1 //depot/perl/pod/perldiag.pod#272 - edit change 14824 (text)
4 perldiag - various Perl diagnostics
8 These messages are classified as follows (listed in increasing order of
11 (W) A warning (optional).
12 (D) A deprecation (optional).
13 (S) A severe warning (default).
14 (F) A fatal error (trappable).
15 (P) An internal error you should never see (trappable).
16 (X) A very fatal error (nontrappable).
17 (A) An alien error message (not generated by Perl).
19 The majority of messages from the first three classifications above
20 (W, D & S) can be controlled using the C<warnings> pragma.
22 If a message can be controlled by the C<warnings> pragma, its warning
23 category is included with the classification letter in the description
26 Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
27 and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
28 to a reference to a routine that will be called on each warning instead
29 of printing it. See L<perlvar>.
31 Default warnings are always enabled unless they are explicitly disabled
32 with the C<warnings> pragma or the B<-X> switch.
34 Trappable errors may be trapped using the eval operator. See
35 L<perlfunc/eval>. In almost all cases, warnings may be selectively
36 disabled or promoted to fatal errors using the C<warnings> pragma.
39 The messages are in alphabetical order, without regard to upper or
40 lower-case. Some of these messages are generic. Spots that vary are
41 denoted with a %s or other printf-style escape. These escapes are
42 ignored by the alphabetical order, as are all characters other than
43 letters. To look up your message, just ignore anything that is not a
48 =item accept() on closed socket %s
50 (W closed) You tried to do an accept on a closed socket. Did you forget
51 to check the return value of your socket() call? See
54 =item Allocation too large: %lx
56 (X) You can't allocate more than 64K on an MS-DOS machine.
58 =item '!' allowed only after types %s
60 (F) The '!' is allowed in pack() and unpack() only after certain types.
63 =item Ambiguous call resolved as CORE::%s(), qualify as such or use &
65 (W ambiguous) A subroutine you have declared has the same name as a Perl
66 keyword, and you have used the name without qualification for calling
67 one or the other. Perl decided to call the builtin because the
68 subroutine is not imported.
70 To force interpretation as a subroutine call, either put an ampersand
71 before the subroutine name, or qualify the name with its package.
72 Alternatively, you can import the subroutine (or pretend that it's
73 imported with the C<use subs> pragma).
75 To silently interpret it as the Perl operator, use the C<CORE::> prefix
76 on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
77 to be an object method (see L<perlsub/"Subroutine Attributes"> or
80 =item Ambiguous range in transliteration operator
82 (F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
83 all. To include a C<-> character in a transliteration, put it either
84 first or last. (In the past, C<tr/a-z-0//> was synonymous with
85 C<tr/a-y//>, which was probably not what you would have expected.)
87 =item Ambiguous use of %s resolved as %s
89 (W ambiguous)(S) You said something that may not be interpreted the way
90 you thought. Normally it's pretty easy to disambiguate it by supplying
91 a missing quote, operator, parenthesis pair or declaration.
93 =item '|' and '<' may not both be specified on command line
95 (F) An error peculiar to VMS. Perl does its own command line
96 redirection, and found that STDIN was a pipe, and that you also tried to
97 redirect STDIN using '<'. Only one STDIN stream to a customer, please.
99 =item '|' and '>' may not both be specified on command line
101 (F) An error peculiar to VMS. Perl does its own command line
102 redirection, and thinks you tried to redirect stdout both to a file and
103 into a pipe to another command. You need to choose one or the other,
104 though nothing's stopping you from piping into a program or Perl script
105 which 'splits' output into two streams, such as
107 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
114 =item Applying %s to %s will act on scalar(%s)
116 (W misc) The pattern match (C<//>), substitution (C<s///>), and
117 transliteration (C<tr///>) operators work on scalar values. If you apply
118 one of them to an array or a hash, it will convert the array or hash to
119 a scalar value -- the length of an array, or the population info of a
120 hash -- and then work on that scalar value. This is probably not what
121 you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
124 =item Args must match #! line
126 (F) The setuid emulator requires that the arguments Perl was invoked
127 with match the arguments specified on the #! line. Since some systems
128 impose a one-argument limit on the #! line, try combining switches;
129 for example, turn C<-w -U> into C<-wU>.
131 =item Arg too short for msgsnd
133 (F) msgsnd() requires a string at least as long as sizeof(long).
135 =item %s argument is not a HASH or ARRAY element
137 (F) The argument to exists() must be a hash or array element, such as:
142 =item %s argument is not a HASH or ARRAY element or slice
144 (F) The argument to delete() must be either a hash or array element,
150 or a hash or array slice, such as:
152 @foo[$bar, $baz, $xyzzy]
153 @{$ref->[12]}{"susie", "queue"}
155 =item %s argument is not a subroutine name
157 (F) The argument to exists() for C<exists &sub> must be a subroutine
158 name, and not a subroutine call. C<exists &sub()> will generate this
161 =item Argument "%s" isn't numeric%s
163 (W numeric) The indicated string was fed as an argument to an operator
164 that expected a numeric value instead. If you're fortunate the message
165 will identify which operator was so unfortunate.
167 =item Array @%s missing the @ in argument %d of %s()
169 (D deprecated) Really old Perl let you omit the @ on array names in some
170 spots. This is now heavily deprecated.
172 =item assertion botched: %s
174 (P) The malloc package that comes with Perl had an internal failure.
176 =item Assertion failed: file "%s"
178 (P) A general assertion failed. The file in question must be examined.
180 =item Assignment to both a list and a scalar
182 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
183 must either both be scalars or both be lists. Otherwise Perl won't
184 know which context to supply to the right side.
186 =item Attempt to access disallowed key '%s' in a fixed hash
188 (F) The failing code has attempted to get or set a key which is not in
189 the current set of allowed keys of a fixed hash.
191 =item Attempt to clear a fixed hash
193 (F) It is currently not allowed to clear a fixed hash, even if the
194 new hash would contain the same keys as before. This may change in
197 =item Attempt to delete readonly key '%s' from a fixed hash
199 (F) The failing code attempted to delete a key whose value has been
200 declared readonly from a fixed hash.
202 =item Attempt to delete disallowed key '%s' from a fixed hash
204 (F) The failing code attempted to delete from a fixed hash a key which
205 is not in its key set.
207 =item Attempt to bless into a reference
209 (F) The CLASSNAME argument to the bless() operator is expected to be
210 the name of the package to bless the resulting object into. You've
211 supplied instead a reference to something: perhaps you wrote
217 bless $self, ref($proto) || $proto;
219 If you actually want to bless into the stringified version
220 of the reference supplied, you need to stringify it yourself, for
223 bless $self, "$proto";
225 =item Attempt to free non-arena SV: 0x%lx
227 (P internal) All SV objects are supposed to be allocated from arenas
228 that will be garbage collected on exit. An SV was discovered to be
229 outside any of those arenas.
231 =item Attempt to free nonexistent shared string
233 (P internal) Perl maintains a reference counted internal table of
234 strings to optimize the storage and access of hash keys and other
235 strings. This indicates someone tried to decrement the reference count
236 of a string that can no longer be found in the table.
238 =item Attempt to free temp prematurely
240 (W debugging) Mortalized values are supposed to be freed by the
241 free_tmps() routine. This indicates that something else is freeing the
242 SV before the free_tmps() routine gets a chance, which means that the
243 free_tmps() routine will be freeing an unreferenced scalar when it does
246 =item Attempt to free unreferenced glob pointers
248 (P internal) The reference counts got screwed up on symbol aliases.
250 =item Attempt to free unreferenced scalar
252 (W internal) Perl went to decrement the reference count of a scalar to
253 see if it would go to 0, and discovered that it had already gone to 0
254 earlier, and should have been freed, and in fact, probably was freed.
255 This could indicate that SvREFCNT_dec() was called too many times, or
256 that SvREFCNT_inc() was called too few times, or that the SV was
257 mortalized when it shouldn't have been, or that memory has been
260 =item Attempt to join self
262 (F) You tried to join a thread from within itself, which is an
263 impossible task. You may be joining the wrong thread, or you may need
264 to move the join() to some other thread.
266 =item Attempt to pack pointer to temporary value
268 (W pack) You tried to pass a temporary value (like the result of a
269 function, or a computed expression) to the "p" pack() template. This
270 means the result contains a pointer to a location that could become
271 invalid anytime, even before the end of the current statement. Use
272 literals or global values as arguments to the "p" pack() template to
275 =item Attempt to use reference as lvalue in substr
277 (W substr) You supplied a reference as the first argument to substr()
278 used as an lvalue, which is pretty strange. Perhaps you forgot to
279 dereference it first. See L<perlfunc/substr>.
281 =item Bad arg length for %s, is %d, should be %s
283 (F) You passed a buffer of the wrong size to one of msgctl(), semctl()
284 or shmctl(). In C parlance, the correct sizes are, respectively,
285 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
286 S<sizeof(struct shmid_ds *)>.
288 =item Bad evalled substitution pattern
290 (F) You've used the C</e> switch to evaluate the replacement for a
291 substitution, but perl found a syntax error in the code to evaluate,
292 most likely an unexpected right brace '}'.
294 =item Bad filehandle: %s
296 (F) A symbol was passed to something wanting a filehandle, but the
297 symbol has no filehandle associated with it. Perhaps you didn't do an
298 open(), or did it in another package.
300 =item Bad free() ignored
302 (S malloc) An internal routine called free() on something that had never
303 been malloc()ed in the first place. Mandatory, but can be disabled by
304 setting environment variable C<PERL_BADFREE> to 0.
306 This message can be seen quite often with DB_File on systems with "hard"
307 dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
308 which is left unnoticed if C<DB> uses I<forgiving> system malloc().
312 (P) One of the internal hash routines was passed a null HV pointer.
314 =item Bad index while coercing array into hash
316 (F) The index looked up in the hash found as the 0'th element of a
317 pseudo-hash is not legal. Index values must be at 1 or greater.
320 =item Badly placed ()'s
322 (A) You've accidentally run your script through B<csh> instead
323 of Perl. Check the #! line, or manually feed your script into
326 =item Bad name after %s::
328 (F) You started to name a symbol by using a package prefix, and then
329 didn't finish the symbol. In particular, you can't interpolate outside
338 $sym = "mypack::$var";
340 =item Bad realloc() ignored
342 (S malloc) An internal routine called realloc() on something that had
343 never been malloc()ed in the first place. Mandatory, but can be disabled
344 by setting environment variable C<PERL_BADFREE> to 1.
346 =item Bad symbol for array
348 (P) An internal request asked to add an array entry to something that
349 wasn't a symbol table entry.
351 =item Bad symbol for filehandle
353 (P) An internal request asked to add a filehandle entry to something
354 that wasn't a symbol table entry.
356 =item Bad symbol for hash
358 (P) An internal request asked to add a hash entry to something that
359 wasn't a symbol table entry.
361 =item Bareword found in conditional
363 (W bareword) The compiler found a bareword where it expected a
364 conditional, which often indicates that an || or && was parsed as part
365 of the last argument of the previous construct, for example:
369 It may also indicate a misspelled constant that has been interpreted as
372 use constant TYPO => 1;
373 if (TYOP) { print "foo" }
375 The C<strict> pragma is useful in avoiding such errors.
377 =item Bareword "%s" not allowed while "strict subs" in use
379 (F) With "strict subs" in use, a bareword is only allowed as a
380 subroutine identifier, in curly brackets or to the left of the "=>"
381 symbol. Perhaps you need to predeclare a subroutine?
383 =item Bareword "%s" refers to nonexistent package
385 (W bareword) You used a qualified bareword of the form C<Foo::>, but the
386 compiler saw no other uses of that namespace before that point. Perhaps
387 you need to predeclare a package?
389 =item BEGIN failed--compilation aborted
391 (F) An untrapped exception was raised while executing a BEGIN
392 subroutine. Compilation stops immediately and the interpreter is
395 =item BEGIN not safe after errors--compilation aborted
397 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
398 implies a C<BEGIN {}>) after one or more compilation errors had already
399 occurred. Since the intended environment for the C<BEGIN {}> could not
400 be guaranteed (due to the errors), and since subsequent code likely
401 depends on its correct operation, Perl just gave up.
403 =item \1 better written as $1
405 (W syntax) Outside of patterns, backreferences live on as variables.
406 The use of backslashes is grandfathered on the right-hand side of a
407 substitution, but stylistically it's better to use the variable form
408 because other Perl programmers will expect it, and it works better if
409 there are more than 9 backreferences.
411 =item Binary number > 0b11111111111111111111111111111111 non-portable
413 (W portable) The binary number you specified is larger than 2**32-1
414 (4294967295) and therefore non-portable between systems. See
415 L<perlport> for more on portability concerns.
417 =item bind() on closed socket %s
419 (W closed) You tried to do a bind on a closed socket. Did you forget to
420 check the return value of your socket() call? See L<perlfunc/bind>.
422 =item binmode() on closed filehandle %s
424 (W unopened) You tried binmode() on a filehandle that was never opened.
425 Check you control flow and number of arguments.
427 =item Bit vector size > 32 non-portable
429 (W portable) Using bit vector sizes larger than 32 is non-portable.
431 =item Bizarre copy of %s in %s
433 (P) Perl detected an attempt to copy an internal value that is not
436 =item B<-P> not allowed for setuid/setgid script
438 (F) The script would have to be opened by the C preprocessor by name,
439 which provides a race condition that breaks security.
441 =item Buffer overflow in prime_env_iter: %s
443 (W internal) A warning peculiar to VMS. While Perl was preparing to
444 iterate over %ENV, it encountered a logical name or symbol definition
445 which was too long, so it was truncated to the string shown.
447 =item Callback called exit
449 (F) A subroutine invoked from an external package via call_sv()
450 exited by calling exit.
452 =item %s() called too early to check prototype
454 (W prototype) You've called a function that has a prototype before the
455 parser saw a definition or declaration for it, and Perl could not check
456 that the call conforms to the prototype. You need to either add an
457 early prototype declaration for the subroutine in question, or move the
458 subroutine definition ahead of the call to get proper prototype
459 checking. Alternatively, if you are certain that you're calling the
460 function correctly, you may put an ampersand before the name to avoid
461 the warning. See L<perlsub>.
463 =item / cannot take a count
465 (F) You had an unpack template indicating a counted-length string, but
466 you have also specified an explicit size for the string. See
469 =item Can't bless non-reference value
471 (F) Only hard references may be blessed. This is how Perl "enforces"
472 encapsulation of objects. See L<perlobj>.
474 =item Can't call method "%s" in empty package "%s"
476 (F) You called a method correctly, and it correctly indicated a package
477 functioning as a class, but that package doesn't have ANYTHING defined
478 in it, let alone methods. See L<perlobj>.
480 =item Can't call method "%s" on an undefined value
482 (F) You used the syntax of a method call, but the slot filled by the
483 object reference or package name contains an undefined value. Something
484 like this will reproduce the error:
487 process $BADREF 1,2,3;
488 $BADREF->process(1,2,3);
490 =item Can't call method "%s" on unblessed reference
492 (F) A method call must know in what package it's supposed to run. It
493 ordinarily finds this out from the object reference you supply, but you
494 didn't supply an object reference in this case. A reference isn't an
495 object reference until it has been blessed. See L<perlobj>.
497 =item Can't call method "%s" without a package or object reference
499 (F) You used the syntax of a method call, but the slot filled by the
500 object reference or package name contains an expression that returns a
501 defined value which is neither an object reference nor a package name.
502 Something like this will reproduce the error:
505 process $BADREF 1,2,3;
506 $BADREF->process(1,2,3);
508 =item Can't chdir to %s
510 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
511 that you can chdir to, possibly because it doesn't exist.
513 =item Can't check filesystem of script "%s" for nosuid
515 (P) For some reason you can't check the filesystem of the script for
518 =item Can't coerce array into hash
520 (F) You used an array where a hash was expected, but the array has no
521 information on how to map from keys to array indices. You can do that
522 only with arrays that have a hash reference at index 0.
524 =item Can't coerce %s to integer in %s
526 (F) Certain types of SVs, in particular real symbol table entries
527 (typeglobs), can't be forced to stop being what they are. So you can't
537 but then $foo no longer contains a glob.
539 =item Can't coerce %s to number in %s
541 (F) Certain types of SVs, in particular real symbol table entries
542 (typeglobs), can't be forced to stop being what they are.
544 =item Can't coerce %s to string in %s
546 (F) Certain types of SVs, in particular real symbol table entries
547 (typeglobs), can't be forced to stop being what they are.
549 =item Can't create pipe mailbox
551 (P) An error peculiar to VMS. The process is suffering from exhausted
552 quotas or other plumbing problems.
554 =item Can't declare class for non-scalar %s in "%s"
556 (F) Currently, only scalar variables can be declared with a specific
557 class qualifier in a "my" or "our" declaration. The semantics may be
558 extended for other types of variables in future.
560 =item Can't declare %s in "%s"
562 (F) Only scalar, array, and hash variables may be declared as "my" or
563 "our" variables. They must have ordinary identifiers as names.
565 =item Can't do inplace edit: %s is not a regular file
567 (S inplace) You tried to use the B<-i> switch on a special file, such as
568 a file in /dev, or a FIFO. The file was ignored.
570 =item Can't do inplace edit on %s: %s
572 (S inplace) The creation of the new file failed for the indicated
575 =item Can't do inplace edit without backup
577 (F) You're on a system such as MS-DOS that gets confused if you try
578 reading from a deleted (but still opened) file. You have to say
579 C<-i.bak>, or some such.
581 =item Can't do inplace edit: %s would not be unique
583 (S inplace) Your filesystem does not support filenames longer than 14
584 characters and Perl was unable to create a unique filename during
585 inplace editing with the B<-i> switch. The file was ignored.
587 =item Can't do {n,m} with n > m in regex; marked by <-- HERE in m/%s/
589 (F) Minima must be less than or equal to maxima. If you really want your
590 regexp to match something 0 times, just put {0}. The <-- HERE shows in the
591 regular expression about where the problem was discovered. See L<perlre>.
593 =item Can't do setegid!
595 (P) The setegid() call failed for some reason in the setuid emulator of
598 =item Can't do seteuid!
600 (P) The setuid emulator of suidperl failed for some reason.
602 =item Can't do setuid
604 (F) This typically means that ordinary perl tried to exec suidperl to do
605 setuid emulation, but couldn't exec it. It looks for a name of the form
606 sperl5.000 in the same directory that the perl executable resides under
607 the name perl5.000, typically /usr/local/bin on Unix machines. If the
608 file is there, check the execute permissions. If it isn't, ask your
609 sysadmin why he and/or she removed it.
611 =item Can't do waitpid with flags
613 (F) This machine doesn't have either waitpid() or wait4(), so only
614 waitpid() without flags is emulated.
616 =item Can't emulate -%s on #! line
618 (F) The #! line specifies a switch that doesn't make sense at this
619 point. For example, it'd be kind of silly to put a B<-x> on the #!
622 =item Can't exec "%s": %s
624 (W exec) A system(), exec(), or piped open call could not execute the
625 named program for the indicated reason. Typical reasons include: the
626 permissions were wrong on the file, the file wasn't found in
627 C<$ENV{PATH}>, the executable in question was compiled for another
628 architecture, or the #! line in a script points to an interpreter that
629 can't be run for similar reasons. (Or maybe your system doesn't support
634 (F) Perl was trying to execute the indicated program for you because
635 that's what the #! line said. If that's not what you wanted, you may
636 need to mention "perl" on the #! line somewhere.
638 =item Can't execute %s
640 (F) You used the B<-S> switch, but the copies of the script to execute
641 found in the PATH did not have correct permissions.
643 =item Can't find an opnumber for "%s"
645 (F) A string of a form C<CORE::word> was given to prototype(), but there
646 is no builtin with the name C<word>.
648 =item Can't find %s character property "%s"
650 (F) You used C<\p{}> or C<\P{}> but the character property by that name
651 could not be found. Maybe you misspelled the name of the property
652 (remember that the names of character properties consist only of
653 alphanumeric characters), or maybe you forgot the C<Is> or C<In> prefix?
655 =item Can't find label %s
657 (F) You said to goto a label that isn't mentioned anywhere that it's
658 possible for us to go to. See L<perlfunc/goto>.
660 =item Can't find %s on PATH
662 (F) You used the B<-S> switch, but the script to execute could not be
665 =item Can't find %s on PATH, '.' not in PATH
667 (F) You used the B<-S> switch, but the script to execute could not be
668 found in the PATH, or at least not with the correct permissions. The
669 script exists in the current directory, but PATH prohibits running it.
671 =item Can't find string terminator %s anywhere before EOF
673 (F) Perl strings can stretch over multiple lines. This message means
674 that the closing delimiter was omitted. Because bracketed quotes count
675 nesting levels, the following is missing its final parenthesis:
677 print q(The character '(' starts a side comment.);
679 If you're getting this error from a here-document, you may have included
680 unseen whitespace before or after your closing tag. A good programmer's
681 editor will have a way to help you find these characters.
683 =item Can't find %s property definition %s
685 (F) You may have tried to use C<\p> which means a Unicode property for
686 example \p{Lu} is all uppercase letters. Escape the C<\p>, either
687 C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, until
692 (F) A fatal error occurred while trying to fork while opening a
695 =item Can't get filespec - stale stat buffer?
697 (S) A warning peculiar to VMS. This arises because of the difference
698 between access checks under VMS and under the Unix model Perl assumes.
699 Under VMS, access checks are done by filename, rather than by bits in
700 the stat buffer, so that ACLs and other protections can be taken into
701 account. Unfortunately, Perl assumes that the stat buffer contains all
702 the necessary information, and passes it, instead of the filespec, to
703 the access checking routine. It will try to retrieve the filespec using
704 the device name and FID present in the stat buffer, but this works only
705 if you haven't made a subsequent call to the CRTL stat() routine,
706 because the device name is overwritten with each call. If this warning
707 appears, the name lookup failed, and the access checking routine gave up
708 and returned FALSE, just to be conservative. (Note: The access checking
709 routine knows about the Perl C<stat> operator and file tests, so you
710 shouldn't ever see this warning in response to a Perl command; it arises
711 only if some internal code takes stat buffers lightly.)
713 =item Can't get pipe mailbox device name
715 (P) An error peculiar to VMS. After creating a mailbox to act as a
716 pipe, Perl can't retrieve its name for later use.
718 =item Can't get SYSGEN parameter value for MAXBUF
720 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
721 mailbox buffers to be, and didn't get an answer.
723 =item Can't "goto" into the middle of a foreach loop
725 (F) A "goto" statement was executed to jump into the middle of a foreach
726 loop. You can't get there from here. See L<perlfunc/goto>.
728 =item Can't "goto" out of a pseudo block
730 (F) A "goto" statement was executed to jump out of what might look like
731 a block, except that it isn't a proper block. This usually occurs if
732 you tried to jump out of a sort() block or subroutine, which is a no-no.
733 See L<perlfunc/goto>.
735 =item Can't goto subroutine from an eval-string
737 (F) The "goto subroutine" call can't be used to jump out of an eval
738 "string". (You can use it to jump out of an eval {BLOCK}, but you
739 probably don't want to.)
741 =item Can't goto subroutine outside a subroutine
743 (F) The deeply magical "goto subroutine" call can only replace one
744 subroutine call for another. It can't manufacture one out of whole
745 cloth. In general you should be calling it out of only an AUTOLOAD
746 routine anyway. See L<perlfunc/goto>.
748 =item Can't ignore signal CHLD, forcing to default
750 (W signal) Perl has detected that it is being run with the SIGCHLD
751 signal (sometimes known as SIGCLD) disabled. Since disabling this
752 signal will interfere with proper determination of exit status of child
753 processes, Perl has reset the signal to its default value. This
754 situation typically indicates that the parent program under which Perl
755 may be running (e.g. cron) is being very careless.
757 =item Can't "last" outside a loop block
759 (F) A "last" statement was executed to break out of the current block,
760 except that there's this itty bitty problem called there isn't a current
761 block. Note that an "if" or "else" block doesn't count as a "loopish"
762 block, as doesn't a block given to sort(), map() or grep(). You can
763 usually double the curlies to get the same effect though, because the
764 inner curlies will be considered a block that loops once. See
767 =item Can't localize lexical variable %s
769 (F) You used local on a variable name that was previously declared as a
770 lexical variable using "my". This is not allowed. If you want to
771 localize a package variable of the same name, qualify it with the
774 =item Can't localize pseudo-hash element
776 (F) You said something like C<< local $ar->{'key'} >>, where $ar is a
777 reference to a pseudo-hash. That hasn't been implemented yet, but you
778 can get a similar effect by localizing the corresponding array element
779 directly -- C<< local $ar->[$ar->[0]{'key'}] >>.
781 =item Can't localize through a reference
783 (F) You said something like C<local $$ref>, which Perl can't currently
784 handle, because when it goes to restore the old value of whatever $ref
785 pointed to after the scope of the local() is finished, it can't be sure
786 that $ref will still be a reference.
788 =item Can't locate %s
790 (F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be
791 found. Perl looks for the file in all the locations mentioned in @INC,
792 unless the file name included the full path to the file. Perhaps you
793 need to set the PERL5LIB or PERL5OPT environment variable to say where
794 the extra library is, or maybe the script needs to add the library name
795 to @INC. Or maybe you just misspelled the name of the file. See
796 L<perlfunc/require> and L<lib>.
798 =item Can't locate auto/%s.al in @INC
800 (F) A function (or method) was called in a package which allows
801 autoload, but there is no function to autoload. Most probable causes
802 are a misprint in a function/method name or a failure to C<AutoSplit>
803 the file, say, by doing C<make install>.
805 =item Can't locate object method "%s" via package "%s"
807 (F) You called a method correctly, and it correctly indicated a package
808 functioning as a class, but that package doesn't define that particular
809 method, nor does any of its base classes. See L<perlobj>.
811 =item (perhaps you forgot to load "%s"?)
813 (F) This is an educated guess made in conjunction with the message
814 "Can't locate object method \"%s\" via package \"%s\"". It often means
815 that a method requires a package that has not been loaded.
817 =item Can't locate package %s for @%s::ISA
819 (W syntax) The @ISA array contained the name of another package that
820 doesn't seem to exist.
822 =item Can't make list assignment to \%ENV on this system
824 (F) List assignment to %ENV is not supported on some systems, notably
827 =item Can't modify %s in %s
829 (F) You aren't allowed to assign to the item indicated, or otherwise try
830 to change it, such as with an auto-increment.
832 =item Can't modify nonexistent substring
834 (P) The internal routine that does assignment to a substr() was handed
837 =item Can't modify non-lvalue subroutine call
839 (F) Subroutines meant to be used in lvalue context should be declared as
840 such, see L<perlsub/"Lvalue subroutines">.
842 =item Can't msgrcv to read-only var
844 (F) The target of a msgrcv must be modifiable to be used as a receive
847 =item Can't "next" outside a loop block
849 (F) A "next" statement was executed to reiterate the current block, but
850 there isn't a current block. Note that an "if" or "else" block doesn't
851 count as a "loopish" block, as doesn't a block given to sort(), map() or
852 grep(). You can usually double the curlies to get the same effect
853 though, because the inner curlies will be considered a block that loops
854 once. See L<perlfunc/next>.
856 =item Can't open %s: %s
858 (S inplace) The implicit opening of a file through use of the C<< <> >>
859 filehandle, either implicitly under the C<-n> or C<-p> command-line
860 switches, or explicitly, failed for the indicated reason. Usually this
861 is because you don't have read permission for a file which you named on
864 =item Can't open bidirectional pipe
866 (W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
867 You can try any of several modules in the Perl library to do this, such
868 as IPC::Open2. Alternately, direct the pipe's output to a file using
869 ">", and then read it in under a different file handle.
871 =item Can't open error file %s as stderr
873 (F) An error peculiar to VMS. Perl does its own command line
874 redirection, and couldn't open the file specified after '2>' or '2>>' on
875 the command line for writing.
877 =item Can't open input file %s as stdin
879 (F) An error peculiar to VMS. Perl does its own command line
880 redirection, and couldn't open the file specified after '<' on the
881 command line for reading.
883 =item Can't open output file %s as stdout
885 (F) An error peculiar to VMS. Perl does its own command line
886 redirection, and couldn't open the file specified after '>' or '>>' on
887 the command line for writing.
889 =item Can't open output pipe (name: %s)
891 (P) An error peculiar to VMS. Perl does its own command line
892 redirection, and couldn't open the pipe into which to send data destined
895 =item Can't open perl script%s: %s
897 (F) The script you specified can't be opened for the indicated reason.
899 =item Can't read CRTL environ
901 (S) A warning peculiar to VMS. Perl tried to read an element of %ENV
902 from the CRTL's internal environment array and discovered the array was
903 missing. You need to figure out where your CRTL misplaced its environ
904 or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
907 =item Can't redefine active sort subroutine %s
909 (F) Perl optimizes the internal handling of sort subroutines and keeps
910 pointers into them. You tried to redefine one such sort subroutine when
911 it was currently active, which is not allowed. If you really want to do
912 this, you should write C<sort { &func } @x> instead of C<sort func @x>.
914 =item Can't "redo" outside a loop block
916 (F) A "redo" statement was executed to restart the current block, but
917 there isn't a current block. Note that an "if" or "else" block doesn't
918 count as a "loopish" block, as doesn't a block given to sort(), map()
919 or grep(). You can usually double the curlies to get the same effect
920 though, because the inner curlies will be considered a block that
921 loops once. See L<perlfunc/redo>.
923 =item Can't remove %s: %s, skipping file
925 (S inplace) You requested an inplace edit without creating a backup
926 file. Perl was unable to remove the original file to replace it with
927 the modified file. The file was left unmodified.
929 =item Can't rename %s to %s: %s, skipping file
931 (S inplace) The rename done by the B<-i> switch failed for some reason,
932 probably because you don't have write permission to the directory.
934 =item Can't reopen input pipe (name: %s) in binary mode
936 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
937 to reopen it to accept binary data. Alas, it failed.
939 =item Can't resolve method `%s' overloading `%s' in package `%s'
941 (F|P) Error resolving overloading specified by a method name (as opposed
942 to a subroutine reference): no such method callable via the package. If
943 method name is C<???>, this is an internal error.
945 =item Can't reswap uid and euid
947 (P) The setreuid() call failed for some reason in the setuid emulator of
950 =item Can't return %s from lvalue subroutine
952 (F) Perl detected an attempt to return illegal lvalues (such as
953 temporary or readonly values) from a subroutine used as an lvalue. This
956 =item Can't return %s to lvalue scalar context
958 (F) You tried to return a complete array or hash from an lvalue subroutine,
959 but you called the subroutine in a way that made Perl think you meant
960 to return only one value. You probably meant to write parentheses around
961 the call to the subroutine, which tell Perl that the call should be in
964 =item Can't return outside a subroutine
966 (F) The return statement was executed in mainline code, that is, where
967 there was no subroutine call to return out of. See L<perlsub>.
969 =item Can't stat script "%s"
971 (P) For some reason you can't fstat() the script even though you have it
972 open already. Bizarre.
974 =item Can't swap uid and euid
976 (P) The setreuid() call failed for some reason in the setuid emulator of
979 =item Can't take log of %g
981 (F) For ordinary real numbers, you can't take the logarithm of a
982 negative number or zero. There's a Math::Complex package that comes
983 standard with Perl, though, if you really want to do that for the
986 =item Can't take sqrt of %g
988 (F) For ordinary real numbers, you can't take the square root of a
989 negative number. There's a Math::Complex package that comes standard
990 with Perl, though, if you really want to do that.
992 =item Can't undef active subroutine
994 (F) You can't undefine a routine that's currently running. You can,
995 however, redefine it while it's running, and you can even undef the
996 redefined subroutine while the old routine is running. Go figure.
1000 (F) You tried to unshift an "unreal" array that can't be unshifted, such
1001 as the main Perl stack.
1003 =item Can't upgrade that kind of scalar
1005 (P) The internal sv_upgrade routine adds "members" to an SV, making it
1006 into a more specialized kind of SV. The top several SV types are so
1007 specialized, however, that they cannot be interconverted. This message
1008 indicates that such a conversion was attempted.
1010 =item Can't upgrade to undef
1012 (P) The undefined SV is the bottom of the totem pole, in the scheme of
1013 upgradability. Upgrading to undef indicates an error in the code
1016 =item Can't use an undefined value as %s reference
1018 (F) A value used as either a hard reference or a symbolic reference must
1019 be a defined value. This helps to delurk some insidious errors.
1021 =item Can't use anonymous symbol table for method lookup
1023 (P) The internal routine that does method lookup was handed a symbol
1024 table that doesn't have a name. Symbol tables can become anonymous
1025 for example by undefining stashes: C<undef %Some::Package::>.
1027 =item Can't use bareword ("%s") as %s ref while "strict refs" in use
1029 (F) Only hard references are allowed by "strict refs". Symbolic
1030 references are disallowed. See L<perlref>.
1032 =item Can't use %! because Errno.pm is not available
1034 (F) The first time the %! hash is used, perl automatically loads the
1035 Errno.pm module. The Errno module is expected to tie the %! hash to
1036 provide symbolic names for C<$!> errno values.
1038 =item Can't use %s for loop variable
1040 (F) Only a simple scalar variable may be used as a loop variable on a
1043 =item Can't use global %s in "my"
1045 (F) You tried to declare a magical variable as a lexical variable. This
1046 is not allowed, because the magic can be tied to only one location
1047 (namely the global variable) and it would be incredibly confusing to
1048 have variables in your program that looked like magical variables but
1051 =item Can't use "my %s" in sort comparison
1053 (F) The global variables $a and $b are reserved for sort comparisons.
1054 You mentioned $a or $b in the same line as the <=> or cmp operator,
1055 and the variable had earlier been declared as a lexical variable.
1056 Either qualify the sort variable with the package name, or rename the
1059 =item Can't use %s ref as %s ref
1061 (F) You've mixed up your reference types. You have to dereference a
1062 reference of the type needed. You can use the ref() function to
1063 test the type of the reference, if need be.
1065 =item Can't use string ("%s") as %s ref while "strict refs" in use
1067 (F) Only hard references are allowed by "strict refs". Symbolic
1068 references are disallowed. See L<perlref>.
1070 =item Can't use subscript on %s
1072 (F) The compiler tried to interpret a bracketed expression as a
1073 subscript. But to the left of the brackets was an expression that
1074 didn't look like an array reference, or anything else subscriptable.
1076 =item Can't use \%c to mean $%c in expression
1078 (W syntax) In an ordinary expression, backslash is a unary operator that
1079 creates a reference to its argument. The use of backslash to indicate a
1080 backreference to a matched substring is valid only as part of a regular
1081 expression pattern. Trying to do this in ordinary Perl code produces a
1082 value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1085 =item Can't weaken a nonreference
1087 (F) You attempted to weaken something that was not a reference. Only
1088 references can be weakened.
1090 =item Can't x= to read-only value
1092 (F) You tried to repeat a constant value (often the undefined value)
1093 with an assignment operator, which implies modifying the value itself.
1094 Perhaps you need to copy the value to a temporary, and repeat that.
1096 =item Character in "C" format wrapped
1102 where $x is either less than 0 or more than 255; the C<"C"> format is
1103 only for encoding native operating system characters (ASCII, EBCDIC,
1104 and so on) and not for Unicode characters, so Perl behaved as if you meant
1108 If you actually want to pack Unicode codepoints, use the C<"U"> format
1111 =item Character in "c" format wrapped
1117 where $x is either less than -128 or more than 127; the C<"c"> format
1118 is only for encoding native operating system characters (ASCII, EBCDIC,
1119 and so on) and not for Unicode characters, so Perl behaved as if you meant
1121 pack("c", $x & 255);
1123 If you actually want to pack Unicode codepoints, use the C<"U"> format
1126 =item close() on unopened filehandle %s
1128 (W unopened) You tried to close a filehandle that was never opened.
1130 =item %s: Command not found
1132 (A) You've accidentally run your script through B<csh> instead of Perl.
1133 Check the #! line, or manually feed your script into Perl yourself.
1135 =item Compilation failed in require
1137 (F) Perl could not compile a file specified in a C<require> statement.
1138 Perl uses this generic message when none of the errors that it
1139 encountered were severe enough to halt compilation immediately.
1141 =item Complex regular subexpression recursion limit (%d) exceeded
1143 (W regexp) The regular expression engine uses recursion in complex
1144 situations where back-tracking is required. Recursion depth is limited
1145 to 32766, or perhaps less in architectures where the stack cannot grow
1146 arbitrarily. ("Simple" and "medium" situations are handled without
1147 recursion and are not subject to a limit.) Try shortening the string
1148 under examination; looping in Perl code (e.g. with C<while>) rather than
1149 in the regular expression engine; or rewriting the regular expression so
1150 that it is simpler or backtracks less. (See L<perlfaq2> for information
1151 on I<Mastering Regular Expressions>.)
1153 =item connect() on closed socket %s
1155 (W closed) You tried to do a connect on a closed socket. Did you forget
1156 to check the return value of your socket() call? See
1157 L<perlfunc/connect>.
1159 =item Constant(%s)%s: %s
1161 (F) The parser found inconsistencies either while attempting to define
1162 an overloaded constant, or when trying to find the character name
1163 specified in the C<\N{...}> escape. Perhaps you forgot to load the
1164 corresponding C<overload> or C<charnames> pragma? See L<charnames> and
1167 =item Constant is not %s reference
1169 (F) A constant value (perhaps declared using the C<use constant> pragma)
1170 is being dereferenced, but it amounts to the wrong type of reference.
1171 The message indicates the type of reference that was expected. This
1172 usually indicates a syntax error in dereferencing the constant value.
1173 See L<perlsub/"Constant Functions"> and L<constant>.
1175 =item Constant subroutine %s redefined
1177 (S|W redefine) You redefined a subroutine which had previously been
1178 eligible for inlining. See L<perlsub/"Constant Functions"> for
1179 commentary and workarounds.
1181 =item Constant subroutine %s undefined
1183 (W misc) You undefined a subroutine which had previously been eligible
1184 for inlining. See L<perlsub/"Constant Functions"> for commentary and
1187 =item Copy method did not return a reference
1189 (F) The method which overloads "=" is buggy. See
1190 L<overload/Copy Constructor>.
1192 =item CORE::%s is not a keyword
1194 (F) The CORE:: namespace is reserved for Perl keywords.
1196 =item corrupted regexp pointers
1198 (P) The regular expression engine got confused by what the regular
1199 expression compiler gave it.
1201 =item corrupted regexp program
1203 (P) The regular expression engine got passed a regexp program without a
1206 =item Corrupt malloc ptr 0x%lx at 0x%lx
1208 (P) The malloc package that comes with Perl had an internal failure.
1210 =item C<-p> destination: %s
1212 (F) An error occurred during the implicit output invoked by the C<-p>
1213 command-line switch. (This output goes to STDOUT unless you've
1214 redirected it with select().)
1216 =item C<-T> and C<-B> not implemented on filehandles
1218 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
1219 know about your kind of stdio. You'll have to use a filename instead.
1221 =item Deep recursion on subroutine "%s"
1223 (W recursion) This subroutine has called itself (directly or indirectly)
1224 100 times more than it has returned. This probably indicates an
1225 infinite recursion, unless you're writing strange benchmark programs, in
1226 which case it indicates something else.
1228 =item defined(@array) is deprecated
1230 (D deprecated) defined() is not usually useful on arrays because it
1231 checks for an undefined I<scalar> value. If you want to see if the
1232 array is empty, just use C<if (@array) { # not empty }> for example.
1234 =item defined(%hash) is deprecated
1236 (D deprecated) defined() is not usually useful on hashes because it
1237 checks for an undefined I<scalar> value. If you want to see if the hash
1238 is empty, just use C<if (%hash) { # not empty }> for example.
1240 =item %s defines neither package nor VERSION--version check failed
1242 (F) You said something like "use Module 42" but in the Module file
1243 there are neither package declarations nor a C<$VERSION>.
1245 =item Delimiter for here document is too long
1247 (F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1248 long for Perl to handle. You have to be seriously twisted to write code
1249 that triggers this error.
1251 =item Did not produce a valid header
1255 =item %s did not return a true value
1257 (F) A required (or used) file must return a true value to indicate that
1258 it compiled correctly and ran its initialization code correctly. It's
1259 traditional to end such a file with a "1;", though any true value would
1260 do. See L<perlfunc/require>.
1262 =item (Did you mean &%s instead?)
1264 (W) You probably referred to an imported subroutine &FOO as $FOO or some
1267 =item (Did you mean "local" instead of "our"?)
1269 (W misc) Remember that "our" does not localize the declared global
1270 variable. You have declared it again in the same lexical scope, which
1273 =item (Did you mean $ or @ instead of %?)
1275 (W) You probably said %hash{$key} when you meant $hash{$key} or
1276 @hash{@keys}. On the other hand, maybe you just meant %hash and got
1281 (F) You passed die() an empty string (the equivalent of C<die "">) or
1282 you called it with no args and both C<$@> and C<$_> were empty.
1284 =item Document contains no data
1288 =item %s does not define %s::VERSION--version check failed
1290 (F) You said something like "use Module 42" but the Module did not
1291 define a C<$VERSION.>
1293 =item Don't know how to handle magic of type '%s'
1295 (P) The internal handling of magical variables has been cursed.
1297 =item do_study: out of memory
1299 (P) This should have been caught by safemalloc() instead.
1301 =item (Do you need to predeclare %s?)
1303 (S) This is an educated guess made in conjunction with the message "%s
1304 found where operator expected". It often means a subroutine or module
1305 name is being referenced that hasn't been declared yet. This may be
1306 because of ordering problems in your file, or because of a missing
1307 "sub", "package", "require", or "use" statement. If you're referencing
1308 something that isn't defined yet, you don't actually have to define the
1309 subroutine or package before the current location. You can use an empty
1310 "sub foo;" or "package FOO;" to enter a "forward" declaration.
1312 =item dump() better written as CORE::dump()
1314 (W misc) You used the obsolescent C<dump()> built-in function, without fully
1315 qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1317 =item Duplicate free() ignored
1319 (S malloc) An internal routine called free() on something that had
1322 =item elseif should be elsif
1324 (S) There is no keyword "elseif" in Perl because Larry thinks it's ugly.
1325 Your code will be interpreted as an attempt to call a method named
1326 "elseif" for the class returned by the following block. This is
1327 unlikely to be what you want.
1331 (F) Empty C<\p{}> or C<\P{}>.
1333 =item entering effective %s failed
1335 (F) While under the C<use filetest> pragma, switching the real and
1336 effective uids or gids failed.
1338 =item Error converting file specification %s
1340 (F) An error peculiar to VMS. Because Perl may have to deal with file
1341 specifications in either VMS or Unix syntax, it converts them to a
1342 single form when it must operate on them directly. Either you've passed
1343 an invalid file specification to Perl, or you've found a case the
1344 conversion routines don't handle. Drat.
1346 =item %s: Eval-group in insecure regular expression
1348 (F) Perl detected tainted data when trying to compile a regular
1349 expression that contains the C<(?{ ... })> zero-width assertion, which
1350 is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
1352 =item %s: Eval-group not allowed at run time
1354 (F) Perl tried to compile a regular expression containing the
1355 C<(?{ ... })> zero-width assertion at run time, as it would when the
1356 pattern contains interpolated values. Since that is a security risk, it
1357 is not allowed. If you insist, you may still do this by explicitly
1358 building the pattern from an interpolated string at run time and using
1359 that in an eval(). See L<perlre/(?{ code })>.
1361 =item %s: Eval-group not allowed, use re 'eval'
1363 (F) A regular expression contained the C<(?{ ... })> zero-width
1364 assertion, but that construct is only allowed when the C<use re 'eval'>
1365 pragma is in effect. See L<perlre/(?{ code })>.
1367 =item Excessively long <> operator
1369 (F) The contents of a <> operator may not exceed the maximum size of a
1370 Perl identifier. If you're just trying to glob a long list of
1371 filenames, try using the glob() operator, or put the filenames into a
1372 variable and glob that.
1374 =item exec? I'm not *that* kind of operating system
1376 (F) The C<exec> function is not implemented in MacPerl. See L<perlport>.
1378 =item Execution of %s aborted due to compilation errors
1380 (F) The final summary message when a Perl compilation fails.
1382 =item Exiting eval via %s
1384 (W exiting) You are exiting an eval by unconventional means, such as a
1385 goto, or a loop control statement.
1387 =item Exiting format via %s
1389 (W exiting) You are exiting an eval by unconventional means, such as a
1390 goto, or a loop control statement.
1392 =item Exiting pseudo-block via %s
1394 (W exiting) You are exiting a rather special block construct (like a
1395 sort block or subroutine) by unconventional means, such as a goto, or a
1396 loop control statement. See L<perlfunc/sort>.
1398 =item Exiting subroutine via %s
1400 (W exiting) You are exiting a subroutine by unconventional means, such
1401 as a goto, or a loop control statement.
1403 =item Exiting substitution via %s
1405 (W exiting) You are exiting a substitution by unconventional means, such
1406 as a return, a goto, or a loop control statement.
1408 =item Explicit blessing to '' (assuming package main)
1410 (W misc) You are blessing a reference to a zero length string. This has
1411 the effect of blessing the reference into the package main. This is
1412 usually not what you want. Consider providing a default target package,
1413 e.g. bless($ref, $p || 'MyPackage');
1415 =item %s: Expression syntax
1417 (A) You've accidentally run your script through B<csh> instead of Perl.
1418 Check the #! line, or manually feed your script into Perl yourself.
1420 =item %s failed--call queue aborted
1422 (F) An untrapped exception was raised while executing a CHECK, INIT, or
1423 END subroutine. Processing of the remainder of the queue of such
1424 routines has been prematurely ended.
1426 =item False [] range "%s" in regex; marked by <-- HERE in m/%s/
1428 (W regexp) A character class range must start and end at a literal
1429 character, not another character class like C<\d> or C<[:alpha:]>. The "-"
1430 in your false range is interpreted as a literal "-". Consider quoting the
1431 "-", "\-". The <-- HERE shows in the regular expression about where the
1432 problem was discovered. See L<perlre>.
1434 =item Fatal VMS error at %s, line %d
1436 (P) An error peculiar to VMS. Something untoward happened in a VMS
1437 system service or RTL routine; Perl's exit status should provide more
1438 details. The filename in "at %s" and the line number in "line %d" tell
1439 you which section of the Perl source code is distressed.
1441 =item fcntl is not implemented
1443 (F) Your machine apparently doesn't implement fcntl(). What is this, a
1444 PDP-11 or something?
1446 =item Filehandle %s opened only for input
1448 (W io) You tried to write on a read-only filehandle. If you intended it
1449 to be a read-write filehandle, you needed to open it with "+<" or "+>"
1450 or "+>>" instead of with "<" or nothing. If you intended only to write
1451 the file, use ">" or ">>". See L<perlfunc/open>.
1453 =item Filehandle %s opened only for output
1455 (W io) You tried to read from a filehandle opened only for writing. If
1456 you intended it to be a read/write filehandle, you needed to open it
1457 with "+<" or "+>" or "+>>" instead of with "<" or nothing. If you
1458 intended only to read from the file, use "<". See L<perlfunc/open>.
1460 =item Final $ should be \$ or $name
1462 (F) You must now decide whether the final $ in a string was meant to be
1463 a literal dollar sign, or was meant to introduce a variable name that
1464 happens to be missing. So you have to put either the backslash or the
1467 =item Final @ should be \@ or @name
1469 (F) You must now decide whether the final @ in a string was meant to be
1470 a literal "at" sign, or was meant to introduce a variable name that
1471 happens to be missing. So you have to put either the backslash or the
1474 =item flock() on closed filehandle %s
1476 (W closed) The filehandle you're attempting to flock() got itself closed
1477 some time before now. Check your control flow. flock() operates on
1478 filehandles. Are you attempting to call flock() on a dirhandle by the
1481 =item Quantifier follows nothing in regex;
1483 marked by <-- HERE in m/%s/
1485 (F) You started a regular expression with a quantifier. Backslash it if you
1486 meant it literally. The <-- HERE shows in the regular expression about
1487 where the problem was discovered. See L<perlre>.
1489 =item Format not terminated
1491 (F) A format must be terminated by a line with a solitary dot. Perl got
1492 to the end of your file without finding such a line.
1494 =item Format %s redefined
1496 (W redefine) You redefined a format. To suppress this warning, say
1499 no warnings 'redefine';
1500 eval "format NAME =...";
1503 =item Found = in conditional, should be ==
1513 (or something like that).
1515 =item %s found where operator expected
1517 (S) The Perl lexer knows whether to expect a term or an operator. If it
1518 sees what it knows to be a term when it was expecting to see an
1519 operator, it gives you this warning. Usually it indicates that an
1520 operator or delimiter was omitted, such as a semicolon.
1522 =item gdbm store returned %d, errno %d, key "%s"
1524 (S) A warning from the GDBM_File extension that a store failed.
1526 =item gethostent not implemented
1528 (F) Your C library apparently doesn't implement gethostent(), probably
1529 because if it did, it'd feel morally obligated to return every hostname
1532 =item get%sname() on closed socket %s
1534 (W closed) You tried to get a socket or peer socket name on a closed
1535 socket. Did you forget to check the return value of your socket() call?
1537 =item getpwnam returned invalid UIC %#o for user "%s"
1539 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1540 C<getpwnam> operator returned an invalid UIC.
1542 =item getsockopt() on closed socket %s
1544 (W closed) You tried to get a socket option on a closed socket. Did you
1545 forget to check the return value of your socket() call? See
1546 L<perlfunc/getsockopt>.
1548 =item Global symbol "%s" requires explicit package name
1550 (F) You've said "use strict vars", which indicates that all variables
1551 must either be lexically scoped (using "my"), declared beforehand using
1552 "our", or explicitly qualified to say which package the global variable
1555 =item glob failed (%s)
1557 (W glob) Something went wrong with the external program(s) used for
1558 C<glob> and C<< <*.c> >>. Usually, this means that you supplied a
1559 C<glob> pattern that caused the external program to fail and exit with a
1560 nonzero status. If the message indicates that the abnormal exit
1561 resulted in a coredump, this may also mean that your csh (C shell) is
1562 broken. If so, you should change all of the csh-related variables in
1563 config.sh: If you have tcsh, make the variables refer to it as if it
1564 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1565 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1566 think csh is missing. In either case, after editing config.sh, run
1567 C<./Configure -S> and rebuild Perl.
1569 =item Glob not terminated
1571 (F) The lexer saw a left angle bracket in a place where it was expecting
1572 a term, so it's looking for the corresponding right angle bracket, and
1573 not finding it. Chances are you left some needed parentheses out
1574 earlier in the line, and you really meant a "less than".
1576 =item Got an error from DosAllocMem
1578 (P) An error peculiar to OS/2. Most probably you're using an obsolete
1579 version of Perl, and this should not happen anyway.
1581 =item goto must have label
1583 (F) Unlike with "next" or "last", you're not allowed to goto an
1584 unspecified destination. See L<perlfunc/goto>.
1586 =item %s-group starts with a count
1588 (F) In pack/unpack a ()-group started with a count. A count is
1589 supposed to follow something: a template character or a ()-group.
1591 =item %s had compilation errors
1593 (F) The final summary message when a C<perl -c> fails.
1595 =item Had to create %s unexpectedly
1597 (S internal) A routine asked for a symbol from a symbol table that ought
1598 to have existed already, but for some reason it didn't, and had to be
1599 created on an emergency basis to prevent a core dump.
1601 =item Hash %%s missing the % in argument %d of %s()
1603 (D deprecated) Really old Perl let you omit the % on hash names in some
1604 spots. This is now heavily deprecated.
1606 =item %s has too many errors
1608 (F) The parser has given up trying to parse the program after 10 errors.
1609 Further error messages would likely be uninformative.
1611 =item Hexadecimal number > 0xffffffff non-portable
1613 (W portable) The hexadecimal number you specified is larger than 2**32-1
1614 (4294967295) and therefore non-portable between systems. See
1615 L<perlport> for more on portability concerns.
1617 =item Identifier too long
1619 (F) Perl limits identifiers (names for variables, functions, etc.) to
1620 about 250 characters for simple names, and somewhat more for compound
1621 names (like C<$A::B>). You've exceeded Perl's limits. Future versions
1622 of Perl are likely to eliminate these arbitrary limitations.
1624 =item Illegal binary digit %s
1626 (F) You used a digit other than 0 or 1 in a binary number.
1628 =item Illegal binary digit %s ignored
1630 (W digit) You may have tried to use a digit other than 0 or 1 in a
1631 binary number. Interpretation of the binary number stopped before the
1634 =item Illegal character %s (carriage return)
1636 (F) Perl normally treats carriage returns in the program text as it
1637 would any other whitespace, which means you should never see this error
1638 when Perl was built using standard options. For some reason, your
1639 version of Perl appears to have been built without this support. Talk
1640 to your Perl administrator.
1642 =item Illegal character in prototype for %s : %s
1644 (W syntax) An illegal character was found in a prototype declaration. Legal
1645 characters in prototypes are $, @, %, *, ;, [, ], &, and \.
1647 =item Illegal division by zero
1649 (F) You tried to divide a number by 0. Either something was wrong in
1650 your logic, or you need to put a conditional in to guard against
1653 =item Illegal hexadecimal digit %s ignored
1655 (W digit) You may have tried to use a character other than 0 - 9 or
1656 A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
1657 number stopped before the illegal character.
1659 =item Illegal modulus zero
1661 (F) You tried to divide a number by 0 to get the remainder. Most
1662 numbers don't take to this kindly.
1664 =item Illegal number of bits in vec
1666 (F) The number of bits in vec() (the third argument) must be a power of
1667 two from 1 to 32 (or 64, if your platform supports that).
1669 =item Illegal octal digit %s
1671 (F) You used an 8 or 9 in an octal number.
1673 =item Illegal octal digit %s ignored
1675 (W digit) You may have tried to use an 8 or 9 in an octal number.
1676 Interpretation of the octal number stopped before the 8 or 9.
1678 =item Illegal switch in PERL5OPT: %s
1680 (X) The PERL5OPT environment variable may only be used to set the
1681 following switches: B<-[DIMUdmtw]>.
1683 =item Ill-formed CRTL environ value "%s"
1685 (W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
1686 internal environ array, and encountered an element without the C<=>
1687 delimiter used to separate keys from values. The element is ignored.
1689 =item Ill-formed message in prime_env_iter: |%s|
1691 (W internal) A warning peculiar to VMS. Perl tried to read a logical
1692 name or CLI symbol definition when preparing to iterate over %ENV, and
1693 didn't see the expected delimiter between key and value, so the line was
1696 =item (in cleanup) %s
1698 (W misc) This prefix usually indicates that a DESTROY() method raised
1699 the indicated exception. Since destructors are usually called by the
1700 system at arbitrary points during execution, and often a vast number of
1701 times, the warning is issued only once for any number of failures that
1702 would otherwise result in the same message being repeated.
1704 Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
1705 also result in this warning. See L<perlcall/G_KEEPERR>.
1707 =item In EBCDIC the v-string components cannot exceed 2147483647
1709 (F) An error peculiar to EBCDIC. Internally, v-strings are stored as
1710 Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
1711 encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
1713 =item Insecure dependency in %s
1715 (F) You tried to do something that the tainting mechanism didn't like.
1716 The tainting mechanism is turned on when you're running setuid or
1717 setgid, or when you specify B<-T> to turn it on explicitly. The
1718 tainting mechanism labels all data that's derived directly or indirectly
1719 from the user, who is considered to be unworthy of your trust. If any
1720 such data is used in a "dangerous" operation, you get this error. See
1721 L<perlsec> for more information.
1723 =item Insecure directory in %s
1725 (F) You can't use system(), exec(), or a piped open in a setuid or
1726 setgid script if C<$ENV{PATH}> contains a directory that is writable by
1727 the world. See L<perlsec>.
1729 =item Insecure $ENV{%s} while running %s
1731 (F) You can't use system(), exec(), or a piped open in a setuid or
1732 setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
1733 C<$ENV{ENV}> or C<$ENV{BASH_ENV}> are derived from data supplied (or
1734 potentially supplied) by the user. The script must set the path to a
1735 known value, using trustworthy data. See L<perlsec>.
1737 =item Integer overflow in %s number
1739 (W overflow) The hexadecimal, octal or binary number you have specified
1740 either as a literal or as an argument to hex() or oct() is too big for
1741 your architecture, and has been converted to a floating point number.
1742 On a 32-bit architecture the largest hexadecimal, octal or binary number
1743 representable without overflow is 0xFFFFFFFF, 037777777777, or
1744 0b11111111111111111111111111111111 respectively. Note that Perl
1745 transparently promotes all numbers to a floating point representation
1746 internally--subject to loss of precision errors in subsequent
1749 =item Internal disaster in regex; marked by <-- HERE in m/%s/
1751 (P) Something went badly wrong in the regular expression parser.
1752 The <-- HERE shows in the regular expression about where the problem was
1755 =item Internal inconsistency in tracking vforks
1757 (S) A warning peculiar to VMS. Perl keeps track of the number of times
1758 you've called C<fork> and C<exec>, to determine whether the current call
1759 to C<exec> should affect the current script or a subprocess (see
1760 L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
1761 Perl is making a guess and treating this C<exec> as a request to
1762 terminate the Perl script and execute the specified command.
1764 =item Internal urp in regex; marked by <-- HERE in m/%s/
1766 (P) Something went badly awry in the regular expression parser. The
1767 <-- HERE shows in the regular expression about where the problem was
1770 =item %s (...) interpreted as function
1772 (W syntax) You've run afoul of the rule that says that any list operator
1773 followed by parentheses turns into a function, with all the list
1774 operators arguments found inside the parentheses. See
1775 L<perlop/Terms and List Operators (Leftward)>.
1777 =item Invalid %s attribute: %s
1779 The indicated attribute for a subroutine or variable was not recognized
1780 by Perl or by a user-supplied handler. See L<attributes>.
1782 =item Invalid %s attributes: %s
1784 The indicated attributes for a subroutine or variable were not
1785 recognized by Perl or by a user-supplied handler. See L<attributes>.
1787 =item Invalid conversion in %s: "%s"
1789 (W printf) Perl does not understand the given format conversion. See
1790 L<perlfunc/sprintf>.
1792 =item Invalid [] range "%s" in regex; marked by <-- HERE in m/%s/
1794 (F) The range specified in a character class had a minimum character
1795 greater than the maximum character. One possibility is that you forgot the
1796 C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
1797 up to C<ff>. The <-- HERE shows in the regular expression about where the
1798 problem was discovered. See L<perlre>.
1800 =item Invalid [] range "%s" in transliteration operator
1802 (F) The range specified in the tr/// or y/// operator had a minimum
1803 character greater than the maximum character. See L<perlop>.
1805 =item Invalid separator character %s in attribute list
1807 (F) Something other than a colon or whitespace was seen between the
1808 elements of an attribute list. If the previous attribute had a
1809 parenthesised parameter list, perhaps that list was terminated too soon.
1812 =item Invalid type in pack: '%s'
1814 (F) The given character is not a valid pack type. See L<perlfunc/pack>.
1815 (W pack) The given character is not a valid pack type but used to be
1818 =item Invalid type in unpack: '%s'
1820 (F) The given character is not a valid unpack type. See
1822 (W unpack) The given character is not a valid unpack type but used to be
1825 =item ioctl is not implemented
1827 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1828 strange for a machine that supports C.
1830 =item ioctl() on unopened %s
1832 (W unopened) You tried ioctl() on a filehandle that was never opened.
1833 Check you control flow and number of arguments.
1835 =item IO::Socket::atmark not implemented on this architecture
1837 (F) Your machine doesn't implement the sockatmark() functionality,
1838 neither as a system call or an ioctl call (SIOCATMARK).
1840 =item `%s' is not a code reference
1842 (W overload) The second (fourth, sixth, ...) argument of overload::constant
1843 needs to be a code reference. Either an anonymous subroutine, or a reference
1846 =item `%s' is not an overloadable type
1848 (W overload) You tried to overload a constant type the overload package is
1851 =item junk on end of regexp
1853 (P) The regular expression parser is confused.
1855 =item Label not found for "last %s"
1857 (F) You named a loop to break out of, but you're not currently in a loop
1858 of that name, not even if you count where you were called from. See
1861 =item Label not found for "next %s"
1863 (F) You named a loop to continue, but you're not currently in a loop of
1864 that name, not even if you count where you were called from. See
1867 =item Label not found for "redo %s"
1869 (F) You named a loop to restart, but you're not currently in a loop of
1870 that name, not even if you count where you were called from. See
1873 =item leaving effective %s failed
1875 (F) While under the C<use filetest> pragma, switching the real and
1876 effective uids or gids failed.
1878 =item listen() on closed socket %s
1880 (W closed) You tried to do a listen on a closed socket. Did you forget
1881 to check the return value of your socket() call? See
1884 =item lstat() on filehandle %s
1886 (W io) You tried to do an lstat on a filehandle. What did you mean
1887 by that? lstat() makes sense only on filenames. (Perl did a fstat()
1888 instead on the filehandle.)
1890 =item Lvalue subs returning %s not implemented yet
1892 (F) Due to limitations in the current implementation, array and hash
1893 values cannot be returned in subroutines used in lvalue context. See
1894 L<perlsub/"Lvalue subroutines">.
1896 =item Lookbehind longer than %d not implemented in regex;
1898 marked by <-- HERE in m/%s/
1900 (F) There is currently a limit on the length of string which lookbehind can
1901 handle. This restriction may be eased in a future release. The <-- HERE
1902 shows in the regular expression about where the problem was discovered.
1904 =item Malformed PERLLIB_PREFIX
1906 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
1913 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
1914 a builtin library search path, prefix2 is substituted. The error may
1915 appear if components are not found, or are too long. See
1916 "PERLLIB_PREFIX" in L<perlos2>.
1918 =item Malformed prototype for %s: %s
1920 (F) You tried to use a function with a malformed prototype. The
1921 syntax of function prototypes is given a brief compile-time check for
1922 obvious errors like invalid characters. A more rigorous check is run
1923 when the function is called.
1925 =item Malformed UTF-8 character (%s)
1927 Perl detected something that didn't comply with UTF-8 encoding rules.
1929 One possible cause is that you read in data that you thought to be in
1930 UTF-8 but it wasn't (it was for example legacy 8-bit data). Another
1931 possibility is careless use of utf8::upgrade().
1933 =item Malformed UTF-16 surrogate
1935 Perl thought it was reading UTF-16 encoded character data but while
1936 doing it Perl met a malformed Unicode surrogate.
1938 =item %s matches null string many times in regex;
1940 marked by <-- HERE in m/%s/
1942 (W regexp) The pattern you've specified would be an infinite loop if the
1943 regular expression engine didn't specifically check for that. The <-- HERE
1944 shows in the regular expression about where the problem was discovered.
1947 =item "%s" may clash with future reserved word
1949 (W) This warning may be due to running a perl5 script through a perl4
1950 interpreter, especially if the word that is being warned about is
1953 =item % may only be used in unpack
1955 (F) You can't pack a string by supplying a checksum, because the
1956 checksumming process loses information, and you can't go the other way.
1957 See L<perlfunc/unpack>.
1959 =item Method for operation %s not found in package %s during blessing
1961 (F) An attempt was made to specify an entry in an overloading table that
1962 doesn't resolve to a valid subroutine. See L<overload>.
1964 =item Method %s not permitted
1968 =item Might be a runaway multi-line %s string starting on line %d
1970 (S) An advisory indicating that the previous error may have been caused
1971 by a missing delimiter on a string or pattern, because it eventually
1972 ended earlier on the current line.
1974 =item Misplaced _ in number
1976 (W syntax) An underscore (underbar) in a numeric constant did not
1977 separate two digits.
1979 =item Missing %sbrace%s on \N{}
1981 (F) Wrong syntax of character name literal C<\N{charname}> within
1982 double-quotish context.
1984 =item Missing comma after first argument to %s function
1986 (F) While certain functions allow you to specify a filehandle or an
1987 "indirect object" before the argument list, this ain't one of them.
1989 =item Missing command in piped open
1991 (W pipe) You used the C<open(FH, "| command")> or
1992 C<open(FH, "command |")> construction, but the command was missing or
1995 =item Missing name in "my sub"
1997 (F) The reserved syntax for lexically scoped subroutines requires that
1998 they have a name with which they can be found.
2000 =item Missing $ on loop variable
2002 (F) Apparently you've been programming in B<csh> too much. Variables
2003 are always mentioned with the $ in Perl, unlike in the shells, where it
2004 can vary from one line to the next.
2006 =item (Missing operator before %s?)
2008 (S) This is an educated guess made in conjunction with the message "%s
2009 found where operator expected". Often the missing operator is a comma.
2011 =item Missing right brace on %s
2013 (F) Missing right brace in C<\p{...}> or C<\P{...}>.
2015 =item Missing right curly or square bracket
2017 (F) The lexer counted more opening curly or square brackets than closing
2018 ones. As a general rule, you'll find it's missing near the place you
2021 =item (Missing semicolon on previous line?)
2023 (S) This is an educated guess made in conjunction with the message "%s
2024 found where operator expected". Don't automatically put a semicolon on
2025 the previous line just because you saw this message.
2027 =item Modification of a read-only value attempted
2029 (F) You tried, directly or indirectly, to change the value of a
2030 constant. You didn't, of course, try "2 = 1", because the compiler
2031 catches that. But an easy way to do the same thing is:
2033 sub mod { $_[0] = 1 }
2036 Another way is to assign to a substr() that's off the end of the string.
2038 Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
2039 is aliased to a constant in the look I<LIST>:
2042 foreach my $n ($x, 2) {
2043 $n *= 2; # modifies the $x, but fails on attempt to modify the 2
2046 =item Modification of non-creatable array value attempted, %s
2048 (F) You tried to make an array value spring into existence, and the
2049 subscript was probably negative, even counting from end of the array
2052 =item Modification of non-creatable hash value attempted, %s
2054 (P) You tried to make a hash value spring into existence, and it
2055 couldn't be created for some peculiar reason.
2057 =item Module name must be constant
2059 (F) Only a bare module name is allowed as the first argument to a "use".
2061 =item Module name required with -%c option
2063 (F) The C<-M> or C<-m> options say that Perl should load some module, but
2064 you omitted the name of the module. Consult L<perlrun> for full details
2065 about C<-M> and C<-m>.
2067 =item More than one argument to open
2069 (F) The C<open> function has been asked to open multiple files. This
2070 can happen if you are trying to open a pipe to a command that takes a
2071 list of arguments, but have forgotten to specify a piped open mode.
2072 See L<perlfunc/open> for details.
2074 =item msg%s not implemented
2076 (F) You don't have System V message IPC on your system.
2078 =item Multidimensional syntax %s not supported
2080 (W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
2081 They're written like C<$foo[1][2][3]>, as in C.
2083 =item / must be followed by a*, A* or Z*
2085 (F) You had a pack template indicating a counted-length string,
2086 Currently the only things that can have their length counted are a*, A*
2087 or Z*. See L<perlfunc/pack>.
2089 =item / must be followed by a, A or Z
2091 (F) You had an unpack template indicating a counted-length string, which
2092 must be followed by one of the letters a, A or Z to indicate what sort
2093 of string is to be unpacked. See L<perlfunc/pack>.
2095 =item / must follow a numeric type
2097 (F) You had an unpack template that contained a '#', but this did not
2098 follow some numeric unpack specification. See L<perlfunc/pack>.
2100 =item "my sub" not yet implemented
2102 (F) Lexically scoped subroutines are not yet implemented. Don't try
2105 =item "my" variable %s can't be in a package
2107 (F) Lexically scoped variables aren't in a package, so it doesn't make
2108 sense to try to declare one with a package qualifier on the front. Use
2109 local() if you want to localize a package variable.
2111 =item Name "%s::%s" used only once: possible typo
2113 (W once) Typographical errors often show up as unique variable names.
2114 If you had a good reason for having a unique name, then just mention it
2115 again somehow to suppress the message. The C<our> declaration is
2116 provided for this purpose.
2118 =item Negative length
2120 (F) You tried to do a read/write/send/recv operation with a buffer
2121 length that is less than 0. This is difficult to imagine.
2123 =item Negative offset to vec in lvalue context
2125 (F) When C<vec> is called in an lvalue context, the second argument must be
2126 greater than or equal to zero.
2128 =item Nested quantifiers in regex; marked by <-- HERE in m/%s/
2130 (F) You can't quantify a quantifier without intervening parentheses. So
2131 things like ** or +* or ?* are illegal. The <-- HERE shows in the regular
2132 expression about where the problem was discovered.
2134 Note that the minimal matching quantifiers, C<*?>, C<+?>, and
2135 C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
2137 =item %s never introduced
2139 (S internal) The symbol in question was declared but somehow went out of
2140 scope before it could possibly have been used.
2142 =item No %s allowed while running setuid
2144 (F) Certain operations are deemed to be too insecure for a setuid or
2145 setgid script to even be allowed to attempt. Generally speaking there
2146 will be another way to do what you want that is, if not secure, at least
2147 securable. See L<perlsec>.
2149 =item No B<-e> allowed in setuid scripts
2151 (F) A setuid script can't be specified by the user.
2153 =item No comma allowed after %s
2155 (F) A list operator that has a filehandle or "indirect object" is not
2156 allowed to have a comma between that and the following arguments.
2157 Otherwise it'd be just another one of the arguments.
2159 One possible cause for this is that you expected to have imported a
2160 constant to your name space with B<use> or B<import> while no such
2161 importing took place, it may for example be that your operating system
2162 does not support that particular constant. Hopefully you did use an
2163 explicit import list for the constants you expect to see, please see
2164 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
2165 would probably have caught this error earlier it naturally does not
2166 remedy the fact that your operating system still does not support that
2167 constant. Maybe you have a typo in the constants of the symbol import
2168 list of B<use> or B<import> or in the constant name at the line where
2169 this error was triggered?
2171 =item No command into which to pipe on command line
2173 (F) An error peculiar to VMS. Perl handles its own command line
2174 redirection, and found a '|' at the end of the command line, so it
2175 doesn't know where you want to pipe the output from this command.
2177 =item No DB::DB routine defined
2179 (F) The currently executing code was compiled with the B<-d> switch, but
2180 for some reason the perl5db.pl file (or some facsimile thereof) didn't
2181 define a routine to be called at the beginning of each statement. Which
2182 is odd, because the file should have been required automatically, and
2183 should have blown up the require if it didn't parse right.
2185 =item No dbm on this machine
2187 (P) This is counted as an internal error, because every machine should
2188 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
2190 =item No DBsub routine
2192 (F) The currently executing code was compiled with the B<-d> switch,
2193 but for some reason the perl5db.pl file (or some facsimile thereof)
2194 didn't define a DB::sub routine to be called at the beginning of each
2195 ordinary subroutine call.
2197 =item No error file after 2> or 2>> on command line
2199 (F) An error peculiar to VMS. Perl handles its own command line
2200 redirection, and found a '2>' or a '2>>' on the command line, but can't
2201 find the name of the file to which to write data destined for stderr.
2203 =item No input file after < on command line
2205 (F) An error peculiar to VMS. Perl handles its own command line
2206 redirection, and found a '<' on the command line, but can't find the
2207 name of the file from which to read data for stdin.
2211 (F) The setuid emulator requires that scripts have a well-formed #! line
2212 even on machines that don't support the #! construct.
2214 =item "no" not allowed in expression
2216 (F) The "no" keyword is recognized and executed at compile time, and
2217 returns no useful value. See L<perlmod>.
2219 =item No output file after > on command line
2221 (F) An error peculiar to VMS. Perl handles its own command line
2222 redirection, and found a lone '>' at the end of the command line, so it
2223 doesn't know where you wanted to redirect stdout.
2225 =item No output file after > or >> on command line
2227 (F) An error peculiar to VMS. Perl handles its own command line
2228 redirection, and found a '>' or a '>>' on the command line, but can't
2229 find the name of the file to which to write data destined for stdout.
2231 =item No package name allowed for variable %s in "our"
2233 (F) Fully qualified variable names are not allowed in "our"
2234 declarations, because that doesn't make much sense under existing
2235 semantics. Such syntax is reserved for future extensions.
2237 =item No Perl script found in input
2239 (F) You called C<perl -x>, but no line was found in the file beginning
2240 with #! and containing the word "perl".
2242 =item No setregid available
2244 (F) Configure didn't find anything resembling the setregid() call for
2247 =item No setreuid available
2249 (F) Configure didn't find anything resembling the setreuid() call for
2252 =item No space allowed after -%c
2254 (F) The argument to the indicated command line switch must follow
2255 immediately after the switch, without intervening spaces.
2257 =item No %s specified for -%c
2259 (F) The indicated command line switch needs a mandatory argument, but
2260 you haven't specified one.
2262 =item No such class %s
2264 (F) You provided a class qualifier in a "my" or "our" declaration, but
2265 this class doesn't exist at this point in your program.
2267 =item No such pipe open
2269 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
2270 close a pipe which hadn't been opened. This should have been caught
2271 earlier as an attempt to close an unopened filehandle.
2273 =item No such pseudo-hash field "%s"
2275 (F) You tried to access an array as a hash, but the field name used is
2276 not defined. The hash at index 0 should map all valid field names to
2277 array indices for that to work.
2279 =item No such pseudo-hash field "%s" in variable %s of type %s
2281 (F) You tried to access a field of a typed variable where the type does
2282 not know about the field name. The field names are looked up in the
2283 %FIELDS hash in the type package at compile time. The %FIELDS hash is
2284 %usually set up with the 'fields' pragma.
2286 =item No such signal: SIG%s
2288 (W signal) You specified a signal name as a subscript to %SIG that was
2289 not recognized. Say C<kill -l> in your shell to see the valid signal
2290 names on your system.
2292 =item Not a CODE reference
2294 (F) Perl was trying to evaluate a reference to a code value (that is, a
2295 subroutine), but found a reference to something else instead. You can
2296 use the ref() function to find out what kind of ref it really was. See
2299 =item Not a format reference
2301 (F) I'm not sure how you managed to generate a reference to an anonymous
2302 format, but this indicates you did, and that it didn't exist.
2304 =item Not a GLOB reference
2306 (F) Perl was trying to evaluate a reference to a "typeglob" (that is, a
2307 symbol table entry that looks like C<*foo>), but found a reference to
2308 something else instead. You can use the ref() function to find out what
2309 kind of ref it really was. See L<perlref>.
2311 =item Not a HASH reference
2313 (F) Perl was trying to evaluate a reference to a hash value, but found a
2314 reference to something else instead. You can use the ref() function to
2315 find out what kind of ref it really was. See L<perlref>.
2317 =item Not an ARRAY reference
2319 (F) Perl was trying to evaluate a reference to an array value, but found
2320 a reference to something else instead. You can use the ref() function
2321 to find out what kind of ref it really was. See L<perlref>.
2323 =item Not a perl script
2325 (F) The setuid emulator requires that scripts have a well-formed #! line
2326 even on machines that don't support the #! construct. The line must
2329 =item Not a SCALAR reference
2331 (F) Perl was trying to evaluate a reference to a scalar value, but found
2332 a reference to something else instead. You can use the ref() function
2333 to find out what kind of ref it really was. See L<perlref>.
2335 =item Not a subroutine reference
2337 (F) Perl was trying to evaluate a reference to a code value (that is, a
2338 subroutine), but found a reference to something else instead. You can
2339 use the ref() function to find out what kind of ref it really was. See
2342 =item Not a subroutine reference in overload table
2344 (F) An attempt was made to specify an entry in an overloading table that
2345 doesn't somehow point to a valid subroutine. See L<overload>.
2347 =item Not enough arguments for %s
2349 (F) The function requires more arguments than you specified.
2351 =item Not enough format arguments
2353 (W syntax) A format specified more picture fields than the next line
2354 supplied. See L<perlform>.
2358 (A) You've accidentally run your script through the Bourne shell instead
2359 of Perl. Check the #! line, or manually feed your script into Perl
2362 =item %s not allowed in length fields
2364 (F) The count in the (un)pack template may be replaced by C<[TEMPLATE]> only if
2365 C<TEMPLATE> always matches the same amount of packed bytes. Redesign
2368 =item no UTC offset information; assuming local time is UTC
2370 (S) A warning peculiar to VMS. Perl was unable to find the local
2371 timezone offset, so it's assuming that local system time is equivalent
2372 to UTC. If it's not, define the logical name
2373 F<SYS$TIMEZONE_DIFFERENTIAL> to translate to the number of seconds which
2374 need to be added to UTC to get local time.
2376 =item Null filename used
2378 (F) You can't require the null filename, especially because on many
2379 machines that means the current directory! See L<perlfunc/require>.
2381 =item NULL OP IN RUN
2383 (P debugging) Some internal routine called run() with a null opcode
2386 =item Null picture in formline
2388 (F) The first argument to formline must be a valid format picture
2389 specification. It was found to be empty, which probably means you
2390 supplied it an uninitialized value. See L<perlform>.
2394 (P) An attempt was made to realloc NULL.
2396 =item NULL regexp argument
2398 (P) The internal pattern matching routines blew it big time.
2400 =item NULL regexp parameter
2402 (P) The internal pattern matching routines are out of their gourd.
2404 =item Number too long
2406 (F) Perl limits the representation of decimal numbers in programs to
2407 about 250 characters. You've exceeded that length. Future
2408 versions of Perl are likely to eliminate this arbitrary limitation. In
2409 the meantime, try using scientific notation (e.g. "1e6" instead of
2412 =item Octal number in vector unsupported
2414 (F) Numbers with a leading C<0> are not currently allowed in vectors.
2415 The octal number interpretation of such numbers may be supported in a
2418 =item Octal number > 037777777777 non-portable
2420 (W portable) The octal number you specified is larger than 2**32-1
2421 (4294967295) and therefore non-portable between systems. See
2422 L<perlport> for more on portability concerns.
2424 See also L<perlport> for writing portable code.
2426 =item Odd number of arguments for overload::constant
2428 (W overload) The call to overload::constant contained an odd number of
2429 arguments. The arguments should come in pairs.
2431 =item Odd number of elements in anonymous hash
2433 (W misc) You specified an odd number of elements to initialize a hash,
2434 which is odd, because hashes come in key/value pairs.
2436 =item Odd number of elements in hash assignment
2438 (W misc) You specified an odd number of elements to initialize a hash,
2439 which is odd, because hashes come in key/value pairs.
2441 =item Offset outside string
2443 (F) You tried to do a read/write/send/recv operation with an offset
2444 pointing outside the buffer. This is difficult to imagine. The sole
2445 exception to this is that C<sysread()>ing past the buffer will extend
2446 the buffer and zero pad the new area.
2448 =item -%s on unopened filehandle %s
2450 (W unopened) You tried to invoke a file test operator on a filehandle
2451 that isn't open. Check your control flow. See also L<perlfunc/-X>.
2453 =item %s() on unopened %s
2455 (W unopened) An I/O operation was attempted on a filehandle that was
2456 never initialized. You need to do an open(), a sysopen(), or a socket()
2457 call, or call a constructor from the FileHandle package.
2461 (S internal) An internal warning that the grammar is screwed up.
2465 (S internal) An internal warning that the grammar is screwed up.
2467 =item Operation `%s': no method found, %s
2469 (F) An attempt was made to perform an overloaded operation for which no
2470 handler was defined. While some handlers can be autogenerated in terms
2471 of other handlers, there is no default handler for any operation, unless
2472 C<fallback> overloading key is specified to be true. See L<overload>.
2474 =item Operator or semicolon missing before %s
2476 (S ambiguous) You used a variable or subroutine call where the parser
2477 was expecting an operator. The parser has assumed you really meant to
2478 use an operator, but this is highly likely to be incorrect. For
2479 example, if you say "*foo *foo" it will be interpreted as if you said
2482 =item "our" variable %s redeclared
2484 (W misc) You seem to have already declared the same global once before
2485 in the current lexical scope.
2487 =item Out of memory!
2489 (X) The malloc() function returned 0, indicating there was insufficient
2490 remaining memory (or virtual memory) to satisfy the request. Perl has
2491 no option but to exit immediately.
2493 =item Out of memory during "large" request for %s
2495 (F) The malloc() function returned 0, indicating there was insufficient
2496 remaining memory (or virtual memory) to satisfy the request. However,
2497 the request was judged large enough (compile-time default is 64K), so a
2498 possibility to shut down by trapping this error is granted.
2500 =item Out of memory during request for %s
2502 (X|F) The malloc() function returned 0, indicating there was
2503 insufficient remaining memory (or virtual memory) to satisfy the
2506 The request was judged to be small, so the possibility to trap it
2507 depends on the way perl was compiled. By default it is not trappable.
2508 However, if compiled for this, Perl may use the contents of C<$^M> as an
2509 emergency pool after die()ing with this message. In this case the error
2510 is trappable I<once>, and the error message will include the line and file
2511 where the failed request happened.
2513 =item Out of memory during ridiculously large request
2515 (F) You can't allocate more than 2^31+"small amount" bytes. This error
2516 is most likely to be caused by a typo in the Perl program. e.g.,
2517 C<$arr[time]> instead of C<$arr[$time]>.
2519 =item Out of memory for yacc stack
2521 (F) The yacc parser wanted to grow its stack so it could continue
2522 parsing, but realloc() wouldn't give it more memory, virtual or
2525 =item @ outside of string
2527 (F) You had a pack template that specified an absolute position outside
2528 the string being unpacked. See L<perlfunc/pack>.
2530 =item %s package attribute may clash with future reserved word: %s
2532 (W reserved) A lowercase attribute name was used that had a
2533 package-specific handler. That name might have a meaning to Perl itself
2534 some day, even though it doesn't yet. Perhaps you should use a
2535 mixed-case attribute name, instead. See L<attributes>.
2539 (W io) A single call to write() produced more lines than can fit on a
2540 page. See L<perlform>.
2544 (P) An internal error.
2546 =item panic: ck_grep
2548 (P) Failed an internal consistency check trying to compile a grep.
2550 =item panic: ck_split
2552 (P) Failed an internal consistency check trying to compile a split.
2554 =item panic: corrupt saved stack index
2556 (P) The savestack was requested to restore more localized values than
2557 there are in the savestack.
2559 =item panic: del_backref
2561 (P) Failed an internal consistency check while trying to reset a weak
2566 (P) We popped the context stack to an eval context, and then discovered
2567 it wasn't an eval context.
2569 =item panic: pp_match%s
2571 (P) The internal pp_match() routine was called with invalid operational
2574 =item panic: do_subst
2576 (P) The internal pp_subst() routine was called with invalid operational
2579 =item panic: do_trans_%s
2581 (P) The internal do_trans routines were called with invalid operational
2586 (P) The library function frexp() failed, making printf("%f") impossible.
2590 (P) We popped the context stack to a context with the specified label,
2591 and then discovered it wasn't a context we know how to do a goto in.
2593 =item panic: INTERPCASEMOD
2595 (P) The lexer got into a bad state at a case modifier.
2597 =item panic: INTERPCONCAT
2599 (P) The lexer got into a bad state parsing a string with brackets.
2601 =item panic: kid popen errno read
2603 (F) forked child returned an incomprehensible message about its errno.
2607 (P) We popped the context stack to a block context, and then discovered
2608 it wasn't a block context.
2610 =item panic: leave_scope clearsv
2612 (P) A writable lexical variable became read-only somehow within the
2615 =item panic: leave_scope inconsistency
2617 (P) The savestack probably got out of sync. At least, there was an
2618 invalid enum on the top of it.
2620 =item panic: magic_killbackrefs
2622 (P) Failed an internal consistency check while trying to reset all weak
2623 references to an object.
2627 (P) Something requested a negative number of bytes of malloc.
2629 =item panic: mapstart
2631 (P) The compiler is screwed up with respect to the map() function.
2633 =item panic: null array
2635 (P) One of the internal array routines was passed a null AV pointer.
2637 =item panic: pad_alloc
2639 (P) The compiler got confused about which scratch pad it was allocating
2640 and freeing temporaries and lexicals from.
2642 =item panic: pad_free curpad
2644 (P) The compiler got confused about which scratch pad it was allocating
2645 and freeing temporaries and lexicals from.
2647 =item panic: pad_free po
2649 (P) An invalid scratch pad offset was detected internally.
2651 =item panic: pad_reset curpad
2653 (P) The compiler got confused about which scratch pad it was allocating
2654 and freeing temporaries and lexicals from.
2656 =item panic: pad_sv po
2658 (P) An invalid scratch pad offset was detected internally.
2660 =item panic: pad_swipe curpad
2662 (P) The compiler got confused about which scratch pad it was allocating
2663 and freeing temporaries and lexicals from.
2665 =item panic: pad_swipe po
2667 (P) An invalid scratch pad offset was detected internally.
2669 =item panic: pp_iter
2671 (P) The foreach iterator got called in a non-loop context frame.
2673 =item panic: pp_split
2675 (P) Something terrible went wrong in setting up for the split.
2677 =item panic: realloc
2679 (P) Something requested a negative number of bytes of realloc.
2681 =item panic: restartop
2683 (P) Some internal routine requested a goto (or something like it), and
2684 didn't supply the destination.
2688 (P) We popped the context stack to a subroutine or eval context, and
2689 then discovered it wasn't a subroutine or eval context.
2691 =item panic: scan_num
2693 (P) scan_num() got called on something that wasn't a number.
2695 =item panic: sv_insert
2697 (P) The sv_insert() routine was told to remove more string than there
2700 =item panic: top_env
2702 (P) The compiler attempted to do a goto, or something weird like that.
2706 (P) The lexer got into a bad state while processing a case modifier.
2708 =item panic: utf16_to_utf8: odd bytelen
2710 (P) Something tried to call utf16_to_utf8 with an odd (as opposed
2711 to even) byte length.
2713 =item Parentheses missing around "%s" list
2715 (W parenthesis) You said something like
2721 my ($foo, $bar) = @_;
2723 Remember that "my", "our", and "local" bind tighter than comma.
2725 =item Perl %s required--this is only version %s, stopped
2727 (F) The module in question uses features of a version of Perl more
2728 recent than the currently running version. How long has it been since
2729 you upgraded, anyway? See L<perlfunc/require>.
2731 =item PERL_SH_DIR too long
2733 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2734 C<sh>-shell in. See "PERL_SH_DIR" in L<perlos2>.
2736 =item perl: warning: Setting locale failed.
2738 (S) The whole warning message will look something like:
2740 perl: warning: Setting locale failed.
2741 perl: warning: Please check that your locale settings:
2744 are supported and installed on your system.
2745 perl: warning: Falling back to the standard locale ("C").
2747 Exactly what were the failed locale settings varies. In the above the
2748 settings were that the LC_ALL was "En_US" and the LANG had no value.
2749 This error means that Perl detected that you and/or your operating
2750 system supplier and/or system administrator have set up the so-called
2751 locale system but Perl could not use those settings. This was not
2752 dead serious, fortunately: there is a "default locale" called "C" that
2753 Perl can and will use, the script will be run. Before you really fix
2754 the problem, however, you will get the same error message each time
2755 you run Perl. How to really fix the problem can be found in
2756 L<perllocale> section B<LOCALE PROBLEMS>.
2758 =item perlio: argument list not closed for layer "%s"
2760 (S) When pushing a layer with arguments onto the Perl I/O system you forgot
2761 the ) that closes the argument list. (Layers take care of transforming
2762 data between external and internal representations.) Perl stopped parsing
2763 the layer list at this point and did not attempt to push this layer.
2764 If your program didn't explicitly request the failing operation, it may be
2765 the result of the value of the environment variable PERLIO.
2767 =item perlio: invalid separator character %s in attribute list
2769 (S) When pushing layers onto the Perl I/O system, something other than a
2770 colon or whitespace was seen between the elements of a layer list.
2771 If the previous attribute had a parenthesised parameter list, perhaps that
2772 list was terminated too soon.
2774 =item perlio: unknown layer "%s"
2776 (S) An attempt was made to push an unknown layer onto the Perl I/O
2777 system. (Layers take care of transforming data between external and
2778 internal representations.) Note that some layers, such as C<mmap>,
2779 are not supported in all environments. If your program didn't
2780 explicitly request the failing operation, it may be the result of the
2781 value of the environment variable PERLIO.
2783 =item Permission denied
2785 (F) The setuid emulator in suidperl decided you were up to no good.
2787 =item pid %x not a child
2789 (W exec) A warning peculiar to VMS. Waitpid() was asked to wait for a
2790 process which isn't a subprocess of the current process. While this is
2791 fine from VMS' perspective, it's probably not what you intended.
2793 =item P must have an explicit size
2795 (F) The unpack format P must have an explicit size, not "*".
2797 =item POSIX syntax [%s] belongs inside character classes in regex;
2799 marked by <-- HERE in m/%s/
2801 (W regexp) The character class constructs [: :], [= =], and [. .] go
2802 I<inside> character classes, the [] are part of the construct, for example:
2803 /[012[:alpha:]345]/. Note that [= =] and [. .] are not currently
2804 implemented; they are simply placeholders for future extensions and will
2805 cause fatal errors. The <-- HERE shows in the regular expression about
2806 where the problem was discovered. See L<perlre>.
2808 =item POSIX syntax [. .] is reserved for future extensions in regex;
2810 marked by <-- HERE in m/%s/
2812 (F regexp) Within regular expression character classes ([]) the syntax
2813 beginning with "[." and ending with ".]" is reserved for future extensions.
2814 If you need to represent those character sequences inside a regular
2815 expression character class, just quote the square brackets with the
2816 backslash: "\[." and ".\]". The <-- HERE shows in the regular expression
2817 about where the problem was discovered. See L<perlre>.
2819 =item POSIX syntax [= =] is reserved for future extensions in regex;
2821 marked by <-- HERE in m/%s/
2823 (F) Within regular expression character classes ([]) the syntax beginning
2824 with "[=" and ending with "=]" is reserved for future extensions. If you
2825 need to represent those character sequences inside a regular expression
2826 character class, just quote the square brackets with the backslash: "\[="
2827 and "=\]". The <-- HERE shows in the regular expression about where the
2828 problem was discovered. See L<perlre>.
2830 =item POSIX class [:%s:] unknown in regex;
2832 marked by <-- HERE in m/%s/
2834 (F) The class in the character class [: :] syntax is unknown. The <-- HERE
2835 shows in the regular expression about where the problem was discovered.
2836 Note that the POSIX character classes do B<not> have the C<is> prefix
2837 the corresponding C interfaces have: in other words, it's C<[[:print:]]>,
2838 not C<isprint>. See L<perlre>.
2840 =item POSIX getpgrp can't take an argument
2842 (F) Your system has POSIX getpgrp(), which takes no argument, unlike
2843 the BSD version, which takes a pid.
2845 =item Possible attempt to put comments in qw() list
2847 (W qw) qw() lists contain items separated by whitespace; as with literal
2848 strings, comment characters are not ignored, but are instead treated as
2849 literal data. (You may have used different delimiters than the
2850 parentheses shown here; braces are also frequently used.)
2852 You probably wrote something like this:
2859 when you should have written this:
2866 If you really want comments, build your list the
2867 old-fashioned way, with quotes and commas:
2871 'b', # another comment
2874 =item Possible attempt to separate words with commas
2876 (W qw) qw() lists contain items separated by whitespace; therefore
2877 commas aren't needed to separate the items. (You may have used
2878 different delimiters than the parentheses shown here; braces are also
2881 You probably wrote something like this:
2885 which puts literal commas into some of the list items. Write it without
2886 commas if you don't want them to appear in your data:
2890 =item Possible memory corruption: %s overflowed 3rd argument
2892 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
2893 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
2894 end of the buffer just in case. This sentinel byte got clobbered, and
2895 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
2897 =item Possible unintended interpolation of %s in string
2899 (W ambiguous) You said something like `@foo' in a double-quoted string
2900 but there was no array C<@foo> in scope at the time. If you wanted a
2901 literal @foo, then write it as \@foo; otherwise find out what happened
2902 to the array you apparently lost track of.
2904 =item Possible Y2K bug: %s
2906 (W y2k) You are concatenating the number 19 with another number, which
2907 could be a potential Year 2000 problem.
2909 =item pragma "attrs" is deprecated, use "sub NAME : ATTRS" instead
2911 (D deprecated) You have written something like this:
2915 use attrs qw(locked);
2918 You should use the new declaration syntax instead.
2924 The C<use attrs> pragma is now obsolete, and is only provided for
2925 backward-compatibility. See L<perlsub/"Subroutine Attributes">.
2927 =item Precedence problem: open %s should be open(%s)
2929 (S precedence) The old irregular construct
2933 is now misinterpreted as
2937 because of the strict regularization of Perl 5's grammar into unary and
2938 list operators. (The old open was a little of both.) You must put
2939 parentheses around the filehandle, or use the new "or" operator instead
2942 =item Premature end of script headers
2946 =item printf() on closed filehandle %s
2948 (W closed) The filehandle you're writing to got itself closed sometime
2949 before now. Check your control flow.
2951 =item print() on closed filehandle %s
2953 (W closed) The filehandle you're printing on got itself closed sometime
2954 before now. Check your control flow.
2956 =item Process terminated by SIG%s
2958 (W) This is a standard message issued by OS/2 applications, while *nix
2959 applications die in silence. It is considered a feature of the OS/2
2960 port. One can easily disable this by appropriate sighandlers, see
2961 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"
2964 =item Prototype mismatch: %s vs %s
2966 (S prototype) The subroutine being declared or defined had previously been
2967 declared or defined with a different function prototype.
2969 =item Prototype not terminated
2971 (F) You've omitted the closing parenthesis in a function prototype
2974 =item Quantifier in {,} bigger than %d in regex;
2976 marked by <-- HERE in m/%s/
2978 (F) There is currently a limit to the size of the min and max values of the
2979 {min,max} construct. The <-- HERE shows in the regular expression about where
2980 the problem was discovered. See L<perlre>.
2982 =item Quantifier unexpected on zero-length expression;
2984 marked by <-- HERE in m/%s/
2986 (W regexp) You applied a regular expression quantifier in a place where
2987 it makes no sense, such as on a zero-width assertion. Try putting the
2988 quantifier inside the assertion instead. For example, the way to match
2989 "abc" provided that it is followed by three repetitions of "xyz" is
2990 C</abc(?=(?:xyz){3})/>, not C</abc(?=xyz){3}/>.
2992 The <-- HERE shows in the regular expression about where the problem was
2995 =item Range iterator outside integer range
2997 (F) One (or both) of the numeric arguments to the range operator ".."
2998 are outside the range which can be represented by integers internally.
2999 One possible workaround is to force Perl to use magical string increment
3000 by prepending "0" to your numbers.
3002 =item readline() on closed filehandle %s
3004 (W closed) The filehandle you're reading from got itself closed sometime
3005 before now. Check your control flow.
3007 =item Reallocation too large: %lx
3009 (F) You can't allocate more than 64K on an MS-DOS machine.
3011 =item realloc() of freed memory ignored
3013 (S malloc) An internal routine called realloc() on something that had
3016 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
3018 (F debugging) You can't use the B<-D> option unless the code to produce
3019 the desired output is compiled into Perl, which entails some overhead,
3020 which is why it's currently left out of your copy.
3022 =item Recursive inheritance detected in package '%s'
3024 (F) More than 100 levels of inheritance were used. Probably indicates
3025 an unintended loop in your inheritance hierarchy.
3027 =item Recursive inheritance detected while looking for method %s
3029 (F) More than 100 levels of inheritance were encountered while invoking
3030 a method. Probably indicates an unintended loop in your inheritance
3033 =item Reference found where even-sized list expected
3035 (W misc) You gave a single reference where Perl was expecting a list
3036 with an even number of elements (for assignment to a hash). This usually
3037 means that you used the anon hash constructor when you meant to use
3038 parens. In any case, a hash requires key/value B<pairs>.
3040 %hash = { one => 1, two => 2, }; # WRONG
3041 %hash = [ qw/ an anon array / ]; # WRONG
3042 %hash = ( one => 1, two => 2, ); # right
3043 %hash = qw( one 1 two 2 ); # also fine
3045 =item Reference is already weak
3047 (W misc) You have attempted to weaken a reference that is already weak.
3048 Doing so has no effect.
3050 =item Reference miscount in sv_replace()
3052 (W internal) The internal sv_replace() function was handed a new SV with
3053 a reference count of other than 1.
3055 =item Reference to nonexistent group in regex;
3057 marked by <-- HERE in m/%s/
3059 (F) You used something like C<\7> in your regular expression, but there are
3060 not at least seven sets of capturing parentheses in the expression. If you
3061 wanted to have the character with value 7 inserted into the regular expression,
3062 prepend a zero to make the number at least two digits: C<\07>
3064 The <-- HERE shows in the regular expression about where the problem was
3067 =item regexp memory corruption
3069 (P) The regular expression engine got confused by what the regular
3070 expression compiler gave it.
3072 =item Regexp out of space
3074 (P) A "can't happen" error, because safemalloc() should have caught it
3077 =item Repeat count in pack overflows
3079 (F) You can't specify a repeat count so large that it overflows your
3080 signed integers. See L<perlfunc/pack>.
3082 =item Repeat count in unpack overflows
3084 (F) You can't specify a repeat count so large that it overflows your
3085 signed integers. See L<perlfunc/unpack>.
3087 =item Reversed %s= operator
3089 (W syntax) You wrote your assignment operator backwards. The = must
3090 always comes last, to avoid ambiguity with subsequent unary operators.
3092 =item Runaway format
3094 (F) Your format contained the ~~ repeat-until-blank sequence, but it
3095 produced 200 lines at once, and the 200th line looked exactly like the
3096 199th line. Apparently you didn't arrange for the arguments to exhaust
3097 themselves, either by using ^ instead of @ (for scalar variables), or by
3098 shifting or popping (for array variables). See L<perlform>.
3100 =item Scalar value @%s[%s] better written as $%s[%s]
3102 (W syntax) You've used an array slice (indicated by @) to select a
3103 single element of an array. Generally it's better to ask for a scalar
3104 value (indicated by $). The difference is that C<$foo[&bar]> always
3105 behaves like a scalar, both when assigning to it and when evaluating its
3106 argument, while C<@foo[&bar]> behaves like a list when you assign to it,
3107 and provides a list context to its subscript, which can do weird things
3108 if you're expecting only one subscript.
3110 On the other hand, if you were actually hoping to treat the array
3111 element as a list, you need to look into how references work, because
3112 Perl will not magically convert between scalars and lists for you. See
3115 =item Scalar value @%s{%s} better written as $%s{%s}
3117 (W syntax) You've used a hash slice (indicated by @) to select a single
3118 element of a hash. Generally it's better to ask for a scalar value
3119 (indicated by $). The difference is that C<$foo{&bar}> always behaves
3120 like a scalar, both when assigning to it and when evaluating its
3121 argument, while C<@foo{&bar}> behaves like a list when you assign to it,
3122 and provides a list context to its subscript, which can do weird things
3123 if you're expecting only one subscript.
3125 On the other hand, if you were actually hoping to treat the hash element
3126 as a list, you need to look into how references work, because Perl will
3127 not magically convert between scalars and lists for you. See
3130 =item Scalars leaked: %d
3132 (P) Something went wrong in Perl's internal bookkeeping of scalars:
3133 not all scalar variables were deallocated by the time Perl exited.
3134 What this usually indicates is a memory leak, which is of course bad,
3135 especially if the Perl program is intended to be long-running.
3137 =item Script is not setuid/setgid in suidperl
3139 (F) Oddly, the suidperl program was invoked on a script without a setuid
3140 or setgid bit set. This doesn't make much sense.
3142 =item Search pattern not terminated
3144 (F) The lexer couldn't find the final delimiter of a // or m{}
3145 construct. Remember that bracketing delimiters count nesting level.
3146 Missing the leading C<$> from a variable C<$m> may cause this error.
3148 =item %sseek() on unopened filehandle
3150 (W unopened) You tried to use the seek() or sysseek() function on a
3151 filehandle that was either never opened or has since been closed.
3153 =item select not implemented
3155 (F) This machine doesn't implement the select() system call.
3157 =item Self-ties of arrays and hashes are not supported
3159 (F) Self-ties are of arrays and hashes are not supported in
3160 the current implementation.
3162 =item Semicolon seems to be missing
3164 (W semicolon) A nearby syntax error was probably caused by a missing
3165 semicolon, or possibly some other missing operator, such as a comma.
3167 =item semi-panic: attempt to dup freed string
3169 (S internal) The internal newSVsv() routine was called to duplicate a
3170 scalar that had previously been marked as free.
3172 =item sem%s not implemented
3174 (F) You don't have System V semaphore IPC on your system.
3176 =item send() on closed socket %s
3178 (W closed) The socket you're sending to got itself closed sometime
3179 before now. Check your control flow.
3181 =item Sequence (? incomplete in regex; marked by <-- HERE in m/%s/
3183 (F) A regular expression ended with an incomplete extension (?. The <-- HERE
3184 shows in the regular expression about where the problem was discovered. See
3187 =item Sequence (?{...}) not terminated or not {}-balanced in regex;
3189 marked by <-- HERE in m/%s/
3191 (F) If the contents of a (?{...}) clause contains braces, they must balance
3192 for Perl to properly detect the end of the clause. The <-- HERE shows in
3193 the regular expression about where the problem was discovered. See
3196 =item Sequence (?%s...) not implemented in regex;
3198 marked by <-- HERE in m/%s/
3200 (F) A proposed regular expression extension has the character reserved but
3201 has not yet been written. The <-- HERE shows in the regular expression about
3202 where the problem was discovered. See L<perlre>.
3204 =item Sequence (?%s...) not recognized in regex;
3206 marked by <-- HERE in m/%s/
3208 (F) You used a regular expression extension that doesn't make sense. The
3209 <-- HERE shows in the regular expression about where the problem was
3210 discovered. See L<perlre>.
3212 =item Sequence (?#... not terminated in regex;
3214 marked by <-- HERE in m/%s/
3216 (F) A regular expression comment must be terminated by a closing
3217 parenthesis. Embedded parentheses aren't allowed. The <-- HERE shows in
3218 the regular expression about where the problem was discovered. See
3221 =item 500 Server error
3227 This is the error message generally seen in a browser window when trying
3228 to run a CGI program (including SSI) over the web. The actual error text
3229 varies widely from server to server. The most frequently-seen variants
3230 are "500 Server error", "Method (something) not permitted", "Document
3231 contains no data", "Premature end of script headers", and "Did not
3232 produce a valid header".
3234 B<This is a CGI error, not a Perl error>.
3236 You need to make sure your script is executable, is accessible by the
3237 user CGI is running the script under (which is probably not the user
3238 account you tested it under), does not rely on any environment variables
3239 (like PATH) from the user it isn't running under, and isn't in a
3240 location where the CGI server can't find it, basically, more or less.
3241 Please see the following for more information:
3243 http://www.perl.org/CGI_MetaFAQ.html
3244 http://www.htmlhelp.org/faq/cgifaq.html
3245 http://www.w3.org/Security/Faq/
3247 You should also look at L<perlfaq9>.
3249 =item setegid() not implemented
3251 (F) You tried to assign to C<$)>, and your operating system doesn't
3252 support the setegid() system call (or equivalent), or at least Configure
3255 =item seteuid() not implemented
3257 (F) You tried to assign to C<< $> >>, and your operating system doesn't
3258 support the seteuid() system call (or equivalent), or at least Configure
3261 =item setpgrp can't take arguments
3263 (F) Your system has the setpgrp() from BSD 4.2, which takes no
3264 arguments, unlike POSIX setpgid(), which takes a process ID and process
3267 =item setrgid() not implemented
3269 (F) You tried to assign to C<$(>, and your operating system doesn't
3270 support the setrgid() system call (or equivalent), or at least Configure
3273 =item setruid() not implemented
3275 (F) You tried to assign to C<$<>, and your operating system doesn't
3276 support the setruid() system call (or equivalent), or at least Configure
3279 =item setsockopt() on closed socket %s
3281 (W closed) You tried to set a socket option on a closed socket. Did you
3282 forget to check the return value of your socket() call? See
3283 L<perlfunc/setsockopt>.
3285 =item Setuid/gid script is writable by world
3287 (F) The setuid emulator won't run a script that is writable by the
3288 world, because the world might have written on it already.
3290 =item shm%s not implemented
3292 (F) You don't have System V shared memory IPC on your system.
3294 =item <> should be quotes
3296 (F) You wrote C<< require <file> >> when you should have written
3299 =item /%s/ should probably be written as "%s"
3301 (W syntax) You have used a pattern where Perl expected to find a string,
3302 as in the first argument to C<join>. Perl will treat the true or false
3303 result of matching the pattern against $_ as the string, which is
3304 probably not what you had in mind.
3306 =item shutdown() on closed socket %s
3308 (W closed) You tried to do a shutdown on a closed socket. Seems a bit
3311 =item SIG%s handler "%s" not defined
3313 (W signal) The signal handler named in %SIG doesn't, in fact, exist.
3314 Perhaps you put it into the wrong package?
3316 =item sort is now a reserved word
3318 (F) An ancient error message that almost nobody ever runs into anymore.
3319 But before sort was a keyword, people sometimes used it as a filehandle.
3321 =item Sort subroutine didn't return a numeric value
3323 (F) A sort comparison routine must return a number. You probably blew
3324 it by not using C<< <=> >> or C<cmp>, or by not using them correctly.
3325 See L<perlfunc/sort>.
3327 =item Sort subroutine didn't return single value
3329 (F) A sort comparison subroutine may not return a list value with more
3330 or less than one element. See L<perlfunc/sort>.
3332 =item splice() offset past end of array
3334 (W misc) You attempted to specify an offset that was past the end of
3335 the array passed to splice(). Splicing will instead commence at the end
3336 of the array, rather than past it. If this isn't what you want, try
3337 explicitly pre-extending the array by assigning $#array = $offset. See
3342 (P) The split was looping infinitely. (Obviously, a split shouldn't
3343 iterate more times than there are characters of input, which is what
3344 happened.) See L<perlfunc/split>.
3346 =item Statement unlikely to be reached
3348 (W exec) You did an exec() with some statement after it other than a
3349 die(). This is almost always an error, because exec() never returns
3350 unless there was a failure. You probably wanted to use system()
3351 instead, which does return. To suppress this warning, put the exec() in
3354 =item stat() on unopened filehandle %s
3356 (W unopened) You tried to use the stat() function on a filehandle that
3357 was either never opened or has since been closed.
3359 =item Stub found while resolving method `%s' overloading %s
3361 (P) Overloading resolution over @ISA tree may be broken by importation
3362 stubs. Stubs should never be implicitly created, but explicit calls to
3363 C<can> may break this.
3365 =item Subroutine %s redefined
3367 (W redefine) You redefined a subroutine. To suppress this warning, say
3370 no warnings 'redefine';
3371 eval "sub name { ... }";
3374 =item Substitution loop
3376 (P) The substitution was looping infinitely. (Obviously, a substitution
3377 shouldn't iterate more times than there are characters of input, which
3378 is what happened.) See the discussion of substitution in
3379 L<perlop/"Quote and Quote-like Operators">.
3381 =item Substitution pattern not terminated
3383 (F) The lexer couldn't find the interior delimiter of an s/// or s{}{}
3384 construct. Remember that bracketing delimiters count nesting level.
3385 Missing the leading C<$> from variable C<$s> may cause this error.
3387 =item Substitution replacement not terminated
3389 (F) The lexer couldn't find the final delimiter of an s/// or s{}{}
3390 construct. Remember that bracketing delimiters count nesting level.
3391 Missing the leading C<$> from variable C<$s> may cause this error.
3393 =item substr outside of string
3395 (W substr),(F) You tried to reference a substr() that pointed outside of
3396 a string. That is, the absolute value of the offset was larger than the
3397 length of the string. See L<perlfunc/substr>. This warning is fatal if
3398 substr is used in an lvalue context (as the left hand side of an
3399 assignment or as a subroutine argument for example).
3401 =item suidperl is no longer needed since %s
3403 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but
3404 a version of the setuid emulator somehow got run anyway.
3406 =item Switch (?(condition)... contains too many branches in regex;
3408 marked by <-- HERE in m/%s/
3410 (F) A (?(condition)if-clause|else-clause) construct can have at most two
3411 branches (the if-clause and the else-clause). If you want one or both to
3412 contain alternation, such as using C<this|that|other>, enclose it in
3413 clustering parentheses:
3415 (?(condition)(?:this|that|other)|else-clause)
3417 The <-- HERE shows in the regular expression about where the problem was
3418 discovered. See L<perlre>.
3420 =item Switch condition not recognized in regex;
3422 marked by <-- HERE in m/%s/
3424 (F) If the argument to the (?(...)if-clause|else-clause) construct is a
3425 number, it can be only a number. The <-- HERE shows in the regular expression
3426 about where the problem was discovered. See L<perlre>.
3428 =item switching effective %s is not implemented
3430 (F) While under the C<use filetest> pragma, we cannot switch the real
3431 and effective uids or gids.
3435 (F) Probably means you had a syntax error. Common reasons include:
3437 A keyword is misspelled.
3438 A semicolon is missing.
3440 An opening or closing parenthesis is missing.
3441 An opening or closing brace is missing.
3442 A closing quote is missing.
3444 Often there will be another error message associated with the syntax
3445 error giving more information. (Sometimes it helps to turn on B<-w>.)
3446 The error message itself often tells you where it was in the line when
3447 it decided to give up. Sometimes the actual error is several tokens
3448 before this, because Perl is good at understanding random input.
3449 Occasionally the line number may be misleading, and once in a blue moon
3450 the only way to figure out what's triggering the error is to call
3451 C<perl -c> repeatedly, chopping away half the program each time to see
3452 if the error went away. Sort of the cybernetic version of S<20
3455 =item syntax error at line %d: `%s' unexpected
3457 (A) You've accidentally run your script through the Bourne shell instead
3458 of Perl. Check the #! line, or manually feed your script into Perl
3461 =item syntax error in file %s at line %d, next 2 tokens "%s"
3463 (F) This error is likely to occur if you run a perl5 script through
3464 a perl4 interpreter, especially if the next 2 tokens are "use strict"
3465 or "my $var" or "our $var".
3469 (F) The final summary message when a C<perl -c> succeeds.
3471 =item System V %s is not implemented on this machine
3473 (F) You tried to do something with a function beginning with "sem",
3474 "shm", or "msg" but that System V IPC is not implemented in your
3475 machine. In some machines the functionality can exist but be
3476 unconfigured. Consult your system support.
3478 =item syswrite() on closed filehandle %s
3480 (W closed) The filehandle you're writing to got itself closed sometime
3481 before now. Check your control flow.
3483 =item Target of goto is too deeply nested
3485 (F) You tried to use C<goto> to reach a label that was too deeply nested
3486 for Perl to reach. Perl is doing you a favor by refusing.
3488 =item tell() on unopened filehandle
3490 (W unopened) You tried to use the tell() function on a filehandle that
3491 was either never opened or has since been closed.
3493 =item That use of $[ is unsupported
3495 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted
3496 as a compiler directive. You may say only one of
3505 This is to prevent the problem of one module changing the array base out
3506 from under another module inadvertently. See L<perlvar/$[>.
3508 =item The crypt() function is unimplemented due to excessive paranoia
3510 (F) Configure couldn't find the crypt() function on your machine,
3511 probably because your vendor didn't supply it, probably because they
3512 think the U.S. Government thinks it's a secret, or at least that they
3513 will continue to pretend that it is. And if you quote me on that, I
3516 =item The %s function is unimplemented
3518 The function indicated isn't implemented on this architecture, according
3519 to the probings of Configure.
3521 =item The stat preceding %s wasn't an lstat
3523 (F) It makes no sense to test the current stat buffer for symbolic
3524 linkhood if the last stat that wrote to the stat buffer already went
3525 past the symlink to get to the real file. Use an actual filename
3528 =item This Perl can't reset CRTL environ elements (%s)
3530 =item This Perl can't set CRTL environ elements (%s=%s)
3532 (W internal) Warnings peculiar to VMS. You tried to change or delete an
3533 element of the CRTL's internal environ array, but your copy of Perl
3534 wasn't built with a CRTL that contained the setenv() function. You'll
3535 need to rebuild Perl with a CRTL that does, or redefine
3536 F<PERL_ENV_TABLES> (see L<perlvms>) so that the environ array isn't the
3537 target of the change to
3538 %ENV which produced the warning.
3540 =item times not implemented
3542 (F) Your version of the C library apparently doesn't do times(). I
3543 suspect you're not running on Unix.
3545 =item Too few args to syscall
3547 (F) There has to be at least one argument to syscall() to specify the
3548 system call to call, silly dilly.
3550 =item Too late for "B<-T>" option
3552 (X) The #! line (or local equivalent) in a Perl script contains the
3553 B<-T> option, but Perl was not invoked with B<-T> in its command line.
3554 This is an error because, by the time Perl discovers a B<-T> in a
3555 script, it's too late to properly taint everything from the environment.
3558 If the Perl script is being executed as a command using the #!
3559 mechanism (or its local equivalent), this error can usually be fixed by
3560 editing the #! line so that the B<-T> option is a part of Perl's first
3561 argument: e.g. change C<perl -n -T> to C<perl -T -n>.
3563 If the Perl script is being executed as C<perl scriptname>, then the
3564 B<-T> option must appear on the command line: C<perl -T scriptname>.
3566 =item Too late for "-%s" option
3568 (X) The #! line (or local equivalent) in a Perl script contains the
3569 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
3570 are not intended for use inside scripts. Use the C<use> pragma instead.
3572 =item Too late to run %s block
3574 (W void) A CHECK or INIT block is being defined during run time proper,
3575 when the opportunity to run them has already passed. Perhaps you are
3576 loading a file with C<require> or C<do> when you should be using C<use>
3577 instead. Or perhaps you should put the C<require> or C<do> inside a
3580 =item Too many args to syscall
3582 (F) Perl supports a maximum of only 14 args to syscall().
3584 =item Too many arguments for %s
3586 (F) The function requires fewer arguments than you specified.
3592 (A) You've accidentally run your script through B<csh> instead of Perl.
3593 Check the #! line, or manually feed your script into Perl yourself.
3595 =item Trailing \ in regex m/%s/
3597 (F) The regular expression ends with an unbackslashed backslash.
3598 Backslash it. See L<perlre>.
3600 =item Transliteration pattern not terminated
3602 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
3603 or y/// or y[][] construct. Missing the leading C<$> from variables
3604 C<$tr> or C<$y> may cause this error.
3606 =item Transliteration replacement not terminated
3608 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
3611 =item truncate not implemented
3613 (F) Your machine doesn't implement a file truncation mechanism that
3614 Configure knows about.
3616 =item Type of arg %d to %s must be %s (not %s)
3618 (F) This function requires the argument in that position to be of a
3619 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
3620 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
3621 {EXPR} forms as an explicit dereference. See L<perlref>.
3623 =item umask not implemented
3625 (F) Your machine doesn't implement the umask function and you tried to
3626 use it to restrict permissions for yourself (EXPR & 0700).
3628 =item Unable to create sub named "%s"
3630 (F) You attempted to create or access a subroutine with an illegal name.
3632 =item Unbalanced context: %d more PUSHes than POPs
3634 (W internal) The exit code detected an internal inconsistency in how
3635 many execution contexts were entered and left.
3637 =item Unbalanced saves: %d more saves than restores
3639 (W internal) The exit code detected an internal inconsistency in how
3640 many values were temporarily localized.
3642 =item Unbalanced scopes: %d more ENTERs than LEAVEs
3644 (W internal) The exit code detected an internal inconsistency in how
3645 many blocks were entered and left.
3647 =item Unbalanced tmps: %d more allocs than frees
3649 (W internal) The exit code detected an internal inconsistency in how
3650 many mortal scalars were allocated and freed.
3652 =item Undefined format "%s" called
3654 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3655 another package? See L<perlform>.
3657 =item Undefined sort subroutine "%s" called
3659 (F) The sort comparison routine specified doesn't seem to exist.
3660 Perhaps it's in a different package? See L<perlfunc/sort>.
3662 =item Undefined subroutine &%s called
3664 (F) The subroutine indicated hasn't been defined, or if it was, it has
3665 since been undefined.
3667 =item Undefined subroutine called
3669 (F) The anonymous subroutine you're trying to call hasn't been defined,
3670 or if it was, it has since been undefined.
3672 =item Undefined subroutine in sort
3674 (F) The sort comparison routine specified is declared but doesn't seem
3675 to have been defined yet. See L<perlfunc/sort>.
3677 =item Undefined top format "%s" called
3679 (F) The format indicated doesn't seem to exist. Perhaps it's really in
3680 another package? See L<perlform>.
3682 =item Undefined value assigned to typeglob
3684 (W misc) An undefined value was assigned to a typeglob, a la
3685 C<*foo = undef>. This does nothing. It's possible that you really mean
3688 =item %s: Undefined variable
3690 (A) You've accidentally run your script through B<csh> instead of Perl.
3691 Check the #! line, or manually feed your script into Perl yourself.
3693 =item unexec of %s into %s failed!
3695 (F) The unexec() routine failed for some reason. See your local FSF
3696 representative, who probably put it there in the first place.
3698 =item Unicode character %s is illegal
3700 (W utf8) Certain Unicode characters have been designated off-limits by
3701 the Unicode standard and should not be generated. If you really know
3702 what you are doing you can turn off this warning by C<no warnings 'utf8';>.
3704 =item Unknown BYTEORDER
3706 (F) There are no byte-swapping functions for a machine with this byte
3709 =item Unknown "re" subpragma '%s' (known ones are: %s)
3711 You tried to use an unknown subpragma of the "re" pragma.
3713 =item Unknown switch condition (?(%.2s in regex;
3715 marked by <-- HERE in m/%s/
3717 (F) The condition part of a (?(condition)if-clause|else-clause) construct
3718 is not known. The condition may be lookahead or lookbehind (the condition
3719 is true if the lookahead or lookbehind is true), a (?{...}) construct (the
3720 condition is true if the code evaluates to a true value), or a number (the
3721 condition is true if the set of capturing parentheses named by the number
3724 The <-- HERE shows in the regular expression about where the problem was
3725 discovered. See L<perlre>.
3727 =item Unknown open() mode '%s'
3729 (F) The second argument of 3-argument open() is not among the list
3730 of valid modes: C<< < >>, C<< > >>, C<<< >> >>>, C<< +< >>,
3731 C<< +> >>, C<<< +>> >>>, C<-|>, C<|->.
3733 =item Unknown process %x sent message to prime_env_iter: %s
3735 (P) An error peculiar to VMS. Perl was reading values for %ENV before
3736 iterating over it, and someone else stuck a message in the stream of
3737 data Perl expected. Someone's very confused, or perhaps trying to
3738 subvert Perl's population of %ENV for nefarious purposes.
3740 =item Unknown warnings category '%s'
3742 (F) An error issued by the C<warnings> pragma. You specified a warnings
3743 category that is unknown to perl at this point.
3745 Note that if you want to enable a warnings category registered by a module
3746 (e.g. C<use warnings 'File::Find'>), you must have imported this module
3749 =item unmatched [ in regex; marked by <-- HERE in m/%s/
3751 (F) The brackets around a character class must match. If you wish to
3752 include a closing bracket in a character class, backslash it or put it
3753 first. The <-- HERE shows in the regular expression about where the problem
3754 was discovered. See L<perlre>.
3756 =item unmatched ( in regex; marked by <-- HERE in m/%s/
3758 (F) Unbackslashed parentheses must always be balanced in regular
3759 expressions. If you're a vi user, the % key is valuable for finding the
3760 matching parenthesis. The <-- HERE shows in the regular expression about
3761 where the problem was discovered. See L<perlre>.
3763 =item Unmatched right %s bracket
3765 (F) The lexer counted more closing curly or square brackets than opening
3766 ones, so you're probably missing a matching opening bracket. As a
3767 general rule, you'll find the missing one (so to speak) near the place
3768 you were last editing.
3770 =item Unquoted string "%s" may clash with future reserved word
3772 (W reserved) You used a bareword that might someday be claimed as a
3773 reserved word. It's best to put such a word in quotes, or capitalize it
3774 somehow, or insert an underbar into it. You might also declare it as a
3777 =item Unrecognized character %s
3779 (F) The Perl parser has no idea what to do with the specified character
3780 in your Perl script (or eval). Perhaps you tried to run a compressed
3781 script, a binary program, or a directory as a Perl program.
3783 =item /%s/: Unrecognized escape \\%c in character class passed through
3785 (W regexp) You used a backslash-character combination which is not
3786 recognized by Perl inside character classes. The character was
3787 understood literally.
3789 =item Unrecognized escape \\%c passed through in regex;
3791 marked by <-- HERE in m/%s/
3793 (W regexp) You used a backslash-character combination which is not
3794 recognized by Perl. This combination appears in an interpolated variable or
3795 a C<'>-delimited regular expression. The character was understood
3796 literally. The <-- HERE shows in the regular expression about where the
3797 escape was discovered.
3799 =item Unrecognized escape \\%c passed through
3801 (W misc) You used a backslash-character combination which is not
3804 =item Unrecognized signal name "%s"
3806 (F) You specified a signal name to the kill() function that was not
3807 recognized. Say C<kill -l> in your shell to see the valid signal names
3810 =item Unrecognized switch: -%s (-h will show valid options)
3812 (F) You specified an illegal option to Perl. Don't do that. (If you
3813 think you didn't do that, check the #! line to see if it's supplying the
3814 bad switch on your behalf.)
3816 =item Unsuccessful %s on filename containing newline
3818 (W newline) A file operation was attempted on a filename, and that
3819 operation failed, PROBABLY because the filename contained a newline,
3820 PROBABLY because you forgot to chomp() it off. See L<perlfunc/chomp>.
3822 =item Unsupported directory function "%s" called
3824 (F) Your machine doesn't support opendir() and readdir().
3826 =item Unsupported function %s
3828 (F) This machine doesn't implement the indicated function, apparently.
3829 At least, Configure doesn't think so.
3831 =item Unsupported function fork
3833 (F) Your version of executable does not support forking.
3835 Note that under some systems, like OS/2, there may be different flavors
3836 of Perl executables, some of which may support fork, some not. Try
3837 changing the name you call Perl by to C<perl_>, C<perl__>, and so on.
3839 =item Unsupported script encoding
3841 (F) Your program file begins with a Unicode Byte Order Mark (BOM) which
3842 declares it to be in a Unicode encoding that Perl cannot yet read.
3844 =item Unsupported socket function "%s" called
3846 (F) Your machine doesn't support the Berkeley socket mechanism, or at
3847 least that's what Configure thought.
3849 =item Unterminated attribute list
3851 (F) The lexer found something other than a simple identifier at the
3852 start of an attribute, and it wasn't a semicolon or the start of a
3853 block. Perhaps you terminated the parameter list of the previous
3854 attribute too soon. See L<attributes>.
3856 =item Unterminated attribute parameter in attribute list
3858 (F) The lexer saw an opening (left) parenthesis character while parsing
3859 an attribute list, but the matching closing (right) parenthesis
3860 character was not found. You may need to add (or remove) a backslash
3861 character to get your parentheses to balance. See L<attributes>.
3863 =item Unterminated compressed integer
3865 (F) An argument to unpack("w",...) was incompatible with the BER
3866 compressed integer format and could not be converted to an integer.
3867 See L<perlfunc/pack>.
3869 =item Unterminated <> operator
3871 (F) The lexer saw a left angle bracket in a place where it was expecting
3872 a term, so it's looking for the corresponding right angle bracket, and
3873 not finding it. Chances are you left some needed parentheses out
3874 earlier in the line, and you really meant a "less than".
3876 =item untie attempted while %d inner references still exist
3878 (W untie) A copy of the object returned from C<tie> (or C<tied>) was
3879 still valid when C<untie> was called.
3881 =item Useless (?%s) - use /%s modifier in regex;
3883 marked by <-- HERE in m/%s/
3885 (W regexp) You have used an internal modifier such as (?o) that has no
3886 meaning unless applied to the entire regexp:
3888 if ($string =~ /(?o)$pattern/) { ... }
3892 if ($string =~ /$pattern/o) { ... }
3894 The <-- HERE shows in the regular expression about
3895 where the problem was discovered. See L<perlre>.
3897 =item Useless (?-%s) - don't use /%s modifier in regex;
3899 marked by <-- HERE in m/%s/
3901 (W regexp) You have used an internal modifier such as (?-o) that has no
3902 meaning unless removed from the entire regexp:
3904 if ($string =~ /(?-o)$pattern/o) { ... }
3908 if ($string =~ /$pattern/) { ... }
3910 The <-- HERE shows in the regular expression about
3911 where the problem was discovered. See L<perlre>.
3913 =item Useless use of %s in void context
3915 (W void) You did something without a side effect in a context that does
3916 nothing with the return value, such as a statement that doesn't return a
3917 value from a block, or the left side of a scalar comma operator. Very
3918 often this points not to stupidity on your part, but a failure of Perl
3919 to parse your program the way you thought it would. For example, you'd
3920 get this if you mixed up your C precedence with Python precedence and
3925 when you meant to say
3927 ($one, $two) = (1, 2);
3929 Another common error is to use ordinary parentheses to construct a list
3930 reference when you should be using square or curly brackets, for
3935 when you should have said
3939 The square brackets explicitly turn a list value into a scalar value,
3940 while parentheses do not. So when a parenthesized list is evaluated in
3941 a scalar context, the comma is treated like C's comma operator, which
3942 throws away the left argument, which is not what you want. See
3943 L<perlref> for more on this.
3945 This warning will not be issued for numerical constants equal to 0 or 1
3946 since they are often used in statements like
3948 1 while sub_with_side_effects() ;
3950 String constants that would normally evaluate to 0 or 1 are warned
3953 =item Useless use of "re" pragma
3955 (W) You did C<use re;> without any arguments. That isn't very useful.
3957 =item Useless use of sort in scalar context
3959 (W void) You used sort in scalar context, as in :
3963 This is not very useful, and perl currently optimizes this away.
3965 =item Useless use of %s with no values
3967 (W syntax) You used the push() or unshift() function with no arguments
3968 apart from the array, like C<push(@x)> or C<unshift(@foo)>. That won't
3969 usually have any effect on the array, so is completely useless. It's
3970 possible in principle that push(@tied_array) could have some effect
3971 if the array is tied to a class which implements a PUSH method. If so,
3972 you can write it as C<push(@tied_array,())> to avoid this warning.
3974 =item "use" not allowed in expression
3976 (F) The "use" keyword is recognized and executed at compile time, and
3977 returns no useful value. See L<perlmod>.
3979 =item Use of bare << to mean <<"" is deprecated
3981 (D deprecated) You are now encouraged to use the explicitly quoted form
3982 if you wish to use an empty line as the terminator of the here-document.
3984 =item Use of *glob{FILEHANDLE} is deprecated
3986 (D deprecated) You are now encouraged to use the shorter *glob{IO} form
3987 to access the filehandle slot within a typeglob.
3989 =item Use of chdir('') or chdir(undef) as chdir() deprecated
3991 (D deprecated) chdir() with no arguments is documented to change to
3992 $ENV{HOME} or $ENV{LOGDIR}. chdir(undef) and chdir('') share this
3993 behavior, but that has been deprecated. In future versions they
3996 Be careful to check that what you pass to chdir() is defined and not
3997 blank, else you might find yourself in your home directory.
3999 =item Use of implicit split to @_ is deprecated
4001 (D deprecated) It makes a lot of work for the compiler when you clobber
4002 a subroutine's argument list, so it's better if you assign the results
4003 of a split() explicitly to an array (or list).
4005 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
4007 (D deprecated) As an (ahem) accidental feature, C<AUTOLOAD> subroutines
4008 are looked up as methods (using the C<@ISA> hierarchy) even when the
4009 subroutines to be autoloaded were called as plain functions (e.g.
4010 C<Foo::bar()>), not as methods (e.g. C<< Foo->bar() >> or C<<
4013 This bug will be rectified in future by using method lookup only for
4014 methods' C<AUTOLOAD>s. However, there is a significant base of existing
4015 code that may be using the old behavior. So, as an interim step, Perl
4016 currently issues an optional warning when non-methods use inherited
4019 The simple rule is: Inheritance will not work when autoloading
4020 non-methods. The simple fix for old code is: In any module that used
4021 to depend on inheriting C<AUTOLOAD> for non-methods from a base class
4022 named C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during
4025 In code that currently says C<use AutoLoader; @ISA = qw(AutoLoader);>
4026 you should remove AutoLoader from @ISA and change C<use AutoLoader;> to
4027 C<use AutoLoader 'AUTOLOAD';>.
4029 =item Use of -l on filehandle %s
4031 (W io) A filehandle represents an opened file, and when you opened the file
4032 it already went past any symlink you are presumably trying to look for.
4033 The operation returned C<undef>. Use a filename instead.
4035 =item Use of "package" with no arguments is deprecated
4037 (D deprecated) You used the C<package> keyword without specifying a package
4038 name. So no namespace is current at all. Using this can cause many
4039 otherwise reasonable constructs to fail in baffling ways. C<use strict;>
4042 =item Use of %s in printf format not supported
4044 (F) You attempted to use a feature of printf that is accessible from
4045 only C. This usually means there's a better way to do it in Perl.
4047 =item Use of $* is deprecated
4049 (D deprecated) This variable magically turned on multi-line pattern
4050 matching, both for you and for any luckless subroutine that you happen
4051 to call. You should use the new C<//m> and C<//s> modifiers now to do
4052 that without the dangerous action-at-a-distance effects of C<$*>.
4054 =item Use of %s is deprecated
4056 (D deprecated) The construct indicated is no longer recommended for use,
4057 generally because there's a better way to do it, and also because the
4058 old way has bad side effects.
4060 =item Use of $# is deprecated
4062 (D deprecated) This was an ill-advised attempt to emulate a poorly
4063 defined B<awk> feature. Use an explicit printf() or sprintf() instead.
4065 =item Use of reference "%s" as array index
4067 (W) You tried to use a reference as an array index; this probably
4068 isn't what you mean, because references in numerical context tend
4069 to be huge numbers, and so usually indicates programmer error.
4071 If you really do mean it, explicitly numify your reference, like so:
4072 C<$array[0+$ref]>. This warning is not given for overloaded objects,
4073 either, because you can overload the numification and stringification
4074 operators and then you assumedly know what you are doing.
4076 =item Use of reserved word "%s" is deprecated
4078 (D deprecated) The indicated bareword is a reserved word. Future
4079 versions of perl may use it as a keyword, so you're better off either
4080 explicitly quoting the word in a manner appropriate for its context of
4081 use, or using a different name altogether. The warning can be
4082 suppressed for subroutine names by either adding a C<&> prefix, or using
4083 a package qualifier, e.g. C<&our()>, or C<Foo::our()>.
4085 =item Use of tainted arguments in %s is deprecated
4087 (W taint) You have supplied C<system()> or C<exec()> with multiple
4088 arguments and at least one of them is tainted. This used to be allowed
4089 but will become a fatal error in a future version of perl. Untaint your
4090 arguments. See L<perlsec>.
4092 =item Use of uninitialized value%s
4094 (W uninitialized) An undefined value was used as if it were already
4095 defined. It was interpreted as a "" or a 0, but maybe it was a mistake.
4096 To suppress this warning assign a defined value to your variables.
4098 To help you figure out what was undefined, perl tells you what operation
4099 you used the undefined value in. Note, however, that perl optimizes your
4100 program and the operation displayed in the warning may not necessarily
4101 appear literally in your program. For example, C<"that $foo"> is
4102 usually optimized into C<"that " . $foo>, and the warning will refer to
4103 the C<concatenation (.)> operator, even though there is no C<.> in your
4106 =item Using a hash as a reference is deprecated
4108 (D deprecated) You tried to use a hash as a reference, as in
4109 C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
4110 used to allow this syntax, but shouldn't have. It is now deprecated, and will
4111 be removed in a future version.
4113 =item Using an array as a reference is deprecated
4115 (D deprecated) You tried to use an array as a reference, as in
4116 C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
4117 allow this syntax, but shouldn't have. It is now deprecated, and will be
4118 removed in a future version.
4120 =item UTF-16 surrogate %s
4122 (W utf8) You tried to generate half of an UTF-16 surrogate by
4123 requesting a Unicode character between the code points 0xD800 and
4124 0xDFFF (inclusive). That range is reserved exclusively for the use of
4125 UTF-16 encoding (by having two 16-bit UCS-2 characters); but Perl
4126 encodes its characters in UTF-8, so what you got is a very illegal
4127 character. If you really know what you are doing you can turn off
4128 this warning by C<no warnings 'utf8';>.
4130 =item Value of %s can be "0"; test with defined()
4132 (W misc) In a conditional expression, you used <HANDLE>, <*> (glob),
4133 C<each()>, or C<readdir()> as a boolean value. Each of these constructs
4134 can return a value of "0"; that would make the conditional expression
4135 false, which is probably not what you intended. When using these
4136 constructs in conditional expressions, test their values with the
4137 C<defined> operator.
4139 =item Value of CLI symbol "%s" too long
4141 (W misc) A warning peculiar to VMS. Perl tried to read the value of an
4142 %ENV element from a CLI symbol table, and found a resultant string
4143 longer than 1024 characters. The return value has been truncated to
4146 =item Variable "%s" is not imported%s
4148 (F) While "use strict" in effect, you referred to a global variable that
4149 you apparently thought was imported from another module, because
4150 something else of the same name (usually a subroutine) is exported by
4151 that module. It usually means you put the wrong funny character on the
4152 front of your variable.
4154 =item "%s" variable %s masks earlier declaration in same %s
4156 (W misc) A "my" or "our" variable has been redeclared in the current
4157 scope or statement, effectively eliminating all access to the previous
4158 instance. This is almost always a typographical error. Note that the
4159 earlier variable will still exist until the end of the scope or until
4160 all closure referents to it are destroyed.
4162 =item Variable "%s" may be unavailable
4164 (W closure) An inner (nested) I<anonymous> subroutine is inside a
4165 I<named> subroutine, and outside that is another subroutine; and the
4166 anonymous (innermost) subroutine is referencing a lexical variable
4167 defined in the outermost subroutine. For example:
4169 sub outermost { my $a; sub middle { sub { $a } } }
4171 If the anonymous subroutine is called or referenced (directly or
4172 indirectly) from the outermost subroutine, it will share the variable as
4173 you would expect. But if the anonymous subroutine is called or
4174 referenced when the outermost subroutine is not active, it will see the
4175 value of the shared variable as it was before and during the *first*
4176 call to the outermost subroutine, which is probably not what you want.
4178 In these circumstances, it is usually best to make the middle subroutine
4179 anonymous, using the C<sub {}> syntax. Perl has specific support for
4180 shared variables in nested anonymous subroutines; a named subroutine in
4181 between interferes with this feature.
4183 =item Variable syntax
4185 (A) You've accidentally run your script through B<csh> instead
4186 of Perl. Check the #! line, or manually feed your script into
4189 =item Variable "%s" will not stay shared
4191 (W closure) An inner (nested) I<named> subroutine is referencing a
4192 lexical variable defined in an outer subroutine.
4194 When the inner subroutine is called, it will probably see the value of
4195 the outer subroutine's variable as it was before and during the *first*
4196 call to the outer subroutine; in this case, after the first call to the
4197 outer subroutine is complete, the inner and outer subroutines will no
4198 longer share a common value for the variable. In other words, the
4199 variable will no longer be shared.
4201 Furthermore, if the outer subroutine is anonymous and references a
4202 lexical variable outside itself, then the outer and inner subroutines
4203 will I<never> share the given variable.
4205 This problem can usually be solved by making the inner subroutine
4206 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
4207 reference variables in outer subroutines are called or referenced, they
4208 are automatically rebound to the current values of such variables.
4210 =item Variable length lookbehind not implemented in regex;
4212 marked by <-- HERE in m/%s/
4214 (F) Lookbehind is allowed only for subexpressions whose length is fixed and
4215 known at compile time. The <-- HERE shows in the regular expression about
4216 where the problem was discovered. See L<perlre>.
4218 =item Version number must be a constant number
4220 (P) The attempt to translate a C<use Module n.n LIST> statement into
4221 its equivalent C<BEGIN> block found an internal inconsistency with
4224 =item v-string in use/require is non-portable
4226 (W) The use of v-strings is non-portable to older, pre-5.6, Perls.
4227 If you want your scripts to be backward portable, use the floating
4228 point version number: for example, instead of C<use 5.6.1> say
4229 C<use 5.006_001>. This of course won't help: the older Perls
4230 won't suddenly start understanding newer features, but at least
4231 they will show a sensible error message indicating the required
4234 =item Warning: something's wrong
4236 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
4237 you called it with no args and C<$_> was empty.
4239 =item Warning: unable to close filehandle %s properly
4241 (S) The implicit close() done by an open() got an error indication on
4242 the close(). This usually indicates your file system ran out of disk
4245 =item Warning: Use of "%s" without parentheses is ambiguous
4247 (S ambiguous) You wrote a unary operator followed by something that
4248 looks like a binary operator that could also have been interpreted as a
4249 term or unary operator. For instance, if you know that the rand
4250 function has a default argument of 1.0, and you write
4254 you may THINK you wrote the same thing as
4258 but in actual fact, you got
4262 So put in parentheses to say what you really mean.
4264 =item Wide character in %s
4266 (W utf8) Perl met a wide character (>255) when it wasn't expecting
4267 one. This warning is by default on for I/O (like print) but can be
4268 turned off by C<no warnings 'utf8';>. You are supposed to explicitly
4269 mark the filehandle with an encoding, see L<open> and L<perlfunc/binmode>.
4271 =item write() on closed filehandle %s
4273 (W closed) The filehandle you're writing to got itself closed sometime
4274 before now. Check your control flow.
4276 =item X outside of string
4278 (F) You had a pack template that specified a relative position before
4279 the beginning of the string being unpacked. See L<perlfunc/pack>.
4281 =item x outside of string
4283 (F) You had a pack template that specified a relative position after
4284 the end of the string being unpacked. See L<perlfunc/pack>.
4286 =item Xsub "%s" called in sort
4288 (F) The use of an external subroutine as a sort comparison is not yet
4291 =item Xsub called in sort
4293 (F) The use of an external subroutine as a sort comparison is not yet
4296 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
4298 (F) And you probably never will, because you probably don't have the
4299 sources to your kernel, and your vendor probably doesn't give a rip
4300 about what you want. Your best bet is to put a setuid C wrapper around
4303 =item You need to quote "%s"
4305 (W syntax) You assigned a bareword as a signal handler name.
4306 Unfortunately, you already have a subroutine of that name declared,
4307 which means that Perl 5 will try to call the subroutine when the
4308 assignment is executed, which is probably not what you want. (If it IS
4309 what you want, put an & in front.)