This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Make pack-as-int/sprintf-%c-ing/chr-ring inf/nan fatal.
[perl5.git] / pod / perldiag.pod
CommitLineData
a0d0e21e
LW
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).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
a0d0e21e
LW
13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
e476b1b5
GS
20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
e476b1b5
GS
24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
e476b1b5
GS
27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
4438c4b7
JH
34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
6df41af2
GS
38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
a0d0e21e
LW
44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
be771a83
GS
49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
de42a5a9 53=item Allocation too large: %x
a0d0e21e 54
6df41af2 55(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 56
04f74579 57=item '%c' allowed only after types %s in %s
ef54e1a4 58
1109a392
MHM
59(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60after certain types. See L<perlfunc/pack>.
ef54e1a4 61
6df41af2 62=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 63
75b44862 64(W ambiguous) A subroutine you have declared has the same name as a Perl
be771a83
GS
65keyword, and you have used the name without qualification for calling
66one or the other. Perl decided to call the builtin because the
67subroutine is not imported.
43192e07 68
6df41af2
GS
69To force interpretation as a subroutine call, either put an ampersand
70before the subroutine name, or qualify the name with its package.
71Alternatively, you can import the subroutine (or pretend that it's
72imported with the C<use subs> pragma).
43192e07 73
6df41af2 74To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 75on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
be771a83
GS
76to be an object method (see L<perlsub/"Subroutine Attributes"> or
77L<attributes>).
43192e07 78
c2e66d9e
GS
79=item Ambiguous range in transliteration operator
80
81(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82all. To include a C<-> character in a transliteration, put it either
83first or last. (In the past, C<tr/a-z-0//> was synonymous with
84C<tr/a-y//>, which was probably not what you would have expected.)
85
6df41af2 86=item Ambiguous use of %s resolved as %s
43192e07 87
7c7af292 88(S ambiguous) You said something that may not be interpreted the way
6df41af2
GS
89you thought. Normally it's pretty easy to disambiguate it by supplying
90a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 91
591f5ca2
FC
92=item Ambiguous use of -%s resolved as -&%s()
93
94(S ambiguous) You wrote something like C<-foo>, which might be the
95string C<"-foo">, or a call to the function C<foo>, negated. If you meant
96the string, just write C<"-foo">. If you meant the function call,
97write C<-foo()>.
98
d8225693
JM
99=item Ambiguous use of %c resolved as operator %c
100
7c7af292 101(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
3303f755
FC
102bitwise and, and multiplication) I<and> initial special characters
103(denoting hashes, subroutines and typeglobs), and you said something
104like C<*foo * foo> that might be interpreted as either of them. We
105assumed you meant the infix operator, but please try to make it more
106clear -- in the example given, you might write C<*foo * foo()> if you
107really meant to multiply a glob by the result of calling a function.
d8225693 108
1ef43bca
JM
109=item Ambiguous use of %c{%s} resolved to %c%s
110
111(W ambiguous) You wrote something like C<@{foo}>, which might be
112asking for the variable C<@foo>, or it might be calling a function
113named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 114the variable, you can just write C<@foo>. If you wanted to call the
1ef43bca
JM
115function, write C<@{foo()}> ... or you could just not have a variable
116and a function with the same name, and save yourself a lot of trouble.
117
e850844c
FC
118=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
119
120=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 121
fa816bf3
FC
122(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
123the name of a Perl keyword), which might be looking for element number
1242 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
125might have meant to pass an anonymous arrayref to the function named
126foo, and then do a scalar deref on the value it returns. If you meant
127that, write C<${foo([2])}>.
ccaaf480
FC
128
129In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130to disambiguate between array subscripts and character classes.
fa816bf3
FC
131C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
132by the character class C<[2345]>. If an array subscript is what you
133want, you can avoid the warning by changing C</${length[2345]}/> to the
134unsightly C</${\$length[2345]}/>, by renaming your array to something
135that does not coincide with a built-in keyword, or by simply turning
136off warnings with C<no warnings 'ambiguous';>.
4da60377 137
6df41af2 138=item '|' and '<' may not both be specified on command line
a0d0e21e 139
be771a83
GS
140(F) An error peculiar to VMS. Perl does its own command line
141redirection, and found that STDIN was a pipe, and that you also tried to
142redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 143
6df41af2 144=item '|' and '>' may not both be specified on command line
1028017a 145
be771a83
GS
146(F) An error peculiar to VMS. Perl does its own command line
147redirection, and thinks you tried to redirect stdout both to a file and
148into a pipe to another command. You need to choose one or the other,
149though nothing's stopping you from piping into a program or Perl script
150which 'splits' output into two streams, such as
1028017a 151
6df41af2
GS
152 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
153 while (<STDIN>) {
154 print;
155 print OUT;
156 }
157 close OUT;
c9f97d15 158
6df41af2 159=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 160
496a33f5
SC
161(W misc) The pattern match (C<//>), substitution (C<s///>), and
162transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 163one of them to an array or a hash, it will convert the array or hash to
ac036724 164a scalar value (the length of an array, or the population info of a
165hash) and then work on that scalar value. This is probably not what
be771a83
GS
166you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
167alternatives.
eb6e2d6f 168
6df41af2 169=item Arg too short for msgsnd
76cd736e 170
6df41af2 171(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 172
f86702cc 173=item Argument "%s" isn't numeric%s
a0d0e21e 174
be771a83
GS
175(W numeric) The indicated string was fed as an argument to an operator
176that expected a numeric value instead. If you're fortunate the message
177will identify which operator was so unfortunate.
a0d0e21e 178
b4581f09
JH
179=item Argument list not closed for PerlIO layer "%s"
180
a534ac11
FC
181(W layer) When pushing a layer with arguments onto the Perl I/O
182system you forgot the ) that closes the argument list. (Layers
183take care of transforming data between external and internal
184representations.) Perl stopped parsing the layer list at this
185point and did not attempt to push this layer. If your program
186didn't explicitly request the failing operation, it may be the
187result of the value of the environment variable PERLIO.
b4581f09 188
3f7602fa
TC
189=item Argument "%s" treated as 0 in increment (++)
190
191(W numeric) The indicated string was fed as an argument to the C<++>
192operator which expects either a number or a string matching
193C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
194Auto-decrement> for details.
195
a0d0e21e
LW
196=item assertion botched: %s
197
21b5e840 198(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 199
0eacef8e 200=item Assertion %s failed: file "%s", line %d
a0d0e21e 201
21b5e840 202(X) A general assertion failed. The file in question must be examined.
a0d0e21e 203
82122228
FC
204=item Assigning non-zero to $[ is no longer possible
205
7d345e3d
FC
206(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
207the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 208
a0d0e21e
LW
209=item Assignment to both a list and a scalar
210
211(F) If you assign to a conditional operator, the 2nd and 3rd arguments
212must either both be scalars or both be lists. Otherwise Perl won't
213know which context to supply to the right side.
214
f51551f7
FC
215=item <> at require-statement should be quotes
216
217(F) You wrote C<< require <file> >> when you should have written
218C<require 'file'>.
219
2393f1b9 220=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 221
49293501 222(F) The failing code has attempted to get or set a key which is not in
2393f1b9 223the current set of allowed keys of a restricted hash.
49293501 224
dcdfe746
FC
225=item Attempt to bless into a freed package
226
227(F) You wrote C<bless $foo> with one argument after somehow causing
228the current package to be freed. Perl cannot figure out what to
229do, so it throws up in hands in despair.
230
81689caa
HS
231=item Attempt to bless into a reference
232
233(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 234the name of the package to bless the resulting object into. You've
81689caa
HS
235supplied instead a reference to something: perhaps you wrote
236
237 bless $self, $proto;
238
239when you intended
240
241 bless $self, ref($proto) || $proto;
242
243If you actually want to bless into the stringified version
244of the reference supplied, you need to stringify it yourself, for
245example by:
246
247 bless $self, "$proto";
248
a730510a
FC
249=item Attempt to clear deleted array
250
251(S debugging) An array was assigned to when it was being freed.
252Freed values are not supposed to be visible to Perl code. This
253can also happen if XS code calls C<av_clear> from a custom magic
254callback on the array.
255
96ebfdd7
RK
256=item Attempt to delete disallowed key '%s' from a restricted hash
257
258(F) The failing code attempted to delete from a restricted hash a key
259which is not in its key set.
260
261=item Attempt to delete readonly key '%s' from a restricted hash
262
263(F) The failing code attempted to delete a key whose value has been
264declared readonly from a restricted hash.
265
de42a5a9 266=item Attempt to free non-arena SV: 0x%x
a0d0e21e 267
f84fe999 268(S internal) All SV objects are supposed to be allocated from arenas
be771a83
GS
269that will be garbage collected on exit. An SV was discovered to be
270outside any of those arenas.
a0d0e21e 271
12578ffb 272=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 273
f84fe999 274(S internal) Perl maintains a reference-counted internal table of
be771a83
GS
275strings to optimize the storage and access of hash keys and other
276strings. This indicates someone tried to decrement the reference count
277of a string that can no longer be found in the table.
bbce6d69 278
7d5b40b4 279=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 280
f84fe999 281(S debugging) Mortalized values are supposed to be freed by the
be771a83
GS
282free_tmps() routine. This indicates that something else is freeing the
283SV before the free_tmps() routine gets a chance, which means that the
284free_tmps() routine will be freeing an unreferenced scalar when it does
285try to free it.
a0d0e21e
LW
286
287=item Attempt to free unreferenced glob pointers
288
f84fe999 289(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 290
7d5b40b4 291=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 292
8f7e4d2c 293(S internal) Perl went to decrement the reference count of a scalar to
be771a83
GS
294see if it would go to 0, and discovered that it had already gone to 0
295earlier, and should have been freed, and in fact, probably was freed.
296This could indicate that SvREFCNT_dec() was called too many times, or
297that SvREFCNT_inc() was called too few times, or that the SV was
298mortalized when it shouldn't have been, or that memory has been
299corrupted.
a0d0e21e 300
84902520
TB
301=item Attempt to pack pointer to temporary value
302
be771a83
GS
303(W pack) You tried to pass a temporary value (like the result of a
304function, or a computed expression) to the "p" pack() template. This
305means the result contains a pointer to a location that could become
306invalid anytime, even before the end of the current statement. Use
307literals or global values as arguments to the "p" pack() template to
308avoid this warning.
84902520 309
087b5369
RD
310=item Attempt to reload %s aborted.
311
312(F) You tried to load a file with C<use> or C<require> that failed to
313compile once already. Perl will not try to compile this file again
314unless you delete its entry from %INC. See L<perlfunc/require> and
315L<perlvar/%INC>.
316
1b20cd17
NC
317=item Attempt to set length of freed array
318
0c5c527f
FC
319(W misc) You tried to set the length of an array which has
320been freed. You can do this by storing a reference to the
321scalar representing the last index of an array and later
322assigning through that reference. For example
1b20cd17
NC
323
324 $r = do {my @a; \$#a};
325 $$r = 503
326
b7a902f4
PP
327=item Attempt to use reference as lvalue in substr
328
be771a83
GS
329(W substr) You supplied a reference as the first argument to substr()
330used as an lvalue, which is pretty strange. Perhaps you forgot to
331dereference it first. See L<perlfunc/substr>.
b7a902f4 332
c32124fe
NC
333=item Attribute "locked" is deprecated
334
57dedab9
FC
335(D deprecated) You have used the attributes pragma to modify the
336"locked" attribute on a code reference. The :locked attribute is
337obsolete, has had no effect since 5005 threads were removed, and
338will be removed in a future release of Perl 5.
c32124fe 339
591f5ca2
FC
340=item Attribute prototype(%s) discards earlier prototype attribute in same sub
341
342(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
343example. Since each sub can only have one prototype, the earlier
344declaration(s) are discarded while the last one is applied.
345
f1a3ce43
NC
346=item Attribute "unique" is deprecated
347
57dedab9
FC
348(D deprecated) You have used the attributes pragma to modify
349the "unique" attribute on an array, hash or scalar reference.
350The :unique attribute has had no effect since Perl 5.8.8, and
351will be removed in a future release of Perl 5.
f1a3ce43 352
ccce04a4
FC
353=item av_reify called on tied array
354
355(S debugging) This indicates that something went wrong and Perl got I<very>
356confused about C<@_> or C<@DB::args> being tied.
357
de42a5a9 358=item Bad arg length for %s, is %u, should be %d
a0d0e21e 359
be771a83
GS
360(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
361or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 362S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
a0d0e21e
LW
363S<sizeof(struct shmid_ds *)>.
364
7a95317d
GS
365=item Bad evalled substitution pattern
366
496a33f5 367(F) You've used the C</e> switch to evaluate the replacement for a
7a95317d
GS
368substitution, but perl found a syntax error in the code to evaluate,
369most likely an unexpected right brace '}'.
370
a0d0e21e
LW
371=item Bad filehandle: %s
372
be771a83
GS
373(F) A symbol was passed to something wanting a filehandle, but the
374symbol has no filehandle associated with it. Perhaps you didn't do an
375open(), or did it in another package.
a0d0e21e
LW
376
377=item Bad free() ignored
378
be771a83 379(S malloc) An internal routine called free() on something that had never
fa816bf3 380been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 381setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 382
9ea8bc6d 383This message can be seen quite often with DB_File on systems with "hard"
6903afa2 384dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 385which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 386
aa689395
PP
387=item Bad hash
388
389(P) One of the internal hash routines was passed a null HV pointer.
390
6df41af2
GS
391=item Badly placed ()'s
392
393(A) You've accidentally run your script through B<csh> instead
394of Perl. Check the #! line, or manually feed your script into
395Perl yourself.
396
a7cb8dae 397=item Bad name after %s
a0d0e21e 398
be771a83
GS
399(F) You started to name a symbol by using a package prefix, and then
400didn't finish the symbol. In particular, you can't interpolate outside
401of quotes, so
a0d0e21e
LW
402
403 $var = 'myvar';
404 $sym = mypack::$var;
405
406is not the same as
407
408 $var = 'myvar';
409 $sym = "mypack::$var";
410
88e1f1a2
JV
411=item Bad plugin affecting keyword '%s'
412
413(F) An extension using the keyword plugin mechanism violated the
414plugin API.
415
4ad56ec9
IZ
416=item Bad realloc() ignored
417
6903afa2
FC
418(S malloc) An internal routine called realloc() on something that
419had never been malloc()ed in the first place. Mandatory, but can
420be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 421
a0d0e21e
LW
422=item Bad symbol for array
423
424(P) An internal request asked to add an array entry to something that
425wasn't a symbol table entry.
426
4df3f177
SP
427=item Bad symbol for dirhandle
428
429(P) An internal request asked to add a dirhandle entry to something
430that wasn't a symbol table entry.
431
a0d0e21e
LW
432=item Bad symbol for filehandle
433
be771a83
GS
434(P) An internal request asked to add a filehandle entry to something
435that wasn't a symbol table entry.
a0d0e21e
LW
436
437=item Bad symbol for hash
438
439(P) An internal request asked to add a hash entry to something that
440wasn't a symbol table entry.
441
34d09196
GS
442=item Bareword found in conditional
443
be771a83
GS
444(W bareword) The compiler found a bareword where it expected a
445conditional, which often indicates that an || or && was parsed as part
446of the last argument of the previous construct, for example:
34d09196
GS
447
448 open FOO || die;
449
be771a83
GS
450It may also indicate a misspelled constant that has been interpreted as
451a bareword:
34d09196
GS
452
453 use constant TYPO => 1;
454 if (TYOP) { print "foo" }
455
456The C<strict> pragma is useful in avoiding such errors.
457
6df41af2
GS
458=item Bareword "%s" not allowed while "strict subs" in use
459
460(F) With "strict subs" in use, a bareword is only allowed as a
be771a83
GS
461subroutine identifier, in curly brackets or to the left of the "=>"
462symbol. Perhaps you need to predeclare a subroutine?
6df41af2
GS
463
464=item Bareword "%s" refers to nonexistent package
465
be771a83
GS
466(W bareword) You used a qualified bareword of the form C<Foo::>, but the
467compiler saw no other uses of that namespace before that point. Perhaps
468you need to predeclare a package?
6df41af2 469
a0d0e21e
LW
470=item BEGIN failed--compilation aborted
471
be771a83
GS
472(F) An untrapped exception was raised while executing a BEGIN
473subroutine. Compilation stops immediately and the interpreter is
474exited.
a0d0e21e 475
68dc0745
PP
476=item BEGIN not safe after errors--compilation aborted
477
478(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
be771a83
GS
479implies a C<BEGIN {}>) after one or more compilation errors had already
480occurred. Since the intended environment for the C<BEGIN {}> could not
481be guaranteed (due to the errors), and since subsequent code likely
482depends on its correct operation, Perl just gave up.
68dc0745 483
c782d7ee 484=item \%d better written as $%d
6df41af2 485
be771a83
GS
486(W syntax) Outside of patterns, backreferences live on as variables.
487The use of backslashes is grandfathered on the right-hand side of a
488substitution, but stylistically it's better to use the variable form
489because other Perl programmers will expect it, and it works better if
490there are more than 9 backreferences.
6df41af2 491
252aa082
JH
492=item Binary number > 0b11111111111111111111111111111111 non-portable
493
e476b1b5 494(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
495(4294967295) and therefore non-portable between systems. See
496L<perlport> for more on portability concerns.
252aa082 497
69282e91 498=item bind() on closed socket %s
a0d0e21e 499
be771a83
GS
500(W closed) You tried to do a bind on a closed socket. Did you forget to
501check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 502
c289d2f7
JH
503=item binmode() on closed filehandle %s
504
505(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 506Check your control flow and number of arguments.
c289d2f7 507
c5a0f51a
JH
508=item Bit vector size > 32 non-portable
509
e476b1b5 510(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 511
043c750c 512=item Bizarre copy of %s
4633a7c4 513
be771a83 514(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 515copiable.
4633a7c4 516
5a25739d
FC
517=item Bizarre SvTYPE [%d]
518
434f489b 519(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
520encountered an invalid data type.
521
f675dbe5
CB
522=item Buffer overflow in prime_env_iter: %s
523
be771a83
GS
524(W internal) A warning peculiar to VMS. While Perl was preparing to
525iterate over %ENV, it encountered a logical name or symbol definition
526which was too long, so it was truncated to the string shown.
f675dbe5 527
a0d0e21e
LW
528=item Callback called exit
529
4929bf7b 530(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
531exited by calling exit.
532
6df41af2 533=item %s() called too early to check prototype
f675dbe5 534
be771a83
GS
535(W prototype) You've called a function that has a prototype before the
536parser saw a definition or declaration for it, and Perl could not check
537that the call conforms to the prototype. You need to either add an
538early prototype declaration for the subroutine in question, or move the
539subroutine definition ahead of the call to get proper prototype
540checking. Alternatively, if you are certain that you're calling the
541function correctly, you may put an ampersand before the name to avoid
542the warning. See L<perlsub>.
f675dbe5 543
56feebad
FC
544=item Calling POSIX::%s() is deprecated
545
546(D deprecated) You called a function whose use is deprecated. See
547the function's name in L<POSIX> for details.
548
0c7df902
JH
549=item Cannot chr %f
550
551(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
552
553=item Cannot compress %f
554
555(F) You tried converting an infinity or not-a-number to an
556unsigned character, which makes no sense.
557
49704364 558=item Cannot compress integer in pack
0258719b
NC
559
560(F) An argument to pack("w",...) was too large to compress. The BER
561compressed integer format can only be used with positive integers, and you
562attempted to compress Infinity or a very large number (> 1e308).
563See L<perlfunc/pack>.
564
49704364 565=item Cannot compress negative numbers in pack
0258719b
NC
566
567(F) An argument to pack("w",...) was negative. The BER compressed integer
568format can only be used with positive integers. See L<perlfunc/pack>.
569
5c1f4d79
NC
570=item Cannot convert a reference to %s to typeglob
571
6903afa2
FC
572(F) You manipulated Perl's symbol table directly, stored a reference
573in it, then tried to access that symbol via conventional Perl syntax.
574The access triggers Perl to autovivify that typeglob, but it there is
575no legal conversion from that type of reference to a typeglob.
5c1f4d79 576
4040665a 577=item Cannot copy to %s
ba2fdce6
NC
578
579(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 580be directly assigned to.
ba2fdce6 581
b5d97229
RGS
582=item Cannot find encoding "%s"
583
584(S io) You tried to apply an encoding that did not exist to a filehandle,
585either with open() or binmode().
586
0c7df902
JH
587=item Cannot pack %f with '%c'
588
589(F) You tried converting an infinity or not-a-number to a character,
590which makes no sense.
591
592=item Cannot printf %f with '%c'
593
594(F) You tried printing an infinity or not-a-number as a character (%c),
595which makes no sense. Maybe you meant '%s', or just stringifying it?
596
7355df7e
FC
597=item Cannot set tied @DB::args
598
599(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
600is not supported. (Before this error was added, it used to crash.)
601
ce65bc73
FC
602=item Cannot tie unreifiable array
603
604(P) You somehow managed to call C<tie> on an array that does not
605keep a reference count on its arguments and cannot be made to
606do so. Such arrays are not even supposed to be accessible to
607Perl code, but are only used internally.
608
96ebfdd7
RK
609=item Can only compress unsigned integers in pack
610
611(F) An argument to pack("w",...) was not an integer. The BER compressed
612integer format can only be used with positive integers, and you attempted
613to compress something else. See L<perlfunc/pack>.
614
a0d0e21e
LW
615=item Can't bless non-reference value
616
617(F) Only hard references may be blessed. This is how Perl "enforces"
618encapsulation of objects. See L<perlobj>.
619
dc57907a
RGS
620=item Can't "break" in a loop topicalizer
621
0d863452 622(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 623a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
624
625=item Can't "break" outside a given block
dc57907a 626
0d863452
RH
627(F) You called C<break>, but you're not inside a C<given> block.
628
6df41af2
GS
629=item Can't call method "%s" on an undefined value
630
631(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
632object reference or package name contains an undefined value. Something
633like this will reproduce the error:
6df41af2
GS
634
635 $BADREF = undef;
636 process $BADREF 1,2,3;
637 $BADREF->process(1,2,3);
638
a0d0e21e
LW
639=item Can't call method "%s" on unblessed reference
640
54310121 641(F) A method call must know in what package it's supposed to run. It
be771a83
GS
642ordinarily finds this out from the object reference you supply, but you
643didn't supply an object reference in this case. A reference isn't an
644object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
645
646=item Can't call method "%s" without a package or object reference
647
648(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
649object reference or package name contains an expression that returns a
650defined value which is neither an object reference nor a package name.
72b5445b
GS
651Something like this will reproduce the error:
652
653 $BADREF = 42;
654 process $BADREF 1,2,3;
655 $BADREF->process(1,2,3);
656
dfe378f1
FC
657=item Can't call mro_isa_changed_in() on anonymous symbol table
658
659(P) Perl got confused as to whether a hash was a plain hash or a
660symbol table hash when trying to update @ISA caches.
661
2bf7e7b2
FC
662=item Can't call mro_method_changed_in() on anonymous symbol table
663
664(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
665not attached to the symbol table.
666
a0d0e21e
LW
667=item Can't chdir to %s
668
f703fc96 669(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
670that you can chdir to, possibly because it doesn't exist.
671
0545a864 672=item Can't check filesystem of script "%s" for nosuid
104d25b7 673
be771a83
GS
674(P) For some reason you can't check the filesystem of the script for
675nosuid.
104d25b7 676
22e74366 677=item Can't coerce %s to %s in %s
a0d0e21e
LW
678
679(F) Certain types of SVs, in particular real symbol table entries
55497cff 680(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
681say things like:
682
683 *foo += 1;
684
685You CAN say
686
687 $foo = *foo;
688 $foo += 1;
689
690but then $foo no longer contains a glob.
691
0d863452 692=item Can't "continue" outside a when block
dc57907a 693
0d863452
RH
694(F) You called C<continue>, but you're not inside a C<when>
695or C<default> block.
696
a0d0e21e
LW
697=item Can't create pipe mailbox
698
be771a83
GS
699(P) An error peculiar to VMS. The process is suffering from exhausted
700quotas or other plumbing problems.
a0d0e21e 701
eb64745e
GS
702=item Can't declare %s in "%s"
703
30c282f6
NC
704(F) Only scalar, array, and hash variables may be declared as "my", "our" or
705"state" variables. They must have ordinary identifiers as names.
a0d0e21e 706
fc7debfb
FC
707=item Can't "default" outside a topicalizer
708
709(F) You have used a C<default> block that is neither inside a
710C<foreach> loop nor a C<given> block. (Note that this error is
711issued on exit from the C<default> block, so you won't get the
712error if you use an explicit C<continue>.)
713
6df41af2
GS
714=item Can't do inplace edit: %s is not a regular file
715
be771a83 716(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 717a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 718
a0d0e21e
LW
719=item Can't do inplace edit on %s: %s
720
be771a83
GS
721(S inplace) The creation of the new file failed for the indicated
722reason.
a0d0e21e 723
54310121 724=item Can't do inplace edit without backup
a0d0e21e 725
be771a83
GS
726(F) You're on a system such as MS-DOS that gets confused if you try
727reading from a deleted (but still opened) file. You have to say
728C<-i.bak>, or some such.
a0d0e21e 729
10f9c03d 730=item Can't do inplace edit: %s would not be unique
a0d0e21e 731
e476b1b5 732(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
733characters and Perl was unable to create a unique filename during
734inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 735
a0d0e21e
LW
736=item Can't do waitpid with flags
737
be771a83
GS
738(F) This machine doesn't have either waitpid() or wait4(), so only
739waitpid() without flags is emulated.
a0d0e21e 740
a0d0e21e
LW
741=item Can't emulate -%s on #! line
742
be771a83
GS
743(F) The #! line specifies a switch that doesn't make sense at this
744point. For example, it'd be kind of silly to put a B<-x> on the #!
745line.
a0d0e21e 746
1109a392
MHM
747=item Can't %s %s-endian %ss on this platform
748
749(F) Your platform's byte-order is neither big-endian nor little-endian,
750or it has a very strange pointer size. Packing and unpacking big- or
751little-endian floating point values and pointers may not be possible.
752See L<perlfunc/pack>.
753
a0d0e21e
LW
754=item Can't exec "%s": %s
755
d1be9408 756(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
757named program for the indicated reason. Typical reasons include: the
758permissions were wrong on the file, the file wasn't found in
759C<$ENV{PATH}>, the executable in question was compiled for another
760architecture, or the #! line in a script points to an interpreter that
761can't be run for similar reasons. (Or maybe your system doesn't support
762#! at all.)
a0d0e21e
LW
763
764=item Can't exec %s
765
be771a83
GS
766(F) Perl was trying to execute the indicated program for you because
767that's what the #! line said. If that's not what you wanted, you may
768need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
769
770=item Can't execute %s
771
be771a83
GS
772(F) You used the B<-S> switch, but the copies of the script to execute
773found in the PATH did not have correct permissions.
2a92aaa0 774
6df41af2 775=item Can't find an opnumber for "%s"
2a92aaa0 776
be771a83
GS
777(F) A string of a form C<CORE::word> was given to prototype(), but there
778is no builtin with the name C<word>.
6df41af2 779
56ca2fc0
JH
780=item Can't find %s character property "%s"
781
782(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 783could not be found. Maybe you misspelled the name of the property?
e1b711da 784See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 785for a complete list of available official properties.
56ca2fc0 786
6df41af2
GS
787=item Can't find label %s
788
be771a83
GS
789(F) You said to goto a label that isn't mentioned anywhere that it's
790possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
791
792=item Can't find %s on PATH
793
be771a83
GS
794(F) You used the B<-S> switch, but the script to execute could not be
795found in the PATH.
a0d0e21e 796
6df41af2 797=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 798
be771a83
GS
799(F) You used the B<-S> switch, but the script to execute could not be
800found in the PATH, or at least not with the correct permissions. The
801script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
802
803=item Can't find string terminator %s anywhere before EOF
804
be771a83
GS
805(F) Perl strings can stretch over multiple lines. This message means
806that the closing delimiter was omitted. Because bracketed quotes count
807nesting levels, the following is missing its final parenthesis:
a0d0e21e 808
fb73857a
PP
809 print q(The character '(' starts a side comment.);
810
97b3d10f 811If you're getting this error from a here-document, you may have
b6b8cb97
FC
812included unseen whitespace before or after your closing tag or there
813may not be a linebreak after it. A good programmer's editor will have
814a way to help you find these characters (or lack of characters). See
815L<perlop> for the full details on here-documents.
a0d0e21e 816
660a4616
ST
817=item Can't find Unicode property definition "%s"
818
5f8ad6b6
FC
819(F) You may have tried to use C<\p> which means a Unicode
820property (for example C<\p{Lu}> matches all uppercase
fa816bf3 821letters). If you did mean to use a Unicode property, see
e1b711da 822L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 823for a complete list of available properties. If you didn't
fa816bf3
FC
824mean to use a Unicode property, escape the C<\p>, either by
825C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 826until C<\E>).
660a4616 827
b3647a36 828=item Can't fork: %s
a0d0e21e 829
be771a83
GS
830(F) A fatal error occurred while trying to fork while opening a
831pipeline.
a0d0e21e 832
b3647a36
SR
833=item Can't fork, trying again in 5 seconds
834
c973c02e 835(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
836after five seconds.
837
748a9306
LW
838=item Can't get filespec - stale stat buffer?
839
be771a83
GS
840(S) A warning peculiar to VMS. This arises because of the difference
841between access checks under VMS and under the Unix model Perl assumes.
842Under VMS, access checks are done by filename, rather than by bits in
843the stat buffer, so that ACLs and other protections can be taken into
844account. Unfortunately, Perl assumes that the stat buffer contains all
845the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 846the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
847the device name and FID present in the stat buffer, but this works only
848if you haven't made a subsequent call to the CRTL stat() routine,
849because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
850appears, the name lookup failed, and the access-checking routine gave up
851and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
852routine knows about the Perl C<stat> operator and file tests, so you
853shouldn't ever see this warning in response to a Perl command; it arises
854only if some internal code takes stat buffers lightly.)
748a9306 855
a0d0e21e
LW
856=item Can't get pipe mailbox device name
857
be771a83
GS
858(P) An error peculiar to VMS. After creating a mailbox to act as a
859pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
860
861=item Can't get SYSGEN parameter value for MAXBUF
862
748a9306
LW
863(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
864mailbox buffers to be, and didn't get an answer.
a0d0e21e 865
6df41af2 866=item Can't "goto" into the middle of a foreach loop
a0d0e21e 867
be771a83
GS
868(F) A "goto" statement was executed to jump into the middle of a foreach
869loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
870
871=item Can't "goto" out of a pseudo block
872
be771a83
GS
873(F) A "goto" statement was executed to jump out of what might look like
874a block, except that it isn't a proper block. This usually occurs if
875you tried to jump out of a sort() block or subroutine, which is a no-no.
876See L<perlfunc/goto>.
a0d0e21e 877
5a25739d
FC
878=item Can't goto subroutine from an eval-%s
879
880(F) The "goto subroutine" call can't be used to jump out of an eval
881"string" or block.
882
9850bf21 883=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 884
9850bf21
RH
885(F) The "goto subroutine" call can't be used to jump out of the
886comparison sub for a sort(), or from a similar callback (such
887as the reduce() function in List::Util).
888
6df41af2
GS
889=item Can't goto subroutine outside a subroutine
890
be771a83
GS
891(F) The deeply magical "goto subroutine" call can only replace one
892subroutine call for another. It can't manufacture one out of whole
893cloth. In general you should be calling it out of only an AUTOLOAD
894routine anyway. See L<perlfunc/goto>.
6df41af2 895
0b5b802d
GS
896=item Can't ignore signal CHLD, forcing to default
897
be771a83
GS
898(W signal) Perl has detected that it is being run with the SIGCHLD
899signal (sometimes known as SIGCLD) disabled. Since disabling this
900signal will interfere with proper determination of exit status of child
901processes, Perl has reset the signal to its default value. This
902situation typically indicates that the parent program under which Perl
903may be running (e.g. cron) is being very careless.
0b5b802d 904
e2c0f81f
DG
905=item Can't kill a non-numeric process ID
906
907(F) Process identifiers must be (signed) integers. It is a fatal error to
908attempt to kill() an undefined, empty-string or otherwise non-numeric
909process identifier.
910
6df41af2 911=item Can't "last" outside a loop block
4633a7c4 912
6df41af2 913(F) A "last" statement was executed to break out of the current block,
be771a83
GS
914except that there's this itty bitty problem called there isn't a current
915block. Note that an "if" or "else" block doesn't count as a "loopish"
916block, as doesn't a block given to sort(), map() or grep(). You can
917usually double the curlies to get the same effect though, because the
918inner curlies will be considered a block that loops once. See
919L<perlfunc/last>.
4633a7c4 920
2c7d6b9c
RGS
921=item Can't linearize anonymous symbol table
922
923(F) Perl tried to calculate the method resolution order (MRO) of a
924package, but failed because the package stash has no name.
925
b8170e59
JB
926=item Can't load '%s' for module %s
927
6903afa2
FC
928(F) The module you tried to load failed to load a dynamic extension.
929This may either mean that you upgraded your version of perl to one
930that is incompatible with your old dynamic extensions (which is known
931to happen between major versions of perl), or (more likely) that your
932dynamic extension was built against an older version of the library
933that is installed on your system. You may need to rebuild your old
934dynamic extensions.
b8170e59 935
748a9306
LW
936=item Can't localize lexical variable %s
937
2ba9eb46 938(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
939lexical variable using "my" or "state". This is not allowed. If you
940want to localize a package variable of the same name, qualify it with
941the package name.
748a9306 942
6df41af2 943=item Can't localize through a reference
4727527e 944
6df41af2
GS
945(F) You said something like C<local $$ref>, which Perl can't currently
946handle, because when it goes to restore the old value of whatever $ref
be771a83 947pointed to after the scope of the local() is finished, it can't be sure
64977eb6 948that $ref will still be a reference.
4727527e 949
ea071790 950=item Can't locate %s
ec889f3a 951
fa816bf3
FC
952(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
953Perl looks for the file in all the locations mentioned in @INC, unless
954the file name included the full path to the file. Perhaps you need
955to set the PERL5LIB or PERL5OPT environment variable to say where the
956extra library is, or maybe the script needs to add the library name
be771a83
GS
957to @INC. Or maybe you just misspelled the name of the file. See
958L<perlfunc/require> and L<lib>.
a0d0e21e 959
6df41af2
GS
960=item Can't locate auto/%s.al in @INC
961
be771a83
GS
962(F) A function (or method) was called in a package which allows
963autoload, but there is no function to autoload. Most probable causes
964are a misprint in a function/method name or a failure to C<AutoSplit>
965the file, say, by doing C<make install>.
6df41af2 966
b8170e59
JB
967=item Can't locate loadable object for module %s in @INC
968
969(F) The module you loaded is trying to load an external library, like
d70d8e57 970for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
971unable to locate this library. See L<DynaLoader>.
972
a0d0e21e
LW
973=item Can't locate object method "%s" via package "%s"
974
975(F) You called a method correctly, and it correctly indicated a package
976functioning as a class, but that package doesn't define that particular
2ba9eb46 977method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 978
8af56b9d
FC
979=item Can't locate object method "%s" via package "%s" (perhaps you forgot
980to load "%s"?)
981
982(F) You called a method on a class that did not exist, and the method
983could not be found in UNIVERSAL. This often means that a method
984requires a package that has not been loaded.
985
a0d0e21e
LW
986=item Can't locate package %s for @%s::ISA
987
be771a83
GS
988(W syntax) The @ISA array contained the name of another package that
989doesn't seem to exist.
a0d0e21e 990
2f7da168
RK
991=item Can't locate PerlIO%s
992
993(F) You tried to use in open() a PerlIO layer that does not exist,
994e.g. open(FH, ">:nosuchlayer", "somefile").
995
f4ad53f4 996=item Can't make list assignment to %ENV on this system
3e3baf6d 997
be771a83
GS
998(F) List assignment to %ENV is not supported on some systems, notably
999VMS.
3e3baf6d 1000
cd40cd58
NC
1001=item Can't make loaded symbols global on this platform while loading %s
1002
ff9c1ae8 1003(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1004that symbols from the stated file are made available globally within the
1005process, but that functionality is not available on this platform. Whilst
1006the module likely will still work, this may prevent the perl interpreter
1007from loading other XS-based extensions which need to link directly to
1008functions defined in the C or XS code in the stated file.
1009
a0d0e21e
LW
1010=item Can't modify %s in %s
1011
be771a83
GS
1012(F) You aren't allowed to assign to the item indicated, or otherwise try
1013to change it, such as with an auto-increment.
a0d0e21e 1014
54310121 1015=item Can't modify nonexistent substring
a0d0e21e
LW
1016
1017(P) The internal routine that does assignment to a substr() was handed
1018a NULL.
1019
6df41af2
GS
1020=item Can't modify non-lvalue subroutine call
1021
1022(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1023such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1024
5f05dabc 1025=item Can't msgrcv to read-only var
a0d0e21e 1026
5f05dabc 1027(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1028buffer.
1029
6df41af2
GS
1030=item Can't "next" outside a loop block
1031
1032(F) A "next" statement was executed to reiterate the current block, but
1033there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1034count as a "loopish" block, as doesn't a block given to sort(), map() or
1035grep(). You can usually double the curlies to get the same effect
1036though, because the inner curlies will be considered a block that loops
1037once. See L<perlfunc/next>.
6df41af2 1038
a0d0e21e
LW
1039=item Can't open %s: %s
1040
c47ff5f1 1041(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1042filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1043switches, or explicitly, failed for the indicated reason. Usually
1044this is because you don't have read permission for a file which
1045you named on the command line.
1046
1047(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1048your operating system's equivalent) could not be opened.
a0d0e21e 1049
9a869a14
RGS
1050=item Can't open a reference
1051
1052(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1053using the 3-arg open() syntax:
9a869a14
RGS
1054
1055 open FH, '>', $ref;
1056
1057but your version of perl is compiled without perlio, and this form of
1058open is not supported.
1059
a0d0e21e
LW
1060=item Can't open bidirectional pipe
1061
be771a83
GS
1062(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1063You can try any of several modules in the Perl library to do this, such
1064as IPC::Open2. Alternately, direct the pipe's output to a file using
1065">", and then read it in under a different file handle.
a0d0e21e 1066
748a9306
LW
1067=item Can't open error file %s as stderr
1068
be771a83
GS
1069(F) An error peculiar to VMS. Perl does its own command line
1070redirection, and couldn't open the file specified after '2>' or '2>>' on
1071the command line for writing.
748a9306
LW
1072
1073=item Can't open input file %s as stdin
1074
be771a83
GS
1075(F) An error peculiar to VMS. Perl does its own command line
1076redirection, and couldn't open the file specified after '<' on the
1077command line for reading.
748a9306
LW
1078
1079=item Can't open output file %s as stdout
1080
be771a83
GS
1081(F) An error peculiar to VMS. Perl does its own command line
1082redirection, and couldn't open the file specified after '>' or '>>' on
1083the command line for writing.
748a9306
LW
1084
1085=item Can't open output pipe (name: %s)
1086
be771a83
GS
1087(P) An error peculiar to VMS. Perl does its own command line
1088redirection, and couldn't open the pipe into which to send data destined
1089for stdout.
748a9306 1090
3b1cf97d 1091=item Can't open perl script "%s": %s
a0d0e21e
LW
1092
1093(F) The script you specified can't be opened for the indicated reason.
1094
fa3aa65a
JC
1095If you're debugging a script that uses #!, and normally relies on the
1096shell's $PATH search, the -S option causes perl to do that search, so
1097you don't have to type the path or C<`which $scriptname`>.
1098
6df41af2
GS
1099=item Can't read CRTL environ
1100
1101(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1102from the CRTL's internal environment array and discovered the array was
1103missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1104or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1105searched.
6df41af2 1106
6df41af2
GS
1107=item Can't "redo" outside a loop block
1108
1109(F) A "redo" statement was executed to restart the current block, but
1110there isn't a current block. Note that an "if" or "else" block doesn't
1111count as a "loopish" block, as doesn't a block given to sort(), map()
1112or grep(). You can usually double the curlies to get the same effect
1113though, because the inner curlies will be considered a block that
1114loops once. See L<perlfunc/redo>.
1115
64977eb6 1116=item Can't remove %s: %s, skipping file
10f9c03d 1117
be771a83
GS
1118(S inplace) You requested an inplace edit without creating a backup
1119file. Perl was unable to remove the original file to replace it with
1120the modified file. The file was left unmodified.
10f9c03d 1121
a0d0e21e
LW
1122=item Can't rename %s to %s: %s, skipping file
1123
e476b1b5 1124(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1125probably because you don't have write permission to the directory.
a0d0e21e 1126
748a9306
LW
1127=item Can't reopen input pipe (name: %s) in binary mode
1128
be771a83
GS
1129(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1130to reopen it to accept binary data. Alas, it failed.
748a9306 1131
4f12ec0e
FC
1132=item Can't reset %ENV on this system
1133
1134(F) You called C<reset('E')> or similar, which tried to reset
1135all variables in the current package beginning with "E". In
1136the main package, that includes %ENV. Resetting %ENV is not
1137supported on some systems, notably VMS.
1138
fe13d51d 1139=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1140
1fa582fa
FC
1141(F)(P) Error resolving overloading specified by a method name (as
1142opposed to a subroutine reference): no such method callable via the
1143package. If the method name is C<???>, this is an internal error.
6df41af2 1144
cd06dffe
GS
1145=item Can't return %s from lvalue subroutine
1146
be771a83
GS
1147(F) Perl detected an attempt to return illegal lvalues (such as
1148temporary or readonly values) from a subroutine used as an lvalue. This
1149is not allowed.
cd06dffe 1150
96ebfdd7
RK
1151=item Can't return outside a subroutine
1152
1153(F) The return statement was executed in mainline code, that is, where
1154there was no subroutine call to return out of. See L<perlsub>.
1155
78f9721b
SM
1156=item Can't return %s to lvalue scalar context
1157
6903afa2
FC
1158(F) You tried to return a complete array or hash from an lvalue
1159subroutine, but you called the subroutine in a way that made Perl
1160think you meant to return only one value. You probably meant to
1161write parentheses around the call to the subroutine, which tell
1162Perl that the call should be in list context.
78f9721b 1163
a0d0e21e
LW
1164=item Can't stat script "%s"
1165
be771a83
GS
1166(P) For some reason you can't fstat() the script even though you have it
1167open already. Bizarre.
a0d0e21e 1168
a0d0e21e
LW
1169=item Can't take log of %g
1170
fb73857a 1171(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1172negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1173standard with Perl, though, if you really want to do that for the
1174negative numbers.
a0d0e21e
LW
1175
1176=item Can't take sqrt of %g
1177
1178(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1179negative number. There's a Math::Complex package that comes standard
1180with Perl, though, if you really want to do that.
a0d0e21e
LW
1181
1182=item Can't undef active subroutine
1183
1184(F) You can't undefine a routine that's currently running. You can,
1185however, redefine it while it's running, and you can even undef the
1186redefined subroutine while the old routine is running. Go figure.
1187
c81225bc 1188=item Can't upgrade %s (%d) to %d
a0d0e21e 1189
be771a83
GS
1190(P) The internal sv_upgrade routine adds "members" to an SV, making it
1191into a more specialized kind of SV. The top several SV types are so
1192specialized, however, that they cannot be interconverted. This message
1193indicates that such a conversion was attempted.
a0d0e21e 1194
6651ba0b
FC
1195=item Can't use '%c' after -mname
1196
1197(F) You tried to call perl with the B<-m> switch, but you put something
1198other than "=" after the module name.
1199
1f1ec7b5
KW
1200=item Can't use a hash as a reference
1201
1202(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1203C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1204<= 5.22.0 used to allow this syntax, but shouldn't
1205have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1206
1207=item Can't use an array as a reference
1208
1209(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1210C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1211used to allow this syntax, but shouldn't have. This
1212was deprecated in perl 5.6.1.
1f1ec7b5 1213
1db89ea5
BS
1214=item Can't use anonymous symbol table for method lookup
1215
e27ad1f2 1216(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1217table that doesn't have a name. Symbol tables can become anonymous
1218for example by undefining stashes: C<undef %Some::Package::>.
1219
96ebfdd7
RK
1220=item Can't use an undefined value as %s reference
1221
1222(F) A value used as either a hard reference or a symbolic reference must
1223be a defined value. This helps to delurk some insidious errors.
1224
6df41af2
GS
1225=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1226
be771a83
GS
1227(F) Only hard references are allowed by "strict refs". Symbolic
1228references are disallowed. See L<perlref>.
6df41af2 1229
90b75b61 1230=item Can't use %! because Errno.pm is not available
1d2dff63 1231
20561843 1232(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1233Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1234provide symbolic names for C<$!> errno values.
1235
1109a392
MHM
1236=item Can't use both '<' and '>' after type '%c' in %s
1237
1238(F) A type cannot be forced to have both big-endian and little-endian
1239byte-order at the same time, so this combination of modifiers is not
1240allowed. See L<perlfunc/pack>.
1241
e35475de
KW
1242=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1243
1244(F) defined() is not useful on arrays because it
1245checks for an undefined I<scalar> value. If you want to see if the
1246array is empty, just use C<if (@array) { # not empty }> for example.
1247
1248=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1249
1250(F) C<defined()> is not usually right on hashes.
1251
1252Although C<defined %hash> is false on a plain not-yet-used hash, it
1253becomes true in several non-obvious circumstances, including iterators,
1254weak references, stash names, even remaining true after C<undef %hash>.
1255These things make C<defined %hash> fairly useless in practice, so it now
1256generates a fatal error.
1257
1258If a check for non-empty is what you wanted then just put it in boolean
1259context (see L<perldata/Scalar values>):
1260
1261 if (%hash) {
1262 # not empty
1263 }
1264
1265If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1266variable exists then that's never really been reliable, and isn't
1267a good way to enquire about the features of a package, or whether
1268it's loaded, etc.
1269
6df41af2
GS
1270=item Can't use %s for loop variable
1271
be771a83
GS
1272(F) Only a simple scalar variable may be used as a loop variable on a
1273foreach.
6df41af2 1274
aab6a793 1275=item Can't use global %s in "%s"
6df41af2 1276
be771a83
GS
1277(F) You tried to declare a magical variable as a lexical variable. This
1278is not allowed, because the magic can be tied to only one location
1279(namely the global variable) and it would be incredibly confusing to
1280have variables in your program that looked like magical variables but
6df41af2
GS
1281weren't.
1282
6d3b25aa
RGS
1283=item Can't use '%c' in a group with different byte-order in %s
1284
1285(F) You attempted to force a different byte-order on a type
1286that is already inside a group with a byte-order modifier.
1287For example you cannot force little-endianness on a type that
1288is inside a big-endian group.
1289
c07a80fd
PP
1290=item Can't use "my %s" in sort comparison
1291
1292(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1293You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1294and the variable had earlier been declared as a lexical variable.
1295Either qualify the sort variable with the package name, or rename the
1296lexical variable.
1297
a0d0e21e
LW
1298=item Can't use %s ref as %s ref
1299
1300(F) You've mixed up your reference types. You have to dereference a
1301reference of the type needed. You can use the ref() function to
1302test the type of the reference, if need be.
1303
748a9306 1304=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1305
5e634d20
FC
1306=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1307
b41bf23f
FC
1308(F) You've told Perl to dereference a string, something which
1309C<use strict> blocks to prevent it happening accidentally. See
1310L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1311in a double-quoted string immediately before interpolating a variable,
1312for example in C<"user @$twitter_id">, which says to treat the contents
1313of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1314symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1315
748a9306
LW
1316=item Can't use subscript on %s
1317
1318(F) The compiler tried to interpret a bracketed expression as a
1319subscript. But to the left of the brackets was an expression that
209e7cf1 1320didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1321
6df41af2
GS
1322=item Can't use \%c to mean $%c in expression
1323
75b44862
GS
1324(W syntax) In an ordinary expression, backslash is a unary operator that
1325creates a reference to its argument. The use of backslash to indicate a
1326backreference to a matched substring is valid only as part of a regular
be771a83
GS
1327expression pattern. Trying to do this in ordinary Perl code produces a
1328value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1329instead.
6df41af2 1330
810b8aa5
GS
1331=item Can't weaken a nonreference
1332
1333(F) You attempted to weaken something that was not a reference. Only
1334references can be weakened.
1335
fc7debfb
FC
1336=item Can't "when" outside a topicalizer
1337
1338(F) You have used a when() block that is neither inside a C<foreach>
1339loop nor a C<given> block. (Note that this error is issued on exit
1340from the C<when> block, so you won't get the error if the match fails,
1341or if you use an explicit C<continue>.)
1342
5f05dabc 1343=item Can't x= to read-only value
a0d0e21e 1344
be771a83
GS
1345(F) You tried to repeat a constant value (often the undefined value)
1346with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1347Perhaps you need to copy the value to a temporary, and repeat that.
1348
a04e6aad 1349=item Character following "\c" must be printable ASCII
f9d13529 1350
7357bd17 1351(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1352
727b6379 1353Note that ASCII characters that don't map to control characters are
7357bd17 1354discouraged, and will generate the warning (when enabled)
727b6379 1355L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1356
f337b084 1357=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1358
1359(W pack) You said
1360
1361 pack("C", $x)
1362
1363where $x is either less than 0 or more than 255; the C<"C"> format is
1364only for encoding native operating system characters (ASCII, EBCDIC,
1365and so on) and not for Unicode characters, so Perl behaved as if you meant
1366
1367 pack("C", $x & 255)
1368
1369If you actually want to pack Unicode codepoints, use the C<"U"> format
1370instead.
1371
f337b084 1372=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1373
1374(W pack) You said
1375
1376 pack("c", $x)
1377
1378where $x is either less than -128 or more than 127; the C<"c"> format
1379is only for encoding native operating system characters (ASCII, EBCDIC,
1380and so on) and not for Unicode characters, so Perl behaved as if you meant
1381
1382 pack("c", $x & 255);
1383
1384If you actually want to pack Unicode codepoints, use the C<"U"> format
1385instead.
1386
f337b084
TH
1387=item Character in '%c' format wrapped in unpack
1388
1389(W unpack) You tried something like
1390
1391 unpack("H", "\x{2a1}")
1392
1a147d38 1393where the format expects to process a byte (a character with a value
6903afa2
FC
1394below 256), but a higher value was provided instead. Perl uses the
1395value modulus 256 instead, as if you had provided:
f337b084
TH
1396
1397 unpack("H", "\x{a1}")
1398
5a25739d
FC
1399=item Character in 'W' format wrapped in pack
1400
1401(W pack) You said
1402
1403 pack("U0W", $x)
1404
1405where $x is either less than 0 or more than 255. However, C<U0>-mode
1406expects all values to fall in the interval [0, 255], so Perl behaved
1407as if you meant:
1408
1409 pack("U0W", $x & 255)
1410
f337b084
TH
1411=item Character(s) in '%c' format wrapped in pack
1412
1413(W pack) You tried something like
1414
1415 pack("u", "\x{1f3}b")
1416
1a147d38 1417where the format expects to process a sequence of bytes (character with a
6903afa2 1418value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1419uses the character values modulus 256 instead, as if you had provided:
1420
1421 pack("u", "\x{f3}b")
1422
1423=item Character(s) in '%c' format wrapped in unpack
1424
1425(W unpack) You tried something like
1426
1427 unpack("s", "\x{1f3}b")
1428
1a147d38 1429where the format expects to process a sequence of bytes (character with a
6903afa2 1430value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1431uses the character values modulus 256 instead, as if you had provided:
1432
1433 unpack("s", "\x{f3}b")
1434
f51551f7
FC
1435=item charnames alias definitions may not contain a sequence of multiple spaces
1436
1437(F) You defined a character name which had multiple space characters
1438in a row. Change them to single spaces. Usually these names are
1439defined in the C<:alias> import argument to C<use charnames>, but they
1440could be defined by a translator installed into C<$^H{charnames}>. See
1441L<charnames/CUSTOM ALIASES>.
1442
1443=item charnames alias definitions may not contain trailing white-space
1444
1445(F) You defined a character name which ended in a space
1446character. Remove the trailing space(s). Usually these names are
1447defined in the C<:alias> import argument to C<use charnames>, but they
1448could be defined by a translator installed into C<$^H{charnames}>.
1449See L<charnames/CUSTOM ALIASES>.
1450
1451=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1452
1453(D deprecated, regexp) The \C character class is deprecated, and will
1454become a compile-time error in a future release of perl (tentatively
1455v5.24). This construct allows you to match a single byte of what makes up
1456a multi-byte single UTF8 character, and breaks encapsulation. It is
1457currently also very buggy. If you really need to process the individual
1458bytes, you probably want to convert your string to one where each
1459underlying byte is stored as a character, with utf8::encode().
1460
f866a7cd
FC
1461=item "\c%c" is more clearly written simply as "%s"
1462
1463(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1464non-printable characters. You used it for a printable one, which
1465is better written as simply itself, perhaps preceded by a backslash
1466for non-word characters. Doing it the way you did is not portable
1467between ASCII and EBCDIC platforms.
f866a7cd 1468
6651ba0b
FC
1469=item Cloning substitution context is unimplemented
1470
1471(F) Creating a new thread inside the C<s///> operator is not supported.
1472
abc7ecad
SP
1473=item closedir() attempted on invalid dirhandle %s
1474
1475(W io) The dirhandle you tried to close is either closed or not really
1476a dirhandle. Check your control flow.
1477
5a25739d
FC
1478=item close() on unopened filehandle %s
1479
1480(W unopened) You tried to close a filehandle that was never opened.
1481
541ed3a9
FC
1482=item Closure prototype called
1483
1484(F) If a closure has attributes, the subroutine passed to an attribute
1485handler is the prototype that is cloned when a new closure is created.
1486This subroutine cannot be called.
1487
49704364
LW
1488=item Code missing after '/'
1489
6903afa2
FC
1490(F) You had a (sub-)template that ends with a '/'. There must be
1491another template code following the slash. See L<perlfunc/pack>.
49704364 1492
5a25739d
FC
1493=item Code point 0x%X is not Unicode, may not be portable
1494
2d88a86a 1495(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1496of U+10FFFF.
1497
1498Perl allows strings to contain a superset of Unicode code points, up
1499to the limit of what is storable in an unsigned integer on your system,
1500but these may not be accepted by other languages/systems. At one time,
1501it was legal in some standards to have code points up to 0x7FFF_FFFF,
1502but not higher. Code points above 0xFFFF_FFFF require larger than a
150332 bit word.
0876b9a0 1504
6df41af2
GS
1505=item %s: Command not found
1506
a892b81a 1507(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1508instead of Perl. Check the #! line, or manually feed your script into
1509Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1510
1511 #!/usr/bin/perl -w
6df41af2 1512
7a2e2cd6
PP
1513=item Compilation failed in require
1514
1515(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1516Perl uses this generic message when none of the errors that it
1517encountered were severe enough to halt compilation immediately.
7a2e2cd6 1518
c3464db5
DD
1519=item Complex regular subexpression recursion limit (%d) exceeded
1520
be771a83
GS
1521(W regexp) The regular expression engine uses recursion in complex
1522situations where back-tracking is required. Recursion depth is limited
1523to 32766, or perhaps less in architectures where the stack cannot grow
1524arbitrarily. ("Simple" and "medium" situations are handled without
1525recursion and are not subject to a limit.) Try shortening the string
1526under examination; looping in Perl code (e.g. with C<while>) rather than
1527in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1528that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1529on I<Mastering Regular Expressions>.)
c3464db5 1530
69282e91 1531=item connect() on closed socket %s
a0d0e21e 1532
be771a83
GS
1533(W closed) You tried to do a connect on a closed socket. Did you forget
1534to check the return value of your socket() call? See
1535L<perlfunc/connect>.
a0d0e21e 1536
e21e7c6a
FC
1537=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1538
1539(F) The subroutine registered to handle constant overloading
1540(see L<overload>) or a custom charnames handler (see
1541L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1542
1543=item Constant(%s): $^H{%s} is not defined
1544
1545(F) The parser found inconsistencies while attempting to define an
1546overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1547L<overload> pragma?
e21e7c6a 1548
779c5bc9
GS
1549=item Constant is not %s reference
1550
1551(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1552is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1553The message indicates the type of reference that was expected. This
be771a83 1554usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1555See L<perlsub/"Constant Functions"> and L<constant>.
1556
4cee8e80
CS
1557=item Constant subroutine %s redefined
1558
aeb94125
FC
1559(W redefine)(S) You redefined a subroutine which had previously
1560been eligible for inlining. See L<perlsub/"Constant Functions">
1561for commentary and workarounds.
4cee8e80 1562
9607fc9c
PP
1563=item Constant subroutine %s undefined
1564
be771a83
GS
1565(W misc) You undefined a subroutine which had previously been eligible
1566for inlining. See L<perlsub/"Constant Functions"> for commentary and
1567workarounds.
9607fc9c 1568
5a25739d
FC
1569=item Constant(%s) unknown
1570
1571(F) The parser found inconsistencies either while attempting
1572to define an overloaded constant, or when trying to find the
1573character name specified in the C<\N{...}> escape. Perhaps you
1574forgot to load the corresponding L<overload> pragma?.
1575
e7ea3e70
IZ
1576=item Copy method did not return a reference
1577
6903afa2 1578(F) The method which overloads "=" is buggy. See
13a2d996 1579L<overload/Copy Constructor>.
e7ea3e70 1580
4aaa4757
FC
1581=item &CORE::%s cannot be called directly
1582
1583(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1584with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1585in this package cannot yet be called that way, but must be
1586called as barewords. Something like this will work:
1587
1588 BEGIN { *shove = \&CORE::push; }
1589 shove @array, 1,2,3; # pushes on to @array
1590
6798c92b
GS
1591=item CORE::%s is not a keyword
1592
1593(F) The CORE:: namespace is reserved for Perl keywords.
1594
675fa9ff
FC
1595=item Corrupted regexp opcode %d > %d
1596
1597(P) This is either an error in Perl, or, if you're using
1598one, your L<custom regular expression engine|perlreapi>. If not the
1599latter, report the problem through the L<perlbug> utility.
1600
a0d0e21e
LW
1601=item corrupted regexp pointers
1602
1603(P) The regular expression engine got confused by what the regular
1604expression compiler gave it.
1605
1606=item corrupted regexp program
1607
be771a83
GS
1608(P) The regular expression engine got passed a regexp program without a
1609valid magic number.
a0d0e21e 1610
de42a5a9 1611=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1612
1613(P) The malloc package that comes with Perl had an internal failure.
1614
49704364
LW
1615=item Count after length/code in unpack
1616
1617(F) You had an unpack template indicating a counted-length string, but
1618you have also specified an explicit size for the string. See
1619L<perlfunc/pack>.
1620
f2cccb4c
KW
1621=for comment
1622The following are used in lib/diagnostics.t for testing two =items that
1623share the same description. Changes here need to be propagated to there
1624
6651ba0b
FC
1625=item Deep recursion on anonymous subroutine
1626
a0d0e21e
LW
1627=item Deep recursion on subroutine "%s"
1628
be771a83
GS
1629(W recursion) This subroutine has called itself (directly or indirectly)
1630100 times more than it has returned. This probably indicates an
1631infinite recursion, unless you're writing strange benchmark programs, in
1632which case it indicates something else.
a0d0e21e 1633
aad1d01f
NC
1634This threshold can be changed from 100, by recompiling the F<perl> binary,
1635setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1636
e0e4a6e3
FC
1637=item (?(DEFINE)....) does not allow branches in regex; marked by
1638S<<-- HERE> in m/%s/
bcb95744 1639
6903afa2 1640(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1641most likely cause of this error is that you left out a parenthesis inside
1642of the C<....> part.
1643
9e3ec65c 1644The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1645discovered.
1646
62658f4d
PM
1647=item %s defines neither package nor VERSION--version check failed
1648
1649(F) You said something like "use Module 42" but in the Module file
1650there are neither package declarations nor a C<$VERSION>.
1651
36447869
FC
1652=item delete argument is index/value array slice, use array slice
1653
1654(F) You used index/value array slice syntax (C<%array[...]>) as
1655the argument to C<delete>. You probably meant C<@array[...]> with
1656an @ symbol instead.
1657
1658=item delete argument is key/value hash slice, use hash slice
1659
1660(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1661C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1662
0ffcbc25
FC
1663=item delete argument is not a HASH or ARRAY element or slice
1664
4a0af295 1665(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1666such as:
1667
1668 $foo{$bar}
1669 $ref->{"susie"}[12]
1670
1671or a hash or array slice, such as:
1672
1673 @foo[$bar, $baz, $xyzzy]
1674 @{$ref->[12]}{"susie", "queue"}
1675
fc36a67e
PP
1676=item Delimiter for here document is too long
1677
be771a83
GS
1678(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1679long for Perl to handle. You have to be seriously twisted to write code
1680that triggers this error.
fc36a67e 1681
6d3b25aa
RGS
1682=item Deprecated use of my() in false conditional
1683
fa816bf3
FC
1684(D deprecated) You used a declaration similar to C<my $x if 0>. There
1685has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1686not to be cleared at scope exit when its declaration includes a false
6903afa2 1687conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1688static variable. Since we intend to fix this bug, we don't want people
6903afa2 1689relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1690declaring the variable in a separate block outside the function, eg
36fb85f3 1691
6d3b25aa
RGS
1692 sub f { my $x if 0; return $x++ }
1693
1694becomes
1695
1696 { my $x; sub f { return $x++ } }
1697
ea9d9ebc 1698Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1699lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1700
1701 sub f { state $x; return $x++ }
1702
500ab966
RGS
1703=item DESTROY created new reference to dead object '%s'
1704
1705(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1706just being DESTROYed. Perl is confused, and prefers to abort rather
1707than to create a dangling reference.
500ab966 1708
3cdd684c
TP
1709=item Did not produce a valid header
1710
1711See Server error.
1712
6df41af2
GS
1713=item %s did not return a true value
1714
1715(F) A required (or used) file must return a true value to indicate that
1716it compiled correctly and ran its initialization code correctly. It's
1717traditional to end such a file with a "1;", though any true value would
1718do. See L<perlfunc/require>.
1719
cc507455 1720=item (Did you mean &%s instead?)
4633a7c4 1721
413ff9f6
FC
1722(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1723some such.
4633a7c4 1724
cc507455 1725=item (Did you mean "local" instead of "our"?)
33633739 1726
be771a83
GS
1727(W misc) Remember that "our" does not localize the declared global
1728variable. You have declared it again in the same lexical scope, which
1729seems superfluous.
33633739 1730
cc507455 1731=item (Did you mean $ or @ instead of %?)
a0d0e21e 1732
be771a83
GS
1733(W) You probably said %hash{$key} when you meant $hash{$key} or
1734@hash{@keys}. On the other hand, maybe you just meant %hash and got
1735carried away.
748a9306 1736
7e1af8bc 1737=item Died
5f05dabc
PP
1738
1739(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1740you called it with no args and C<$@> was empty.
5f05dabc 1741
3cdd684c
TP
1742=item Document contains no data
1743
1744See Server error.
1745
62658f4d
PM
1746=item %s does not define %s::VERSION--version check failed
1747
1748(F) You said something like "use Module 42" but the Module did not
943fc58e 1749define a C<$VERSION>.
62658f4d 1750
49704364
LW
1751=item '/' does not take a repeat count
1752
1753(F) You cannot put a repeat count of any kind right after the '/' code.
1754See L<perlfunc/pack>.
1755
95cb0d72
FC
1756=item Don't know how to get file name
1757
1758(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1759somehow called on another platform. This should not happen.
1760
4021c788 1761=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1762
1763(P) The internal handling of magical variables has been cursed.
1764
1765=item do_study: out of memory
1766
1767(P) This should have been caught by safemalloc() instead.
1768
6df41af2
GS
1769=item (Do you need to predeclare %s?)
1770
56da5a46
RGS
1771(S syntax) This is an educated guess made in conjunction with the message
1772"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1773name is being referenced that hasn't been declared yet. This may be
1774because of ordering problems in your file, or because of a missing
be771a83
GS
1775"sub", "package", "require", or "use" statement. If you're referencing
1776something that isn't defined yet, you don't actually have to define the
1777subroutine or package before the current location. You can use an empty
1778"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1779
ac206dc8
RGS
1780=item dump() better written as CORE::dump()
1781
1782(W misc) You used the obsolescent C<dump()> built-in function, without fully
1783qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1784
84d78eb7
YO
1785=item dump is not supported
1786
1787(F) Your machine doesn't support dump/undump.
1788
a0d0e21e
LW
1789=item Duplicate free() ignored
1790
be771a83
GS
1791(S malloc) An internal routine called free() on something that had
1792already been freed.
a0d0e21e 1793
1109a392
MHM
1794=item Duplicate modifier '%c' after '%c' in %s
1795
35f0cd76
FC
1796(W unpack) You have applied the same modifier more than once after a
1797type in a pack template. See L<perlfunc/pack>.
1109a392 1798
0953b66b
FC
1799=item each on reference is experimental
1800
0773cb3e
FC
1801(S experimental::autoderef) C<each> with a scalar argument is experimental
1802and may change or be removed in a future Perl version. If you want to
1803take the risk of using this feature, simply disable this warning:
0953b66b 1804
d401967c 1805 no warnings "experimental::autoderef";
0953b66b 1806
4633a7c4
LW
1807=item elseif should be elsif
1808
fa816bf3
FC
1809(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1810it's ugly. Your code will be interpreted as an attempt to call a method
1811named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1812unlikely to be what you want.
1813
e0e4a6e3 1814=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1815
af6f566e 1816(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1817described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1818a regular expression without specifying the property name.
ab13f0c7 1819
85ab1d1d 1820=item entering effective %s failed
5ff3f7a4 1821
85ab1d1d 1822(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1823effective uids or gids failed.
1824
c038024b
RGS
1825=item %ENV is aliased to %s
1826
1827(F) You're running under taint mode, and the C<%ENV> variable has been
1828aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1829program's environment. This is potentially insecure.
c038024b 1830
748a9306
LW
1831=item Error converting file specification %s
1832
5f05dabc 1833(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1834specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1835single form when it must operate on them directly. Either you've passed
1836an invalid file specification to Perl, or you've found a case the
1837conversion routines don't handle. Drat.
748a9306 1838
ad19ef22 1839=item Eval-group in insecure regular expression
e4d48cc9 1840
be771a83
GS
1841(F) Perl detected tainted data when trying to compile a regular
1842expression that contains the C<(?{ ... })> zero-width assertion, which
1843is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1844
ad19ef22 1845=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1846
be771a83
GS
1847(F) Perl tried to compile a regular expression containing the
1848C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1849pattern contains interpolated values. Since that is a security risk,
1850it is not allowed. If you insist, you may still do this by using the
1851C<re 'eval'> pragma or by explicitly building the pattern from an
1852interpolated string at run time and using that in an eval(). See
1853L<perlre/(?{ code })>.
e4d48cc9 1854
ad19ef22 1855=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1856
be771a83
GS
1857(F) A regular expression contained the C<(?{ ... })> zero-width
1858assertion, but that construct is only allowed when the C<use re 'eval'>
1859pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1860
e0e4a6e3
FC
1861=item EVAL without pos change exceeded limit in regex; marked by
1862S<<-- HERE> in m/%s/
1a147d38
YO
1863
1864(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1865any text. Restructure the pattern so that text is consumed.
1a147d38 1866
9e3ec65c 1867The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1868discovered.
1869
fc36a67e
PP
1870=item Excessively long <> operator
1871
1872(F) The contents of a <> operator may not exceed the maximum size of a
1873Perl identifier. If you're just trying to glob a long list of
1874filenames, try using the glob() operator, or put the filenames into a
1875variable and glob that.
1876
ed9aa3b7
SG
1877=item exec? I'm not *that* kind of operating system
1878
af8bb25a 1879(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1880OS. See L<perlport>.
ed9aa3b7 1881
fe13d51d 1882=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1883
1884(F) The final summary message when a Perl compilation fails.
1885
0ffcbc25
FC
1886=item exists argument is not a HASH or ARRAY element or a subroutine
1887
4a0af295 1888(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1889subroutine with an ampersand, such as:
1890
1891 $foo{$bar}
1892 $ref->{"susie"}[12]
1893 &do_something
1894
1895=item exists argument is not a subroutine name
1896
ccfc2567
FC
1897(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1898and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1899
a0d0e21e
LW
1900=item Exiting eval via %s
1901
be771a83
GS
1902(W exiting) You are exiting an eval by unconventional means, such as a
1903goto, or a loop control statement.
e476b1b5
GS
1904
1905=item Exiting format via %s
1906
9a2ff54b 1907(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1908goto, or a loop control statement.
a0d0e21e 1909
0a753a76
PP
1910=item Exiting pseudo-block via %s
1911
be771a83
GS
1912(W exiting) You are exiting a rather special block construct (like a
1913sort block or subroutine) by unconventional means, such as a goto, or a
1914loop control statement. See L<perlfunc/sort>.
0a753a76 1915
a0d0e21e
LW
1916=item Exiting subroutine via %s
1917
be771a83
GS
1918(W exiting) You are exiting a subroutine by unconventional means, such
1919as a goto, or a loop control statement.
a0d0e21e
LW
1920
1921=item Exiting substitution via %s
1922
be771a83
GS
1923(W exiting) You are exiting a substitution by unconventional means, such
1924as a return, a goto, or a loop control statement.
a0d0e21e 1925
e0e4a6e3 1926=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1927
675fa9ff 1928(F) You wrote something like
c608e803
KW
1929
1930 (?13
1931
1932to denote a capturing group of the form
1933L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1934but omitted the C<")">.
1935
e0e4a6e3 1936=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1937
8b6fbf55
FC
1938(F) The C<(?[...])> extended character class regular expression construct
1939only allows character classes (including character class escapes like
1940C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1941containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1942This allows a regular expression containing just C<(?[...])> to be
1943interpolated. If you see this error message, then you probably
1944have some other C<(?...)> construct inside your character class. See
1945L<perlrecharclass/Extended Bracketed Character Classes>.
1946
30d9c59b
Z
1947=item Experimental subroutine signatures not enabled
1948
1949(F) To use subroutine signatures, you must first enable them:
1950
caa35032 1951 no warnings "experimental::signatures";
30d9c59b
Z
1952 use feature "signatures";
1953 sub foo ($left, $right) { ... }
1954
6da34ecb
FC
1955=item Experimental "%s" subs not enabled
1956
1957(F) To use lexical subs, you must first enable them:
1958
1959 no warnings 'experimental::lexical_subs';
1960 use feature 'lexical_subs';
1961 my sub foo { ... }
1962
7b8d334a
GS
1963=item Explicit blessing to '' (assuming package main)
1964
be771a83
GS
1965(W misc) You are blessing a reference to a zero length string. This has
1966the effect of blessing the reference into the package main. This is
1967usually not what you want. Consider providing a default target package,
1968e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1969
6df41af2
GS
1970=item %s: Expression syntax
1971
be771a83
GS
1972(A) You've accidentally run your script through B<csh> instead of Perl.
1973Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1974
1975=item %s failed--call queue aborted
1976
3c10abe3
AG
1977(F) An untrapped exception was raised while executing a UNITCHECK,
1978CHECK, INIT, or END subroutine. Processing of the remainder of the
1979queue of such routines has been prematurely ended.
6df41af2 1980
e0e4a6e3 1981=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1982
98d31c73 1983(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1984character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1985in your false range is interpreted as a literal "-". In a C<(?[...])>
1986construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1987the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1988the problem was discovered. See L<perlre>.
73b437c8 1989
1b1ee2ef 1990=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1991
be771a83
GS
1992(P) An error peculiar to VMS. Something untoward happened in a VMS
1993system service or RTL routine; Perl's exit status should provide more
1994details. The filename in "at %s" and the line number in "line %d" tell
1995you which section of the Perl source code is distressed.
a0d0e21e
LW
1996
1997=item fcntl is not implemented
1998
1999(F) Your machine apparently doesn't implement fcntl(). What is this, a
2000PDP-11 or something?
2001
22846ab4
AB
2002=item FETCHSIZE returned a negative value
2003
2004(F) A tied array claimed to have a negative number of elements, which
2005is not possible.
2006
f337b084
TH
2007=item Field too wide in 'u' format in pack
2008
d8b5cc61 2009(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2010which can't encode values above 63. So there is no point in asking for
2011a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2012C<u63> as the format.
f337b084 2013
af8c498a 2014=item Filehandle %s opened only for input
a0d0e21e 2015
6c8d78fb
HS
2016(W io) You tried to write on a read-only filehandle. If you intended
2017it to be a read-write filehandle, you needed to open it with "+<" or
2018"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2019write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2020
af8c498a 2021=item Filehandle %s opened only for output
a0d0e21e 2022
6c8d78fb
HS
2023(W io) You tried to read from a filehandle opened only for writing, If
2024you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2025with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2026read from the file, use "<". See L<perlfunc/open>. Another possibility
2027is that you attempted to open filedescriptor 0 (also known as STDIN) for
2028output (maybe you closed STDIN earlier?).
97828cef
RGS
2029
2030=item Filehandle %s reopened as %s only for input
2031
2032(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2033as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2034previously.
2035
2036=item Filehandle STDIN reopened as %s only for output
2037
2038(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2039as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2040
2041=item Final $ should be \$ or $name
2042
2043(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2044a literal dollar sign, or was meant to introduce a variable name that
2045happens to be missing. So you have to put either the backslash or the
2046name.
a0d0e21e 2047
56e90b21
GS
2048=item flock() on closed filehandle %s
2049
be771a83 2050(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2051some time before now. Check your control flow. flock() operates on
be771a83
GS
2052filehandles. Are you attempting to call flock() on a dirhandle by the
2053same name?
56e90b21 2054
6df41af2
GS
2055=item Format not terminated
2056
2057(F) A format must be terminated by a line with a solitary dot. Perl got
2058to the end of your file without finding such a line.
2059
a0d0e21e
LW
2060=item Format %s redefined
2061
e476b1b5 2062(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2063
2064 {
271595cc 2065 no warnings 'redefine';
a0d0e21e
LW
2066 eval "format NAME =...";
2067 }
2068
a0d0e21e
LW
2069=item Found = in conditional, should be ==
2070
e476b1b5 2071(W syntax) You said
a0d0e21e
LW
2072
2073 if ($foo = 123)
2074
2075when you meant
2076
2077 if ($foo == 123)
2078
2079(or something like that).
2080
6df41af2
GS
2081=item %s found where operator expected
2082
56da5a46
RGS
2083(S syntax) The Perl lexer knows whether to expect a term or an operator.
2084If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2085operator, it gives you this warning. Usually it indicates that an
2086operator or delimiter was omitted, such as a semicolon.
6df41af2 2087
a0d0e21e
LW
2088=item gdbm store returned %d, errno %d, key "%s"
2089
2090(S) A warning from the GDBM_File extension that a store failed.
2091
2092=item gethostent not implemented
2093
2094(F) Your C library apparently doesn't implement gethostent(), probably
2095because if it did, it'd feel morally obligated to return every hostname
2096on the Internet.
2097
69282e91 2098=item get%sname() on closed socket %s
a0d0e21e 2099
be771a83
GS
2100(W closed) You tried to get a socket or peer socket name on a closed
2101socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2102
748a9306
LW
2103=item getpwnam returned invalid UIC %#o for user "%s"
2104
2105(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2106C<getpwnam> operator returned an invalid UIC.
2107
6df41af2
GS
2108=item getsockopt() on closed socket %s
2109
be771a83
GS
2110(W closed) You tried to get a socket option on a closed socket. Did you
2111forget to check the return value of your socket() call? See
6df41af2
GS
2112L<perlfunc/getsockopt>.
2113
0f539b13
BF
2114=item given is experimental
2115
675fa9ff
FC
2116(S experimental::smartmatch) C<given> depends on smartmatch, which
2117is experimental, so its behavior may change or even be removed
2118in any future release of perl. See the explanation under
2119L<perlsyn/Experimental Details on given and when>.
0f539b13 2120
68567d27
FC
2121=item Global symbol "%s" requires explicit package name (did you forget to
2122declare "my %s"?)
6df41af2 2123
a4edf47d 2124(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2125that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2126declared beforehand using "our", or explicitly qualified to say
2127which package the global variable is in (using "::").
6df41af2 2128
e476b1b5
GS
2129=item glob failed (%s)
2130
5ead438e 2131(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2132for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2133pattern that caused the external program to fail and exit with a
be771a83 2134nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2135resulted in a coredump, this may also mean that your csh (C shell)
2136is broken. If so, you should change all of the csh-related variables
2137in config.sh: If you have tcsh, make the variables refer to it as
2138if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2139all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2140think csh is missing. In either case, after editing config.sh, run
75b44862 2141C<./Configure -S> and rebuild Perl.
e476b1b5 2142
a0d0e21e
LW
2143=item Glob not terminated
2144
2145(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2146a term, so it's looking for the corresponding right angle bracket, and
2147not finding it. Chances are you left some needed parentheses out
2148earlier in the line, and you really meant a "less than".
a0d0e21e 2149
b35b96b6
JH
2150=item gmtime(%f) failed
2151
2152(W overflow) You called C<gmtime> with a number that it could not handle:
2153too large, too small, or NaN. The returned value is C<undef>.
2154
bcd05b94 2155=item gmtime(%f) too large
8b56d6ff 2156
e9200be3 2157(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2158it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2159date. This warning is also triggered with NaN (the special
fc003d4b
MS
2160not-a-number value).
2161
bcd05b94 2162=item gmtime(%f) too small
fc003d4b 2163
e9200be3 2164(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2165it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2166
6df41af2 2167=item Got an error from DosAllocMem
a0d0e21e 2168
6df41af2
GS
2169(P) An error peculiar to OS/2. Most probably you're using an obsolete
2170version of Perl, and this should not happen anyway.
a0d0e21e
LW
2171
2172=item goto must have label
2173
2174(F) Unlike with "next" or "last", you're not allowed to goto an
2175unspecified destination. See L<perlfunc/goto>.
2176
6651ba0b
FC
2177=item Goto undefined subroutine%s
2178
2179(F) You tried to call a subroutine with C<goto &sub> syntax, but
2180the indicated subroutine hasn't been defined, or if it was, it
2181has since been undefined.
2182
6fbc9859 2183=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2184S<<-- HERE> in m/%s/
1f4f6bf1
YO
2185
2186(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2187they must start with a non-digit word character. A common cause of
2188this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2189
5a25739d
FC
2190=item ()-group starts with a count
2191
2192(F) A ()-group started with a count. A count is supposed to follow
2193something: a template character or a ()-group. See L<perlfunc/pack>.
2194
fe13d51d 2195=item %s had compilation errors.
6df41af2
GS
2196
2197(F) The final summary message when a C<perl -c> fails.
2198
a0d0e21e
LW
2199=item Had to create %s unexpectedly
2200
be771a83
GS
2201(S internal) A routine asked for a symbol from a symbol table that ought
2202to have existed already, but for some reason it didn't, and had to be
2203created on an emergency basis to prevent a core dump.
a0d0e21e 2204
6df41af2
GS
2205=item %s has too many errors
2206
2207(F) The parser has given up trying to parse the program after 10 errors.
2208Further error messages would likely be uninformative.
2209
61e61fbc
JH
2210=item Hexadecimal float: exponent overflow
2211
d8f2b442 2212(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2213than the floating point supports.
2214
2215=item Hexadecimal float: exponent underflow
2216
d8f2b442 2217(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2218than the floating point supports.
2219
cf4f6003
JH
2220=item Hexadecimal float: internal error
2221
2222(F) Something went horribly bad in hexadecimal float handling.
2223
61e61fbc
JH
2224=item Hexadecimal float: mantissa overflow
2225
2226(W overflow) The hexadecimal floating point literal had more bits in
2227the mantissa (the part between the 0x and the exponent, also known as
2228the fraction or the significand) than the floating point supports.
2229
40bca5ae
JH
2230=item Hexadecimal float: precision loss
2231
2232(W overflow) The hexadecimal floating point had internally more
2233digits than could be output. This can be caused by unsupported
2234long double formats, or by 64-bit integers not being available
2235(needed to retrieve the digits under some configurations).
2236
2237=item Hexadecimal float: unsupported long double format
2238
2239(F) You have configured Perl to use long doubles but
d8f2b442 2240the internals of the long double format are unknown;
40bca5ae
JH
2241therefore the hexadecimal float output is impossible.
2242
252aa082
JH
2243=item Hexadecimal number > 0xffffffff non-portable
2244
e476b1b5 2245(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2246(4294967295) and therefore non-portable between systems. See
2247L<perlport> for more on portability concerns.
252aa082 2248
8903cb82
PP
2249=item Identifier too long
2250
2251(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2252about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2253names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2254of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2255
e0e4a6e3
FC
2256=item Ignoring zero length \N{} in character class in regex; marked by
2257S<<-- HERE> in m/%s/
fc8cd66c 2258
f3ba6905 2259(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2260zero-length sequence. When such an escape is used in a character class
2261its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2262been used, and the correct charname handler is in scope.
2263
6df41af2 2264=item Illegal binary digit %s
f675dbe5 2265
6df41af2 2266(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2267
6df41af2 2268=item Illegal binary digit %s ignored
a0d0e21e 2269
be771a83
GS
2270(W digit) You may have tried to use a digit other than 0 or 1 in a
2271binary number. Interpretation of the binary number stopped before the
2272offending digit.
a0d0e21e 2273
6597eb22
FC
2274=item Illegal character after '_' in prototype for %s : %s
2275
e4d150f1
FC
2276(W illegalproto) An illegal character was found in a prototype
2277declaration. The '_' in a prototype must be followed by a ';',
2278indicating the rest of the parameters are optional, or one of '@'
2279or '%', since those two will accept 0 or more final parameters.
6597eb22 2280
78d0fecf 2281=item Illegal character \%o (carriage return)
4fdae800 2282
d5898338 2283(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2284would any other whitespace, which means you should never see this error
2285when Perl was built using standard options. For some reason, your
2286version of Perl appears to have been built without this support. Talk
2287to your Perl administrator.
4fdae800 2288
d37a9538
ST
2289=item Illegal character in prototype for %s : %s
2290
197afce1 2291(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2292Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2293Perhaps you were trying to write a subroutine signature but didn't enable
2294that feature first (C<use feature 'signatures'>), so your signature was
2295instead interpreted as a bad prototype.
d37a9538 2296
904d85c5
RGS
2297=item Illegal declaration of anonymous subroutine
2298
2299(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2300you must always specify a block of code. See L<perlsub>.
904d85c5 2301
8e742a20
MHM
2302=item Illegal declaration of subroutine %s
2303
6903afa2 2304(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2305
a0d0e21e
LW
2306=item Illegal division by zero
2307
be771a83
GS
2308(F) You tried to divide a number by 0. Either something was wrong in
2309your logic, or you need to put a conditional in to guard against
2310meaningless input.
a0d0e21e 2311
6df41af2
GS
2312=item Illegal hexadecimal digit %s ignored
2313
be771a83
GS
2314(W digit) You may have tried to use a character other than 0 - 9 or
2315A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2316number stopped before the illegal character.
6df41af2 2317
a0d0e21e
LW
2318=item Illegal modulus zero
2319
be771a83
GS
2320(F) You tried to divide a number by 0 to get the remainder. Most
2321numbers don't take to this kindly.
a0d0e21e 2322
6df41af2 2323=item Illegal number of bits in vec
399388f4 2324
6df41af2
GS
2325(F) The number of bits in vec() (the third argument) must be a power of
2326two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2327
2328=item Illegal octal digit %s
a0d0e21e 2329
d1be9408 2330(F) You used an 8 or 9 in an octal number.
a0d0e21e 2331
399388f4 2332=item Illegal octal digit %s ignored
748a9306 2333
d1be9408 2334(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2335Interpretation of the octal number stopped before the 8 or 9.
748a9306 2336
e0e4a6e3 2337=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2338
675fa9ff 2339(F) You wrote something like
c608e803
KW
2340
2341 (?+foo)
2342
2343The C<"+"> is valid only when followed by digits, indicating a
2344capturing group. See
2345L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2346
375ed12a
JH
2347=item Illegal suidscript
2348
2349(F) The script run under suidperl was somehow illegal.
2350
fe13d51d 2351=item Illegal switch in PERL5OPT: -%c
6ff81951 2352
6df41af2 2353(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2354following switches: B<-[CDIMUdmtw]>.
6ff81951 2355
6df41af2 2356=item Ill-formed CRTL environ value "%s"
81e118e0 2357
75b44862 2358(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2359internal environ array, and encountered an element without the C<=>
2360delimiter used to separate keys from values. The element is ignored.
09bef843 2361
6df41af2 2362=item Ill-formed message in prime_env_iter: |%s|
54310121 2363
be771a83
GS
2364(W internal) A warning peculiar to VMS. Perl tried to read a logical
2365name or CLI symbol definition when preparing to iterate over %ENV, and
2366didn't see the expected delimiter between key and value, so the line was
2367ignored.
54310121 2368
6df41af2 2369=item (in cleanup) %s
9607fc9c 2370
be771a83
GS
2371(W misc) This prefix usually indicates that a DESTROY() method raised
2372the indicated exception. Since destructors are usually called by the
2373system at arbitrary points during execution, and often a vast number of
2374times, the warning is issued only once for any number of failures that
2375would otherwise result in the same message being repeated.
6df41af2 2376
be771a83
GS
2377Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2378also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2379
e0e4a6e3
FC
2380=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2381in m/%s/
0d0b4b3b 2382
675fa9ff 2383(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2384expression inside the construct was completely empty, or if there are
2385too many or few operands for the number of operators. Perl is not smart
2386enough to give you a more precise indication as to what is wrong.
2387
6fbc9859
MH
2388=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2389parent '%s'
2c7d6b9c
RGS
2390
2391(F) The method resolution order (MRO) of the given class is not
2392C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2393documentation in L<mro> for more information.
2394
979699d9
JH
2395=item In EBCDIC the v-string components cannot exceed 2147483647
2396
2397(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2398Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2399encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2400
6a2ed79a 2401=item Infinite recursion in regex
1a147d38
YO
2402
2403(F) You used a pattern that references itself without consuming any input
6903afa2 2404text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2405either consume text or fail.
2406
6dbe9451
NC
2407=item Initialization of state variables in list context currently forbidden
2408
6903afa2
FC
2409(F) Currently the implementation of "state" only permits the
2410initialization of scalar variables in scalar context. Re-write
2411C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2412context. Constructions such as C<state (@a) = foo()> will be
2413supported in a future perl release.
6dbe9451 2414
2186f873
FC
2415=item %%s[%s] in scalar context better written as $%s[%s]
2416
2417(W syntax) In scalar context, you've used an array index/value slice
2418(indicated by %) to select a single element of an array. Generally
2419it's better to ask for a scalar value (indicated by $). The difference
2420is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2421returns and when evaluating its argument, while C<%foo[&bar]> provides
2422a list context to its subscript, which can do weird things if you're
2423expecting only one subscript. When called in list context, it also
2424returns the index (what C<&bar> returns) in addition to the value.
2425
2426=item %%s{%s} in scalar context better written as $%s{%s}
2427
2428(W syntax) In scalar context, you've used a hash key/value slice
2429(indicated by %) to select a single element of a hash. Generally it's
2430better to ask for a scalar value (indicated by $). The difference
2431is that C<$foo{&bar}> always behaves like a scalar, both in the value
2432it returns and when evaluating its argument, while C<@foo{&bar}> and
2433provides a list context to its subscript, which can do weird things
2434if you're expecting only one subscript. When called in list context,
2435it also returns the key in addition to the value.
2436
a0d0e21e
LW
2437=item Insecure dependency in %s
2438
8b1a09fc 2439(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2440The tainting mechanism is turned on when you're running setuid or
2441setgid, or when you specify B<-T> to turn it on explicitly. The
2442tainting mechanism labels all data that's derived directly or indirectly
2443from the user, who is considered to be unworthy of your trust. If any
2444such data is used in a "dangerous" operation, you get this error. See
2445L<perlsec> for more information.
a0d0e21e
LW
2446
2447=item Insecure directory in %s
2448
be771a83
GS
2449(F) You can't use system(), exec(), or a piped open in a setuid or
2450setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2451the world. Also, the PATH must not contain any relative directory.
2452See L<perlsec>.
a0d0e21e 2453
62f468fc 2454=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2455
2456(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2457setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2458C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2459supplied (or potentially supplied) by the user. The script must set
2460the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2461
0e9be77f
DM
2462=item Insecure user-defined property %s
2463
2464(F) Perl detected tainted data when trying to compile a regular
2465expression that contains a call to a user-defined character property
2466function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2467See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2468
b9ef414d
FC
2469=item Integer overflow in format string for %s
2470
2471(F) The indexes and widths specified in the format string of C<printf()>
2472or C<sprintf()> are too large. The numbers must not overflow the size of
2473integers for your architecture.
2474
a7ae9550
GS
2475=item Integer overflow in %s number
2476
35928bc5 2477(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2478either as a literal or as an argument to hex() or oct() is too big for
2479your architecture, and has been converted to a floating point number.
2480On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2481representable without overflow is 0xFFFFFFFF, 037777777777, or
24820b11111111111111111111111111111111 respectively. Note that Perl
2483transparently promotes all numbers to a floating point representation
2484internally--subject to loss of precision errors in subsequent
2485operations.
bbce6d69 2486
fc89ca81
FC
2487=item Integer overflow in srand
2488
2489(S overflow) The number you have passed to srand is too big to fit
2490in your architecture's integer representation. The number has been
2491replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2492architectures). This means you may be getting less randomness than
2493you expect, because different random seeds above the maximum will
2494return the same sequence of random numbers.
2495
46314c13
JP
2496=item Integer overflow in version
2497
18da5252
FC
2498=item Integer overflow in version %d
2499
784d71ed
FC
2500(W overflow) Some portion of a version initialization is too large for
2501the size of integers for your architecture. This is not a warning
f084e84f 2502because there is no rational reason for a version to try and use an
784d71ed
FC
2503element larger than typically 2**32. This is usually caused by trying
2504to use some odd mathematical operation as a version, like 100/9.
46314c13 2505
e0e4a6e3 2506=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2507
2508(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2509The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2510discovered.
2511
748a9306
LW
2512=item Internal inconsistency in tracking vforks
2513
be771a83
GS
2514(S) A warning peculiar to VMS. Perl keeps track of the number of times
2515you've called C<fork> and C<exec>, to determine whether the current call
2516to C<exec> should affect the current script or a subprocess (see
2517L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2518Perl is making a guess and treating this C<exec> as a request to
2519terminate the Perl script and execute the specified command.
748a9306 2520
870978ae
FC
2521=item internal %<num>p might conflict with future printf extensions
2522
2523(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2524formatting follows a slightly different set of rules when called from
2525C or XS code. Specifically, formats consisting of digits followed
2526by "p" (e.g., "%7p") are reserved for future use. If you see this
2527message, then an XS module tried to call that routine with one such
2528reserved format.
2529
e0e4a6e3 2530=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2531
fa816bf3 2532(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2533S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2534discovered.
a0d0e21e 2535
6df41af2
GS
2536=item %s (...) interpreted as function
2537
75b44862 2538(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2539followed by parentheses turns into a function, with all the list
64977eb6 2540operators arguments found inside the parentheses. See
13a2d996 2541L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2542
f51551f7
FC
2543=item In '(?...)', the '(' and '?' must be adjacent in regex;
2544marked by S<<-- HERE> in m/%s/
2545
2546(F) The two-character sequence C<"(?"> in this context in a regular
2547expression pattern should be an indivisible token, with nothing
2548intervening between the C<"("> and the C<"?">, but you separated them
2549with whitespace.
2550
09bef843
SB
2551=item Invalid %s attribute: %s
2552
a4a4c9e2 2553(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2554by Perl or by a user-supplied handler. See L<attributes>.
2555
2556=item Invalid %s attributes: %s
2557
a4a4c9e2 2558(F) The indicated attributes for a subroutine or variable were not
be771a83 2559recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2560
e0e4a6e3
FC
2561=item Invalid character in charnames alias definition; marked by
2562S<<-- HERE> in '%s
225fb84f
KW
2563
2564(F) You tried to create a custom alias for a character name, with
2565the C<:alias> option to C<use charnames> and the specified character in
2566the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2567
c8028aa6
TC
2568=item Invalid \0 character in %s for %s: %s\0%s
2569
fa3234e3
FC
2570(W syscalls) Embedded \0 characters in pathnames or other system call
2571arguments produce a warning as of 5.20. The parts after the \0 were
2572formerly ignored by system calls.
c8028aa6 2573
e0e4a6e3 2574=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2575
2576(F) Only certain characters are valid for character names. The
2577indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2578
c635e13b
PP
2579=item Invalid conversion in %s: "%s"
2580
be771a83
GS
2581(W printf) Perl does not understand the given format conversion. See
2582L<perlfunc/sprintf>.
c635e13b 2583
e0e4a6e3
FC
2584=item Invalid escape in the specified encoding in regex; marked by
2585S<<-- HERE> in m/%s/
9e08bc66 2586
98d31c73 2587(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2588didn't correspond to a single character through the conversion
2589from the encoding specified by the encoding pragma.
98d31c73
FC
2590The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2591instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2592The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2593escape was discovered.
2594
8149aa9f
FC
2595=item Invalid hexadecimal number in \N{U+...}
2596
e0e4a6e3
FC
2597=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2598S<<-- HERE> in m/%s/
aec0ef10 2599
8149aa9f 2600(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2601number. Either it is empty, or you tried to use a character other than
26020 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2603
6651ba0b
FC
2604=item Invalid module name %s with -%c option: contains single ':'
2605
2606(F) The module argument to perl's B<-m> and B<-M> command-line options
2607cannot contain single colons in the module name, but only in the
2608arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2609B<-MFoo:Bar=baz> is not.
2610
2c7d6b9c
RGS
2611=item Invalid mro name: '%s'
2612
162a3e34
FC
2613(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2614where C<foo> is not a valid method resolution order (MRO). Currently,
2615the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2616a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2617
40e4140b
FC
2618=item Invalid negative number (%s) in chr
2619
2620(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2621not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2622character (U+FFFD).
2623
6651ba0b
FC
2624=item invalid option -D%c, use -D'' to see choices
2625
8ff21bfe
FC
2626(S debugging) Perl was called with invalid debugger flags. Call perl
2627with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2628See also L<perlrun/-Dletters>.
6651ba0b 2629
e0e4a6e3 2630=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2631
2632(F) The range specified in a character class had a minimum character
7253e4e3
RK
2633greater than the maximum character. One possibility is that you forgot the
2634C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2635up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2636problem was discovered. See L<perlre>.
6df41af2 2637
d1573ac7 2638=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2639
2640(F) The range specified in the tr/// or y/// operator had a minimum
2641character greater than the maximum character. See L<perlop>.
2642
09bef843
SB
2643=item Invalid separator character %s in attribute list
2644
0120eecf 2645(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2646elements of an attribute list. If the previous attribute had a
2647parenthesised parameter list, perhaps that list was terminated too soon.
2648See L<attributes>.
09bef843 2649
b4581f09
JH
2650=item Invalid separator character %s in PerlIO layer specification %s
2651
2bfc5f71
FC
2652(W layer) When pushing layers onto the Perl I/O system, something other
2653than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2654If the previous attribute had a parenthesised parameter list, perhaps that
2655list was terminated too soon.
2656
2c86d456
DG
2657=item Invalid strict version format (%s)
2658
fa816bf3 2659(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2660A "strict" version number is a positive decimal number (integer or
2661decimal-fraction) without exponentiation or else a dotted-decimal
2662v-string with a leading 'v' character and at least three components.
a6485a24 2663The parenthesized text indicates which criteria were not met.
2c86d456
DG
2664See the L<version> module for more details on allowed version formats.
2665
49704364 2666=item Invalid type '%s' in %s
96e4d5b1 2667
49704364
LW
2668(F) The given character is not a valid pack or unpack type.
2669See L<perlfunc/pack>.
6728c851 2670
49704364 2671(W) The given character is not a valid pack or unpack type but used to be
75b44862 2672silently ignored.
96e4d5b1 2673
2c86d456
DG
2674=item Invalid version format (%s)
2675
fa816bf3 2676(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2677A "lax" version number is a positive decimal number (integer or
2678decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2679v-string. If the v-string has fewer than three components, it
2680must have a leading 'v' character. Otherwise, the leading 'v' is
2681optional. Both decimal and dotted-decimal versions may have a
2682trailing "alpha" component separated by an underscore character
2683after a fractional or dotted-decimal component. The parenthesized
2684text indicates which criteria were not met. See the L<version> module
2685for more details on allowed version formats.
46314c13 2686
798ae1b7
DG
2687=item Invalid version object
2688
fa816bf3
FC
2689(F) The internal structure of the version object was invalid.
2690Perhaps the internals were modified directly in some way or
2691an arbitrary reference was blessed into the "version" class.
798ae1b7 2692
cd209d9d 2693=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2694marked by S<<-- HERE> in m/%s/
675fa9ff 2695
cd209d9d 2696(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2697this context in a regular expression pattern should be an
2698indivisible token, with nothing intervening between the C<"(">
cd209d9d 2699and the C<"*">, but you separated them.
675fa9ff 2700
a0d0e21e
LW
2701=item ioctl is not implemented
2702
2703(F) Your machine apparently doesn't implement ioctl(), which is pretty
2704strange for a machine that supports C.
2705
c289d2f7
JH
2706=item ioctl() on unopened %s
2707
2708(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2709Check your control flow and number of arguments.
c289d2f7 2710
fe13d51d 2711=item IO layers (like '%s') unavailable
363c40c4
SB
2712
2713(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2714you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2715with 'useperlio'.
2716
80cbd5ad
JH
2717=item IO::Socket::atmark not implemented on this architecture
2718
2719(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2720neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2721
4f650b80 2722=item $* is no longer supported
b4581f09 2723
4f650b80 2724(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2725perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2726previous versions of perl the use of C<$*> enabled or disabled multi-line
2727matching within a string.
4fd19576
B
2728
2729Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2730modifiers. You can enable C</m> for a lexical scope (even a whole file)
2731with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2732then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2733
8ae1fe26
RGS
2734=item $# is no longer supported
2735
a58ac25e 2736(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2737perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2738should use the printf/sprintf functions instead.
8ae1fe26 2739
ccf3535a 2740=item '%s' is not a code reference
6ad11d81 2741
6903afa2
FC
2742(W overload) The second (fourth, sixth, ...) argument of
2743overload::constant needs to be a code reference. Either
2744an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2745
ccf3535a 2746=item '%s' is not an overloadable type
6ad11d81 2747
04a80ee0
RGS
2748(W overload) You tried to overload a constant type the overload package is
2749unaware of.
6ad11d81 2750
5a25739d
FC
2751=item -i used with no filenames on the command line, reading from STDIN
2752
2753(S inplace) The C<-i> option was passed on the command line, indicating
2754that the script is intended to edit files in place, but no files were
2755given. This is usually a mistake, since editing STDIN in place doesn't
2756make sense, and can be confusing because it can make perl look like
2757it is hanging when it is really just trying to read from STDIN. You
2758should either pass a filename to edit, or remove C<-i> from the command
2759line. See L<perlrun> for more details.
2760
aec0ef10 2761=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2762
2763(P) The regular expression parser is confused.
2764
0953b66b
FC
2765=item keys on reference is experimental
2766
0773cb3e
FC
2767(S experimental::autoderef) C<keys> with a scalar argument is experimental
2768and may change or be removed in a future Perl version. If you want to
2769take the risk of using this feature, simply disable this warning:
0953b66b 2770
d401967c 2771 no warnings "experimental::autoderef";
0953b66b 2772
a0d0e21e
LW
2773=item Label not found for "last %s"
2774
be771a83
GS
2775(F) You named a loop to break out of, but you're not currently in a loop
2776of that name, not even if you count where you were called from. See
2777L<perlfunc/last>.
a0d0e21e
LW
2778
2779=item Label not found for "next %s"
2780
2781(F) You named a loop to continue, but you're not currently in a loop of
2782that name, not even if you count where you were called from. See
2783L<perlfunc/last>.
2784
2785=item Label not found for "redo %s"
2786
2787(F) You named a loop to restart, but you're not currently in a loop of
2788that name, not even if you count where you were called from. See
2789L<perlfunc/last>.
2790
85ab1d1d 2791=item leaving effective %s failed
5ff3f7a4 2792
85ab1d1d 2793(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2794effective uids or gids failed.
2795
49704364
LW
2796=item length/code after end of string in unpack
2797
d7f8936a 2798(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2799length/code combination tried to obtain more data. This results in
2800an undefined value for the length. See L<perlfunc/pack>.
49704364 2801
25e26107 2802=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2803
0d46a4e7
FC
2804(W syntax) You used length() on either an array or a hash when you
2805probably wanted a count of the items.
e508c8a4
MH
2806
2807Array size can be obtained by doing:
2808
2809 scalar(@array);
2810
2811The number of items in a hash can be obtained by doing:
2812
2813 scalar(keys %hash);
2814
f0e67a1d
Z
2815=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2816
d4fe7078
RS
2817(F) An extension is attempting to insert text into the current parse
2818(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2819couldn't be part of the current input. This is an inherent pitfall
2820of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2821it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2822
2823=item Lexing code internal error (%s)
2824
2825(F) Lexing code supplied by an extension violated the lexer's API in a
2826detectable way.
2827
69282e91 2828=item listen() on closed socket %s
a0d0e21e 2829
be771a83
GS
2830(W closed) You tried to do a listen on a closed socket. Did you forget
2831to check the return value of your socket() call? See
2832L<perlfunc/listen>.
a0d0e21e 2833
6651ba0b
FC
2834=item List form of piped open not implemented
2835
2836(F) On some platforms, notably Windows, the three-or-more-arguments
2837form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2838Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2839
b35b96b6
JH
2840=item localtime(%f) failed
2841
2842(W overflow) You called C<localtime> with a number that it could not handle:
2843too large, too small, or NaN. The returned value is C<undef>.
2844
bcd05b94 2845=item localtime(%f) too large
8b56d6ff 2846
e9200be3 2847(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2848than it can reliably handle and C<localtime> probably returned the
6903afa2 2849wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2850not-a-number value).
2851
bcd05b94 2852=item localtime(%f) too small
fc003d4b 2853
e9200be3 2854(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2855than it can reliably handle and C<localtime> probably returned the
e7a1a147 2856wrong date.
8b56d6ff 2857
58e23c8d 2858=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2859
2860(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2861handle. This restriction may be eased in a future release.
2e50fd82 2862
b88df990
NC
2863=item Lost precision when %s %f by 1
2864
e63e8a91
FC
2865(W imprecision) The value you attempted to increment or decrement by one
2866is too large for the underlying floating point representation to store
2867accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2868warning because it has already switched from integers to floating point
2869when values are too large for integers, and now even floating point is
2870insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2871
93fad930 2872=item lstat() on filehandle%s
2f7da168
RK
2873
2874(W io) You tried to do an lstat on a filehandle. What did you mean
2875by that? lstat() makes sense only on filenames. (Perl did a fstat()
2876instead on the filehandle.)
2877
345d70e3 2878=item lvalue attribute %s already-defined subroutine
bb3abb05 2879
345d70e3
FC
2880(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2881attribute on or off on a Perl subroutine that is already defined
2882does not always work properly. It may or may not do what you
2883want, depending on what code is inside the subroutine, with exact
2884details subject to change between Perl versions. Only do this
2885if you really know what you are doing.
bb3abb05 2886
885ef6f5
GG
2887=item lvalue attribute ignored after the subroutine has been defined
2888
345d70e3
FC
2889(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2890subroutine an lvalue subroutine after it has been defined is
2891not permitted. To make the subroutine an lvalue subroutine,
2892add the lvalue attribute to the definition, or put the C<sub
2893foo :lvalue;> declaration before the definition.
2894
2895See also L<attributes.pm|attributes>.
885ef6f5 2896
6f1b3ab0
FC
2897=item Magical list constants are not supported
2898
2899(F) You assigned a magical array to a stash element, and then tried
2900to use the subroutine from the same slot. You are asking Perl to do
2901something it cannot do, details subject to change between Perl versions.
2902
2db62bbc 2903=item Malformed integer in [] in pack
49704364 2904
2db62bbc 2905(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2906are permitted. See L<perlfunc/pack>.
2907
2908=item Malformed integer in [] in unpack
2909
2db62bbc 2910(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2911are permitted. See L<perlfunc/pack>.
2912
6df41af2
GS
2913=item Malformed PERLLIB_PREFIX
2914
2915(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2916
2917 prefix1;prefix2
2918
2919or
6df41af2
GS
2920 prefix1 prefix2
2921
be771a83
GS
2922with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2923a builtin library search path, prefix2 is substituted. The error may
2924appear if components are not found, or are too long. See
fecfaeb8 2925"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2926
2f758a16
ST
2927=item Malformed prototype for %s: %s
2928
d37a9538
ST
2929(F) You tried to use a function with a malformed prototype. The
2930syntax of function prototypes is given a brief compile-time check for
2931obvious errors like invalid characters. A more rigorous check is run
2932when the function is called.
30d9c59b
Z
2933Perhaps the function's author was trying to write a subroutine signature
2934but didn't enable that feature first (C<use feature 'signatures'>),
2935so the signature was instead interpreted as a bad prototype.
2f758a16 2936
ba210ebe
JH
2937=item Malformed UTF-8 character (%s)
2938
4d6f11e5 2939(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2940encoding rules, even though it had the UTF8 flag on.
ba210ebe 2941
2575c402
JW
2942One possible cause is that you set the UTF8 flag yourself for data that
2943you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 29448-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2945
2946If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2947sequences are handled gracefully, but if you use C<:utf8>, the flag is
2948set without validating the data, possibly resulting in this error
2949message.
2950
2951See also L<Encode/"Handling Malformed Data">.
901b21bf 2952
107160e2
KW
2953=item Malformed UTF-8 character immediately after '%s'
2954
2955(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2956encoding rules. The message prints out the properly encoded characters
2957just before the first bad one. If C<utf8> warnings are enabled, a
2958warning is generated that gives more details about the type of
2959malformation.
2960
bde9e88d 2961=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2962
2963(F) The charnames handler returned malformed UTF-8.
2964
4a5d3a93
FC
2965=item Malformed UTF-8 string in '%c' format in unpack
2966
2967(F) You tried to unpack something that didn't comply with UTF-8 encoding
2968rules and perl was unable to guess how to make more progress.
2969
f337b084
TH
2970=item Malformed UTF-8 string in pack
2971
2972(F) You tried to pack something that didn't comply with UTF-8 encoding
2973rules and perl was unable to guess how to make more progress.
2974
2975=item Malformed UTF-8 string in unpack
2976
2977(F) You tried to unpack something that didn't comply with UTF-8 encoding
2978rules and perl was unable to guess how to make more progress.
2979
4a5d3a93 2980=item Malformed UTF-16 surrogate
f337b084 2981
4a5d3a93
FC
2982(F) Perl thought it was reading UTF-16 encoded character data but while
2983doing it Perl met a malformed Unicode surrogate.
2984
30d9c59b
Z
2985=item Mandatory parameter follows optional parameter
2986
2987(F) In a subroutine signature, you wrote something like "$a = undef,
2988$b", making an earlier parameter optional and a later one mandatory.
2989Parameters are filled from left to right, so it's impossible for the
2990caller to omit an earlier one and pass a later one. If you want to act
2991as if the parameters are filled from right to left, declare the rightmost
2992optional and then shuffle the parameters around in the subroutine's body.
2993
2d88a86a
KW
2994=item Matched non-Unicode code point 0x%X against Unicode property; may
2995not be portable
2996
2997(S non_unicode) Perl allows strings to contain a superset of
2998Unicode code points; each code point may be as large as what is storable
2999in an unsigned integer on your system, but these may not be accepted by
3000other languages/systems. This message occurs when you matched a string
3001containing such a code point against a regular expression pattern, and
3002the code point was matched against a Unicode property, C<\p{...}> or
3003C<\P{...}>. Unicode properties are only defined on Unicode code points,
3004so the result of this match is undefined by Unicode, but Perl (starting
3005in v5.20) treats non-Unicode code points as if they were typical
3006unassigned Unicode ones, and matched this one accordingly. Whether a
3007given property matches these code points or not is specified in
3008L<perluniprops/Properties accessible through \p{} and \P{}>.
3009
3010This message is suppressed (unless it has been made fatal) if it is
3011immaterial to the results of the match if the code point is Unicode or
3012not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3013the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3014Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3015every code point except these 22.)
3016
3017Getting this message indicates that the outcome of the match arguably
3018should have been the opposite of what actually happened. If you think
3019that is the case, you may wish to make the C<non_unicode> warnings
3020category fatal; if you agree with Perl's decision, you may wish to turn
3021off this category.
3022
3023See L<perlunicode/Beyond Unicode code points> for more information.
3024
e0e4a6e3
FC
3025=item %s matches null string many times in regex; marked by S<<-- HERE> in
3026m/%s/
4a5d3a93
FC
3027
3028(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3029regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3030shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3031See L<perlre>.
f337b084 3032
de42a5a9 3033=item Maximal count of pending signals (%u) exceeded
2563cec5 3034
6903afa2 3035(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3036usually indicates that your operating system tried to deliver signals
3037too fast (with a very high priority), starving the perl process from
3038resources it would need to reach a point where it can process signals
6903afa2 3039safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3040
25f58aea
PN
3041=item "%s" may clash with future reserved word
3042
3043(W) This warning may be due to running a perl5 script through a perl4
3044interpreter, especially if the word that is being warned about is
3045"use" or "my".
3046
0d2487cd 3047=item '%' may not be used in pack
6df41af2
GS
3048
3049(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3050checksumming process loses information, and you can't go the other way.
3051See L<perlfunc/unpack>.
6df41af2 3052
a0d0e21e
LW
3053=item Method for operation %s not found in package %s during blessing
3054
3055(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3056doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3057
3cdd684c
TP
3058=item Method %s not permitted
3059
3060See Server error.
3061
a0d0e21e
LW
3062=item Might be a runaway multi-line %s string starting on line %d
3063
3064(S) An advisory indicating that the previous error may have been caused
3065by a missing delimiter on a string or pattern, because it eventually
3066ended earlier on the current line.
3067
3068=item Misplaced _ in number
3069
d4ced10d
JH
3070(W syntax) An underscore (underbar) in a numeric constant did not
3071separate two digits.
a0d0e21e 3072
7baa4690
HS
3073=item Missing argument in %s
3074
3664866e
AB
3075(W missing) You called a function with fewer arguments than other
3076arguments you supplied indicated would be needed.
3077
3078Currently only emitted when a printf-type format required more
3079arguments than were supplied, but might be used in the future for
3080other cases where we can statically determine that arguments to
3081functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3082
9e81e6a1
RGS
3083=item Missing argument to -%c
3084
3085(F) The argument to the indicated command line switch must follow
3086immediately after the switch, without intervening spaces.
3087
ff3f963a 3088=item Missing braces on \N{}
423cee85 3089
e0e4a6e3 3090=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3091
4a2d328f 3092(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3093double-quotish context. This can also happen when there is a space
3094(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3095This modifier does not change the requirement that the brace immediately
3096follow the C<\N>.
423cee85 3097
f0a2b745
KW
3098=item Missing braces on \o{}
3099
3100(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3101
a0d0e21e
LW
3102=item Missing comma after first argument to %s function
3103
3104(F) While certain functions allow you to specify a filehandle or an
3105"indirect object" before the argument list, this ain't one of them.
3106
06eaf0bc
GS
3107=item Missing command in piped open
3108
be771a83
GS
3109(W pipe) You used the C<open(FH, "| command")> or
3110C<open(FH, "command |")> construction, but the command was missing or
3111blank.
06eaf0bc 3112
961ce445
RGS
3113=item Missing control char name in \c
3114
3115(F) A double-quoted string ended with "\c", without the required control
3116character name.
3117
591f5ca2
FC
3118=item Missing ']' in prototype for %s : %s
3119
bfe11873 3120(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3121
8767b1ab 3122=item Missing name in "%s sub"
6df41af2 3123
87444db5 3124(F) The syntax for lexically scoped subroutines requires that
be771a83 3125they have a name with which they can be found.
6df41af2
GS
3126
3127=item Missing $ on loop variable
3128
be771a83
GS
3129(F) Apparently you've been programming in B<csh> too much. Variables
3130are always mentioned with the $ in Perl, unlike in the shells, where it
3131can vary from one line to the next.
6df41af2 3132
cc507455 3133=item (Missing operator before %s?)
748a9306 3134
56da5a46
RGS
3135(S syntax) This is an educated guess made in conjunction with the message
3136"%s found where operator expected". Often the missing operator is a comma.
748a9306 3137
f51551f7
FC
3138=item Missing or undefined argument to require
3139
3140(F) You tried to call require with no argument or with an undefined
3141value as an argument. Require expects either a package name or a
3142file-specification as an argument. See L<perlfunc/require>.
3143
e0e4a6e3 3144=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3145
ff3f963a
KW
3146(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3147
4a68bf9d 3148=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3149
d32207c9
FC
3150(F) C<\N> has two meanings.
3151
3152The traditional one has it followed by a name enclosed in braces,
3153meaning the character (or sequence of characters) given by that
fa816bf3 3154name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3155double-quoted strings and regular expression patterns. In patterns,
3156it doesn't have the meaning an unescaped C<*> does.
3157
3158Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3159in patterns, namely to match a non-newline character. (This is short
3160for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3161
3162This can lead to some ambiguities. When C<\N> is not followed immediately
3163by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3164form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3165means to match the given quantity of non-newlines (in these examples,
31663; and 5 or more, respectively). In all other case, where there is a
3167C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3168
3169However, if there is no matching C<}>, Perl doesn't know if it was
3170mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3171If you meant the former, add the right brace; if you meant the latter,
3172escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3173
d98d5fff 3174=item Missing right curly or square bracket
a0d0e21e 3175
be771a83
GS
3176(F) The lexer counted more opening curly or square brackets than closing
3177ones. As a general rule, you'll find it's missing near the place you
3178were last editing.
a0d0e21e 3179
6df41af2
GS
3180=item (Missing semicolon on previous line?)
3181
56da5a46
RGS
3182(S syntax) This is an educated guess made in conjunction with the message
3183"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3184the previous line just because you saw this message.
3185
a0d0e21e
LW
3186=item Modification of a read-only value attempted
3187
3188(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3189constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3190catches that. But an easy way to do the same thing is:
3191
3192 sub mod { $_[0] = 1 }
3193 mod(2);
3194
3195Another way is to assign to a substr() that's off the end of the string.
3196
c5674021
PDF
3197Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3198is aliased to a constant in the look I<LIST>:
3199
b7e4ecc1
FC
3200 $x = 1;
3201 foreach my $n ($x, 2) {
3202 $n *= 2; # modifies the $x, but fails on attempt to
3203 } # modify the 2
c5674021 3204
7a4340ed 3205=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3206
3207(F) You tried to make an array value spring into existence, and the
3208subscript was probably negative, even counting from end of the array
3209backwards.
3210
7a4340ed 3211=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3212
be771a83
GS
3213(P) You tried to make a hash value spring into existence, and it
3214couldn't be created for some peculiar reason.
a0d0e21e
LW
3215
3216=item Module name must be constant
3217
3218(F) Only a bare module name is allowed as the first argument to a "use".
3219
be98fb35 3220=item Module name required with -%c option
6df41af2 3221
be98fb35
GS
3222(F) The C<-M> or C<-m> options say that Perl should load some module, but
3223you omitted the name of the module. Consult L<perlrun> for full details
3224about C<-M> and C<-m>.
6df41af2 3225
fe13d51d 3226=item More than one argument to '%s' open
ed9aa3b7 3227
6903afa2 3228(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3229can happen if you are trying to open a pipe to a command that takes a
3230list of arguments, but have forgotten to specify a piped open mode.
3231See L<perlfunc/open> for details.
3232
85396b18
FC
3233=item mprotect for COW string %p %u failed with %d
3234
3235(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3236L<perlguts/"Copy on Write">), but a shared string buffer
3237could not be made read-only.
3238
92951bce
FC
3239=item mprotect for %p %u failed with %d
3240
85396b18
FC
3241(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3242but an op tree could not be made read-only.
3243
3244=item mprotect RW for COW string %p %u failed with %d
3245
3246(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3247L<perlguts/"Copy on Write">), but a read-only shared string
3248buffer could not be made mutable.
3249
92951bce
FC
3250=item mprotect RW for %p %u failed with %d
3251
3252(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3253L<perlhacktips>), but a read-only op tree could not be made
3254mutable before freeing the ops.
92951bce 3255
a0d0e21e
LW
3256=item msg%s not implemented
3257
3258(F) You don't have System V message IPC on your system.
3259
3260=item Multidimensional syntax %s not supported
3261
75b44862
GS
3262(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3263They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3264
49704364 3265=item '/' must follow a numeric type in unpack
6df41af2 3266
49704364
LW
3267(F) You had an unpack template that contained a '/', but this did not
3268follow some unpack specification producing a numeric value.
3269See L<perlfunc/pack>.
6df41af2
GS
3270
3271=item "my sub" not yet implemented
3272
be771a83
GS
3273(F) Lexically scoped subroutines are not yet implemented. Don't try
3274that yet.
6df41af2 3275
5a25739d
FC
3276=item "my %s" used in sort comparison
3277
3278(W syntax) The package variables $a and $b are used for sort comparisons.
3279You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3280sort comparison block, and the variable had earlier been declared as a
3281lexical variable. Either qualify the sort variable with the package
3282name, or rename the lexical variable.
3283
fd1b7234 3284=item "my" variable %s can't be in a package
6df41af2 3285
be771a83
GS
3286(F) Lexically scoped variables aren't in a package, so it doesn't make
3287sense to try to declare one with a package qualifier on the front. Use
3288local() if you want to localize a package variable.
09bef843 3289
8149aa9f
FC
3290=item Name "%s::%s" used only once: possible typo
3291
c59aba6c
FC
3292(W once) Typographical errors often show up as unique variable
3293names. If you had a good reason for having a unique name, then
3294just mention it again somehow to suppress the message. The C<our>
08a33b6b 3295declaration is also provided for this purpose.
c59aba6c 3296
66a1f5ec
FC
3297NOTE: This warning detects package symbols that have been used
3298only once. This means lexical variables will never trigger this
3299warning. It also means that all of the package variables $c, @c,
3300%c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3301format) are considered the same; if a program uses $c only once
3302but also uses any of the others it will not trigger this warning.
3303Symbols beginning with an underscore and symbols using special
3304identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3305
e0e4a6e3 3306=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3307
3308(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3309exactly 3 digits long. This helps catch some ambiguities. If your
3310constant is too short, add leading zeros, like
3311
3312 (?[ [ \078 ] ]) # Syntax error!
3313 (?[ [ \0078 ] ]) # Works
3314 (?[ [ \007 8 ] ]) # Clearer
3315
3316The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3317need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3318two separate things, you need to separate them:
0d0b4b3b
KW
3319
3320 (?[ [ \7776 ] ]) # Syntax error!
3321 (?[ [ \o{7776} ] ]) # One meaning