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 (non-trappable).
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 MSDOS 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 non-existent 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 BEGIN failed--compilation aborted
339 (F) An untrapped exception was raised while executing a BEGIN subroutine.
340 Compilation stops immediately and the interpreter is exited.
342 =item BEGIN not safe after errors--compilation aborted
344 (F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
345 implies a C<BEGIN {}>) after one or more compilation errors had
346 already occurred. Since the intended environment for the C<BEGIN {}>
347 could not be guaranteed (due to the errors), and since subsequent code
348 likely depends on its correct operation, Perl just gave up.
350 =item bind() on closed fd
352 (W) You tried to do a bind on a closed socket. Did you forget to check
353 the return value of your socket() call? See L<perlfunc/bind>.
355 =item Bizarre copy of %s in %s
357 (P) Perl detected an attempt to copy an internal value that is not copiable.
359 =item Callback called exit
361 (F) A subroutine invoked from an external package via perl_call_sv()
362 exited by calling exit.
364 =item Can't "goto" outside a block
366 (F) A "goto" statement was executed to jump out of what might look
367 like a block, except that it isn't a proper block. This usually
368 occurs if you tried to jump out of a sort() block or subroutine, which
369 is a no-no. See L<perlfunc/goto>.
371 =item Can't "last" outside a block
373 (F) A "last" statement was executed to break out of the current block,
374 except that there's this itty bitty problem called there isn't a
375 current block. Note that an "if" or "else" block doesn't count as a
376 "loopish" block, as doesn't a block given to sort(). You can usually double
377 the curlies to get the same effect though, because the inner curlies
378 will be considered a block that loops once. See L<perlfunc/last>.
380 =item Can't "next" outside a block
382 (F) A "next" statement was executed to reiterate the current block, but
383 there isn't a current block. Note that an "if" or "else" block doesn't
384 count as a "loopish" block, as doesn't a block given to sort(). You can
385 usually double the curlies to get the same effect though, because the inner
386 curlies will be considered a block that loops once. See L<perlfunc/last>.
388 =item Can't "redo" outside a block
390 (F) A "redo" statement was executed to restart the current block, but
391 there isn't a current block. Note that an "if" or "else" block doesn't
392 count as a "loopish" block, as doesn't a block given to sort(). You can
393 usually double the curlies to get the same effect though, because the inner
394 curlies will be considered a block that loops once. See L<perlfunc/last>.
396 =item Can't bless non-reference value
398 (F) Only hard references may be blessed. This is how Perl "enforces"
399 encapsulation of objects. See L<perlobj>.
401 =item Can't break at that line
403 (S) A warning intended for while running within the debugger, indicating
404 the line number specified wasn't the location of a statement that could
407 =item Can't call method "%s" in empty package "%s"
409 (F) You called a method correctly, and it correctly indicated a package
410 functioning as a class, but that package doesn't have ANYTHING defined
411 in it, let alone methods. See L<perlobj>.
413 =item Can't call method "%s" on unblessed reference
415 (F) A method call must know what package it's supposed to run in. It
416 ordinarily finds this out from the object reference you supply, but
417 you didn't supply an object reference in this case. A reference isn't
418 an object reference until it has been blessed. See L<perlobj>.
420 =item Can't call method "%s" without a package or object reference
422 (F) You used the syntax of a method call, but the slot filled by the
423 object reference or package name contains an expression that returns
424 neither an object reference nor a package name. (Perhaps it's null?)
425 Something like this will reproduce the error:
428 process $BADREF 1,2,3;
429 $BADREF->process(1,2,3);
431 =item Can't chdir to %s
433 (F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
434 that you can chdir to, possibly because it doesn't exist.
436 =item Can't coerce %s to integer in %s
438 (F) Certain types of SVs, in particular real symbol table entries
439 (typeglobs), can't be forced to stop being what they are. So you can't
449 but then $foo no longer contains a glob.
451 =item Can't coerce %s to number in %s
453 (F) Certain types of SVs, in particular real symbol table entries
454 (typeglobs), can't be forced to stop being what they are.
456 =item Can't coerce %s to string in %s
458 (F) Certain types of SVs, in particular real symbol table entries
459 (typeglobs), can't be forced to stop being what they are.
461 =item Can't create pipe mailbox
463 (P) An error peculiar to VMS. The process is suffering from exhausted quotas
464 or other plumbing problems.
466 =item Can't declare %s in my
468 (F) Only scalar, array, and hash variables may be declared as lexical variables.
469 They must have ordinary identifiers as names.
471 =item Can't do inplace edit on %s: %s
473 (S) The creation of the new file failed for the indicated reason.
475 =item Can't do in-place edit without backup
477 (F) You're on a system such as MSDOS that gets confused if you try reading
478 from a deleted (but still opened) file. You have to say B<-i>C<.bak>, or some
481 =item Can't do inplace edit: %s E<gt> 14 characters
483 (S) There isn't enough room in the filename to make a backup name for the file.
485 =item Can't do inplace edit: %s is not a regular file
487 (S) You tried to use the B<-i> switch on a special file, such as a file in
488 /dev, or a FIFO. The file was ignored.
490 =item Can't do setegid!
492 (P) The setegid() call failed for some reason in the setuid emulator
495 =item Can't do seteuid!
497 (P) The setuid emulator of suidperl failed for some reason.
499 =item Can't do setuid
501 (F) This typically means that ordinary perl tried to exec suidperl to
502 do setuid emulation, but couldn't exec it. It looks for a name of the
503 form sperl5.000 in the same directory that the perl executable resides
504 under the name perl5.000, typically /usr/local/bin on Unix machines.
505 If the file is there, check the execute permissions. If it isn't, ask
506 your sysadmin why he and/or she removed it.
508 =item Can't do waitpid with flags
510 (F) This machine doesn't have either waitpid() or wait4(), so only waitpid()
511 without flags is emulated.
513 =item Can't do {n,m} with n E<gt> m
515 (F) Minima must be less than or equal to maxima. If you really want
516 your regexp to match something 0 times, just put {0}. See L<perlre>.
518 =item Can't emulate -%s on #! line
520 (F) The #! line specifies a switch that doesn't make sense at this point.
521 For example, it'd be kind of silly to put a B<-x> on the #! line.
523 =item Can't exec "%s": %s
525 (W) An system(), exec(), or piped open call could not execute the named
526 program for the indicated reason. Typical reasons include: the permissions
527 were wrong on the file, the file wasn't found in C<$ENV{PATH}>, the
528 executable in question was compiled for another architecture, or the
529 #! line in a script points to an interpreter that can't be run for
530 similar reasons. (Or maybe your system doesn't support #! at all.)
534 (F) Perl was trying to execute the indicated program for you because that's
535 what the #! line said. If that's not what you wanted, you may need to
536 mention "perl" on the #! line somewhere.
538 =item Can't execute %s
540 (F) You used the B<-S> switch, but the script to execute could not be found
541 in the PATH, or at least not with the correct permissions.
543 =item Can't find label %s
545 (F) You said to goto a label that isn't mentioned anywhere that it's possible
546 for us to go to. See L<perlfunc/goto>.
548 =item Can't find string terminator %s anywhere before EOF
550 (F) Perl strings can stretch over multiple lines. This message means that
551 the closing delimiter was omitted. Because bracketed quotes count nesting
552 levels, the following is missing its final parenthesis:
554 print q(The character '(' starts a side comment.)
558 (F) A fatal error occurred while trying to fork while opening a pipeline.
560 =item Unsupported function fork
562 (F) Your version of executable does not support forking.
564 Note that under some systems, like OS/2, there may be different flavors of
565 Perl executables, some of which may support fork, some not. Try changing
566 the name you call Perl by to C<perl_>, C<perl__>, and so on.
568 =item Can't get filespec - stale stat buffer?
570 (S) A warning peculiar to VMS. This arises because of the difference between
571 access checks under VMS and under the Unix model Perl assumes. Under VMS,
572 access checks are done by filename, rather than by bits in the stat buffer, so
573 that ACLs and other protections can be taken into account. Unfortunately, Perl
574 assumes that the stat buffer contains all the necessary information, and passes
575 it, instead of the filespec, to the access checking routine. It will try to
576 retrieve the filespec using the device name and FID present in the stat buffer,
577 but this works only if you haven't made a subsequent call to the CRTL stat()
578 routine, because the device name is overwritten with each call. If this warning
579 appears, the name lookup failed, and the access checking routine gave up and
580 returned FALSE, just to be conservative. (Note: The access checking routine
581 knows about the Perl C<stat> operator and file tests, so you shouldn't ever
582 see this warning in response to a Perl command; it arises only if some internal
583 code takes stat buffers lightly.)
585 =item Can't get pipe mailbox device name
587 (P) An error peculiar to VMS. After creating a mailbox to act as a pipe, Perl
588 can't retrieve its name for later use.
590 =item Can't get SYSGEN parameter value for MAXBUF
592 (P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
593 mailbox buffers to be, and didn't get an answer.
595 =item Can't goto subroutine outside a subroutine
597 (F) The deeply magical "goto subroutine" call can only replace one subroutine
598 call for another. It can't manufacture one out of whole cloth. In general
599 you should be calling it out of only an AUTOLOAD routine anyway. See
602 =item Can't localize a reference
604 (F) You said something like C<local $$ref>, which is not allowed because
605 the compiler can't determine whether $ref will end up pointing to anything
606 with a symbol table entry, and a symbol table entry is necessary to
609 =item Can't localize lexical variable %s
611 (F) You used local on a variable name that was previously declared as a
612 lexical variable using "my". This is not allowed. If you want to
613 localize a package variable of the same name, qualify it with the
616 =item Can't locate %s in @INC
618 (F) You said to do (or require, or use) a file that couldn't be found
619 in any of the libraries mentioned in @INC. Perhaps you need to set
620 the PERL5LIB environment variable to say where the extra library is,
621 or maybe the script needs to add the library name to @INC. Or maybe
622 you just misspelled the name of the file. See L<perlfunc/require>.
624 =item Can't locate object method "%s" via package "%s"
626 (F) You called a method correctly, and it correctly indicated a package
627 functioning as a class, but that package doesn't define that particular
628 method, nor does any of its base classes. See L<perlobj>.
630 =item Can't locate package %s for @%s::ISA
632 (W) The @ISA array contained the name of another package that doesn't seem
637 (F) The mktemp() routine failed for some reason while trying to process
638 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
640 =item Can't modify %s in %s
642 (F) You aren't allowed to assign to the item indicated, or otherwise try to
643 change it, such as with an auto-increment.
645 =item Can't modify non-existent substring
647 (P) The internal routine that does assignment to a substr() was handed
650 =item Can't msgrcv to read-only var
652 (F) The target of a msgrcv must be modifiable to be used as a receive
655 =item Can't open %s: %s
657 (S) An in-place edit couldn't open the original file for the indicated reason.
658 Usually this is because you don't have read permission for the file.
660 =item Can't open bidirectional pipe
662 (W) You tried to say C<open(CMD, "|cmd|")>, which is not supported. You can
663 try any of several modules in the Perl library to do this, such as
664 IPC::Open2. Alternately, direct the pipe's output to a file using "E<gt>",
665 and then read it in under a different file handle.
667 =item Can't open error file %s as stderr
669 (F) An error peculiar to VMS. Perl does its own command line redirection, and
670 couldn't open the file specified after '2E<gt>' or '2E<gt>E<gt>' on the
671 command line for writing.
673 =item Can't open input file %s as stdin
675 (F) An error peculiar to VMS. Perl does its own command line redirection, and
676 couldn't open the file specified after 'E<lt>' on the command line for reading.
678 =item Can't open output file %s as stdout
680 (F) An error peculiar to VMS. Perl does its own command line redirection, and
681 couldn't open the file specified after 'E<gt>' or 'E<gt>E<gt>' on the command
684 =item Can't open output pipe (name: %s)
686 (P) An error peculiar to VMS. Perl does its own command line redirection, and
687 couldn't open the pipe into which to send data destined for stdout.
689 =item Can't open perl script "%s": %s
691 (F) The script you specified can't be opened for the indicated reason.
693 =item Can't rename %s to %s: %s, skipping file
695 (S) The rename done by the B<-i> switch failed for some reason, probably because
696 you don't have write permission to the directory.
698 =item Can't reopen input pipe (name: %s) in binary mode
700 (P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried to
701 reopen it to accept binary data. Alas, it failed.
703 =item Can't reswap uid and euid
705 (P) The setreuid() call failed for some reason in the setuid emulator
708 =item Can't return outside a subroutine
710 (F) The return statement was executed in mainline code, that is, where
711 there was no subroutine call to return out of. See L<perlsub>.
713 =item Can't stat script "%s"
715 (P) For some reason you can't fstat() the script even though you have
716 it open already. Bizarre.
718 =item Can't swap uid and euid
720 (P) The setreuid() call failed for some reason in the setuid emulator
723 =item Can't take log of %g
725 (F) Logarithms are defined on only positive real numbers.
727 =item Can't take sqrt of %g
729 (F) For ordinary real numbers, you can't take the square root of a
730 negative number. There's a Complex package available for Perl, though,
731 if you really want to do that.
733 =item Can't undef active subroutine
735 (F) You can't undefine a routine that's currently running. You can,
736 however, redefine it while it's running, and you can even undef the
737 redefined subroutine while the old routine is running. Go figure.
741 (F) You tried to unshift an "unreal" array that can't be unshifted, such
742 as the main Perl stack.
744 =item Can't upgrade that kind of scalar
746 (P) The internal sv_upgrade routine adds "members" to an SV, making
747 it into a more specialized kind of SV. The top several SV types are
748 so specialized, however, that they cannot be interconverted. This
749 message indicates that such a conversion was attempted.
751 =item Can't upgrade to undef
753 (P) The undefined SV is the bottom of the totem pole, in the scheme
754 of upgradability. Upgrading to undef indicates an error in the
755 code calling sv_upgrade.
757 =item Can't use "my %s" in sort comparison
759 (F) The global variables $a and $b are reserved for sort comparisons.
760 You mentioned $a or $b in the same line as the E<lt>=E<gt> or cmp operator,
761 and the variable had earlier been declared as a lexical variable.
762 Either qualify the sort variable with the package name, or rename the
765 =item Can't use %s for loop variable
767 (F) Only a simple scalar variable may be used as a loop variable on a foreach.
769 =item Can't use %s ref as %s ref
771 (F) You've mixed up your reference types. You have to dereference a
772 reference of the type needed. You can use the ref() function to
773 test the type of the reference, if need be.
775 =item Can't use \1 to mean $1 in expression
777 (W) In an ordinary expression, backslash is a unary operator that creates
778 a reference to its argument. The use of backslash to indicate a backreference
779 to a matched substring is valid only as part of a regular expression pattern.
780 Trying to do this in ordinary Perl code produces a value that prints
781 out looking like SCALAR(0xdecaf). Use the $1 form instead.
783 =item Can't use bareword ("%s") as %s ref while \"strict refs\" in use
785 (F) Only hard references are allowed by "strict refs". Symbolic references
786 are disallowed. See L<perlref>.
788 =item Can't use string ("%s") as %s ref while "strict refs" in use
790 (F) Only hard references are allowed by "strict refs". Symbolic references
791 are disallowed. See L<perlref>.
793 =item Can't use an undefined value as %s reference
795 (F) A value used as either a hard reference or a symbolic reference must
796 be a defined value. This helps to de-lurk some insidious errors.
798 =item Can't use global %s in "my"
800 (F) You tried to declare a magical variable as a lexical variable. This is
801 not allowed, because the magic can be tied to only one location (namely
802 the global variable) and it would be incredibly confusing to have
803 variables in your program that looked like magical variables but
806 =item Can't use subscript on %s
808 (F) The compiler tried to interpret a bracketed expression as a
809 subscript. But to the left of the brackets was an expression that
810 didn't look like an array reference, or anything else subscriptable.
812 =item Can't write to temp file for B<-e>: %s
814 (F) The write routine failed for some reason while trying to process
815 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
817 =item Can't x= to read-only value
819 (F) You tried to repeat a constant value (often the undefined value) with
820 an assignment operator, which implies modifying the value itself.
821 Perhaps you need to copy the value to a temporary, and repeat that.
823 =item Cannot open temporary file
825 (F) The create routine failed for some reason while trying to process
826 a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
828 =item Cannot resolve method `%s' overloading `%s' in package `%s'
830 (F|P) Error resolving overloading specified by a method name (as
831 opposed to a subroutine reference): no such method callable via the
832 package. If method name is C<???>, this is an internal error.
834 =item chmod: mode argument is missing initial 0
836 (W) A novice will sometimes say
840 not realizing that 777 will be interpreted as a decimal number, equivalent
841 to 01411. Octal constants are introduced with a leading 0 in Perl, as in C.
843 =item Close on unopened file E<lt>%sE<gt>
845 (W) You tried to close a filehandle that was never opened.
847 =item connect() on closed fd
849 (W) You tried to do a connect on a closed socket. Did you forget to check
850 the return value of your socket() call? See L<perlfunc/connect>.
852 =item Constant subroutine %s redefined
854 (S) You redefined a subroutine which had previously been eligible for
855 inlining. See L<perlsub/"Constant Functions"> for commentary and
858 =item Constant subroutine %s undefined
860 (S) You undefined a subroutine which had previously been eligible for
861 inlining. See L<perlsub/"Constant Functions"> for commentary and
864 =item Copy method did not return a reference
866 (F) The method which overloads "=" is buggy. See L<overload/Copy Constructor>.
868 =item Corrupt malloc ptr 0x%lx at 0x%lx
870 (P) The malloc package that comes with Perl had an internal failure.
872 =item corrupted regexp pointers
874 (P) The regular expression engine got confused by what the regular
875 expression compiler gave it.
877 =item corrupted regexp program
879 (P) The regular expression engine got passed a regexp program without
880 a valid magic number.
882 =item Deep recursion on subroutine "%s"
884 (W) This subroutine has called itself (directly or indirectly) 100
885 times than it has returned. This probably indicates an infinite
886 recursion, unless you're writing strange benchmark programs, in which
887 case it indicates something else.
889 =item Did you mean &%s instead?
891 (W) You probably referred to an imported subroutine &FOO as $FOO or some such.
893 =item Did you mean $ or @ instead of %?
895 (W) You probably said %hash{$key} when you meant $hash{$key} or @hash{@keys}.
896 On the other hand, maybe you just meant %hash and got carried away.
900 (F) You passed die() an empty string (the equivalent of C<die "">) or
901 you called it with no args and both C<$@> and C<$_> were empty.
903 =item Do you need to pre-declare %s?
905 (S) This is an educated guess made in conjunction with the message "%s
906 found where operator expected". It often means a subroutine or module
907 name is being referenced that hasn't been declared yet. This may be
908 because of ordering problems in your file, or because of a missing
909 "sub", "package", "require", or "use" statement. If you're
910 referencing something that isn't defined yet, you don't actually have
911 to define the subroutine or package before the current location. You
912 can use an empty "sub foo;" or "package FOO;" to enter a "forward"
915 =item Don't know how to handle magic of type '%s'
917 (P) The internal handling of magical variables has been cursed.
919 =item do_study: out of memory
921 (P) This should have been caught by safemalloc() instead.
923 =item Duplicate free() ignored
925 (S) An internal routine called free() on something that had already
928 =item elseif should be elsif
930 (S) There is no keyword "elseif" in Perl because Larry thinks it's
931 ugly. Your code will be interpreted as an attempt to call a method
932 named "elseif" for the class returned by the following block. This is
933 unlikely to be what you want.
935 =item END failed--cleanup aborted
937 (F) An untrapped exception was raised while executing an END subroutine.
938 The interpreter is immediately exited.
940 =item Error converting file specification %s
942 (F) An error peculiar to VMS. Because Perl may have to deal with file
943 specifications in either VMS or Unix syntax, it converts them to a
944 single form when it must operate on them directly. Either you've
945 passed an invalid file specification to Perl, or you've found a
946 case the conversion routines don't handle. Drat.
948 =item Execution of %s aborted due to compilation errors
950 (F) The final summary message when a Perl compilation fails.
952 =item Exiting eval via %s
954 (W) You are exiting an eval by unconventional means, such as
955 a goto, or a loop control statement.
957 =item Exiting pseudo-block via %s
959 (W) You are exiting a rather special block construct (like a sort block or
960 subroutine) by unconventional means, such as a goto, or a loop control
961 statement. See L<perlfunc/sort>.
963 =item Exiting subroutine via %s
965 (W) You are exiting a subroutine by unconventional means, such as
966 a goto, or a loop control statement.
968 =item Exiting substitution via %s
970 (W) You are exiting a substitution by unconventional means, such as
971 a return, a goto, or a loop control statement.
973 =item Fatal VMS error at %s, line %d
975 (P) An error peculiar to VMS. Something untoward happened in a VMS system
976 service or RTL routine; Perl's exit status should provide more details. The
977 filename in "at %s" and the line number in "line %d" tell you which section of
978 the Perl source code is distressed.
980 =item fcntl is not implemented
982 (F) Your machine apparently doesn't implement fcntl(). What is this, a
985 =item Filehandle %s never opened
987 (W) An I/O operation was attempted on a filehandle that was never initialized.
988 You need to do an open() or a socket() call, or call a constructor from
989 the FileHandle package.
991 =item Filehandle %s opened for only input
993 (W) You tried to write on a read-only filehandle. If you
994 intended it to be a read-write filehandle, you needed to open it with
995 "+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing. If
996 you intended only to write the file, use "E<gt>" or "E<gt>E<gt>". See
999 =item Filehandle opened for only input
1001 (W) You tried to write on a read-only filehandle. If you
1002 intended it to be a read-write filehandle, you needed to open it with
1003 "+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing. If
1004 you intended only to write the file, use "E<gt>" or "E<gt>E<gt>". See
1007 =item Final $ should be \$ or $name
1009 (F) You must now decide whether the final $ in a string was meant to be
1010 a literal dollar sign, or was meant to introduce a variable name
1011 that happens to be missing. So you have to put either the backslash or
1014 =item Final @ should be \@ or @name
1016 (F) You must now decide whether the final @ in a string was meant to be
1017 a literal "at" sign, or was meant to introduce a variable name
1018 that happens to be missing. So you have to put either the backslash or
1021 =item Format %s redefined
1023 (W) You redefined a format. To suppress this warning, say
1027 eval "format NAME =...";
1030 =item Format not terminated
1032 (F) A format must be terminated by a line with a solitary dot. Perl got
1033 to the end of your file without finding such a line.
1035 =item Found = in conditional, should be ==
1045 (or something like that).
1047 =item gdbm store returned %d, errno %d, key "%s"
1049 (S) A warning from the GDBM_File extension that a store failed.
1051 =item gethostent not implemented
1053 (F) Your C library apparently doesn't implement gethostent(), probably
1054 because if it did, it'd feel morally obligated to return every hostname
1057 =item get{sock,peer}name() on closed fd
1059 (W) You tried to get a socket or peer socket name on a closed socket.
1060 Did you forget to check the return value of your socket() call?
1062 =item getpwnam returned invalid UIC %#o for user "%s"
1064 (S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
1065 C<getpwnam> operator returned an invalid UIC.
1068 =item Glob not terminated
1070 (F) The lexer saw a left angle bracket in a place where it was expecting
1071 a term, so it's looking for the corresponding right angle bracket, and not
1072 finding it. Chances are you left some needed parentheses out earlier in
1073 the line, and you really meant a "less than".
1075 =item Global symbol "%s" requires explicit package name
1077 (F) You've said "use strict vars", which indicates that all variables
1078 must either be lexically scoped (using "my"), or explicitly qualified to
1079 say which package the global variable is in (using "::").
1081 =item goto must have label
1083 (F) Unlike with "next" or "last", you're not allowed to goto an
1084 unspecified destination. See L<perlfunc/goto>.
1086 =item Had to create %s unexpectedly
1088 (S) A routine asked for a symbol from a symbol table that ought to have
1089 existed already, but for some reason it didn't, and had to be created on
1090 an emergency basis to prevent a core dump.
1092 =item Hash %%s missing the % in argument %d of %s()
1094 (D) Really old Perl let you omit the % on hash names in some spots. This
1095 is now heavily deprecated.
1097 =item Ill-formed logical name |%s| in prime_env_iter
1099 (W) A warning peculiar to VMS. A logical name was encountered when preparing
1100 to iterate over %ENV which violates the syntactic rules governing logical
1101 names. Because it cannot be translated normally, it is skipped, and will not
1102 appear in %ENV. This may be a benign occurrence, as some software packages
1103 might directly modify logical name tables and introduce non-standard names,
1104 or it may indicate that a logical name table has been corrupted.
1106 =item Illegal character %s (carriage return)
1108 (F) A carriage return character was found in the input. This is an
1109 error, and not a warning, because carriage return characters can break
1110 here documents (e.g., C<print E<lt>E<lt>EOF;>).
1112 Under UNIX, this error is usually caused by executing Perl code --
1113 either the main program, a module, or an eval'd string -- that was
1114 transferred over a network connection from a non-UNIX system without
1115 properly converting the text file format.
1117 Under systems that use something other than '\n' to delimit lines of
1118 text, this error can also be caused by reading Perl code from a file
1119 handle that is in binary mode (as set by the C<binmode> operator).
1121 In either case, the Perl code in question will probably need to be
1122 converted with something like C<s/\x0D\x0A?/\n/g> before it can be
1125 =item Illegal division by zero
1127 (F) You tried to divide a number by 0. Either something was wrong in your
1128 logic, or you need to put a conditional in to guard against meaningless input.
1130 =item Illegal modulus zero
1132 (F) You tried to divide a number by 0 to get the remainder. Most numbers
1133 don't take to this kindly.
1135 =item Illegal octal digit
1137 (F) You used an 8 or 9 in a octal number.
1139 =item Illegal octal digit ignored
1141 (W) You may have tried to use an 8 or 9 in a octal number. Interpretation
1142 of the octal number stopped before the 8 or 9.
1144 =item In string, @%s now must be written as \@%s
1146 (F) It used to be that Perl would try to guess whether you wanted an
1147 array interpolated or a literal @. It did this when the string was first
1148 used at runtime. Now strings are parsed at compile time, and ambiguous
1149 instances of @ must be disambiguated, either by prepending a backslash to
1150 indicate a literal, or by declaring (or using) the array within the
1151 program before the string (lexically). (Someday it will simply assume
1152 that an unbackslashed @ interpolates an array.)
1154 =item Insecure dependency in %s
1156 (F) You tried to do something that the tainting mechanism didn't like.
1157 The tainting mechanism is turned on when you're running setuid or setgid,
1158 or when you specify B<-T> to turn it on explicitly. The tainting mechanism
1159 labels all data that's derived directly or indirectly from the user,
1160 who is considered to be unworthy of your trust. If any such data is
1161 used in a "dangerous" operation, you get this error. See L<perlsec>
1162 for more information.
1164 =item Insecure directory in %s
1166 (F) You can't use system(), exec(), or a piped open in a setuid or setgid
1167 script if C<$ENV{PATH}> contains a directory that is writable by the world.
1172 (F) You can't use system(), exec(), or a piped open in a setuid or
1173 setgid script if C<$ENV{PATH}> is derived from data supplied (or
1174 potentially supplied) by the user. The script must set the path to a
1175 known value, using trustworthy data. See L<perlsec>.
1177 =item Integer overflow in hex number
1179 (S) The literal hex number you have specified is too big for your
1180 architecture. On a 32-bit architecture the largest hex literal is
1183 =item Integer overflow in octal number
1185 (S) The literal octal number you have specified is too big for your
1186 architecture. On a 32-bit architecture the largest octal literal is
1189 =item Internal inconsistency in tracking vforks
1191 (S) A warning peculiar to VMS. Perl keeps track of the number
1192 of times you've called C<fork> and C<exec>, to determine
1193 whether the current call to C<exec> should affect the current
1194 script or a subprocess (see L<perlvms/exec>). Somehow, this count
1195 has become scrambled, so Perl is making a guess and treating
1196 this C<exec> as a request to terminate the Perl script
1197 and execute the specified command.
1199 =item internal disaster in regexp
1201 (P) Something went badly wrong in the regular expression parser.
1203 =item internal urp in regexp at /%s/
1205 (P) Something went badly awry in the regular expression parser.
1207 =item invalid [] range in regexp
1209 (F) The range specified in a character class had a minimum character
1210 greater than the maximum character. See L<perlre>.
1212 =item ioctl is not implemented
1214 (F) Your machine apparently doesn't implement ioctl(), which is pretty
1215 strange for a machine that supports C.
1217 =item junk on end of regexp
1219 (P) The regular expression parser is confused.
1221 =item Label not found for "last %s"
1223 (F) You named a loop to break out of, but you're not currently in a
1224 loop of that name, not even if you count where you were called from.
1225 See L<perlfunc/last>.
1227 =item Label not found for "next %s"
1229 (F) You named a loop to continue, but you're not currently in a loop of
1230 that name, not even if you count where you were called from. See
1233 =item Label not found for "redo %s"
1235 (F) You named a loop to restart, but you're not currently in a loop of
1236 that name, not even if you count where you were called from. See
1239 =item listen() on closed fd
1241 (W) You tried to do a listen on a closed socket. Did you forget to check
1242 the return value of your socket() call? See L<perlfunc/listen>.
1244 =item Method for operation %s not found in package %s during blessing
1246 (F) An attempt was made to specify an entry in an overloading table that
1247 doesn't resolve to a valid subroutine. See L<overload>.
1249 =item Might be a runaway multi-line %s string starting on line %d
1251 (S) An advisory indicating that the previous error may have been caused
1252 by a missing delimiter on a string or pattern, because it eventually
1253 ended earlier on the current line.
1255 =item Misplaced _ in number
1257 (W) An underline in a decimal constant wasn't on a 3-digit boundary.
1259 =item Missing $ on loop variable
1261 (F) Apparently you've been programming in B<csh> too much. Variables are always
1262 mentioned with the $ in Perl, unlike in the shells, where it can vary from
1263 one line to the next.
1265 =item Missing comma after first argument to %s function
1267 (F) While certain functions allow you to specify a filehandle or an
1268 "indirect object" before the argument list, this ain't one of them.
1270 =item Missing operator before %s?
1272 (S) This is an educated guess made in conjunction with the message "%s
1273 found where operator expected". Often the missing operator is a comma.
1275 =item Missing right bracket
1277 (F) The lexer counted more opening curly brackets (braces) than closing ones.
1278 As a general rule, you'll find it's missing near the place you were last
1281 =item Missing semicolon on previous line?
1283 (S) This is an educated guess made in conjunction with the message "%s
1284 found where operator expected". Don't automatically put a semicolon on
1285 the previous line just because you saw this message.
1287 =item Modification of a read-only value attempted
1289 (F) You tried, directly or indirectly, to change the value of a
1290 constant. You didn't, of course, try "2 = 1", because the compiler
1291 catches that. But an easy way to do the same thing is:
1293 sub mod { $_[0] = 1 }
1296 Another way is to assign to a substr() that's off the end of the string.
1298 =item Modification of non-creatable array value attempted, subscript %d
1300 (F) You tried to make an array value spring into existence, and the
1301 subscript was probably negative, even counting from end of the array
1304 =item Modification of non-creatable hash value attempted, subscript "%s"
1306 (F) You tried to make a hash value spring into existence, and it couldn't
1307 be created for some peculiar reason.
1309 =item Module name must be constant
1311 (F) Only a bare module name is allowed as the first argument to a "use".
1313 =item msg%s not implemented
1315 (F) You don't have System V message IPC on your system.
1317 =item Multidimensional syntax %s not supported
1319 (W) Multidimensional arrays aren't written like C<$foo[1,2,3]>. They're written
1320 like C<$foo[1][2][3]>, as in C.
1322 =item Name "%s::%s" used only once: possible typo
1324 (W) Typographical errors often show up as unique variable names.
1325 If you had a good reason for having a unique name, then just mention
1326 it again somehow to suppress the message. The C<use vars> pragma is
1327 provided for just this purpose.
1329 =item Negative length
1331 (F) You tried to do a read/write/send/recv operation with a buffer length
1332 that is less than 0. This is difficult to imagine.
1334 =item nested *?+ in regexp
1336 (F) You can't quantify a quantifier without intervening parentheses. So
1337 things like ** or +* or ?* are illegal.
1339 Note, however, that the minimal matching quantifiers, C<*?>, C<+?>, and C<??> appear
1340 to be nested quantifiers, but aren't. See L<perlre>.
1344 (F) The setuid emulator requires that scripts have a well-formed #! line
1345 even on machines that don't support the #! construct.
1347 =item No %s allowed while running setuid
1349 (F) Certain operations are deemed to be too insecure for a setuid or setgid
1350 script to even be allowed to attempt. Generally speaking there will be
1351 another way to do what you want that is, if not secure, at least securable.
1354 =item No B<-e> allowed in setuid scripts
1356 (F) A setuid script can't be specified by the user.
1358 =item No comma allowed after %s
1360 (F) A list operator that has a filehandle or "indirect object" is not
1361 allowed to have a comma between that and the following arguments.
1362 Otherwise it'd be just another one of the arguments.
1364 One possible cause for this is that you expected to have imported a
1365 constant to your name space with B<use> or B<import> while no such
1366 importing took place, it may for example be that your operating system
1367 does not support that particular constant. Hopefully you did use an
1368 explicit import list for the constants you expect to see, please see
1369 L<perlfunc/use> and L<perlfunc/import>. While an explicit import list
1370 would probably have caught this error earlier it naturally does not
1371 remedy the fact that your operating system still does not support that
1372 constant. Maybe you have a typo in the constants of the symbol import
1373 list of B<use> or B<import> or in the constant name at the line where
1374 this error was triggered?
1376 =item No command into which to pipe on command line
1378 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1379 and found a '|' at the end of the command line, so it doesn't know whither you
1380 want to pipe the output from this command.
1382 =item No DB::DB routine defined
1384 (F) The currently executing code was compiled with the B<-d> switch,
1385 but for some reason the perl5db.pl file (or some facsimile thereof)
1386 didn't define a routine to be called at the beginning of each
1387 statement. Which is odd, because the file should have been required
1388 automatically, and should have blown up the require if it didn't parse
1391 =item No dbm on this machine
1393 (P) This is counted as an internal error, because every machine should
1394 supply dbm nowadays, because Perl comes with SDBM. See L<SDBM_File>.
1396 =item No DBsub routine
1398 (F) The currently executing code was compiled with the B<-d> switch,
1399 but for some reason the perl5db.pl file (or some facsimile thereof)
1400 didn't define a DB::sub routine to be called at the beginning of each
1401 ordinary subroutine call.
1403 =item No error file after 2E<gt> or 2E<gt>E<gt> on command line
1405 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1406 and found a '2E<gt>' or a '2E<gt>E<gt>' on the command line, but can't find
1407 the name of the file to which to write data destined for stderr.
1409 =item No input file after E<lt> on command line
1411 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1412 and found a 'E<lt>' on the command line, but can't find the name of the file
1413 from which to read data for stdin.
1415 =item No output file after E<gt> on command line
1417 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1418 and found a lone 'E<gt>' at the end of the command line, so it doesn't know
1419 whither you wanted to redirect stdout.
1421 =item No output file after E<gt> or E<gt>E<gt> on command line
1423 (F) An error peculiar to VMS. Perl handles its own command line redirection,
1424 and found a 'E<gt>' or a 'E<gt>E<gt>' on the command line, but can't find the
1425 name of the file to which to write data destined for stdout.
1427 =item No Perl script found in input
1429 (F) You called C<perl -x>, but no line was found in the file beginning
1430 with #! and containing the word "perl".
1432 =item No setregid available
1434 (F) Configure didn't find anything resembling the setregid() call for
1437 =item No setreuid available
1439 (F) Configure didn't find anything resembling the setreuid() call for
1442 =item No space allowed after B<-I>
1444 (F) The argument to B<-I> must follow the B<-I> immediately with no
1447 =item No such pipe open
1449 (P) An error peculiar to VMS. The internal routine my_pclose() tried to
1450 close a pipe which hadn't been opened. This should have been caught earlier as
1451 an attempt to close an unopened filehandle.
1453 =item No such signal: SIG%s
1455 (W) You specified a signal name as a subscript to %SIG that was not recognized.
1456 Say C<kill -l> in your shell to see the valid signal names on your system.
1458 =item Not a CODE reference
1460 (F) Perl was trying to evaluate a reference to a code value (that is, a
1461 subroutine), but found a reference to something else instead. You can
1462 use the ref() function to find out what kind of ref it really was.
1463 See also L<perlref>.
1465 =item Not a format reference
1467 (F) I'm not sure how you managed to generate a reference to an anonymous
1468 format, but this indicates you did, and that it didn't exist.
1470 =item Not a GLOB reference
1472 (F) Perl was trying to evaluate a reference to a "typeglob" (that is,
1473 a symbol table entry that looks like C<*foo>), but found a reference to
1474 something else instead. You can use the ref() function to find out
1475 what kind of ref it really was. See L<perlref>.
1477 =item Not a HASH reference
1479 (F) Perl was trying to evaluate a reference to a hash value, but
1480 found a reference to something else instead. You can use the ref()
1481 function to find out what kind of ref it really was. See L<perlref>.
1483 =item Not a perl script
1485 (F) The setuid emulator requires that scripts have a well-formed #! line
1486 even on machines that don't support the #! construct. The line must
1489 =item Not a SCALAR reference
1491 (F) Perl was trying to evaluate a reference to a scalar value, but
1492 found a reference to something else instead. You can use the ref()
1493 function to find out what kind of ref it really was. See L<perlref>.
1495 =item Not a subroutine reference
1497 (F) Perl was trying to evaluate a reference to a code value (that is, a
1498 subroutine), but found a reference to something else instead. You can
1499 use the ref() function to find out what kind of ref it really was.
1500 See also L<perlref>.
1502 =item Not a subroutine reference in overload table
1504 (F) An attempt was made to specify an entry in an overloading table that
1505 doesn't somehow point to a valid subroutine. See L<overload>.
1507 =item Not an ARRAY reference
1509 (F) Perl was trying to evaluate a reference to an array value, but
1510 found a reference to something else instead. You can use the ref()
1511 function to find out what kind of ref it really was. See L<perlref>.
1513 =item Not enough arguments for %s
1515 (F) The function requires more arguments than you specified.
1517 =item Not enough format arguments
1519 (W) A format specified more picture fields than the next line supplied.
1522 =item Null filename used
1524 (F) You can't require the null filename, especially because on many machines
1525 that means the current directory! See L<perlfunc/require>.
1527 =item Null picture in formline
1529 (F) The first argument to formline must be a valid format picture
1530 specification. It was found to be empty, which probably means you
1531 supplied it an uninitialized value. See L<perlform>.
1533 =item NULL OP IN RUN
1535 (P) Some internal routine called run() with a null opcode pointer.
1539 (P) An attempt was made to realloc NULL.
1541 =item NULL regexp argument
1543 (P) The internal pattern matching routines blew it big time.
1545 =item NULL regexp parameter
1547 (P) The internal pattern matching routines are out of their gourd.
1549 =item Odd number of elements in hash list
1551 (S) You specified an odd number of elements to a hash list, which is odd,
1552 because hash lists come in key/value pairs.
1554 =item Offset outside string
1556 (F) You tried to do a read/write/send/recv operation with an offset
1557 pointing outside the buffer. This is difficult to imagine.
1558 The sole exception to this is that C<sysread()>ing past the buffer
1559 will extend the buffer and zero pad the new area.
1563 (S) An internal warning that the grammar is screwed up.
1567 (S) An internal warning that the grammar is screwed up.
1569 =item Operation `%s': no method found,%s
1571 (F) An attempt was made to perform an overloaded operation for which
1572 no handler was defined. While some handlers can be autogenerated in
1573 terms of other handlers, there is no default handler for any
1574 operation, unless C<fallback> overloading key is specified to be
1575 true. See L<overload>.
1577 =item Operator or semicolon missing before %s
1579 (S) You used a variable or subroutine call where the parser was
1580 expecting an operator. The parser has assumed you really meant
1581 to use an operator, but this is highly likely to be incorrect.
1582 For example, if you say "*foo *foo" it will be interpreted as
1583 if you said "*foo * 'foo'".
1585 =item Out of memory for yacc stack
1587 (F) The yacc parser wanted to grow its stack so it could continue parsing,
1588 but realloc() wouldn't give it more memory, virtual or otherwise.
1590 =item Out of memory!
1592 (X|F) The malloc() function returned 0, indicating there was insufficient
1593 remaining memory (or virtual memory) to satisfy the request.
1595 The request was judged to be small, so the possibility to trap it
1596 depends on the way perl was compiled. By default it is not trappable.
1597 However, if compiled for this, Perl may use the contents of C<$^M> as
1598 an emergency pool after die()ing with this message. In this case the
1599 error is trappable I<once>.
1601 =item Out of memory during request for %s
1603 (F) The malloc() function returned 0, indicating there was insufficient
1604 remaining memory (or virtual memory) to satisfy the request. However,
1605 the request was judged large enough (compile-time default is 64K), so
1606 a possibility to shut down by trapping this error is granted.
1610 (W) A single call to write() produced more lines than can fit on a page.
1613 =item panic: ck_grep
1615 (P) Failed an internal consistency check trying to compile a grep.
1617 =item panic: ck_split
1619 (P) Failed an internal consistency check trying to compile a split.
1621 =item panic: corrupt saved stack index
1623 (P) The savestack was requested to restore more localized values than there
1624 are in the savestack.
1628 (P) We popped the context stack to an eval context, and then discovered
1629 it wasn't an eval context.
1631 =item panic: do_match
1633 (P) The internal pp_match() routine was called with invalid operational data.
1635 =item panic: do_split
1637 (P) Something terrible went wrong in setting up for the split.
1639 =item panic: do_subst
1641 (P) The internal pp_subst() routine was called with invalid operational data.
1643 =item panic: do_trans
1645 (P) The internal do_trans() routine was called with invalid operational data.
1649 (P) We popped the context stack to a context with the specified label,
1650 and then discovered it wasn't a context we know how to do a goto in.
1652 =item panic: INTERPCASEMOD
1654 (P) The lexer got into a bad state at a case modifier.
1656 =item panic: INTERPCONCAT
1658 (P) The lexer got into a bad state parsing a string with brackets.
1662 (P) We popped the context stack to a block context, and then discovered
1663 it wasn't a block context.
1665 =item panic: leave_scope clearsv
1667 (P) A writable lexical variable became read-only somehow within the scope.
1669 =item panic: leave_scope inconsistency
1671 (P) The savestack probably got out of sync. At least, there was an
1672 invalid enum on the top of it.
1676 (P) Something requested a negative number of bytes of malloc.
1678 =item panic: mapstart
1680 (P) The compiler is screwed up with respect to the map() function.
1682 =item panic: null array
1684 (P) One of the internal array routines was passed a null AV pointer.
1686 =item panic: pad_alloc
1688 (P) The compiler got confused about which scratch pad it was allocating
1689 and freeing temporaries and lexicals from.
1691 =item panic: pad_free curpad
1693 (P) The compiler got confused about which scratch pad it was allocating
1694 and freeing temporaries and lexicals from.
1696 =item panic: pad_free po
1698 (P) An invalid scratch pad offset was detected internally.
1700 =item panic: pad_reset curpad
1702 (P) The compiler got confused about which scratch pad it was allocating
1703 and freeing temporaries and lexicals from.
1705 =item panic: pad_sv po
1707 (P) An invalid scratch pad offset was detected internally.
1709 =item panic: pad_swipe curpad
1711 (P) The compiler got confused about which scratch pad it was allocating
1712 and freeing temporaries and lexicals from.
1714 =item panic: pad_swipe po
1716 (P) An invalid scratch pad offset was detected internally.
1718 =item panic: pp_iter
1720 (P) The foreach iterator got called in a non-loop context frame.
1722 =item panic: realloc
1724 (P) Something requested a negative number of bytes of realloc.
1726 =item panic: restartop
1728 (P) Some internal routine requested a goto (or something like it), and
1729 didn't supply the destination.
1733 (P) We popped the context stack to a subroutine or eval context, and
1734 then discovered it wasn't a subroutine or eval context.
1736 =item panic: scan_num
1738 (P) scan_num() got called on something that wasn't a number.
1740 =item panic: sv_insert
1742 (P) The sv_insert() routine was told to remove more string than there
1745 =item panic: top_env
1747 (P) The compiler attempted to do a goto, or something weird like that.
1751 (P) The lexer got into a bad state while processing a case modifier.
1753 =item Pareneses missing around "%s" list
1755 (W) You said something like
1761 my ($foo, $bar) = @_;
1763 Remember that "my" and "local" bind closer than comma.
1765 =item Perl %3.3f required--this is only version %s, stopped
1767 (F) The module in question uses features of a version of Perl more recent
1768 than the currently running version. How long has it been since you upgraded,
1769 anyway? See L<perlfunc/require>.
1771 =item Permission denied
1773 (F) The setuid emulator in suidperl decided you were up to no good.
1775 =item pid %d not a child
1777 (W) A warning peculiar to VMS. Waitpid() was asked to wait for a process which
1778 isn't a subprocess of the current process. While this is fine from VMS'
1779 perspective, it's probably not what you intended.
1781 =item POSIX getpgrp can't take an argument
1783 (F) Your C compiler uses POSIX getpgrp(), which takes no argument, unlike
1784 the BSD version, which takes a pid.
1786 =item Possible attempt to put comments in qw() list
1788 (W) qw() lists contain items separated by whitespace; as with literal
1789 strings, comment characters are not ignored, but are instead treated
1790 as literal data. (You may have used different delimiters than the
1791 exclamation marks parentheses shown here; braces are also frequently
1794 You probably wrote something like this:
1801 when you should have written this:
1808 If you really want comments, build your list the
1809 old-fashioned way, with quotes and commas:
1813 'b', # another comment
1816 =item Possible attempt to separate words with commas
1818 (W) qw() lists contain items separated by whitespace; therefore commas
1819 aren't needed to separate the items. (You may have used different
1820 delimiters than the parentheses shown here; braces are also frequently
1823 You probably wrote something like this:
1827 which puts literal commas into some of the list items. Write it without
1828 commas if you don't want them to appear in your data:
1832 =item Possible memory corruption: %s overflowed 3rd argument
1834 (F) An ioctl() or fcntl() returned more than Perl was bargaining for.
1835 Perl guesses a reasonable buffer size, but puts a sentinel byte at the
1836 end of the buffer just in case. This sentinel byte got clobbered, and
1837 Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
1839 =item Precedence problem: open %s should be open(%s)
1841 (S) The old irregular construct
1845 is now misinterpreted as
1849 because of the strict regularization of Perl 5's grammar into unary
1850 and list operators. (The old open was a little of both.) You must
1851 put parentheses around the filehandle, or use the new "or" operator
1854 =item print on closed filehandle %s
1856 (W) The filehandle you're printing on got itself closed sometime before now.
1857 Check your logic flow.
1859 =item printf on closed filehandle %s
1861 (W) The filehandle you're writing to got itself closed sometime before now.
1862 Check your logic flow.
1864 =item Probable precedence problem on %s
1866 (W) The compiler found a bare word where it expected a conditional,
1867 which often indicates that an || or && was parsed as part of the
1868 last argument of the previous construct, for example:
1872 =item Prototype mismatch: (%s) vs (%s)
1874 (S) The subroutine being defined had a pre-declared (forward) declaration
1875 with a different function prototype.
1877 =item Read on closed filehandle E<lt>%sE<gt>
1879 (W) The filehandle you're reading from got itself closed sometime before now.
1880 Check your logic flow.
1882 =item Reallocation too large: %lx
1884 (F) You can't allocate more than 64K on an MSDOS machine.
1886 =item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
1888 (F) You can't use the B<-D> option unless the code to produce the
1889 desired output is compiled into Perl, which entails some overhead,
1890 which is why it's currently left out of your copy.
1892 =item Recursive inheritance detected
1894 (F) More than 100 levels of inheritance were used. Probably indicates
1895 an unintended loop in your inheritance hierarchy.
1897 =item Reference miscount in sv_replace()
1899 (W) The internal sv_replace() function was handed a new SV with a
1900 reference count of other than 1.
1902 =item regexp memory corruption
1904 (P) The regular expression engine got confused by what the regular
1905 expression compiler gave it.
1907 =item regexp out of space
1909 (P) A "can't happen" error, because safemalloc() should have caught it earlier.
1911 =item regexp too big
1913 (F) The current implementation of regular expressions uses shorts as
1914 address offsets within a string. Unfortunately this means that if
1915 the regular expression compiles to longer than 32767, it'll blow up.
1916 Usually when you want a regular expression this big, there is a better
1917 way to do it with multiple statements. See L<perlre>.
1919 =item Reversed %s= operator
1921 (W) You wrote your assignment operator backwards. The = must always
1922 comes last, to avoid ambiguity with subsequent unary operators.
1924 =item Runaway format
1926 (F) Your format contained the ~~ repeat-until-blank sequence, but it
1927 produced 200 lines at once, and the 200th line looked exactly like the
1928 199th line. Apparently you didn't arrange for the arguments to exhaust
1929 themselves, either by using ^ instead of @ (for scalar variables), or by
1930 shifting or popping (for array variables). See L<perlform>.
1932 =item Scalar value @%s[%s] better written as $%s[%s]
1934 (W) You've used an array slice (indicated by @) to select a single element of
1935 an array. Generally it's better to ask for a scalar value (indicated by $).
1936 The difference is that C<$foo[&bar]> always behaves like a scalar, both when
1937 assigning to it and when evaluating its argument, while C<@foo[&bar]> behaves
1938 like a list when you assign to it, and provides a list context to its
1939 subscript, which can do weird things if you're expecting only one subscript.
1941 On the other hand, if you were actually hoping to treat the array
1942 element as a list, you need to look into how references work, because
1943 Perl will not magically convert between scalars and lists for you. See
1946 =item Scalar value @%s{%s} better written as $%s{%s}
1948 (W) You've used a hash slice (indicated by @) to select a single element of
1949 a hash. Generally it's better to ask for a scalar value (indicated by $).
1950 The difference is that C<$foo{&bar}> always behaves like a scalar, both when
1951 assigning to it and when evaluating its argument, while C<@foo{&bar}> behaves
1952 like a list when you assign to it, and provides a list context to its
1953 subscript, which can do weird things if you're expecting only one subscript.
1955 On the other hand, if you were actually hoping to treat the hash
1956 element as a list, you need to look into how references work, because
1957 Perl will not magically convert between scalars and lists for you. See
1960 =item Script is not setuid/setgid in suidperl
1962 (F) Oddly, the suidperl program was invoked on a script with its setuid
1963 or setgid bit not set. This doesn't make much sense.
1965 =item Search pattern not terminated
1967 (F) The lexer couldn't find the final delimiter of a // or m{}
1968 construct. Remember that bracketing delimiters count nesting level.
1970 =item seek() on unopened file
1972 (W) You tried to use the seek() function on a filehandle that was either
1973 never opened or has been closed since.
1975 =item select not implemented
1977 (F) This machine doesn't implement the select() system call.
1979 =item sem%s not implemented
1981 (F) You don't have System V semaphore IPC on your system.
1983 =item semi-panic: attempt to dup freed string
1985 (S) The internal newSVsv() routine was called to duplicate a scalar
1986 that had previously been marked as free.
1988 =item Semicolon seems to be missing
1990 (W) A nearby syntax error was probably caused by a missing semicolon,
1991 or possibly some other missing operator, such as a comma.
1993 =item Send on closed socket
1995 (W) The filehandle you're sending to got itself closed sometime before now.
1996 Check your logic flow.
1998 =item Sequence (?#... not terminated
2000 (F) A regular expression comment must be terminated by a closing
2001 parenthesis. Embedded parentheses aren't allowed. See L<perlre>.
2003 =item Sequence (?%s...) not implemented
2005 (F) A proposed regular expression extension has the character reserved
2006 but has not yet been written. See L<perlre>.
2008 =item Sequence (?%s...) not recognized
2010 (F) You used a regular expression extension that doesn't make sense.
2015 Also known as "500 Server error".
2017 B<This is a CGI error, not a Perl error>.
2019 You need to make sure your script is executable, is accessible by the user
2020 CGI is running the script under (which is probably not the user account you
2021 tested it under), does not rely on any environment variables (like PATH)
2022 from the user it isn't running under, and isn't in a location where the CGI
2023 server can't find it, basically, more or less. Please see the following
2024 for more information:
2026 http://www.perl.com/perl/faq/idiots-guide.html
2027 http://www.perl.com/perl/faq/perl-cgi-faq.html
2028 ftp://rtfm.mit.edu/pub/usenet/news.answers/www/cgi-faq
2029 http://hoohoo.ncsa.uiuc.edu/cgi/interface.html
2030 http://www-genome.wi.mit.edu/WWW/faqs/www-security-faq.html
2032 =item setegid() not implemented
2034 (F) You tried to assign to C<$)>, and your operating system doesn't support
2035 the setegid() system call (or equivalent), or at least Configure didn't
2038 =item seteuid() not implemented
2040 (F) You tried to assign to C<$E<gt>>, and your operating system doesn't support
2041 the seteuid() system call (or equivalent), or at least Configure didn't
2044 =item setrgid() not implemented
2046 (F) You tried to assign to C<$(>, and your operating system doesn't support
2047 the setrgid() system call (or equivalent), or at least Configure didn't
2050 =item setruid() not implemented
2052 (F) You tried to assign to C<$<lt>>, and your operating system doesn't support
2053 the setruid() system call (or equivalent), or at least Configure didn't
2056 =item Setuid/gid script is writable by world
2058 (F) The setuid emulator won't run a script that is writable by the world,
2059 because the world might have written on it already.
2061 =item shm%s not implemented
2063 (F) You don't have System V shared memory IPC on your system.
2065 =item shutdown() on closed fd
2067 (W) You tried to do a shutdown on a closed socket. Seems a bit superfluous.
2069 =item SIG%s handler "%s" not defined
2071 (W) The signal handler named in %SIG doesn't, in fact, exist. Perhaps you
2072 put it into the wrong package?
2074 =item sort is now a reserved word
2076 (F) An ancient error message that almost nobody ever runs into anymore.
2077 But before sort was a keyword, people sometimes used it as a filehandle.
2079 =item Sort subroutine didn't return a numeric value
2081 (F) A sort comparison routine must return a number. You probably blew
2082 it by not using C<E<lt>=E<gt>> or C<cmp>, or by not using them correctly.
2083 See L<perlfunc/sort>.
2085 =item Sort subroutine didn't return single value
2087 (F) A sort comparison subroutine may not return a list value with more
2088 or less than one element. See L<perlfunc/sort>.
2092 (P) The split was looping infinitely. (Obviously, a split shouldn't iterate
2093 more times than there are characters of input, which is what happened.)
2094 See L<perlfunc/split>.
2096 =item Stat on unopened file E<lt>%sE<gt>
2098 (W) You tried to use the stat() function (or an equivalent file test)
2099 on a filehandle that was either never opened or has been closed since.
2101 =item Statement unlikely to be reached
2103 (W) You did an exec() with some statement after it other than a die().
2104 This is almost always an error, because exec() never returns unless
2105 there was a failure. You probably wanted to use system() instead,
2106 which does return. To suppress this warning, put the exec() in a block
2109 =item Stub found while resolving method `%s' overloading `%s' in package `%s'
2111 (P) Overloading resolution over @ISA tree may be broken by importation stubs.
2112 Stubs should never be implicitely created, but explicit calls to C<can>
2115 =item Subroutine %s redefined
2117 (W) You redefined a subroutine. To suppress this warning, say
2121 eval "sub name { ... }";
2124 =item Substitution loop
2126 (P) The substitution was looping infinitely. (Obviously, a
2127 substitution shouldn't iterate more times than there are characters of
2128 input, which is what happened.) See the discussion of substitution in
2129 L<perlop/"Quote and Quote-like Operators">.
2131 =item Substitution pattern not terminated
2133 (F) The lexer couldn't find the interior delimiter of a s/// or s{}{}
2134 construct. Remember that bracketing delimiters count nesting level.
2136 =item Substitution replacement not terminated
2138 (F) The lexer couldn't find the final delimiter of a s/// or s{}{}
2139 construct. Remember that bracketing delimiters count nesting level.
2141 =item substr outside of string
2143 (W) You tried to reference a substr() that pointed outside of a string.
2144 That is, the absolute value of the offset was larger than the length of
2145 the string. See L<perlfunc/substr>.
2147 =item suidperl is no longer needed since %s
2149 (F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but a
2150 version of the setuid emulator somehow got run anyway.
2154 (F) Probably means you had a syntax error. Common reasons include:
2156 A keyword is misspelled.
2157 A semicolon is missing.
2159 An opening or closing parenthesis is missing.
2160 An opening or closing brace is missing.
2161 A closing quote is missing.
2163 Often there will be another error message associated with the syntax
2164 error giving more information. (Sometimes it helps to turn on B<-w>.)
2165 The error message itself often tells you where it was in the line when
2166 it decided to give up. Sometimes the actual error is several tokens
2167 before this, because Perl is good at understanding random input.
2168 Occasionally the line number may be misleading, and once in a blue moon
2169 the only way to figure out what's triggering the error is to call
2170 C<perl -c> repeatedly, chopping away half the program each time to see
2171 if the error went away. Sort of the cybernetic version of S<20 questions>.
2173 =item syntax error at line %d: `%s' unexpected
2175 (A) You've accidentally run your script through the Bourne shell
2176 instead of Perl. Check the #! line, or manually feed your script
2179 =item System V IPC is not implemented on this machine
2181 (F) You tried to do something with a function beginning with "sem", "shm",
2182 or "msg". See L<perlfunc/semctl>, for example.
2184 =item Syswrite on closed filehandle
2186 (W) The filehandle you're writing to got itself closed sometime before now.
2187 Check your logic flow.
2189 =item tell() on unopened file
2191 (W) You tried to use the tell() function on a filehandle that was either
2192 never opened or has been closed since.
2194 =item Test on unopened file E<lt>%sE<gt>
2196 (W) You tried to invoke a file test operator on a filehandle that isn't
2197 open. Check your logic. See also L<perlfunc/-X>.
2199 =item That use of $[ is unsupported
2201 (F) Assignment to C<$[> is now strictly circumscribed, and interpreted as
2202 a compiler directive. You may say only one of
2211 This is to prevent the problem of one module changing the array base
2212 out from under another module inadvertently. See L<perlvar/$[>.
2214 =item The %s function is unimplemented
2216 The function indicated isn't implemented on this architecture, according
2217 to the probings of Configure.
2219 =item The crypt() function is unimplemented due to excessive paranoia
2221 (F) Configure couldn't find the crypt() function on your machine,
2222 probably because your vendor didn't supply it, probably because they
2223 think the U.S. Government thinks it's a secret, or at least that they
2224 will continue to pretend that it is. And if you quote me on that, I
2227 =item The stat preceding C<-l _> wasn't an lstat
2229 (F) It makes no sense to test the current stat buffer for symbolic linkhood
2230 if the last stat that wrote to the stat buffer already went past
2231 the symlink to get to the real file. Use an actual filename instead.
2233 =item times not implemented
2235 (F) Your version of the C library apparently doesn't do times(). I suspect
2236 you're not running on Unix.
2238 =item Too few args to syscall
2240 (F) There has to be at least one argument to syscall() to specify the
2241 system call to call, silly dilly.
2243 =item Too late for "B<-T>" option
2245 (X) The #! line (or local equivalent) in a Perl script contains the
2246 B<-T> option, but Perl was not invoked with B<-T> in its argument
2247 list. This is an error because, by the time Perl discovers a B<-T> in
2248 a script, it's too late to properly taint everything from the
2249 environment. So Perl gives up.
2251 If the Perl script is being executed as a command using the #!
2252 mechanism (or its local equivalent), this error can usually be fixed
2253 by editing the #! line so that the B<-T> option is a part of Perl's
2254 first argument: e.g. change C<perl -n -T> to C<perl -T -n>.
2256 If the Perl script is being executed as C<perl scriptname>, then the
2257 B<-T> option must appear on the command line: C<perl -T scriptname>.
2263 (A) You've accidentally run your script through B<csh> instead
2264 of Perl. Check the #! line, or manually feed your script into
2267 =item Too many args to syscall
2269 (F) Perl supports a maximum of only 14 args to syscall().
2271 =item Too many arguments for %s
2273 (F) The function requires fewer arguments than you specified.
2275 =item trailing \ in regexp
2277 (F) The regular expression ends with an unbackslashed backslash. Backslash
2280 =item Translation pattern not terminated
2282 (F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
2285 =item Translation replacement not terminated
2287 (F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
2290 =item truncate not implemented
2292 (F) Your machine doesn't implement a file truncation mechanism that
2293 Configure knows about.
2295 =item Type of arg %d to %s must be %s (not %s)
2297 (F) This function requires the argument in that position to be of a
2298 certain type. Arrays must be @NAME or C<@{EXPR}>. Hashes must be
2299 %NAME or C<%{EXPR}>. No implicit dereferencing is allowed--use the
2300 {EXPR} forms as an explicit dereference. See L<perlref>.
2302 =item umask: argument is missing initial 0
2304 (W) A umask of 222 is incorrect. It should be 0222, because octal literals
2305 always start with 0 in Perl, as in C.
2307 =item Unable to create sub named "%s"
2309 (F) You attempted to create or access a subroutine with an illegal name.
2311 =item Unbalanced context: %d more PUSHes than POPs
2313 (W) The exit code detected an internal inconsistency in how many execution
2314 contexts were entered and left.
2316 =item Unbalanced saves: %d more saves than restores
2318 (W) The exit code detected an internal inconsistency in how many
2319 values were temporarily localized.
2321 =item Unbalanced scopes: %d more ENTERs than LEAVEs
2323 (W) The exit code detected an internal inconsistency in how many blocks
2324 were entered and left.
2326 =item Unbalanced tmps: %d more allocs than frees
2328 (W) The exit code detected an internal inconsistency in how many mortal
2329 scalars were allocated and freed.
2331 =item Undefined format "%s" called
2333 (F) The format indicated doesn't seem to exist. Perhaps it's really in
2334 another package? See L<perlform>.
2336 =item Undefined sort subroutine "%s" called
2338 (F) The sort comparison routine specified doesn't seem to exist. Perhaps
2339 it's in a different package? See L<perlfunc/sort>.
2341 =item Undefined subroutine &%s called
2343 (F) The subroutine indicated hasn't been defined, or if it was, it
2344 has since been undefined.
2346 =item Undefined subroutine called
2348 (F) The anonymous subroutine you're trying to call hasn't been defined,
2349 or if it was, it has since been undefined.
2351 =item Undefined subroutine in sort
2353 (F) The sort comparison routine specified is declared but doesn't seem to
2354 have been defined yet. See L<perlfunc/sort>.
2356 =item Undefined top format "%s" called
2358 (F) The format indicated doesn't seem to exist. Perhaps it's really in
2359 another package? See L<perlform>.
2361 =item unexec of %s into %s failed!
2363 (F) The unexec() routine failed for some reason. See your local FSF
2364 representative, who probably put it there in the first place.
2366 =item Unknown BYTEORDER
2368 (F) There are no byte-swapping functions for a machine with this byte order.
2370 =item unmatched () in regexp
2372 (F) Unbackslashed parentheses must always be balanced in regular
2373 expressions. If you're a vi user, the % key is valuable for finding
2374 the matching parenthesis. See L<perlre>.
2376 =item Unmatched right bracket
2378 (F) The lexer counted more closing curly brackets (braces) than opening
2379 ones, so you're probably missing an opening bracket. As a general
2380 rule, you'll find the missing one (so to speak) near the place you were
2383 =item unmatched [] in regexp
2385 (F) The brackets around a character class must match. If you wish to
2386 include a closing bracket in a character class, backslash it or put it first.
2389 =item Unquoted string "%s" may clash with future reserved word
2391 (W) You used a bare word that might someday be claimed as a reserved word.
2392 It's best to put such a word in quotes, or capitalize it somehow, or insert
2393 an underbar into it. You might also declare it as a subroutine.
2395 =item Unrecognized character \%03o ignored
2397 (S) A garbage character was found in the input, and ignored, in case it's
2398 a weird control character on an EBCDIC machine, or some such.
2400 =item Unrecognized signal name "%s"
2402 (F) You specified a signal name to the kill() function that was not recognized.
2403 Say C<kill -l> in your shell to see the valid signal names on your system.
2405 =item Unrecognized switch: -%s
2407 (F) You specified an illegal option to Perl. Don't do that.
2408 (If you think you didn't do that, check the #! line to see if it's
2409 supplying the bad switch on your behalf.)
2411 =item Unsuccessful %s on filename containing newline
2413 (W) A file operation was attempted on a filename, and that operation
2414 failed, PROBABLY because the filename contained a newline, PROBABLY
2415 because you forgot to chop() or chomp() it off. See L<perlfunc/chop>.
2417 =item Unsupported directory function "%s" called
2419 (F) Your machine doesn't support opendir() and readdir().
2421 =item Unsupported function %s
2423 (F) This machines doesn't implement the indicated function, apparently.
2424 At least, Configure doesn't think so.
2426 =item Unsupported socket function "%s" called
2428 (F) Your machine doesn't support the Berkeley socket mechanism, or at
2429 least that's what Configure thought.
2431 =item Unterminated E<lt>E<gt> operator
2433 (F) The lexer saw a left angle bracket in a place where it was expecting
2434 a term, so it's looking for the corresponding right angle bracket, and not
2435 finding it. Chances are you left some needed parentheses out earlier in
2436 the line, and you really meant a "less than".
2438 =item Use of $# is deprecated
2440 (D) This was an ill-advised attempt to emulate a poorly defined B<awk> feature.
2441 Use an explicit printf() or sprintf() instead.
2443 =item Use of $* is deprecated
2445 (D) This variable magically turned on multi-line pattern matching, both for
2446 you and for any luckless subroutine that you happen to call. You should
2447 use the new C<//m> and C<//s> modifiers now to do that without the dangerous
2448 action-at-a-distance effects of C<$*>.
2450 =item Use of %s in printf format not supported
2452 (F) You attempted to use a feature of printf that is accessible from
2453 only C. This usually means there's a better way to do it in Perl.
2455 =item Use of %s is deprecated
2457 (D) The construct indicated is no longer recommended for use, generally
2458 because there's a better way to do it, and also because the old way has
2461 =item Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated
2463 (D) You are now encouraged to use the explicitly quoted form if you
2464 wish to use a blank line as the terminator of the here-document.
2466 =item Use of implicit split to @_ is deprecated
2468 (D) It makes a lot of work for the compiler when you clobber a
2469 subroutine's argument list, so it's better if you assign the results of
2470 a split() explicitly to an array (or list).
2472 =item Use of uninitialized value
2474 (W) An undefined value was used as if it were already defined. It was
2475 interpreted as a "" or a 0, but maybe it was a mistake. To suppress this
2476 warning assign an initial value to your variables.
2478 =item Useless use of %s in void context
2480 (W) You did something without a side effect in a context that does nothing
2481 with the return value, such as a statement that doesn't return a value
2482 from a block, or the left side of a scalar comma operator. Very often
2483 this points not to stupidity on your part, but a failure of Perl to parse
2484 your program the way you thought it would. For example, you'd get this
2485 if you mixed up your C precedence with Python precedence and said
2489 when you meant to say
2491 ($one, $two) = (1, 2);
2493 Another common error is to use ordinary parentheses to construct a list
2494 reference when you should be using square or curly brackets, for
2499 when you should have said
2503 The square brackets explicitly turn a list value into a scalar value,
2504 while parentheses do not. So when a parenthesized list is evaluated in
2505 a scalar context, the comma is treated like C's comma operator, which
2506 throws away the left argument, which is not what you want. See
2507 L<perlref> for more on this.
2509 =item untie attempted while %d inner references still exist
2511 (W) A copy of the object returned from C<tie> (or C<tied>) was still
2512 valid when C<untie> was called.
2514 =item Value of %s can be "0"; test with defined()
2516 (W) In a conditional expression, you used <HANDLE>, <*> (glob), C<each()>,
2517 or C<readdir()> as a boolean value. Each of these constructs can return a
2518 value of "0"; that would make the conditional expression false, which is
2519 probably not what you intended. When using these constructs in conditional
2520 expressions, test their values with the C<defined> operator.
2522 =item Variable "%s" is not imported%s
2524 (F) While "use strict" in effect, you referred to a global variable
2525 that you apparently thought was imported from another module, because
2526 something else of the same name (usually a subroutine) is exported
2527 by that module. It usually means you put the wrong funny character
2528 on the front of your variable.
2530 =item Variable "%s" may be unavailable
2532 (W) An inner (nested) I<anonymous> subroutine is inside a I<named>
2533 subroutine, and outside that is another subroutine; and the anonymous
2534 (innermost) subroutine is referencing a lexical variable defined in
2535 the outermost subroutine. For example:
2537 sub outermost { my $a; sub middle { sub { $a } } }
2539 If the anonymous subroutine is called or referenced (directly or
2540 indirectly) from the outermost subroutine, it will share the variable
2541 as you would expect. But if the anonymous subroutine is called or
2542 referenced when the outermost subroutine is not active, it will see
2543 the value of the shared variable as it was before and during the
2544 *first* call to the outermost subroutine, which is probably not what
2547 In these circumstances, it is usually best to make the middle
2548 subroutine anonymous, using the C<sub {}> syntax. Perl has specific
2549 support for shared variables in nested anonymous subroutines; a named
2550 subroutine in between interferes with this feature.
2552 =item Variable "%s" will not stay shared
2554 (W) An inner (nested) I<named> subroutine is referencing a lexical
2555 variable defined in an outer subroutine.
2557 When the inner subroutine is called, it will probably see the value of
2558 the outer subroutine's variable as it was before and during the
2559 *first* call to the outer subroutine; in this case, after the first
2560 call to the outer subroutine is complete, the inner and outer
2561 subroutines will no longer share a common value for the variable. In
2562 other words, the variable will no longer be shared.
2564 Furthermore, if the outer subroutine is anonymous and references a
2565 lexical variable outside itself, then the outer and inner subroutines
2566 will I<never> share the given variable.
2568 This problem can usually be solved by making the inner subroutine
2569 anonymous, using the C<sub {}> syntax. When inner anonymous subs that
2570 reference variables in outer subroutines are called or referenced,
2571 they are automatically re-bound to the current values of such
2574 =item Variable syntax
2576 (A) You've accidentally run your script through B<csh> instead
2577 of Perl. Check the #! line, or manually feed your script into
2580 =item Warning: something's wrong
2582 (W) You passed warn() an empty string (the equivalent of C<warn "">) or
2583 you called it with no args and C<$_> was empty.
2585 =item Warning: unable to close filehandle %s properly
2587 (S) The implicit close() done by an open() got an error indication on the
2588 close(). This usually indicates your file system ran out of disk space.
2590 =item Warning: Use of "%s" without parentheses is ambiguous
2592 (S) You wrote a unary operator followed by something that looks like a
2593 binary operator that could also have been interpreted as a term or
2594 unary operator. For instance, if you know that the rand function
2595 has a default argument of 1.0, and you write
2599 you may THINK you wrote the same thing as
2603 but in actual fact, you got
2607 So put in parentheses to say what you really mean.
2609 =item Write on closed filehandle
2611 (W) The filehandle you're writing to got itself closed sometime before now.
2612 Check your logic flow.
2614 =item X outside of string
2616 (F) You had a pack template that specified a relative position before
2617 the beginning of the string being unpacked. See L<perlfunc/pack>.
2619 =item x outside of string
2621 (F) You had a pack template that specified a relative position after
2622 the end of the string being unpacked. See L<perlfunc/pack>.
2624 =item Xsub "%s" called in sort
2626 (F) The use of an external subroutine as a sort comparison is not yet supported.
2628 =item Xsub called in sort
2630 (F) The use of an external subroutine as a sort comparison is not yet supported.
2632 =item You can't use C<-l> on a filehandle
2634 (F) A filehandle represents an opened file, and when you opened the file it
2635 already went past any symlink you are presumably trying to look for.
2636 Use a filename instead.
2638 =item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
2640 (F) And you probably never will, because you probably don't have the
2641 sources to your kernel, and your vendor probably doesn't give a rip
2642 about what you want. Your best bet is to use the wrapsuid script in
2643 the eg directory to put a setuid C wrapper around your script.
2645 =item You need to quote "%s"
2647 (W) You assigned a bareword as a signal handler name. Unfortunately, you
2648 already have a subroutine of that name declared, which means that Perl 5
2649 will try to call the subroutine when the assignment is executed, which is
2650 probably not what you want. (If it IS what you want, put an & in front.)
2652 =item [gs]etsockopt() on closed fd
2654 (W) You tried to get or set a socket option on a closed socket.
2655 Did you forget to check the return value of your socket() call?
2656 See L<perlfunc/getsockopt>.
2658 =item \1 better written as $1
2660 (W) Outside of patterns, backreferences live on as variables. The use
2661 of backslashes is grandfathered on the right-hand side of a
2662 substitution, but stylistically it's better to use the variable form
2663 because other Perl programmers will expect it, and it works better
2664 if there are more than 9 backreferences.
2666 =item '|' and 'E<lt>' may not both be specified on command line
2668 (F) An error peculiar to VMS. Perl does its own command line redirection, and
2669 found that STDIN was a pipe, and that you also tried to redirect STDIN using
2670 'E<lt>'. Only one STDIN stream to a customer, please.
2672 =item '|' and 'E<gt>' may not both be specified on command line
2674 (F) An error peculiar to VMS. Perl does its own command line redirection, and
2675 thinks you tried to redirect stdout both to a file and into a pipe to another
2676 command. You need to choose one or the other, though nothing's stopping you
2677 from piping into a program or Perl script which 'splits' output into two
2680 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
2687 =item Got an error from DosAllocMem
2689 (P) An error peculiar to OS/2. Most probably you're using an obsolete
2690 version of Perl, and this should not happen anyway.
2692 =item Malformed PERLLIB_PREFIX
2694 (F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2702 with non-empty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2703 a builtin library search path, prefix2 is substituted. The error may appear
2704 if components are not found, or are too long. See L<perlos2/"PERLLIB_PREFIX">.
2706 =item PERL_SH_DIR too long
2708 (F) An error peculiar to OS/2. PERL_SH_DIR is the directory to find the
2709 C<sh>-shell in. See L<perlos2/"PERL_SH_DIR">.
2711 =item Process terminated by SIG%s
2713 (W) This is a standard message issued by OS/2 applications, while *nix
2714 applications die in silence. It is considered a feature of the OS/2
2715 port. One can easily disable this by appropriate sighandlers, see
2716 L<perlipc/"Signals">. See L<perlos2/"Process terminated by SIGTERM/SIGINT">.