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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,
2ba9eb46 25just as in a printf format. Note that some messages start with a %s!
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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
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36=item "my" variable %s masks earlier declaration in same scope
37
38(S) A lexical variable has been redeclared in the same scope, effectively
39eliminating all access to the previous instance. This is almost always
40a typographical error. Note that the earlier variable will still exist
41until the end of the scope or until all closure referents to it are
42destroyed.
43
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44=item "no" not allowed in expression
45
46(F) The "no" keyword is recognized and executed at compile time, and returns
47no useful value. See L<perlmod>.
48
49=item "use" not allowed in expression
50
51(F) The "use" keyword is recognized and executed at compile time, and returns
52no useful value. See L<perlmod>.
53
54=item % may only be used in unpack
55
56(F) You can't pack a string by supplying a checksum, since the
57checksumming process loses information, and you can't go the other
58way. See L<perlfunc/unpack>.
59
60=item %s (...) interpreted as function
61
62(W) You've run afoul of the rule that says that any list operator followed
63by parentheses turns into a function, with all the list operators arguments
64found inside the parens. See L<perlop/Terms and List Operators (Leftward)>.
65
66=item %s argument is not a HASH element
67
68(F) The argument to delete() or exists() must be a hash element, such as
69
70 $foo{$bar}
71 $ref->[12]->{"susie"}
72
73=item %s did not return a true value
74
75(F) A required (or used) file must return a true value to indicate that
76it compiled correctly and ran its initialization code correctly. It's
77traditional to end such a file with a "1;", though any true value would
78do. See L<perlfunc/require>.
79
80=item %s found where operator expected
81
82(S) The Perl lexer knows whether to expect a term or an operator. If it
83sees what it knows to be a term when it was expecting to see an operator,
84it gives you this warning. Usually it indicates that an operator or
85delimiter was omitted, such as a semicolon.
86
87=item %s had compilation errors.
88
89(F) The final summary message when a C<perl -c> fails.
90
91=item %s has too many errors.
92
93(F) The parser has given up trying to parse the program after 10 errors.
94Further error messages would likely be uninformative.
95
96=item %s matches null string many times
97
98(W) The pattern you've specified would be an infinite loop if the
99regular expression engine didn't specifically check for that. See L<perlre>.
100
101=item %s never introduced
102
103(S) The symbol in question was declared but somehow went out of scope
104before it could possibly have been used.
105
106=item %s syntax OK
107
108(F) The final summary message when a C<perl -c> succeeds.
109
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110=item %s: Command not found.
111
112(A) You've accidentally run your script through B<csh> instead
113of Perl. Check the <#!> line, or manually feed your script
114into Perl yourself.
115
116=item %s: Expression syntax.
117
118(A) You've accidentally run your script through B<csh> instead
119of Perl. Check the <#!> line, or manually feed your script
120into Perl yourself.
121
122=item %s: Undefined variable.
123
124(A) You've accidentally run your script through B<csh> instead
125of Perl. Check the <#!> line, or manually feed your script
126into Perl yourself.
127
128=item %s: not found
129
130(A) You've accidentally run your script through the Bourne shell
131instead of Perl. Check the <#!> line, or manually feed your script
132into Perl yourself.
133
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134=item B<-P> not allowed for setuid/setgid script
135
136(F) The script would have to be opened by the C preprocessor by name,
137which provides a race condition that breaks security.
138
139=item C<-T> and C<-B> not implemented on filehandles
140
141(F) Perl can't peek at the stdio buffer of filehandles when it doesn't
142know about your kind of stdio. You'll have to use a filename instead.
143
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144=item 500 Server error
145
146See Server error.
147
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148=item ?+* follows nothing in regexp
149
150(F) You started a regular expression with a quantifier. Backslash it
151if you meant it literally. See L<perlre>.
152
153=item @ outside of string
154
2ba9eb46 155(F) You had a pack template that specified an absolute position outside
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156the string being unpacked. See L<perlfunc/pack>.
157
158=item accept() on closed fd
159
160(W) You tried to do an accept on a closed socket. Did you forget to check
161the return value of your socket() call? See L<perlfunc/accept>.
162
163=item Allocation too large: %lx
164
165(F) You can't allocate more than 64K on an MSDOS machine.
166
167=item Arg too short for msgsnd
168
169(F) msgsnd() requires a string at least as long as sizeof(long).
170
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171=item Ambiguous use of %s resolved as %s
172
173(W)(S) You said something that may not be interpreted the way
174you thought. Normally it's pretty easy to disambiguate it by supplying
175a missing quote, operator, paren pair or declaration.
176
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177=item Args must match #! line
178
179(F) The setuid emulator requires that the arguments Perl was invoked
180with match the arguments specified on the #! line.
181
182=item Argument "%s" isn't numeric
183
184(W) The indicated string was fed as an argument to an operator that
185expected a numeric value instead. If you're fortunate the message
186will identify which operator was so unfortunate.
187
188=item Array @%s missing the @ in argument %d of %s()
189
190(D) Really old Perl let you omit the @ on array names in some spots. This
191is now heavily deprecated.
192
193=item assertion botched: %s
194
195(P) The malloc package that comes with Perl had an internal failure.
196
197=item Assertion failed: file "%s"
198
199(P) A general assertion failed. The file in question must be examined.
200
201=item Assignment to both a list and a scalar
202
203(F) If you assign to a conditional operator, the 2nd and 3rd arguments
204must either both be scalars or both be lists. Otherwise Perl won't
205know which context to supply to the right side.
206
207=item Attempt to free non-arena SV: 0x%lx
208
209(P) All SV objects are supposed to be allocated from arenas that will
210be garbage collected on exit. An SV was discovered to be outside any
211of those arenas.
212
213=item Attempt to free temp prematurely
214
215(W) Mortalized values are supposed to be freed by the free_tmps()
216routine. This indicates that something else is freeing the SV before
217the free_tmps() routine gets a chance, which means that the free_tmps()
218routine will be freeing an unreferenced scalar when it does try to free
219it.
220
221=item Attempt to free unreferenced glob pointers
222
223(P) The reference counts got screwed up on symbol aliases.
224
225=item Attempt to free unreferenced scalar
226
227(W) Perl went to decrement the reference count of a scalar to see if it
228would go to 0, and discovered that it had already gone to 0 earlier,
229and should have been freed, and in fact, probably was freed. This
230could indicate that SvREFCNT_dec() was called too many times, or that
231SvREFCNT_inc() was called too few times, or that the SV was mortalized
232when it shouldn't have been, or that memory has been corrupted.
233
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234=item Attempt to use reference as lvalue in substr
235
236(W) You supplied a reference as the first argument to substr() used
237as an lvalue, which is pretty strange. Perhaps you forgot to
238dereference it first. See L<perlfunc/substr>.
239
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240=item Bad arg length for %s, is %d, should be %d
241
242(F) You passed a buffer of the wrong size to one of msgctl(), semctl() or
2ba9eb46 243shmctl(). In C parlance, the correct sizes are, respectively,
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244S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)> and
245S<sizeof(struct shmid_ds *)>.
246
247=item Bad associative array
248
249(P) One of the internal hash routines was passed a null HV pointer.
250
251=item Bad filehandle: %s
252
253(F) A symbol was passed to something wanting a filehandle, but the symbol
254has no filehandle associated with it. Perhaps you didn't do an open(), or
255did it in another package.
256
257=item Bad free() ignored
258
259(S) An internal routine called free() on something that had never been
260malloc()ed in the first place.
261
262=item Bad name after %s::
263
264(F) You started to name a symbol by using a package prefix, and then didn't
265finish the symbol. In particular, you can't interpolate outside of quotes,
266so
267
268 $var = 'myvar';
269 $sym = mypack::$var;
270
271is not the same as
272
273 $var = 'myvar';
274 $sym = "mypack::$var";
275
276=item Bad symbol for array
277
278(P) An internal request asked to add an array entry to something that
279wasn't a symbol table entry.
280
281=item Bad symbol for filehandle
282
283(P) An internal request asked to add a filehandle entry to something that
284wasn't a symbol table entry.
285
286=item Bad symbol for hash
287
288(P) An internal request asked to add a hash entry to something that
289wasn't a symbol table entry.
290
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291=item Badly places ()'s
292
293(A) You've accidentally run your script through B<csh> instead
294of Perl. Check the <#!> line, or manually feed your script
295into Perl yourself.
296
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297=item BEGIN failed--compilation aborted
298
299(F) An untrapped exception was raised while executing a BEGIN subroutine.
300Compilation stops immediately and the interpreter is exited.
301
302=item bind() on closed fd
303
304(W) You tried to do a bind on a closed socket. Did you forget to check
305the return value of your socket() call? See L<perlfunc/bind>.
306
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307=item Bizarre copy of %s in %s
308
309(P) Perl detected an attempt to copy an internal value that is not copiable.
310
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311=item Callback called exit
312
313(F) A subroutine invoked from an external package via perl_call_sv()
314exited by calling exit.
315
316=item Can't "last" outside a block
317
318(F) A "last" statement was executed to break out of the current block,
319except that there's this itty bitty problem called there isn't a
320current block. Note that an "if" or "else" block doesn't count as a
321"loopish" block. You can usually double the curlies to get the same
322effect though, since the inner curlies will be considered a block
323that loops once. See L<perlfunc/last>.
324
325=item Can't "next" outside a block
326
327(F) A "next" statement was executed to reiterate the current block, but
328there isn't a current block. Note that an "if" or "else" block doesn't
329count as a "loopish" block. You can usually double the curlies to get
330the same effect though, since the inner curlies will be considered a block
331that loops once. See L<perlfunc/last>.
332
333=item Can't "redo" outside a block
334
335(F) A "redo" statement was executed to restart the current block, but
336there isn't a current block. Note that an "if" or "else" block doesn't
337count as a "loopish" block. You can usually double the curlies to get
338the same effect though, since the inner curlies will be considered a block
339that loops once. See L<perlfunc/last>.
340
341=item Can't bless non-reference value
342
343(F) Only hard references may be blessed. This is how Perl "enforces"
344encapsulation of objects. See L<perlobj>.
345
346=item Can't break at that line
347
348(S) A warning intended for while running within the debugger, indicating
349the line number specified wasn't the location of a statement that could
350be stopped at.
351
352=item Can't call method "%s" in empty package "%s"
353
354(F) You called a method correctly, and it correctly indicated a package
355functioning as a class, but that package doesn't have ANYTHING defined
356in it, let alone methods. See L<perlobj>.
357
358=item Can't call method "%s" on unblessed reference
359
360(F) A method call must know what package it's supposed to run in. It
361ordinarily finds this out from the object reference you supply, but
362you didn't supply an object reference in this case. A reference isn't
363an object reference until it has been blessed. See L<perlobj>.
364
365=item Can't call method "%s" without a package or object reference
366
367(F) You used the syntax of a method call, but the slot filled by the
368object reference or package name contains an expression that returns
369neither an object reference nor a package name. (Perhaps it's null?)
370Something like this will reproduce the error:
371
372 $BADREF = undef;
373 process $BADREF 1,2,3;
374 $BADREF->process(1,2,3);
375
376=item Can't chdir to %s
377
378(F) You called C<perl -x/foo/bar>, but C</foo/bar> is not a directory
379that you can chdir to, possibly because it doesn't exist.
380
381=item Can't coerce %s to integer in %s
382
383(F) Certain types of SVs, in particular real symbol table entries
384(type GLOB), can't be forced to stop being what they are. So you can't
385say things like:
386
387 *foo += 1;
388
389You CAN say
390
391 $foo = *foo;
392 $foo += 1;
393
394but then $foo no longer contains a glob.
395
396=item Can't coerce %s to number in %s
397
398(F) Certain types of SVs, in particular real symbol table entries
399(type GLOB), can't be forced to stop being what they are.
400
401=item Can't coerce %s to string in %s
402
403(F) Certain types of SVs, in particular real symbol table entries
404(type GLOB), can't be forced to stop being what they are.
405
406=item Can't create pipe mailbox
407
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408(P) An error peculiar to VMS. The process is suffering from exhausted quotas
409or other plumbing problems.
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410
411=item Can't declare %s in my
412
413(F) Only scalar, array and hash variables may be declared as lexical variables.
414They must have ordinary identifiers as names.
415
416=item Can't do inplace edit on %s: %s
417
418(S) The creation of the new file failed for the indicated reason.
419
420=item Can't do inplace edit without backup
421
422(F) You're on a system such as MSDOS that gets confused if you try reading
423from a deleted (but still opened) file. You have to say B<-i>C<.bak>, or some
424such.
425
426=item Can't do inplace edit: %s > 14 characters
427
428(S) There isn't enough room in the filename to make a backup name for the file.
429
430=item Can't do inplace edit: %s is not a regular file
431
432(S) You tried to use the B<-i> switch on a special file, such as a file in
433/dev, or a FIFO. The file was ignored.
434
435=item Can't do setegid!
436
437(P) The setegid() call failed for some reason in the setuid emulator
438of suidperl.
439
440=item Can't do seteuid!
441
442(P) The setuid emulator of suidperl failed for some reason.
443
444=item Can't do setuid
445
446(F) This typically means that ordinary perl tried to exec suidperl to
447do setuid emulation, but couldn't exec it. It looks for a name of the
448form sperl5.000 in the same directory that the perl executable resides
449under the name perl5.000, typically /usr/local/bin on Unix machines.
450If the file is there, check the execute permissions. If it isn't, ask
451your sysadmin why he and/or she removed it.
452
453=item Can't do waitpid with flags
454
455(F) This machine doesn't have either waitpid() or wait4(), so only waitpid()
456without flags is emulated.
457
458=item Can't do {n,m} with n > m
459
460(F) Minima must be less than or equal to maxima. If you really want
461your regexp to match something 0 times, just put {0}. See L<perlre>.
462
463=item Can't emulate -%s on #! line
464
465(F) The #! line specifies a switch that doesn't make sense at this point.
466For example, it'd be kind of silly to put a B<-x> on the #! line.
467
468=item Can't exec "%s": %s
469
470(W) An system(), exec() or piped open call could not execute the named
471program for the indicated reason. Typical reasons include: the permissions
472were wrong on the file, the file wasn't found in C<$ENV{PATH}>, the
473executable in question was compiled for another architecture, or the
474#! line in a script points to an interpreter that can't be run for
475similar reasons. (Or maybe your system doesn't support #! at all.)
476
477=item Can't exec %s
478
479(F) Perl was trying to execute the indicated program for you because that's
480what the #! line said. If that's not what you wanted, you may need to
481mention "perl" on the #! line somewhere.
482
483=item Can't execute %s
484
485(F) You used the B<-S> switch, but the script to execute could not be found
486in the PATH, or at least not with the correct permissions.
487
488=item Can't find label %s
489
490(F) You said to goto a label that isn't mentioned anywhere that it's possible
491for us to go to. See L<perlfunc/goto>.
492
493=item Can't find string terminator %s anywhere before EOF
494
495(F) Perl strings can stretch over multiple lines. This message means that
496the closing delimiter was omitted. Since bracketed quotes count nesting
497levels, the following is missing its final parenthesis:
498
499 print q(The character '(' starts a side comment.)
500
501=item Can't fork
502
503(F) A fatal error occurred while trying to fork while opening a pipeline.
504
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505=item Can't get filespec - stale stat buffer?
506
507(S) A warning peculiar to VMS. This arises because of the difference between
508access checks under VMS and under the Unix model Perl assumes. Under VMS,
509access checks are done by filename, rather than by bits in the stat buffer, so
510that ACLs and other protections can be taken into account. Unfortunately, Perl
511assumes that the stat buffer contains all the necessary information, and passes
512it, instead of the filespec, to the access checking routine. It will try to
513retrieve the filespec using the device name and FID present in the stat buffer,
514but this works only if you haven't made a subsequent call to the CRTL stat()
515routine, since the device name is overwritten with each call. If this warning
516appears, the name lookup failed, and the access checking routine gave up and
517returned FALSE, just to be conservative. (Note: The access checking routine
518knows about the Perl C<stat> operator and file tests, so you shouldn't ever
519see this warning in response to a Perl command; it arises only if some internal
520code takes stat buffers lightly.)
521
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522=item Can't get pipe mailbox device name
523
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524(P) An error peculiar to VMS. After creating a mailbox to act as a pipe, Perl
525can't retrieve its name for later use.
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526
527=item Can't get SYSGEN parameter value for MAXBUF
528
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529(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
530mailbox buffers to be, and didn't get an answer.
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531
532=item Can't goto subroutine outside a subroutine
533
534(F) The deeply magical "goto subroutine" call can only replace one subroutine
535call for another. It can't manufacture one out of whole cloth. In general
536you should only be calling it out of an AUTOLOAD routine anyway. See
537L<perlfunc/goto>.
538
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539=item Can't localize a reference
540
541(F) You said something like C<local $$ref>, which is not allowed because
542the compiler can't determine whether $ref will end up pointing to anything
543with a symbol table entry, and a symbol table entry is necessary to
544do a local.
545
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546=item Can't localize lexical variable %s
547
2ba9eb46 548(F) You used local on a variable name that was previously declared as a
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549lexical variable using "my". This is not allowed. If you want to
550localize a package variable of the same name, qualify it with the
551package name.
552
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553=item Can't locate %s in @INC
554
555(F) You said to do (or require, or use) a file that couldn't be found
556in any of the libraries mentioned in @INC. Perhaps you need to set
557the PERL5LIB environment variable to say where the extra library is,
558or maybe the script needs to add the library name to @INC. Or maybe
559you just misspelled the name of the file. See L<perlfunc/require>.
560
561=item Can't locate object method "%s" via package "%s"
562
563(F) You called a method correctly, and it correctly indicated a package
564functioning as a class, but that package doesn't define that particular
2ba9eb46 565method, nor does any of its base classes. See L<perlobj>.
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566
567=item Can't locate package %s for @%s::ISA
568
569(W) The @ISA array contained the name of another package that doesn't seem
570to exist.
571
572=item Can't mktemp()
573
574(F) The mktemp() routine failed for some reason while trying to process
575a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
576
577=item Can't modify %s in %s
578
579(F) You aren't allowed to assign to the item indicated, or otherwise try to
580change it, such as with an autoincrement.
581
582=item Can't modify non-existent substring
583
584(P) The internal routine that does assignment to a substr() was handed
585a NULL.
586
587=item Can't msgrcv to readonly var
588
589(F) The target of a msgrcv must be modifiable in order to be used as a receive
590buffer.
591
592=item Can't open %s: %s
593
594(S) An inplace edit couldn't open the original file for the indicated reason.
595Usually this is because you don't have read permission for the file.
596
597=item Can't open bidirectional pipe
598
599(W) You tried to say C<open(CMD, "|cmd|")>, which is not supported. You can
600try any of several modules in the Perl library to do this, such as
601"open2.pl". Alternately, direct the pipe's output to a file using ">",
602and then read it in under a different file handle.
603
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604=item Can't open error file %s as stderr
605
606(F) An error peculiar to VMS. Perl does its own command line redirection, and
607couldn't open the file specified after '2>' or '2>>' on the command line for
608writing.
609
610=item Can't open input file %s as stdin
611
612(F) An error peculiar to VMS. Perl does its own command line redirection, and
613couldn't open the file specified after '<' on the command line for reading.
614
615=item Can't open output file %s as stdout
616
617(F) An error peculiar to VMS. Perl does its own command line redirection, and
618couldn't open the file specified after '>' or '>>' on the command line for
619writing.
620
621=item Can't open output pipe (name: %s)
622
623(P) An error peculiar to VMS. Perl does its own command line redirection, and
624couldn't open the pipe into which to send data destined for stdout.
625
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626=item Can't open perl script "%s": %s
627
628(F) The script you specified can't be opened for the indicated reason.
629
630=item Can't rename %s to %s: %s, skipping file
631
632(S) The rename done by the B<-i> switch failed for some reason, probably because
633you don't have write permission to the directory.
634
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635=item Can't reopen input pipe (name: %s) in binary mode
636
637(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried to
638reopen it to accept binary data. Alas, it failed.
639
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640=item Can't reswap uid and euid
641
642(P) The setreuid() call failed for some reason in the setuid emulator
643of suidperl.
644
645=item Can't return outside a subroutine
646
647(F) The return statement was executed in mainline code, that is, where
648there was no subroutine call to return out of. See L<perlsub>.
649
650=item Can't stat script "%s"
651
652(P) For some reason you can't fstat() the script even though you have
653it open already. Bizarre.
654
655=item Can't swap uid and euid
656
657(P) The setreuid() call failed for some reason in the setuid emulator
658of suidperl.
659
660=item Can't take log of %g
661
662(F) Logarithms are only defined on positive real numbers.
663
664=item Can't take sqrt of %g
665
666(F) For ordinary real numbers, you can't take the square root of a
667negative number. There's a Complex package available for Perl, though,
668if you really want to do that.
669
670=item Can't undef active subroutine
671
672(F) You can't undefine a routine that's currently running. You can,
673however, redefine it while it's running, and you can even undef the
674redefined subroutine while the old routine is running. Go figure.
675
676=item Can't unshift
677
678(F) You tried to unshift an "unreal" array that can't be unshifted, such
679as the main Perl stack.
680
2ba9eb46
PP
681=item Can't untie: %d inner references still exist
682
683(F) With "use strict untie" in effect, a copy of the object returned
684from C<tie> (or C<tied>) was still valid when C<untie> was called.
685
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LW
686=item Can't upgrade that kind of scalar
687
688(P) The internal sv_upgrade routine adds "members" to an SV, making
689it into a more specialized kind of SV. The top several SV types are
690so specialized, however, that they cannot be interconverted. This
691message indicates that such a conversion was attempted.
692
693=item Can't upgrade to undef
694
695(P) The undefined SV is the bottom of the totem pole, in the scheme
696of upgradability. Upgrading to undef indicates an error in the
697code calling sv_upgrade.
698
c07a80fd
PP
699=item Can't use "my %s" in sort comparison
700
701(F) The global variables $a and $b are reserved for sort comparisons.
702You mentioned $a or $b in the same line as the <=> or cmp operator,
703and the variable had earlier been declared as a lexical variable.
704Either qualify the sort variable with the package name, or rename the
705lexical variable.
706
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LW
707=item Can't use %s for loop variable
708
709(F) Only a simple scalar variable may be used as a loop variable on a foreach.
710
711=item Can't use %s ref as %s ref
712
713(F) You've mixed up your reference types. You have to dereference a
714reference of the type needed. You can use the ref() function to
715test the type of the reference, if need be.
716
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LW
717=item Can't use \1 to mean $1 in expression
718
719(W) In an ordinary expression, backslash is a unary operator that creates
720a reference to its argument. The use of backslash to indicate a backreference
721to a matched substring is only valid as part of a regular expression pattern.
722Trying to do this in ordinary Perl code produces a value that prints
723out looking like SCALAR(0xdecaf). Use the $1 form instead.
724
725=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e
LW
726
727(F) Only hard references are allowed by "strict refs". Symbolic references
728are disallowed. See L<perlref>.
729
730=item Can't use an undefined value as %s reference
731
732(F) A value used as either a hard reference or a symbolic reference must
733be a defined value. This helps to de-lurk some insidious errors.
734
a0d0e21e
LW
735=item Can't use global %s in "my"
736
737(F) You tried to declare a magical variable as a lexical variable. This is
738not allowed, because the magic can only be tied to one location (namely
739the global variable) and it would be incredibly confusing to have
740variables in your program that looked like magical variables but
741weren't.
742
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LW
743=item Can't use subscript on %s
744
745(F) The compiler tried to interpret a bracketed expression as a
746subscript. But to the left of the brackets was an expression that
747didn't look like an array reference, or anything else subscriptable.
748
a0d0e21e
LW
749=item Can't write to temp file for B<-e>: %s
750
751(F) The write routine failed for some reason while trying to process
752a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
753
754=item Can't x= to readonly value
755
756(F) You tried to repeat a constant value (often the undefined value) with
757an assignment operator, which implies modifying the value itself.
758Perhaps you need to copy the value to a temporary, and repeat that.
759
760=item Cannot open temporary file
761
762(F) The create routine failed for some reaon while trying to process
763a B<-e> switch. Maybe your /tmp partition is full, or clobbered.
764
765=item chmod: mode argument is missing initial 0
766
767(W) A novice will sometimes say
768
769 chmod 777, $filename
770
771not realizing that 777 will be interpreted as a decimal number, equivalent
772to 01411. Octal constants are introduced with a leading 0 in Perl, as in C.
773
774=item Close on unopened file <%s>
775
776(W) You tried to close a filehandle that was never opened.
777
778=item connect() on closed fd
779
780(W) You tried to do a connect on a closed socket. Did you forget to check
781the return value of your socket() call? See L<perlfunc/connect>.
782
783=item Corrupt malloc ptr 0x%lx at 0x%lx
784
785(P) The malloc package that comes with Perl had an internal failure.
786
787=item corrupted regexp pointers
788
789(P) The regular expression engine got confused by what the regular
790expression compiler gave it.
791
792=item corrupted regexp program
793
794(P) The regular expression engine got passed a regexp program without
795a valid magic number.
796
797=item Deep recursion on subroutine "%s"
798
799(W) This subroutine has called itself (directly or indirectly) 100
800times than it has returned. This probably indicates an infinite
801recursion, unless you're writing strange benchmark programs, in which
802case it indicates something else.
803
4633a7c4
LW
804=item Did you mean &%s instead?
805
806(W) You probably referred to an imported subroutine &FOO as $FOO or some such.
807
748a9306 808=item Did you mean $ or @ instead of %?
a0d0e21e 809
748a9306
LW
810(W) You probably said %hash{$key} when you meant $hash{$key} or @hash{@keys}.
811On the other hand, maybe you just meant %hash and got carried away.
812
813=item Do you need to predeclare %s?
814
815(S) This is an educated guess made in conjunction with the message "%s
816found where operator expected". It often means a subroutine or module
817name is being referenced that hasn't been declared yet. This may be
818because of ordering problems in your file, or because of a missing
819"sub", "package", "require", or "use" statement. If you're
820referencing something that isn't defined yet, you don't actually have
821to define the subroutine or package before the current location. You
822can use an empty "sub foo;" or "package FOO;" to enter a "forward"
823declaration.
a0d0e21e
LW
824
825=item Don't know how to handle magic of type '%s'
826
827(P) The internal handling of magical variables has been cursed.
828
829=item do_study: out of memory
830
831(P) This should have been caught by safemalloc() instead.
832
833=item Duplicate free() ignored
834
835(S) An internal routine called free() on something that had already
836been freed.
837
4633a7c4
LW
838=item elseif should be elsif
839
840(S) There is no keyword "elseif" in Perl because Larry thinks it's
841ugly. Your code will be interpreted as an attempt to call a method
842named "elseif" for the class returned by the following block. This is
843unlikely to be what you want.
844
a0d0e21e
LW
845=item END failed--cleanup aborted
846
847(F) An untrapped exception was raised while executing an END subroutine.
848The interpreter is immediately exited.
849
748a9306
LW
850=item Error converting file specification %s
851
852(F) An error peculiar to VMS. Since Perl may have to deal with file
853specifications in either VMS or Unix syntax, it converts them to a
854single form when it must operate on them directly. Either you've
855passed an invalid file specification to Perl, or you've found a
856case the conversion routines don't handle. Drat.
857
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LW
858=item Execution of %s aborted due to compilation errors.
859
860(F) The final summary message when a Perl compilation fails.
861
862=item Exiting eval via %s
863
864(W) You are exiting an eval by unconventional means, such as a
865a goto, or a loop control statement.
866
867=item Exiting subroutine via %s
868
869(W) You are exiting a subroutine by unconventional means, such as a
870a goto, or a loop control statement.
871
872=item Exiting substitution via %s
873
874(W) You are exiting a substitution by unconventional means, such as a
875a return, a goto, or a loop control statement.
876
748a9306 877=item Fatal VMS error at %s, line %d
a0d0e21e 878
748a9306
LW
879(P) An error peculiar to VMS. Something untoward happened in a VMS system
880service or RTL routine; Perl's exit status should provide more details. The
881filename in "at %s" and the line number in "line %d" tell you which section of
882the Perl source code is distressed.
a0d0e21e
LW
883
884=item fcntl is not implemented
885
886(F) Your machine apparently doesn't implement fcntl(). What is this, a
887PDP-11 or something?
888
889=item Filehandle %s never opened
890
891(W) An I/O operation was attempted on a filehandle that was never initialized.
892You need to do an open() or a socket() call, or call a constructor from
893the FileHandle package.
894
895=item Filehandle %s opened only for input
896
897(W) You tried to write on a read-only filehandle. If you
898intended it to be a read-write filehandle, you needed to open it with
899"+<" or "+>" or "+>>" instead of with "<" or nothing. If you only
900intended to write the file, use ">" or ">>". See L<perlfunc/open>.
901
902=item Filehandle only opened for input
903
904(W) You tried to write on a read-only filehandle. If you
905intended it to be a read-write filehandle, you needed to open it with
906"+<" or "+>" or "+>>" instead of with "<" or nothing. If you only
907intended to write the file, use ">" or ">>". See L<perlfunc/open>.
908
909=item Final $ should be \$ or $name
910
911(F) You must now decide whether the final $ in a string was meant to be
912a literal dollar sign, or was meant to introduce a variable name
913that happens to be missing. So you have to put either the backslash or
914the name.
915
916=item Final @ should be \@ or @name
917
918(F) You must now decide whether the final @ in a string was meant to be
919a literal "at" sign, or was meant to introduce a variable name
920that happens to be missing. So you have to put either the backslash or
921the name.
922
923=item Format %s redefined
924
925(W) You redefined a format. To suppress this warning, say
926
927 {
928 local $^W = 0;
929 eval "format NAME =...";
930 }
931
932=item Format not terminated
933
934(F) A format must be terminated by a line with a solitary dot. Perl got
935to the end of your file without finding such a line.
936
937=item Found = in conditional, should be ==
938
939(W) You said
940
941 if ($foo = 123)
942
943when you meant
944
945 if ($foo == 123)
946
947(or something like that).
948
949=item gdbm store returned %d, errno %d, key "%s"
950
951(S) A warning from the GDBM_File extension that a store failed.
952
953=item gethostent not implemented
954
955(F) Your C library apparently doesn't implement gethostent(), probably
956because if it did, it'd feel morally obligated to return every hostname
957on the Internet.
958
959=item get{sock,peer}name() on closed fd
960
961(W) You tried to get a socket or peer socket name on a closed socket.
962Did you forget to check the return value of your socket() call?
963
748a9306
LW
964=item getpwnam returned invalid UIC %#o for user "%s"
965
966(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
967C<getpwnam> operator returned an invalid UIC.
968
969
a0d0e21e
LW
970=item Glob not terminated
971
972(F) The lexer saw a left angle bracket in a place where it was expecting
973a term, so it's looking for the corresponding right angle bracket, and not
974finding it. Chances are you left some needed parentheses out earlier in
975the line, and you really meant a "less than".
976
977=item Global symbol "%s" requires explicit package name
978
979(F) You've said "use strict vars", which indicates that all variables must
980either be lexically scoped (using "my"), or explicitly qualified to
981say which package the global variable is in (using "::").
982
983=item goto must have label
984
985(F) Unlike with "next" or "last", you're not allowed to goto an
986unspecified destination. See L<perlfunc/goto>.
987
988=item Had to create %s unexpectedly
989
990(S) A routine asked for a symbol from a symbol table that ought to have
991existed already, but for some reason it didn't, and had to be created on
992an emergency basis to prevent a core dump.
993
994=item Hash %%s missing the % in argument %d of %s()
995
996(D) Really old Perl let you omit the % on hash names in some spots. This
997is now heavily deprecated.
998
2ba9eb46 999=item Name "%s::%s" used only once: possible typo
a0d0e21e 1000
2ba9eb46
PP
1001(W) Typographical errors often show up as unique variable names. If you
1002had a good reason for having a unique name, then just mention it
1003again somehow to suppress the message (the C<use vars> pragma is
1004provided for just this purpose).
a0d0e21e
LW
1005
1006=item Illegal division by zero
1007
1008(F) You tried to divide a number by 0. Either something was wrong in your
1009logic, or you need to put a conditional in to guard against meaningless input.
1010
1011=item Illegal modulus zero
1012
1013(F) You tried to divide a number by 0 to get the remainder. Most numbers
1014don't take to this kindly.
1015
1016=item Illegal octal digit
1017
1018(F) You used an 8 or 9 in a octal number.
1019
748a9306
LW
1020=item Illegal octal digit ignored
1021
1022(W) You may have tried to use an 8 or 9 in a octal number. Interpretation
1023of the octal number stopped before the 8 or 9.
1024
a0d0e21e
LW
1025=item Insecure dependency in %s
1026
1027(F) You tried to do something that the tainting mechanism didn't like.
1028The tainting mechanism is turned on when you're running setuid or setgid,
1029or when you specify B<-T> to turn it on explicitly. The tainting mechanism
1030labels all data that's derived directly or indirectly from the user,
1031who is considered to be unworthy of your trust. If any such data is
1032used in a "dangerous" operation, you get this error. See L<perlsec>
1033for more information.
1034
1035=item Insecure directory in %s
1036
1037(F) You can't use system(), exec(), or a piped open in a setuid or setgid
1038script if $ENV{PATH} contains a directory that is writable by the world.
1039See L<perlsec>.
1040
1041=item Insecure PATH
1042
1043(F) You can't use system(), exec(), or a piped open in a setuid or
1044setgid script if $ENV{PATH} is derived from data supplied (or
1045potentially supplied) by the user. The script must set the path to a
1046known value, using trustworthy data. See L<perlsec>.
1047
748a9306
LW
1048=item Internal inconsistency in tracking vforks
1049
1050(S) A warning peculiar to VMS. Perl keeps track of the number
1051of times you've called C<fork> and C<exec>, in order to determine
2ba9eb46 1052whether the current call to C<exec> should affect the current
748a9306
LW
1053script or a subprocess (see L<perlvms/exec>). Somehow, this count
1054has become scrambled, so Perl is making a guess and treating
1055this C<exec> as a request to terminate the Perl script
1056and execute the specified command.
1057
a0d0e21e
LW
1058=item internal disaster in regexp
1059
1060(P) Something went badly wrong in the regular expression parser.
1061
1062=item internal urp in regexp at /%s/
1063
1064(P) Something went badly awry in the regular expression parser.
1065
1066=item invalid [] range in regexp
1067
1068(F) The range specified in a character class had a minimum character
1069greater than the maximum character. See L<perlre>.
1070
1071=item ioctl is not implemented
1072
1073(F) Your machine apparently doesn't implement ioctl(), which is pretty
1074strange for a machine that supports C.
1075
1076=item junk on end of regexp
1077
1078(P) The regular expression parser is confused.
1079
1080=item Label not found for "last %s"
1081
1082(F) You named a loop to break out of, but you're not currently in a
1083loop of that name, not even if you count where you were called from.
1084See L<perlfunc/last>.
1085
1086=item Label not found for "next %s"
1087
1088(F) You named a loop to continue, but you're not currently in a loop of
1089that name, not even if you count where you were called from. See
1090L<perlfunc/last>.
1091
1092=item Label not found for "redo %s"
1093
1094(F) You named a loop to restart, but you're not currently in a loop of
1095that name, not even if you count where you were called from. See
1096L<perlfunc/last>.
1097
1098=item listen() on closed fd
1099
1100(W) You tried to do a listen on a closed socket. Did you forget to check
1101the return value of your socket() call? See L<perlfunc/listen>.
1102
1103=item Literal @%s now requires backslash
1104
1105(F) It used to be that Perl would try to guess whether you wanted an
1106array interpolated or a literal @. It did this when the string was
1107first used at runtime. Now strings are parsed at compile time, and
1108ambiguous instances of @ must be disambiguated, either by putting a
1109backslash to indicate a literal, or by declaring (or using) the array
1110within the program before the string (lexically). (Someday it will simply
1111assume that an unbackslashed @ interpolates an array.)
1112
1113=item Method for operation %s not found in package %s during blessing
1114
1115(F) An attempt was made to specify an entry in an overloading table that
1116doesn't somehow point to a valid method. See L<perlovl>.
1117
1118=item Might be a runaway multi-line %s string starting on line %d
1119
1120(S) An advisory indicating that the previous error may have been caused
1121by a missing delimiter on a string or pattern, because it eventually
1122ended earlier on the current line.
1123
1124=item Misplaced _ in number
1125
1126(W) An underline in a decimal constant wasn't on a 3-digit boundary.
1127
1128=item Missing $ on loop variable
1129
1130(F) Apparently you've been programming in csh too much. Variables are always
1131mentioned with the $ in Perl, unlike in the shells, where it can vary from
1132one line to the next.
1133
1134=item Missing comma after first argument to %s function
1135
1136(F) While certain functions allow you to specify a filehandle or an
1137"indirect object" before the argument list, this ain't one of them.
1138
748a9306
LW
1139=item Missing operator before %s?
1140
1141(S) This is an educated guess made in conjunction with the message "%s
1142found where operator expected". Often the missing operator is a comma.
1143
a0d0e21e
LW
1144=item Missing right bracket
1145
1146(F) The lexer counted more opening curly brackets (braces) than closing ones.
1147As a general rule, you'll find it's missing near the place you were last
1148editing.
1149
1150=item Missing semicolon on previous line?
1151
1152(S) This is an educated guess made in conjunction with the message "%s
1153found where operator expected". Don't automatically put a semicolon on
1154the previous line just because you saw this message.
1155
1156=item Modification of a read-only value attempted
1157
1158(F) You tried, directly or indirectly, to change the value of a
1159constant. You didn't, of course, try "2 = 1", since the compiler
1160catches that. But an easy way to do the same thing is:
1161
1162 sub mod { $_[0] = 1 }
1163 mod(2);
1164
1165Another way is to assign to a substr() that's off the end of the string.
1166
1167=item Modification of non-creatable array value attempted, subscript %d
1168
1169(F) You tried to make an array value spring into existence, and the
1170subscript was probably negative, even counting from end of the array
1171backwards.
1172
1173=item Modification of non-creatable hash value attempted, subscript "%s"
1174
1175(F) You tried to make a hash value spring into existence, and it couldn't
1176be created for some peculiar reason.
1177
1178=item Module name must be constant
1179
1180(F) Only a bare module name is allowed as the first argument to a "use".
1181
1182=item msg%s not implemented
1183
1184(F) You don't have System V message IPC on your system.
1185
1186=item Multidimensional syntax %s not supported
1187
1188(W) Multidimensional arrays aren't written like $foo[1,2,3]. They're written
1189like $foo[1][2][3], as in C.
1190
1191=item Negative length
1192
1193(F) You tried to do a read/write/send/recv operation with a buffer length
1194that is less than 0. This is difficult to imagine.
1195
1196=item nested *?+ in regexp
1197
1198(F) You can't quantify a quantifier without intervening parens. So
1199things like ** or +* or ?* are illegal.
1200
1201Note, however, that the minimal matching quantifiers, *?, +? and ?? appear
1202to be nested quantifiers, but aren't. See L<perlre>.
1203
1204=item No #! line
1205
1206(F) The setuid emulator requires that scripts have a well-formed #! line
1207even on machines that don't support the #! construct.
1208
1209=item No %s allowed while running setuid
1210
1211(F) Certain operations are deemed to be too insecure for a setuid or setgid
1212script to even be allowed to attempt. Generally speaking there will be
1213another way to do what you want that is, if not secure, at least securable.
1214See L<perlsec>.
1215
1216=item No B<-e> allowed in setuid scripts
1217
1218(F) A setuid script can't be specified by the user.
1219
1220=item No comma allowed after %s
1221
1222(F) A list operator that has a filehandle or "indirect object" is not
1223allowed to have a comma between that and the following arguments.
1224Otherwise it'd be just another one of the arguments.
1225
748a9306
LW
1226=item No command into which to pipe on command line
1227
1228(F) An error peculiar to VMS. Perl handles its own command line redirection,
1229and found a '|' at the end of the command line, so it doesn't know whither you
1230want to pipe the output from this command.
1231
a0d0e21e
LW
1232=item No DB::DB routine defined
1233
1234(F) The currently executing code was compiled with the B<-d> switch,
1235but for some reason the perl5db.pl file (or some facsimile thereof)
1236didn't define a routine to be called at the beginning of each
1237statement. Which is odd, because the file should have been required
1238automatically, and should have blown up the require if it didn't parse
1239right.
1240
1241=item No dbm on this machine
1242
1243(P) This is counted as an internal error, because every machine should
1244supply dbm nowadays, since Perl comes with SDBM. See L<SDBM_File>.
1245
1246=item No DBsub routine
1247
1248(F) The currently executing code was compiled with the B<-d> switch,
1249but for some reason the perl5db.pl file (or some facsimile thereof)
1250didn't define a DB::sub routine to be called at the beginning of each
1251ordinary subroutine call.
1252
748a9306
LW
1253=item No error file after 2> or 2>> on command line
1254
1255(F) An error peculiar to VMS. Perl handles its own command line redirection,
1256and found a '2>' or a '2>>' on the command line, but can't find the name of the
1257file to which to write data destined for stderr.
1258
1259=item No input file after < on command line
1260
1261(F) An error peculiar to VMS. Perl handles its own command line redirection,
1262and found a '<' on the command line, but can't find the name of the file from
1263which to read data for stdin.
1264
1265=item No output file after > on command line
1266
1267(F) An error peculiar to VMS. Perl handles its own command line redirection,
1268and found a lone '>' at the end of the command line, so it doesn't know whither
1269you wanted to redirect stdout.
1270
1271=item No output file after > or >> on command line
1272
1273(F) An error peculiar to VMS. Perl handles its own command line redirection,
1274and found a '>' or a '>>' on the command line, but can't find the name of the
1275file to which to write data destined for stdout.
1276
a0d0e21e
LW
1277=item No Perl script found in input
1278
1279(F) You called C<perl -x>, but no line was found in the file beginning
1280with #! and containing the word "perl".
1281
1282=item No setregid available
1283
1284(F) Configure didn't find anything resembling the setregid() call for
1285your system.
1286
1287=item No setreuid available
1288
1289(F) Configure didn't find anything resembling the setreuid() call for
1290your system.
1291
1292=item No space allowed after B<-I>
1293
1294(F) The argument to B<-I> must follow the B<-I> immediately with no
1295intervening space.
1296
748a9306
LW
1297=item No such pipe open
1298
1299(P) An error peculiar to VMS. The internal routine my_pclose() tried to
1300close a pipe which hadn't been opened. This should have been caught earlier as
1301an attempt to close an unopened filehandle.
1302
a0d0e21e
LW
1303=item No such signal: SIG%s
1304
1305(W) You specified a signal name as a subscript to %SIG that was not recognized.
1306Say C<kill -l> in your shell to see the valid signal names on your system.
1307
1308=item Not a CODE reference
1309
1310(F) Perl was trying to evaluate a reference to a code value (that is, a
1311subroutine), but found a reference to something else instead. You can
1312use the ref() function to find out what kind of ref it really was.
1313See also L<perlref>.
1314
1315=item Not a format reference
1316
1317(F) I'm not sure how you managed to generate a reference to an anonymous
1318format, but this indicates you did, and that it didn't exist.
1319
1320=item Not a GLOB reference
1321
1322(F) Perl was trying to evaluate a reference to a "type glob" (that is,
1323a symbol table entry that looks like C<*foo>), but found a reference to
1324something else instead. You can use the ref() function to find out
1325what kind of ref it really was. See L<perlref>.
1326
1327=item Not a HASH reference
1328
1329(F) Perl was trying to evaluate a reference to a hash value, but
1330found a reference to something else instead. You can use the ref()
1331function to find out what kind of ref it really was. See L<perlref>.
1332
1333=item Not a perl script
1334
1335(F) The setuid emulator requires that scripts have a well-formed #! line
1336even on machines that don't support the #! construct. The line must
1337mention perl.
1338
1339=item Not a SCALAR reference
1340
1341(F) Perl was trying to evaluate a reference to a scalar value, but
1342found a reference to something else instead. You can use the ref()
1343function to find out what kind of ref it really was. See L<perlref>.
1344
1345=item Not a subroutine reference
1346
1347(F) Perl was trying to evaluate a reference to a code value (that is, a
1348subroutine), but found a reference to something else instead. You can
1349use the ref() function to find out what kind of ref it really was.
1350See also L<perlref>.
1351
1352=item Not a subroutine reference in %OVERLOAD
1353
1354(F) An attempt was made to specify an entry in an overloading table that
1355doesn't somehow point to a valid subroutine. See L<perlovl>.
1356
1357=item Not an ARRAY reference
1358
1359(F) Perl was trying to evaluate a reference to an array value, but
1360found a reference to something else instead. You can use the ref()
1361function to find out what kind of ref it really was. See L<perlref>.
1362
1363=item Not enough arguments for %s
1364
1365(F) The function requires more arguments than you specified.
1366
1367=item Not enough format arguments
1368
1369(W) A format specified more picture fields than the next line supplied.
1370See L<perlform>.
1371
1372=item Null filename used
1373
1374(F) You can't require the null filename, especially since on many machines
1375that means the current directory! See L<perlfunc/require>.
1376
1377=item NULL OP IN RUN
1378
1379(P) Some internal routine called run() with a null opcode pointer.
1380
1381=item Null realloc
1382
1383(P) An attempt was made to realloc NULL.
1384
1385=item NULL regexp argument
1386
1387(P) The internal pattern matching routines blew it bigtime.
1388
1389=item NULL regexp parameter
1390
1391(P) The internal pattern matching routines are out of their gourd.
1392
1393=item Odd number of elements in hash list
1394
1395(S) You specified an odd number of elements to a hash list, which is odd,
1396since hash lists come in key/value pairs.
1397
1398=item oops: oopsAV
1399
1400(S) An internal warning that the grammar is screwed up.
1401
1402=item oops: oopsHV
1403
1404(S) An internal warning that the grammar is screwed up.
1405
1406=item Operation `%s' %s: no method found,
1407
1408(F) An attempt was made to use an entry in an overloading table that
1409somehow no longer points to a valid method. See L<perlovl>.
1410
748a9306
LW
1411=item Operator or semicolon missing before %s
1412
1413(S) You used a variable or subroutine call where the parser was
1414expecting an operator. The parser has assumed you really meant
1415to use an operator, but this is highly likely to be incorrect.
1416For example, if you say "*foo *foo" it will be interpreted as
1417if you said "*foo * 'foo'".
1418
a0d0e21e
LW
1419=item Out of memory for yacc stack
1420
1421(F) The yacc parser wanted to grow its stack so it could continue parsing,
1422but realloc() wouldn't give it more memory, virtual or otherwise.
1423
1424=item Out of memory!
1425
1426(X) The malloc() function returned 0, indicating there was insufficient
1427remaining memory (or virtual memory) to satisfy the request.
1428
1429=item page overflow
1430
1431(W) A single call to write() produced more lines than can fit on a page.
1432See L<perlform>.
1433
1434=item panic: ck_grep
1435
1436(P) Failed an internal consistency check trying to compile a grep.
1437
1438=item panic: ck_split
1439
1440(P) Failed an internal consistency check trying to compile a split.
1441
1442=item panic: corrupt saved stack index
1443
1444(P) The savestack was requested to restore more localized values than there
1445are in the savestack.
1446
1447=item panic: die %s
1448
1449(P) We popped the context stack to an eval context, and then discovered
1450it wasn't an eval context.
1451
1452=item panic: do_match
1453
1454(P) The internal pp_match() routine was called with invalid operational data.
1455
1456=item panic: do_split
1457
1458(P) Something terrible went wrong in setting up for the split.
1459
1460=item panic: do_subst
1461
1462(P) The internal pp_subst() routine was called with invalid operational data.
1463
1464=item panic: do_trans
1465
1466(P) The internal do_trans() routine was called with invalid operational data.
1467
1468=item panic: goto
1469
1470(P) We popped the context stack to a context with the specified label,
1471and then discovered it wasn't a context we know how to do a goto in.
1472
1473=item panic: INTERPCASEMOD
1474
1475(P) The lexer got into a bad state at a case modifier.
1476
1477=item panic: INTERPCONCAT
1478
1479(P) The lexer got into a bad state parsing a string with brackets.
1480
1481=item panic: last
1482
1483(P) We popped the context stack to a block context, and then discovered
1484it wasn't a block context.
1485
1486=item panic: leave_scope clearsv
1487
1488(P) A writable lexical variable became readonly somehow within the scope.
1489
1490=item panic: leave_scope inconsistency
1491
1492(P) The savestack probably got out of sync. At least, there was an
1493invalid enum on the top of it.
1494
1495=item panic: malloc
1496
1497(P) Something requested a negative number of bytes of malloc.
1498
1499=item panic: mapstart
1500
1501(P) The compiler is screwed up with respect to the map() function.
1502
1503=item panic: null array
1504
1505(P) One of the internal array routines was passed a null AV pointer.
1506
1507=item panic: pad_alloc
1508
1509(P) The compiler got confused about which scratch pad it was allocating
1510and freeing temporaries and lexicals from.
1511
1512=item panic: pad_free curpad
1513
1514(P) The compiler got confused about which scratch pad it was allocating
1515and freeing temporaries and lexicals from.
1516
1517=item panic: pad_free po
1518
1519(P) An invalid scratch pad offset was detected internally.
1520
1521=item panic: pad_reset curpad
1522
1523(P) The compiler got confused about which scratch pad it was allocating
1524and freeing temporaries and lexicals from.
1525
1526=item panic: pad_sv po
1527
1528(P) An invalid scratch pad offset was detected internally.
1529
1530=item panic: pad_swipe curpad
1531
1532(P) The compiler got confused about which scratch pad it was allocating
1533and freeing temporaries and lexicals from.
1534
1535=item panic: pad_swipe po
1536
1537(P) An invalid scratch pad offset was detected internally.
1538
1539=item panic: pp_iter
1540
1541(P) The foreach iterator got called in a non-loop context frame.
1542
1543=item panic: realloc
1544
1545(P) Something requested a negative number of bytes of realloc.
1546
1547=item panic: restartop
1548
1549(P) Some internal routine requested a goto (or something like it), and
1550didn't supply the destination.
1551
1552=item panic: return
1553
1554(P) We popped the context stack to a subroutine or eval context, and
1555then discovered it wasn't a subroutine or eval context.
1556
1557=item panic: scan_num
1558
1559(P) scan_num() got called on something that wasn't a number.
1560
1561=item panic: sv_insert
1562
1563(P) The sv_insert() routine was told to remove more string than there
1564was string.
1565
1566=item panic: top_env
1567
1568(P) The compiler attempted to do a goto, or something weird like that.
1569
1570=item panic: yylex
1571
1572(P) The lexer got into a bad state while processing a case modifier.
1573
1574=item Parens missing around "%s" list
1575
1576(W) You said something like
1577
1578 my $foo, $bar = @_;
1579
1580when you meant
1581
1582 my ($foo, $bar) = @_;
1583
1584Remember that "my" and "local" bind closer than comma.
1585
1586=item Perl %3.3f required--this is only version %s, stopped
1587
1588(F) The module in question uses features of a version of Perl more recent
1589than the currently running version. How long has it been since you upgraded,
1590anyway? See L<perlfunc/require>.
1591
1592=item Permission denied
1593
1594(F) The setuid emulator in suidperl decided you were up to no good.
1595
748a9306
LW
1596=item pid %d not a child
1597
1598(W) A warning peculiar to VMS. Waitpid() was asked to wait for a process which
1599isn't a subprocess of the current process. While this is fine from VMS'
1600perspective, it's probably not what you intended.
1601
a0d0e21e
LW
1602=item POSIX getpgrp can't take an argument
1603
1604(F) Your C compiler uses POSIX getpgrp(), which takes no argument, unlike
1605the BSD version, which takes a pid.
1606
1607=item Possible memory corruption: %s overflowed 3rd argument
1608
1609(F) An ioctl() or fcntl() returned more than Perl was bargaining for.
1610Perl guesses a reasonable buffer size, but puts a sentinel byte at the
1611end of the buffer just in case. This sentinel byte got clobbered, and
1612Perl assumes that memory is now corrupted. See L<perlfunc/ioctl>.
1613
1614=item Precedence problem: open %s should be open(%s)
1615
1616(S) The old irregular construct
cb1a09d0 1617
a0d0e21e
LW
1618 open FOO || die;
1619
1620is now misinterpreted as
1621
1622 open(FOO || die);
1623
1624because of the strict regularization of Perl 5's grammar into unary and
1625list operators. (The old open was a little of both.) You must put
1626parens around the filehandle, or use the new "or" operator instead of "||".
1627
1628=item print on closed filehandle %s
1629
1630(W) The filehandle you're printing on got itself closed sometime before now.
1631Check your logic flow.
1632
1633=item printf on closed filehandle %s
1634
1635(W) The filehandle you're writing to got itself closed sometime before now.
1636Check your logic flow.
1637
1638=item Probable precedence problem on %s
1639
1640(W) The compiler found a bare word where it expected a conditional,
1641which often indicates that an || or && was parsed as part of the
1642last argument of the previous construct, for example:
1643
1644 open FOO || die;
1645
4633a7c4
LW
1646=item Prototype mismatch: (%s) vs (%s)
1647
1648(S) The subroutine being defined had a predeclared (forward) declaration
1649with a different function prototype.
1650
a0d0e21e
LW
1651=item Read on closed filehandle <%s>
1652
1653(W) The filehandle you're reading from got itself closed sometime before now.
1654Check your logic flow.
1655
1656=item Reallocation too large: %lx
1657
1658(F) You can't allocate more than 64K on an MSDOS machine.
1659
1660=item Recompile perl with B<-D>DEBUGGING to use B<-D> switch
1661
1662(F) You can't use the B<-D> option unless the code to produce the
1663desired output is compiled into Perl, which entails some overhead,
1664which is why it's currently left out of your copy.
1665
1666=item Recursive inheritance detected
1667
1668(F) More than 100 levels of inheritance were used. Probably indicates
1669an unintended loop in your inheritance hierarchy.
1670
1671=item Reference miscount in sv_replace()
1672
1673(W) The internal sv_replace() function was handed a new SV with a
1674reference count of other than 1.
1675
1676=item regexp memory corruption
1677
1678(P) The regular expression engine got confused by what the regular
1679expression compiler gave it.
1680
1681=item regexp out of space
1682
1683(P) A "can't happen" error, because safemalloc() should have caught it earlier.
1684
1685=item regexp too big
1686
2ba9eb46 1687(F) The current implementation of regular expressions uses shorts as
a0d0e21e
LW
1688address offsets within a string. Unfortunately this means that if
1689the regular expression compiles to longer than 32767, it'll blow up.
1690Usually when you want a regular expression this big, there is a better
1691way to do it with multiple statements. See L<perlre>.
1692
1693=item Reversed %s= operator
1694
1695(W) You wrote your assignment operator backwards. The = must always
1696comes last, to avoid ambiguity with subsequent unary operators.
1697
1698=item Runaway format
1699
1700(F) Your format contained the ~~ repeat-until-blank sequence, but it
1701produced 200 lines at once, and the 200th line looked exactly like the
1702199th line. Apparently you didn't arrange for the arguments to exhaust
1703themselves, either by using ^ instead of @ (for scalar variables), or by
1704shifting or popping (for array variables). See L<perlform>.
1705
1706=item Scalar value @%s[%s] better written as $%s[%s]
1707
1708(W) You've used an array slice (indicated by @) to select a single value of
1709an array. Generally it's better to ask for a scalar value (indicated by $).
1710The difference is that $foo[&bar] always behaves like a scalar, both when
1711assigning to it and when evaluating its argument, while @foo[&bar] behaves
1712like a list when you assign to it, and provides a list context to its
1713subscript, which can do weird things if you're only expecting one subscript.
1714
748a9306
LW
1715On the other hand, if you were actually hoping to treat the array
1716element as a list, you need to look into how references work, since
1717Perl will not magically convert between scalars and lists for you. See
1718L<perlref>.
1719
a0d0e21e
LW
1720=item Script is not setuid/setgid in suidperl
1721
1722(F) Oddly, the suidperl program was invoked on a script with its setuid
1723or setgid bit set. This doesn't make much sense.
1724
1725=item Search pattern not terminated
1726
1727(F) The lexer couldn't find the final delimiter of a // or m{}
1728construct. Remember that bracketing delimiters count nesting level.
1729
1730=item seek() on unopened file
1731
1732(W) You tried to use the seek() function on a filehandle that was either
1733never opened or has been closed since.
1734
1735=item select not implemented
1736
1737(F) This machine doesn't implement the select() system call.
1738
1739=item sem%s not implemented
1740
1741(F) You don't have System V semaphore IPC on your system.
1742
1743=item semi-panic: attempt to dup freed string
1744
1745(S) The internal newSVsv() routine was called to duplicate a scalar
1746that had previously been marked as free.
1747
1748=item Semicolon seems to be missing
1749
1750(W) A nearby syntax error was probably caused by a missing semicolon,
1751or possibly some other missing operator, such as a comma.
1752
1753=item Send on closed socket
1754
1755(W) The filehandle you're sending to got itself closed sometime before now.
1756Check your logic flow.
1757
1758=item Sequence (?#... not terminated
1759
1760(F) A regular expression comment must be terminated by a closing
1761parenthesis. Embedded parens aren't allowed. See L<perlre>.
1762
1763=item Sequence (?%s...) not implemented
1764
1765(F) A proposed regular expression extension has the character reserved
1766but has not yet been written. See L<perlre>.
1767
1768=item Sequence (?%s...) not recognized
1769
1770(F) You used a regular expression extension that doesn't make sense.
1771See L<perlre>.
1772
a5f75d66
AD
1773=item Server error
1774
1775Also known as "500 Server error". This is a CGI error, not a Perl
1776error. You need to make sure your script is executable, is accessible
1777by the user CGI is running the script under (which is probably not
1778the user account you tested it under), does not rely on any environment
1779variables (like PATH) from the user it isn't running under, and isn't
1780in a location where the CGI server can't find it, basically, more or less.
1781
a0d0e21e
LW
1782=item setegid() not implemented
1783
1784(F) You tried to assign to $), and your operating system doesn't support
1785the setegid() system call (or equivalent), or at least Configure didn't
1786think so.
1787
1788=item seteuid() not implemented
1789
1790(F) You tried to assign to $>, and your operating system doesn't support
1791the seteuid() system call (or equivalent), or at least Configure didn't
1792think so.
1793
1794=item setrgid() not implemented
1795
1796(F) You tried to assign to $(, and your operating system doesn't support
1797the setrgid() system call (or equivalent), or at least Configure didn't
1798think so.
1799
1800=item setruid() not implemented
1801
1802(F) You tried to assign to $<, and your operating system doesn't support
1803the setruid() system call (or equivalent), or at least Configure didn't
1804think so.
1805
1806=item Setuid/gid script is writable by world
1807
1808(F) The setuid emulator won't run a script that is writable by the world,
1809because the world might have written on it already.
1810
1811=item shm%s not implemented
1812
1813(F) You don't have System V shared memory IPC on your system.
1814
1815=item shutdown() on closed fd
1816
1817(W) You tried to do a shutdown on a closed socket. Seems a bit superfluous.
1818
1819=item SIG%s handler "%s" not defined.
1820
1821(W) The signal handler named in %SIG doesn't, in fact, exist. Perhaps you
1822put it into the wrong package?
1823
1824=item sort is now a reserved word
1825
1826(F) An ancient error message that almost nobody ever runs into anymore.
1827But before sort was a keyword, people sometimes used it as a filehandle.
1828
1829=item Sort subroutine didn't return a numeric value
1830
1831(F) A sort comparison routine must return a number. You probably blew
4633a7c4 1832it by not using C<E<lt>=E<gt>> or C<cmp>, or by not using them correctly.
a0d0e21e
LW
1833See L<perlfunc/sort>.
1834
1835=item Sort subroutine didn't return single value
1836
1837(F) A sort comparison subroutine may not return a list value with more
1838or less than one element. See L<perlfunc/sort>.
1839
1840=item Split loop
1841
1842(P) The split was looping infinitely. (Obviously, a split shouldn't iterate
1843more times than there are characters of input, which is what happened.)
1844See L<perlfunc/split>.
1845
1846=item Stat on unopened file <%s>
1847
1848(W) You tried to use the stat() function (or an equivalent file test)
1849on a filehandle that was either never opened or has been closed since.
1850
1851=item Statement unlikely to be reached
1852
1853(W) You did an exec() with some statement after it other than a die().
1854This is almost always an error, because exec() never returns unless
1855there was a failure. You probably wanted to use system() instead,
1856which does return. To suppress this warning, put the exec() in a block
1857by itself.
1858
1859=item Subroutine %s redefined
1860
1861(W) You redefined a subroutine. To suppress this warning, say
1862
1863 {
1864 local $^W = 0;
1865 eval "sub name { ... }";
1866 }
1867
1868=item Substitution loop
1869
1870(P) The substitution was looping infinitely. (Obviously, a
1871substitution shouldn't iterate more times than there are characters of
1872input, which is what happened.) See the discussion of substitution in
1873L<perlop/"Quote and Quotelike Operators">.
1874
1875=item Substitution pattern not terminated
1876
1877(F) The lexer couldn't find the interior delimiter of a s/// or s{}{}
1878construct. Remember that bracketing delimiters count nesting level.
1879
1880=item Substitution replacement not terminated
1881
1882(F) The lexer couldn't find the final delimiter of a s/// or s{}{}
1883construct. Remember that bracketing delimiters count nesting level.
1884
1885=item substr outside of string
1886
1887(W) You tried to reference a substr() that pointed outside of a string.
1888That is, the absolute value of the offset was larger than the length of
1889the string. See L<perlfunc/substr>.
1890
1891=item suidperl is no longer needed since...
1892
1893(F) Your Perl was compiled with B<-D>SETUID_SCRIPTS_ARE_SECURE_NOW, but a
1894version of the setuid emulator somehow got run anyway.
1895
1896=item syntax error
1897
1898(F) Probably means you had a syntax error. Common reasons include:
1899
1900 A keyword is misspelled.
1901 A semicolon is missing.
1902 A comma is missing.
1903 An opening or closing parenthesis is missing.
1904 An opening or closing brace is missing.
1905 A closing quote is missing.
1906
1907Often there will be another error message associated with the syntax
1908error giving more information. (Sometimes it helps to turn on B<-w>.)
1909The error message itself often tells you where it was in the line when
1910it decided to give up. Sometimes the actual error is several tokens
1911before this, since Perl is good at understanding random input.
1912Occasionally the line number may be misleading, and once in a blue moon
1913the only way to figure out what's triggering the error is to call
1914C<perl -c> repeatedly, chopping away half the program each time to see
1915if the error went away. Sort of the cybernetic version of S<20 questions>.
1916
cb1a09d0
AD
1917=item syntax error at line %d: `%s' unexpected
1918
1919(A) You've accidentally run your script through the Bourne shell
1920instead of Perl. Check the <#!> line, or manually feed your script
1921into Perl yourself.
1922
a0d0e21e
LW
1923=item System V IPC is not implemented on this machine
1924
1925(F) You tried to do something with a function beginning with "sem", "shm"
1926or "msg". See L<perlfunc/semctl>, for example.
1927
1928=item Syswrite on closed filehandle
1929
1930(W) The filehandle you're writing to got itself closed sometime before now.
1931Check your logic flow.
1932
1933=item tell() on unopened file
1934
1935(W) You tried to use the tell() function on a filehandle that was either
1936never opened or has been closed since.
1937
1938=item Test on unopened file <%s>
1939
1940(W) You tried to invoke a file test operator on a filehandle that isn't
1941open. Check your logic. See also L<perlfunc/-X>.
1942
1943=item That use of $[ is unsupported
1944
1945(F) Assignment to $[ is now strictly circumscribed, and interpreted as
1946a compiler directive. You may only say one of
1947
1948 $[ = 0;
1949 $[ = 1;
1950 ...
1951 local $[ = 0;
1952 local $[ = 1;
1953 ...
1954
1955This is to prevent the problem of one module changing the array base
1956out from under another module inadvertently. See L<perlvar/$[>.
1957
1958=item The %s function is unimplemented
1959
1960The function indicated isn't implemented on this architecture, according
1961to the probings of Configure.
1962
1963=item The crypt() function is unimplemented due to excessive paranoia.
1964
1965(F) Configure couldn't find the crypt() function on your machine,
1966probably because your vendor didn't supply it, probably because they
1967think the U.S. Govermnment thinks it's a secret, or at least that they
1968will continue to pretend that it is. And if you quote me on that, I
1969will deny it.
1970
1971=item The stat preceding C<-l _> wasn't an lstat
1972
1973(F) It makes no sense to test the current stat buffer for symbolic linkhood
1974if the last stat that wrote to the stat buffer already went past
1975the symlink to get to the real file. Use an actual filename instead.
1976
1977=item times not implemented
1978
1979(F) Your version of the C library apparently doesn't do times(). I suspect
1980you're not running on Unix.
1981
1982=item Too few args to syscall
1983
1984(F) There has to be at least one argument to syscall() to specify the
1985system call to call, silly dilly.
1986
cb1a09d0
AD
1987=item Too many ('s
1988
1989=item Too many )'s
1990
1991(A) You've accidentally run your script through B<csh> instead
1992of Perl. Check the <#!> line, or manually feed your script
1993into Perl yourself.
1994
a0d0e21e
LW
1995=item Too many args to syscall
1996
1997(F) Perl only supports a maximum of 14 args to syscall().
1998
1999=item Too many arguments for %s
2000
2001(F) The function requires fewer arguments than you specified.
2002
2003=item trailing \ in regexp
2004
2005(F) The regular expression ends with an unbackslashed backslash. Backslash
2006it. See L<perlre>.
2007
2008=item Translation pattern not terminated
2009
2010(F) The lexer couldn't find the interior delimiter of a tr/// or tr[][]
2011construct.
2012
2013=item Translation replacement not terminated
2014
2015(F) The lexer couldn't find the final delimiter of a tr/// or tr[][]
2016construct.
2017
2018=item truncate not implemented
2019
2020(F) Your machine doesn't implement a file truncation mechanism that
2021Configure knows about.
2022
2023=item Type of arg %d to %s must be %s (not %s)
2024
2025(F) This function requires the argument in that position to be of a
2026certain type. Arrays must be @NAME or @{EXPR}. Hashes must be
2027%NAME or %{EXPR}. No implicit dereferencing is allowed--use the
2028{EXPR} forms as an explicit dereference. See L<perlref>.
2029
2030=item umask: argument is missing initial 0
2031
2032(W) A umask of 222 is incorrect. It should be 0222, since octal literals
2033always start with 0 in Perl, as in C.
2034
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2035=item Unable to create sub named "%s"
2036
2037(F) You attempted to create or access a subroutine with an illegal name.
2038
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2039=item Unbalanced context: %d more PUSHes than POPs
2040
2041(W) The exit code detected an internal inconsistency in how many execution
2042contexts were entered and left.
2043
2044=item Unbalanced saves: %d more saves than restores
2045
2046(W) The exit code detected an internal inconsistency in how many
2047values were temporarily localized.
2048
2049=item Unbalanced scopes: %d more ENTERs than LEAVEs
2050
2051(W) The exit code detected an internal inconsistency in how many blocks
2052were entered and left.
2053
2054=item Unbalanced tmps: %d more allocs than frees
2055
2056(W) The exit code detected an internal inconsistency in how many mortal
2057scalars were allocated and freed.
2058
2059=item Undefined format "%s" called
2060
2061(F) The format indicated doesn't seem to exist. Perhaps it's really in
2062another package? See L<perlform>.
2063
2064=item Undefined sort subroutine "%s" called
2065
2066(F) The sort comparison routine specified doesn't seem to exist. Perhaps
2067it's in a different package? See L<perlfunc/sort>.
2068
2069=item Undefined subroutine &%s called
2070
2071(F) The subroutine indicated hasn't been defined, or if it was, it
2072has since been undefined.
2073
2074=item Undefined subroutine called
2075
2076(F) The anonymous subroutine you're trying to call hasn't been defined,
2077or if it was, it has since been undefined.
2078
2079=item Undefined subroutine in sort
2080
2081(F) The sort comparison routine specified is declared but doesn't seem to
2082have been defined yet. See L<perlfunc/sort>.
2083
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2084=item Undefined top format "%s" called
2085
2086(F) The format indicated doesn't seem to exist. Perhaps it's really in
2087another package? See L<perlform>.
2088
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2089=item unexec of %s into %s failed!
2090
2091(F) The unexec() routine failed for some reason. See your local FSF
2092representative, who probably put it there in the first place.
2093
2094=item Unknown BYTEORDER
2095
2096(F) There are no byteswapping functions for a machine with this byte order.
2097
2098=item unmatched () in regexp
2099
2100(F) Unbackslashed parentheses must always be balanced in regular
2101expressions. If you're a vi user, the % key is valuable for finding
2102the matching paren. See L<perlre>.
2103
2104=item Unmatched right bracket
2105
2106(F) The lexer counted more closing curly brackets (braces) than opening
2107ones, so you're probably missing an opening bracket. As a general
2108rule, you'll find the missing one (so to speak) near the place you were
2109last editing.
2110
2111=item unmatched [] in regexp
2112
2113(F) The brackets around a character class must match. If you wish to
2114include a closing bracket in a character class, backslash it or put it first.
2115See L<perlre>.
2116
2117=item Unquoted string "%s" may clash with future reserved word
2118
2119(W) You used a bare word that might someday be claimed as a reserved word.
2120It's best to put such a word in quotes, or capitalize it somehow, or insert
2121an underbar into it. You might also declare it as a subroutine.
2122
2123=item Unrecognized character \%03o ignored
2124
2125(S) A garbage character was found in the input, and ignored, in case it's
2126a weird control character on an EBCDIC machine, or some such.
2127
2128=item Unrecognized signal name "%s"
2129
2130(F) You specified a signal name to the kill() function that was not recognized.
2131Say C<kill -l> in your shell to see the valid signal names on your system.
2132
2133=item Unrecognized switch: -%s
2134
2135(F) You specified an illegal option to Perl. Don't do that.
2136(If you think you didn't do that, check the #! line to see if it's
2137supplying the bad switch on your behalf.)
2138
2139=item Unsuccessful %s on filename containing newline
2140
2141(W) A file operation was attempted on a filename, and that operation
2142failed, PROBABLY because the filename contained a newline, PROBABLY
2143because you forgot to chop() or chomp() it off. See L<perlfunc/chop>.
2144
2145=item Unsupported directory function "%s" called
2146
2147(F) Your machine doesn't support opendir() and readdir().
2148
2149=item Unsupported function %s
2150
2151(F) This machines doesn't implement the indicated function, apparently.
2152At least, Configure doesn't think so.
2153
2154=item Unsupported socket function "%s" called
2155
2156(F) Your machine doesn't support the Berkeley socket mechanism, or at
2157least that's what Configure thought.
2158
2159=item Unterminated <> operator
2160
2161(F) The lexer saw a left angle bracket in a place where it was expecting
2162a term, so it's looking for the corresponding right angle bracket, and not
2163finding it. Chances are you left some needed parentheses out earlier in
2164the line, and you really meant a "less than".
2165
2166=item Use of $# is deprecated
2167
2168(D) This was an ill-advised attempt to emulate a poorly defined awk feature.
2169Use an explicit printf() or sprintf() instead.
2170
2171=item Use of $* is deprecated
2172
2173(D) This variable magically turned on multiline pattern matching, both for
2174you and for any luckless subroutine that you happen to call. You should
2175use the new C<//m> and C<//s> modifiers now to do that without the dangerous
2176action-at-a-distance effects of C<$*>.
2177
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2178=item Use of %s in printf format not supported
2179
2180(F) You attempted to use a feature of printf that is accessible only
2181from C. This usually means there's a better way to do it in Perl.
2182
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2183=item Use of %s is deprecated
2184
2185(D) The construct indicated is no longer recommended for use, generally
2186because there's a better way to do it, and also because the old way has
2187bad side effects.
2188
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LW
2189=item Use of bare << to mean <<"" is deprecated
2190
2191(D) You are now encouraged to use the explicitly quoted form if you
2192wish to use a blank line as the terminator of the here-document.
2193
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2194=item Use of implicit split to @_ is deprecated
2195
2196(D) It makes a lot of work for the compiler when you clobber a
2197subroutine's argument list, so it's better if you assign the results of
2198a split() explicitly to an array (or list).
2199
2200=item Use of uninitialized value
2201
2202(W) An undefined value was used as if it were already defined. It was
2203interpreted as a "" or a 0, but maybe it was a mistake. To suppress this
2204warning assign an initial value to your variables.
2205
2206=item Useless use of %s in void context
2207
2208(W) You did something without a side effect in a context that does nothing
2209with the return value, such as a statement that doesn't return a value
2210from a block, or the left side of a scalar comma operator. Very often
2211this points not to stupidity on your part, but a failure of Perl to parse
2212your program the way you thought it would. For example, you'd get this
2213if you mixed up your C precedence with Python precedence and said
2214
2215 $one, $two = 1, 2;
2216
2217when you meant to say
2218
2219 ($one, $two) = (1, 2);
2220
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LW
2221Another common error is to use ordinary parentheses to construct a list
2222reference when you should be using square or curly brackets, for
2223example, if you say
2224
2225 $array = (1,2);
2226
2227when you should have said
2228
2229 $array = [1,2];
2230
2231The square brackets explicitly turn a list value into a scalar value,
2232while parentheses do not. So when a parenthesized list is evaluated in
2233a scalar context, the comma is treated like C's comma operator, which
2234throws away the left argument, which is not what you want. See
2235L<perlref> for more on this.
2236
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2237=item Variable "%s" is not exported
2238
2239(F) While "use strict" in effect, you referred to a global variable
2240that you apparently thought was imported from another module, because
2241something else of the same name (usually a subroutine) is exported
2242by that module. It usually means you put the wrong funny character
2243on the front of your variable.
2244
cb1a09d0
AD
2245=item Variable syntax.
2246
2247(A) You've accidentally run your script through B<csh> instead
2248of Perl. Check the <#!> line, or manually feed your script
2249into Perl yourself.
2250
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2251=item Warning: unable to close filehandle %s properly.
2252
2253(S) The implicit close() done by an open() got an error indication on the
2ba9eb46 2254close(). This usually indicates your filesystem ran out of disk space.
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2255
2256=item Warning: Use of "%s" without parens is ambiguous
2257
2258(S) You wrote a unary operator followed by something that looks like a
2259binary operator that could also have been interpreted as a term or
2260unary operator. For instance, if you know that the rand function
2261has a default argument of 1.0, and you write
2262
2263 rand + 5;
2264
2265you may THINK you wrote the same thing as
2266
2267 rand() + 5;
2268
2269but in actual fact, you got
2270
2271 rand(+5);
2272
2273So put in parens to say what you really mean.
2274
2275=item Write on closed filehandle
2276
2277(W) The filehandle you're writing to got itself closed sometime before now.
2278Check your logic flow.
2279
2280=item X outside of string
2281
2282(F) You had a pack template that specified a relative position before
2283the beginning of the string being unpacked. See L<perlfunc/pack>.
2284
2285=item x outside of string
2286
2287(F) You had a pack template that specified a relative position after
2288the end of the string being unpacked. See L<perlfunc/pack>.
2289
2290=item Xsub "%s" called in sort
2291
2292(F) The use of an external subroutine as a sort comparison is not yet supported.
2293
2294=item Xsub called in sort
2295
2296(F) The use of an external subroutine as a sort comparison is not yet supported.
2297
2298=item You can't use C<-l> on a filehandle
2299
2300(F) A filehandle represents an opened file, and when you opened the file it
2301already went past any symlink you are presumably trying to look for.
2302Use a filename instead.
2303
2304=item YOU HAVEN'T DISABLED SET-ID SCRIPTS IN THE KERNEL YET!
2305
2306(F) And you probably never will, since you probably don't have the
2307sources to your kernel, and your vendor probably doesn't give a rip
2308about what you want. Your best bet is to use the wrapsuid script in
2309the eg directory to put a setuid C wrapper around your script.
2310
2311=item You need to quote "%s"
2312
2313(W) You assigned a bareword as a signal handler name. Unfortunately, you
2314already have a subroutine of that name declared, which means that Perl 5
2315will try to call the subroutine when the assignment is executed, which is
2316probably not what you want. (If it IS what you want, put an & in front.)
2317
2318=item [gs]etsockopt() on closed fd
2319
2320(W) You tried to get or set a socket option on a closed socket.
2321Did you forget to check the return value of your socket() call?
2322See L<perlfunc/getsockopt>.
2323
2324=item \1 better written as $1
2325
2326(W) Outside of patterns, backreferences live on as variables. The use
2327of backslashes is grandfathered on the righthand side of a
2328substitution, but stylistically it's better to use the variable form
2329because other Perl programmers will expect it, and it works better
2330if there are more than 9 backreferences.
2331
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LW
2332=item '|' and '<' may not both be specified on command line
2333
2334(F) An error peculiar to VMS. Perl does its own command line redirection, and
2335found that STDIN was a pipe, and that you also tried to redirect STDIN using
2336'<'. Only one STDIN stream to a customer, please.
2337
2338=item '|' and '>' may not both be specified on command line
2339
2340(F) An error peculiar to VMS. Perl does its own command line redirection, and
2341thinks you tried to redirect stdout both to a file and into a pipe to another
2342command. You need to choose one or the other, though nothing's stopping you
2343from piping into a program or Perl script which 'splits' output into two
2344streams, such as
2345
2346 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
2347 while (<STDIN>) {
2348 print;
2349 print OUT;
2350 }
2351 close OUT;
2352
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LW
2353=back
2354