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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
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).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
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18Optional warnings are enabled by using the B<-w> switch. Warnings may
19be captured by setting C<$^Q> to a reference to a routine that will be
20called on each warning instead of printing it. See L<perlvar>.
21Trappable errors may be trapped using the eval operator. See
22L<perlfunc/eval>.
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23
24Some of these messages are generic. Spots that vary are denoted with a %s,
25just as in a printf format. Note that some message start with a %s!
26The symbols C<"%-?@> sort before the letters, while C<[> and C<\> sort after.
27
28=over 4
29
30=item "my" variable %s can't be in a package
31
32(F) Lexically scoped variables aren't in a package, so it doesn't make sense
33to try to declare one with a package qualifier on the front. Use local()
34if you want to localize a package variable.
35
36=item "no" not allowed in expression
37
38(F) The "no" keyword is recognized and executed at compile time, and returns
39no useful value. See L<perlmod>.
40
41=item "use" not allowed in expression
42
43(F) The "use" keyword is recognized and executed at compile time, and returns
44no useful value. See L<perlmod>.
45
46=item % may only be used in unpack
47
48(F) You can't pack a string by supplying a checksum, since the
49checksumming process loses information, and you can't go the other
50way. See L<perlfunc/unpack>.
51
52=item %s (...) interpreted as function
53
54(W) You've run afoul of the rule that says that any list operator followed
55by parentheses turns into a function, with all the list operators arguments
56found inside the parens. See L<perlop/Terms and List Operators (Leftward)>.
57
58=item %s argument is not a HASH element
59
60(F) The argument to delete() or exists() must be a hash element, such as
61
62 $foo{$bar}
63 $ref->[12]->{"susie"}
64
65=item %s did not return a true value
66
67(F) A required (or used) file must return a true value to indicate that
68it compiled correctly and ran its initialization code correctly. It's
69traditional to end such a file with a "1;", though any true value would
70do. See L<perlfunc/require>.
71
72=item %s found where operator expected
73
74(S) The Perl lexer knows whether to expect a term or an operator. If it
75sees what it knows to be a term when it was expecting to see an operator,
76it gives you this warning. Usually it indicates that an operator or
77delimiter was omitted, such as a semicolon.
78
79=item %s had compilation errors.
80
81(F) The final summary message when a C<perl -c> fails.
82
83=item %s has too many errors.
84
85(F) The parser has given up trying to parse the program after 10 errors.
86Further error messages would likely be uninformative.
87
88=item %s matches null string many times
89
90(W) The pattern you've specified would be an infinite loop if the
91regular expression engine didn't specifically check for that. See L<perlre>.
92
93=item %s never introduced
94
95(S) The symbol in question was declared but somehow went out of scope
96before it could possibly have been used.
97
98=item %s syntax OK
99
100(F) The final summary message when a C<perl -c> succeeds.
101
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102=item %s: Command not found.
103
104(A) You've accidentally run your script through B<csh> instead
105of Perl. Check the <#!> line, or manually feed your script
106into Perl yourself.
107
108=item %s: Expression syntax.
109
110(A) You've accidentally run your script through B<csh> instead
111of Perl. Check the <#!> line, or manually feed your script
112into Perl yourself.
113
114=item %s: Undefined variable.
115
116(A) You've accidentally run your script through B<csh> instead
117of Perl. Check the <#!> line, or manually feed your script
118into Perl yourself.
119
120=item %s: not found
121
122(A) You've accidentally run your script through the Bourne shell
123instead of Perl. Check the <#!> line, or manually feed your script
124into Perl yourself.
125
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126=item B<-P> not allowed for setuid/setgid script
127
128(F) The script would have to be opened by the C preprocessor by name,
129which provides a race condition that breaks security.
130
131=item C<-T> and C<-B> not implemented on filehandles
132
133(F) Perl can't peek at the stdio buffer of filehandles when it doesn't
134know about your kind of stdio. You'll have to use a filename instead.
135
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136=item 500 Server error
137
138See Server error.
139
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140=item ?+* follows nothing in regexp
141
142(F) You started a regular expression with a quantifier. Backslash it
143if you meant it literally. See L<perlre>.
144
145=item @ outside of string
146
147(F) You had a pack template that specified an absolution position outside
148the string being unpacked. See L<perlfunc/pack>.
149
150=item accept() on closed fd
151
152(W) You tried to do an accept on a closed socket. Did you forget to check
153the return value of your socket() call? See L<perlfunc/accept>.
154
155=item Allocation too large: %lx
156
157(F) You can't allocate more than 64K on an MSDOS machine.
158
159=item Arg too short for msgsnd
160
161(F) msgsnd() requires a string at least as long as sizeof(long).
162
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163=item Ambiguous use of %s resolved as %s
164
165(W)(S) You said something that may not be interpreted the way
166you thought. Normally it's pretty easy to disambiguate it by supplying
167a missing quote, operator, paren pair or declaration.
168
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169=item Args must match #! line
170
171(F) The setuid emulator requires that the arguments Perl was invoked
172with match the arguments specified on the #! line.
173
174=item Argument "%s" isn't numeric
175
176(W) The indicated string was fed as an argument to an operator that
177expected a numeric value instead. If you're fortunate the message
178will identify which operator was so unfortunate.
179
180=item Array @%s missing the @ in argument %d of %s()
181
182(D) Really old Perl let you omit the @ on array names in some spots. This
183is now heavily deprecated.
184
185=item assertion botched: %s
186
187(P) The malloc package that comes with Perl had an internal failure.
188
189=item Assertion failed: file "%s"
190
191(P) A general assertion failed. The file in question must be examined.
192
193=item Assignment to both a list and a scalar
194
195(F) If you assign to a conditional operator, the 2nd and 3rd arguments
196must either both be scalars or both be lists. Otherwise Perl won't
197know which context to supply to the right side.
198
199=item Attempt to free non-arena SV: 0x%lx
200
201(P) All SV objects are supposed to be allocated from arenas that will
202be garbage collected on exit. An SV was discovered to be outside any
203of those arenas.
204
205=item Attempt to free temp prematurely
206
207(W) Mortalized values are supposed to be freed by the free_tmps()
208routine. This indicates that something else is freeing the SV before
209the free_tmps() routine gets a chance, which means that the free_tmps()
210routine will be freeing an unreferenced scalar when it does try to free
211it.
212
213=item Attempt to free unreferenced glob pointers
214
215(P) The reference counts got screwed up on symbol aliases.
216
217=item Attempt to free unreferenced scalar
218
219(W) Perl went to decrement the reference count of a scalar to see if it
220would go to 0, and discovered that it had already gone to 0 earlier,
221and should have been freed, and in fact, probably was freed. This
222could indicate that SvREFCNT_dec() was called too many times, or that
223SvREFCNT_inc() was called too few times, or that the SV was mortalized
224when it shouldn't have been, or that memory has been corrupted.
225
226=item Bad arg length for %s, is %d, should be %d
227
228(F) You passed a buffer of the wrong size to one of msgctl(), semctl() or
229shmctl(). In C parlance, the correct sized are, respectively,
230S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)> and
231S<sizeof(struct shmid_ds *)>.
232
233=item Bad associative array
234
235(P) One of the internal hash routines was passed a null HV pointer.
236
237=item Bad filehandle: %s
238
239(F) A symbol was passed to something wanting a filehandle, but the symbol
240has no filehandle associated with it. Perhaps you didn't do an open(), or
241did it in another package.
242
243=item Bad free() ignored
244
245(S) An internal routine called free() on something that had never been
246malloc()ed in the first place.
247
248=item Bad name after %s::
249
250(F) You started to name a symbol by using a package prefix, and then didn't
251finish the symbol. In particular, you can't interpolate outside of quotes,
252so
253
254 $var = 'myvar';
255 $sym = mypack::$var;
256
257is not the same as
258
259 $var = 'myvar';
260 $sym = "mypack::$var";
261
262=item Bad symbol for array
263
264(P) An internal request asked to add an array entry to something that
265wasn't a symbol table entry.
266
267=item Bad symbol for filehandle
268
269(P) An internal request asked to add a filehandle entry to something that
270wasn't a symbol table entry.
271
272=item Bad symbol for hash
273
274(P) An internal request asked to add a hash entry to something that
275wasn't a symbol table entry.
276
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277=item Badly places ()'s
278
279(A) You've accidentally run your script through B<csh> instead
280of Perl. Check the <#!> line, or manually feed your script
281into Perl yourself.
282
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283=item BEGIN failed--compilation aborted
284
285(F) An untrapped exception was raised while executing a BEGIN subroutine.
286Compilation stops immediately and the interpreter is exited.
287
288=item bind() on closed fd
289
290(W) You tried to do a bind on a closed socket. Did you forget to check
291the return value of your socket() call? See L<perlfunc/bind>.
292
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293=item Bizarre copy of %s in %s
294
295(P) Perl detected an attempt to copy an internal value that is not copiable.
296
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297=item Callback called exit
298
299(F) A subroutine invoked from an external package via perl_call_sv()
300exited by calling exit.
301
302=item Can't "last" outside a block
303
304(F) A "last" statement was executed to break out of the current block,
305except that there's this itty bitty problem called there isn't a
306current block. Note that an "if" or "else" block doesn't count as a
307"loopish" block. You can usually double the curlies to get the same
308effect though, since the inner curlies will be considered a block
309that loops once. See L<perlfunc/last>.
310
311=item Can't "next" outside a block
312
313(F) A "next" statement was executed to reiterate the current block, but
314there isn't a current block. Note that an "if" or "else" block doesn't
315count as a "loopish" block. You can usually double the curlies to get
316the same effect though, since the inner curlies will be considered a block
317that loops once. See L<perlfunc/last>.
318
319=item Can't "redo" outside a block
320
321(F) A "redo" statement was executed to restart the current block, but
322there isn't a current block. Note that an "if" or "else" block doesn't
323count as a "loopish" block. You can usually double the curlies to get
324the same effect though, since the inner curlies will be considered a block
325that loops once. See L<perlfunc/last>.
326
327=item Can't bless non-reference value
328
329(F) Only hard references may be blessed. This is how Perl "enforces"
330encapsulation of objects. See L<perlobj>.
331
332=item Can't break at that line
333
334(S) A warning intended for while running within the debugger, indicating
335the line number specified wasn't the location of a statement that could
336be stopped at.
337
338=item Can't call method "%s" in empty package "%s"
339
340(F) You called a method correctly, and it correctly indicated a package
341functioning as a class, but that package doesn't have ANYTHING defined
342in it, let alone methods. See L<perlobj>.
343
344=item Can't call method "%s" on unblessed reference
345
346(F) A method call must know what package it's supposed to run in. It
347ordinarily finds this out from the object reference you supply, but
348you didn't supply an object reference in this case. A reference isn't
349an object reference until it has been blessed. See L<perlobj>.
350
351=item Can't call method "%s" without a package or object reference
352
353(F) You used the syntax of a method call, but the slot filled by the
354object reference or package name contains an expression that returns
355neither an object reference nor a package name. (Perhaps it's null?)
356Something like this will reproduce the error:
357
358 $BADREF = undef;
359 process $BADREF 1,2,3;
360 $BADREF->process(1,2,3);
361
362=item Can't chdir to %s
363
364(F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
365that you can chdir to, possibly because it doesn't exist.
366
367=item Can't coerce %s to integer in %s
368
369(F) Certain types of SVs, in particular real symbol table entries
370(type GLOB), can't be forced to stop being what they are. So you can't
371say things like:
372
373 *foo += 1;
374
375You CAN say
376
377 $foo = *foo;
378 $foo += 1;
379
380but then $foo no longer contains a glob.
381
382=item Can't coerce %s to number in %s
383
384(F) Certain types of SVs, in particular real symbol table entries
385(type GLOB), can't be forced to stop being what they are.
386
387=item Can't coerce %s to string in %s
388
389(F) Certain types of SVs, in particular real symbol table entries
390(type GLOB), can't be forced to stop being what they are.
391
392=item Can't create pipe mailbox
393
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394(P) An error peculiar to VMS. The process is suffering from exhausted quotas
395or other plumbing problems.
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396
397=item Can't declare %s in my
398
399(F) Only scalar, array and hash variables may be declared as lexical variables.
400They must have ordinary identifiers as names.
401
402=item Can't do inplace edit on %s: %s
403
404(S) The creation of the new file failed for the indicated reason.
405
406=item Can't do inplace edit without backup
407
408(F) You're on a system such as MSDOS that gets confused if you try reading
409from a deleted (but still opened) file. You have to say B<-i>C<.bak>, or some
410such.
411
412=item Can't do inplace edit: %s > 14 characters
413
414(S) There isn't enough room in the filename to make a backup name for the file.
415
416=item Can't do inplace edit: %s is not a regular file
417
418(S) You tried to use the B<-i> switch on a special file, such as a file in
419/dev, or a FIFO. The file was ignored.
420
421=item Can't do setegid!
422
423(P) The setegid() call failed for some reason in the setuid emulator
424of suidperl.
425
426=item Can't do seteuid!
427
428(P) The setuid emulator of suidperl failed for some reason.
429
430=item Can't do setuid
431
432(F) This typically means that ordinary perl tried to exec suidperl to
433do setuid emulation, but couldn't exec it. It looks for a name of the
434form sperl5.000 in the same directory that the perl executable resides
435under the name perl5.000, typically /usr/local/bin on Unix machines.
436If the file is there, check the execute permissions. If it isn't, ask
437your sysadmin why he and/or she removed it.
438
439=item Can't do waitpid with flags
440
441(F) This machine doesn't have either waitpid() or wait4(), so only waitpid()
442without flags is emulated.
443
444=item Can't do {n,m} with n > m
445
446(F) Minima must be less than or equal to maxima. If you really want
447your regexp to match something 0 times, just put {0}. See L<perlre>.
448
449=item Can't emulate -%s on #! line
450
451(F) The #! line specifies a switch that doesn't make sense at this point.
452For example, it'd be kind of silly to put a B<-x> on the #! line.
453
454=item Can't exec "%s": %s
455
456(W) An system(), exec() or piped open call could not execute the named
457program for the indicated reason. Typical reasons include: the permissions
458were wrong on the file, the file wasn't found in C<$ENV{PATH}>, the
459executable in question was compiled for another architecture, or the
460#! line in a script points to an interpreter that can't be run for
461similar reasons. (Or maybe your system doesn't support #! at all.)
462
463=item Can't exec %s
464
465(F) Perl was trying to execute the indicated program for you because that's
466what the #! line said. If that's not what you wanted, you may need to
467mention "perl" on the #! line somewhere.
468
469=item Can't execute %s
470
471(F) You used the B<-S> switch, but the script to execute could not be found
472in the PATH, or at least not with the correct permissions.
473
474=item Can't find label %s
475
476(F) You said to goto a label that isn't mentioned anywhere that it's possible
477for us to go to. See L<perlfunc/goto>.
478
479=item Can't find string terminator %s anywhere before EOF
480
481(F) Perl strings can stretch over multiple lines. This message means that
482the closing delimiter was omitted. Since bracketed quotes count nesting
483levels, the following is missing its final parenthesis:
484
485 print q(The character '(' starts a side comment.)
486
487=item Can't fork
488
489(F) A fatal error occurred while trying to fork while opening a pipeline.
490
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491=item Can't get filespec - stale stat buffer?
492
493(S) A warning peculiar to VMS. This arises because of the difference between
494access checks under VMS and under the Unix model Perl assumes. Under VMS,
495access checks are done by filename, rather than by bits in the stat buffer, so
496that ACLs and other protections can be taken into account. Unfortunately, Perl
497assumes that the stat buffer contains all the necessary information, and passes
498it, instead of the filespec, to the access checking routine. It will try to
499retrieve the filespec using the device name and FID present in the stat buffer,
500but this works only if you haven't made a subsequent call to the CRTL stat()
501routine, since the device name is overwritten with each call. If this warning
502appears, the name lookup failed, and the access checking routine gave up and
503returned FALSE, just to be conservative. (Note: The access checking routine
504knows about the Perl C<stat> operator and file tests, so you shouldn't ever
505see this warning in response to a Perl command; it arises only if some internal
506code takes stat buffers lightly.)
507
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508=item Can't get pipe mailbox device name
509
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510(P) An error peculiar to VMS. After creating a mailbox to act as a pipe, Perl
511can't retrieve its name for later use.
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512
513=item Can't get SYSGEN parameter value for MAXBUF
514
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515(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
516mailbox buffers to be, and didn't get an answer.
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517
518=item Can't goto subroutine outside a subroutine
519
520(F) The deeply magical "goto subroutine" call can only replace one subroutine
521call for another. It can't manufacture one out of whole cloth. In general
522you should only be calling it out of an AUTOLOAD routine anyway. See
523L<perlfunc/goto>.
524
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525=item Can't localize a reference
526
527(F) You said something like C<local $$ref>, which is not allowed because
528the compiler can't determine whether $ref will end up pointing to anything
529with a symbol table entry, and a symbol table entry is necessary to
530do a local.
531
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532=item Can't localize lexical variable %s
533
534(F) You used local on a variable name that was previous declared as a
535lexical variable using "my". This is not allowed. If you want to
536localize a package variable of the same name, qualify it with the
537package name.
538
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539=item Can't locate %s in @INC
540
541(F) You said to do (or require, or use) a file that couldn't be found
542in any of the libraries mentioned in @INC. Perhaps you need to set
543the PERL5LIB environment variable to say where the extra library is,
544or maybe the script needs to add the library name to @INC. Or maybe
545you just misspelled the name of the file. See L<perlfunc/require>.
546
547=item Can't locate object method "%s" via package "%s"
548
549(F) You called a method correctly, and it correctly indicated a package
550functioning as a class, but that package doesn't define that particular
551method, nor does any of it's base classes. See L<perlobj>.
552
553=item Can't locate package %s for @%s::ISA
554
555(W) The @ISA array contained the name of another package that doesn't seem
556to exist.
557
558=item Can't mktemp()
559
560(F) The mktemp() routine failed for some reason while trying to process
561a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
562
563=item Can't modify %s in %s
564
565(F) You aren't allowed to assign to the item indicated, or otherwise try to
566change it, such as with an autoincrement.
567
568=item Can't modify non-existent substring
569
570(P) The internal routine that does assignment to a substr() was handed
571a NULL.
572
573=item Can't msgrcv to readonly var
574
575(F) The target of a msgrcv must be modifiable in order to be used as a receive
576buffer.
577
578=item Can't open %s: %s
579
580(S) An inplace edit couldn't open the original file for the indicated reason.
581Usually this is because you don't have read permission for the file.
582
583=item Can't open bidirectional pipe
584
585(W) You tried to say C<open(CMD, "|cmd|")>, which is not supported. You can
586try any of several modules in the Perl library to do this, such as
587"open2.pl". Alternately, direct the pipe's output to a file using ">",
588and then read it in under a different file handle.
589
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590=item Can't open error file %s as stderr
591
592(F) An error peculiar to VMS. Perl does its own command line redirection, and
593couldn't open the file specified after '2>' or '2>>' on the command line for
594writing.
595
596=item Can't open input file %s as stdin
597
598(F) An error peculiar to VMS. Perl does its own command line redirection, and
599couldn't open the file specified after '<' on the command line for reading.
600
601=item Can't open output file %s as stdout
602
603(F) An error peculiar to VMS. Perl does its own command line redirection, and
604couldn't open the file specified after '>' or '>>' on the command line for
605writing.
606
607=item Can't open output pipe (name: %s)
608
609(P) An error peculiar to VMS. Perl does its own command line redirection, and
610couldn't open the pipe into which to send data destined for stdout.
611
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612=item Can't open perl script "%s": %s
613
614(F) The script you specified can't be opened for the indicated reason.
615
616=item Can't rename %s to %s: %s, skipping file
617
618(S) The rename done by the B<-i> switch failed for some reason, probably because
619you don't have write permission to the directory.
620
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621=item Can't reopen input pipe (name: %s) in binary mode
622
623(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried to
624reopen it to accept binary data. Alas, it failed.
625
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626=item Can't reswap uid and euid
627
628(P) The setreuid() call failed for some reason in the setuid emulator
629of suidperl.
630
631=item Can't return outside a subroutine
632
633(F) The return statement was executed in mainline code, that is, where
634there was no subroutine call to return out of. See L<perlsub>.
635
636=item Can't stat script "%s"
637
638(P) For some reason you can't fstat() the script even though you have
639it open already. Bizarre.
640
641=item Can't swap uid and euid
642
643(P) The setreuid() call failed for some reason in the setuid emulator
644of suidperl.
645
646=item Can't take log of %g
647
648(F) Logarithms are only defined on positive real numbers.
649
650=item Can't take sqrt of %g
651
652(F) For ordinary real numbers, you can't take the square root of a
653negative number. There's a Complex package available for Perl, though,
654if you really want to do that.
655
656=item Can't undef active subroutine
657
658(F) You can't undefine a routine that's currently running. You can,
659however, redefine it while it's running, and you can even undef the
660redefined subroutine while the old routine is running. Go figure.
661
662=item Can't unshift
663
664(F) You tried to unshift an "unreal" array that can't be unshifted, such
665as the main Perl stack.
666
667=item Can't upgrade that kind of scalar
668
669(P) The internal sv_upgrade routine adds "members" to an SV, making
670it into a more specialized kind of SV. The top several SV types are
671so specialized, however, that they cannot be interconverted. This
672message indicates that such a conversion was attempted.
673
674=item Can't upgrade to undef
675
676(P) The undefined SV is the bottom of the totem pole, in the scheme
677of upgradability. Upgrading to undef indicates an error in the
678code calling sv_upgrade.
679
c07a80fd
PP
680=item Can't use "my %s" in sort comparison
681
682(F) The global variables $a and $b are reserved for sort comparisons.
683You mentioned $a or $b in the same line as the <=> or cmp operator,
684and the variable had earlier been declared as a lexical variable.
685Either qualify the sort variable with the package name, or rename the
686lexical variable.
687
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LW
688=item Can't use %s for loop variable
689
690(F) Only a simple scalar variable may be used as a loop variable on a foreach.
691
692=item Can't use %s ref as %s ref
693
694(F) You've mixed up your reference types. You have to dereference a
695reference of the type needed. You can use the ref() function to
696test the type of the reference, if need be.
697
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LW
698=item Can't use \1 to mean $1 in expression
699
700(W) In an ordinary expression, backslash is a unary operator that creates
701a reference to its argument. The use of backslash to indicate a backreference
702to a matched substring is only valid as part of a regular expression pattern.
703Trying to do this in ordinary Perl code produces a value that prints
704out looking like SCALAR(0xdecaf). Use the $1 form instead.
705
706=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e
LW
707
708(F) Only hard references are allowed by "strict refs". Symbolic references
709are disallowed. See L<perlref>.
710
711=item Can't use an undefined value as %s reference
712
713(F) A value used as either a hard reference or a symbolic reference must
714be a defined value. This helps to de-lurk some insidious errors.
715
716=item Can't use delimiter brackets within expression
717
718(F) The ${name} construct is for disambiguating identifiers in strings, not
719in ordinary code.
720
721=item Can't use global %s in "my"
722
723(F) You tried to declare a magical variable as a lexical variable. This is
724not allowed, because the magic can only be tied to one location (namely
725the global variable) and it would be incredibly confusing to have
726variables in your program that looked like magical variables but
727weren't.
728
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LW
729=item Can't use subscript on %s
730
731(F) The compiler tried to interpret a bracketed expression as a
732subscript. But to the left of the brackets was an expression that
733didn't look like an array reference, or anything else subscriptable.
734
a0d0e21e
LW
735=item Can't write to temp file for B<-e>: %s
736
737(F) The write routine failed for some reason while trying to process
738a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
739
740=item Can't x= to readonly value
741
742(F) You tried to repeat a constant value (often the undefined value) with
743an assignment operator, which implies modifying the value itself.
744Perhaps you need to copy the value to a temporary, and repeat that.
745
746=item Cannot open temporary file
747
748(F) The create routine failed for some reaon while trying to process
749a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
750
751=item chmod: mode argument is missing initial 0
752
753(W) A novice will sometimes say
754
755 chmod 777, $filename
756
757not realizing that 777 will be interpreted as a decimal number, equivalent
758to 01411. Octal constants are introduced with a leading 0 in Perl, as in C.
759
760=item Close on unopened file <%s>
761
762(W) You tried to close a filehandle that was never opened.
763
764=item connect() on closed fd
765
766(W) You tried to do a connect on a closed socket. Did you forget to check
767the return value of your socket() call? See L<perlfunc/connect>.
768
769=item Corrupt malloc ptr 0x%lx at 0x%lx
770
771(P) The malloc package that comes with Perl had an internal failure.
772
773=item corrupted regexp pointers
774
775(P) The regular expression engine got confused by what the regular
776expression compiler gave it.
777
778=item corrupted regexp program
779
780(P) The regular expression engine got passed a regexp program without
781a valid magic number.
782
783=item Deep recursion on subroutine "%s"
784
785(W) This subroutine has called itself (directly or indirectly) 100
786times than it has returned. This probably indicates an infinite
787recursion, unless you're writing strange benchmark programs, in which
788case it indicates something else.
789
4633a7c4
LW
790=item Did you mean &%s instead?
791
792(W) You probably referred to an imported subroutine &FOO as $FOO or some such.
793
748a9306 794=item Did you mean $ or @ instead of %?
a0d0e21e 795
748a9306
LW
796(W) You probably said %hash{$key} when you meant $hash{$key} or @hash{@keys}.
797On the other hand, maybe you just meant %hash and got carried away.
798
799=item Do you need to predeclare %s?
800
801(S) This is an educated guess made in conjunction with the message "%s
802found where operator expected". It often means a subroutine or module
803name is being referenced that hasn't been declared yet. This may be
804because of ordering problems in your file, or because of a missing
805"sub", "package", "require", or "use" statement. If you're
806referencing something that isn't defined yet, you don't actually have
807to define the subroutine or package before the current location. You
808can use an empty "sub foo;" or "package FOO;" to enter a "forward"
809declaration.
a0d0e21e
LW
810
811=item Don't know how to handle magic of type '%s'
812
813(P) The internal handling of magical variables has been cursed.
814
815=item do_study: out of memory
816
817(P) This should have been caught by safemalloc() instead.
818
819=item Duplicate free() ignored
820
821(S) An internal routine called free() on something that had already
822been freed.
823
4633a7c4
LW
824=item elseif should be elsif
825
826(S) There is no keyword "elseif" in Perl because Larry thinks it's
827ugly. Your code will be interpreted as an attempt to call a method
828named "elseif" for the class returned by the following block. This is
829unlikely to be what you want.
830
a0d0e21e
LW
831=item END failed--cleanup aborted
832
833(F) An untrapped exception was raised while executing an END subroutine.
834The interpreter is immediately exited.
835
748a9306
LW
836=item Error converting file specification %s
837
838(F) An error peculiar to VMS. Since Perl may have to deal with file
839specifications in either VMS or Unix syntax, it converts them to a
840single form when it must operate on them directly. Either you've
841passed an invalid file specification to Perl, or you've found a
842case the conversion routines don't handle. Drat.
843
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LW
844=item Execution of %s aborted due to compilation errors.
845
846(F) The final summary message when a Perl compilation fails.
847
848=item Exiting eval via %s
849
850(W) You are exiting an eval by unconventional means, such as a
851a goto, or a loop control statement.
852
853=item Exiting subroutine via %s
854
855(W) You are exiting a subroutine by unconventional means, such as a
856a goto, or a loop control statement.
857
858=item Exiting substitution via %s
859
860(W) You are exiting a substitution by unconventional means, such as a
861a return, a goto, or a loop control statement.
862
748a9306 863=item Fatal VMS error at %s, line %d
a0d0e21e 864
748a9306
LW
865(P) An error peculiar to VMS. Something untoward happened in a VMS system
866service or RTL routine; Perl's exit status should provide more details. The
867filename in "at %s" and the line number in "line %d" tell you which section of
868the Perl source code is distressed.
a0d0e21e
LW
869
870=item fcntl is not implemented
871
872(F) Your machine apparently doesn't implement fcntl(). What is this, a
873PDP-11 or something?
874
875=item Filehandle %s never opened
876
877(W) An I/O operation was attempted on a filehandle that was never initialized.
878You need to do an open() or a socket() call, or call a constructor from
879the FileHandle package.
880
881=item Filehandle %s opened only for input
882
883(W) You tried to write on a read-only filehandle. If you
884intended it to be a read-write filehandle, you needed to open it with
885"+<" or "+>" or "+>>" instead of with "<" or nothing. If you only
886intended to write the file, use ">" or ">>". See L<perlfunc/open>.
887
888=item Filehandle only opened for input
889
890(W) You tried to write on a read-only filehandle. If you
891intended it to be a read-write filehandle, you needed to open it with
892"+<" or "+>" or "+>>" instead of with "<" or nothing. If you only
893intended to write the file, use ">" or ">>". See L<perlfunc/open>.
894
895=item Final $ should be \$ or $name
896
897(F) You must now decide whether the final $ in a string was meant to be
898a literal dollar sign, or was meant to introduce a variable name
899that happens to be missing. So you have to put either the backslash or
900the name.
901
902=item Final @ should be \@ or @name
903
904(F) You must now decide whether the final @ in a string was meant to be
905a literal "at" sign, or was meant to introduce a variable name
906that happens to be missing. So you have to put either the backslash or
907the name.
908
909=item Format %s redefined
910
911(W) You redefined a format. To suppress this warning, say
912
913 {
914 local $^W = 0;
915 eval "format NAME =...";
916 }
917
918=item Format not terminated
919
920(F) A format must be terminated by a line with a solitary dot. Perl got
921to the end of your file without finding such a line.
922
923=item Found = in conditional, should be ==
924
925(W) You said
926
927 if ($foo = 123)
928
929when you meant
930
931 if ($foo == 123)
932
933(or something like that).
934
935=item gdbm store returned %d, errno %d, key "%s"
936
937(S) A warning from the GDBM_File extension that a store failed.
938
939=item gethostent not implemented
940
941(F) Your C library apparently doesn't implement gethostent(), probably
942because if it did, it'd feel morally obligated to return every hostname
943on the Internet.
944
945=item get{sock,peer}name() on closed fd
946
947(W) You tried to get a socket or peer socket name on a closed socket.
948Did you forget to check the return value of your socket() call?
949
748a9306
LW
950=item getpwnam returned invalid UIC %#o for user "%s"
951
952(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
953C<getpwnam> operator returned an invalid UIC.
954
955
a0d0e21e
LW
956=item Glob not terminated
957
958(F) The lexer saw a left angle bracket in a place where it was expecting
959a term, so it's looking for the corresponding right angle bracket, and not
960finding it. Chances are you left some needed parentheses out earlier in
961the line, and you really meant a "less than".
962
963=item Global symbol "%s" requires explicit package name
964
965(F) You've said "use strict vars", which indicates that all variables must
966either be lexically scoped (using "my"), or explicitly qualified to
967say which package the global variable is in (using "::").
968
969=item goto must have label
970
971(F) Unlike with "next" or "last", you're not allowed to goto an
972unspecified destination. See L<perlfunc/goto>.
973
974=item Had to create %s unexpectedly
975
976(S) A routine asked for a symbol from a symbol table that ought to have
977existed already, but for some reason it didn't, and had to be created on
978an emergency basis to prevent a core dump.
979
980=item Hash %%s missing the % in argument %d of %s()
981
982(D) Really old Perl let you omit the % on hash names in some spots. This
983is now heavily deprecated.
984
985=item Identifier "%s::%s" used only once: possible typo
986
987(W) Typographical errors often show up as unique identifiers. If you
988had a good reason for having a unique identifier, then just mention it
989again somehow to suppress the message.
990
991=item Illegal division by zero
992
993(F) You tried to divide a number by 0. Either something was wrong in your
994logic, or you need to put a conditional in to guard against meaningless input.
995
996=item Illegal modulus zero
997
998(F) You tried to divide a number by 0 to get the remainder. Most numbers
999don't take to this kindly.
1000
1001=item Illegal octal digit
1002
1003(F) You used an 8 or 9 in a octal number.
1004
748a9306
LW
1005=item Illegal octal digit ignored
1006
1007(W) You may have tried to use an 8 or 9 in a octal number. Interpretation
1008of the octal number stopped before the 8 or 9.
1009
a0d0e21e
LW
1010=item Insecure dependency in %s
1011
1012(F) You tried to do something that the tainting mechanism didn't like.
1013The tainting mechanism is turned on when you're running setuid or setgid,
1014or when you specify B<-T> to turn it on explicitly. The tainting mechanism
1015labels all data that's derived directly or indirectly from the user,
1016who is considered to be unworthy of your trust. If any such data is
1017used in a "dangerous" operation, you get this error. See L<perlsec>
1018for more information.
1019
1020=item Insecure directory in %s
1021
1022(F) You can't use system(), exec(), or a piped open in a setuid or setgid
1023script if $ENV{PATH} contains a directory that is writable by the world.
1024See L<perlsec>.
1025
1026=item Insecure PATH
1027
1028(F) You can't use system(), exec(), or a piped open in a setuid or
1029setgid script if $ENV{PATH} is derived from data supplied (or
1030potentially supplied) by the user. The script must set the path to a
1031known value, using trustworthy data. See L<perlsec>.
1032
748a9306
LW
1033=item Internal inconsistency in tracking vforks
1034
1035(S) A warning peculiar to VMS. Perl keeps track of the number
1036of times you've called C<fork> and C<exec>, in order to determine
1037whether the current call to C<exec> should be affect the current
1038script or a subprocess (see L<perlvms/exec>). Somehow, this count
1039has become scrambled, so Perl is making a guess and treating
1040this C<exec> as a request to terminate the Perl script
1041and execute the specified command.
1042
a0d0e21e
LW
1043=item internal disaster in regexp
1044
1045(P) Something went badly wrong in the regular expression parser.
1046
1047=item internal urp in regexp at /%s/
1048
1049(P) Something went badly awry in the regular expression parser.
1050
1051=item invalid [] range in regexp
1052
1053(F) The range specified in a character class had a minimum character
1054greater than the maximum character. See L<perlre>.
1055
1056=item ioctl is not implemented
1057
1058(F) Your machine apparently doesn't implement ioctl(), which is pretty
1059strange for a machine that supports C.
1060
1061=item junk on end of regexp
1062
1063(P) The regular expression parser is confused.
1064
1065=item Label not found for "last %s"
1066
1067(F) You named a loop to break out of, but you're not currently in a
1068loop of that name, not even if you count where you were called from.
1069See L<perlfunc/last>.
1070
1071=item Label not found for "next %s"
1072
1073(F) You named a loop to continue, but you're not currently in a loop of
1074that name, not even if you count where you were called from. See
1075L<perlfunc/last>.
1076
1077=item Label not found for "redo %s"
1078
1079(F) You named a loop to restart, but you're not currently in a loop of
1080that name, not even if you count where you were called from. See
1081L<perlfunc/last>.
1082
1083=item listen() on closed fd
1084
1085(W) You tried to do a listen on a closed socket. Did you forget to check
1086the return value of your socket() call? See L<perlfunc/listen>.
1087
1088=item Literal @%s now requires backslash
1089
1090(F) It used to be that Perl would try to guess whether you wanted an
1091array interpolated or a literal @. It did this when the string was
1092first used at runtime. Now strings are parsed at compile time, and
1093ambiguous instances of @ must be disambiguated, either by putting a
1094backslash to indicate a literal, or by declaring (or using) the array
1095within the program before the string (lexically). (Someday it will simply
1096assume that an unbackslashed @ interpolates an array.)
1097
1098=item Method for operation %s not found in package %s during blessing
1099
1100(F) An attempt was made to specify an entry in an overloading table that
1101doesn't somehow point to a valid method. See L<perlovl>.
1102
1103=item Might be a runaway multi-line %s string starting on line %d
1104
1105(S) An advisory indicating that the previous error may have been caused
1106by a missing delimiter on a string or pattern, because it eventually
1107ended earlier on the current line.
1108
1109=item Misplaced _ in number
1110
1111(W) An underline in a decimal constant wasn't on a 3-digit boundary.
1112
1113=item Missing $ on loop variable
1114
1115(F) Apparently you've been programming in csh too much. Variables are always
1116mentioned with the $ in Perl, unlike in the shells, where it can vary from
1117one line to the next.
1118
1119=item Missing comma after first argument to %s function
1120
1121(F) While certain functions allow you to specify a filehandle or an
1122"indirect object" before the argument list, this ain't one of them.
1123
748a9306
LW
1124=item Missing operator before %s?
1125
1126(S) This is an educated guess made in conjunction with the message "%s
1127found where operator expected". Often the missing operator is a comma.
1128
a0d0e21e
LW
1129=item Missing right bracket
1130
1131(F) The lexer counted more opening curly brackets (braces) than closing ones.
1132As a general rule, you'll find it's missing near the place you were last
1133editing.
1134
1135=item Missing semicolon on previous line?
1136
1137(S) This is an educated guess made in conjunction with the message "%s
1138found where operator expected". Don't automatically put a semicolon on
1139the previous line just because you saw this message.
1140
1141=item Modification of a read-only value attempted
1142
1143(F) You tried, directly or indirectly, to change the value of a
1144constant. You didn't, of course, try "2 = 1", since the compiler
1145catches that. But an easy way to do the same thing is:
1146
1147 sub mod { $_[0] = 1 }
1148 mod(2);
1149
1150Another way is to assign to a substr() that's off the end of the string.
1151
1152=item Modification of non-creatable array value attempted, subscript %d
1153
1154(F) You tried to make an array value spring into existence, and the
1155subscript was probably negative, even counting from end of the array
1156backwards.
1157
1158=item Modification of non-creatable hash value attempted, subscript "%s"
1159
1160(F) You tried to make a hash value spring into existence, and it couldn't
1161be created for some peculiar reason.
1162
1163=item Module name must be constant
1164
1165(F) Only a bare module name is allowed as the first argument to a "use".
1166
1167=item msg%s not implemented
1168
1169(F) You don't have System V message IPC on your system.
1170
1171=item Multidimensional syntax %s not supported
1172
1173(W) Multidimensional arrays aren't written like $foo[1,2,3]. They're written
1174like $foo[1][2][3], as in C.
1175
1176=item Negative length
1177
1178(F) You tried to do a read/write/send/recv operation with a buffer length
1179that is less than 0. This is difficult to imagine.
1180
1181=item nested *?+ in regexp
1182
1183(F) You can't quantify a quantifier without intervening parens. So
1184things like ** or +* or ?* are illegal.
1185
1186Note, however, that the minimal matching quantifiers, *?, +? and ?? appear
1187to be nested quantifiers, but aren't. See L<perlre>.
1188
1189=item No #! line
1190
1191(F) The setuid emulator requires that scripts have a well-formed #! line
1192even on machines that don't support the #! construct.
1193
1194=item No %s allowed while running setuid
1195
1196(F) Certain operations are deemed to be too insecure for a setuid or setgid
1197script to even be allowed to attempt. Generally speaking there will be
1198another way to do what you want that is, if not secure, at least securable.
1199See L<perlsec>.
1200
1201=item No B<-e> allowed in setuid scripts
1202
1203(F) A setuid script can't be specified by the user.
1204
1205=item No comma allowed after %s
1206
1207(F) A list operator that has a filehandle or "indirect object" is not
1208allowed to have a comma between that and the following arguments.
1209Otherwise it'd be just another one of the arguments.
1210
748a9306
LW
1211=item No command into which to pipe on command line
1212
1213(F) An error peculiar to VMS. Perl handles its own command line redirection,
1214and found a '|' at the end of the command line, so it doesn't know whither you
1215want to pipe the output from this command.
1216
a0d0e21e
LW
1217=item No DB::DB routine defined
1218
1219(F) The currently executing code was compiled with the B<-d> switch,
1220but for some reason the perl5db.pl file (or some facsimile thereof)
1221didn't define a routine to be called at the beginning of each
1222statement. Which is odd, because the file should have been required
1223automatically, and should have blown up the require if it didn't parse
1224right.
1225
1226=item No dbm on this machine
1227
1228(P) This is counted as an internal error, because every machine should
1229supply dbm nowadays, since Perl comes with SDBM. See L<SDBM_File>.
1230
1231=item No DBsub routine
1232
1233(F) The currently executing code was compiled with the B<-d> switch,
1234but for some reason the perl5db.pl file (or some facsimile thereof)
1235didn't define a DB::sub routine to be called at the beginning of each
1236ordinary subroutine call.
1237
748a9306
LW
1238=item No error file after 2> or 2>> on command line
1239
1240(F) An error peculiar to VMS. Perl handles its own command line redirection,
1241and found a '2>' or a '2>>' on the command line, but can't find the name of the
1242file to which to write data destined for stderr.
1243
1244=item No input file after < on command line
1245
1246(F) An error peculiar to VMS. Perl handles its own command line redirection,
1247and found a '<' on the command line, but can't find the name of the file from
1248which to read data for stdin.
1249
1250=item No output file after > on command line
1251
1252(F) An error peculiar to VMS. Perl handles its own command line redirection,
1253and found a lone '>' at the end of the command line, so it doesn't know whither
1254you wanted to redirect stdout.
1255
1256=item No output file after > or >> on command line
1257
1258(F) An error peculiar to VMS. Perl handles its own command line redirection,
1259and found a '>' or a '>>' on the command line, but can't find the name of the
1260file to which to write data destined for stdout.
1261
a0d0e21e
LW
1262=item No Perl script found in input
1263
1264(F) You called C<perl -x>, but no line was found in the file beginning
1265with #! and containing the word "perl".
1266
1267=item No setregid available
1268
1269(F) Configure didn't find anything resembling the setregid() call for
1270your system.
1271
1272=item No setreuid available
1273
1274(F) Configure didn't find anything resembling the setreuid() call for
1275your system.
1276
1277=item No space allowed after B<-I>
1278
1279(F) The argument to B<-I> must follow the B<-I> immediately with no
1280intervening space.
1281
748a9306
LW
1282=item No such pipe open
1283
1284(P) An error peculiar to VMS. The internal routine my_pclose() tried to
1285close a pipe which hadn't been opened. This should have been caught earlier as
1286an attempt to close an unopened filehandle.
1287
a0d0e21e
LW
1288=item No such signal: SIG%s
1289
1290(W) You specified a signal name as a subscript to %SIG that was not recognized.
1291Say C<kill -l> in your shell to see the valid signal names on your system.
1292
1293=item Not a CODE reference
1294
1295(F) Perl was trying to evaluate a reference to a code value (that is, a
1296subroutine), but found a reference to something else instead. You can
1297use the ref() function to find out what kind of ref it really was.
1298See also L<perlref>.
1299
1300=item Not a format reference
1301
1302(F) I'm not sure how you managed to generate a reference to an anonymous
1303format, but this indicates you did, and that it didn't exist.
1304
1305=item Not a GLOB reference
1306
1307(F) Perl was trying to evaluate a reference to a "type glob" (that is,
1308a symbol table entry that looks like C<*foo>), but found a reference to
1309something else instead. You can use the ref() function to find out
1310what kind of ref it really was. See L<perlref>.
1311
1312=item Not a HASH reference
1313
1314(F) Perl was trying to evaluate a reference to a hash value, but
1315found a reference to something else instead. You can use the ref()
1316function to find out what kind of ref it really was. See L<perlref>.
1317
1318=item Not a perl script
1319
1320(F) The setuid emulator requires that scripts have a well-formed #! line
1321even on machines that don't support the #! construct. The line must
1322mention perl.
1323
1324=item Not a SCALAR reference
1325
1326(F) Perl was trying to evaluate a reference to a scalar value, but
1327found a reference to something else instead. You can use the ref()
1328function to find out what kind of ref it really was. See L<perlref>.
1329
1330=item Not a subroutine reference
1331
1332(F) Perl was trying to evaluate a reference to a code value (that is, a
1333subroutine), but found a reference to something else instead. You can
1334use the ref() function to find out what kind of ref it really was.
1335See also L<perlref>.
1336
1337=item Not a subroutine reference in %OVERLOAD
1338
1339(F) An attempt was made to specify an entry in an overloading table that
1340doesn't somehow point to a valid subroutine. See L<perlovl>.
1341
1342=item Not an ARRAY reference
1343
1344(F) Perl was trying to evaluate a reference to an array value, but
1345found a reference to something else instead. You can use the ref()
1346function to find out what kind of ref it really was. See L<perlref>.
1347
1348=item Not enough arguments for %s
1349
1350(F) The function requires more arguments than you specified.
1351
1352=item Not enough format arguments
1353
1354(W) A format specified more picture fields than the next line supplied.
1355See L<perlform>.
1356
1357=item Null filename used
1358
1359(F) You can't require the null filename, especially since on many machines
1360that means the current directory! See L<perlfunc/require>.
1361
1362=item NULL OP IN RUN
1363
1364(P) Some internal routine called run() with a null opcode pointer.
1365
1366=item Null realloc
1367
1368(P) An attempt was made to realloc NULL.
1369
1370=item NULL regexp argument
1371
1372(P) The internal pattern matching routines blew it bigtime.
1373
1374=item NULL regexp parameter
1375
1376(P) The internal pattern matching routines are out of their gourd.
1377
1378=item Odd number of elements in hash list
1379
1380(S) You specified an odd number of elements to a hash list, which is odd,
1381since hash lists come in key/value pairs.
1382
1383=item oops: oopsAV
1384
1385(S) An internal warning that the grammar is screwed up.
1386
1387=item oops: oopsHV
1388
1389(S) An internal warning that the grammar is screwed up.
1390
1391=item Operation `%s' %s: no method found,
1392
1393(F) An attempt was made to use an entry in an overloading table that
1394somehow no longer points to a valid method. See L<perlovl>.
1395
748a9306
LW
1396=item Operator or semicolon missing before %s
1397
1398(S) You used a variable or subroutine call where the parser was
1399expecting an operator. The parser has assumed you really meant
1400to use an operator, but this is highly likely to be incorrect.
1401For example, if you say "*foo *foo" it will be interpreted as
1402if you said "*foo * 'foo'".
1403
a0d0e21e
LW
1404=item Out of memory for yacc stack
1405
1406(F) The yacc parser wanted to grow its stack so it could continue parsing,
1407but realloc() wouldn't give it more memory, virtual or otherwise.
1408
1409=item Out of memory!
1410
1411(X) The malloc() function returned 0, indicating there was insufficient
1412remaining memory (or virtual memory) to satisfy the request.
1413
1414=item page overflow
1415
1416(W) A single call to write() produced more lines than can fit on a page.
1417See L<perlform>.
1418
1419=item panic: ck_grep
1420
1421(P) Failed an internal consistency check trying to compile a grep.
1422
1423=item panic: ck_split
1424
1425(P) Failed an internal consistency check trying to compile a split.
1426
1427=item panic: corrupt saved stack index
1428
1429(P) The savestack was requested to restore more localized values than there
1430are in the savestack.
1431
1432=item panic: die %s
1433
1434(P) We popped the context stack to an eval context, and then discovered
1435it wasn't an eval context.
1436
1437=item panic: do_match
1438
1439(P) The internal pp_match() routine was called with invalid operational data.
1440
1441=item panic: do_split
1442
1443(P) Something terrible went wrong in setting up for the split.
1444
1445=item panic: do_subst
1446
1447(P) The internal pp_subst() routine was called with invalid operational data.
1448
1449=item panic: do_trans
1450
1451(P) The internal do_trans() routine was called with invalid operational data.
1452
1453=item panic: goto
1454
1455(P) We popped the context stack to a context with the specified label,
1456and then discovered it wasn't a context we know how to do a goto in.
1457
1458=item panic: INTERPCASEMOD
1459
1460(P) The lexer got into a bad state at a case modifier.
1461
1462=item panic: INTERPCONCAT
1463
1464(P) The lexer got into a bad state parsing a string with brackets.
1465
1466=item panic: last
1467
1468(P) We popped the context stack to a block context, and then discovered
1469it wasn't a block context.
1470
1471=item panic: leave_scope clearsv
1472
1473(P) A writable lexical variable became readonly somehow within the scope.
1474
1475=item panic: leave_scope inconsistency
1476
1477(P) The savestack probably got out of sync. At least, there was an
1478invalid enum on the top of it.
1479
1480=item panic: malloc
1481
1482(P) Something requested a negative number of bytes of malloc.
1483
1484=item panic: mapstart
1485
1486(P) The compiler is screwed up with respect to the map() function.
1487
1488=item panic: null array
1489
1490(P) One of the internal array routines was passed a null AV pointer.
1491
1492=item panic: pad_alloc
1493
1494(P) The compiler got confused about which scratch pad it was allocating
1495and freeing temporaries and lexicals from.
1496
1497=item panic: pad_free curpad
1498
1499(P) The compiler got confused about which scratch pad it was allocating
1500and freeing temporaries and lexicals from.
1501
1502=item panic: pad_free po
1503
1504(P) An invalid scratch pad offset was detected internally.
1505
1506=item panic: pad_reset curpad
1507
1508(P) The compiler got confused about which scratch pad it was allocating
1509and freeing temporaries and lexicals from.
1510
1511=item panic: pad_sv po
1512
1513(P) An invalid scratch pad offset was detected internally.
1514
1515=item panic: pad_swipe curpad
1516
1517(P) The compiler got confused about which scratch pad it was allocating
1518and freeing temporaries and lexicals from.
1519
1520=item panic: pad_swipe po
1521
1522(P) An invalid scratch pad offset was detected internally.
1523
1524=item panic: pp_iter
1525
1526(P) The foreach iterator got called in a non-loop context frame.
1527
1528=item panic: realloc
1529
1530(P) Something requested a negative number of bytes of realloc.
1531
1532=item panic: restartop
1533
1534(P) Some internal routine requested a goto (or something like it), and
1535didn't supply the destination.
1536
1537=item panic: return
1538
1539(P) We popped the context stack to a subroutine or eval context, and
1540then discovered it wasn't a subroutine or eval context.
1541
1542=item panic: scan_num
1543
1544(P) scan_num() got called on something that wasn't a number.
1545
1546=item panic: sv_insert
1547
1548(P) The sv_insert() routine was told to remove more string than there
1549was string.
1550
1551=item panic: top_env
1552
1553(P) The compiler attempted to do a goto, or something weird like that.
1554
1555=item panic: yylex
1556
1557(P) The lexer got into a bad state while processing a case modifier.
1558
1559=item Parens missing around "%s" list
1560
1561(W) You said something like
1562
1563 my $foo, $bar = @_;
1564
1565when you meant
1566
1567 my ($foo, $bar) = @_;
1568
1569Remember that "my" and "local" bind closer than comma.
1570
1571=item Perl %3.3f required--this is only version %s, stopped
1572
1573(F) The module in question uses features of a version of Perl more recent
1574than the currently running version. How long has it been since you upgraded,
1575anyway? See L<perlfunc/require>.
1576
1577=item Permission denied
1578
1579(F) The setuid emulator in suidperl decided you were up to no good.
1580
748a9306
LW
1581=item pid %d not a child
1582
1583(W) A warning peculiar to VMS. Waitpid() was asked to wait for a process which
1584isn't a subprocess of the current process. While this is fine from VMS'
1585perspective, it's probably not what you intended.
1586
a0d0e21e
LW
1587=item POSIX getpgrp can't take an argument
1588
1589(F) Your C compiler uses POSIX getpgrp(), which takes no argument, unlike
1590the BSD version, which takes a pid.
1591
1592=item Possible memory corruption: %s overflowed 3rd argument
1593
1594(F) An ioctl() or fcntl() returned more than Perl was bargaining for.
1595Perl guesses a reasonable buffer size, but puts a sentinel byte at the
1596end of the buffer just in case. This sentinel byte got clobbered, and
1597Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
1598
1599=item Precedence problem: open %s should be open(%s)
1600
1601(S) The old irregular construct
cb1a09d0 1602
a0d0e21e
LW
1603 open FOO || die;
1604
1605is now misinterpreted as
1606
1607 open(FOO || die);
1608
1609because of the strict regularization of Perl 5's grammar into unary and
1610list operators. (The old open was a little of both.) You must put
1611parens around the filehandle, or use the new "or" operator instead of "||".
1612
1613=item print on closed filehandle %s
1614
1615(W) The filehandle you're printing on got itself closed sometime before now.
1616Check your logic flow.
1617
1618=item printf on closed filehandle %s
1619
1620(W) The filehandle you're writing to got itself closed sometime before now.
1621Check your logic flow.
1622
1623=item Probable precedence problem on %s
1624
1625(W) The compiler found a bare word where it expected a conditional,
1626which often indicates that an || or && was parsed as part of the
1627last argument of the previous construct, for example:
1628
1629 open FOO || die;
1630
4633a7c4
LW
1631=item Prototype mismatch: (%s) vs (%s)
1632
1633(S) The subroutine being defined had a predeclared (forward) declaration
1634with a different function prototype.
1635
a0d0e21e
LW
1636=item Read on closed filehandle <%s>
1637
1638(W) The filehandle you're reading from got itself closed sometime before now.
1639Check your logic flow.
1640
1641=item Reallocation too large: %lx
1642
1643(F) You can't allocate more than 64K on an MSDOS machine.
1644
1645=item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
1646
1647(F) You can't use the B<-D> option unless the code to produce the
1648desired output is compiled into Perl, which entails some overhead,
1649which is why it's currently left out of your copy.
1650
1651=item Recursive inheritance detected
1652
1653(F) More than 100 levels of inheritance were used. Probably indicates
1654an unintended loop in your inheritance hierarchy.
1655
1656=item Reference miscount in sv_replace()
1657
1658(W) The internal sv_replace() function was handed a new SV with a
1659reference count of other than 1.
1660
1661=item regexp memory corruption
1662
1663(P) The regular expression engine got confused by what the regular
1664expression compiler gave it.
1665
1666=item regexp out of space
1667
1668(P) A "can't happen" error, because safemalloc() should have caught it earlier.
1669
1670=item regexp too big
1671
1672(F) The current implementation of regular expression uses shorts as
1673address offsets within a string. Unfortunately this means that if
1674the regular expression compiles to longer than 32767, it'll blow up.
1675Usually when you want a regular expression this big, there is a better
1676way to do it with multiple statements. See L<perlre>.
1677
1678=item Reversed %s= operator
1679
1680(W) You wrote your assignment operator backwards. The = must always
1681comes last, to avoid ambiguity with subsequent unary operators.
1682
1683=item Runaway format
1684
1685(F) Your format contained the ~~ repeat-until-blank sequence, but it
1686produced 200 lines at once, and the 200th line looked exactly like the
1687199th line. Apparently you didn't arrange for the arguments to exhaust
1688themselves, either by using ^ instead of @ (for scalar variables), or by
1689shifting or popping (for array variables). See L<perlform>.
1690
1691=item Scalar value @%s[%s] better written as $%s[%s]
1692
1693(W) You've used an array slice (indicated by @) to select a single value of
1694an array. Generally it's better to ask for a scalar value (indicated by $).
1695The difference is that $foo[&bar] always behaves like a scalar, both when
1696assigning to it and when evaluating its argument, while @foo[&bar] behaves
1697like a list when you assign to it, and provides a list context to its
1698subscript, which can do weird things if you're only expecting one subscript.
1699
748a9306
LW
1700On the other hand, if you were actually hoping to treat the array
1701element as a list, you need to look into how references work, since
1702Perl will not magically convert between scalars and lists for you. See
1703L<perlref>.
1704
a0d0e21e
LW
1705=item Script is not setuid/setgid in suidperl
1706
1707(F) Oddly, the suidperl program was invoked on a script with its setuid
1708or setgid bit set. This doesn't make much sense.
1709
1710=item Search pattern not terminated
1711
1712(F) The lexer couldn't find the final delimiter of a // or m{}
1713construct. Remember that bracketing delimiters count nesting level.
1714
1715=item seek() on unopened file
1716
1717(W) You tried to use the seek() function on a filehandle that was either
1718never opened or has been closed since.
1719
1720=item select not implemented
1721
1722(F) This machine doesn't implement the select() system call.
1723
1724=item sem%s not implemented
1725
1726(F) You don't have System V semaphore IPC on your system.
1727
1728=item semi-panic: attempt to dup freed string
1729
1730(S) The internal newSVsv() routine was called to duplicate a scalar
1731that had previously been marked as free.
1732
1733=item Semicolon seems to be missing
1734
1735(W) A nearby syntax error was probably caused by a missing semicolon,
1736or possibly some other missing operator, such as a comma.
1737
1738=item Send on closed socket
1739
1740(W) The filehandle you're sending to got itself closed sometime before now.
1741Check your logic flow.
1742
1743=item Sequence (?#... not terminated
1744
1745(F) A regular expression comment must be terminated by a closing
1746parenthesis. Embedded parens aren't allowed. See L<perlre>.
1747
1748=item Sequence (?%s...) not implemented
1749
1750(F) A proposed regular expression extension has the character reserved
1751but has not yet been written. See L<perlre>.
1752
1753=item Sequence (?%s...) not recognized
1754
1755(F) You used a regular expression extension that doesn't make sense.
1756See L<perlre>.
1757
a5f75d66
AD
1758=item Server error
1759
1760Also known as "500 Server error". This is a CGI error, not a Perl
1761error. You need to make sure your script is executable, is accessible
1762by the user CGI is running the script under (which is probably not
1763the user account you tested it under), does not rely on any environment
1764variables (like PATH) from the user it isn't running under, and isn't
1765in a location where the CGI server can't find it, basically, more or less.
1766
a0d0e21e
LW
1767=item setegid() not implemented
1768
1769(F) You tried to assign to $), and your operating system doesn't support
1770the setegid() system call (or equivalent), or at least Configure didn't
1771think so.
1772
1773=item seteuid() not implemented
1774
1775(F) You tried to assign to $>, and your operating system doesn't support
1776the seteuid() system call (or equivalent), or at least Configure didn't
1777think so.
1778
1779=item setrgid() not implemented
1780
1781(F) You tried to assign to $(, and your operating system doesn't support
1782the setrgid() system call (or equivalent), or at least Configure didn't
1783think so.
1784
1785=item setruid() not implemented
1786
1787(F) You tried to assign to $<, and your operating system doesn't support
1788the setruid() system call (or equivalent), or at least Configure didn't
1789think so.
1790
1791=item Setuid/gid script is writable by world
1792
1793(F) The setuid emulator won't run a script that is writable by the world,
1794because the world might have written on it already.
1795
1796=item shm%s not implemented
1797
1798(F) You don't have System V shared memory IPC on your system.
1799
1800=item shutdown() on closed fd
1801
1802(W) You tried to do a shutdown on a closed socket. Seems a bit superfluous.
1803
1804=item SIG%s handler "%s" not defined.
1805
1806(W) The signal handler named in %SIG doesn't, in fact, exist. Perhaps you
1807put it into the wrong package?
1808
1809=item sort is now a reserved word
1810
1811(F) An ancient error message that almost nobody ever runs into anymore.
1812But before sort was a keyword, people sometimes used it as a filehandle.
1813
1814=item Sort subroutine didn't return a numeric value
1815
1816(F) A sort comparison routine must return a number. You probably blew
4633a7c4 1817it by not using C<E<lt>=E<gt>> or C<cmp>, or by not using them correctly.
a0d0e21e
LW
1818See L<perlfunc/sort>.
1819
1820=item Sort subroutine didn't return single value
1821
1822(F) A sort comparison subroutine may not return a list value with more
1823or less than one element. See L<perlfunc/sort>.
1824
1825=item Split loop
1826
1827(P) The split was looping infinitely. (Obviously, a split shouldn't iterate
1828more times than there are characters of input, which is what happened.)
1829See L<perlfunc/split>.
1830
1831=item Stat on unopened file <%s>
1832
1833(W) You tried to use the stat() function (or an equivalent file test)
1834on a filehandle that was either never opened or has been closed since.
1835
1836=item Statement unlikely to be reached
1837
1838(W) You did an exec() with some statement after it other than a die().
1839This is almost always an error, because exec() never returns unless
1840there was a failure. You probably wanted to use system() instead,
1841which does return. To suppress this warning, put the exec() in a block
1842by itself.
1843
1844=item Subroutine %s redefined
1845
1846(W) You redefined a subroutine. To suppress this warning, say
1847
1848 {
1849 local $^W = 0;
1850 eval "sub name { ... }";
1851 }
1852
1853=item Substitution loop
1854
1855(P) The substitution was looping infinitely. (Obviously, a
1856substitution shouldn't iterate more times than there are characters of
1857input, which is what happened.) See the discussion of substitution in
1858L<perlop/"Quote and Quotelike Operators">.
1859
1860=item Substitution pattern not terminated
1861
1862(F) The lexer couldn't find the interior delimiter of a s/// or s{}{}
1863construct. Remember that bracketing delimiters count nesting level.
1864
1865=item Substitution replacement not terminated
1866
1867(F) The lexer couldn't find the final delimiter of a s/// or s{}{}
1868construct. Remember that bracketing delimiters count nesting level.
1869
1870=item substr outside of string
1871
1872(W) You tried to reference a substr() that pointed outside of a string.
1873That is, the absolute value of the offset was larger than the length of
1874the string. See L<perlfunc/substr>.
1875
1876=item suidperl is no longer needed since...
1877
1878(F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but a
1879version of the setuid emulator somehow got run anyway.
1880
1881=item syntax error
1882
1883(F) Probably means you had a syntax error. Common reasons include:
1884
1885 A keyword is misspelled.
1886 A semicolon is missing.
1887 A comma is missing.
1888 An opening or closing parenthesis is missing.
1889 An opening or closing brace is missing.
1890 A closing quote is missing.
1891
1892Often there will be another error message associated with the syntax
1893error giving more information. (Sometimes it helps to turn on B<-w>.)
1894The error message itself often tells you where it was in the line when
1895it decided to give up. Sometimes the actual error is several tokens
1896before this, since Perl is good at understanding random input.
1897Occasionally the line number may be misleading, and once in a blue moon
1898the only way to figure out what's triggering the error is to call
1899C<perl -c> repeatedly, chopping away half the program each time to see
1900if the error went away. Sort of the cybernetic version of S<20 questions>.
1901
cb1a09d0
AD
1902=item syntax error at line %d: `%s' unexpected
1903
1904(A) You've accidentally run your script through the Bourne shell
1905instead of Perl. Check the <#!> line, or manually feed your script
1906into Perl yourself.
1907
a0d0e21e
LW
1908=item System V IPC is not implemented on this machine
1909
1910(F) You tried to do something with a function beginning with "sem", "shm"
1911or "msg". See L<perlfunc/semctl>, for example.
1912
1913=item Syswrite on closed filehandle
1914
1915(W) The filehandle you're writing to got itself closed sometime before now.
1916Check your logic flow.
1917
1918=item tell() on unopened file
1919
1920(W) You tried to use the tell() function on a filehandle that was either
1921never opened or has been closed since.
1922
1923=item Test on unopened file <%s>
1924
1925(W) You tried to invoke a file test operator on a filehandle that isn't
1926open. Check your logic. See also L<perlfunc/-X>.
1927
1928=item That use of $[ is unsupported
1929
1930(F) Assignment to $[ is now strictly circumscribed, and interpreted as
1931a compiler directive. You may only say one of
1932
1933 $[ = 0;
1934 $[ = 1;
1935 ...
1936 local $[ = 0;
1937 local $[ = 1;
1938 ...
1939
1940This is to prevent the problem of one module changing the array base
1941out from under another module inadvertently. See L<perlvar/$[>.
1942
1943=item The %s function is unimplemented
1944
1945The function indicated isn't implemented on this architecture, according
1946to the probings of Configure.
1947
1948=item The crypt() function is unimplemented due to excessive paranoia.
1949
1950(F) Configure couldn't find the crypt() function on your machine,
1951probably because your vendor didn't supply it, probably because they
1952think the U.S. Govermnment thinks it's a secret, or at least that they
1953will continue to pretend that it is. And if you quote me on that, I
1954will deny it.
1955
1956=item The stat preceding C<-l _> wasn't an lstat
1957
1958(F) It makes no sense to test the current stat buffer for symbolic linkhood
1959if the last stat that wrote to the stat buffer already went past
1960the symlink to get to the real file. Use an actual filename instead.
1961
1962=item times not implemented
1963
1964(F) Your version of the C library apparently doesn't do times(). I suspect
1965you're not running on Unix.
1966
1967=item Too few args to syscall
1968
1969(F) There has to be at least one argument to syscall() to specify the
1970system call to call, silly dilly.
1971
cb1a09d0
AD
1972=item Too many ('s
1973
1974=item Too many )'s
1975
1976(A) You've accidentally run your script through B<csh> instead
1977of Perl. Check the <#!> line, or manually feed your script
1978into Perl yourself.
1979
a0d0e21e
LW
1980=item Too many args to syscall
1981
1982(F) Perl only supports a maximum of 14 args to syscall().
1983
1984=item Too many arguments for %s
1985
1986(F) The function requires fewer arguments than you specified.
1987
1988=item trailing \ in regexp
1989
1990(F) The regular expression ends with an unbackslashed backslash. Backslash
1991it. See L<perlre>.
1992
1993=item Translation pattern not terminated
1994
1995(F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
1996construct.
1997
1998=item Translation replacement not terminated
1999
2000(F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
2001construct.
2002
2003=item truncate not implemented
2004
2005(F) Your machine doesn't implement a file truncation mechanism that
2006Configure knows about.
2007
2008=item Type of arg %d to %s must be %s (not %s)
2009
2010(F) This function requires the argument in that position to be of a
2011certain type. Arrays must be @NAME or @{EXPR}. Hashes must be
2012%NAME or %{EXPR}. No implicit dereferencing is allowed--use the
2013{EXPR} forms as an explicit dereference. See L<perlref>.
2014
2015=item umask: argument is missing initial 0
2016
2017(W) A umask of 222 is incorrect. It should be 0222, since octal literals
2018always start with 0 in Perl, as in C.
2019
4633a7c4
LW
2020=item Unable to create sub named "%s"
2021
2022(F) You attempted to create or access a subroutine with an illegal name.
2023
a0d0e21e
LW
2024=item Unbalanced context: %d more PUSHes than POPs
2025
2026(W) The exit code detected an internal inconsistency in how many execution
2027contexts were entered and left.
2028
2029=item Unbalanced saves: %d more saves than restores
2030
2031(W) The exit code detected an internal inconsistency in how many
2032values were temporarily localized.
2033
2034=item Unbalanced scopes: %d more ENTERs than LEAVEs
2035
2036(W) The exit code detected an internal inconsistency in how many blocks
2037were entered and left.
2038
2039=item Unbalanced tmps: %d more allocs than frees
2040
2041(W) The exit code detected an internal inconsistency in how many mortal
2042scalars were allocated and freed.
2043
2044=item Undefined format "%s" called
2045
2046(F) The format indicated doesn't seem to exist. Perhaps it's really in
2047another package? See L<perlform>.
2048
2049=item Undefined sort subroutine "%s" called
2050
2051(F) The sort comparison routine specified doesn't seem to exist. Perhaps
2052it's in a different package? See L<perlfunc/sort>.
2053
2054=item Undefined subroutine &%s called
2055
2056(F) The subroutine indicated hasn't been defined, or if it was, it
2057has since been undefined.
2058
2059=item Undefined subroutine called
2060
2061(F) The anonymous subroutine you're trying to call hasn't been defined,
2062or if it was, it has since been undefined.
2063
2064=item Undefined subroutine in sort
2065
2066(F) The sort comparison routine specified is declared but doesn't seem to
2067have been defined yet. See L<perlfunc/sort>.
2068
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LW
2069=item Undefined top format "%s" called
2070
2071(F) The format indicated doesn't seem to exist. Perhaps it's really in
2072another package? See L<perlform>.
2073
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LW
2074=item unexec of %s into %s failed!
2075
2076(F) The unexec() routine failed for some reason. See your local FSF
2077representative, who probably put it there in the first place.
2078
2079=item Unknown BYTEORDER
2080
2081(F) There are no byteswapping functions for a machine with this byte order.
2082
2083=item unmatched () in regexp
2084
2085(F) Unbackslashed parentheses must always be balanced in regular
2086expressions. If you're a vi user, the % key is valuable for finding
2087the matching paren. See L<perlre>.
2088
2089=item Unmatched right bracket
2090
2091(F) The lexer counted more closing curly brackets (braces) than opening
2092ones, so you're probably missing an opening bracket. As a general
2093rule, you'll find the missing one (so to speak) near the place you were
2094last editing.
2095
2096=item unmatched [] in regexp
2097
2098(F) The brackets around a character class must match. If you wish to
2099include a closing bracket in a character class, backslash it or put it first.
2100See L<perlre>.
2101
2102=item Unquoted string "%s" may clash with future reserved word
2103
2104(W) You used a bare word that might someday be claimed as a reserved word.
2105It's best to put such a word in quotes, or capitalize it somehow, or insert
2106an underbar into it. You might also declare it as a subroutine.
2107
2108=item Unrecognized character \%03o ignored
2109
2110(S) A garbage character was found in the input, and ignored, in case it's
2111a weird control character on an EBCDIC machine, or some such.
2112
2113=item Unrecognized signal name "%s"
2114
2115(F) You specified a signal name to the kill() function that was not recognized.
2116Say C<kill -l> in your shell to see the valid signal names on your system.
2117
2118=item Unrecognized switch: -%s
2119
2120(F) You specified an illegal option to Perl. Don't do that.
2121(If you think you didn't do that, check the #! line to see if it's
2122supplying the bad switch on your behalf.)
2123
2124=item Unsuccessful %s on filename containing newline
2125
2126(W) A file operation was attempted on a filename, and that operation
2127failed, PROBABLY because the filename contained a newline, PROBABLY
2128because you forgot to chop() or chomp() it off. See L<perlfunc/chop>.
2129
2130=item Unsupported directory function "%s" called
2131
2132(F) Your machine doesn't support opendir() and readdir().
2133
2134=item Unsupported function %s
2135
2136(F) This machines doesn't implement the indicated function, apparently.
2137At least, Configure doesn't think so.
2138
2139=item Unsupported socket function "%s" called
2140
2141(F) Your machine doesn't support the Berkeley socket mechanism, or at
2142least that's what Configure thought.
2143
2144=item Unterminated <> operator
2145
2146(F) The lexer saw a left angle bracket in a place where it was expecting
2147a term, so it's looking for the corresponding right angle bracket, and not
2148finding it. Chances are you left some needed parentheses out earlier in
2149the line, and you really meant a "less than".
2150
2151=item Use of $# is deprecated
2152
2153(D) This was an ill-advised attempt to emulate a poorly defined awk feature.
2154Use an explicit printf() or sprintf() instead.
2155
2156=item Use of $* is deprecated
2157
2158(D) This variable magically turned on multiline pattern matching, both for
2159you and for any luckless subroutine that you happen to call. You should
2160use the new C<//m> and C<//s> modifiers now to do that without the dangerous
2161action-at-a-distance effects of C<$*>.
2162
748a9306
LW
2163=item Use of %s in printf format not supported
2164
2165(F) You attempted to use a feature of printf that is accessible only
2166from C. This usually means there's a better way to do it in Perl.
2167
a0d0e21e
LW
2168=item Use of %s is deprecated
2169
2170(D) The construct indicated is no longer recommended for use, generally
2171because there's a better way to do it, and also because the old way has
2172bad side effects.
2173
4633a7c4
LW
2174=item Use of bare << to mean <<"" is deprecated
2175
2176(D) You are now encouraged to use the explicitly quoted form if you
2177wish to use a blank line as the terminator of the here-document.
2178
a0d0e21e
LW
2179=item Use of implicit split to @_ is deprecated
2180
2181(D) It makes a lot of work for the compiler when you clobber a
2182subroutine's argument list, so it's better if you assign the results of
2183a split() explicitly to an array (or list).
2184
2185=item Use of uninitialized value
2186
2187(W) An undefined value was used as if it were already defined. It was
2188interpreted as a "" or a 0, but maybe it was a mistake. To suppress this
2189warning assign an initial value to your variables.
2190
2191=item Useless use of %s in void context
2192
2193(W) You did something without a side effect in a context that does nothing
2194with the return value, such as a statement that doesn't return a value
2195from a block, or the left side of a scalar comma operator. Very often
2196this points not to stupidity on your part, but a failure of Perl to parse
2197your program the way you thought it would. For example, you'd get this
2198if you mixed up your C precedence with Python precedence and said
2199
2200 $one, $two = 1, 2;
2201
2202when you meant to say
2203
2204 ($one, $two) = (1, 2);
2205
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LW
2206Another common error is to use ordinary parentheses to construct a list
2207reference when you should be using square or curly brackets, for
2208example, if you say
2209
2210 $array = (1,2);
2211
2212when you should have said
2213
2214 $array = [1,2];
2215
2216The square brackets explicitly turn a list value into a scalar value,
2217while parentheses do not. So when a parenthesized list is evaluated in
2218a scalar context, the comma is treated like C's comma operator, which
2219throws away the left argument, which is not what you want. See
2220L<perlref> for more on this.
2221
4633a7c4
LW
2222=item Variable "%s" is not exported
2223
2224(F) While "use strict" in effect, you referred to a global variable
2225that you apparently thought was imported from another module, because
2226something else of the same name (usually a subroutine) is exported
2227by that module. It usually means you put the wrong funny character
2228on the front of your variable.
2229
cb1a09d0
AD
2230=item Variable syntax.
2231
2232(A) You've accidentally run your script through B<csh> instead
2233of Perl. Check the <#!> line, or manually feed your script
2234into Perl yourself.
2235
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LW
2236=item Warning: unable to close filehandle %s properly.
2237
2238(S) The implicit close() done by an open() got an error indication on the
2239close(0. This usually indicates your filesystem ran out of disk space.
2240
2241=item Warning: Use of "%s" without parens is ambiguous
2242
2243(S) You wrote a unary operator followed by something that looks like a
2244binary operator that could also have been interpreted as a term or
2245unary operator. For instance, if you know that the rand function
2246has a default argument of 1.0, and you write
2247
2248 rand + 5;
2249
2250you may THINK you wrote the same thing as
2251
2252 rand() + 5;
2253
2254but in actual fact, you got
2255
2256 rand(+5);
2257
2258So put in parens to say what you really mean.
2259
2260=item Write on closed filehandle
2261
2262(W) The filehandle you're writing to got itself closed sometime before now.
2263Check your logic flow.
2264
2265=item X outside of string
2266
2267(F) You had a pack template that specified a relative position before
2268the beginning of the string being unpacked. See L<perlfunc/pack>.
2269
2270=item x outside of string
2271
2272(F) You had a pack template that specified a relative position after
2273the end of the string being unpacked. See L<perlfunc/pack>.
2274
2275=item Xsub "%s" called in sort
2276
2277(F) The use of an external subroutine as a sort comparison is not yet supported.
2278
2279=item Xsub called in sort
2280
2281(F) The use of an external subroutine as a sort comparison is not yet supported.
2282
2283=item You can't use C<-l> on a filehandle
2284
2285(F) A filehandle represents an opened file, and when you opened the file it
2286already went past any symlink you are presumably trying to look for.
2287Use a filename instead.
2288
2289=item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
2290
2291(F) And you probably never will, since you probably don't have the
2292sources to your kernel, and your vendor probably doesn't give a rip
2293about what you want. Your best bet is to use the wrapsuid script in
2294the eg directory to put a setuid C wrapper around your script.
2295
2296=item You need to quote "%s"
2297
2298(W) You assigned a bareword as a signal handler name. Unfortunately, you
2299already have a subroutine of that name declared, which means that Perl 5
2300will try to call the subroutine when the assignment is executed, which is
2301probably not what you want. (If it IS what you want, put an & in front.)
2302
2303=item [gs]etsockopt() on closed fd
2304
2305(W) You tried to get or set a socket option on a closed socket.
2306Did you forget to check the return value of your socket() call?
2307See L<perlfunc/getsockopt>.
2308
2309=item \1 better written as $1
2310
2311(W) Outside of patterns, backreferences live on as variables. The use
2312of backslashes is grandfathered on the righthand side of a
2313substitution, but stylistically it's better to use the variable form
2314because other Perl programmers will expect it, and it works better
2315if there are more than 9 backreferences.
2316
748a9306
LW
2317=item '|' and '<' may not both be specified on command line
2318
2319(F) An error peculiar to VMS. Perl does its own command line redirection, and
2320found that STDIN was a pipe, and that you also tried to redirect STDIN using
2321'<'. Only one STDIN stream to a customer, please.
2322
2323=item '|' and '>' may not both be specified on command line
2324
2325(F) An error peculiar to VMS. Perl does its own command line redirection, and
2326thinks you tried to redirect stdout both to a file and into a pipe to another
2327command. You need to choose one or the other, though nothing's stopping you
2328from piping into a program or Perl script which 'splits' output into two
2329streams, such as
2330
2331 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
2332 while (<STDIN>) {
2333 print;
2334 print OUT;
2335 }
2336 close OUT;
2337
a0d0e21e
LW
2338=back
2339