies to get the same effect
934 though, because the inner curlies will be considered a block that
935 loops once. See L<perlfunc/redo>.
937 =item Can't remove %s: %s, skipping file
939 (S inplace) You requested an inplace edit without creating a backup
940 file. Perl was unable to remove the original file to replace it with
941 the modified file. The file was left unmodified.
943 =item Can't rename %s to %s: %s, skipping file
945 (S inplace) The rename done by the B<-i> switch failed for some reason,
946 probably because you don't have write permission to the directory.
948 =item Can't reopen input pipe (name: %s) in binary mode
950 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
951 to reopen it to accept binary data. Alas, it failed.
953 =item Can't resolve method `%s' overloading `%s' in package `%s'
955 (F|P) Error resolving overloading specified by a method name (as opposed
956 to a subroutine reference): no such method callable via the package. If
957 method name is C<???>, this is an internal error.
959 =item Can't reswap uid and euid
961 (P) The setreuid() call failed for some reason in the setuid emulator of
964 =item Can't return %s from lvalue subroutine
966 (F) Perl detected an attempt to return illegal lvalues (such as
967 temporary or readonly values) from a subroutine used as an lvalue. This
970 =item Can't return outside a subroutine
972 (F) The return statement was executed in mainline code, that is, where
973 there was no subroutine call to return out of. See L<perlsub>.
975 =item Can't return %s to lvalue scalar context
977 (F) You tried to return a complete array or hash from an lvalue subroutine,
978 but you called the subroutine in a way that made Perl think you meant
979 to return only one value. You probably meant to write parentheses around
980 the call to the subroutine, which tell Perl that the call should be in
983 =item Can't stat script "%s"
985 (P) For some reason you can't fstat() the script even though you have it
986 open already. Bizarre.
988 =item Can't swap uid and euid
990 (P) The setreuid() call failed for some reason in the setuid emulator of
993 =item Can't take log of %g
995 (F) For ordinary real numbers, you can't take the logarithm of a
996 negative number or zero. There's a Math::Complex package that comes
997 standard with Perl, though, if you really want to do that for the
1000 =item Can't take sqrt of %g
1002 (F) For ordinary real numbers, you can't take the square root of a
1003 negative number. There's a Math::Complex package that comes standard
1004 with Perl, though, if you really want to do that.
1006 =item Can't undef active subroutine
1008 (F) You can't undefine a routine that's currently running. You can,
1009 however, redefine it while it's running, and you can even undef the
1010 redefined subroutine while the old routine is running. Go figure.
1014 (F) You tried to unshift an "unreal" array that can't be unshifted, such
1015 as the main Perl stack.
1017 =item Can't upgrade that kind of scalar
1019 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1020 into a more specialized kind of SV. The top several SV types are so
1021 specialized, however, that they cannot be interconverted. This message
1022 indicates that such a conversion was attempted.
1024 =item Can't upgrade to undef
1026 (P) The undefined SV is the bottom of the totem pole, in the scheme of
1027 upgradability. Upgrading to undef indicates an error in the code
1030 =item Can't use anonymous symbol table for method lookup
1032 (F) The internal routine that does method lookup was handed a symbol
1033 table that doesn't have a name. Symbol tables can become anonymous
1034 for example by undefining stashes: C<undef %Some::Package::>.
1036 =item Can't use an undefined value as %s reference
1038 (F) A value used as either a hard reference or a symbolic reference must
1039 be a defined value. This helps to delurk some insidious errors.
1041 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1043 (F) Only hard references are allowed by "strict refs". Symbolic
1044 references are disallowed. See L<perlref>.
1046 =item Can't use %! because Errno.pm is not available
1048 (F) The first time the %! hash is used, perl automatically loads the
1049 Errno.pm module. The Errno module is expected to tie the %! hash to
1050 provide symbolic names for C<$!> errno values.
1052 =item Can't use %s for loop variable
1054 (F) Only a simple scalar variable may be used as a loop variable on a
1057 =item Can't use global %s in "my"
1059 (F) You tried to declare a magical variable as a lexical variable. This
1060 is not allowed, because the magic can be tied to only one location
1061 (namely the global variable) and it would be incredibly confusing to
1062 have variables in your program that looked like magical variables but
1065 =item Can't use "my %s" in sort comparison
1067 (F) The global variables $a and $b are reserved for sort comparisons.
1068 You mentioned $a or $b in the same line as the <=> or cmp operator,
1069 and the variable had earlier been declared as a lexical variable.
1070 Either qualify the sort variable with the package name, or rename the
1073 =item Can't use %s ref as %s ref
1075 (F) You've mixed up your reference types. You have to dereference a
1076 reference of the type needed. You can use the ref() function to
1077 test the type of the reference, if need be.
1079 =item Can't use string ("%s") as %s ref while "strict refs" in use
1081 (F) Only hard references are allowed by "strict refs". Symbolic
1082 references are disallowed. See L<perlref>.
1084 =item Can't use subscript on %s
1086 (F) The compiler tried to interpret a bracketed expression as a
1087 subscript. But to the left of the brackets was an expression that
1088 didn't look like an array reference, or anything else subscriptable.
1090 =item Can't use \%c to mean $%c in expression
1092 (W syntax) In an ordinary expression, backslash is a unary operator that
1093 creates a reference to its argument. The use of backslash to indicate a
1094 backreference to a matched substring is valid only as part of a regular
1095 expression pattern. Trying to do this in ordinary Perl code produces a
1096 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1099 =item Can't weaken a nonreference
1101 (F) You attempted to weaken something that was not a reference. Only
1102 references can be weakened.
1104 =item Can't x= to read-only value
1106 (F) You tried to repeat a constant value (often the undefined value)
1107 with an assignment operator, which implies modifying the value itself.
1108 Perhaps you need to copy the value to a temporary, and repeat that.
1110 =item Character in "C" format wrapped in pack
1116 where $x is either less than 0 or more than 255; the C<"C"> format is
1117 only for encoding native operating system characters (ASCII, EBCDIC,
1118 and so on) and not for Unicode characters, so Perl behaved as if you meant
1122 If you actually want to pack Unicode codepoints, use the C<"U"> format
1125 =item Character in "c" format wrapped in pack
1131 where $x is either less than -128 or more than 127; the C<"c"> format
1132 is only for encoding native operating system characters (ASCII, EBCDIC,
1133 and so on) and not for Unicode characters, so Perl behaved as if you meant
1135 pack("c", $x & 255);
1137 If you actually want to pack Unicode codepoints, use the C<"U"> format
1140 =item close() on unopened filehandle %s
1142 (W unopened) You tried to close a filehandle that was never opened.
1144 =item Code missing after '/'
1146 (F) You had a (sub-)template that ends with a '/'. There must be another
1147 template code following the slash. See L<perlfunc/pack>.
1149 =item %s: Command not found
1151 (A) You've accidentally run your script through B<csh> instead of Perl.
1152 Check the #! line, or manually feed your script into Perl yourself.
1154 =item Compilation failed in require
1156 (F) Perl could not compile a file specified in a C<require> statement.
1157 Perl uses this generic message when none of the errors that it
1158 encountered were severe enough to halt compilation immediately.
1160 =item Complex regular subexpression recursion limit (%d) exceeded
1162 (W regexp) The regular expression engine uses recursion in complex
1163 situations where back-tracking is required. Recursion depth is limited
1164 to 32766, or perhaps less in architectures where the stack cannot grow
1165 arbitrarily. ("Simple" and "medium" situations are handled without
1166 recursion and are not subject to a limit.) Try shortening the string
1167 under examination; looping in Perl code (e.g. with C<while>) rather than
1168 in the regular expression engine; or rewriting the regular expression so
1169 that it is simpler or backtracks less. (See L<perlfaq2> for information
1170 on I<Mastering Regular Expressions>.)
1172 =item cond_broadcast() called on unlocked variable
1174 (W threads) Within a thread-enabled program, you tried to call
1175 cond_broadcast() on a variable which wasn't locked. The cond_broadcast()
1176 function is used to wake up another thread that is waiting in a
1177 cond_wait(). To ensure that the signal isn't sent before the other thread
1178 has a chance to enter the wait, it is usual for the signaling thread to
1179 first wait for a lock on variable. This lock attempt will only succeed
1180 after the other thread has entered cond_wait() and thus relinquished the
1183 =item cond_signal() called on unlocked variable
1185 (W threads) Within a thread-enabled program, you tried to call
1186 cond_signal() on a variable which wasn't locked. The cond_signal()
1187 function is used to wake up another thread that is waiting in a
1188 cond_wait(). To ensure that the signal isn't sent before the other thread
1189 has a chance to enter the wait, it is usual for the signaling thread to
1190 first wait for a lock on variable. This lock attempt will only succeed
1191 after the other thread has entered cond_wait() and thus relinquished the
1194 =item connect() on closed socket %s
1196 (W closed) You tried to do a connect on a closed socket. Did you forget
1197 to check the return value of your socket() call? See
1198 L<perlfunc/connect>.
1200 =item Constant(%s)%s: %s
1202 (F) The parser found inconsistencies either while attempting to define
1203 an overloaded constant, or when trying to find the character name
1204 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1205 corresponding C<overload> or C<charnames> pragma? See L<charnames> and
1208 =item Constant is not %s reference
1210 (F) A constant value (perhaps declared using the C<use constant> pragma)
1211 is being dereferenced, but it amounts to the wrong type of reference.
1212 The message indicates the type of reference that was expected. This
1213 usually indicates a syntax error in dereferencing the constant value.
1214 See L<perlsub/"Constant Functions"> and L<constant>.
1216 =item Constant subroutine %s redefined
1218 (S) You redefined a subroutine which had previously been
1219 eligible for inlining. See L<perlsub/"Constant Functions"> for
1220 commentary and workarounds.
1222 =item Constant subroutine %s undefined
1224 (W misc) You undefined a subroutine which had previously been eligible
1225 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1228 =item Copy method did not return a reference
1230 (F) The method which overloads "=" is buggy. See
1231 L<overload/Copy Constructor>.
1233 =item CORE::%s is not a keyword
1235 (F) The CORE:: namespace is reserved for Perl keywords.
1237 =item corrupted regexp pointers
1239 (P) The regular expression engine got confused by what the regular
1240 expression compiler gave it.
1242 =item corrupted regexp program
1244 (P) The regular expression engine got passed a regexp program without a
1247 =item Corrupt malloc ptr 0x%lx at 0x%lx
1249 (P) The malloc package that comes with Perl had an internal failure.
1251 =item Count after length/code in unpack
1253 (F) You had an unpack template indicating a counted-length string, but
1254 you have also specified an explicit size for the string. See
1257 =item Deep recursion on subroutine "%s"
1259 (W recursion) This subroutine has called itself (directly or indirectly)
1260 100 times more than it has returned. This probably indicates an
1261 infinite recursion, unless you're writing strange benchmark programs, in
1262 which case it indicates something else.
1264 =item defined(@array) is deprecated
1266 (D deprecated) defined() is not usually useful on arrays because it
1267 checks for an undefined I<scalar> value. If you want to see if the
1268 array is empty, just use C<if (@array) { # not empty }> for example.
1270 =item defined(%hash) is deprecated
1272 (D deprecated) defined() is not usually useful on hashes because it
1273 checks for an undefined I<scalar> value. If you want to see if the hash
1274 is empty, just use C<if (%hash) { # not empty }> for example.
1276 =item %s defines neither package nor VERSION--version check failed
1278 (F) You said something like "use Module 42" but in the Module file
1279 there are neither package declarations nor a C<$VERSION>.
1281 =item Delimiter for here document is too long
1283 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1284 long for Perl to handle. You have to be seriously twisted to write code
1285 that triggers this error.
1287 =item Did not produce a valid header
1291 =item %s did not return a true value
1293 (F) A required (or used) file must return a true value to indicate that
1294 it compiled correctly and ran its initialization code correctly. It's
1295 traditional to end such a file with a "1;", though any true value would
1296 do. See L<perlfunc/require>.
1298 =item (Did you mean &%s instead?)
1300 (W) You probably referred to an imported subroutine &FOO as $FOO or some
1303 =item (Did you mean "local" instead of "our"?)
1305 (W misc) Remember that "our" does not localize the declared global
1306 variable. You have declared it again in the same lexical scope, which
1309 =item (Did you mean $ or @ instead of %?)
1311 (W) You probably said %hash{$key} when you meant $hash{$key} or
1312 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1317 (F) You passed die() an empty string (the equivalent of C<die "">) or
1318 you called it with no args and both C<$@> and C<$_> were empty.
1320 =item Document contains no data
1324 =item %s does not define %s::VERSION--version check failed
1326 (F) You said something like "use Module 42" but the Module did not
1327 define a C<$VERSION.>
1329 =item '/' does not take a repeat count
1331 (F) You cannot put a repeat count of any kind right after the '/' code.
1332 See L<perlfunc/pack>.
1334 =item Don't know how to handle magic of type '%s'
1336 (P) The internal handling of magical variables has been cursed.
1338 =item do_study: out of memory
1340 (P) This should have been caught by safemalloc() instead.
1342 =item (Do you need to predeclare %s?)
1344 (S) This is an educated guess made in conjunction with the message "%s
1345 found where operator expected". It often means a subroutine or module
1346 name is being referenced that hasn't been declared yet. This may be
1347 because of ordering problems in your file, or because of a missing
1348 "sub", "package", "require", or "use" statement. If you're referencing
1349 something that isn't defined yet, you don't actually have to define the
1350 subroutine or package before the current location. You can use an empty
1351 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1353 =item dump() better written as CORE::dump()
1355 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1356 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1358 =item Duplicate free() ignored
1360 (S malloc) An internal routine called free() on something that had
1363 =item elseif should be elsif
1365 (S) There is no keyword "elseif" in Perl because Larry thinks it's ugly.
1366 Your code will be interpreted as an attempt to call a method named
1367 "elseif" for the class returned by the following block. This is
1368 unlikely to be what you want.
1372 (F) C<\p> and C<\P> are used to introduce a named Unicode property, as
1373 described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
1374 a regular expression without specifying the property name.
1376 =item entering effective %s failed
1378 (F) While under the C<use filetest> pragma, switching the real and
1379 effective uids or gids failed.
1381 =item Error converting file specification %s
1383 (F) An error peculiar to VMS. Because Perl may have to deal with file
1384 specifications in either VMS or Unix syntax, it converts them to a
1385 single form when it must operate on them directly. Either you've passed
1386 an invalid file specification to Perl, or you've found a case the
1387 conversion routines don't handle. Drat.
1389 =item %s: Eval-group in insecure regular expression
1391 (F) Perl detected tainted data when trying to compile a regular
1392 expression that contains the C<(?{ ... })> zero-width assertion, which
1393 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1395 =item %s: Eval-group not allowed at run time
1397 (F) Perl tried to compile a regular expression containing the
1398 C<(?{ ... })> zero-width assertion at run time, as it would when the
1399 pattern contains interpolated values. Since that is a security risk, it
1400 is not allowed. If you insist, you may still do this by explicitly
1401 building the pattern from an interpolated string at run time and using
1402 that in an eval(). See L<perlre/(?{ code })>.
1404 =item %s: Eval-group not allowed, use re 'eval'
1406 (F) A regular expression contained the C<(?{ ... })> zero-width
1407 assertion, but that construct is only allowed when the C<use re 'eval'>
1408 pragma is in effect. See L<perlre/(?{ code })>.
1410 =item Excessively long <> operator
1412 (F) The contents of a <> operator may not exceed the maximum size of a
1413 Perl identifier. If you're just trying to glob a long list of
1414 filenames, try using the glob() operator, or put the filenames into a
1415 variable and glob that.
1417 =item exec? I'm not *that* kind of operating system
1419 (F) The C<exec> function is not implemented in MacPerl. See L<perlport>.
1421 =item Execution of %s aborted due to compilation errors
1423 (F) The final summary message when a Perl compilation fails.
1425 =item Exiting eval via %s
1427 (W exiting) You are exiting an eval by unconventional means, such as a
1428 goto, or a loop control statement.
1430 =item Exiting format via %s
1432 (W exiting) You are exiting a format by unconventional means, such as a
1433 goto, or a loop control statement.
1435 =item Exiting pseudo-block via %s
1437 (W exiting) You are exiting a rather special block construct (like a
1438 sort block or subroutine) by unconventional means, such as a goto, or a
1439 loop control statement. See L<perlfunc/sort>.
1441 =item Exiting subroutine via %s
1443 (W exiting) You are exiting a subroutine by unconventional means, such
1444 as a goto, or a loop control statement.
1446 =item Exiting substitution via %s
1448 (W exiting) You are exiting a substitution by unconventional means, such
1449 as a return, a goto, or a loop control statement.
1451 =item Explicit blessing to '' (assuming package main)
1453 (W misc) You are blessing a reference to a zero length string. This has
1454 the effect of blessing the reference into the package main. This is
1455 usually not what you want. Consider providing a default target package,
1456 e.g. bless($ref, $p || 'MyPackage');
1458 =item %s: Expression syntax
1460 (A) You've accidentally run your script through B<csh> instead of Perl.
1461 Check the #! line, or manually feed your script into Perl yourself.
1463 =item %s failed--call queue aborted
1465 (F) An untrapped exception was raised while executing a CHECK, INIT, or
1466 END subroutine. Processing of the remainder of the queue of such
1467 routines has been prematurely ended.
1469 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1471 (W regexp) A character class range must start and end at a literal
1472 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1473 in your false range is interpreted as a literal "-". Consider quoting the
1474 "-", "\-". The <-- HERE shows in the regular expression about where the
1475 problem was discovered. See L<perlre>.
1477 =item Fatal VMS error at %s, line %d
1479 (P) An error peculiar to VMS. Something untoward happened in a VMS
1480 system service or RTL routine; Perl's exit status should provide more
1481 details. The filename in "at %s" and the line number in "line %d" tell
1482 you which section of the Perl source code is distressed.
1484 =item fcntl is not implemented
1486 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1487 PDP-11 or something?
1489 =item Filehandle %s opened only for input
1491 (W io) You tried to write on a read-only filehandle. If you intended
1492 it to be a read-write filehandle, you needed to open it with "+<" or
1493 "+>" or "+>>" instead of with "<" or nothing. If you intended only to
1494 write the file, use ">" or ">>". See L<perlfunc/open>.
1496 =item Filehandle %s opened only for output
1498 (W io) You tried to read from a filehandle opened only for writing, If
1499 you intended it to be a read/write filehandle, you needed to open it
1500 with "+<" or "+>" or "+>>" instead of with "<" or nothing. If you
1501 intended only to read from the file, use "<". See L<perlfunc/open>.
1502 Another possibility is that you attempted to open filedescriptor 0
1503 (also known as STDIN) for output (maybe you closed STDIN earlier?).
1505 =item Filehandle %s reopened as %s only for input
1507 (W io) You opened for reading a filehandle that got the same filehandle id
1508 as STDOUT or STDERR. This occured because you closed STDOUT or STDERR
1511 =item Filehandle STDIN reopened as %s only for output
1513 (W io) You opened for writing a filehandle that got the same filehandle id
1514 as STDIN. This occured because you closed STDIN previously.
1516 =item Final $ should be \$ or $name
1518 (F) You must now decide whether the final $ in a string was meant to be
1519 a literal dollar sign, or was meant to introduce a variable name that
1520 happens to be missing. So you have to put either the backslash or the
1523 =item flock() on closed filehandle %s
1525 (W closed) The filehandle you're attempting to flock() got itself closed
1526 some time before now. Check your control flow. flock() operates on
1527 filehandles. Are you attempting to call flock() on a dirhandle by the
1530 =item Format not terminated
1532 (F) A format must be terminated by a line with a solitary dot. Perl got
1533 to the end of your file without finding such a line.
1535 =item Format %s redefined
1537 (W redefine) You redefined a format. To suppress this warning, say
1540 no warnings 'redefine';
1541 eval "format NAME =...";
1544 =item Found = in conditional, should be ==
1554 (or something like that).
1556 =item %s found where operator expected
1558 (S) The Perl lexer knows whether to expect a term or an operator. If it
1559 sees what it knows to be a term when it was expecting to see an
1560 operator, it gives you this warning. Usually it indicates that an
1561 operator or delimiter was omitted, such as a semicolon.
1563 =item gdbm store returned %d, errno %d, key "%s"
1565 (S) A warning from the GDBM_File extension that a store failed.
1567 =item gethostent not implemented
1569 (F) Your C library apparently doesn't implement gethostent(), probably
1570 because if it did, it'd feel morally obligated to return every hostname
1573 =item get%sname() on closed socket %s
1575 (W closed) You tried to get a socket or peer socket name on a closed
1576 socket. Did you forget to check the return value of your socket() call?
1578 =item getpwnam returned invalid UIC %#o for user "%s"
1580 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1581 C<getpwnam> operator returned an invalid UIC.
1583 =item getsockopt() on closed socket %s
1585 (W closed) You tried to get a socket option on a closed socket. Did you
1586 forget to check the return value of your socket() call? See
1587 L<perlfunc/getsockopt>.
1589 =item Global symbol "%s" requires explicit package name
1591 (F) You've said "use strict vars", which indicates that all variables
1592 must either be lexically scoped (using "my"), declared beforehand using
1593 "our", or explicitly qualified to say which package the global variable
1596 =item glob failed (%s)
1598 (W glob) Something went wrong with the external program(s) used for
1599 C<glob> and C<< <*.c> >>. Usually, this means that you supplied a
1600 C<glob> pattern that caused the external program to fail and exit with a
1601 nonzero status. If the message indicates that the abnormal exit
1602 resulted in a coredump, this may also mean that your csh (C shell) is
1603 broken. If so, you should change all of the csh-related variables in
1604 config.sh: If you have tcsh, make the variables refer to it as if it
1605 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1606 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1607 think csh is missing. In either case, after editing config.sh, run
1608 C<./Configure -S> and rebuild Perl.
1610 =item Glob not terminated
1612 (F) The lexer saw a left angle bracket in a place where it was expecting
1613 a term, so it's looking for the corresponding right angle bracket, and
1614 not finding it. Chances are you left some needed parentheses out
1615 earlier in the line, and you really meant a "less than".
1617 =item Got an error from DosAllocMem
1619 (P) An error peculiar to OS/2. Most probably you're using an obsolete
1620 version of Perl, and this should not happen anyway.
1622 =item goto must have label
1624 (F) Unlike with "next" or "last", you're not allowed to goto an
1625 unspecified destination. See L<perlfunc/goto>.
1627 =item ()-group starts with a count
1629 (F) A ()-group started with a count. A count is
1630 supposed to follow something: a template character or a ()-group.
1631 See L<perlfunc/pack>.
1633 =item %s had compilation errors
1635 (F) The final summary message when a C<perl -c> fails.
1637 =item Had to create %s unexpectedly
1639 (S internal) A routine asked for a symbol from a symbol table that ought
1640 to have existed already, but for some reason it didn't, and had to be
1641 created on an emergency basis to prevent a core dump.
1643 =item $* is no longer supported
1645 (D deprecated) The special variable C<$*>, deprecated in older perls, has
1646 been removed as of 5.9.0 and is no longer supported. You should use the
1647 C<//m> and C<//s> regexp modifiers instead.
1649 =item Hash %%s missing the % in argument %d of %s()
1651 (D deprecated) Really old Perl let you omit the % on hash names in some
1652 spots. This is now heavily deprecated.
1654 =item %s has too many errors
1656 (F) The parser has given up trying to parse the program after 10 errors.
1657 Further error messages would likely be uninformative.
1659 =item Hexadecimal number > 0xffffffff non-portable
1661 (W portable) The hexadecimal number you specified is larger than 2**32-1
1662 (4294967295) and therefore non-portable between systems. See
1663 L<perlport> for more on portability concerns.
1665 =item Identifier too long
1667 (F) Perl limits identifiers (names for variables, functions, etc.) to
1668 about 250 characters for simple names, and somewhat more for compound
1669 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
1670 of Perl are likely to eliminate these arbitrary limitations.
1672 =item Illegal binary digit %s
1674 (F) You used a digit other than 0 or 1 in a binary number.
1676 =item Illegal binary digit %s ignored
1678 (W digit) You may have tried to use a digit other than 0 or 1 in a
1679 binary number. Interpretation of the binary number stopped before the
1682 =item Illegal character %s (carriage return)
1684 (F) Perl normally treats carriage returns in the program text as it
1685 would any other whitespace, which means you should never see this error
1686 when Perl was built using standard options. For some reason, your
1687 version of Perl appears to have been built without this support. Talk
1688 to your Perl administrator.
1690 =item Illegal character in prototype for %s : %s
1692 (W syntax) An illegal character was found in a prototype declaration. Legal
1693 characters in prototypes are $, @, %, *, ;, [, ], &, and \.
1695 =item Illegal declaration of anonymous subroutine
1697 (F) When using the C<sub> keyword to construct an anonymous subroutine,
1698 you must always specify a block of code. See L<perlsub>.
1700 =item Illegal division by zero
1702 (F) You tried to divide a number by 0. Either something was wrong in
1703 your logic, or you need to put a conditional in to guard against
1706 =item Illegal hexadecimal digit %s ignored
1708 (W digit) You may have tried to use a character other than 0 - 9 or
1709 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
1710 number stopped before the illegal character.
1712 =item Illegal modulus zero
1714 (F) You tried to divide a number by 0 to get the remainder. Most
1715 numbers don't take to this kindly.
1717 =item Illegal number of bits in vec
1719 (F) The number of bits in vec() (the third argument) must be a power of
1720 two from 1 to 32 (or 64, if your platform supports that).
1722 =item Illegal octal digit %s
1724 (F) You used an 8 or 9 in an octal number.
1726 =item Illegal octal digit %s ignored
1728 (W digit) You may have tried to use an 8 or 9 in an octal number.
1729 Interpretation of the octal number stopped before the 8 or 9.
1731 =item Illegal switch in PERL5OPT: %s
1733 (X) The PERL5OPT environment variable may only be used to set the
1734 following switches: B<-[DIMUdmtw]>.
1736 =item Ill-formed CRTL environ value "%s"
1738 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
1739 internal environ array, and encountered an element without the C<=>
1740 delimiter used to separate keys from values. The element is ignored.
1742 =item Ill-formed message in prime_env_iter: |%s|
1744 (W internal) A warning peculiar to VMS. Perl tried to read a logical
1745 name or CLI symbol definition when preparing to iterate over %ENV, and
1746 didn't see the expected delimiter between key and value, so the line was
1749 =item Impossible to activate assertion call
1751 (W assertions) You're calling an assertion function in a block that is
1752 not under the control of the C<assertions> pragma.
1754 =item (in cleanup) %s
1756 (W misc) This prefix usually indicates that a DESTROY() method raised
1757 the indicated exception. Since destructors are usually called by the
1758 system at arbitrary points during execution, and often a vast number of
1759 times, the warning is issued only once for any number of failures that
1760 would otherwise result in the same message being repeated.
1762 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
1763 also result in this warning. See L<perlcall/G_KEEPERR>.
1765 =item In EBCDIC the v-string components cannot exceed 2147483647
1767 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
1768 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
1769 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
1771 =item Insecure dependency in %s
1773 (F) You tried to do something that the tainting mechanism didn't like.
1774 The tainting mechanism is turned on when you're running setuid or
1775 setgid, or when you specify B<-T> to turn it on explicitly. The
1776 tainting mechanism labels all data that's derived directly or indirectly
1777 from the user, who is considered to be unworthy of your trust. If any
1778 such data is used in a "dangerous" operation, you get this error. See
1779 L<perlsec> for more information.
1781 =item Insecure directory in %s
1783 (F) You can't use system(), exec(), or a piped open in a setuid or
1784 setgid script if C<$ENV{PATH}> contains a directory that is writable by
1785 the world. See L<perlsec>.
1787 =item Insecure $ENV{%s} while running %s
1789 (F) You can't use system(), exec(), or a piped open in a setuid or
1790 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
1791 C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
1792 supplied (or potentially supplied) by the user. The script must set
1793 the path to a known value, using trustworthy data. See L<perlsec>.
1795 =item Integer overflow in %s number
1797 (W overflow) The hexadecimal, octal or binary number you have specified
1798 either as a literal or as an argument to hex() or oct() is too big for
1799 your architecture, and has been converted to a floating point number.
1800 On a 32-bit architecture the largest hexadecimal, octal or binary number
1801 representable without overflow is 0xFFFFFFFF, 037777777777, or
1802 0b11111111111111111111111111111111 respectively. Note that Perl
1803 transparently promotes all numbers to a floating point representation
1804 internally--subject to loss of precision errors in subsequent
1807 =item Integer overflow in version
1809 (F) Some portion of a version initialization is too large for the
1810 size of integers for your architecture. This is not a warning
1811 because there is no rational reason for a version to try and use a
1812 element larger than typically 2**32. This is usually caused by
1813 trying to use some odd mathematical operation as a version, like
1816 =item Internal disaster in regex; marked by <-- HERE in m/%s/
1818 (P) Something went badly wrong in the regular expression parser.
1819 The <-- HERE shows in the regular expression about where the problem was
1822 =item Internal inconsistency in tracking vforks
1824 (S) A warning peculiar to VMS. Perl keeps track of the number of times
1825 you've called C<fork> and C<exec>, to determine whether the current call
1826 to C<exec> should affect the current script or a subprocess (see
1827 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
1828 Perl is making a guess and treating this C<exec> as a request to
1829 terminate the Perl script and execute the specified command.
1831 =item Internal urp in regex; marked by <-- HERE in m/%s/
1833 (P) Something went badly awry in the regular expression parser. The
1834 <-- HERE shows in the regular expression about where the problem was
1837 =item %s (...) interpreted as function
1839 (W syntax) You've run afoul of the rule that says that any list operator
1840 followed by parentheses turns into a function, with all the list
1841 operators arguments found inside the parentheses. See
1842 L<perlop/Terms and List Operators (Leftward)>.
1844 =item Invalid %s attribute: %s
1846 The indicated attribute for a subroutine or variable was not recognized
1847 by Perl or by a user-supplied handler. See L<attributes>.
1849 =item Invalid %s attributes: %s
1851 The indicated attributes for a subroutine or variable were not
1852 recognized by Perl or by a user-supplied handler. See L<attributes>.
1854 =item Invalid conversion in %s: "%s"
1856 (W printf) Perl does not understand the given format conversion. See
1857 L<perlfunc/sprintf>.
1859 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
1861 (F) The range specified in a character class had a minimum character
1862 greater than the maximum character. One possibility is that you forgot the
1863 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
1864 up to C<ff>. The <-- HERE shows in the regular expression about where the
1865 problem was discovered. See L<perlre>.
1867 =item Invalid range "%s" in transliteration operator
1869 (F) The range specified in the tr/// or y/// operator had a minimum
1870 character greater than the maximum character. See L<perlop>.
1872 =item Invalid separator character %s in attribute list
1874 (F) Something other than a colon or whitespace was seen between the
1875 elements of an attribute list. If the previous attribute had a
1876 parenthesised parameter list, perhaps that list was terminated too soon.
1879 =item Invalid type '%s' in %s
1881 (F) The given character is not a valid pack or unpack type.
1882 See L<perlfunc/pack>.
1883 (W) The given character is not a valid pack or unpack type but used to be
1886 =item Invalid version format (multiple underscores)
1888 (F) Versions may contain at most a single underscore, which signals
1889 that the version is a beta release. See L<version> for the allowed
1892 =item Invalid version format (underscores before decimal)
1894 (F) Versions may not contain decimals after the optional underscore.
1895 See L<version> for the allowed version formats.
1897 =item ioctl is not implemented
1899 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1900 strange for a machine that supports C.
1902 =item ioctl() on unopened %s
1904 (W unopened) You tried ioctl() on a filehandle that was never opened.
1905 Check you control flow and number of arguments.
1907 =item IO::Socket::atmark not implemented on this architecture
1909 (F) Your machine doesn't implement the sockatmark() functionality,
1910 neither as a system call or an ioctl call (SIOCATMARK).
1912 =item `%s' is not a code reference
1914 (W overload) The second (fourth, sixth, ...) argument of overload::constant
1915 needs to be a code reference. Either an anonymous subroutine, or a reference
1918 =item `%s' is not an overloadable type
1920 (W overload) You tried to overload a constant type the overload package is
1923 =item junk on end of regexp
1925 (P) The regular expression parser is confused.
1927 =item Label not found for "last %s"
1929 (F) You named a loop to break out of, but you're not currently in a loop
1930 of that name, not even if you count where you were called from. See
1933 =item Label not found for "next %s"
1935 (F) You named a loop to continue, but you're not currently in a loop of
1936 that name, not even if you count where you were called from. See
1939 =item Label not found for "redo %s"
1941 (F) You named a loop to restart, but you're not currently in a loop of
1942 that name, not even if you count where you were called from. See
1945 =item leaving effective %s failed
1947 (F) While under the C<use filetest> pragma, switching the real and
1948 effective uids or gids failed.
1950 =item length/code after end of string in unpack
1952 (F) While unpacking, the string buffer was alread used up when an unpack
1953 length/code combination tried to obtain more data. This results in
1954 an undefined value for the length. See L<perlfunc/pack>.
1956 =item listen() on closed socket %s
1958 (W closed) You tried to do a listen on a closed socket. Did you forget
1959 to check the return value of your socket() call? See
1962 =item Lookbehind longer than %d not implemented in regex; marked by <-- HERE in m/%s/
1964 (F) There is currently a limit on the length of string which lookbehind can
1965 handle. This restriction may be eased in a future release. The <-- HERE
1966 shows in the regular expression about where the problem was discovered.
1968 =item lstat() on filehandle %s
1970 (W io) You tried to do an lstat on a filehandle. What did you mean
1971 by that? lstat() makes sense only on filenames. (Perl did a fstat()
1972 instead on the filehandle.)
1974 =item Lvalue subs returning %s not implemented yet
1976 (F) Due to limitations in the current implementation, array and hash
1977 values cannot be returned in subroutines used in lvalue context. See
1978 L<perlsub/"Lvalue subroutines">.
1980 =item Malformed integer in [] in pack
1982 (F) Between the brackets enclosing a numeric repeat count only digits
1983 are permitted. See L<perlfunc/pack>.
1985 =item Malformed integer in [] in unpack
1987 (F) Between the brackets enclosing a numeric repeat count only digits
1988 are permitted. See L<perlfunc/pack>.
1990 =item Malformed PERLLIB_PREFIX
1992 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
1999 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2000 a builtin library search path, prefix2 is substituted. The error may
2001 appear if components are not found, or are too long. See
2002 "PERLLIB_PREFIX" in L<perlos2>.
2004 =item Malformed prototype for %s: %s
2006 (F) You tried to use a function with a malformed prototype. The
2007 syntax of function prototypes is given a brief compile-time check for
2008 obvious errors like invalid characters. A more rigorous check is run
2009 when the function is called.
2011 =item Malformed UTF-8 character (%s)
2013 Perl detected something that didn't comply with UTF-8 encoding rules.
2015 One possible cause is that you read in data that you thought to be in
2016 UTF-8 but it wasn't (it was for example legacy 8-bit data). Another
2017 possibility is careless use of utf8::upgrade().
2019 =item Malformed UTF-16 surrogate
2021 Perl thought it was reading UTF-16 encoded character data but while
2022 doing it Perl met a malformed Unicode surrogate.
2024 =item %s matches null string many times in regex; marked by <-- HERE in m/%s/
2026 (W regexp) The pattern you've specified would be an infinite loop if the
2027 regular expression engine didn't specifically check for that. The <-- HERE
2028 shows in the regular expression about where the problem was discovered.
2031 =item "%s" may clash with future reserved word
2033 (W) This warning may be due to running a perl5 script through a perl4
2034 interpreter, especially if the word that is being warned about is
2037 =item % may not be used in pack
2039 (F) You can't pack a string by supplying a checksum, because the
2040 checksumming process loses information, and you can't go the other way.
2041 See L<perlfunc/unpack>.
2043 =item Method for operation %s not found in package %s during blessing
2045 (F) An attempt was made to specify an entry in an overloading table that
2046 doesn't resolve to a valid subroutine. See L<overload>.
2048 =item Method %s not permitted
2052 =item Might be a runaway multi-line %s string starting on line %d
2054 (S) An advisory indicating that the previous error may have been caused
2055 by a missing delimiter on a string or pattern, because it eventually
2056 ended earlier on the current line.
2058 =item Misplaced _ in number
2060 (W syntax) An underscore (underbar) in a numeric constant did not
2061 separate two digits.
2063 =item Missing %sbrace%s on \N{}
2065 (F) Wrong syntax of character name literal C<\N{charname}> within
2066 double-quotish context.
2068 =item Missing comma after first argument to %s function
2070 (F) While certain functions allow you to specify a filehandle or an
2071 "indirect object" before the argument list, this ain't one of them.
2073 =item Missing command in piped open
2075 (W pipe) You used the C<open(FH, "| command")> or
2076 C<open(FH, "command |")> construction, but the command was missing or
2079 =item Missing control char name in \c
2081 (F) A double-quoted string ended with "\c", without the required control
2084 =item Missing name in "my sub"
2086 (F) The reserved syntax for lexically scoped subroutines requires that
2087 they have a name with which they can be found.
2089 =item Missing $ on loop variable
2091 (F) Apparently you've been programming in B<csh> too much. Variables
2092 are always mentioned with the $ in Perl, unlike in the shells, where it
2093 can vary from one line to the next.
2095 =item (Missing operator before %s?)
2097 (S) This is an educated guess made in conjunction with the message "%s
2098 found where operator expected". Often the missing operator is a comma.
2100 =item Missing right brace on %s
2102 (F) Missing right brace in C<\p{...}> or C<\P{...}>.
2104 =item Missing right curly or square bracket
2106 (F) The lexer counted more opening curly or square brackets than closing
2107 ones. As a general rule, you'll find it's missing near the place you
2110 =item (Missing semicolon on previous line?)
2112 (S) This is an educated guess made in conjunction with the message "%s
2113 found where operator expected". Don't automatically put a semicolon on
2114 the previous line just because you saw this message.
2116 =item Modification of a read-only value attempted
2118 (F) You tried, directly or indirectly, to change the value of a
2119 constant. You didn't, of course, try "2 = 1", because the compiler
2120 catches that. But an easy way to do the same thing is:
2122 sub mod { $_[0] = 1 }
2125 Another way is to assign to a substr() that's off the end of the string.
2127 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2128 is aliased to a constant in the look I<LIST>:
2131 foreach my $n ($x, 2) {
2132 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2135 =item Modification of non-creatable array value attempted, %s
2137 (F) You tried to make an array value spring into existence, and the
2138 subscript was probably negative, even counting from end of the array
2141 =item Modification of non-creatable hash value attempted, %s
2143 (P) You tried to make a hash value spring into existence, and it
2144 couldn't be created for some peculiar reason.
2146 =item Module name must be constant
2148 (F) Only a bare module name is allowed as the first argument to a "use".
2150 =item Module name required with -%c option
2152 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2153 you omitted the name of the module. Consult L<perlrun> for full details
2154 about C<-M> and C<-m>.
2156 =item More than one argument to open
2158 (F) The C<open> function has been asked to open multiple files. This
2159 can happen if you are trying to open a pipe to a command that takes a
2160 list of arguments, but have forgotten to specify a piped open mode.
2161 See L<perlfunc/open> for details.
2163 =item msg%s not implemented
2165 (F) You don't have System V message IPC on your system.
2167 =item Multidimensional syntax %s not supported
2169 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2170 They're written like C<$foo[1][2][3]>, as in C.
2172 =item '/' must be followed by 'a*', 'A*' or 'Z*'
2174 (F) You had a pack template indicating a counted-length string,
2175 Currently the only things that can have their length counted are a*, A*
2176 or Z*. See L<perlfunc/pack>.
2178 =item '/' must follow a numeric type in unpack
2180 (F) You had an unpack template that contained a '/', but this did not
2181 follow some unpack specification producing a numeric value.
2182 See L<perlfunc/pack>.
2184 =item "my sub" not yet implemented
2186 (F) Lexically scoped subroutines are not yet implemented. Don't try
2189 =item "my" variable %s can't be in a package
2191 (F) Lexically scoped variables aren't in a package, so it doesn't make
2192 sense to try to declare one with a package qualifier on the front. Use
2193 local() if you want to localize a package variable.
2195 =item Name "%s::%s" used only once: possible typo
2197 (W once) Typographical errors often show up as unique variable names.
2198 If you had a good reason for having a unique name, then just mention it
2199 again somehow to suppress the message. The C<our> declaration is
2200 provided for this purpose.
2202 =item Negative '/' count in unpack
2204 (F) The length count obtained from a length/code unpack operation was
2205 negative. See L<perlfunc/pack>.
2207 =item Negative length
2209 (F) You tried to do a read/write/send/recv operation with a buffer
2210 length that is less than 0. This is difficult to imagine.
2212 =item Negative offset to vec in lvalue context
2214 (F) When C<vec> is called in an lvalue context, the second argument must be
2215 greater than or equal to zero.
2217 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2219 (F) You can't quantify a quantifier without intervening parentheses. So
2220 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2221 expression about where the problem was discovered.
2223 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2224 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2226 =item %s never introduced
2228 (S internal) The symbol in question was declared but somehow went out of
2229 scope before it could possibly have been used.
2231 =item Newline in left-justified string for %s
2233 (W printf) There is a newline in a string to be left justified by
2234 C<printf> or C<sprintf>.
2236 The padding spaces will appear after the newline, which is probably not
2237 what you wanted. Usually you should remove the newline from the string
2238 and put formatting characters in the C<sprintf> format.
2240 =item No %s allowed while running setuid
2242 (F) Certain operations are deemed to be too insecure for a setuid or
2243 setgid script to even be allowed to attempt. Generally speaking there
2244 will be another way to do what you want that is, if not secure, at least
2245 securable. See L<perlsec>.
2247 =item No comma allowed after %s
2249 (F) A list operator that has a filehandle or "indirect object" is not
2250 allowed to have a comma between that and the following arguments.
2251 Otherwise it'd be just another one of the arguments.
2253 One possible cause for this is that you expected to have imported a
2254 constant to your name space with B<use> or B<import> while no such
2255 importing took place, it may for example be that your operating system
2256 does not support that particular constant. Hopefully you did use an
2257 explicit import list for the constants you expect to see, please see
2258 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2259 would probably have caught this error earlier it naturally does not
2260 remedy the fact that your operating system still does not support that
2261 constant. Maybe you have a typo in the constants of the symbol import
2262 list of B<use> or B<import> or in the constant name at the line where
2263 this error was triggered?
2265 =item No command into which to pipe on command line
2267 (F) An error peculiar to VMS. Perl handles its own command line
2268 redirection, and found a '|' at the end of the command line, so it
2269 doesn't know where you want to pipe the output from this command.
2271 =item No DB::DB routine defined
2273 (F) The currently executing code was compiled with the B<-d> switch, but
2274 for some reason the perl5db.pl file (or some facsimile thereof) didn't
2275 define a routine to be called at the beginning of each statement. Which
2276 is odd, because the file should have been required automatically, and
2277 should have blown up the require if it didn't parse right.
2279 =item No dbm on this machine
2281 (P) This is counted as an internal error, because every machine should
2282 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2284 =item No DBsub routine
2286 (F) The currently executing code was compiled with the B<-d> switch,
2287 but for some reason the perl5db.pl file (or some facsimile thereof)
2288 didn't define a DB::sub routine to be called at the beginning of each
2289 ordinary subroutine call.
2291 =item No B<-e> allowed in setuid scripts
2293 (F) A setuid script can't be specified by the user.
2295 =item No error file after 2> or 2>> on command line
2297 (F) An error peculiar to VMS. Perl handles its own command line
2298 redirection, and found a '2>' or a '2>>' on the command line, but can't
2299 find the name of the file to which to write data destined for stderr.
2301 =item No group ending character '%c' found in template
2303 (F) A pack or unpack template has an opening '(' or '[' without its
2304 matching counterpart. See L<perlfunc/pack>.
2306 =item No input file after < on command line
2308 (F) An error peculiar to VMS. Perl handles its own command line
2309 redirection, and found a '<' on the command line, but can't find the
2310 name of the file from which to read data for stdin.
2314 (F) The setuid emulator requires that scripts have a well-formed #! line
2315 even on machines that don't support the #! construct.
2317 =item "no" not allowed in expression
2319 (F) The "no" keyword is recognized and executed at compile time, and
2320 returns no useful value. See L<perlmod>.
2322 =item No output file after > on command line
2324 (F) An error peculiar to VMS. Perl handles its own command line
2325 redirection, and found a lone '>' at the end of the command line, so it
2326 doesn't know where you wanted to redirect stdout.
2328 =item No output file after > or >> on command line
2330 (F) An error peculiar to VMS. Perl handles its own command line
2331 redirection, and found a '>' or a '>>' on the command line, but can't
2332 find the name of the file to which to write data destined for stdout.
2334 =item No package name allowed for variable %s in "our"
2336 (F) Fully qualified variable names are not allowed in "our"
2337 declarations, because that doesn't make much sense under existing
2338 semantics. Such syntax is reserved for future extensions.
2340 =item No Perl script found in input
2342 (F) You called C<perl -x>, but no line was found in the file beginning
2343 with #! and containing the word "perl".
2345 =item No setregid available
2347 (F) Configure didn't find anything resembling the setregid() call for
2350 =item No setreuid available
2352 (F) Configure didn't find anything resembling the setreuid() call for
2355 =item No space allowed after -%c
2357 (F) The argument to the indicated command line switch must follow
2358 immediately after the switch, without intervening spaces.
2360 =item No %s specified for -%c
2362 (F) The indicated command line switch needs a mandatory argument, but
2363 you haven't specified one.
2365 =item No such class %s
2367 (F) You provided a class qualifier in a "my" or "our" declaration, but
2368 this class doesn't exist at this point in your program.
2370 =item No such pipe open
2372 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
2373 close a pipe which hadn't been opened. This should have been caught
2374 earlier as an attempt to close an unopened filehandle.
2376 =item No such signal: SIG%s
2378 (W signal) You specified a signal name as a subscript to %SIG that was
2379 not recognized. Say C<kill -l> in your shell to see the valid signal
2380 names on your system.
2382 =item Not a CODE reference
2384 (F) Perl was trying to evaluate a reference to a code value (that is, a
2385 subroutine), but found a reference to something else instead. You can
2386 use the ref() function to find out what kind of ref it really was. See
2389 =item Not a format reference
2391 (F) I'm not sure how you managed to generate a reference to an anonymous
2392 format, but this indicates you did, and that it didn't exist.
2394 =item Not a GLOB reference
2396 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
2397 symbol table entry that looks like C<*foo>), but found a reference to
2398 something else instead. You can use the ref() function to find out what
2399 kind of ref it really was. See L<perlref>.
2401 =item Not a HASH reference
2403 (F) Perl was trying to evaluate a reference to a hash value, but found a
2404 reference to something else instead. You can use the ref() function to
2405 find out what kind of ref it really was. See L<perlref>.
2407 =item Not an ARRAY reference
2409 (F) Perl was trying to evaluate a reference to an array value, but found
2410 a reference to something else instead. You can use the ref() function
2411 to find out what kind of ref it really was. See L<perlref>.
2413 =item Not a perl script
2415 (F) The setuid emulator requires that scripts have a well-formed #! line
2416 even on machines that don't support the #! construct. The line must
2419 =item Not a SCALAR reference
2421 (F) Perl was trying to evaluate a reference to a scalar value, but found
2422 a reference to something else instead. You can use the ref() function
2423 to find out what kind of ref it really was. See L<perlref>.
2425 =item Not a subroutine reference
2427 (F) Perl was trying to evaluate a reference to a code value (that is, a
2428 subroutine), but found a reference to something else instead. You can
2429 use the ref() function to find out what kind of ref it really was. See
2432 =item Not a subroutine reference in overload table
2434 (F) An attempt was made to specify an entry in an overloading table that
2435 doesn't somehow point to a valid subroutine. See L<overload>.
2437 =item Not enough arguments for %s
2439 (F) The function requires more arguments than you specified.
2441 =item Not enough format arguments
2443 (W syntax) A format specified more picture fields than the next line
2444 supplied. See L<perlform>.
2448 (A) You've accidentally run your script through the Bourne shell instead
2449 of Perl. Check the #! line, or manually feed your script into Perl
2452 =item no UTC offset information; assuming local time is UTC
2454 (S) A warning peculiar to VMS. Perl was unable to find the local
2455 timezone offset, so it's assuming that local system time is equivalent
2456 to UTC. If it's not, define the logical name
2457 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
2458 need to be added to UTC to get local time.
2460 =item Null filename used
2462 (F) You can't require the null filename, especially because on many
2463 machines that means the current directory! See L<perlfunc/require>.
2465 =item NULL OP IN RUN
2467 (P debugging) Some internal routine called run() with a null opcode
2470 =item Null picture in formline
2472 (F) The first argument to formline must be a valid format picture
2473 specification. It was found to be empty, which probably means you
2474 supplied it an uninitialized value. See L<perlform>.
2478 (P) An attempt was made to realloc NULL.
2480 =item NULL regexp argument
2482 (P) The internal pattern matching routines blew it big time.
2484 =item NULL regexp parameter
2486 (P) The internal pattern matching routines are out of their gourd.
2488 =item Number too long
2490 (F) Perl limits the representation of decimal numbers in programs to
2491 about 250 characters. You've exceeded that length. Future
2492 versions of Perl are likely to eliminate this arbitrary limitation. In
2493 the meantime, try using scientific notation (e.g. "1e6" instead of
2496 =item Octal number in vector unsupported
2498 (F) Numbers with a leading C<0> are not currently allowed in vectors.
2499 The octal number interpretation of such numbers may be supported in a
2502 =item Octal number > 037777777777 non-portable
2504 (W portable) The octal number you specified is larger than 2**32-1
2505 (4294967295) and therefore non-portable between systems. See
2506 L<perlport> for more on portability concerns.
2508 See also L<perlport> for writing portable code.
2510 =item Odd number of arguments for overload::constant
2512 (W overload) The call to overload::constant contained an odd number of
2513 arguments. The arguments should come in pairs.
2515 =item Odd number of elements in anonymous hash
2517 (W misc) You specified an odd number of elements to initialize a hash,
2518 which is odd, because hashes come in key/value pairs.
2520 =item Odd number of elements in hash assignment
2522 (W misc) You specified an odd number of elements to initialize a hash,
2523 which is odd, because hashes come in key/value pairs.
2525 =item Offset outside string
2527 (F) You tried to do a read/write/send/recv operation with an offset
2528 pointing outside the buffer. This is difficult to imagine. The sole
2529 exception to this is that C<sysread()>ing past the buffer will extend
2530 the buffer and zero pad the new area.
2532 =item %s() on unopened %s
2534 (W unopened) An I/O operation was attempted on a filehandle that was
2535 never initialized. You need to do an open(), a sysopen(), or a socket()
2536 call, or call a constructor from the FileHandle package.
2538 =item -%s on unopened filehandle %s
2540 (W unopened) You tried to invoke a file test operator on a filehandle
2541 that isn't open. Check your control flow. See also L<perlfunc/-X>.
2545 (S internal) An internal warning that the grammar is screwed up.
2549 (S internal) An internal warning that the grammar is screwed up.
2551 =item Operation `%s': no method found, %s
2553 (F) An attempt was made to perform an overloaded operation for which no
2554 handler was defined. While some handlers can be autogenerated in terms
2555 of other handlers, there is no default handler for any operation, unless
2556 C<fallback> overloading key is specified to be true. See L<overload>.
2558 =item Operator or semicolon missing before %s
2560 (S ambiguous) You used a variable or subroutine call where the parser
2561 was expecting an operator. The parser has assumed you really meant to
2562 use an operator, but this is highly likely to be incorrect. For
2563 example, if you say "*foo *foo" it will be interpreted as if you said
2566 =item "our" variable %s redeclared
2568 (W misc) You seem to have already declared the same global once before
2569 in the current lexical scope.
2571 =item Out of memory!
2573 (X) The malloc() function returned 0, indicating there was insufficient
2574 remaining memory (or virtual memory) to satisfy the request. Perl has
2575 no option but to exit immediately.
2577 At least in Unix you may be able to get past this by increasing your
2578 process datasize limits: in csh/tcsh use C<limit> and
2579 C<limit datasize n> (where C<n> is the number of kilobytes) to check
2580 the current limits and change them, and in ksh/bash/zsh use C<ulimit -a>
2581 and C<ulimit -d n>, respectively.
2583 =item Out of memory during "large" request for %s
2585 (F) The malloc() function returned 0, indicating there was insufficient
2586 remaining memory (or virtual memory) to satisfy the request. However,
2587 the request was judged large enough (compile-time default is 64K), so a
2588 possibility to shut down by trapping this error is granted.
2590 =item Out of memory during request for %s
2592 (X|F) The malloc() function returned 0, indicating there was
2593 insufficient remaining memory (or virtual memory) to satisfy the
2596 The request was judged to be small, so the possibility to trap it
2597 depends on the way perl was compiled. By default it is not trappable.
2598 However, if compiled for this, Perl may use the contents of C<$^M> as an
2599 emergency pool after die()ing with this message. In this case the error
2600 is trappable I<once>, and the error message will include the line and file
2601 where the failed request happened.
2603 =item Out of memory during ridiculously large request
2605 (F) You can't allocate more than 2^31+"small amount" bytes. This error
2606 is most likely to be caused by a typo in the Perl program. e.g.,
2607 C<$arr[time]> instead of C<$arr[$time]>.
2609 =item Out of memory for yacc stack
2611 (F) The yacc parser wanted to grow its stack so it could continue
2612 parsing, but realloc() wouldn't give it more memory, virtual or
2615 =item '@' outside of string in unpack
2617 (F) You had a template that specified an absolute position outside
2618 the string being unpacked. See L<perlfunc/pack>.
2620 =item %s package attribute may clash with future reserved word: %s
2622 (W reserved) A lowercase attribute name was used that had a
2623 package-specific handler. That name might have a meaning to Perl itself
2624 some day, even though it doesn't yet. Perhaps you should use a
2625 mixed-case attribute name, instead. See L<attributes>.
2627 =item pack/unpack repeat count overflow
2629 (F) You can't specify a repeat count so large that it overflows your
2630 signed integers. See L<perlfunc/pack>.
2634 (W io) A single call to write() produced more lines than can fit on a
2635 page. See L<perlform>.
2639 (P) An internal error.
2641 =item panic: ck_grep
2643 (P) Failed an internal consistency check trying to compile a grep.
2645 =item panic: ck_split
2647 (P) Failed an internal consistency check trying to compile a split.
2649 =item panic: corrupt saved stack index
2651 (P) The savestack was requested to restore more localized values than
2652 there are in the savestack.
2654 =item panic: del_backref
2656 (P) Failed an internal consistency check while trying to reset a weak
2659 =item panic: Devel::DProf inconsistent subroutine return
2661 (P) Devel::DProf called a subroutine that exited using goto(LABEL),
2662 last(LABEL) or next(LABEL). Leaving that way a subroutine called from
2663 an XSUB will lead very probably to a crash of the interpreter. This is
2664 a bug that will hopefully one day get fixed.
2668 (P) We popped the context stack to an eval context, and then discovered
2669 it wasn't an eval context.
2671 =item panic: do_subst
2673 (P) The internal pp_subst() routine was called with invalid operational
2676 =item panic: do_trans_%s
2678 (P) The internal do_trans routines were called with invalid operational
2683 (P) The library function frexp() failed, making printf("%f") impossible.
2687 (P) We popped the context stack to a context with the specified label,
2688 and then discovered it wasn't a context we know how to do a goto in.
2690 =item panic: INTERPCASEMOD
2692 (P) The lexer got into a bad state at a case modifier.
2694 =item panic: INTERPCONCAT
2696 (P) The lexer got into a bad state parsing a string with brackets.
2698 =item panic: kid popen errno read
2700 (F) forked child returned an incomprehensible message about its errno.
2704 (P) We popped the context stack to a block context, and then discovered
2705 it wasn't a block context.
2707 =item panic: leave_scope clearsv
2709 (P) A writable lexical variable became read-only somehow within the
2712 =item panic: leave_scope inconsistency
2714 (P) The savestack probably got out of sync. At least, there was an
2715 invalid enum on the top of it.
2717 =item panic: magic_killbackrefs
2719 (P) Failed an internal consistency check while trying to reset all weak
2720 references to an object.
2724 (P) Something requested a negative number of bytes of malloc.
2726 =item panic: mapstart
2728 (P) The compiler is screwed up with respect to the map() function.
2730 =item panic: null array
2732 (P) One of the internal array routines was passed a null AV pointer.
2734 =item panic: pad_alloc
2736 (P) The compiler got confused about which scratch pad it was allocating
2737 and freeing temporaries and lexicals from.
2739 =item panic: pad_free curpad
2741 (P) The compiler got confused about which scratch pad it was allocating
2742 and freeing temporaries and lexicals from.
2744 =item panic: pad_free po
2746 (P) An invalid scratch pad offset was detected internally.
2748 =item panic: pad_reset curpad
2750 (P) The compiler got confused about which scratch pad it was allocating
2751 and freeing temporaries and lexicals from.
2753 =item panic: pad_sv po
2755 (P) An invalid scratch pad offset was detected internally.
2757 =item panic: pad_swipe curpad
2759 (P) The compiler got confused about which scratch pad it was allocating
2760 and freeing temporaries and lexicals from.
2762 =item panic: pad_swipe po
2764 (P) An invalid scratch pad offset was detected internally.
2766 =item panic: pp_iter
2768 (P) The foreach iterator got called in a non-loop context frame.
2770 =item panic: pp_match%s
2772 (P) The internal pp_match() routine was called with invalid operational
2775 =item panic: pp_split
2777 (P) Something terrible went wrong in setting up for the split.
2779 =item panic: realloc
2781 (P) Something requested a negative number of bytes of realloc.
2783 =item panic: restartop
2785 (P) Some internal routine requested a goto (or something like it), and
2786 didn't supply the destination.
2790 (P) We popped the context stack to a subroutine or eval context, and
2791 then discovered it wasn't a subroutine or eval context.
2793 =item panic: scan_num
2795 (P) scan_num() got called on something that wasn't a number.
2797 =item panic: sv_insert
2799 (P) The sv_insert() routine was told to remove more string than there
2802 =item panic: top_env
2804 (P) The compiler attempted to do a goto, or something weird like that.
2806 =item panic: utf16_to_utf8: odd bytelen
2808 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
2809 to even) byte length.
2813 (P) The lexer got into a bad state while processing a case modifier.
2815 =item Parentheses missing around "%s" list
2817 (W parenthesis) You said something like
2823 my ($foo, $bar) = @_;
2825 Remember that "my", "our", and "local" bind tighter than comma.
2827 =item C<-p> destination: %s
2829 (F) An error occurred during the implicit output invoked by the C<-p>
2830 command-line switch. (This output goes to STDOUT unless you've
2831 redirected it with select().)
2833 =item (perhaps you forgot to load "%s"?)
2835 (F) This is an educated guess made in conjunction with the message
2836 "Can't locate object method \"%s\" via package \"%s\"". It often means
2837 that a method requires a package that has not been loaded.
2839 =item perlio: argument list not closed for layer "%s"
2841 (W layer) When pushing a layer with arguments onto the Perl I/O system you
2842 forgot the ) that closes the argument list. (Layers take care of transforming
2843 data between external and internal representations.) Perl stopped parsing
2844 the layer list at this point and did not attempt to push this layer.
2845 If your program didn't explicitly request the failing operation, it may be
2846 the result of the value of the environment variable PERLIO.
2848 =item perlio: invalid separator character %s in layer specification list %s
2850 (W layer) When pushing layers onto the Perl I/O system, something other than a
2851 colon or whitespace was seen between the elements of a layer list.
2852 If the previous attribute had a parenthesised parameter list, perhaps that
2853 list was terminated too soon.
2855 =item perlio: unknown layer "%s"
2857 (W layer) An attempt was made to push an unknown layer onto the Perl I/O
2858 system. (Layers take care of transforming data between external and
2859 internal representations.) Note that some layers, such as C<mmap>,
2860 are not supported in all environments. If your program didn't
2861 explicitly request the failing operation, it may be the result of the
2862 value of the environment variable PERLIO.
2864 =item Perl %s required--this is only version %s, stopped
2866 (F) The module in question uses features of a version of Perl more
2867 recent than the currently running version. How long has it been since
2868 you upgraded, anyway? See L<perlfunc/require>.
2870 =item PERL_SH_DIR too long
2872 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2873 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
2875 =item PERL_SIGNALS illegal: "%s"
2877 See L<perlrun/PERL_SIGNALS> for legal values.
2879 =item perl: warning: Setting locale failed.
2881 (S) The whole warning message will look something like:
2883 perl: warning: Setting locale failed.
2884 perl: warning: Please check that your locale settings:
2887 are supported and installed on your system.
2888 perl: warning: Falling back to the standard locale ("C").
2890 Exactly what were the failed locale settings varies. In the above the
2891 settings were that the LC_ALL was "En_US" and the LANG had no value.
2892 This error means that Perl detected that you and/or your operating
2893 system supplier and/or system administrator have set up the so-called
2894 locale system but Perl could not use those settings. This was not
2895 dead serious, fortunately: there is a "default locale" called "C" that
2896 Perl can and will use, the script will be run. Before you really fix
2897 the problem, however, you will get the same error message each time
2898 you run Perl. How to really fix the problem can be found in
2899 L<perllocale> section B<LOCALE PROBLEMS>.
2901 =item Permission denied
2903 (F) The setuid emulator in suidperl decided you were up to no good.
2905 =item pid %x not a child
2907 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
2908 process which isn't a subprocess of the current process. While this is
2909 fine from VMS' perspective, it's probably not what you intended.
2911 =item 'P' must have an explicit size in unpack
2913 (F) The unpack format P must have an explicit size, not "*".
2915 =item B<-P> not allowed for setuid/setgid script
2917 (F) The script would have to be opened by the C preprocessor by name,
2918 which provides a race condition that breaks security.
2920 =item POSIX class [:%s:] unknown in regex; marked by <-- HERE in m/%s/
2922 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
2923 shows in the regular expression about where the problem was discovered.
2924 Note that the POSIX character classes do B<not> have the C<is> prefix
2925 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
2926 not C<isprint>. See L<perlre>.
2928 =item POSIX getpgrp can't take an argument
2930 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
2931 the BSD version, which takes a pid.
2933 =item POSIX syntax [%s] belongs inside character classes in regex; marked by <-- HERE in m/%s/
2935 (W regexp) The character class constructs [: :], [= =], and [. .] go
2936 I<inside> character classes, the [] are part of the construct, for example:
2937 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
2938 implemented; they are simply placeholders for future extensions and will
2939 cause fatal errors. The <-- HERE shows in the regular expression about
2940 where the problem was discovered. See L<perlre>.
2942 =item POSIX syntax [. .] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
2944 (F regexp) Within regular expression character classes ([]) the syntax
2945 beginning with "[." and ending with ".]" is reserved for future extensions.
2946 If you need to represent those character sequences inside a regular
2947 expression character class, just quote the square brackets with the
2948 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
2949 about where the problem was discovered. See L<perlre>.
2951 =item POSIX syntax [= =] is reserved for future extensions in regex; marked by <-- HERE in m/%s/
2953 (F) Within regular expression character classes ([]) the syntax beginning
2954 with "[=" and ending with "=]" is reserved for future extensions. If you
2955 need to represent those character sequences inside a regular expression
2956 character class, just quote the square brackets with the backslash: "\[="
2957 and "=\]". The <-- HERE shows in the regular expression about where the
2958 problem was discovered. See L<perlre>.
2960 =item Possible attempt to put comments in qw() list
2962 (W qw) qw() lists contain items separated by whitespace; as with literal
2963 strings, comment characters are not ignored, but are instead treated as
2964 literal data. (You may have used different delimiters than the
2965 parentheses shown here; braces are also frequently used.)
2967 You probably wrote something like this:
2974 when you should have written this:
2981 If you really want comments, build your list the
2982 old-fashioned way, with quotes and commas:
2986 'b', # another comment
2989 =item Possible attempt to separate words with commas
2991 (W qw) qw() lists contain items separated by whitespace; therefore
2992 commas aren't needed to separate the items. (You may have used
2993 different delimiters than the parentheses shown here; braces are also
2996 You probably wrote something like this:
3000 which puts literal commas into some of the list items. Write it without
3001 commas if you don't want them to appear in your data:
3005 =item Possible memory corruption: %s overflowed 3rd argument
3007 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
3008 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
3009 end of the buffer just in case. This sentinel byte got clobbered, and
3010 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
3012 =item Possible precedence problem on bitwise %c operator
3014 (W precedence) Your program uses a bitwise logical operator in conjunction
3015 with a numeric comparison operator, like this :
3017 if ($x & $y == 0) { ... }
3019 This expression is actually equivalent to C<$x & ($y == 0)>, due to the
3020 higher precedence of C<==>. This is probably not what you want. (If you
3021 really meant to write this, disable the warning, or, better, put the
3022 parentheses explicitly and write C<$x & ($y == 0)>).
3024 =item Possible unintended interpolation of %s in string
3026 (W ambiguous) You said something like `@foo' in a double-quoted string
3027 but there was no array C<@foo> in scope at the time. If you wanted a
3028 literal @foo, then write it as \@foo; otherwise find out what happened
3029 to the array you apparently lost track of.
3031 =item Possible Y2K bug: %s
3033 (W y2k) You are concatenating the number 19 with another number, which
3034 could be a potential Year 2000 problem.
3036 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
3038 (D deprecated) You have written something like this:
3042 use attrs qw(locked);
3045 You should use the new declaration syntax instead.
3051 The C<use attrs> pragma is now obsolete, and is only provided for
3052 backward-compatibility. See L<perlsub/"Subroutine Attributes">.
3054 =item Precedence problem: open %s should be open(%s)
3056 (S precedence) The old irregular construct
3060 is now misinterpreted as
3064 because of the strict regularization of Perl 5's grammar into unary and
3065 list operators. (The old open was a little of both.) You must put
3066 parentheses around the filehandle, or use the new "or" operator instead
3069 =item Premature end of script headers
3073 =item printf() on closed filehandle %s
3075 (W closed) The filehandle you're writing to got itself closed sometime
3076 before now. Check your control flow.
3078 =item print() on closed filehandle %s
3080 (W closed) The filehandle you're printing on got itself closed sometime
3081 before now. Check your control flow.
3083 =item Process terminated by SIG%s
3085 (W) This is a standard message issued by OS/2 applications, while *nix
3086 applications die in silence. It is considered a feature of the OS/2
3087 port. One can easily disable this by appropriate sighandlers, see
3088 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
3091 =item Prototype mismatch: %s vs %s
3093 (S prototype) The subroutine being declared or defined had previously been
3094 declared or defined with a different function prototype.
3096 =item Prototype not terminated
3098 (F) You've omitted the closing parenthesis in a function prototype
3101 =item Quantifier follows nothing in regex; marked by <-- HERE in m/%s/
3103 (F) You started a regular expression with a quantifier. Backslash it if you
3104 meant it literally. The <-- HERE shows in the regular expression about
3105 where the problem was discovered. See L<perlre>.
3107 =item Quantifier in {,} bigger than %d in regex; marked by <-- HERE in m/%s/
3109 (F) There is currently a limit to the size of the min and max values of the
3110 {min,max} construct. The <-- HERE shows in the regular expression about where
3111 the problem was discovered. See L<perlre>.
3113 =item Quantifier unexpected on zero-length expression; marked by <-- HERE in m/%s/
3115 (W regexp) You applied a regular expression quantifier in a place where
3116 it makes no sense, such as on a zero-width assertion. Try putting the
3117 quantifier inside the assertion instead. For example, the way to match
3118 "abc" provided that it is followed by three repetitions of "xyz" is
3119 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
3121 The <-- HERE shows in the regular expression about where the problem was
3124 =item Range iterator outside integer range
3126 (F) One (or both) of the numeric arguments to the range operator ".."
3127 are outside the range which can be represented by integers internally.
3128 One possible workaround is to force Perl to use magical string increment
3129 by prepending "0" to your numbers.
3131 =item readline() on closed filehandle %s
3133 (W closed) The filehandle you're reading from got itself closed sometime
3134 before now. Check your control flow.
3136 =item read() on closed filehandle %s
3138 (W closed) You tried to read from a closed filehandle.
3140 =item read() on unopened filehandle %s
3142 (W unopened) You tried to read from a filehandle that was never opened.
3144 =item Reallocation too large: %lx
3146 (F) You can't allocate more than 64K on an MS-DOS machine.
3148 =item realloc() of freed memory ignored
3150 (S malloc) An internal routine called realloc() on something that had
3153 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3155 (F debugging) You can't use the B<-D> option unless the code to produce
3156 the desired output is compiled into Perl, which entails some overhead,
3157 which is why it's currently left out of your copy.
3159 =item Recursive inheritance detected in package '%s'
3161 (F) More than 100 levels of inheritance were used. Probably indicates
3162 an unintended loop in your inheritance hierarchy.
3164 =item Recursive inheritance detected while looking for method %s
3166 (F) More than 100 levels of inheritance were encountered while invoking
3167 a method. Probably indicates an unintended loop in your inheritance
3170 =item Reference found where even-sized list expected
3172 (W misc) You gave a single reference where Perl was expecting a list
3173 with an even number of elements (for assignment to a hash). This usually
3174 means that you used the anon hash constructor when you meant to use
3175 parens. In any case, a hash requires key/value B<pairs>.
3177 %hash = { one => 1, two => 2, }; # WRONG
3178 %hash = [ qw/ an anon array / ]; # WRONG
3179 %hash = ( one => 1, two => 2, ); # right
3180 %hash = qw( one 1 two 2 ); # also fine
3182 =item Reference is already weak
3184 (W misc) You have attempted to weaken a reference that is already weak.
3185 Doing so has no effect.
3187 =item Reference miscount in sv_replace()
3189 (W internal) The internal sv_replace() function was handed a new SV with
3190 a reference count of other than 1.
3192 =item Reference to nonexistent group in regex; marked by <-- HERE in m/%s/
3194 (F) You used something like C<\7> in your regular expression, but there are
3195 not at least seven sets of capturing parentheses in the expression. If you
3196 wanted to have the character with value 7 inserted into the regular expression,
3197 prepend a zero to make the number at least two digits: C<\07>
3199 The <-- HERE shows in the regular expression about where the problem was
3202 =item regexp memory corruption
3204 (P) The regular expression engine got confused by what the regular
3205 expression compiler gave it.
3207 =item Regexp out of space
3209 (P) A "can't happen" error, because safemalloc() should have caught it
3212 =item Reversed %s= operator
3214 (W syntax) You wrote your assignment operator backwards. The = must
3215 always comes last, to avoid ambiguity with subsequent unary operators.
3217 =item Runaway format
3219 (F) Your format contained the ~~ repeat-until-blank sequence, but it
3220 produced 200 lines at once, and the 200th line looked exactly like the
3221 199th line. Apparently you didn't arrange for the arguments to exhaust
3222 themselves, either by using ^ instead of @ (for scalar variables), or by
3223 shifting or popping (for array variables). See L<perlform>.
3225 =item Scalars leaked: %d
3227 (P) Something went wrong in Perl's internal bookkeeping of scalars:
3228 not all scalar variables were deallocated by the time Perl exited.
3229 What this usually indicates is a memory leak, which is of course bad,
3230 especially if the Perl program is intended to be long-running.
3232 =item Scalar value @%s[%s] better written as $%s[%s]
3234 (W syntax) You've used an array slice (indicated by @) to select a
3235 single element of an array. Generally it's better to ask for a scalar
3236 value (indicated by $). The difference is that C<$foo[&bar]> always
3237 behaves like a scalar, both when assigning to it and when evaluating its
3238 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
3239 and provides a list context to its subscript, which can do weird things
3240 if you're expecting only one subscript.
3242 On the other hand, if you were actually hoping to treat the array
3243 element as a list, you need to look into how references work, because
3244 Perl will not magically convert between scalars and lists for you. See
3247 =item Scalar value @%s{%s} better written as $%s{%s}
3249 (W syntax) You've used a hash slice (indicated by @) to select a single
3250 element of a hash. Generally it's better to ask for a scalar value
3251 (indicated by $). The difference is that C<$foo{&bar}> always behaves
3252 like a scalar, both when assigning to it and when evaluating its
3253 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
3254 and provides a list context to its subscript, which can do weird things
3255 if you're expecting only one subscript.
3257 On the other hand, if you were actually hoping to treat the hash element
3258 as a list, you need to look into how references work, because Perl will
3259 not magically convert between scalars and lists for you. See
3262 =item Script is not setuid/setgid in suidperl
3264 (F) Oddly, the suidperl program was invoked on a script without a setuid
3265 or setgid bit set. This doesn't make much sense.
3267 =item Search pattern not terminated
3269 (F) The lexer couldn't find the final delimiter of a // or m{}
3270 construct. Remember that bracketing delimiters count nesting level.
3271 Missing the leading C<$> from a variable C<$m> may cause this error.
3273 Note that since Perl 5.9.0 a // can also be the I<defined-or>
3274 construct, not just the empty search pattern. Therefore code written
3275 in Perl 5.9.0 or later that uses the // as the I<defined-or> can be
3276 misparsed by pre-5.9.0 Perls as a non-terminated search pattern.
3278 =item %sseek() on unopened filehandle
3280 (W unopened) You tried to use the seek() or sysseek() function on a
3281 filehandle that was either never opened or has since been closed.
3283 =item select not implemented
3285 (F) This machine doesn't implement the select() system call.
3287 =item Self-ties of arrays and hashes are not supported
3289 (F) Self-ties are of arrays and hashes are not supported in
3290 the current implementation.
3292 =item Semicolon seems to be missing
3294 (W semicolon) A nearby syntax error was probably caused by a missing
3295 semicolon, or possibly some other missing operator, such as a comma.
3297 =item semi-panic: attempt to dup freed string
3299 (S internal) The internal newSVsv() routine was called to duplicate a
3300 scalar that had previously been marked as free.
3302 =item sem%s not implemented
3304 (F) You don't have System V semaphore IPC on your system.
3306 =item send() on closed socket %s
3308 (W closed) The socket you're sending to got itself closed sometime
3309 before now. Check your control flow.
3311 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
3313 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
3314 shows in the regular expression about where the problem was discovered. See
3317 =item Sequence (?%s...) not implemented in regex; marked by <-- HERE in m/%s/
3319 (F) A proposed regular expression extension has the character reserved but
3320 has not yet been written. The <-- HERE shows in the regular expression about
3321 where the problem was discovered. See L<perlre>.
3323 =item Sequence (?%s...) not recognized in regex; marked by <-- HERE in m/%s/
3325 (F) You used a regular expression extension that doesn't make sense. The
3326 <-- HERE shows in the regular expression about where the problem was
3327 discovered. See L<perlre>.
3329 =item Sequence (?#... not terminated in regex; marked by <-- HERE in m/%s/
3331 (F) A regular expression comment must be terminated by a closing
3332 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
3333 the regular expression about where the problem was discovered. See
3336 =item Sequence (?{...}) not terminated or not {}-balanced in regex; marked by <-- HERE in m/%s/
3338 (F) If the contents of a (?{...}) clause contains braces, they must balance
3339 for Perl to properly detect the end of the clause. The <-- HERE shows in
3340 the regular expression about where the problem was discovered. See
3343 =item 500 Server error
3349 This is the error message generally seen in a browser window when trying
3350 to run a CGI program (including SSI) over the web. The actual error text
3351 varies widely from server to server. The most frequently-seen variants
3352 are "500 Server error", "Method (something) not permitted", "Document
3353 contains no data", "Premature end of script headers", and "Did not
3354 produce a valid header".
3356 B<This is a CGI error, not a Perl error>.
3358 You need to make sure your script is executable, is accessible by the
3359 user CGI is running the script under (which is probably not the user
3360 account you tested it under), does not rely on any environment variables
3361 (like PATH) from the user it isn't running under, and isn't in a
3362 location where the CGI server can't find it, basically, more or less.
3363 Please see the following for more information:
3365 http://www.perl.org/CGI_MetaFAQ.html
3366 http://www.htmlhelp.org/faq/cgifaq.html
3367 http://www.w3.org/Security/Faq/
3369 You should also look at L<perlfaq9>.
3371 =item setegid() not implemented
3373 (F) You tried to assign to C<$)>, and your operating system doesn't
3374 support the setegid() system call (or equivalent), or at least Configure
3377 =item seteuid() not implemented
3379 (F) You tried to assign to C<< $> >>, and your operating system doesn't
3380 support the seteuid() system call (or equivalent), or at least Configure
3383 =item setpgrp can't take arguments
3385 (F) Your system has the setpgrp() from BSD 4.2, which takes no
3386 arguments, unlike POSIX setpgid(), which takes a process ID and process
3389 =item setrgid() not implemented
3391 (F) You tried to assign to C<$(>, and your operating system doesn't
3392 support the setrgid() system call (or equivalent), or at least Configure
3395 =item setruid() not implemented
3397 (F) You tried to assign to C<$<>, and your operating system doesn't
3398 support the setruid() system call (or equivalent), or at least Configure
3401 =item setsockopt() on closed socket %s
3403 (W closed) You tried to set a socket option on a closed socket. Did you
3404 forget to check the return value of your socket() call? See
3405 L<perlfunc/setsockopt>.
3407 =item Setuid/gid script is writable by world
3409 (F) The setuid emulator won't run a script that is writable by the
3410 world, because the world might have written on it already.
3412 =item shm%s not implemented
3414 (F) You don't have System V shared memory IPC on your system.
3416 =item <> should be quotes
3418 (F) You wrote C<< require <file> >> when you should have written
3421 =item /%s/ should probably be written as "%s"
3423 (W syntax) You have used a pattern where Perl expected to find a string,
3424 as in the first argument to C<join>. Perl will treat the true or false
3425 result of matching the pattern against $_ as the string, which is
3426 probably not what you had in mind.
3428 =item shutdown() on closed socket %s
3430 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
3433 =item SIG%s handler "%s" not defined
3435 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
3436 Perhaps you put it into the wrong package?
3438 =item sort is now a reserved word
3440 (F) An ancient error message that almost nobody ever runs into anymore.
3441 But before sort was a keyword, people sometimes used it as a filehandle.
3443 =item Sort subroutine didn't return a numeric value
3445 (F) A sort comparison routine must return a number. You probably blew
3446 it by not using C<< <=> >> or C<cmp>, or by not using them correctly.
3447 See L<perlfunc/sort>.
3449 =item Sort subroutine didn't return single value
3451 (F) A sort comparison subroutine may not return a list value with more
3452 or less than one element. See L<perlfunc/sort>.
3454 =item splice() offset past end of array
3456 (W misc) You attempted to specify an offset that was past the end of
3457 the array passed to splice(). Splicing will instead commence at the end
3458 of the array, rather than past it. If this isn't what you want, try
3459 explicitly pre-extending the array by assigning $#array = $offset. See
3464 (P) The split was looping infinitely. (Obviously, a split shouldn't
3465 iterate more times than there are characters of input, which is what
3466 happened.) See L<perlfunc/split>.
3468 =item Statement unlikely to be reached
3470 (W exec) You did an exec() with some statement after it other than a
3471 die(). This is almost always an error, because exec() never returns
3472 unless there was a failure. You probably wanted to use system()
3473 instead, which does return. To suppress this warning, put the exec() in
3476 =item stat() on unopened filehandle %s
3478 (W unopened) You tried to use the stat() function on a filehandle that
3479 was either never opened or has since been closed.
3481 =item Stub found while resolving method `%s' overloading %s
3483 (P) Overloading resolution over @ISA tree may be broken by importation
3484 stubs. Stubs should never be implicitly created, but explicit calls to
3485 C<can> may break this.
3487 =item Subroutine %s redefined
3489 (W redefine) You redefined a subroutine. To suppress this warning, say
3492 no warnings 'redefine';
3493 eval "sub name { ... }";
3496 =item Substitution loop
3498 (P) The substitution was looping infinitely. (Obviously, a substitution
3499 shouldn't iterate more times than there are characters of input, which
3500 is what happened.) See the discussion of substitution in
3501 L<perlop/"Quote and Quote-like Operators">.
3503 =item Substitution pattern not terminated
3505 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
3506 construct. Remember that bracketing delimiters count nesting level.
3507 Missing the leading C<$> from variable C<$s> may cause this error.
3509 =item Substitution replacement not terminated
3511 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
3512 construct. Remember that bracketing delimiters count nesting level.
3513 Missing the leading C<$> from variable C<$s> may cause this error.
3515 =item substr outside of string
3517 (W substr),(F) You tried to reference a substr() that pointed outside of
3518 a string. That is, the absolute value of the offset was larger than the
3519 length of the string. See L<perlfunc/substr>. This warning is fatal if
3520 substr is used in an lvalue context (as the left hand side of an
3521 assignment or as a subroutine argument for example).
3523 =item suidperl is no longer needed since %s
3525 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but
3526 a version of the setuid emulator somehow got run anyway.
3528 =item Switch (?(condition)... contains too many branches in regex; marked by <-- HERE in m/%s/
3530 (F) A (?(condition)if-clause|else-clause) construct can have at most two
3531 branches (the if-clause and the else-clause). If you want one or both to
3532 contain alternation, such as using C<this|that|other>, enclose it in
3533 clustering parentheses:
3535 (?(condition)(?:this|that|other)|else-clause)
3537 The <-- HERE shows in the regular expression about where the problem was
3538 discovered. See L<perlre>.
3540 =item Switch condition not recognized in regex; marked by <-- HERE in m/%s/
3542 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
3543 number, it can be only a number. The <-- HERE shows in the regular expression
3544 about where the problem was discovered. See L<perlre>.
3546 =item switching effective %s is not implemented
3548 (F) While under the C<use filetest> pragma, we cannot switch the real
3549 and effective uids or gids.
3553 (F) The final summary message when a C<perl -c> succeeds.
3557 (F) Probably means you had a syntax error. Common reasons include:
3559 A keyword is misspelled.
3560 A semicolon is missing.
3562 An opening or closing parenthesis is missing.
3563 An opening or closing brace is missing.
3564 A closing quote is missing.
3566 Often there will be another error message associated with the syntax
3567 error giving more information. (Sometimes it helps to turn on B<-w>.)
3568 The error message itself often tells you where it was in the line when
3569 it decided to give up. Sometimes the actual error is several tokens
3570 before this, because Perl is good at understanding random input.
3571 Occasionally the line number may be misleading, and once in a blue moon
3572 the only way to figure out what's triggering the error is to call
3573 C<perl -c> repeatedly, chopping away half the program each time to see
3574 if the error went away. Sort of the cybernetic version of S<20
3577 =item syntax error at line %d: `%s' unexpected
3579 (A) You've accidentally run your script through the Bourne shell instead
3580 of Perl. Check the #! line, or manually feed your script into Perl
3583 =item syntax error in file %s at line %d, next 2 tokens "%s"
3585 (F) This error is likely to occur if you run a perl5 script through
3586 a perl4 interpreter, especially if the next 2 tokens are "use strict"
3587 or "my $var" or "our $var".
3589 =item sysread() on closed filehandle %s
3591 (W closed) You tried to read from a closed filehandle.
3593 =item sysread() on unopened filehandle %s
3595 (W unopened) You tried to read from a filehandle that was never opened.
3597 =item System V %s is not implemented on this machine
3599 (F) You tried to do something with a function beginning with "sem",
3600 "shm", or "msg" but that System V IPC is not implemented in your
3601 machine. In some machines the functionality can exist but be
3602 unconfigured. Consult your system support.
3604 =item syswrite() on closed filehandle %s
3606 (W closed) The filehandle you're writing to got itself closed sometime
3607 before now. Check your control flow.
3609 =item C<-T> and C<-B> not implemented on filehandles
3611 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
3612 know about your kind of stdio. You'll have to use a filename instead.
3614 =item Target of goto is too deeply nested
3616 (F) You tried to use C<goto> to reach a label that was too deeply nested
3617 for Perl to reach. Perl is doing you a favor by refusing.
3619 =item tell() on unopened filehandle
3621 (W unopened) You tried to use the tell() function on a filehandle that
3622 was either never opened or has since been closed.
3624 =item That use of $[ is unsupported
3626 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
3627 as a compiler directive. You may say only one of
3636 This is to prevent the problem of one module changing the array base out
3637 from under another module inadvertently. See L<perlvar/$[>.
3639 =item The crypt() function is unimplemented due to excessive paranoia
3641 (F) Configure couldn't find the crypt() function on your machine,
3642 probably because your vendor didn't supply it, probably because they
3643 think the U.S. Government thinks it's a secret, or at least that they
3644 will continue to pretend that it is. And if you quote me on that, I
3647 =item The %s function is unimplemented
3649 The function indicated isn't implemented on this architecture, according
3650 to the probings of Configure.
3652 =item The stat preceding %s wasn't an lstat
3654 (F) It makes no sense to test the current stat buffer for symbolic
3655 linkhood if the last stat that wrote to the stat buffer already went
3656 past the symlink to get to the real file. Use an actual filename
3659 =item This Perl can't reset CRTL environ elements (%s)
3661 =item This Perl can't set CRTL environ elements (%s=%s)
3663 (W internal) Warnings peculiar to VMS. You tried to change or delete an
3664 element of the CRTL's internal environ array, but your copy of Perl
3665 wasn't built with a CRTL that contained the setenv() function. You'll
3666 need to rebuild Perl with a CRTL that does, or redefine
3667 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
3668 target of the change to
3669 %ENV which produced the warning.
3671 =item thread failed to start: %s
3673 (F) The entry point function of threads->create() failed for some reason.
3675 =item Tied variable freed while still in use
3677 (F) An access method for a tied variable (e.g. FETCH) did something to
3678 free the variable. Since continuing the current operation is likely
3679 to result in a coredump, Perl is bailing out instead.
3681 =item times not implemented
3683 (F) Your version of the C library apparently doesn't do times(). I
3684 suspect you're not running on Unix.
3686 =item To%s: illegal mapping '%s'
3688 (F) You tried to define a customized To-mapping for lc(), lcfirst,
3689 uc(), or ucfirst() (or their string-inlined versions), but you
3690 specified an illegal mapping.
3691 See L<perlunicode/"User-Defined Character Properties">.
3693 =item Too deeply nested ()-groups
3695 (F) Your template contains ()-groups with a ridiculously deep nesting level.
3697 =item Too few args to syscall
3699 (F) There has to be at least one argument to syscall() to specify the
3700 system call to call, silly dilly.
3702 =item Too late for "-%s" option
3704 (X) The #! line (or local equivalent) in a Perl script contains the
3705 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
3706 are not intended for use inside scripts. Use the C<use> pragma instead.
3708 =item Too late for "B<-T>" option
3710 (X) The #! line (or local equivalent) in a Perl script contains the
3711 B<-T> option, but Perl was not invoked with B<-T> in its command line.
3712 This is an error because, by the time Perl discovers a B<-T> in a
3713 script, it's too late to properly taint everything from the environment.
3716 If the Perl script is being executed as a command using the #!
3717 mechanism (or its local equivalent), this error can usually be fixed by
3718 editing the #! line so that the B<-T> option is a part of Perl's first
3719 argument: e.g. change C<perl -n -T> to C<perl -T -n>.
3721 If the Perl script is being executed as C<perl scriptname>, then the
3722 B<-T> option must appear on the command line: C<perl -T scriptname>.
3724 =item Too late to run %s block
3726 (W void) A CHECK or INIT block is being defined during run time proper,
3727 when the opportunity to run them has already passed. Perhaps you are
3728 loading a file with C<require> or C<do> when you should be using C<use>
3729 instead. Or perhaps you should put the C<require> or C<do> inside a
3732 =item Too many args to syscall
3734 (F) Perl supports a maximum of only 14 args to syscall().
3736 =item Too many arguments for %s
3738 (F) The function requires fewer arguments than you specified.
3742 (A) You've accidentally run your script through B<csh> instead of Perl.
3743 Check the #! line, or manually feed your script into Perl yourself.
3747 (A) You've accidentally run your script through B<csh> instead of Perl.
3748 Check the #! line, or manually feed your script into Perl yourself.
3750 =item Trailing \ in regex m/%s/
3752 (F) The regular expression ends with an unbackslashed backslash.
3753 Backslash it. See L<perlre>.
3755 =item Transliteration pattern not terminated
3757 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
3758 or y/// or y[][] construct. Missing the leading C<$> from variables
3759 C<$tr> or C<$y> may cause this error.
3761 =item Transliteration replacement not terminated
3763 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
3766 =item '%s' trapped by operation mask
3768 (F) You tried to use an operator from a Safe compartment in which it's
3769 disallowed. See L<Safe>.
3771 =item truncate not implemented
3773 (F) Your machine doesn't implement a file truncation mechanism that
3774 Configure knows about.
3776 =item Type of arg %d to %s must be %s (not %s)
3778 (F) This function requires the argument in that position to be of a
3779 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
3780 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
3781 {EXPR} forms as an explicit dereference. See L<perlref>.
3783 =item umask not implemented
3785 (F) Your machine doesn't implement the umask function and you tried to
3786 use it to restrict permissions for yourself (EXPR & 0700).
3788 =item Unable to create sub named "%s"
3790 (F) You attempted to create or access a subroutine with an illegal name.
3792 =item Unbalanced context: %d more PUSHes than POPs
3794 (W internal) The exit code detected an internal inconsistency in how
3795 many execution contexts were entered and left.
3797 =item Unbalanced saves: %d more saves than restores
3799 (W internal) The exit code detected an internal inconsistency in how
3800 many values were temporarily localized.
3802 =item Unbalanced scopes: %d more ENTERs than LEAVEs
3804 (W internal) The exit code detected an internal inconsistency in how
3805 many blocks were entered and left.
3807 =item Unbalanced tmps: %d more allocs than frees
3809 (W internal) The exit code detected an internal inconsistency in how
3810 many mortal scalars were allocated and freed.
3812 =item Undefined format "%s" called
3814 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3815 another package? See L<perlform>.
3817 =item Undefined sort subroutine "%s" called
3819 (F) The sort comparison routine specified doesn't seem to exist.
3820 Perhaps it's in a different package? See L<perlfunc/sort>.
3822 =item Undefined subroutine &%s called
3824 (F) The subroutine indicated hasn't been defined, or if it was, it has
3825 since been undefined.
3827 =item Undefined subroutine called
3829 (F) The anonymous subroutine you're trying to call hasn't been defined,
3830 or if it was, it has since been undefined.
3832 =item Undefined subroutine in sort
3834 (F) The sort comparison routine specified is declared but doesn't seem
3835 to have been defined yet. See L<perlfunc/sort>.
3837 =item Undefined top format "%s" called
3839 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3840 another package? See L<perlform>.
3842 =item Undefined value assigned to typeglob
3844 (W misc) An undefined value was assigned to a typeglob, a la
3845 C<*foo = undef>. This does nothing. It's possible that you really mean
3848 =item %s: Undefined variable
3850 (A) You've accidentally run your script through B<csh> instead of Perl.
3851 Check the #! line, or manually feed your script into Perl yourself.
3853 =item unexec of %s into %s failed!
3855 (F) The unexec() routine failed for some reason. See your local FSF
3856 representative, who probably put it there in the first place.
3858 =item Unicode character %s is illegal
3860 (W utf8) Certain Unicode characters have been designated off-limits by
3861 the Unicode standard and should not be generated. If you really know
3862 what you are doing you can turn off this warning by C<no warnings 'utf8';>.
3864 =item Unknown BYTEORDER
3866 (F) There are no byte-swapping functions for a machine with this byte
3869 =item Unknown open() mode '%s'
3871 (F) The second argument of 3-argument open() is not among the list
3872 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
3873 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->, C<< <& >>, C<< >& >>.
3875 =item Unknown process %x sent message to prime_env_iter: %s
3877 (P) An error peculiar to VMS. Perl was reading values for %ENV before
3878 iterating over it, and someone else stuck a message in the stream of
3879 data Perl expected. Someone's very confused, or perhaps trying to
3880 subvert Perl's population of %ENV for nefarious purposes.
3882 =item Unknown "re" subpragma '%s' (known ones are: %s)
3884 You tried to use an unknown subpragma of the "re" pragma.
3886 =item Unknown switch condition (?(%.2s in regex; marked by <-- HERE in m/%s/
3888 (F) The condition part of a (?(condition)if-clause|else-clause) construct
3889 is not known. The condition may be lookahead or lookbehind (the condition
3890 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
3891 condition is true if the code evaluates to a true value), or a number (the
3892 condition is true if the set of capturing parentheses named by the number
3895 The <-- HERE shows in the regular expression about where the problem was
3896 discovered. See L<perlre>.
3898 =item Unknown Unicode option letter '%c'
3900 You specified an unknown Unicode option. See L<perlrun> documentation
3901 of the C<-C> switch for the list of known options.
3903 =item Unknown Unicode option value %x
3905 You specified an unknown Unicode option. See L<perlrun> documentation
3906 of the C<-C> switch for the list of known options.
3908 =item Unknown warnings category '%s'
3910 (F) An error issued by the C<warnings> pragma. You specified a warnings
3911 category that is unknown to perl at this point.
3913 Note that if you want to enable a warnings category registered by a module
3914 (e.g. C<use warnings 'File::Find'>), you must have imported this module
3917 =item unmatched [ in regex; marked by <-- HERE in m/%s/
3919 (F) The brackets around a character class must match. If you wish to
3920 include a closing bracket in a character class, backslash it or put it
3921 first. The <-- HERE shows in the regular expression about where the problem
3922 was discovered. See L<perlre>.
3924 =item unmatched ( in regex; marked by <-- HERE in m/%s/
3926 (F) Unbackslashed parentheses must always be balanced in regular
3927 expressions. If you're a vi user, the % key is valuable for finding the
3928 matching parenthesis. The <-- HERE shows in the regular expression about
3929 where the problem was discovered. See L<perlre>.
3931 =item Unmatched right %s bracket
3933 (F) The lexer counted more closing curly or square brackets than opening
3934 ones, so you're probably missing a matching opening bracket. As a
3935 general rule, you'll find the missing one (so to speak) near the place
3936 you were last editing.
3938 =item Unquoted string "%s" may clash with future reserved word
3940 (W reserved) You used a bareword that might someday be claimed as a
3941 reserved word. It's best to put such a word in quotes, or capitalize it
3942 somehow, or insert an underbar into it. You might also declare it as a
3945 =item Unrecognized character %s
3947 (F) The Perl parser has no idea what to do with the specified character
3948 in your Perl script (or eval). Perhaps you tried to run a compressed
3949 script, a binary program, or a directory as a Perl program.
3951 =item /%s/: Unrecognized escape \\%c in character class passed through
3953 (W regexp) You used a backslash-character combination which is not
3954 recognized by Perl inside character classes. The character was
3955 understood literally.
3957 =item Unrecognized escape \\%c passed through
3959 (W misc) You used a backslash-character combination which is not
3962 =item Unrecognized escape \\%c passed through in regex; marked by <-- HERE in m/%s/
3964 (W regexp) You used a backslash-character combination which is not
3965 recognized by Perl. This combination appears in an interpolated variable or
3966 a C<'>-delimited regular expression. The character was understood
3967 literally. The <-- HERE shows in the regular expression about where the
3968 escape was discovered.
3970 =item Unrecognized signal name "%s"
3972 (F) You specified a signal name to the kill() function that was not
3973 recognized. Say C<kill -l> in your shell to see the valid signal names
3976 =item Unrecognized switch: -%s (-h will show valid options)
3978 (F) You specified an illegal option to Perl. Don't do that. (If you
3979 think you didn't do that, check the #! line to see if it's supplying the
3980 bad switch on your behalf.)
3982 =item Unsuccessful %s on filename containing newline
3984 (W newline) A file operation was attempted on a filename, and that
3985 operation failed, PROBABLY because the filename contained a newline,
3986 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
3988 =item Unsupported directory function "%s" called
3990 (F) Your machine doesn't support opendir() and readdir().
3992 =item Unsupported function %s
3994 (F) This machine doesn't implement the indicated function, apparently.
3995 At least, Configure doesn't think so.
3997 =item Unsupported function fork
3999 (F) Your version of executable does not support forking.
4001 Note that under some systems, like OS/2, there may be different flavors
4002 of Perl executables, some of which may support fork, some not. Try
4003 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
4005 =item Unsupported script encoding
4007 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
4008 declares it to be in a Unicode encoding that Perl cannot yet read.
4010 =item Unsupported socket function "%s" called
4012 (F) Your machine doesn't support the Berkeley socket mechanism, or at
4013 least that's what Configure thought.
4015 =item Unterminated attribute list
4017 (F) The lexer found something other than a simple identifier at the
4018 start of an attribute, and it wasn't a semicolon or the start of a
4019 block. Perhaps you terminated the parameter list of the previous
4020 attribute too soon. See L<attributes>.
4022 =item Unterminated attribute parameter in attribute list
4024 (F) The lexer saw an opening (left) parenthesis character while parsing
4025 an attribute list, but the matching closing (right) parenthesis
4026 character was not found. You may need to add (or remove) a backslash
4027 character to get your parentheses to balance. See L<attributes>.
4029 =item Unterminated compressed integer
4031 (F) An argument to unpack("w",...) was incompatible with the BER
4032 compressed integer format and could not be converted to an integer.
4033 See L<perlfunc/pack>.
4035 =item Unterminated <> operator
4037 (F) The lexer saw a left angle bracket in a place where it was expecting
4038 a term, so it's looking for the corresponding right angle bracket, and
4039 not finding it. Chances are you left some needed parentheses out
4040 earlier in the line, and you really meant a "less than".
4042 =item untie attempted while %d inner references still exist
4044 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
4045 still valid when C<untie> was called.
4047 =item Usage: POSIX::%s(%s)
4049 (F) You called a POSIX function with incorrect arguments.
4050 See L<POSIX/FUNCTIONS> for more information.
4052 =item Usage: Win32::%s(%s)
4054 (F) You called a Win32 function with incorrect arguments.
4055 See L<Win32> for more information.
4057 =item Useless (?-%s) - don't use /%s modifier in regex; marked by <-- HERE in m/%s/
4059 (W regexp) You have used an internal modifier such as (?-o) that has no
4060 meaning unless removed from the entire regexp:
4062 if ($string =~ /(?-o)$pattern/o) { ... }
4066 if ($string =~ /$pattern/) { ... }
4068 The <-- HERE shows in the regular expression about
4069 where the problem was discovered. See L<perlre>.
4071 =item Useless (?%s) - use /%s modifier in regex; marked by <-- HERE in m/%s/
4073 (W regexp) You have used an internal modifier such as (?o) that has no
4074 meaning unless applied to the entire regexp:
4076 if ($string =~ /(?o)$pattern/) { ... }
4080 if ($string =~ /$pattern/o) { ... }
4082 The <-- HERE shows in the regular expression about
4083 where the problem was discovered. See L<perlre>.
4085 =item Useless localization of %s
4087 (W syntax) The localization of lvalues such as C<local($x=10)> is
4088 legal, but in fact the local() currently has no effect. This may change at
4089 some point in the future, but in the meantime such code is discouraged.
4091 =item Useless use of %s in void context
4093 (W void) You did something without a side effect in a context that does
4094 nothing with the return value, such as a statement that doesn't return a
4095 value from a block, or the left side of a scalar comma operator. Very
4096 often this points not to stupidity on your part, but a failure of Perl
4097 to parse your program the way you thought it would. For example, you'd
4098 get this if you mixed up your C precedence with Python precedence and
4103 when you meant to say
4105 ($one, $two) = (1, 2);
4107 Another common error is to use ordinary parentheses to construct a list
4108 reference when you should be using square or curly brackets, for
4113 when you should have said
4117 The square brackets explicitly turn a list value into a scalar value,
4118 while parentheses do not. So when a parenthesized list is evaluated in
4119 a scalar context, the comma is treated like C's comma operator, which
4120 throws away the left argument, which is not what you want. See
4121 L<perlref> for more on this.
4123 This warning will not be issued for numerical constants equal to 0 or 1
4124 since they are often used in statements like
4126 1 while sub_with_side_effects() ;
4128 String constants that would normally evaluate to 0 or 1 are warned
4131 =item Useless use of "re" pragma
4133 (W) You did C<use re;> without any arguments. That isn't very useful.
4135 =item Useless use of sort in scalar context
4137 (W void) You used sort in scalar context, as in :
4141 This is not very useful, and perl currently optimizes this away.
4143 =item Useless use of %s with no values
4145 (W syntax) You used the push() or unshift() function with no arguments
4146 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
4147 usually have any effect on the array, so is completely useless. It's
4148 possible in principle that push(@tied_array) could have some effect
4149 if the array is tied to a class which implements a PUSH method. If so,
4150 you can write it as C<push(@tied_array,())> to avoid this warning.
4152 =item "use" not allowed in expression
4154 (F) The "use" keyword is recognized and executed at compile time, and
4155 returns no useful value. See L<perlmod>.
4157 =item Use of bare << to mean <<"" is deprecated
4159 (D deprecated) You are now encouraged to use the explicitly quoted form
4160 if you wish to use an empty line as the terminator of the here-document.
4162 =item Use of chdir('') or chdir(undef) as chdir() deprecated
4164 (D deprecated) chdir() with no arguments is documented to change to
4165 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
4166 behavior, but that has been deprecated. In future versions they
4169 Be careful to check that what you pass to chdir() is defined and not
4170 blank, else you might find yourself in your home directory.
4172 =item Use of /c modifier is meaningless in s///
4174 (W regexp) You used the /c modifier in a substitution. The /c
4175 modifier is not presently meaningful in substitutions.
4177 =item Use of /c modifier is meaningless without /g
4179 (W regexp) You used the /c modifier with a regex operand, but didn't
4180 use the /g modifier. Currently, /c is meaningful only when /g is
4181 used. (This may change in the future.)
4183 =item Use of freed value in iteration (perhaps you modified the iterated array within the loop?)
4185 (F) This is typically caused by code like the following:
4188 @a = () for (1,2,@a);
4190 You are not supposed to modify arrays while they are being iterated over.
4191 For speed and efficiency reasons, Perl internally does not do full
4192 reference-counting of iterated items, hence deleting such an item in the
4193 middle of an iteration causes Perl to see a freed value.
4195 =item Use of *glob{FILEHANDLE} is deprecated
4197 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
4198 to access the filehandle slot within a typeglob.
4200 =item Use of /g modifier is meaningless in split
4202 (W regexp) You used the /g modifier on the pattern for a C<split>
4203 operator. Since C<split> always tries to match the pattern
4204 repeatedly, the C</g> has no effect.
4206 =item Use of implicit split to @_ is deprecated
4208 (D deprecated) It makes a lot of work for the compiler when you clobber
4209 a subroutine's argument list, so it's better if you assign the results
4210 of a split() explicitly to an array (or list).
4212 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
4214 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
4215 are looked up as methods (using the C<@ISA> hierarchy) even when the
4216 subroutines to be autoloaded were called as plain functions (e.g.
4217 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
4220 This bug will be rectified in future by using method lookup only for
4221 methods' C<AUTOLOAD>s. However, there is a significant base of existing
4222 code that may be using the old behavior. So, as an interim step, Perl
4223 currently issues an optional warning when non-methods use inherited
4226 The simple rule is: Inheritance will not work when autoloading
4227 non-methods. The simple fix for old code is: In any module that used
4228 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
4229 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
4232 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
4233 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
4234 C<use AutoLoader 'AUTOLOAD';>.
4236 =item Use of %s in printf format not supported
4238 (F) You attempted to use a feature of printf that is accessible from
4239 only C. This usually means there's a better way to do it in Perl.
4241 =item Use of $# is deprecated
4243 (D deprecated) This was an ill-advised attempt to emulate a poorly
4244 defined B<awk> feature. Use an explicit printf() or sprintf() instead.
4246 =item Use of %s is deprecated
4248 (D deprecated) The construct indicated is no longer recommended for use,
4249 generally because there's a better way to do it, and also because the
4250 old way has bad side effects.
4252 =item Use of -l on filehandle %s
4254 (W io) A filehandle represents an opened file, and when you opened the file
4255 it already went past any symlink you are presumably trying to look for.
4256 The operation returned C<undef>. Use a filename instead.
4258 =item Use of "package" with no arguments is deprecated
4260 (D deprecated) You used the C<package> keyword without specifying a package
4261 name. So no namespace is current at all. Using this can cause many
4262 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
4265 =item Use of reference "%s" as array index
4267 (W misc) You tried to use a reference as an array index; this probably
4268 isn't what you mean, because references in numerical context tend
4269 to be huge numbers, and so usually indicates programmer error.
4271 If you really do mean it, explicitly numify your reference, like so:
4272 C<$array[0+$ref]>. This warning is not given for overloaded objects,
4273 either, because you can overload the numification and stringification
4274 operators and then you assumedly know what you are doing.
4276 =item Use of reserved word "%s" is deprecated
4278 (D deprecated) The indicated bareword is a reserved word. Future
4279 versions of perl may use it as a keyword, so you're better off either
4280 explicitly quoting the word in a manner appropriate for its context of
4281 use, or using a different name altogether. The warning can be
4282 suppressed for subroutine names by either adding a C<&> prefix, or using
4283 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
4285 =item Use of tainted arguments in %s is deprecated
4287 (W taint, deprecated) You have supplied C<system()> or C<exec()> with multiple
4288 arguments and at least one of them is tainted. This used to be allowed
4289 but will become a fatal error in a future version of perl. Untaint your
4290 arguments. See L<perlsec>.
4292 =item Use of uninitialized value%s
4294 (W uninitialized) An undefined value was used as if it were already
4295 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
4296 To suppress this warning assign a defined value to your variables.
4298 To help you figure out what was undefined, perl tells you what operation
4299 you used the undefined value in. Note, however, that perl optimizes your
4300 program and the operation displayed in the warning may not necessarily
4301 appear literally in your program. For example, C<"that $foo"> is
4302 usually optimized into C<"that " . $foo>, and the warning will refer to
4303 the C<concatenation (.)> operator, even though there is no C<.> in your
4306 =item Using a hash as a reference is deprecated
4308 (D deprecated) You tried to use a hash as a reference, as in
4309 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
4310 used to allow this syntax, but shouldn't have. It is now deprecated, and will
4311 be removed in a future version.
4313 =item Using an array as a reference is deprecated
4315 (D deprecated) You tried to use an array as a reference, as in
4316 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
4317 allow this syntax, but shouldn't have. It is now deprecated, and will be
4318 removed in a future version.
4320 =item UTF-16 surrogate %s
4322 (W utf8) You tried to generate half of an UTF-16 surrogate by
4323 requesting a Unicode character between the code points 0xD800 and
4324 0xDFFF (inclusive). That range is reserved exclusively for the use of
4325 UTF-16 encoding (by having two 16-bit UCS-2 characters); but Perl
4326 encodes its characters in UTF-8, so what you got is a very illegal
4327 character. If you really know what you are doing you can turn off
4328 this warning by C<no warnings 'utf8';>.
4330 =item Value of %s can be "0"; test with defined()
4332 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
4333 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
4334 can return a value of "0"; that would make the conditional expression
4335 false, which is probably not what you intended. When using these
4336 constructs in conditional expressions, test their values with the
4337 C<defined> operator.
4339 =item Value of CLI symbol "%s" too long
4341 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
4342 %ENV element from a CLI symbol table, and found a resultant string
4343 longer than 1024 characters. The return value has been truncated to
4346 =item Variable "%s" is not imported%s
4348 (F) While "use strict" in effect, you referred to a global variable that
4349 you apparently thought was imported from another module, because
4350 something else of the same name (usually a subroutine) is exported by
4351 that module. It usually means you put the wrong funny character on the
4352 front of your variable.
4354 =item Variable length lookbehind not implemented in regex; marked by <-- HERE in m/%s/
4356 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
4357 known at compile time. The <-- HERE shows in the regular expression about
4358 where the problem was discovered. See L<perlre>.
4360 =item "%s" variable %s masks earlier declaration in same %s
4362 (W misc) A "my" or "our" variable has been redeclared in the current
4363 scope or statement, effectively eliminating all access to the previous
4364 instance. This is almost always a typographical error. Note that the
4365 earlier variable will still exist until the end of the scope or until
4366 all closure referents to it are destroyed.
4368 =item Variable "%s" is not available
4370 (W closure) During compilation, an inner named subroutine or eval is
4371 attempting to capture an outer lexical that is not currently available.
4372 This can be happen for one of two reasons. First, the outer lexical may be
4373 declared in an outer anonymous subroutine that has not yet been created.
4374 (Remember that named subs are created at compile time, while anonymous
4375 subs are created at run-time. For example,
4377 sub { my $a; sub f { $a } }
4379 At the time that f is created, it can't capture the current value of $a,
4380 since the anonymous subroutine hasn't been created yet. Conversely,
4381 the following won't give a warning since the anonymous subroutine has by
4382 now been created and is live:
4384 sub { my $a; eval 'sub f { $a }' }->();
4386 The second situation is caused by an eval accessing a variable that has
4387 gone out of scope, for example,
4395 Here, when the '$a' in the eval is being compiled, f() is not currently being
4396 executed, so its $a is not available for capture.
4398 =item Variable syntax
4400 (A) You've accidentally run your script through B<csh> instead
4401 of Perl. Check the #! line, or manually feed your script into
4404 =item Variable "%s" will not stay shared
4406 (W closure) An inner (nested) I<named> subroutine is referencing a
4407 lexical variable defined in an outer named subroutine.
4409 When the inner subroutine is called, it will see the value of
4410 the outer subroutine's variable as it was before and during the *first*
4411 call to the outer subroutine; in this case, after the first call to the
4412 outer subroutine is complete, the inner and outer subroutines will no
4413 longer share a common value for the variable. In other words, the
4414 variable will no longer be shared.
4416 This problem can usually be solved by making the inner subroutine
4417 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
4418 reference variables in outer subroutines are created, they
4419 are automatically rebound to the current values of such variables.
4421 =item Version number must be a constant number
4423 (P) The attempt to translate a C<use Module n.n LIST> statement into
4424 its equivalent C<BEGIN> block found an internal inconsistency with
4427 =item v-string in use/require is non-portable
4429 (W portable) The use of v-strings is non-portable to older, pre-5.6, Perls.
4430 If you want your scripts to be backward portable, use the floating
4431 point version number: for example, instead of C<use 5.6.1> say
4432 C<use 5.006_001>. This of course won't help: the older Perls
4433 won't suddenly start understanding newer features, but at least
4434 they will show a sensible error message indicating the required
4437 =item Warning: something's wrong
4439 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
4440 you called it with no args and C<$_> was empty.
4442 =item Warning: unable to close filehandle %s properly
4444 (S) The implicit close() done by an open() got an error indication on
4445 the close(). This usually indicates your file system ran out of disk
4448 =item Warning: Use of "%s" without parentheses is ambiguous
4450 (S ambiguous) You wrote a unary operator followed by something that
4451 looks like a binary operator that could also have been interpreted as a
4452 term or unary operator. For instance, if you know that the rand
4453 function has a default argument of 1.0, and you write
4457 you may THINK you wrote the same thing as
4461 but in actual fact, you got
4465 So put in parentheses to say what you really mean.
4467 =item Wide character in %s
4469 (W utf8) Perl met a wide character (>255) when it wasn't expecting
4470 one. This warning is by default on for I/O (like print) but can be
4471 turned off by C<no warnings 'utf8';>. You are supposed to explicitly
4472 mark the filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
4474 =item Within []-length '%c' not allowed
4476 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
4477 C<TEMPLATE> always matches the same amount of packed bytes that can be
4478 determined from the template alone. This is not possible if it contains an
4479 of the codes @, /, U, u, w or a *-length. Redesign the template.
4481 =item write() on closed filehandle %s
4483 (W closed) The filehandle you're writing to got itself closed sometime
4484 before now. Check your control flow.
4486 =item 'X' outside of string
4488 (F) You had a (un)pack template that specified a relative position before
4489 the beginning of the string being (un)packed. See L<perlfunc/pack>.
4491 =item 'x' outside of string in unpack
4493 (F) You had a pack template that specified a relative position after
4494 the end of the string being unpacked. See L<perlfunc/pack>.
4496 =item Xsub "%s" called in sort
4498 (F) The use of an external subroutine as a sort comparison is not yet
4501 =item Xsub called in sort
4503 (F) The use of an external subroutine as a sort comparison is not yet
4506 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
4508 (F) And you probably never will, because you probably don't have the
4509 sources to your kernel, and your vendor probably doesn't give a rip
4510 about what you want. Your best bet is to put a setuid C wrapper around
4513 =item You need to quote "%s"
4515 (W syntax) You assigned a bareword as a signal handler name.
4516 Unfortunately, you already have a subroutine of that name declared,
4517 which means that Perl 5 will try to call the subroutine when the
4518 assignment is executed, which is probably not what you want. (If it IS
4519 what you want, put an & in front.)