3 perldiag - various Perl diagnostics
7 These messages are classified as follows (listed in increasing order of
10 (W) A warning (optional).
11 (D) A deprecation (optional).
12 (S) A severe warning (mandatory).
13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
15 (X) A very fatal error (nontrappable).
16 (A) An alien error message (not generated by Perl).
18 Optional warnings are enabled by using the B<-w> switch. Warnings may
19 be captured by setting C<$SIG{__WARN__}> to a reference to a routine that
20 will be called on each warning instead of printing it. See L<perlvar>.
21 Trappable errors may be trapped using the eval operator. See
24 Some of these messages are generic. Spots that vary are denoted with a %s,
25 just as in a printf format. Note that some messages start with a %s!
26 The symbols C<"%-?@> sort before the letters, while C<[> and C<\> sort after.
30 =item "my" variable %s can't be in a package
32 (F) Lexically scoped variables aren't in a package, so it doesn't make sense
33 to try to declare one with a package qualifier on the front. Use local()
34 if you want to localize a package variable.
36 =item "my" variable %s masks earlier declaration in same scope
38 (S) A lexical variable has been redeclared in the same scope, effectively
39 eliminating all access to the previous instance. This is almost always
40 a typographical error. Note that the earlier variable will still exist
41 until the end of the scope or until all closure referents to it are
44 =item "no" not allowed in expression
46 (F) The "no" keyword is recognized and executed at compile time, and returns
47 no useful value. See L<perlmod>.
49 =item "use" not allowed in expression
51 (F) The "use" keyword is recognized and executed at compile time, and returns
52 no useful value. See L<perlmod>.
54 =item % may only be used in unpack
56 (F) You can't pack a string by supplying a checksum, because the
57 checksumming process loses information, and you can't go the other
58 way. See L<perlfunc/unpack>.
60 =item %s (...) interpreted as function
62 (W) You've run afoul of the rule that says that any list operator followed
63 by parentheses turns into a function, with all the list operators arguments
64 found inside the parentheses. See L<perlop/Terms and List Operators (Leftward)>.
66 =item %s argument is not a HASH element
68 (F) The argument to exists() must be a hash element, such as
73 =item %s argument is not a HASH element or slice
75 (F) The argument to delete() must be either a hash element, such as
80 or a hash slice, such as
82 @foo{$bar, $baz, $xyzzy}
83 @{$ref->[12]}{"susie", "queue"}
85 =item %s did not return a true value
87 (F) A required (or used) file must return a true value to indicate that
88 it compiled correctly and ran its initialization code correctly. It's
89 traditional to end such a file with a "1;", though any true value would
90 do. See L<perlfunc/require>.
92 =item %s found where operator expected
94 (S) The Perl lexer knows whether to expect a term or an operator. If it
95 sees what it knows to be a term when it was expecting to see an operator,
96 it gives you this warning. Usually it indicates that an operator or
97 delimiter was omitted, such as a semicolon.
99 =item %s had compilation errors
101 (F) The final summary message when a C<perl -c> fails.
103 =item %s has too many errors
105 (F) The parser has given up trying to parse the program after 10 errors.
106 Further error messages would likely be uninformative.
108 =item %s matches null string many times
110 (W) The pattern you've specified would be an infinite loop if the
111 regular expression engine didn't specifically check for that. See L<perlre>.
113 =item %s never introduced
115 (S) The symbol in question was declared but somehow went out of scope
116 before it could possibly have been used.
120 (F) The final summary message when a C<perl -c> succeeds.
122 =item %s: Command not found
124 (A) You've accidentally run your script through B<csh> instead
125 of Perl. Check the #! line, or manually feed your script into
128 =item %s: Expression syntax
130 (A) You've accidentally run your script through B<csh> instead
131 of Perl. Check the #! line, or manually feed your script into
134 =item %s: Undefined variable
136 (A) You've accidentally run your script through B<csh> instead
137 of Perl. Check the #! line, or manually feed your script into
142 (A) You've accidentally run your script through the Bourne shell
143 instead of Perl. Check the #! line, or manually feed your script
146 =item B<-P> not allowed for setuid/setgid script
148 (F) The script would have to be opened by the C preprocessor by name,
149 which provides a race condition that breaks security.
151 =item C<-T> and C<-B> not implemented on filehandles
153 (F) Perl can't peek at the stdio buffer of filehandles when it doesn't
154 know about your kind of stdio. You'll have to use a filename instead.
156 =item 500 Server error
160 =item ?+* follows nothing in regexp
162 (F) You started a regular expression with a quantifier. Backslash it
163 if you meant it literally. See L<perlre>.
165 =item @ outside of string
167 (F) You had a pack template that specified an absolute position outside
168 the string being unpacked. See L<perlfunc/pack>.
170 =item accept() on closed fd
172 (W) You tried to do an accept on a closed socket. Did you forget to check
173 the return value of your socket() call? See L<perlfunc/accept>.
175 =item Allocation too large: %lx
177 (X) You can't allocate more than 64K on an MS-DOS machine.
179 =item Allocation too large
181 (F) You can't allocate more than 2^31+"small amount" bytes.
183 =item Applying %s to %s will act on scalar(%s)
185 (W) The pattern match (//), substitution (s///), and translation (tr///)
186 operators work on scalar values. If you apply one of them to an array
187 or a hash, it will convert the array or hash to a scalar value -- the
188 length of an array, or the population info of a hash -- and then work on
189 that scalar value. This is probably not what you meant to do. See
190 L<perlfunc/grep> and L<perlfunc/map> for alternatives.
192 =item Arg too short for msgsnd
194 (F) msgsnd() requires a string at least as long as sizeof(long).
196 =item Ambiguous use of %s resolved as %s
198 (W)(S) You said something that may not be interpreted the way
199 you thought. Normally it's pretty easy to disambiguate it by supplying
200 a missing quote, operator, parenthesis pair or declaration.
202 =item Args must match #! line
204 (F) The setuid emulator requires that the arguments Perl was invoked
205 with match the arguments specified on the #! line. Since some systems
206 impose a one-argument limit on the #! line, try combining switches;
207 for example, turn C<-w -U> into C<-wU>.
209 =item Argument "%s" isn't numeric%s
211 (W) The indicated string was fed as an argument to an operator that
212 expected a numeric value instead. If you're fortunate the message
213 will identify which operator was so unfortunate.
215 =item Array @%s missing the @ in argument %d of %s()
217 (D) Really old Perl let you omit the @ on array names in some spots. This
218 is now heavily deprecated.
220 =item assertion botched: %s
222 (P) The malloc package that comes with Perl had an internal failure.
224 =item Assertion failed: file "%s"
226 (P) A general assertion failed. The file in question must be examined.
228 =item Assignment to both a list and a scalar
230 (F) If you assign to a conditional operator, the 2nd and 3rd arguments
231 must either both be scalars or both be lists. Otherwise Perl won't
232 know which context to supply to the right side.
234 =item Attempt to free non-arena SV: 0x%lx
236 (P) All SV objects are supposed to be allocated from arenas that will
237 be garbage collected on exit. An SV was discovered to be outside any
240 =item Attempt to free nonexistent shared string
242 (P) Perl maintains a reference counted internal table of strings to
243 optimize the storage and access of hash keys and other strings. This
244 indicates someone tried to decrement the reference count of a string
245 that can no longer be found in the table.
247 =item Attempt to free temp prematurely
249 (W) Mortalized values are supposed to be freed by the free_tmps()
250 routine. This indicates that something else is freeing the SV before
251 the free_tmps() routine gets a chance, which means that the free_tmps()
252 routine will be freeing an unreferenced scalar when it does try to free
255 =item Attempt to free unreferenced glob pointers
257 (P) The reference counts got screwed up on symbol aliases.
259 =item Attempt to free unreferenced scalar
261 (W) Perl went to decrement the reference count of a scalar to see if it
262 would go to 0, and discovered that it had already gone to 0 earlier,
263 and should have been freed, and in fact, probably was freed. This
264 could indicate that SvREFCNT_dec() was called too many times, or that
265 SvREFCNT_inc() was called too few times, or that the SV was mortalized
266 when it shouldn't have been, or that memory has been corrupted.
268 =item Attempt to use reference as lvalue in substr
270 (W) You supplied a reference as the first argument to substr() used
271 as an lvalue, which is pretty strange. Perhaps you forgot to
272 dereference it first. See L<perlfunc/substr>.
274 =item Bad arg length for %s, is %d, should be %d
276 (F) You passed a buffer of the wrong size to one of msgctl(), semctl() or
277 shmctl(). In C parlance, the correct sizes are, respectively,
278 S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
279 S<sizeof(struct shmid_ds *)>.
281 =item Bad filehandle: %s
283 (F) A symbol was passed to something wanting a filehandle, but the symbol
284 has no filehandle associated with it. Perhaps you didn't do an open(), or
285 did it in another package.
287 =item Bad free() ignored
289 (S) An internal routine called free() on something that had never been
290 malloc()ed in the first place. Mandatory, but can be disabled by
291 setting environment variable C<PERL_BADFREE> to 1.
293 This message can be quite often seen with DB_File on systems with
294 "hard" dynamic linking, like C<AIX> and C<OS/2>. It is a bug of
295 C<Berkeley DB> which is left unnoticed if C<DB> uses I<forgiving>
300 (P) One of the internal hash routines was passed a null HV pointer.
302 =item Bad name after %s::
304 (F) You started to name a symbol by using a package prefix, and then didn't
305 finish the symbol. In particular, you can't interpolate outside of quotes,
314 $sym = "mypack::$var";
316 =item Bad symbol for array
318 (P) An internal request asked to add an array entry to something that
319 wasn't a symbol table entry.
321 =item Bad symbol for filehandle
323 (P) An internal request asked to add a filehandle entry to something that
324 wasn't a symbol table entry.
326 =item Bad symbol for hash
328 (P) An internal request asked to add a hash entry to something that
329 wasn't a symbol table entry.
331 =item Badly placed ()'s
333 (A) You've accidentally run your script through B<csh> instead
334 of Perl. Check the #! line, or manually feed your script into
337 =item Bareword "%s" not allowed while "strict subs" in use
339 (F) With "strict subs" in use, a bareword is only allowed as a
340 subroutine identifier, in curly braces or to the left of the "=>" symbol.
341 Perhaps you need to predeclare a subroutine?
343 =item BEGIN failed--compilation aborted
345 (F) An untrapped exception was raised while executing a BEGIN subroutine.
346 Compilation stops immediately and the interpreter is exited.
348 =item BEGIN not safe after errors--compilation aborted
350 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
351 implies a C<BEGIN {}>) after one or more compilation errors had
352 already occurred. Since the intended environment for the C<BEGIN {}>
353 could not be guaranteed (due to the errors), and since subsequent code
354 likely depends on its correct operation, Perl just gave up.
356 =item bind() on closed fd
358 (W) You tried to do a bind on a closed socket. Did you forget to check
359 the return value of your socket() call? See L<perlfunc/bind>.
361 =item Bizarre copy of %s in %s
363 (P) Perl detected an attempt to copy an internal value that is not copiable.
365 =item Callback called exit
367 (F) A subroutine invoked from an external package via perl_call_sv()
368 exited by calling exit.
370 =item Can't "goto" outside a block
372 (F) A "goto" statement was executed to jump out of what might look
373 like a block, except that it isn't a proper block. This usually
374 occurs if you tried to jump out of a sort() block or subroutine, which
375 is a no-no. See L<perlfunc/goto>.
377 =item Can't "last" outside a block
379 (F) A "last" statement was executed to break out of the current block,
380 except that there's this itty bitty problem called there isn't a
381 current block. Note that an "if" or "else" block doesn't count as a
382 "loopish" block, as doesn't a block given to sort(). You can usually double
383 the curlies to get the same effect though, because the inner curlies
384 will be considered a block that loops once. See L<perlfunc/last>.
386 =item Can't "next" outside a block
388 (F) A "next" statement was executed to reiterate the current block, but
389 there isn't a current block. Note that an "if" or "else" block doesn't
390 count as a "loopish" block, as doesn't a block given to sort(). You can
391 usually double the curlies to get the same effect though, because the inner
392 curlies will be considered a block that loops once. See L<perlfunc/next>.
394 =item Can't "redo" outside a block
396 (F) A "redo" statement was executed to restart the current block, but
397 there isn't a current block. Note that an "if" or "else" block doesn't
398 count as a "loopish" block, as doesn't a block given to sort(). You can
399 usually double the curlies to get the same effect though, because the inner
400 curlies will be considered a block that loops once. See L<perlfunc/redo>.
402 =item Can't bless non-reference value
404 (F) Only hard references may be blessed. This is how Perl "enforces"
405 encapsulation of objects. See L<perlobj>.
407 =item Can't break at that line
409 (S) A warning intended to only be printed while running within the debugger, indicating
410 the line number specified wasn't the location of a statement that could
413 =item Can't call method "%s" in empty package "%s"
415 (F) You called a method correctly, and it correctly indicated a package
416 functioning as a class, but that package doesn't have ANYTHING defined
417 in it, let alone methods. See L<perlobj>.
419 =item Can't call method "%s" on unblessed reference
421 (F) A method call must know in what package it's supposed to run. It
422 ordinarily finds this out from the object reference you supply, but
423 you didn't supply an object reference in this case. A reference isn't
424 an object reference until it has been blessed. See L<perlobj>.
426 =item Can't call method "%s" without a package or object reference
428 (F) You used the syntax of a method call, but the slot filled by the
429 object reference or package name contains an expression that returns
430 neither an object reference nor a package name. (Perhaps it's null?)
431 Something like this will reproduce the error:
434 process $BADREF 1,2,3;
435 $BADREF->process(1,2,3);
437 =item Can't chdir to %s
439 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
440 that you can chdir to, possibly because it doesn't exist.
442 =item Can't coerce %s to integer in %s
444 (F) Certain types of SVs, in particular real symbol table entries
445 (typeglobs), can't be forced to stop being what they are. So you can't
455 but then $foo no longer contains a glob.
457 =item Can't coerce %s to number in %s
459 (F) Certain types of SVs, in particular real symbol table entries
460 (typeglobs), can't be forced to stop being what they are.
462 =item Can't coerce %s to string in %s
464 (F) Certain types of SVs, in particular real symbol table entries
465 (typeglobs), can't be forced to stop being what they are.
467 =item Can't create pipe mailbox
469 (P) An error peculiar to VMS. The process is suffering from exhausted quotas
470 or other plumbing problems.
472 =item Can't declare %s in my
474 (F) Only scalar, array, and hash variables may be declared as lexical variables.
475 They must have ordinary identifiers as names.
477 =item Can't do inplace edit on %s: %s
479 (S) The creation of the new file failed for the indicated reason.
481 =item Can't do inplace edit without backup
483 (F) You're on a system such as MS-DOS that gets confused if you try reading
484 from a deleted (but still opened) file. You have to say C<-i.bak>, or some
487 =item Can't do inplace edit: %s E<gt> 14 characters
489 (S) There isn't enough room in the filename to make a backup name for the file.
491 =item Can't do inplace edit: %s is not a regular file
493 (S) You tried to use the B<-i> switch on a special file, such as a file in
494 /dev, or a FIFO. The file was ignored.
496 =item Can't do setegid!
498 (P) The setegid() call failed for some reason in the setuid emulator
501 =item Can't do seteuid!
503 (P) The setuid emulator of suidperl failed for some reason.
505 =item Can't do setuid
507 (F) This typically means that ordinary perl tried to exec suidperl to
508 do setuid emulation, but couldn't exec it. It looks for a name of the
509 form sperl5.000 in the same directory that the perl executable resides
510 under the name perl5.000, typically /usr/local/bin on Unix machines.
511 If the file is there, check the execute permissions. If it isn't, ask
512 your sysadmin why he and/or she removed it.
514 =item Can't do waitpid with flags
516 (F) This machine doesn't have either waitpid() or wait4(), so only waitpid()
517 without flags is emulated.
519 =item Can't do {n,m} with n E<gt> m
521 (F) Minima must be less than or equal to maxima. If you really want
522 your regexp to match something 0 times, just put {0}. See L<perlre>.
524 =item Can't emulate -%s on #! line
526 (F) The #! line specifies a switch that doesn't make sense at this point.
527 For example, it'd be kind of silly to put a B<-x> on the #! line.
529 =item Can't exec "%s": %s
531 (W) An system(), exec(), or piped open call could not execute the named
532 program for the indicated reason. Typical reasons include: the permissions
533 were wrong on the file, the file wasn't found in C<$ENV{PATH}>, the
534 executable in question was compiled for another architecture, or the
535 #! line in a script points to an interpreter that can't be run for
536 similar reasons. (Or maybe your system doesn't support #! at all.)
540 (F) Perl was trying to execute the indicated program for you because that's
541 what the #! line said. If that's not what you wanted, you may need to
542 mention "perl" on the #! line somewhere.
544 =item Can't execute %s
546 (F) You used the B<-S> switch, but the script to execute could not be found
547 in the PATH, or at least not with the correct permissions.
549 =item Can't find label %s
551 (F) You said to goto a label that isn't mentioned anywhere that it's possible
552 for us to go to. See L<perlfunc/goto>.
554 =item Can't find string terminator %s anywhere before EOF
556 (F) Perl strings can stretch over multiple lines. This message means that
557 the closing delimiter was omitted. Because bracketed quotes count nesting
558 levels, the following is missing its final parenthesis:
560 print q(The character '(' starts a side comment.)
564 (F) A fatal error occurred while trying to fork while opening a pipeline.
566 =item Can't get filespec - stale stat buffer?
568 (S) A warning peculiar to VMS. This arises because of the difference between
569 access checks under VMS and under the Unix model Perl assumes. Under VMS,
570 access checks are done by filename, rather than by bits in the stat buffer, so
571 that ACLs and other protections can be taken into account. Unfortunately, Perl
572 assumes that the stat buffer contains all the necessary information, and passes
573 it, instead of the filespec, to the access checking routine. It will try to
574 retrieve the filespec using the device name and FID present in the stat buffer,
575 but this works only if you haven't made a subsequent call to the CRTL stat()
576 routine, because the device name is overwritten with each call. If this warning
577 appears, the name lookup failed, and the access checking routine gave up and
578 returned FALSE, just to be conservative. (Note: The access checking routine
579 knows about the Perl C<stat> operator and file tests, so you shouldn't ever
580 see this warning in response to a Perl command; it arises only if some internal
581 code takes stat buffers lightly.)
583 =item Can't get pipe mailbox device name
585 (P) An error peculiar to VMS. After creating a mailbox to act as a pipe, Perl
586 can't retrieve its name for later use.
588 =item Can't get SYSGEN parameter value for MAXBUF
590 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
591 mailbox buffers to be, and didn't get an answer.
593 =item Can't goto subroutine outside a subroutine
595 (F) The deeply magical "goto subroutine" call can only replace one subroutine
596 call for another. It can't manufacture one out of whole cloth. In general
597 you should be calling it out of only an AUTOLOAD routine anyway. See
600 =item Can't localize a reference
602 (F) You said something like C<local $$ref>, which is not allowed because
603 the compiler can't determine whether $ref will end up pointing to anything
604 with a symbol table entry, and a symbol table entry is necessary to
607 =item Can't localize lexical variable %s
609 (F) You used local on a variable name that was previously declared as a
610 lexical variable using "my". This is not allowed. If you want to
611 localize a package variable of the same name, qualify it with the
614 =item Can't locate %s in @INC
616 (F) You said to do (or require, or use) a file that couldn't be found
617 in any of the libraries mentioned in @INC. Perhaps you need to set the
618 PERL5LIB or PERL5OPT environment variable to say where the extra library
619 is, or maybe the script needs to add the library name to @INC. Or maybe
620 you just misspelled the name of the file. See L<perlfunc/require>.
622 =item Can't locate object method "%s" via package "%s"
624 (F) You called a method correctly, and it correctly indicated a package
625 functioning as a class, but that package doesn't define that particular
626 method, nor does any of its base classes. See L<perlobj>.
628 =item Can't locate package %s for @%s::ISA
630 (W) The @ISA array contained the name of another package that doesn't seem
635 (F) The mktemp() routine failed for some reason while trying to process
636 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
638 =item Can't modify %s in %s
640 (F) You aren't allowed to assign to the item indicated, or otherwise try to
641 change it, such as with an auto-increment.
643 =item Can't modify nonexistent substring
645 (P) The internal routine that does assignment to a substr() was handed
648 =item Can't msgrcv to read-only var
650 (F) The target of a msgrcv must be modifiable to be used as a receive
653 =item Can't open %s: %s
655 (S) An inplace edit couldn't open the original file for the indicated reason.
656 Usually this is because you don't have read permission for the file.
658 =item Can't open bidirectional pipe
660 (W) You tried to say C<open(CMD, "|cmd|")>, which is not supported. You can
661 try any of several modules in the Perl library to do this, such as
662 IPC::Open2. Alternately, direct the pipe's output to a file using "E<gt>",
663 and then read it in under a different file handle.
665 =item Can't open error file %s as stderr
667 (F) An error peculiar to VMS. Perl does its own command line redirection, and
668 couldn't open the file specified after '2E<gt>' or '2E<gt>E<gt>' on the
669 command line for writing.
671 =item Can't open input file %s as stdin
673 (F) An error peculiar to VMS. Perl does its own command line redirection, and
674 couldn't open the file specified after 'E<lt>' on the command line for reading.
676 =item Can't open output file %s as stdout
678 (F) An error peculiar to VMS. Perl does its own command line redirection, and
679 couldn't open the file specified after 'E<gt>' or 'E<gt>E<gt>' on the command
682 =item Can't open output pipe (name: %s)
684 (P) An error peculiar to VMS. Perl does its own command line redirection, and
685 couldn't open the pipe into which to send data destined for stdout.
687 =item Can't open perl script "%s": %s
689 (F) The script you specified can't be opened for the indicated reason.
691 =item Can't rename %s to %s: %s, skipping file
693 (S) The rename done by the B<-i> switch failed for some reason, probably because
694 you don't have write permission to the directory.
696 =item Can't reopen input pipe (name: %s) in binary mode
698 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried to
699 reopen it to accept binary data. Alas, it failed.
701 =item Can't reswap uid and euid
703 (P) The setreuid() call failed for some reason in the setuid emulator
706 =item Can't return outside a subroutine
708 (F) The return statement was executed in mainline code, that is, where
709 there was no subroutine call to return out of. See L<perlsub>.
711 =item Can't stat script "%s"
713 (P) For some reason you can't fstat() the script even though you have
714 it open already. Bizarre.
716 =item Can't swap uid and euid
718 (P) The setreuid() call failed for some reason in the setuid emulator
721 =item Can't take log of %g
723 (F) Logarithms are defined on only positive real numbers.
725 =item Can't take sqrt of %g
727 (F) For ordinary real numbers, you can't take the square root of a
728 negative number. There's a Complex package available for Perl, though,
729 if you really want to do that.
731 =item Can't undef active subroutine
733 (F) You can't undefine a routine that's currently running. You can,
734 however, redefine it while it's running, and you can even undef the
735 redefined subroutine while the old routine is running. Go figure.
739 (F) You tried to unshift an "unreal" array that can't be unshifted, such
740 as the main Perl stack.
742 =item Can't upgrade that kind of scalar
744 (P) The internal sv_upgrade routine adds "members" to an SV, making
745 it into a more specialized kind of SV. The top several SV types are
746 so specialized, however, that they cannot be interconverted. This
747 message indicates that such a conversion was attempted.
749 =item Can't upgrade to undef
751 (P) The undefined SV is the bottom of the totem pole, in the scheme
752 of upgradability. Upgrading to undef indicates an error in the
753 code calling sv_upgrade.
755 =item Can't use "my %s" in sort comparison
757 (F) The global variables $a and $b are reserved for sort comparisons.
758 You mentioned $a or $b in the same line as the E<lt>=E<gt> or cmp operator,
759 and the variable had earlier been declared as a lexical variable.
760 Either qualify the sort variable with the package name, or rename the
763 =item Can't use %s for loop variable
765 (F) Only a simple scalar variable may be used as a loop variable on a foreach.
767 =item Can't use %s ref as %s ref
769 (F) You've mixed up your reference types. You have to dereference a
770 reference of the type needed. You can use the ref() function to
771 test the type of the reference, if need be.
773 =item Can't use \1 to mean $1 in expression
775 (W) In an ordinary expression, backslash is a unary operator that creates
776 a reference to its argument. The use of backslash to indicate a backreference
777 to a matched substring is valid only as part of a regular expression pattern.
778 Trying to do this in ordinary Perl code produces a value that prints
779 out looking like SCALAR(0xdecaf). Use the $1 form instead.
781 =item Can't use bareword ("%s") as %s ref while \"strict refs\" in use
783 (F) Only hard references are allowed by "strict refs". Symbolic references
784 are disallowed. See L<perlref>.
786 =item Can't use string ("%s") as %s ref while "strict refs" in use
788 (F) Only hard references are allowed by "strict refs". Symbolic references
789 are disallowed. See L<perlref>.
791 =item Can't use an undefined value as %s reference
793 (F) A value used as either a hard reference or a symbolic reference must
794 be a defined value. This helps to delurk some insidious errors.
796 =item Can't use global %s in "my"
798 (F) You tried to declare a magical variable as a lexical variable. This is
799 not allowed, because the magic can be tied to only one location (namely
800 the global variable) and it would be incredibly confusing to have
801 variables in your program that looked like magical variables but
804 =item Can't use subscript on %s
806 (F) The compiler tried to interpret a bracketed expression as a
807 subscript. But to the left of the brackets was an expression that
808 didn't look like an array reference, or anything else subscriptable.
810 =item Can't write to temp file for B<-e>: %s
812 (F) The write routine failed for some reason while trying to process
813 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
815 =item Can't x= to read-only value
817 (F) You tried to repeat a constant value (often the undefined value) with
818 an assignment operator, which implies modifying the value itself.
819 Perhaps you need to copy the value to a temporary, and repeat that.
821 =item Cannot open temporary file
823 (F) The create routine failed for some reason while trying to process
824 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
826 =item Cannot resolve method `%s' overloading `%s' in package `%s'
828 (F|P) Error resolving overloading specified by a method name (as
829 opposed to a subroutine reference): no such method callable via the
830 package. If method name is C<???>, this is an internal error.
832 =item chmod: mode argument is missing initial 0
834 (W) A novice will sometimes say
838 not realizing that 777 will be interpreted as a decimal number, equivalent
839 to 01411. Octal constants are introduced with a leading 0 in Perl, as in C.
841 =item Close on unopened file E<lt>%sE<gt>
843 (W) You tried to close a filehandle that was never opened.
845 =item Compilation failed in require
847 (F) Perl could not compile a file specified in a C<require> statement.
848 Perl uses this generic message when none of the errors that it encountered
849 were severe enough to halt compilation immediately.
851 =item connect() on closed fd
853 (W) You tried to do a connect on a closed socket. Did you forget to check
854 the return value of your socket() call? See L<perlfunc/connect>.
856 =item Constant subroutine %s redefined
858 (S) You redefined a subroutine which had previously been eligible for
859 inlining. See L<perlsub/"Constant Functions"> for commentary and
862 =item Constant subroutine %s undefined
864 (S) You undefined a subroutine which had previously been eligible for
865 inlining. See L<perlsub/"Constant Functions"> for commentary and
868 =item Copy method did not return a reference
870 (F) The method which overloads "=" is buggy. See L<overload/Copy Constructor>.
872 =item Corrupt malloc ptr 0x%lx at 0x%lx
874 (P) The malloc package that comes with Perl had an internal failure.
876 =item corrupted regexp pointers
878 (P) The regular expression engine got confused by what the regular
879 expression compiler gave it.
881 =item corrupted regexp program
883 (P) The regular expression engine got passed a regexp program without
884 a valid magic number.
886 =item Deep recursion on subroutine "%s"
888 (W) This subroutine has called itself (directly or indirectly) 100
889 times than it has returned. This probably indicates an infinite
890 recursion, unless you're writing strange benchmark programs, in which
891 case it indicates something else.
893 =item Did you mean &%s instead?
895 (W) You probably referred to an imported subroutine &FOO as $FOO or some such.
897 =item Did you mean $ or @ instead of %?
899 (W) You probably said %hash{$key} when you meant $hash{$key} or @hash{@keys}.
900 On the other hand, maybe you just meant %hash and got carried away.
904 (F) You passed die() an empty string (the equivalent of C<die "">) or
905 you called it with no args and both C<$@> and C<$_> were empty.
907 =item Do you need to predeclare %s?
909 (S) This is an educated guess made in conjunction with the message "%s
910 found where operator expected". It often means a subroutine or module
911 name is being referenced that hasn't been declared yet. This may be
912 because of ordering problems in your file, or because of a missing
913 "sub", "package", "require", or "use" statement. If you're
914 referencing something that isn't defined yet, you don't actually have
915 to define the subroutine or package before the current location. You
916 can use an empty "sub foo;" or "package FOO;" to enter a "forward"
919 =item Don't know how to handle magic of type '%s'
921 (P) The internal handling of magical variables has been cursed.
923 =item do_study: out of memory
925 (P) This should have been caught by safemalloc() instead.
927 =item Duplicate free() ignored
929 (S) An internal routine called free() on something that had already
932 =item elseif should be elsif
934 (S) There is no keyword "elseif" in Perl because Larry thinks it's
935 ugly. Your code will be interpreted as an attempt to call a method
936 named "elseif" for the class returned by the following block. This is
937 unlikely to be what you want.
939 =item END failed--cleanup aborted
941 (F) An untrapped exception was raised while executing an END subroutine.
942 The interpreter is immediately exited.
944 =item Error converting file specification %s
946 (F) An error peculiar to VMS. Because Perl may have to deal with file
947 specifications in either VMS or Unix syntax, it converts them to a
948 single form when it must operate on them directly. Either you've
949 passed an invalid file specification to Perl, or you've found a
950 case the conversion routines don't handle. Drat.
952 =item Execution of %s aborted due to compilation errors
954 (F) The final summary message when a Perl compilation fails.
956 =item Exiting eval via %s
958 (W) You are exiting an eval by unconventional means, such as
959 a goto, or a loop control statement.
961 =item Exiting pseudo-block via %s
963 (W) You are exiting a rather special block construct (like a sort block or
964 subroutine) by unconventional means, such as a goto, or a loop control
965 statement. See L<perlfunc/sort>.
967 =item Exiting subroutine via %s
969 (W) You are exiting a subroutine by unconventional means, such as
970 a goto, or a loop control statement.
972 =item Exiting substitution via %s
974 (W) You are exiting a substitution by unconventional means, such as
975 a return, a goto, or a loop control statement.
977 =item Fatal VMS error at %s, line %d
979 (P) An error peculiar to VMS. Something untoward happened in a VMS system
980 service or RTL routine; Perl's exit status should provide more details. The
981 filename in "at %s" and the line number in "line %d" tell you which section of
982 the Perl source code is distressed.
984 =item fcntl is not implemented
986 (F) Your machine apparently doesn't implement fcntl(). What is this, a
989 =item Filehandle %s never opened
991 (W) An I/O operation was attempted on a filehandle that was never initialized.
992 You need to do an open() or a socket() call, or call a constructor from
993 the FileHandle package.
995 =item Filehandle %s opened for only input
997 (W) You tried to write on a read-only filehandle. If you
998 intended it to be a read-write filehandle, you needed to open it with
999 "+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing. If
1000 you intended only to write the file, use "E<gt>" or "E<gt>E<gt>". See
1003 =item Filehandle opened for only input
1005 (W) You tried to write on a read-only filehandle. If you
1006 intended it to be a read-write filehandle, you needed to open it with
1007 "+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing. If
1008 you intended only to write the file, use "E<gt>" or "E<gt>E<gt>". See
1011 =item Final $ should be \$ or $name
1013 (F) You must now decide whether the final $ in a string was meant to be
1014 a literal dollar sign, or was meant to introduce a variable name
1015 that happens to be missing. So you have to put either the backslash or
1018 =item Final @ should be \@ or @name
1020 (F) You must now decide whether the final @ in a string was meant to be
1021 a literal "at" sign, or was meant to introduce a variable name
1022 that happens to be missing. So you have to put either the backslash or
1025 =item Format %s redefined
1027 (W) You redefined a format. To suppress this warning, say
1031 eval "format NAME =...";
1034 =item Format not terminated
1036 (F) A format must be terminated by a line with a solitary dot. Perl got
1037 to the end of your file without finding such a line.
1039 =item Found = in conditional, should be ==
1049 (or something like that).
1051 =item gdbm store returned %d, errno %d, key "%s"
1053 (S) A warning from the GDBM_File extension that a store failed.
1055 =item gethostent not implemented
1057 (F) Your C library apparently doesn't implement gethostent(), probably
1058 because if it did, it'd feel morally obligated to return every hostname
1061 =item get{sock,peer}name() on closed fd
1063 (W) You tried to get a socket or peer socket name on a closed socket.
1064 Did you forget to check the return value of your socket() call?
1066 =item getpwnam returned invalid UIC %#o for user "%s"
1068 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1069 C<getpwnam> operator returned an invalid UIC.
1072 =item Glob not terminated
1074 (F) The lexer saw a left angle bracket in a place where it was expecting
1075 a term, so it's looking for the corresponding right angle bracket, and not
1076 finding it. Chances are you left some needed parentheses out earlier in
1077 the line, and you really meant a "less than".
1079 =item Global symbol "%s" requires explicit package name
1081 (F) You've said "use strict vars", which indicates that all variables
1082 must either be lexically scoped (using "my"), or explicitly qualified to
1083 say which package the global variable is in (using "::").
1085 =item goto must have label
1087 (F) Unlike with "next" or "last", you're not allowed to goto an
1088 unspecified destination. See L<perlfunc/goto>.
1090 =item Had to create %s unexpectedly
1092 (S) A routine asked for a symbol from a symbol table that ought to have
1093 existed already, but for some reason it didn't, and had to be created on
1094 an emergency basis to prevent a core dump.
1096 =item Hash %%s missing the % in argument %d of %s()
1098 (D) Really old Perl let you omit the % on hash names in some spots. This
1099 is now heavily deprecated.
1101 =item Ill-formed logical name |%s| in prime_env_iter
1103 (W) A warning peculiar to VMS. A logical name was encountered when preparing
1104 to iterate over %ENV which violates the syntactic rules governing logical
1105 names. Because it cannot be translated normally, it is skipped, and will not
1106 appear in %ENV. This may be a benign occurrence, as some software packages
1107 might directly modify logical name tables and introduce nonstandard names,
1108 or it may indicate that a logical name table has been corrupted.
1110 =item Illegal character %s (carriage return)
1112 (F) A carriage return character was found in the input. This is an
1113 error, and not a warning, because carriage return characters can break
1114 multi-line strings, including here documents (e.g., C<print E<lt>E<lt>EOF;>).
1116 Under Unix, this error is usually caused by executing Perl code --
1117 either the main program, a module, or an eval'd string -- that was
1118 transferred over a network connection from a non-Unix system without
1119 properly converting the text file format.
1121 Under systems that use something other than '\n' to delimit lines of
1122 text, this error can also be caused by reading Perl code from a file
1123 handle that is in binary mode (as set by the C<binmode> operator).
1125 In either case, the Perl code in question will probably need to be
1126 converted with something like C<s/\x0D\x0A?/\n/g> before it can be
1129 =item Illegal division by zero
1131 (F) You tried to divide a number by 0. Either something was wrong in your
1132 logic, or you need to put a conditional in to guard against meaningless input.
1134 =item Illegal modulus zero
1136 (F) You tried to divide a number by 0 to get the remainder. Most numbers
1137 don't take to this kindly.
1139 =item Illegal octal digit
1141 (F) You used an 8 or 9 in a octal number.
1143 =item Illegal octal digit ignored
1145 (W) You may have tried to use an 8 or 9 in a octal number. Interpretation
1146 of the octal number stopped before the 8 or 9.
1148 =item Illegal switch in PERL5OPT: %s
1150 (X) The PERL5OPT environment variable may only be used to set the
1151 following switches: B<-[DIMUdmw]>.
1153 =item In string, @%s now must be written as \@%s
1155 (F) It used to be that Perl would try to guess whether you wanted an
1156 array interpolated or a literal @. It did this when the string was first
1157 used at runtime. Now strings are parsed at compile time, and ambiguous
1158 instances of @ must be disambiguated, either by prepending a backslash to
1159 indicate a literal, or by declaring (or using) the array within the
1160 program before the string (lexically). (Someday it will simply assume
1161 that an unbackslashed @ interpolates an array.)
1163 =item Insecure dependency in %s
1165 (F) You tried to do something that the tainting mechanism didn't like.
1166 The tainting mechanism is turned on when you're running setuid or setgid,
1167 or when you specify B<-T> to turn it on explicitly. The tainting mechanism
1168 labels all data that's derived directly or indirectly from the user,
1169 who is considered to be unworthy of your trust. If any such data is
1170 used in a "dangerous" operation, you get this error. See L<perlsec>
1171 for more information.
1173 =item Insecure directory in %s
1175 (F) You can't use system(), exec(), or a piped open in a setuid or setgid
1176 script if C<$ENV{PATH}> contains a directory that is writable by the world.
1181 (F) You can't use system(), exec(), or a piped open in a setuid or
1182 setgid script if C<$ENV{PATH}> is derived from data supplied (or
1183 potentially supplied) by the user. The script must set the path to a
1184 known value, using trustworthy data. See L<perlsec>.
1186 =item Integer overflow in hex number
1188 (S) The literal hex number you have specified is too big for your
1189 architecture. On a 32-bit architecture the largest hex literal is
1192 =item Integer overflow in octal number
1194 (S) The literal octal number you have specified is too big for your
1195 architecture. On a 32-bit architecture the largest octal literal is
1198 =item Internal inconsistency in tracking vforks
1200 (S) A warning peculiar to VMS. Perl keeps track of the number
1201 of times you've called C<fork> and C<exec>, to determine
1202 whether the current call to C<exec> should affect the current
1203 script or a subprocess (see L<perlvms/exec>). Somehow, this count
1204 has become scrambled, so Perl is making a guess and treating
1205 this C<exec> as a request to terminate the Perl script
1206 and execute the specified command.
1208 =item internal disaster in regexp
1210 (P) Something went badly wrong in the regular expression parser.
1212 =item internal error: glob failed
1214 (P) Something went wrong with the external program(s) used for C<glob>
1215 and C<E<lt>*.cE<gt>>. This may mean that your csh (C shell) is
1216 broken. If so, you should change all of the csh-related variables in
1217 config.sh: If you have tcsh, make the variables refer to it as if it
1218 were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them all
1219 empty (except that C<d_csh> should be C<'undef'>) so that Perl will
1220 think csh is missing. In either case, after editing config.sh, run
1221 C<./Configure -S> and rebuild Perl.
1223 =item internal urp in regexp at /%s/
1225 (P) Something went badly awry in the regular expression parser.
1227 =item invalid [] range in regexp
1229 (F) The range specified in a character class had a minimum character
1230 greater than the maximum character. See L<perlre>.
1232 =item ioctl is not implemented
1234 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1235 strange for a machine that supports C.
1237 =item junk on end of regexp
1239 (P) The regular expression parser is confused.
1241 =item Label not found for "last %s"
1243 (F) You named a loop to break out of, but you're not currently in a
1244 loop of that name, not even if you count where you were called from.
1245 See L<perlfunc/last>.
1247 =item Label not found for "next %s"
1249 (F) You named a loop to continue, but you're not currently in a loop of
1250 that name, not even if you count where you were called from. See
1253 =item Label not found for "redo %s"
1255 (F) You named a loop to restart, but you're not currently in a loop of
1256 that name, not even if you count where you were called from. See
1259 =item listen() on closed fd
1261 (W) You tried to do a listen on a closed socket. Did you forget to check
1262 the return value of your socket() call? See L<perlfunc/listen>.
1264 =item Method for operation %s not found in package %s during blessing
1266 (F) An attempt was made to specify an entry in an overloading table that
1267 doesn't resolve to a valid subroutine. See L<overload>.
1269 =item Might be a runaway multi-line %s string starting on line %d
1271 (S) An advisory indicating that the previous error may have been caused
1272 by a missing delimiter on a string or pattern, because it eventually
1273 ended earlier on the current line.
1275 =item Misplaced _ in number
1277 (W) An underline in a decimal constant wasn't on a 3-digit boundary.
1279 =item Missing $ on loop variable
1281 (F) Apparently you've been programming in B<csh> too much. Variables are always
1282 mentioned with the $ in Perl, unlike in the shells, where it can vary from
1283 one line to the next.
1285 =item Missing comma after first argument to %s function
1287 (F) While certain functions allow you to specify a filehandle or an
1288 "indirect object" before the argument list, this ain't one of them.
1290 =item Missing operator before %s?
1292 (S) This is an educated guess made in conjunction with the message "%s
1293 found where operator expected". Often the missing operator is a comma.
1295 =item Missing right bracket
1297 (F) The lexer counted more opening curly brackets (braces) than closing ones.
1298 As a general rule, you'll find it's missing near the place you were last
1301 =item Missing semicolon on previous line?
1303 (S) This is an educated guess made in conjunction with the message "%s
1304 found where operator expected". Don't automatically put a semicolon on
1305 the previous line just because you saw this message.
1307 =item Modification of a read-only value attempted
1309 (F) You tried, directly or indirectly, to change the value of a
1310 constant. You didn't, of course, try "2 = 1", because the compiler
1311 catches that. But an easy way to do the same thing is:
1313 sub mod { $_[0] = 1 }
1316 Another way is to assign to a substr() that's off the end of the string.
1318 =item Modification of noncreatable array value attempted, subscript %d
1320 (F) You tried to make an array value spring into existence, and the
1321 subscript was probably negative, even counting from end of the array
1324 =item Modification of noncreatable hash value attempted, subscript "%s"
1326 (F) You tried to make a hash value spring into existence, and it couldn't
1327 be created for some peculiar reason.
1329 =item Module name must be constant
1331 (F) Only a bare module name is allowed as the first argument to a "use".
1333 =item msg%s not implemented
1335 (F) You don't have System V message IPC on your system.
1337 =item Multidimensional syntax %s not supported
1339 (W) Multidimensional arrays aren't written like C<$foo[1,2,3]>. They're written
1340 like C<$foo[1][2][3]>, as in C.
1342 =item Name "%s::%s" used only once: possible typo
1344 (W) Typographical errors often show up as unique variable names.
1345 If you had a good reason for having a unique name, then just mention
1346 it again somehow to suppress the message. The C<use vars> pragma is
1347 provided for just this purpose.
1349 =item Negative length
1351 (F) You tried to do a read/write/send/recv operation with a buffer length
1352 that is less than 0. This is difficult to imagine.
1354 =item nested *?+ in regexp
1356 (F) You can't quantify a quantifier without intervening parentheses. So
1357 things like ** or +* or ?* are illegal.
1359 Note, however, that the minimal matching quantifiers, C<*?>, C<+?>, and C<??> appear
1360 to be nested quantifiers, but aren't. See L<perlre>.
1364 (F) The setuid emulator requires that scripts have a well-formed #! line
1365 even on machines that don't support the #! construct.
1367 =item No %s allowed while running setuid
1369 (F) Certain operations are deemed to be too insecure for a setuid or setgid
1370 script to even be allowed to attempt. Generally speaking there will be
1371 another way to do what you want that is, if not secure, at least securable.
1374 =item No B<-e> allowed in setuid scripts
1376 (F) A setuid script can't be specified by the user.
1378 =item No comma allowed after %s
1380 (F) A list operator that has a filehandle or "indirect object" is not
1381 allowed to have a comma between that and the following arguments.
1382 Otherwise it'd be just another one of the arguments.
1384 One possible cause for this is that you expected to have imported a
1385 constant to your name space with B<use> or B<import> while no such
1386 importing took place, it may for example be that your operating system
1387 does not support that particular constant. Hopefully you did use an
1388 explicit import list for the constants you expect to see, please see
1389 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
1390 would probably have caught this error earlier it naturally does not
1391 remedy the fact that your operating system still does not support that
1392 constant. Maybe you have a typo in the constants of the symbol import
1393 list of B<use> or B<import> or in the constant name at the line where
1394 this error was triggered?
1396 =item No command into which to pipe on command line
1398 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1399 and found a '|' at the end of the command line, so it doesn't know where you
1400 want to pipe the output from this command.
1402 =item No DB::DB routine defined
1404 (F) The currently executing code was compiled with the B<-d> switch,
1405 but for some reason the perl5db.pl file (or some facsimile thereof)
1406 didn't define a routine to be called at the beginning of each
1407 statement. Which is odd, because the file should have been required
1408 automatically, and should have blown up the require if it didn't parse
1411 =item No dbm on this machine
1413 (P) This is counted as an internal error, because every machine should
1414 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
1416 =item No DBsub routine
1418 (F) The currently executing code was compiled with the B<-d> switch,
1419 but for some reason the perl5db.pl file (or some facsimile thereof)
1420 didn't define a DB::sub routine to be called at the beginning of each
1421 ordinary subroutine call.
1423 =item No error file after 2E<gt> or 2E<gt>E<gt> on command line
1425 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1426 and found a '2E<gt>' or a '2E<gt>E<gt>' on the command line, but can't find
1427 the name of the file to which to write data destined for stderr.
1429 =item No input file after E<lt> on command line
1431 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1432 and found a 'E<lt>' on the command line, but can't find the name of the file
1433 from which to read data for stdin.
1435 =item No output file after E<gt> on command line
1437 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1438 and found a lone 'E<gt>' at the end of the command line, so it doesn't know
1439 where you wanted to redirect stdout.
1441 =item No output file after E<gt> or E<gt>E<gt> on command line
1443 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1444 and found a 'E<gt>' or a 'E<gt>E<gt>' on the command line, but can't find the
1445 name of the file to which to write data destined for stdout.
1447 =item No Perl script found in input
1449 (F) You called C<perl -x>, but no line was found in the file beginning
1450 with #! and containing the word "perl".
1452 =item No setregid available
1454 (F) Configure didn't find anything resembling the setregid() call for
1457 =item No setreuid available
1459 (F) Configure didn't find anything resembling the setreuid() call for
1462 =item No space allowed after B<-I>
1464 (F) The argument to B<-I> must follow the B<-I> immediately with no
1467 =item No such pipe open
1469 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
1470 close a pipe which hadn't been opened. This should have been caught earlier as
1471 an attempt to close an unopened filehandle.
1473 =item No such signal: SIG%s
1475 (W) You specified a signal name as a subscript to %SIG that was not recognized.
1476 Say C<kill -l> in your shell to see the valid signal names on your system.
1478 =item Not a CODE reference
1480 (F) Perl was trying to evaluate a reference to a code value (that is, a
1481 subroutine), but found a reference to something else instead. You can
1482 use the ref() function to find out what kind of ref it really was.
1483 See also L<perlref>.
1485 =item Not a format reference
1487 (F) I'm not sure how you managed to generate a reference to an anonymous
1488 format, but this indicates you did, and that it didn't exist.
1490 =item Not a GLOB reference
1492 (F) Perl was trying to evaluate a reference to a "typeglob" (that is,
1493 a symbol table entry that looks like C<*foo>), but found a reference to
1494 something else instead. You can use the ref() function to find out
1495 what kind of ref it really was. See L<perlref>.
1497 =item Not a HASH reference
1499 (F) Perl was trying to evaluate a reference to a hash value, but
1500 found a reference to something else instead. You can use the ref()
1501 function to find out what kind of ref it really was. See L<perlref>.
1503 =item Not a perl script
1505 (F) The setuid emulator requires that scripts have a well-formed #! line
1506 even on machines that don't support the #! construct. The line must
1509 =item Not a SCALAR reference
1511 (F) Perl was trying to evaluate a reference to a scalar value, but
1512 found a reference to something else instead. You can use the ref()
1513 function to find out what kind of ref it really was. See L<perlref>.
1515 =item Not a subroutine reference
1517 (F) Perl was trying to evaluate a reference to a code value (that is, a
1518 subroutine), but found a reference to something else instead. You can
1519 use the ref() function to find out what kind of ref it really was.
1520 See also L<perlref>.
1522 =item Not a subroutine reference in overload table
1524 (F) An attempt was made to specify an entry in an overloading table that
1525 doesn't somehow point to a valid subroutine. See L<overload>.
1527 =item Not an ARRAY reference
1529 (F) Perl was trying to evaluate a reference to an array value, but
1530 found a reference to something else instead. You can use the ref()
1531 function to find out what kind of ref it really was. See L<perlref>.
1533 =item Not enough arguments for %s
1535 (F) The function requires more arguments than you specified.
1537 =item Not enough format arguments
1539 (W) A format specified more picture fields than the next line supplied.
1542 =item Null filename used
1544 (F) You can't require the null filename, especially because on many machines
1545 that means the current directory! See L<perlfunc/require>.
1547 =item Null picture in formline
1549 (F) The first argument to formline must be a valid format picture
1550 specification. It was found to be empty, which probably means you
1551 supplied it an uninitialized value. See L<perlform>.
1553 =item NULL OP IN RUN
1555 (P) Some internal routine called run() with a null opcode pointer.
1559 (P) An attempt was made to realloc NULL.
1561 =item NULL regexp argument
1563 (P) The internal pattern matching routines blew it big time.
1565 =item NULL regexp parameter
1567 (P) The internal pattern matching routines are out of their gourd.
1569 =item Odd number of elements in hash list
1571 (S) You specified an odd number of elements to a hash list, which is odd,
1572 because hash lists come in key/value pairs.
1574 =item Offset outside string
1576 (F) You tried to do a read/write/send/recv operation with an offset
1577 pointing outside the buffer. This is difficult to imagine.
1578 The sole exception to this is that C<sysread()>ing past the buffer
1579 will extend the buffer and zero pad the new area.
1583 (S) An internal warning that the grammar is screwed up.
1587 (S) An internal warning that the grammar is screwed up.
1589 =item Operation `%s': no method found,%s
1591 (F) An attempt was made to perform an overloaded operation for which
1592 no handler was defined. While some handlers can be autogenerated in
1593 terms of other handlers, there is no default handler for any
1594 operation, unless C<fallback> overloading key is specified to be
1595 true. See L<overload>.
1597 =item Operator or semicolon missing before %s
1599 (S) You used a variable or subroutine call where the parser was
1600 expecting an operator. The parser has assumed you really meant
1601 to use an operator, but this is highly likely to be incorrect.
1602 For example, if you say "*foo *foo" it will be interpreted as
1603 if you said "*foo * 'foo'".
1605 =item Out of memory for yacc stack
1607 (F) The yacc parser wanted to grow its stack so it could continue parsing,
1608 but realloc() wouldn't give it more memory, virtual or otherwise.
1610 =item Out of memory!
1612 (X|F) The malloc() function returned 0, indicating there was insufficient
1613 remaining memory (or virtual memory) to satisfy the request.
1615 The request was judged to be small, so the possibility to trap it
1616 depends on the way perl was compiled. By default it is not trappable.
1617 However, if compiled for this, Perl may use the contents of C<$^M> as
1618 an emergency pool after die()ing with this message. In this case the
1619 error is trappable I<once>.
1621 =item Out of memory during request for %s
1623 (F) The malloc() function returned 0, indicating there was insufficient
1624 remaining memory (or virtual memory) to satisfy the request. However,
1625 the request was judged large enough (compile-time default is 64K), so
1626 a possibility to shut down by trapping this error is granted.
1630 (W) A single call to write() produced more lines than can fit on a page.
1633 =item panic: ck_grep
1635 (P) Failed an internal consistency check trying to compile a grep.
1637 =item panic: ck_split
1639 (P) Failed an internal consistency check trying to compile a split.
1641 =item panic: corrupt saved stack index
1643 (P) The savestack was requested to restore more localized values than there
1644 are in the savestack.
1648 (P) We popped the context stack to an eval context, and then discovered
1649 it wasn't an eval context.
1651 =item panic: do_match
1653 (P) The internal pp_match() routine was called with invalid operational data.
1655 =item panic: do_split
1657 (P) Something terrible went wrong in setting up for the split.
1659 =item panic: do_subst
1661 (P) The internal pp_subst() routine was called with invalid operational data.
1663 =item panic: do_trans
1665 (P) The internal do_trans() routine was called with invalid operational data.
1669 (P) We popped the context stack to a context with the specified label,
1670 and then discovered it wasn't a context we know how to do a goto in.
1672 =item panic: INTERPCASEMOD
1674 (P) The lexer got into a bad state at a case modifier.
1676 =item panic: INTERPCONCAT
1678 (P) The lexer got into a bad state parsing a string with brackets.
1682 (P) We popped the context stack to a block context, and then discovered
1683 it wasn't a block context.
1685 =item panic: leave_scope clearsv
1687 (P) A writable lexical variable became read-only somehow within the scope.
1689 =item panic: leave_scope inconsistency
1691 (P) The savestack probably got out of sync. At least, there was an
1692 invalid enum on the top of it.
1696 (P) Something requested a negative number of bytes of malloc.
1698 =item panic: mapstart
1700 (P) The compiler is screwed up with respect to the map() function.
1702 =item panic: null array
1704 (P) One of the internal array routines was passed a null AV pointer.
1706 =item panic: pad_alloc
1708 (P) The compiler got confused about which scratch pad it was allocating
1709 and freeing temporaries and lexicals from.
1711 =item panic: pad_free curpad
1713 (P) The compiler got confused about which scratch pad it was allocating
1714 and freeing temporaries and lexicals from.
1716 =item panic: pad_free po
1718 (P) An invalid scratch pad offset was detected internally.
1720 =item panic: pad_reset curpad
1722 (P) The compiler got confused about which scratch pad it was allocating
1723 and freeing temporaries and lexicals from.
1725 =item panic: pad_sv po
1727 (P) An invalid scratch pad offset was detected internally.
1729 =item panic: pad_swipe curpad
1731 (P) The compiler got confused about which scratch pad it was allocating
1732 and freeing temporaries and lexicals from.
1734 =item panic: pad_swipe po
1736 (P) An invalid scratch pad offset was detected internally.
1738 =item panic: pp_iter
1740 (P) The foreach iterator got called in a non-loop context frame.
1742 =item panic: realloc
1744 (P) Something requested a negative number of bytes of realloc.
1746 =item panic: restartop
1748 (P) Some internal routine requested a goto (or something like it), and
1749 didn't supply the destination.
1753 (P) We popped the context stack to a subroutine or eval context, and
1754 then discovered it wasn't a subroutine or eval context.
1756 =item panic: scan_num
1758 (P) scan_num() got called on something that wasn't a number.
1760 =item panic: sv_insert
1762 (P) The sv_insert() routine was told to remove more string than there
1765 =item panic: top_env
1767 (P) The compiler attempted to do a goto, or something weird like that.
1771 (P) The lexer got into a bad state while processing a case modifier.
1773 =item Pareneses missing around "%s" list
1775 (W) You said something like
1781 my ($foo, $bar) = @_;
1783 Remember that "my" and "local" bind closer than comma.
1785 =item Perl %3.3f required--this is only version %s, stopped
1787 (F) The module in question uses features of a version of Perl more recent
1788 than the currently running version. How long has it been since you upgraded,
1789 anyway? See L<perlfunc/require>.
1791 =item Permission denied
1793 (F) The setuid emulator in suidperl decided you were up to no good.
1795 =item pid %d not a child
1797 (W) A warning peculiar to VMS. Waitpid() was asked to wait for a process which
1798 isn't a subprocess of the current process. While this is fine from VMS'
1799 perspective, it's probably not what you intended.
1801 =item POSIX getpgrp can't take an argument
1803 (F) Your C compiler uses POSIX getpgrp(), which takes no argument, unlike
1804 the BSD version, which takes a pid.
1806 =item Possible attempt to put comments in qw() list
1808 (W) qw() lists contain items separated by whitespace; as with literal
1809 strings, comment characters are not ignored, but are instead treated
1810 as literal data. (You may have used different delimiters than the
1811 exclamation marks parentheses shown here; braces are also frequently
1814 You probably wrote something like this:
1821 when you should have written this:
1828 If you really want comments, build your list the
1829 old-fashioned way, with quotes and commas:
1833 'b', # another comment
1836 =item Possible attempt to separate words with commas
1838 (W) qw() lists contain items separated by whitespace; therefore commas
1839 aren't needed to separate the items. (You may have used different
1840 delimiters than the parentheses shown here; braces are also frequently
1843 You probably wrote something like this:
1847 which puts literal commas into some of the list items. Write it without
1848 commas if you don't want them to appear in your data:
1852 =item Possible memory corruption: %s overflowed 3rd argument
1854 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
1855 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
1856 end of the buffer just in case. This sentinel byte got clobbered, and
1857 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
1859 =item Precedence problem: open %s should be open(%s)
1861 (S) The old irregular construct
1865 is now misinterpreted as
1869 because of the strict regularization of Perl 5's grammar into unary
1870 and list operators. (The old open was a little of both.) You must
1871 put parentheses around the filehandle, or use the new "or" operator
1874 =item print on closed filehandle %s
1876 (W) The filehandle you're printing on got itself closed sometime before now.
1877 Check your logic flow.
1879 =item printf on closed filehandle %s
1881 (W) The filehandle you're writing to got itself closed sometime before now.
1882 Check your logic flow.
1884 =item Probable precedence problem on %s
1886 (W) The compiler found a bareword where it expected a conditional,
1887 which often indicates that an || or && was parsed as part of the
1888 last argument of the previous construct, for example:
1892 =item Prototype mismatch: %s vs %s
1894 (S) The subroutine being declared or defined had previously been declared
1895 or defined with a different function prototype.
1897 =item Read on closed filehandle E<lt>%sE<gt>
1899 (W) The filehandle you're reading from got itself closed sometime before now.
1900 Check your logic flow.
1902 =item Reallocation too large: %lx
1904 (F) You can't allocate more than 64K on an MS-DOS machine.
1906 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
1908 (F) You can't use the B<-D> option unless the code to produce the
1909 desired output is compiled into Perl, which entails some overhead,
1910 which is why it's currently left out of your copy.
1912 =item Recursive inheritance detected
1914 (F) More than 100 levels of inheritance were used. Probably indicates
1915 an unintended loop in your inheritance hierarchy.
1917 =item Recursive substitution detected
1919 (F) The replacement string of a substitution caused the recursive
1920 execution of that very same substituion. Perl cannot keep track of
1921 special variables (C<$1>, etc.) under such circumstances.
1923 =item Reference miscount in sv_replace()
1925 (W) The internal sv_replace() function was handed a new SV with a
1926 reference count of other than 1.
1928 =item regexp memory corruption
1930 (P) The regular expression engine got confused by what the regular
1931 expression compiler gave it.
1933 =item regexp out of space
1935 (P) A "can't happen" error, because safemalloc() should have caught it earlier.
1937 =item regexp too big
1939 (F) The current implementation of regular expressions uses shorts as
1940 address offsets within a string. Unfortunately this means that if
1941 the regular expression compiles to longer than 32767, it'll blow up.
1942 Usually when you want a regular expression this big, there is a better
1943 way to do it with multiple statements. See L<perlre>.
1945 =item Reversed %s= operator
1947 (W) You wrote your assignment operator backwards. The = must always
1948 comes last, to avoid ambiguity with subsequent unary operators.
1950 =item Runaway format
1952 (F) Your format contained the ~~ repeat-until-blank sequence, but it
1953 produced 200 lines at once, and the 200th line looked exactly like the
1954 199th line. Apparently you didn't arrange for the arguments to exhaust
1955 themselves, either by using ^ instead of @ (for scalar variables), or by
1956 shifting or popping (for array variables). See L<perlform>.
1958 =item Scalar value @%s[%s] better written as $%s[%s]
1960 (W) You've used an array slice (indicated by @) to select a single element of
1961 an array. Generally it's better to ask for a scalar value (indicated by $).
1962 The difference is that C<$foo[&bar]> always behaves like a scalar, both when
1963 assigning to it and when evaluating its argument, while C<@foo[&bar]> behaves
1964 like a list when you assign to it, and provides a list context to its
1965 subscript, which can do weird things if you're expecting only one subscript.
1967 On the other hand, if you were actually hoping to treat the array
1968 element as a list, you need to look into how references work, because
1969 Perl will not magically convert between scalars and lists for you. See
1972 =item Scalar value @%s{%s} better written as $%s{%s}
1974 (W) You've used a hash slice (indicated by @) to select a single element of
1975 a hash. Generally it's better to ask for a scalar value (indicated by $).
1976 The difference is that C<$foo{&bar}> always behaves like a scalar, both when
1977 assigning to it and when evaluating its argument, while C<@foo{&bar}> behaves
1978 like a list when you assign to it, and provides a list context to its
1979 subscript, which can do weird things if you're expecting only one subscript.
1981 On the other hand, if you were actually hoping to treat the hash
1982 element as a list, you need to look into how references work, because
1983 Perl will not magically convert between scalars and lists for you. See
1986 =item Script is not setuid/setgid in suidperl
1988 (F) Oddly, the suidperl program was invoked on a script without a setuid
1989 or setgid bit set. This doesn't make much sense.
1991 =item Search pattern not terminated
1993 (F) The lexer couldn't find the final delimiter of a // or m{}
1994 construct. Remember that bracketing delimiters count nesting level.
1996 =item seek() on unopened file
1998 (W) You tried to use the seek() function on a filehandle that was either
1999 never opened or has since been closed.
2001 =item select not implemented
2003 (F) This machine doesn't implement the select() system call.
2005 =item sem%s not implemented
2007 (F) You don't have System V semaphore IPC on your system.
2009 =item semi-panic: attempt to dup freed string
2011 (S) The internal newSVsv() routine was called to duplicate a scalar
2012 that had previously been marked as free.
2014 =item Semicolon seems to be missing
2016 (W) A nearby syntax error was probably caused by a missing semicolon,
2017 or possibly some other missing operator, such as a comma.
2019 =item Send on closed socket
2021 (W) The filehandle you're sending to got itself closed sometime before now.
2022 Check your logic flow.
2024 =item Sequence (?#... not terminated
2026 (F) A regular expression comment must be terminated by a closing
2027 parenthesis. Embedded parentheses aren't allowed. See L<perlre>.
2029 =item Sequence (?%s...) not implemented
2031 (F) A proposed regular expression extension has the character reserved
2032 but has not yet been written. See L<perlre>.
2034 =item Sequence (?%s...) not recognized
2036 (F) You used a regular expression extension that doesn't make sense.
2041 Also known as "500 Server error".
2043 B<This is a CGI error, not a Perl error>.
2045 You need to make sure your script is executable, is accessible by the user
2046 CGI is running the script under (which is probably not the user account you
2047 tested it under), does not rely on any environment variables (like PATH)
2048 from the user it isn't running under, and isn't in a location where the CGI
2049 server can't find it, basically, more or less. Please see the following
2050 for more information:
2052 http://www.perl.com/perl/faq/idiots-guide.html
2053 http://www.perl.com/perl/faq/perl-cgi-faq.html
2054 ftp://rtfm.mit.edu/pub/usenet/news.answers/www/cgi-faq
2055 http://hoohoo.ncsa.uiuc.edu/cgi/interface.html
2056 http://www-genome.wi.mit.edu/WWW/faqs/www-security-faq.html
2058 =item setegid() not implemented
2060 (F) You tried to assign to C<$)>, and your operating system doesn't support
2061 the setegid() system call (or equivalent), or at least Configure didn't
2064 =item seteuid() not implemented
2066 (F) You tried to assign to C<$E<gt>>, and your operating system doesn't support
2067 the seteuid() system call (or equivalent), or at least Configure didn't
2070 =item setrgid() not implemented
2072 (F) You tried to assign to C<$(>, and your operating system doesn't support
2073 the setrgid() system call (or equivalent), or at least Configure didn't
2076 =item setruid() not implemented
2078 (F) You tried to assign to C<$<lt>>, and your operating system doesn't support
2079 the setruid() system call (or equivalent), or at least Configure didn't
2082 =item Setuid/gid script is writable by world
2084 (F) The setuid emulator won't run a script that is writable by the world,
2085 because the world might have written on it already.
2087 =item shm%s not implemented
2089 (F) You don't have System V shared memory IPC on your system.
2091 =item shutdown() on closed fd
2093 (W) You tried to do a shutdown on a closed socket. Seems a bit superfluous.
2095 =item SIG%s handler "%s" not defined
2097 (W) The signal handler named in %SIG doesn't, in fact, exist. Perhaps you
2098 put it into the wrong package?
2100 =item sort is now a reserved word
2102 (F) An ancient error message that almost nobody ever runs into anymore.
2103 But before sort was a keyword, people sometimes used it as a filehandle.
2105 =item Sort subroutine didn't return a numeric value
2107 (F) A sort comparison routine must return a number. You probably blew
2108 it by not using C<E<lt>=E<gt>> or C<cmp>, or by not using them correctly.
2109 See L<perlfunc/sort>.
2111 =item Sort subroutine didn't return single value
2113 (F) A sort comparison subroutine may not return a list value with more
2114 or less than one element. See L<perlfunc/sort>.
2118 (P) The split was looping infinitely. (Obviously, a split shouldn't iterate
2119 more times than there are characters of input, which is what happened.)
2120 See L<perlfunc/split>.
2122 =item Stat on unopened file E<lt>%sE<gt>
2124 (W) You tried to use the stat() function (or an equivalent file test)
2125 on a filehandle that was either never opened or has since been closed.
2127 =item Statement unlikely to be reached
2129 (W) You did an exec() with some statement after it other than a die().
2130 This is almost always an error, because exec() never returns unless
2131 there was a failure. You probably wanted to use system() instead,
2132 which does return. To suppress this warning, put the exec() in a block
2135 =item Stub found while resolving method `%s' overloading `%s' in package `%s'
2137 (P) Overloading resolution over @ISA tree may be broken by importation stubs.
2138 Stubs should never be implicitely created, but explicit calls to C<can>
2141 =item Subroutine %s redefined
2143 (W) You redefined a subroutine. To suppress this warning, say
2147 eval "sub name { ... }";
2150 =item Substitution loop
2152 (P) The substitution was looping infinitely. (Obviously, a
2153 substitution shouldn't iterate more times than there are characters of
2154 input, which is what happened.) See the discussion of substitution in
2155 L<perlop/"Quote and Quote-like Operators">.
2157 =item Substitution pattern not terminated
2159 (F) The lexer couldn't find the interior delimiter of a s/// or s{}{}
2160 construct. Remember that bracketing delimiters count nesting level.
2162 =item Substitution replacement not terminated
2164 (F) The lexer couldn't find the final delimiter of a s/// or s{}{}
2165 construct. Remember that bracketing delimiters count nesting level.
2167 =item substr outside of string
2169 (W) You tried to reference a substr() that pointed outside of a string.
2170 That is, the absolute value of the offset was larger than the length of
2171 the string. See L<perlfunc/substr>.
2173 =item suidperl is no longer needed since %s
2175 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but a
2176 version of the setuid emulator somehow got run anyway.
2180 (F) Probably means you had a syntax error. Common reasons include:
2182 A keyword is misspelled.
2183 A semicolon is missing.
2185 An opening or closing parenthesis is missing.
2186 An opening or closing brace is missing.
2187 A closing quote is missing.
2189 Often there will be another error message associated with the syntax
2190 error giving more information. (Sometimes it helps to turn on B<-w>.)
2191 The error message itself often tells you where it was in the line when
2192 it decided to give up. Sometimes the actual error is several tokens
2193 before this, because Perl is good at understanding random input.
2194 Occasionally the line number may be misleading, and once in a blue moon
2195 the only way to figure out what's triggering the error is to call
2196 C<perl -c> repeatedly, chopping away half the program each time to see
2197 if the error went away. Sort of the cybernetic version of S<20 questions>.
2199 =item syntax error at line %d: `%s' unexpected
2201 (A) You've accidentally run your script through the Bourne shell
2202 instead of Perl. Check the #! line, or manually feed your script
2205 =item System V IPC is not implemented on this machine
2207 (F) You tried to do something with a function beginning with "sem", "shm",
2208 or "msg". See L<perlfunc/semctl>, for example.
2210 =item Syswrite on closed filehandle
2212 (W) The filehandle you're writing to got itself closed sometime before now.
2213 Check your logic flow.
2215 =item tell() on unopened file
2217 (W) You tried to use the tell() function on a filehandle that was either
2218 never opened or has since been closed.
2220 =item Test on unopened file E<lt>%sE<gt>
2222 (W) You tried to invoke a file test operator on a filehandle that isn't
2223 open. Check your logic. See also L<perlfunc/-X>.
2225 =item That use of $[ is unsupported
2227 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted as
2228 a compiler directive. You may say only one of
2237 This is to prevent the problem of one module changing the array base
2238 out from under another module inadvertently. See L<perlvar/$[>.
2240 =item The %s function is unimplemented
2242 The function indicated isn't implemented on this architecture, according
2243 to the probings of Configure.
2245 =item The crypt() function is unimplemented due to excessive paranoia
2247 (F) Configure couldn't find the crypt() function on your machine,
2248 probably because your vendor didn't supply it, probably because they
2249 think the U.S. Government thinks it's a secret, or at least that they
2250 will continue to pretend that it is. And if you quote me on that, I
2253 =item The stat preceding C<-l _> wasn't an lstat
2255 (F) It makes no sense to test the current stat buffer for symbolic linkhood
2256 if the last stat that wrote to the stat buffer already went past
2257 the symlink to get to the real file. Use an actual filename instead.
2259 =item times not implemented
2261 (F) Your version of the C library apparently doesn't do times(). I suspect
2262 you're not running on Unix.
2264 =item Too few args to syscall
2266 (F) There has to be at least one argument to syscall() to specify the
2267 system call to call, silly dilly.
2269 =item Too late for "B<-T>" option
2271 (X) The #! line (or local equivalent) in a Perl script contains the
2272 B<-T> option, but Perl was not invoked with B<-T> in its command line.
2273 This is an error because, by the time Perl discovers a B<-T> in a
2274 script, it's too late to properly taint everything from the environment.
2277 If the Perl script is being executed as a command using the #!
2278 mechanism (or its local equivalent), this error can usually be fixed
2279 by editing the #! line so that the B<-T> option is a part of Perl's
2280 first argument: e.g. change C<perl -n -T> to C<perl -T -n>.
2282 If the Perl script is being executed as C<perl scriptname>, then the
2283 B<-T> option must appear on the command line: C<perl -T scriptname>.
2285 =item Too late for "-%s" option
2287 (X) The #! line (or local equivalent) in a Perl script contains the
2288 B<-M> or B<-m> option. This is an error because B<-M> and B<-m> options
2289 are not intended for use inside scripts. Use the C<use> pragma instead.
2295 (A) You've accidentally run your script through B<csh> instead
2296 of Perl. Check the #! line, or manually feed your script into
2299 =item Too many args to syscall
2301 (F) Perl supports a maximum of only 14 args to syscall().
2303 =item Too many arguments for %s
2305 (F) The function requires fewer arguments than you specified.
2307 =item trailing \ in regexp
2309 (F) The regular expression ends with an unbackslashed backslash. Backslash
2312 =item Translation pattern not terminated
2314 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
2317 =item Translation replacement not terminated
2319 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
2322 =item truncate not implemented
2324 (F) Your machine doesn't implement a file truncation mechanism that
2325 Configure knows about.
2327 =item Type of arg %d to %s must be %s (not %s)
2329 (F) This function requires the argument in that position to be of a
2330 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
2331 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
2332 {EXPR} forms as an explicit dereference. See L<perlref>.
2334 =item umask: argument is missing initial 0
2336 (W) A umask of 222 is incorrect. It should be 0222, because octal literals
2337 always start with 0 in Perl, as in C.
2339 =item Unable to create sub named "%s"
2341 (F) You attempted to create or access a subroutine with an illegal name.
2343 =item Unbalanced context: %d more PUSHes than POPs
2345 (W) The exit code detected an internal inconsistency in how many execution
2346 contexts were entered and left.
2348 =item Unbalanced saves: %d more saves than restores
2350 (W) The exit code detected an internal inconsistency in how many
2351 values were temporarily localized.
2353 =item Unbalanced scopes: %d more ENTERs than LEAVEs
2355 (W) The exit code detected an internal inconsistency in how many blocks
2356 were entered and left.
2358 =item Unbalanced tmps: %d more allocs than frees
2360 (W) The exit code detected an internal inconsistency in how many mortal
2361 scalars were allocated and freed.
2363 =item Undefined format "%s" called
2365 (F) The format indicated doesn't seem to exist. Perhaps it's really in
2366 another package? See L<perlform>.
2368 =item Undefined sort subroutine "%s" called
2370 (F) The sort comparison routine specified doesn't seem to exist. Perhaps
2371 it's in a different package? See L<perlfunc/sort>.
2373 =item Undefined subroutine &%s called
2375 (F) The subroutine indicated hasn't been defined, or if it was, it
2376 has since been undefined.
2378 =item Undefined subroutine called
2380 (F) The anonymous subroutine you're trying to call hasn't been defined,
2381 or if it was, it has since been undefined.
2383 =item Undefined subroutine in sort
2385 (F) The sort comparison routine specified is declared but doesn't seem to
2386 have been defined yet. See L<perlfunc/sort>.
2388 =item Undefined top format "%s" called
2390 (F) The format indicated doesn't seem to exist. Perhaps it's really in
2391 another package? See L<perlform>.
2393 =item unexec of %s into %s failed!
2395 (F) The unexec() routine failed for some reason. See your local FSF
2396 representative, who probably put it there in the first place.
2398 =item Unknown BYTEORDER
2400 (F) There are no byte-swapping functions for a machine with this byte order.
2402 =item unmatched () in regexp
2404 (F) Unbackslashed parentheses must always be balanced in regular
2405 expressions. If you're a vi user, the % key is valuable for finding
2406 the matching parenthesis. See L<perlre>.
2408 =item Unmatched right bracket
2410 (F) The lexer counted more closing curly brackets (braces) than opening
2411 ones, so you're probably missing an opening bracket. As a general
2412 rule, you'll find the missing one (so to speak) near the place you were
2415 =item unmatched [] in regexp
2417 (F) The brackets around a character class must match. If you wish to
2418 include a closing bracket in a character class, backslash it or put it first.
2421 =item Unquoted string "%s" may clash with future reserved word
2423 (W) You used a bareword that might someday be claimed as a reserved word.
2424 It's best to put such a word in quotes, or capitalize it somehow, or insert
2425 an underbar into it. You might also declare it as a subroutine.
2427 =item Unrecognized character %s
2429 (F) The Perl parser has no idea what to do with the specified character
2430 in your Perl script (or eval). Perhaps you tried to run a compressed
2431 script, a binary program, or a directory as a Perl program.
2433 =item Unrecognized signal name "%s"
2435 (F) You specified a signal name to the kill() function that was not recognized.
2436 Say C<kill -l> in your shell to see the valid signal names on your system.
2438 =item Unrecognized switch: -%s
2440 (F) You specified an illegal option to Perl. Don't do that.
2441 (If you think you didn't do that, check the #! line to see if it's
2442 supplying the bad switch on your behalf.)
2444 =item Unsuccessful %s on filename containing newline
2446 (W) A file operation was attempted on a filename, and that operation
2447 failed, PROBABLY because the filename contained a newline, PROBABLY
2448 because you forgot to chop() or chomp() it off. See L<perlfunc/chomp>.
2450 =item Unsupported directory function "%s" called
2452 (F) Your machine doesn't support opendir() and readdir().
2454 =item Unsupported function fork
2456 (F) Your version of executable does not support forking.
2458 Note that under some systems, like OS/2, there may be different flavors of
2459 Perl executables, some of which may support fork, some not. Try changing
2460 the name you call Perl by to C<perl_>, C<perl__>, and so on.
2462 =item Unsupported function %s
2464 (F) This machines doesn't implement the indicated function, apparently.
2465 At least, Configure doesn't think so.
2467 =item Unsupported socket function "%s" called
2469 (F) Your machine doesn't support the Berkeley socket mechanism, or at
2470 least that's what Configure thought.
2472 =item Unterminated E<lt>E<gt> operator
2474 (F) The lexer saw a left angle bracket in a place where it was expecting
2475 a term, so it's looking for the corresponding right angle bracket, and not
2476 finding it. Chances are you left some needed parentheses out earlier in
2477 the line, and you really meant a "less than".
2479 =item Use of "$$<digit>" to mean "${$}<digit>" is deprecated
2481 (D) Perl versions before 5.004 misinterpreted any type marker followed
2482 by "$" and a digit. For example, "$$0" was incorrectly taken to mean
2483 "${$}0" instead of "${$0}". This bug is (mostly) fixed in Perl 5.004.
2485 However, the developers of Perl 5.004 could not fix this bug completely,
2486 because at least two widely-used modules depend on the old meaning of
2487 "$$0" in a string. So Perl 5.004 still interprets "$$<digit>" in the
2488 old (broken) way inside strings; but it generates this message as a
2489 warning. And in Perl 5.005, this special treatment will cease.
2491 =item Use of $# is deprecated
2493 (D) This was an ill-advised attempt to emulate a poorly defined B<awk> feature.
2494 Use an explicit printf() or sprintf() instead.
2496 =item Use of $* is deprecated
2498 (D) This variable magically turned on multi-line pattern matching, both for
2499 you and for any luckless subroutine that you happen to call. You should
2500 use the new C<//m> and C<//s> modifiers now to do that without the dangerous
2501 action-at-a-distance effects of C<$*>.
2503 =item Use of %s in printf format not supported
2505 (F) You attempted to use a feature of printf that is accessible from
2506 only C. This usually means there's a better way to do it in Perl.
2508 =item Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated
2510 (D) You are now encouraged to use the explicitly quoted form if you
2511 wish to use an empty line as the terminator of the here-document.
2513 =item Use of implicit split to @_ is deprecated
2515 (D) It makes a lot of work for the compiler when you clobber a
2516 subroutine's argument list, so it's better if you assign the results of
2517 a split() explicitly to an array (or list).
2519 =item Use of inherited AUTOLOAD for non-method %s() is deprecated
2521 (D) As an (ahem) accidental feature, C<AUTOLOAD> subroutines are looked
2522 up as methods (using the C<@ISA> hierarchy) even when the subroutines to
2523 be autoloaded were called as plain functions (e.g. C<Foo::bar()>), not
2524 as methods (e.g. C<Foo->bar()> or C<$obj->bar()>).
2526 This bug will be rectified in Perl 5.005, which will use method lookup
2527 only for methods' C<AUTOLOAD>s. However, there is a significant base
2528 of existing code that may be using the old behavior. So, as an
2529 interim step, Perl 5.004 issues an optional warning when non-methods
2530 use inherited C<AUTOLOAD>s.
2532 The simple rule is: Inheritance will not work when autoloading
2533 non-methods. The simple fix for old code is: In any module that used to
2534 depend on inheriting C<AUTOLOAD> for non-methods from a base class named
2535 C<BaseClass>, execute C<*AUTOLOAD = \&BaseClass::AUTOLOAD> during startup.
2537 =item Use of %s is deprecated
2539 (D) The construct indicated is no longer recommended for use, generally
2540 because there's a better way to do it, and also because the old way has
2543 =item Use of uninitialized value
2545 (W) An undefined value was used as if it were already defined. It was
2546 interpreted as a "" or a 0, but maybe it was a mistake. To suppress this
2547 warning assign an initial value to your variables.
2549 =item Useless use of %s in void context
2551 (W) You did something without a side effect in a context that does nothing
2552 with the return value, such as a statement that doesn't return a value
2553 from a block, or the left side of a scalar comma operator. Very often
2554 this points not to stupidity on your part, but a failure of Perl to parse
2555 your program the way you thought it would. For example, you'd get this
2556 if you mixed up your C precedence with Python precedence and said
2560 when you meant to say
2562 ($one, $two) = (1, 2);
2564 Another common error is to use ordinary parentheses to construct a list
2565 reference when you should be using square or curly brackets, for
2570 when you should have said
2574 The square brackets explicitly turn a list value into a scalar value,
2575 while parentheses do not. So when a parenthesized list is evaluated in
2576 a scalar context, the comma is treated like C's comma operator, which
2577 throws away the left argument, which is not what you want. See
2578 L<perlref> for more on this.
2580 =item untie attempted while %d inner references still exist
2582 (W) A copy of the object returned from C<tie> (or C<tied>) was still
2583 valid when C<untie> was called.
2585 =item Value of %s can be "0"; test with defined()
2587 (W) In a conditional expression, you used <HANDLE>, <*> (glob), C<each()>,
2588 or C<readdir()> as a boolean value. Each of these constructs can return a
2589 value of "0"; that would make the conditional expression false, which is
2590 probably not what you intended. When using these constructs in conditional
2591 expressions, test their values with the C<defined> operator.
2593 =item Variable "%s" is not imported%s
2595 (F) While "use strict" in effect, you referred to a global variable
2596 that you apparently thought was imported from another module, because
2597 something else of the same name (usually a subroutine) is exported
2598 by that module. It usually means you put the wrong funny character
2599 on the front of your variable.
2601 =item Variable "%s" may be unavailable
2603 (W) An inner (nested) I<anonymous> subroutine is inside a I<named>
2604 subroutine, and outside that is another subroutine; and the anonymous
2605 (innermost) subroutine is referencing a lexical variable defined in
2606 the outermost subroutine. For example:
2608 sub outermost { my $a; sub middle { sub { $a } } }
2610 If the anonymous subroutine is called or referenced (directly or
2611 indirectly) from the outermost subroutine, it will share the variable
2612 as you would expect. But if the anonymous subroutine is called or
2613 referenced when the outermost subroutine is not active, it will see
2614 the value of the shared variable as it was before and during the
2615 *first* call to the outermost subroutine, which is probably not what
2618 In these circumstances, it is usually best to make the middle
2619 subroutine anonymous, using the C<sub {}> syntax. Perl has specific
2620 support for shared variables in nested anonymous subroutines; a named
2621 subroutine in between interferes with this feature.
2623 =item Variable "%s" will not stay shared
2625 (W) An inner (nested) I<named> subroutine is referencing a lexical
2626 variable defined in an outer subroutine.
2628 When the inner subroutine is called, it will probably see the value of
2629 the outer subroutine's variable as it was before and during the
2630 *first* call to the outer subroutine; in this case, after the first
2631 call to the outer subroutine is complete, the inner and outer
2632 subroutines will no longer share a common value for the variable. In
2633 other words, the variable will no longer be shared.
2635 Furthermore, if the outer subroutine is anonymous and references a
2636 lexical variable outside itself, then the outer and inner subroutines
2637 will I<never> share the given variable.
2639 This problem can usually be solved by making the inner subroutine
2640 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
2641 reference variables in outer subroutines are called or referenced,
2642 they are automatically rebound to the current values of such
2645 =item Variable syntax
2647 (A) You've accidentally run your script through B<csh> instead
2648 of Perl. Check the #! line, or manually feed your script into
2651 =item Warning: something's wrong
2653 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
2654 you called it with no args and C<$_> was empty.
2656 =item Warning: unable to close filehandle %s properly
2658 (S) The implicit close() done by an open() got an error indication on the
2659 close(). This usually indicates your file system ran out of disk space.
2661 =item Warning: Use of "%s" without parentheses is ambiguous
2663 (S) You wrote a unary operator followed by something that looks like a
2664 binary operator that could also have been interpreted as a term or
2665 unary operator. For instance, if you know that the rand function
2666 has a default argument of 1.0, and you write
2670 you may THINK you wrote the same thing as
2674 but in actual fact, you got
2678 So put in parentheses to say what you really mean.
2680 =item Write on closed filehandle
2682 (W) The filehandle you're writing to got itself closed sometime before now.
2683 Check your logic flow.
2685 =item X outside of string
2687 (F) You had a pack template that specified a relative position before
2688 the beginning of the string being unpacked. See L<perlfunc/pack>.
2690 =item x outside of string
2692 (F) You had a pack template that specified a relative position after
2693 the end of the string being unpacked. See L<perlfunc/pack>.
2695 =item Xsub "%s" called in sort
2697 (F) The use of an external subroutine as a sort comparison is not yet supported.
2699 =item Xsub called in sort
2701 (F) The use of an external subroutine as a sort comparison is not yet supported.
2703 =item You can't use C<-l> on a filehandle
2705 (F) A filehandle represents an opened file, and when you opened the file it
2706 already went past any symlink you are presumably trying to look for.
2707 Use a filename instead.
2709 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
2711 (F) And you probably never will, because you probably don't have the
2712 sources to your kernel, and your vendor probably doesn't give a rip
2713 about what you want. Your best bet is to use the wrapsuid script in
2714 the eg directory to put a setuid C wrapper around your script.
2716 =item You need to quote "%s"
2718 (W) You assigned a bareword as a signal handler name. Unfortunately, you
2719 already have a subroutine of that name declared, which means that Perl 5
2720 will try to call the subroutine when the assignment is executed, which is
2721 probably not what you want. (If it IS what you want, put an & in front.)
2723 =item [gs]etsockopt() on closed fd
2725 (W) You tried to get or set a socket option on a closed socket.
2726 Did you forget to check the return value of your socket() call?
2727 See L<perlfunc/getsockopt>.
2729 =item \1 better written as $1
2731 (W) Outside of patterns, backreferences live on as variables. The use
2732 of backslashes is grandfathered on the right-hand side of a
2733 substitution, but stylistically it's better to use the variable form
2734 because other Perl programmers will expect it, and it works better
2735 if there are more than 9 backreferences.
2737 =item '|' and 'E<lt>' may not both be specified on command line
2739 (F) An error peculiar to VMS. Perl does its own command line redirection, and
2740 found that STDIN was a pipe, and that you also tried to redirect STDIN using
2741 'E<lt>'. Only one STDIN stream to a customer, please.
2743 =item '|' and 'E<gt>' may not both be specified on command line
2745 (F) An error peculiar to VMS. Perl does its own command line redirection, and
2746 thinks you tried to redirect stdout both to a file and into a pipe to another
2747 command. You need to choose one or the other, though nothing's stopping you
2748 from piping into a program or Perl script which 'splits' output into two
2751 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
2758 =item Got an error from DosAllocMem
2760 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2761 version of Perl, and this should not happen anyway.
2763 =item Malformed PERLLIB_PREFIX
2765 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2773 with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix
2774 of a builtin library search path, prefix2 is substituted. The error
2775 may appear if components are not found, or are too long. See
2776 "PERLLIB_PREFIX" in F<README.os2>.
2778 =item PERL_SH_DIR too long
2780 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2781 C<sh>-shell in. See "PERL_SH_DIR" in F<README.os2>.
2783 =item Process terminated by SIG%s
2785 (W) This is a standard message issued by OS/2 applications, while *nix
2786 applications die in silence. It is considered a feature of the OS/2
2787 port. One can easily disable this by appropriate sighandlers, see
2788 L<perlipc/"Signals">. See also "Process terminated by SIGTERM/SIGINT"