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Disallow omitting % and @ on hash and array names
[perl5.git] / pod / perldiag.pod
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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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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.
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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.
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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__}>
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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
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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
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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.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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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
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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
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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
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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
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76to be an object method (see L<perlsub/"Subroutine Attributes"> or
77L<attributes>).
43192e07 78
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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
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89you thought. Normally it's pretty easy to disambiguate it by supplying
90a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 91
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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
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99=item Ambiguous use of %c resolved as operator %c
100
7c7af292 101(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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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
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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
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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
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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
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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<${foo([2])}>.
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128
129In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130to disambiguate between array subscripts and character classes.
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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
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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
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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
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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
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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
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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
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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
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179=item Argument list not closed for PerlIO layer "%s"
180
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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
2d8eb851 189=item charnames alias definitions may not contain a sequence of multiple spaces
bd299e29 190
2d8eb851 191(F) You defined a character name which had multiple space
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192characters in a row. Change them to single spaces. Usually these
193names are defined in the C<:alias> import argument to C<use charnames>, but
194they could be defined by a translator installed into C<$^H{charnames}>.
195See L<charnames/CUSTOM ALIASES>.
bd299e29 196
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197=item charnames alias definitions may not contain trailing white-space
198
199(F) You defined a character name which ended in a space
200character. Remove the trailing space(s). Usually these names are
201defined in the C<:alias> import argument to C<use charnames>, but they
202could be defined by a translator installed into C<$^H{charnames}>.
203See L<charnames/CUSTOM ALIASES>.
204
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205=item assertion botched: %s
206
21b5e840 207(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 208
0eacef8e 209=item Assertion %s failed: file "%s", line %d
a0d0e21e 210
21b5e840 211(X) A general assertion failed. The file in question must be examined.
a0d0e21e 212
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213=item Assigning non-zero to $[ is no longer possible
214
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215(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
216the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 217
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218=item Assignment to both a list and a scalar
219
220(F) If you assign to a conditional operator, the 2nd and 3rd arguments
221must either both be scalars or both be lists. Otherwise Perl won't
222know which context to supply to the right side.
223
2393f1b9 224=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 225
49293501 226(F) The failing code has attempted to get or set a key which is not in
2393f1b9 227the current set of allowed keys of a restricted hash.
49293501 228
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229=item Attempt to bless into a freed package
230
231(F) You wrote C<bless $foo> with one argument after somehow causing
232the current package to be freed. Perl cannot figure out what to
233do, so it throws up in hands in despair.
234
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235=item Attempt to bless into a reference
236
237(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 238the name of the package to bless the resulting object into. You've
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239supplied instead a reference to something: perhaps you wrote
240
241 bless $self, $proto;
242
243when you intended
244
245 bless $self, ref($proto) || $proto;
246
247If you actually want to bless into the stringified version
248of the reference supplied, you need to stringify it yourself, for
249example by:
250
251 bless $self, "$proto";
252
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253=item Attempt to clear deleted array
254
255(S debugging) An array was assigned to when it was being freed.
256Freed values are not supposed to be visible to Perl code. This
257can also happen if XS code calls C<av_clear> from a custom magic
258callback on the array.
259
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260=item Attempt to delete disallowed key '%s' from a restricted hash
261
262(F) The failing code attempted to delete from a restricted hash a key
263which is not in its key set.
264
265=item Attempt to delete readonly key '%s' from a restricted hash
266
267(F) The failing code attempted to delete a key whose value has been
268declared readonly from a restricted hash.
269
de42a5a9 270=item Attempt to free non-arena SV: 0x%x
a0d0e21e 271
f84fe999 272(S internal) All SV objects are supposed to be allocated from arenas
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273that will be garbage collected on exit. An SV was discovered to be
274outside any of those arenas.
a0d0e21e 275
12578ffb 276=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 277
f84fe999 278(S internal) Perl maintains a reference-counted internal table of
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279strings to optimize the storage and access of hash keys and other
280strings. This indicates someone tried to decrement the reference count
281of a string that can no longer be found in the table.
bbce6d69 282
7d5b40b4 283=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 284
f84fe999 285(S debugging) Mortalized values are supposed to be freed by the
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286free_tmps() routine. This indicates that something else is freeing the
287SV before the free_tmps() routine gets a chance, which means that the
288free_tmps() routine will be freeing an unreferenced scalar when it does
289try to free it.
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290
291=item Attempt to free unreferenced glob pointers
292
f84fe999 293(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 294
7d5b40b4 295=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 296
8f7e4d2c 297(S internal) Perl went to decrement the reference count of a scalar to
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298see if it would go to 0, and discovered that it had already gone to 0
299earlier, and should have been freed, and in fact, probably was freed.
300This could indicate that SvREFCNT_dec() was called too many times, or
301that SvREFCNT_inc() was called too few times, or that the SV was
302mortalized when it shouldn't have been, or that memory has been
303corrupted.
a0d0e21e 304
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305=item Attempt to pack pointer to temporary value
306
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307(W pack) You tried to pass a temporary value (like the result of a
308function, or a computed expression) to the "p" pack() template. This
309means the result contains a pointer to a location that could become
310invalid anytime, even before the end of the current statement. Use
311literals or global values as arguments to the "p" pack() template to
312avoid this warning.
84902520 313
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314=item Attempt to reload %s aborted.
315
316(F) You tried to load a file with C<use> or C<require> that failed to
317compile once already. Perl will not try to compile this file again
318unless you delete its entry from %INC. See L<perlfunc/require> and
319L<perlvar/%INC>.
320
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321=item Attempt to set length of freed array
322
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323(W misc) You tried to set the length of an array which has
324been freed. You can do this by storing a reference to the
325scalar representing the last index of an array and later
326assigning through that reference. For example
1b20cd17
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327
328 $r = do {my @a; \$#a};
329 $$r = 503
330
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331=item Attempt to use reference as lvalue in substr
332
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333(W substr) You supplied a reference as the first argument to substr()
334used as an lvalue, which is pretty strange. Perhaps you forgot to
335dereference it first. See L<perlfunc/substr>.
b7a902f4 336
c32124fe
NC
337=item Attribute "locked" is deprecated
338
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339(D deprecated) You have used the attributes pragma to modify the
340"locked" attribute on a code reference. The :locked attribute is
341obsolete, has had no effect since 5005 threads were removed, and
342will be removed in a future release of Perl 5.
c32124fe 343
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344=item Attribute prototype(%s) discards earlier prototype attribute in same sub
345
346(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
347example. Since each sub can only have one prototype, the earlier
348declaration(s) are discarded while the last one is applied.
349
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350=item Attribute "unique" is deprecated
351
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352(D deprecated) You have used the attributes pragma to modify
353the "unique" attribute on an array, hash or scalar reference.
354The :unique attribute has had no effect since Perl 5.8.8, and
355will be removed in a future release of Perl 5.
f1a3ce43 356
ccce04a4
FC
357=item av_reify called on tied array
358
359(S debugging) This indicates that something went wrong and Perl got I<very>
360confused about C<@_> or C<@DB::args> being tied.
361
de42a5a9 362=item Bad arg length for %s, is %u, should be %d
a0d0e21e 363
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364(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
365or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 366S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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367S<sizeof(struct shmid_ds *)>.
368
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369=item Bad evalled substitution pattern
370
496a33f5 371(F) You've used the C</e> switch to evaluate the replacement for a
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372substitution, but perl found a syntax error in the code to evaluate,
373most likely an unexpected right brace '}'.
374
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375=item Bad filehandle: %s
376
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377(F) A symbol was passed to something wanting a filehandle, but the
378symbol has no filehandle associated with it. Perhaps you didn't do an
379open(), or did it in another package.
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380
381=item Bad free() ignored
382
be771a83 383(S malloc) An internal routine called free() on something that had never
fa816bf3 384been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 385setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 386
9ea8bc6d 387This message can be seen quite often with DB_File on systems with "hard"
6903afa2 388dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 389which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 390
aa689395
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391=item Bad hash
392
393(P) One of the internal hash routines was passed a null HV pointer.
394
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395=item Badly placed ()'s
396
397(A) You've accidentally run your script through B<csh> instead
398of Perl. Check the #! line, or manually feed your script into
399Perl yourself.
400
a7cb8dae 401=item Bad name after %s
a0d0e21e 402
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403(F) You started to name a symbol by using a package prefix, and then
404didn't finish the symbol. In particular, you can't interpolate outside
405of quotes, so
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406
407 $var = 'myvar';
408 $sym = mypack::$var;
409
410is not the same as
411
412 $var = 'myvar';
413 $sym = "mypack::$var";
414
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415=item Bad plugin affecting keyword '%s'
416
417(F) An extension using the keyword plugin mechanism violated the
418plugin API.
419
4ad56ec9
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420=item Bad realloc() ignored
421
6903afa2
FC
422(S malloc) An internal routine called realloc() on something that
423had never been malloc()ed in the first place. Mandatory, but can
424be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 425
a0d0e21e
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426=item Bad symbol for array
427
428(P) An internal request asked to add an array entry to something that
429wasn't a symbol table entry.
430
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431=item Bad symbol for dirhandle
432
433(P) An internal request asked to add a dirhandle entry to something
434that wasn't a symbol table entry.
435
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436=item Bad symbol for filehandle
437
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438(P) An internal request asked to add a filehandle entry to something
439that wasn't a symbol table entry.
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440
441=item Bad symbol for hash
442
443(P) An internal request asked to add a hash entry to something that
444wasn't a symbol table entry.
445
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446=item Bareword found in conditional
447
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448(W bareword) The compiler found a bareword where it expected a
449conditional, which often indicates that an || or && was parsed as part
450of the last argument of the previous construct, for example:
34d09196
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451
452 open FOO || die;
453
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454It may also indicate a misspelled constant that has been interpreted as
455a bareword:
34d09196
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456
457 use constant TYPO => 1;
458 if (TYOP) { print "foo" }
459
460The C<strict> pragma is useful in avoiding such errors.
461
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462=item Bareword "%s" not allowed while "strict subs" in use
463
464(F) With "strict subs" in use, a bareword is only allowed as a
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465subroutine identifier, in curly brackets or to the left of the "=>"
466symbol. Perhaps you need to predeclare a subroutine?
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467
468=item Bareword "%s" refers to nonexistent package
469
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470(W bareword) You used a qualified bareword of the form C<Foo::>, but the
471compiler saw no other uses of that namespace before that point. Perhaps
472you need to predeclare a package?
6df41af2 473
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474=item BEGIN failed--compilation aborted
475
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476(F) An untrapped exception was raised while executing a BEGIN
477subroutine. Compilation stops immediately and the interpreter is
478exited.
a0d0e21e 479
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480=item BEGIN not safe after errors--compilation aborted
481
482(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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483implies a C<BEGIN {}>) after one or more compilation errors had already
484occurred. Since the intended environment for the C<BEGIN {}> could not
485be guaranteed (due to the errors), and since subsequent code likely
486depends on its correct operation, Perl just gave up.
68dc0745 487
c782d7ee 488=item \%d better written as $%d
6df41af2 489
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490(W syntax) Outside of patterns, backreferences live on as variables.
491The use of backslashes is grandfathered on the right-hand side of a
492substitution, but stylistically it's better to use the variable form
493because other Perl programmers will expect it, and it works better if
494there are more than 9 backreferences.
6df41af2 495
252aa082
JH
496=item Binary number > 0b11111111111111111111111111111111 non-portable
497
e476b1b5 498(W portable) The binary number you specified is larger than 2**32-1
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JH
499(4294967295) and therefore non-portable between systems. See
500L<perlport> for more on portability concerns.
252aa082 501
69282e91 502=item bind() on closed socket %s
a0d0e21e 503
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504(W closed) You tried to do a bind on a closed socket. Did you forget to
505check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 506
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JH
507=item binmode() on closed filehandle %s
508
509(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 510Check your control flow and number of arguments.
c289d2f7 511
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FC
512=item "\b{" is deprecated; use "\b\{" or "\b[{]" instead in regex; marked
513by S<<-- HERE> in m/%s/
f866a7cd 514
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515=item "\B{" is deprecated; use "\B\{" or "\B[{]" instead in regex; marked
516by S<<-- HERE> in m/%s/
f866a7cd 517
3c664d1a 518(D deprecated) Use of an unescaped "{" immediately following
a38411bc
FC
519a C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
520itself in a future release. You can either precede the brace
521with a backslash, or enclose it in square brackets; the latter
522is the way to go if the pattern delimiters are C<{}>.
f866a7cd 523
c5a0f51a
JH
524=item Bit vector size > 32 non-portable
525
e476b1b5 526(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 527
043c750c 528=item Bizarre copy of %s
4633a7c4 529
be771a83 530(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 531copiable.
4633a7c4 532
5a25739d
FC
533=item Bizarre SvTYPE [%d]
534
434f489b 535(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
536encountered an invalid data type.
537
f675dbe5
CB
538=item Buffer overflow in prime_env_iter: %s
539
be771a83
GS
540(W internal) A warning peculiar to VMS. While Perl was preparing to
541iterate over %ENV, it encountered a logical name or symbol definition
542which was too long, so it was truncated to the string shown.
f675dbe5 543
a0d0e21e
LW
544=item Callback called exit
545
4929bf7b 546(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
547exited by calling exit.
548
6df41af2 549=item %s() called too early to check prototype
f675dbe5 550
be771a83
GS
551(W prototype) You've called a function that has a prototype before the
552parser saw a definition or declaration for it, and Perl could not check
553that the call conforms to the prototype. You need to either add an
554early prototype declaration for the subroutine in question, or move the
555subroutine definition ahead of the call to get proper prototype
556checking. Alternatively, if you are certain that you're calling the
557function correctly, you may put an ampersand before the name to avoid
558the warning. See L<perlsub>.
f675dbe5 559
56feebad
FC
560=item Calling POSIX::%s() is deprecated
561
562(D deprecated) You called a function whose use is deprecated. See
563the function's name in L<POSIX> for details.
564
49704364 565=item Cannot compress integer in pack
0258719b
NC
566
567(F) An argument to pack("w",...) was too large to compress. The BER
568compressed integer format can only be used with positive integers, and you
569attempted to compress Infinity or a very large number (> 1e308).
570See L<perlfunc/pack>.
571
49704364 572=item Cannot compress negative numbers in pack
0258719b
NC
573
574(F) An argument to pack("w",...) was negative. The BER compressed integer
575format can only be used with positive integers. See L<perlfunc/pack>.
576
5c1f4d79
NC
577=item Cannot convert a reference to %s to typeglob
578
6903afa2
FC
579(F) You manipulated Perl's symbol table directly, stored a reference
580in it, then tried to access that symbol via conventional Perl syntax.
581The access triggers Perl to autovivify that typeglob, but it there is
582no legal conversion from that type of reference to a typeglob.
5c1f4d79 583
4040665a 584=item Cannot copy to %s
ba2fdce6
NC
585
586(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 587be directly assigned to.
ba2fdce6 588
b5d97229
RGS
589=item Cannot find encoding "%s"
590
591(S io) You tried to apply an encoding that did not exist to a filehandle,
592either with open() or binmode().
593
7355df7e
FC
594=item Cannot set tied @DB::args
595
596(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
597is not supported. (Before this error was added, it used to crash.)
598
ce65bc73
FC
599=item Cannot tie unreifiable array
600
601(P) You somehow managed to call C<tie> on an array that does not
602keep a reference count on its arguments and cannot be made to
603do so. Such arrays are not even supposed to be accessible to
604Perl code, but are only used internally.
605
96ebfdd7
RK
606=item Can only compress unsigned integers in pack
607
608(F) An argument to pack("w",...) was not an integer. The BER compressed
609integer format can only be used with positive integers, and you attempted
610to compress something else. See L<perlfunc/pack>.
611
a0d0e21e
LW
612=item Can't bless non-reference value
613
614(F) Only hard references may be blessed. This is how Perl "enforces"
615encapsulation of objects. See L<perlobj>.
616
dc57907a
RGS
617=item Can't "break" in a loop topicalizer
618
0d863452 619(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 620a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
621
622=item Can't "break" outside a given block
dc57907a 623
0d863452
RH
624(F) You called C<break>, but you're not inside a C<given> block.
625
6df41af2
GS
626=item Can't call method "%s" on an undefined value
627
628(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
629object reference or package name contains an undefined value. Something
630like this will reproduce the error:
6df41af2
GS
631
632 $BADREF = undef;
633 process $BADREF 1,2,3;
634 $BADREF->process(1,2,3);
635
a0d0e21e
LW
636=item Can't call method "%s" on unblessed reference
637
54310121 638(F) A method call must know in what package it's supposed to run. It
be771a83
GS
639ordinarily finds this out from the object reference you supply, but you
640didn't supply an object reference in this case. A reference isn't an
641object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
642
643=item Can't call method "%s" without a package or object reference
644
645(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
646object reference or package name contains an expression that returns a
647defined value which is neither an object reference nor a package name.
72b5445b
GS
648Something like this will reproduce the error:
649
650 $BADREF = 42;
651 process $BADREF 1,2,3;
652 $BADREF->process(1,2,3);
653
dfe378f1
FC
654=item Can't call mro_isa_changed_in() on anonymous symbol table
655
656(P) Perl got confused as to whether a hash was a plain hash or a
657symbol table hash when trying to update @ISA caches.
658
2bf7e7b2
FC
659=item Can't call mro_method_changed_in() on anonymous symbol table
660
661(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
662not attached to the symbol table.
663
a0d0e21e
LW
664=item Can't chdir to %s
665
f703fc96 666(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
667that you can chdir to, possibly because it doesn't exist.
668
0545a864 669=item Can't check filesystem of script "%s" for nosuid
104d25b7 670
be771a83
GS
671(P) For some reason you can't check the filesystem of the script for
672nosuid.
104d25b7 673
22e74366 674=item Can't coerce %s to %s in %s
a0d0e21e
LW
675
676(F) Certain types of SVs, in particular real symbol table entries
55497cff 677(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
678say things like:
679
680 *foo += 1;
681
682You CAN say
683
684 $foo = *foo;
685 $foo += 1;
686
687but then $foo no longer contains a glob.
688
0d863452 689=item Can't "continue" outside a when block
dc57907a 690
0d863452
RH
691(F) You called C<continue>, but you're not inside a C<when>
692or C<default> block.
693
a0d0e21e
LW
694=item Can't create pipe mailbox
695
be771a83
GS
696(P) An error peculiar to VMS. The process is suffering from exhausted
697quotas or other plumbing problems.
a0d0e21e 698
eb64745e
GS
699=item Can't declare %s in "%s"
700
30c282f6
NC
701(F) Only scalar, array, and hash variables may be declared as "my", "our" or
702"state" variables. They must have ordinary identifiers as names.
a0d0e21e 703
fc7debfb
FC
704=item Can't "default" outside a topicalizer
705
706(F) You have used a C<default> block that is neither inside a
707C<foreach> loop nor a C<given> block. (Note that this error is
708issued on exit from the C<default> block, so you won't get the
709error if you use an explicit C<continue>.)
710
6df41af2
GS
711=item Can't do inplace edit: %s is not a regular file
712
be771a83 713(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 714a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 715
a0d0e21e
LW
716=item Can't do inplace edit on %s: %s
717
be771a83
GS
718(S inplace) The creation of the new file failed for the indicated
719reason.
a0d0e21e 720
54310121 721=item Can't do inplace edit without backup
a0d0e21e 722
be771a83
GS
723(F) You're on a system such as MS-DOS that gets confused if you try
724reading from a deleted (but still opened) file. You have to say
725C<-i.bak>, or some such.
a0d0e21e 726
10f9c03d 727=item Can't do inplace edit: %s would not be unique
a0d0e21e 728
e476b1b5 729(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
730characters and Perl was unable to create a unique filename during
731inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 732
a0d0e21e
LW
733=item Can't do waitpid with flags
734
be771a83
GS
735(F) This machine doesn't have either waitpid() or wait4(), so only
736waitpid() without flags is emulated.
a0d0e21e 737
a0d0e21e
LW
738=item Can't emulate -%s on #! line
739
be771a83
GS
740(F) The #! line specifies a switch that doesn't make sense at this
741point. For example, it'd be kind of silly to put a B<-x> on the #!
742line.
a0d0e21e 743
1109a392
MHM
744=item Can't %s %s-endian %ss on this platform
745
746(F) Your platform's byte-order is neither big-endian nor little-endian,
747or it has a very strange pointer size. Packing and unpacking big- or
748little-endian floating point values and pointers may not be possible.
749See L<perlfunc/pack>.
750
a0d0e21e
LW
751=item Can't exec "%s": %s
752
d1be9408 753(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
754named program for the indicated reason. Typical reasons include: the
755permissions were wrong on the file, the file wasn't found in
756C<$ENV{PATH}>, the executable in question was compiled for another
757architecture, or the #! line in a script points to an interpreter that
758can't be run for similar reasons. (Or maybe your system doesn't support
759#! at all.)
a0d0e21e
LW
760
761=item Can't exec %s
762
be771a83
GS
763(F) Perl was trying to execute the indicated program for you because
764that's what the #! line said. If that's not what you wanted, you may
765need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
766
767=item Can't execute %s
768
be771a83
GS
769(F) You used the B<-S> switch, but the copies of the script to execute
770found in the PATH did not have correct permissions.
2a92aaa0 771
6df41af2 772=item Can't find an opnumber for "%s"
2a92aaa0 773
be771a83
GS
774(F) A string of a form C<CORE::word> was given to prototype(), but there
775is no builtin with the name C<word>.
6df41af2 776
56ca2fc0
JH
777=item Can't find %s character property "%s"
778
779(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 780could not be found. Maybe you misspelled the name of the property?
e1b711da 781See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 782for a complete list of available official properties.
56ca2fc0 783
6df41af2
GS
784=item Can't find label %s
785
be771a83
GS
786(F) You said to goto a label that isn't mentioned anywhere that it's
787possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
788
789=item Can't find %s on PATH
790
be771a83
GS
791(F) You used the B<-S> switch, but the script to execute could not be
792found in the PATH.
a0d0e21e 793
6df41af2 794=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 795
be771a83
GS
796(F) You used the B<-S> switch, but the script to execute could not be
797found in the PATH, or at least not with the correct permissions. The
798script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
799
800=item Can't find string terminator %s anywhere before EOF
801
be771a83
GS
802(F) Perl strings can stretch over multiple lines. This message means
803that the closing delimiter was omitted. Because bracketed quotes count
804nesting levels, the following is missing its final parenthesis:
a0d0e21e 805
fb73857a
PP
806 print q(The character '(' starts a side comment.);
807
97b3d10f 808If you're getting this error from a here-document, you may have
b6b8cb97
FC
809included unseen whitespace before or after your closing tag or there
810may not be a linebreak after it. A good programmer's editor will have
811a way to help you find these characters (or lack of characters). See
812L<perlop> for the full details on here-documents.
a0d0e21e 813
660a4616
ST
814=item Can't find Unicode property definition "%s"
815
5f8ad6b6
FC
816(F) You may have tried to use C<\p> which means a Unicode
817property (for example C<\p{Lu}> matches all uppercase
fa816bf3 818letters). If you did mean to use a Unicode property, see
e1b711da 819L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 820for a complete list of available properties. If you didn't
fa816bf3
FC
821mean to use a Unicode property, escape the C<\p>, either by
822C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 823until C<\E>).
660a4616 824
b3647a36 825=item Can't fork: %s
a0d0e21e 826
be771a83
GS
827(F) A fatal error occurred while trying to fork while opening a
828pipeline.
a0d0e21e 829
b3647a36
SR
830=item Can't fork, trying again in 5 seconds
831
c973c02e 832(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
833after five seconds.
834
748a9306
LW
835=item Can't get filespec - stale stat buffer?
836
be771a83
GS
837(S) A warning peculiar to VMS. This arises because of the difference
838between access checks under VMS and under the Unix model Perl assumes.
839Under VMS, access checks are done by filename, rather than by bits in
840the stat buffer, so that ACLs and other protections can be taken into
841account. Unfortunately, Perl assumes that the stat buffer contains all
842the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 843the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
844the device name and FID present in the stat buffer, but this works only
845if you haven't made a subsequent call to the CRTL stat() routine,
846because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
847appears, the name lookup failed, and the access-checking routine gave up
848and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
849routine knows about the Perl C<stat> operator and file tests, so you
850shouldn't ever see this warning in response to a Perl command; it arises
851only if some internal code takes stat buffers lightly.)
748a9306 852
a0d0e21e
LW
853=item Can't get pipe mailbox device name
854
be771a83
GS
855(P) An error peculiar to VMS. After creating a mailbox to act as a
856pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
857
858=item Can't get SYSGEN parameter value for MAXBUF
859
748a9306
LW
860(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
861mailbox buffers to be, and didn't get an answer.
a0d0e21e 862
6df41af2 863=item Can't "goto" into the middle of a foreach loop
a0d0e21e 864
be771a83
GS
865(F) A "goto" statement was executed to jump into the middle of a foreach
866loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
867
868=item Can't "goto" out of a pseudo block
869
be771a83
GS
870(F) A "goto" statement was executed to jump out of what might look like
871a block, except that it isn't a proper block. This usually occurs if
872you tried to jump out of a sort() block or subroutine, which is a no-no.
873See L<perlfunc/goto>.
a0d0e21e 874
5a25739d
FC
875=item Can't goto subroutine from an eval-%s
876
877(F) The "goto subroutine" call can't be used to jump out of an eval
878"string" or block.
879
9850bf21 880=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 881
9850bf21
RH
882(F) The "goto subroutine" call can't be used to jump out of the
883comparison sub for a sort(), or from a similar callback (such
884as the reduce() function in List::Util).
885
6df41af2
GS
886=item Can't goto subroutine outside a subroutine
887
be771a83
GS
888(F) The deeply magical "goto subroutine" call can only replace one
889subroutine call for another. It can't manufacture one out of whole
890cloth. In general you should be calling it out of only an AUTOLOAD
891routine anyway. See L<perlfunc/goto>.
6df41af2 892
0b5b802d
GS
893=item Can't ignore signal CHLD, forcing to default
894
be771a83
GS
895(W signal) Perl has detected that it is being run with the SIGCHLD
896signal (sometimes known as SIGCLD) disabled. Since disabling this
897signal will interfere with proper determination of exit status of child
898processes, Perl has reset the signal to its default value. This
899situation typically indicates that the parent program under which Perl
900may be running (e.g. cron) is being very careless.
0b5b802d 901
e2c0f81f
DG
902=item Can't kill a non-numeric process ID
903
904(F) Process identifiers must be (signed) integers. It is a fatal error to
905attempt to kill() an undefined, empty-string or otherwise non-numeric
906process identifier.
907
6df41af2 908=item Can't "last" outside a loop block
4633a7c4 909
6df41af2 910(F) A "last" statement was executed to break out of the current block,
be771a83
GS
911except that there's this itty bitty problem called there isn't a current
912block. Note that an "if" or "else" block doesn't count as a "loopish"
913block, as doesn't a block given to sort(), map() or grep(). You can
914usually double the curlies to get the same effect though, because the
915inner curlies will be considered a block that loops once. See
916L<perlfunc/last>.
4633a7c4 917
2c7d6b9c
RGS
918=item Can't linearize anonymous symbol table
919
920(F) Perl tried to calculate the method resolution order (MRO) of a
921package, but failed because the package stash has no name.
922
b8170e59
JB
923=item Can't load '%s' for module %s
924
6903afa2
FC
925(F) The module you tried to load failed to load a dynamic extension.
926This may either mean that you upgraded your version of perl to one
927that is incompatible with your old dynamic extensions (which is known
928to happen between major versions of perl), or (more likely) that your
929dynamic extension was built against an older version of the library
930that is installed on your system. You may need to rebuild your old
931dynamic extensions.
b8170e59 932
748a9306
LW
933=item Can't localize lexical variable %s
934
2ba9eb46 935(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
936lexical variable using "my" or "state". This is not allowed. If you
937want to localize a package variable of the same name, qualify it with
938the package name.
748a9306 939
6df41af2 940=item Can't localize through a reference
4727527e 941
6df41af2
GS
942(F) You said something like C<local $$ref>, which Perl can't currently
943handle, because when it goes to restore the old value of whatever $ref
be771a83 944pointed to after the scope of the local() is finished, it can't be sure
64977eb6 945that $ref will still be a reference.
4727527e 946
ea071790 947=item Can't locate %s
ec889f3a 948
fa816bf3
FC
949(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
950Perl looks for the file in all the locations mentioned in @INC, unless
951the file name included the full path to the file. Perhaps you need
952to set the PERL5LIB or PERL5OPT environment variable to say where the
953extra library is, or maybe the script needs to add the library name
be771a83
GS
954to @INC. Or maybe you just misspelled the name of the file. See
955L<perlfunc/require> and L<lib>.
a0d0e21e 956
6df41af2
GS
957=item Can't locate auto/%s.al in @INC
958
be771a83
GS
959(F) A function (or method) was called in a package which allows
960autoload, but there is no function to autoload. Most probable causes
961are a misprint in a function/method name or a failure to C<AutoSplit>
962the file, say, by doing C<make install>.
6df41af2 963
b8170e59
JB
964=item Can't locate loadable object for module %s in @INC
965
966(F) The module you loaded is trying to load an external library, like
d70d8e57 967for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
968unable to locate this library. See L<DynaLoader>.
969
a0d0e21e
LW
970=item Can't locate object method "%s" via package "%s"
971
972(F) You called a method correctly, and it correctly indicated a package
973functioning as a class, but that package doesn't define that particular
2ba9eb46 974method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
975
976=item Can't locate package %s for @%s::ISA
977
be771a83
GS
978(W syntax) The @ISA array contained the name of another package that
979doesn't seem to exist.
a0d0e21e 980
2f7da168
RK
981=item Can't locate PerlIO%s
982
983(F) You tried to use in open() a PerlIO layer that does not exist,
984e.g. open(FH, ">:nosuchlayer", "somefile").
985
f4ad53f4 986=item Can't make list assignment to %ENV on this system
3e3baf6d 987
be771a83
GS
988(F) List assignment to %ENV is not supported on some systems, notably
989VMS.
3e3baf6d 990
cd40cd58
NC
991=item Can't make loaded symbols global on this platform while loading %s
992
ff9c1ae8 993(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
994that symbols from the stated file are made available globally within the
995process, but that functionality is not available on this platform. Whilst
996the module likely will still work, this may prevent the perl interpreter
997from loading other XS-based extensions which need to link directly to
998functions defined in the C or XS code in the stated file.
999
a0d0e21e
LW
1000=item Can't modify %s in %s
1001
be771a83
GS
1002(F) You aren't allowed to assign to the item indicated, or otherwise try
1003to change it, such as with an auto-increment.
a0d0e21e 1004
54310121 1005=item Can't modify nonexistent substring
a0d0e21e
LW
1006
1007(P) The internal routine that does assignment to a substr() was handed
1008a NULL.
1009
6df41af2
GS
1010=item Can't modify non-lvalue subroutine call
1011
1012(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1013such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1014
5f05dabc 1015=item Can't msgrcv to read-only var
a0d0e21e 1016
5f05dabc 1017(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1018buffer.
1019
6df41af2
GS
1020=item Can't "next" outside a loop block
1021
1022(F) A "next" statement was executed to reiterate the current block, but
1023there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1024count as a "loopish" block, as doesn't a block given to sort(), map() or
1025grep(). You can usually double the curlies to get the same effect
1026though, because the inner curlies will be considered a block that loops
1027once. See L<perlfunc/next>.
6df41af2 1028
46fa9b26
FC
1029=item Can't open %s
1030
1031(F) You tried to run a perl built with MAD support with
1032the PERL_XMLDUMP environment variable set, but the file
1033named by that variable could not be opened.
1034
a0d0e21e
LW
1035=item Can't open %s: %s
1036
c47ff5f1 1037(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1038filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1039switches, or explicitly, failed for the indicated reason. Usually
1040this is because you don't have read permission for a file which
1041you named on the command line.
1042
1043(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1044your operating system's equivalent) could not be opened.
a0d0e21e 1045
9a869a14
RGS
1046=item Can't open a reference
1047
1048(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1049using the 3-arg open() syntax:
9a869a14
RGS
1050
1051 open FH, '>', $ref;
1052
1053but your version of perl is compiled without perlio, and this form of
1054open is not supported.
1055
a0d0e21e
LW
1056=item Can't open bidirectional pipe
1057
be771a83
GS
1058(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1059You can try any of several modules in the Perl library to do this, such
1060as IPC::Open2. Alternately, direct the pipe's output to a file using
1061">", and then read it in under a different file handle.
a0d0e21e 1062
748a9306
LW
1063=item Can't open error file %s as stderr
1064
be771a83
GS
1065(F) An error peculiar to VMS. Perl does its own command line
1066redirection, and couldn't open the file specified after '2>' or '2>>' on
1067the command line for writing.
748a9306
LW
1068
1069=item Can't open input file %s as stdin
1070
be771a83
GS
1071(F) An error peculiar to VMS. Perl does its own command line
1072redirection, and couldn't open the file specified after '<' on the
1073command line for reading.
748a9306
LW
1074
1075=item Can't open output file %s as stdout
1076
be771a83
GS
1077(F) An error peculiar to VMS. Perl does its own command line
1078redirection, and couldn't open the file specified after '>' or '>>' on
1079the command line for writing.
748a9306
LW
1080
1081=item Can't open output pipe (name: %s)
1082
be771a83
GS
1083(P) An error peculiar to VMS. Perl does its own command line
1084redirection, and couldn't open the pipe into which to send data destined
1085for stdout.
748a9306 1086
3b1cf97d 1087=item Can't open perl script "%s": %s
a0d0e21e
LW
1088
1089(F) The script you specified can't be opened for the indicated reason.
1090
fa3aa65a
JC
1091If you're debugging a script that uses #!, and normally relies on the
1092shell's $PATH search, the -S option causes perl to do that search, so
1093you don't have to type the path or C<`which $scriptname`>.
1094
6df41af2
GS
1095=item Can't read CRTL environ
1096
1097(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1098from the CRTL's internal environment array and discovered the array was
1099missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1100or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1101searched.
6df41af2 1102
6df41af2
GS
1103=item Can't "redo" outside a loop block
1104
1105(F) A "redo" statement was executed to restart the current block, but
1106there isn't a current block. Note that an "if" or "else" block doesn't
1107count as a "loopish" block, as doesn't a block given to sort(), map()
1108or grep(). You can usually double the curlies to get the same effect
1109though, because the inner curlies will be considered a block that
1110loops once. See L<perlfunc/redo>.
1111
64977eb6 1112=item Can't remove %s: %s, skipping file
10f9c03d 1113
be771a83
GS
1114(S inplace) You requested an inplace edit without creating a backup
1115file. Perl was unable to remove the original file to replace it with
1116the modified file. The file was left unmodified.
10f9c03d 1117
a0d0e21e
LW
1118=item Can't rename %s to %s: %s, skipping file
1119
e476b1b5 1120(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1121probably because you don't have write permission to the directory.
a0d0e21e 1122
748a9306
LW
1123=item Can't reopen input pipe (name: %s) in binary mode
1124
be771a83
GS
1125(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1126to reopen it to accept binary data. Alas, it failed.
748a9306 1127
4f12ec0e
FC
1128=item Can't reset %ENV on this system
1129
1130(F) You called C<reset('E')> or similar, which tried to reset
1131all variables in the current package beginning with "E". In
1132the main package, that includes %ENV. Resetting %ENV is not
1133supported on some systems, notably VMS.
1134
fe13d51d 1135=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1136
1fa582fa
FC
1137(F)(P) Error resolving overloading specified by a method name (as
1138opposed to a subroutine reference): no such method callable via the
1139package. If the method name is C<???>, this is an internal error.
6df41af2 1140
cd06dffe
GS
1141=item Can't return %s from lvalue subroutine
1142
be771a83
GS
1143(F) Perl detected an attempt to return illegal lvalues (such as
1144temporary or readonly values) from a subroutine used as an lvalue. This
1145is not allowed.
cd06dffe 1146
96ebfdd7
RK
1147=item Can't return outside a subroutine
1148
1149(F) The return statement was executed in mainline code, that is, where
1150there was no subroutine call to return out of. See L<perlsub>.
1151
78f9721b
SM
1152=item Can't return %s to lvalue scalar context
1153
6903afa2
FC
1154(F) You tried to return a complete array or hash from an lvalue
1155subroutine, but you called the subroutine in a way that made Perl
1156think you meant to return only one value. You probably meant to
1157write parentheses around the call to the subroutine, which tell
1158Perl that the call should be in list context.
78f9721b 1159
a0d0e21e
LW
1160=item Can't stat script "%s"
1161
be771a83
GS
1162(P) For some reason you can't fstat() the script even though you have it
1163open already. Bizarre.
a0d0e21e 1164
a0d0e21e
LW
1165=item Can't take log of %g
1166
fb73857a 1167(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1168negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1169standard with Perl, though, if you really want to do that for the
1170negative numbers.
a0d0e21e
LW
1171
1172=item Can't take sqrt of %g
1173
1174(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1175negative number. There's a Math::Complex package that comes standard
1176with Perl, though, if you really want to do that.
a0d0e21e
LW
1177
1178=item Can't undef active subroutine
1179
1180(F) You can't undefine a routine that's currently running. You can,
1181however, redefine it while it's running, and you can even undef the
1182redefined subroutine while the old routine is running. Go figure.
1183
c81225bc 1184=item Can't upgrade %s (%d) to %d
a0d0e21e 1185
be771a83
GS
1186(P) The internal sv_upgrade routine adds "members" to an SV, making it
1187into a more specialized kind of SV. The top several SV types are so
1188specialized, however, that they cannot be interconverted. This message
1189indicates that such a conversion was attempted.
a0d0e21e 1190
6651ba0b
FC
1191=item Can't use '%c' after -mname
1192
1193(F) You tried to call perl with the B<-m> switch, but you put something
1194other than "=" after the module name.
1195
1db89ea5
BS
1196=item Can't use anonymous symbol table for method lookup
1197
e27ad1f2 1198(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1199table that doesn't have a name. Symbol tables can become anonymous
1200for example by undefining stashes: C<undef %Some::Package::>.
1201
96ebfdd7
RK
1202=item Can't use an undefined value as %s reference
1203
1204(F) A value used as either a hard reference or a symbolic reference must
1205be a defined value. This helps to delurk some insidious errors.
1206
6df41af2
GS
1207=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1208
be771a83
GS
1209(F) Only hard references are allowed by "strict refs". Symbolic
1210references are disallowed. See L<perlref>.
6df41af2 1211
90b75b61 1212=item Can't use %! because Errno.pm is not available
1d2dff63 1213
20561843 1214(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1215Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1216provide symbolic names for C<$!> errno values.
1217
1109a392
MHM
1218=item Can't use both '<' and '>' after type '%c' in %s
1219
1220(F) A type cannot be forced to have both big-endian and little-endian
1221byte-order at the same time, so this combination of modifiers is not
1222allowed. See L<perlfunc/pack>.
1223
6df41af2
GS
1224=item Can't use %s for loop variable
1225
be771a83
GS
1226(F) Only a simple scalar variable may be used as a loop variable on a
1227foreach.
6df41af2 1228
aab6a793 1229=item Can't use global %s in "%s"
6df41af2 1230
be771a83
GS
1231(F) You tried to declare a magical variable as a lexical variable. This
1232is not allowed, because the magic can be tied to only one location
1233(namely the global variable) and it would be incredibly confusing to
1234have variables in your program that looked like magical variables but
6df41af2
GS
1235weren't.
1236
6d3b25aa
RGS
1237=item Can't use '%c' in a group with different byte-order in %s
1238
1239(F) You attempted to force a different byte-order on a type
1240that is already inside a group with a byte-order modifier.
1241For example you cannot force little-endianness on a type that
1242is inside a big-endian group.
1243
c07a80fd
PP
1244=item Can't use "my %s" in sort comparison
1245
1246(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1247You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1248and the variable had earlier been declared as a lexical variable.
1249Either qualify the sort variable with the package name, or rename the
1250lexical variable.
1251
a0d0e21e
LW
1252=item Can't use %s ref as %s ref
1253
1254(F) You've mixed up your reference types. You have to dereference a
1255reference of the type needed. You can use the ref() function to
1256test the type of the reference, if need be.
1257
748a9306 1258=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1259
5e634d20
FC
1260=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1261
b41bf23f
FC
1262(F) You've told Perl to dereference a string, something which
1263C<use strict> blocks to prevent it happening accidentally. See
1264L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1265in a double-quoted string immediately before interpolating a variable,
1266for example in C<"user @$twitter_id">, which says to treat the contents
1267of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1268symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1269
748a9306
LW
1270=item Can't use subscript on %s
1271
1272(F) The compiler tried to interpret a bracketed expression as a
1273subscript. But to the left of the brackets was an expression that
209e7cf1 1274didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1275
6df41af2
GS
1276=item Can't use \%c to mean $%c in expression
1277
75b44862
GS
1278(W syntax) In an ordinary expression, backslash is a unary operator that
1279creates a reference to its argument. The use of backslash to indicate a
1280backreference to a matched substring is valid only as part of a regular
be771a83
GS
1281expression pattern. Trying to do this in ordinary Perl code produces a
1282value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1283instead.
6df41af2 1284
810b8aa5
GS
1285=item Can't weaken a nonreference
1286
1287(F) You attempted to weaken something that was not a reference. Only
1288references can be weakened.
1289
fc7debfb
FC
1290=item Can't "when" outside a topicalizer
1291
1292(F) You have used a when() block that is neither inside a C<foreach>
1293loop nor a C<given> block. (Note that this error is issued on exit
1294from the C<when> block, so you won't get the error if the match fails,
1295or if you use an explicit C<continue>.)
1296
5f05dabc 1297=item Can't x= to read-only value
a0d0e21e 1298
be771a83
GS
1299(F) You tried to repeat a constant value (often the undefined value)
1300with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1301Perhaps you need to copy the value to a temporary, and repeat that.
1302
a04e6aad 1303=item Character following "\c" must be printable ASCII
f9d13529 1304
7357bd17 1305(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1306
727b6379 1307Note that ASCII characters that don't map to control characters are
7357bd17 1308discouraged, and will generate the warning (when enabled)
727b6379 1309L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1310
f337b084 1311=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1312
1313(W pack) You said
1314
1315 pack("C", $x)
1316
1317where $x is either less than 0 or more than 255; the C<"C"> format is
1318only for encoding native operating system characters (ASCII, EBCDIC,
1319and so on) and not for Unicode characters, so Perl behaved as if you meant
1320
1321 pack("C", $x & 255)
1322
1323If you actually want to pack Unicode codepoints, use the C<"U"> format
1324instead.
1325
f337b084 1326=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1327
1328(W pack) You said
1329
1330 pack("c", $x)
1331
1332where $x is either less than -128 or more than 127; the C<"c"> format
1333is only for encoding native operating system characters (ASCII, EBCDIC,
1334and so on) and not for Unicode characters, so Perl behaved as if you meant
1335
1336 pack("c", $x & 255);
1337
1338If you actually want to pack Unicode codepoints, use the C<"U"> format
1339instead.
1340
f337b084
TH
1341=item Character in '%c' format wrapped in unpack
1342
1343(W unpack) You tried something like
1344
1345 unpack("H", "\x{2a1}")
1346
1a147d38 1347where the format expects to process a byte (a character with a value
6903afa2
FC
1348below 256), but a higher value was provided instead. Perl uses the
1349value modulus 256 instead, as if you had provided:
f337b084
TH
1350
1351 unpack("H", "\x{a1}")
1352
5a25739d
FC
1353=item Character in 'W' format wrapped in pack
1354
1355(W pack) You said
1356
1357 pack("U0W", $x)
1358
1359where $x is either less than 0 or more than 255. However, C<U0>-mode
1360expects all values to fall in the interval [0, 255], so Perl behaved
1361as if you meant:
1362
1363 pack("U0W", $x & 255)
1364
f337b084
TH
1365=item Character(s) in '%c' format wrapped in pack
1366
1367(W pack) You tried something like
1368
1369 pack("u", "\x{1f3}b")
1370
1a147d38 1371where the format expects to process a sequence of bytes (character with a
6903afa2 1372value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1373uses the character values modulus 256 instead, as if you had provided:
1374
1375 pack("u", "\x{f3}b")
1376
1377=item Character(s) in '%c' format wrapped in unpack
1378
1379(W unpack) You tried something like
1380
1381 unpack("s", "\x{1f3}b")
1382
1a147d38 1383where the format expects to process a sequence of bytes (character with a
6903afa2 1384value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1385uses the character values modulus 256 instead, as if you had provided:
1386
1387 unpack("s", "\x{f3}b")
1388
f866a7cd
FC
1389=item "\c%c" is more clearly written simply as "%s"
1390
1391(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1392non-printable characters. You used it for a printable one, which is better
1393written as simply itself, perhaps preceded by a backslash for non-word
1394characters.
1395
6651ba0b
FC
1396=item Cloning substitution context is unimplemented
1397
1398(F) Creating a new thread inside the C<s///> operator is not supported.
1399
abc7ecad
SP
1400=item closedir() attempted on invalid dirhandle %s
1401
1402(W io) The dirhandle you tried to close is either closed or not really
1403a dirhandle. Check your control flow.
1404
5a25739d
FC
1405=item close() on unopened filehandle %s
1406
1407(W unopened) You tried to close a filehandle that was never opened.
1408
541ed3a9
FC
1409=item Closure prototype called
1410
1411(F) If a closure has attributes, the subroutine passed to an attribute
1412handler is the prototype that is cloned when a new closure is created.
1413This subroutine cannot be called.
1414
49704364
LW
1415=item Code missing after '/'
1416
6903afa2
FC
1417(F) You had a (sub-)template that ends with a '/'. There must be
1418another template code following the slash. See L<perlfunc/pack>.
49704364 1419
5a25739d
FC
1420=item Code point 0x%X is not Unicode, may not be portable
1421
2d88a86a 1422(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1423of U+10FFFF.
1424
1425Perl allows strings to contain a superset of Unicode code points, up
1426to the limit of what is storable in an unsigned integer on your system,
1427but these may not be accepted by other languages/systems. At one time,
1428it was legal in some standards to have code points up to 0x7FFF_FFFF,
1429but not higher. Code points above 0xFFFF_FFFF require larger than a
143032 bit word.
0876b9a0 1431
6df41af2
GS
1432=item %s: Command not found
1433
a892b81a 1434(A) You've accidentally run your script through B<csh> or another shell
f738a371 1435instead of Perl. Check the #! line, or manually feed your script
a892b81a 1436into Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1437
1438 #!/usr/bin/perl -w
6df41af2 1439
7a2e2cd6
PP
1440=item Compilation failed in require
1441
1442(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1443Perl uses this generic message when none of the errors that it
1444encountered were severe enough to halt compilation immediately.
7a2e2cd6 1445
c3464db5
DD
1446=item Complex regular subexpression recursion limit (%d) exceeded
1447
be771a83
GS
1448(W regexp) The regular expression engine uses recursion in complex
1449situations where back-tracking is required. Recursion depth is limited
1450to 32766, or perhaps less in architectures where the stack cannot grow
1451arbitrarily. ("Simple" and "medium" situations are handled without
1452recursion and are not subject to a limit.) Try shortening the string
1453under examination; looping in Perl code (e.g. with C<while>) rather than
1454in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1455that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1456on I<Mastering Regular Expressions>.)
c3464db5 1457
69282e91 1458=item connect() on closed socket %s
a0d0e21e 1459
be771a83
GS
1460(W closed) You tried to do a connect on a closed socket. Did you forget
1461to check the return value of your socket() call? See
1462L<perlfunc/connect>.
a0d0e21e 1463
e21e7c6a
FC
1464=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1465
1466(F) The subroutine registered to handle constant overloading
1467(see L<overload>) or a custom charnames handler (see
1468L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1469
1470=item Constant(%s): $^H{%s} is not defined
1471
1472(F) The parser found inconsistencies while attempting to define an
1473overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1474L<overload> pragma?
e21e7c6a 1475
779c5bc9
GS
1476=item Constant is not %s reference
1477
1478(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1479is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1480The message indicates the type of reference that was expected. This
be771a83 1481usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1482See L<perlsub/"Constant Functions"> and L<constant>.
1483
4cee8e80
CS
1484=item Constant subroutine %s redefined
1485
aeb94125
FC
1486(W redefine)(S) You redefined a subroutine which had previously
1487been eligible for inlining. See L<perlsub/"Constant Functions">
1488for commentary and workarounds.
4cee8e80 1489
9607fc9c
PP
1490=item Constant subroutine %s undefined
1491
be771a83
GS
1492(W misc) You undefined a subroutine which had previously been eligible
1493for inlining. See L<perlsub/"Constant Functions"> for commentary and
1494workarounds.
9607fc9c 1495
5a25739d
FC
1496=item Constant(%s) unknown
1497
1498(F) The parser found inconsistencies either while attempting
1499to define an overloaded constant, or when trying to find the
1500character name specified in the C<\N{...}> escape. Perhaps you
1501forgot to load the corresponding L<overload> pragma?.
1502
e7ea3e70
IZ
1503=item Copy method did not return a reference
1504
6903afa2 1505(F) The method which overloads "=" is buggy. See
13a2d996 1506L<overload/Copy Constructor>.
e7ea3e70 1507
4aaa4757
FC
1508=item &CORE::%s cannot be called directly
1509
1510(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1511with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1512in this package cannot yet be called that way, but must be
1513called as barewords. Something like this will work:
1514
1515 BEGIN { *shove = \&CORE::push; }
1516 shove @array, 1,2,3; # pushes on to @array
1517
6798c92b
GS
1518=item CORE::%s is not a keyword
1519
1520(F) The CORE:: namespace is reserved for Perl keywords.
1521
675fa9ff
FC
1522=item Corrupted regexp opcode %d > %d
1523
1524(P) This is either an error in Perl, or, if you're using
1525one, your L<custom regular expression engine|perlreapi>. If not the
1526latter, report the problem through the L<perlbug> utility.
1527
a0d0e21e
LW
1528=item corrupted regexp pointers
1529
1530(P) The regular expression engine got confused by what the regular
1531expression compiler gave it.
1532
1533=item corrupted regexp program
1534
be771a83
GS
1535(P) The regular expression engine got passed a regexp program without a
1536valid magic number.
a0d0e21e 1537
de42a5a9 1538=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1539
1540(P) The malloc package that comes with Perl had an internal failure.
1541
49704364
LW
1542=item Count after length/code in unpack
1543
1544(F) You had an unpack template indicating a counted-length string, but
1545you have also specified an explicit size for the string. See
1546L<perlfunc/pack>.
1547
f2cccb4c
KW
1548=for comment
1549The following are used in lib/diagnostics.t for testing two =items that
1550share the same description. Changes here need to be propagated to there
1551
6651ba0b
FC
1552=item Deep recursion on anonymous subroutine
1553
a0d0e21e
LW
1554=item Deep recursion on subroutine "%s"
1555
be771a83
GS
1556(W recursion) This subroutine has called itself (directly or indirectly)
1557100 times more than it has returned. This probably indicates an
1558infinite recursion, unless you're writing strange benchmark programs, in
1559which case it indicates something else.
a0d0e21e 1560
aad1d01f
NC
1561This threshold can be changed from 100, by recompiling the F<perl> binary,
1562setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1563
f10b0346 1564=item defined(@array) is deprecated
69794302 1565
be771a83
GS
1566(D deprecated) defined() is not usually useful on arrays because it
1567checks for an undefined I<scalar> value. If you want to see if the
64977eb6 1568array is empty, just use C<if (@array) { # not empty }> for example.
69794302 1569
f10b0346 1570=item defined(%hash) is deprecated
69794302 1571
f0ec9725
KR
1572(D deprecated) C<defined()> is not usually right on hashes and has been
1573discouraged since 5.004.
1574
1575Although C<defined %hash> is false on a plain not-yet-used hash, it
1576becomes true in several non-obvious circumstances, including iterators,
1577weak references, stash names, even remaining true after C<undef %hash>.
1578These things make C<defined %hash> fairly useless in practice.
1579
1580If a check for non-empty is what you wanted then just put it in boolean
1581context (see L<perldata/Scalar values>):
16546e45
KR
1582
1583 if (%hash) {
1584 # not empty
1585 }
1586
f0ec9725
KR
1587If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1588variable exists then that's never really been reliable, and isn't
1589a good way to enquire about the features of a package, or whether
1590it's loaded, etc.
1591
69794302 1592
e0e4a6e3
FC
1593=item (?(DEFINE)....) does not allow branches in regex; marked by
1594S<<-- HERE> in m/%s/
bcb95744 1595
6903afa2 1596(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1597most likely cause of this error is that you left out a parenthesis inside
1598of the C<....> part.
1599
9e3ec65c 1600The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1601discovered.
1602
62658f4d
PM
1603=item %s defines neither package nor VERSION--version check failed
1604
1605(F) You said something like "use Module 42" but in the Module file
1606there are neither package declarations nor a C<$VERSION>.
1607
36447869
FC
1608=item delete argument is index/value array slice, use array slice
1609
1610(F) You used index/value array slice syntax (C<%array[...]>) as
1611the argument to C<delete>. You probably meant C<@array[...]> with
1612an @ symbol instead.
1613
1614=item delete argument is key/value hash slice, use hash slice
1615
1616(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1617C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1618
0ffcbc25
FC
1619=item delete argument is not a HASH or ARRAY element or slice
1620
4a0af295 1621(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1622such as:
1623
1624 $foo{$bar}
1625 $ref->{"susie"}[12]
1626
1627or a hash or array slice, such as:
1628
1629 @foo[$bar, $baz, $xyzzy]
1630 @{$ref->[12]}{"susie", "queue"}
1631
fc36a67e
PP
1632=item Delimiter for here document is too long
1633
be771a83
GS
1634(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1635long for Perl to handle. You have to be seriously twisted to write code
1636that triggers this error.
fc36a67e 1637
6d3b25aa
RGS
1638=item Deprecated use of my() in false conditional
1639
fa816bf3
FC
1640(D deprecated) You used a declaration similar to C<my $x if 0>. There
1641has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1642not to be cleared at scope exit when its declaration includes a false
6903afa2 1643conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1644static variable. Since we intend to fix this bug, we don't want people
6903afa2 1645relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1646declaring the variable in a separate block outside the function, eg
36fb85f3 1647
6d3b25aa
RGS
1648 sub f { my $x if 0; return $x++ }
1649
1650becomes
1651
1652 { my $x; sub f { return $x++ } }
1653
ea9d9ebc 1654Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1655lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1656
1657 sub f { state $x; return $x++ }
1658
500ab966
RGS
1659=item DESTROY created new reference to dead object '%s'
1660
1661(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1662just being DESTROYed. Perl is confused, and prefers to abort rather
1663than to create a dangling reference.
500ab966 1664
3cdd684c
TP
1665=item Did not produce a valid header
1666
1667See Server error.
1668
6df41af2
GS
1669=item %s did not return a true value
1670
1671(F) A required (or used) file must return a true value to indicate that
1672it compiled correctly and ran its initialization code correctly. It's
1673traditional to end such a file with a "1;", though any true value would
1674do. See L<perlfunc/require>.
1675
cc507455 1676=item (Did you mean &%s instead?)
4633a7c4 1677
413ff9f6
FC
1678(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1679some such.
4633a7c4 1680
cc507455 1681=item (Did you mean "local" instead of "our"?)
33633739 1682
be771a83
GS
1683(W misc) Remember that "our" does not localize the declared global
1684variable. You have declared it again in the same lexical scope, which
1685seems superfluous.
33633739 1686
cc507455 1687=item (Did you mean $ or @ instead of %?)
a0d0e21e 1688
be771a83
GS
1689(W) You probably said %hash{$key} when you meant $hash{$key} or
1690@hash{@keys}. On the other hand, maybe you just meant %hash and got
1691carried away.
748a9306 1692
7e1af8bc 1693=item Died
5f05dabc
PP
1694
1695(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1696you called it with no args and C<$@> was empty.
5f05dabc 1697
3cdd684c
TP
1698=item Document contains no data
1699
1700See Server error.
1701
62658f4d
PM
1702=item %s does not define %s::VERSION--version check failed
1703
1704(F) You said something like "use Module 42" but the Module did not
943fc58e 1705define a C<$VERSION>.
62658f4d 1706
49704364
LW
1707=item '/' does not take a repeat count
1708
1709(F) You cannot put a repeat count of any kind right after the '/' code.
1710See L<perlfunc/pack>.
1711
95cb0d72
FC
1712=item Don't know how to get file name
1713
1714(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1715somehow called on another platform. This should not happen.
1716
4021c788 1717=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1718
1719(P) The internal handling of magical variables has been cursed.
1720
1721=item do_study: out of memory
1722
1723(P) This should have been caught by safemalloc() instead.
1724
6df41af2
GS
1725=item (Do you need to predeclare %s?)
1726
56da5a46
RGS
1727(S syntax) This is an educated guess made in conjunction with the message
1728"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1729name is being referenced that hasn't been declared yet. This may be
1730because of ordering problems in your file, or because of a missing
be771a83
GS
1731"sub", "package", "require", or "use" statement. If you're referencing
1732something that isn't defined yet, you don't actually have to define the
1733subroutine or package before the current location. You can use an empty
1734"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1735
ac206dc8
RGS
1736=item dump() better written as CORE::dump()
1737
1738(W misc) You used the obsolescent C<dump()> built-in function, without fully
1739qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1740
84d78eb7
YO
1741=item dump is not supported
1742
1743(F) Your machine doesn't support dump/undump.
1744
a0d0e21e
LW
1745=item Duplicate free() ignored
1746
be771a83
GS
1747(S malloc) An internal routine called free() on something that had
1748already been freed.
a0d0e21e 1749
1109a392
MHM
1750=item Duplicate modifier '%c' after '%c' in %s
1751
35f0cd76
FC
1752(W unpack) You have applied the same modifier more than once after a
1753type in a pack template. See L<perlfunc/pack>.
1109a392 1754
0953b66b
FC
1755=item each on reference is experimental
1756
0773cb3e
FC
1757(S experimental::autoderef) C<each> with a scalar argument is experimental
1758and may change or be removed in a future Perl version. If you want to
1759take the risk of using this feature, simply disable this warning:
0953b66b 1760
d401967c 1761 no warnings "experimental::autoderef";
0953b66b 1762
4633a7c4
LW
1763=item elseif should be elsif
1764
fa816bf3
FC
1765(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1766it's ugly. Your code will be interpreted as an attempt to call a method
1767named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1768unlikely to be what you want.
1769
e0e4a6e3 1770=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1771
af6f566e 1772(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1773described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1774a regular expression without specifying the property name.
ab13f0c7 1775
85ab1d1d 1776=item entering effective %s failed
5ff3f7a4 1777
85ab1d1d 1778(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1779effective uids or gids failed.
1780
c038024b
RGS
1781=item %ENV is aliased to %s
1782
1783(F) You're running under taint mode, and the C<%ENV> variable has been
1784aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1785program's environment. This is potentially insecure.
c038024b 1786
748a9306
LW
1787=item Error converting file specification %s
1788
5f05dabc 1789(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1790specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1791single form when it must operate on them directly. Either you've passed
1792an invalid file specification to Perl, or you've found a case the
1793conversion routines don't handle. Drat.
748a9306 1794
ad19ef22 1795=item Eval-group in insecure regular expression
e4d48cc9 1796
be771a83
GS
1797(F) Perl detected tainted data when trying to compile a regular
1798expression that contains the C<(?{ ... })> zero-width assertion, which
1799is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1800
ad19ef22 1801=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1802
be771a83
GS
1803(F) Perl tried to compile a regular expression containing the
1804C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1805pattern contains interpolated values. Since that is a security risk,
1806it is not allowed. If you insist, you may still do this by using the
1807C<re 'eval'> pragma or by explicitly building the pattern from an
1808interpolated string at run time and using that in an eval(). See
1809L<perlre/(?{ code })>.
e4d48cc9 1810
ad19ef22 1811=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1812
be771a83
GS
1813(F) A regular expression contained the C<(?{ ... })> zero-width
1814assertion, but that construct is only allowed when the C<use re 'eval'>
1815pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1816
e0e4a6e3
FC
1817=item EVAL without pos change exceeded limit in regex; marked by
1818S<<-- HERE> in m/%s/
1a147d38
YO
1819
1820(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1821any text. Restructure the pattern so that text is consumed.
1a147d38 1822
9e3ec65c 1823The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1824discovered.
1825
fc36a67e
PP
1826=item Excessively long <> operator
1827
1828(F) The contents of a <> operator may not exceed the maximum size of a
1829Perl identifier. If you're just trying to glob a long list of
1830filenames, try using the glob() operator, or put the filenames into a
1831variable and glob that.
1832
ed9aa3b7
SG
1833=item exec? I'm not *that* kind of operating system
1834
af8bb25a 1835(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1836OS. See L<perlport>.
ed9aa3b7 1837
fe13d51d 1838=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1839
1840(F) The final summary message when a Perl compilation fails.
1841
0ffcbc25
FC
1842=item exists argument is not a HASH or ARRAY element or a subroutine
1843
4a0af295 1844(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1845subroutine with an ampersand, such as:
1846
1847 $foo{$bar}
1848 $ref->{"susie"}[12]
1849 &do_something
1850
1851=item exists argument is not a subroutine name
1852
ccfc2567
FC
1853(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1854and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1855
a0d0e21e
LW
1856=item Exiting eval via %s
1857
be771a83
GS
1858(W exiting) You are exiting an eval by unconventional means, such as a
1859goto, or a loop control statement.
e476b1b5
GS
1860
1861=item Exiting format via %s
1862
9a2ff54b 1863(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1864goto, or a loop control statement.
a0d0e21e 1865
0a753a76
PP
1866=item Exiting pseudo-block via %s
1867
be771a83
GS
1868(W exiting) You are exiting a rather special block construct (like a
1869sort block or subroutine) by unconventional means, such as a goto, or a
1870loop control statement. See L<perlfunc/sort>.
0a753a76 1871
a0d0e21e
LW
1872=item Exiting subroutine via %s
1873
be771a83
GS
1874(W exiting) You are exiting a subroutine by unconventional means, such
1875as a goto, or a loop control statement.
a0d0e21e
LW
1876
1877=item Exiting substitution via %s
1878
be771a83
GS
1879(W exiting) You are exiting a substitution by unconventional means, such
1880as a return, a goto, or a loop control statement.
a0d0e21e 1881
e0e4a6e3 1882=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1883
675fa9ff 1884(F) You wrote something like
c608e803
KW
1885
1886 (?13
1887
1888to denote a capturing group of the form
1889L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1890but omitted the C<")">.
1891
e0e4a6e3 1892=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1893
8b6fbf55
FC
1894(F) The C<(?[...])> extended character class regular expression construct
1895only allows character classes (including character class escapes like
1896C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1897containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1898This allows a regular expression containing just C<(?[...])> to be
1899interpolated. If you see this error message, then you probably
1900have some other C<(?...)> construct inside your character class. See
1901L<perlrecharclass/Extended Bracketed Character Classes>.
1902
30d9c59b
Z
1903=item Experimental subroutine signatures not enabled
1904
1905(F) To use subroutine signatures, you must first enable them:
1906
caa35032 1907 no warnings "experimental::signatures";
30d9c59b
Z
1908 use feature "signatures";
1909 sub foo ($left, $right) { ... }
1910
6da34ecb
FC
1911=item Experimental "%s" subs not enabled
1912
1913(F) To use lexical subs, you must first enable them:
1914
1915 no warnings 'experimental::lexical_subs';
1916 use feature 'lexical_subs';
1917 my sub foo { ... }
1918
7b8d334a
GS
1919=item Explicit blessing to '' (assuming package main)
1920
be771a83
GS
1921(W misc) You are blessing a reference to a zero length string. This has
1922the effect of blessing the reference into the package main. This is
1923usually not what you want. Consider providing a default target package,
1924e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1925
6df41af2
GS
1926=item %s: Expression syntax
1927
be771a83
GS
1928(A) You've accidentally run your script through B<csh> instead of Perl.
1929Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1930
1931=item %s failed--call queue aborted
1932
3c10abe3
AG
1933(F) An untrapped exception was raised while executing a UNITCHECK,
1934CHECK, INIT, or END subroutine. Processing of the remainder of the
1935queue of such routines has been prematurely ended.
6df41af2 1936
e0e4a6e3 1937=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1938
98d31c73 1939(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1940character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1941in your false range is interpreted as a literal "-". In a C<(?[...])>
1942construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1943the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1944the problem was discovered. See L<perlre>.
73b437c8 1945
1b1ee2ef 1946=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1947
be771a83
GS
1948(P) An error peculiar to VMS. Something untoward happened in a VMS
1949system service or RTL routine; Perl's exit status should provide more
1950details. The filename in "at %s" and the line number in "line %d" tell
1951you which section of the Perl source code is distressed.
a0d0e21e
LW
1952
1953=item fcntl is not implemented
1954
1955(F) Your machine apparently doesn't implement fcntl(). What is this, a
1956PDP-11 or something?
1957
22846ab4
AB
1958=item FETCHSIZE returned a negative value
1959
1960(F) A tied array claimed to have a negative number of elements, which
1961is not possible.
1962
f337b084
TH
1963=item Field too wide in 'u' format in pack
1964
d8b5cc61 1965(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1966which can't encode values above 63. So there is no point in asking for
1967a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1968C<u63> as the format.
f337b084 1969
af8c498a 1970=item Filehandle %s opened only for input
a0d0e21e 1971
6c8d78fb
HS
1972(W io) You tried to write on a read-only filehandle. If you intended
1973it to be a read-write filehandle, you needed to open it with "+<" or
1974"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1975write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1976
af8c498a 1977=item Filehandle %s opened only for output
a0d0e21e 1978
6c8d78fb
HS
1979(W io) You tried to read from a filehandle opened only for writing, If
1980you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1981with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1982read from the file, use "<". See L<perlfunc/open>. Another possibility
1983is that you attempted to open filedescriptor 0 (also known as STDIN) for
1984output (maybe you closed STDIN earlier?).
97828cef
RGS
1985
1986=item Filehandle %s reopened as %s only for input
1987
1988(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 1989as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
1990previously.
1991
1992=item Filehandle STDIN reopened as %s only for output
1993
1994(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 1995as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
1996
1997=item Final $ should be \$ or $name
1998
1999(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2000a literal dollar sign, or was meant to introduce a variable name that
2001happens to be missing. So you have to put either the backslash or the
2002name.
a0d0e21e 2003
56e90b21
GS
2004=item flock() on closed filehandle %s
2005
be771a83 2006(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2007some time before now. Check your control flow. flock() operates on
be771a83
GS
2008filehandles. Are you attempting to call flock() on a dirhandle by the
2009same name?
56e90b21 2010
6df41af2
GS
2011=item Format not terminated
2012
2013(F) A format must be terminated by a line with a solitary dot. Perl got
2014to the end of your file without finding such a line.
2015
a0d0e21e
LW
2016=item Format %s redefined
2017
e476b1b5 2018(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2019
2020 {
271595cc 2021 no warnings 'redefine';
a0d0e21e
LW
2022 eval "format NAME =...";
2023 }
2024
a0d0e21e
LW
2025=item Found = in conditional, should be ==
2026
e476b1b5 2027(W syntax) You said
a0d0e21e
LW
2028
2029 if ($foo = 123)
2030
2031when you meant
2032
2033 if ($foo == 123)
2034
2035(or something like that).
2036
6df41af2
GS
2037=item %s found where operator expected
2038
56da5a46
RGS
2039(S syntax) The Perl lexer knows whether to expect a term or an operator.
2040If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2041operator, it gives you this warning. Usually it indicates that an
2042operator or delimiter was omitted, such as a semicolon.
6df41af2 2043
a0d0e21e
LW
2044=item gdbm store returned %d, errno %d, key "%s"
2045
2046(S) A warning from the GDBM_File extension that a store failed.
2047
2048=item gethostent not implemented
2049
2050(F) Your C library apparently doesn't implement gethostent(), probably
2051because if it did, it'd feel morally obligated to return every hostname
2052on the Internet.
2053
69282e91 2054=item get%sname() on closed socket %s
a0d0e21e 2055
be771a83
GS
2056(W closed) You tried to get a socket or peer socket name on a closed
2057socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2058
748a9306
LW
2059=item getpwnam returned invalid UIC %#o for user "%s"
2060
2061(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2062C<getpwnam> operator returned an invalid UIC.
2063
6df41af2
GS
2064=item getsockopt() on closed socket %s
2065
be771a83
GS
2066(W closed) You tried to get a socket option on a closed socket. Did you
2067forget to check the return value of your socket() call? See
6df41af2
GS
2068L<perlfunc/getsockopt>.
2069
0f539b13
BF
2070=item given is experimental
2071
675fa9ff
FC
2072(S experimental::smartmatch) C<given> depends on smartmatch, which
2073is experimental, so its behavior may change or even be removed
2074in any future release of perl. See the explanation under
2075L<perlsyn/Experimental Details on given and when>.
0f539b13 2076
6df41af2
GS
2077=item Global symbol "%s" requires explicit package name
2078
a4edf47d 2079(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2080that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2081declared beforehand using "our", or explicitly qualified to say
2082which package the global variable is in (using "::").
6df41af2 2083
e476b1b5
GS
2084=item glob failed (%s)
2085
5ead438e 2086(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2087for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2088pattern that caused the external program to fail and exit with a
be771a83 2089nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2090resulted in a coredump, this may also mean that your csh (C shell)
2091is broken. If so, you should change all of the csh-related variables
2092in config.sh: If you have tcsh, make the variables refer to it as
2093if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2094all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2095think csh is missing. In either case, after editing config.sh, run
75b44862 2096C<./Configure -S> and rebuild Perl.
e476b1b5 2097
a0d0e21e
LW
2098=item Glob not terminated
2099
2100(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2101a term, so it's looking for the corresponding right angle bracket, and
2102not finding it. Chances are you left some needed parentheses out
2103earlier in the line, and you really meant a "less than".
a0d0e21e 2104
b35b96b6
JH
2105=item gmtime(%f) failed
2106
2107(W overflow) You called C<gmtime> with a number that it could not handle:
2108too large, too small, or NaN. The returned value is C<undef>.
2109
bcd05b94 2110=item gmtime(%f) too large
8b56d6ff 2111
e9200be3 2112(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2113it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2114date. This warning is also triggered with NaN (the special
fc003d4b
MS
2115not-a-number value).
2116
bcd05b94 2117=item gmtime(%f) too small
fc003d4b 2118
e9200be3 2119(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2120it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2121
6df41af2 2122=item Got an error from DosAllocMem
a0d0e21e 2123
6df41af2
GS
2124(P) An error peculiar to OS/2. Most probably you're using an obsolete
2125version of Perl, and this should not happen anyway.
a0d0e21e
LW
2126
2127=item goto must have label
2128
2129(F) Unlike with "next" or "last", you're not allowed to goto an
2130unspecified destination. See L<perlfunc/goto>.
2131
6651ba0b
FC
2132=item Goto undefined subroutine%s
2133
2134(F) You tried to call a subroutine with C<goto &sub> syntax, but
2135the indicated subroutine hasn't been defined, or if it was, it
2136has since been undefined.
2137
6fbc9859 2138=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2139S<<-- HERE> in m/%s/
1f4f6bf1
YO
2140
2141(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2142they must start with a non-digit word character. A common cause of
2143this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2144
5a25739d
FC
2145=item ()-group starts with a count
2146
2147(F) A ()-group started with a count. A count is supposed to follow
2148something: a template character or a ()-group. See L<perlfunc/pack>.
2149
fe13d51d 2150=item %s had compilation errors.
6df41af2
GS
2151
2152(F) The final summary message when a C<perl -c> fails.
2153
a0d0e21e
LW
2154=item Had to create %s unexpectedly
2155
be771a83
GS
2156(S internal) A routine asked for a symbol from a symbol table that ought
2157to have existed already, but for some reason it didn't, and had to be
2158created on an emergency basis to prevent a core dump.
a0d0e21e 2159
6df41af2
GS
2160=item %s has too many errors
2161
2162(F) The parser has given up trying to parse the program after 10 errors.
2163Further error messages would likely be uninformative.
2164
252aa082
JH
2165=item Hexadecimal number > 0xffffffff non-portable
2166
e476b1b5 2167(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2168(4294967295) and therefore non-portable between systems. See
2169L<perlport> for more on portability concerns.
252aa082 2170
8903cb82
PP
2171=item Identifier too long
2172
2173(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2174about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2175names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2176of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2177
e0e4a6e3
FC
2178=item Ignoring zero length \N{} in character class in regex; marked by
2179S<<-- HERE> in m/%s/
fc8cd66c 2180
b5e3739b
FC
2181(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2182zero-length sequence. When such an escape is used in a character class
2183its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2184been used, and the correct charname handler is in scope.
2185
6df41af2 2186=item Illegal binary digit %s
f675dbe5 2187
6df41af2 2188(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2189
6df41af2 2190=item Illegal binary digit %s ignored
a0d0e21e 2191
be771a83
GS
2192(W digit) You may have tried to use a digit other than 0 or 1 in a
2193binary number. Interpretation of the binary number stopped before the
2194offending digit.
a0d0e21e 2195
6597eb22
FC
2196=item Illegal character after '_' in prototype for %s : %s
2197
e4d150f1
FC
2198(W illegalproto) An illegal character was found in a prototype
2199declaration. The '_' in a prototype must be followed by a ';',
2200indicating the rest of the parameters are optional, or one of '@'
2201or '%', since those two will accept 0 or more final parameters.
6597eb22 2202
78d0fecf 2203=item Illegal character \%o (carriage return)
4fdae800 2204
d5898338 2205(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2206would any other whitespace, which means you should never see this error
2207when Perl was built using standard options. For some reason, your
2208version of Perl appears to have been built without this support. Talk
2209to your Perl administrator.
4fdae800 2210
d37a9538
ST
2211=item Illegal character in prototype for %s : %s
2212
197afce1 2213(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2214Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2215Perhaps you were trying to write a subroutine signature but didn't enable
2216that feature first (C<use feature 'signatures'>), so your signature was
2217instead interpreted as a bad prototype.
d37a9538 2218
904d85c5
RGS
2219=item Illegal declaration of anonymous subroutine
2220
2221(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2222you must always specify a block of code. See L<perlsub>.
904d85c5 2223
8e742a20
MHM
2224=item Illegal declaration of subroutine %s
2225
6903afa2 2226(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2227
a0d0e21e
LW
2228=item Illegal division by zero
2229
be771a83
GS
2230(F) You tried to divide a number by 0. Either something was wrong in
2231your logic, or you need to put a conditional in to guard against
2232meaningless input.
a0d0e21e 2233
6df41af2
GS
2234=item Illegal hexadecimal digit %s ignored
2235
be771a83
GS
2236(W digit) You may have tried to use a character other than 0 - 9 or
2237A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2238number stopped before the illegal character.
6df41af2 2239
a0d0e21e
LW
2240=item Illegal modulus zero
2241
be771a83
GS
2242(F) You tried to divide a number by 0 to get the remainder. Most
2243numbers don't take to this kindly.
a0d0e21e 2244
6df41af2 2245=item Illegal number of bits in vec
399388f4 2246
6df41af2
GS
2247(F) The number of bits in vec() (the third argument) must be a power of
2248two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2249
2250=item Illegal octal digit %s
a0d0e21e 2251
d1be9408 2252(F) You used an 8 or 9 in an octal number.
a0d0e21e 2253
399388f4 2254=item Illegal octal digit %s ignored
748a9306 2255
d1be9408 2256(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2257Interpretation of the octal number stopped before the 8 or 9.
748a9306 2258
e0e4a6e3 2259=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2260
675fa9ff 2261(F) You wrote something like
c608e803
KW
2262
2263 (?+foo)
2264
2265The C<"+"> is valid only when followed by digits, indicating a
2266capturing group. See
2267L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2268
375ed12a
JH
2269=item Illegal suidscript
2270
2271(F) The script run under suidperl was somehow illegal.
2272
fe13d51d 2273=item Illegal switch in PERL5OPT: -%c
6ff81951 2274
6df41af2 2275(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2276following switches: B<-[CDIMUdmtw]>.
6ff81951 2277
6df41af2 2278=item Ill-formed CRTL environ value "%s"
81e118e0 2279
75b44862 2280(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2281internal environ array, and encountered an element without the C<=>
2282delimiter used to separate keys from values. The element is ignored.
09bef843 2283
6df41af2 2284=item Ill-formed message in prime_env_iter: |%s|
54310121 2285
be771a83
GS
2286(W internal) A warning peculiar to VMS. Perl tried to read a logical
2287name or CLI symbol definition when preparing to iterate over %ENV, and
2288didn't see the expected delimiter between key and value, so the line was
2289ignored.
54310121 2290
6df41af2 2291=item (in cleanup) %s
9607fc9c 2292
be771a83
GS
2293(W misc) This prefix usually indicates that a DESTROY() method raised
2294the indicated exception. Since destructors are usually called by the
2295system at arbitrary points during execution, and often a vast number of
2296times, the warning is issued only once for any number of failures that
2297would otherwise result in the same message being repeated.
6df41af2 2298
be771a83
GS
2299Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2300also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2301
e0e4a6e3
FC
2302=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2303in m/%s/
0d0b4b3b 2304
675fa9ff 2305(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2306expression inside the construct was completely empty, or if there are
2307too many or few operands for the number of operators. Perl is not smart
2308enough to give you a more precise indication as to what is wrong.
2309
6fbc9859
MH
2310=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2311parent '%s'
2c7d6b9c
RGS
2312
2313(F) The method resolution order (MRO) of the given class is not
2314C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2315documentation in L<mro> for more information.
2316
979699d9
JH
2317=item In EBCDIC the v-string components cannot exceed 2147483647
2318
2319(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2320Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2321encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2322
6a2ed79a 2323=item Infinite recursion in regex
1a147d38
YO
2324
2325(F) You used a pattern that references itself without consuming any input
6903afa2 2326text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2327either consume text or fail.
2328
6dbe9451
NC
2329=item Initialization of state variables in list context currently forbidden
2330
6903afa2
FC
2331(F) Currently the implementation of "state" only permits the
2332initialization of scalar variables in scalar context. Re-write
2333C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2334context. Constructions such as C<state (@a) = foo()> will be
2335supported in a future perl release.
6dbe9451 2336
2186f873
FC
2337=item %%s[%s] in scalar context better written as $%s[%s]
2338
2339(W syntax) In scalar context, you've used an array index/value slice
2340(indicated by %) to select a single element of an array. Generally
2341it's better to ask for a scalar value (indicated by $). The difference
2342is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2343returns and when evaluating its argument, while C<%foo[&bar]> provides
2344a list context to its subscript, which can do weird things if you're
2345expecting only one subscript. When called in list context, it also
2346returns the index (what C<&bar> returns) in addition to the value.
2347
2348=item %%s{%s} in scalar context better written as $%s{%s}
2349
2350(W syntax) In scalar context, you've used a hash key/value slice
2351(indicated by %) to select a single element of a hash. Generally it's
2352better to ask for a scalar value (indicated by $). The difference
2353is that C<$foo{&bar}> always behaves like a scalar, both in the value
2354it returns and when evaluating its argument, while C<@foo{&bar}> and
2355provides a list context to its subscript, which can do weird things
2356if you're expecting only one subscript. When called in list context,
2357it also returns the key in addition to the value.
2358
a0d0e21e
LW
2359=item Insecure dependency in %s
2360
8b1a09fc 2361(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2362The tainting mechanism is turned on when you're running setuid or
2363setgid, or when you specify B<-T> to turn it on explicitly. The
2364tainting mechanism labels all data that's derived directly or indirectly
2365from the user, who is considered to be unworthy of your trust. If any
2366such data is used in a "dangerous" operation, you get this error. See
2367L<perlsec> for more information.
a0d0e21e
LW
2368
2369=item Insecure directory in %s
2370
be771a83
GS
2371(F) You can't use system(), exec(), or a piped open in a setuid or
2372setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2373the world. Also, the PATH must not contain any relative directory.
2374See L<perlsec>.
a0d0e21e 2375
62f468fc 2376=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2377
2378(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2379setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2380C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2381supplied (or potentially supplied) by the user. The script must set
2382the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2383
0e9be77f
DM
2384=item Insecure user-defined property %s
2385
2386(F) Perl detected tainted data when trying to compile a regular
2387expression that contains a call to a user-defined character property
2388function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2389See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2390
cd209d9d 2391=item In '(?...)', the '(' and '?' must be adjacent in regex;
e0e4a6e3 2392marked by S<<-- HERE> in m/%s/
675fa9ff 2393
cd209d9d 2394(F) The two-character sequence C<"(?"> in
675fa9ff
FC
2395this context in a regular expression pattern should be an
2396indivisible token, with nothing intervening between the C<"(">
cd209d9d 2397and the C<"?">, but you separated them.
675fa9ff 2398
b9ef414d
FC
2399=item Integer overflow in format string for %s
2400
2401(F) The indexes and widths specified in the format string of C<printf()>
2402or C<sprintf()> are too large. The numbers must not overflow the size of
2403integers for your architecture.
2404
a7ae9550
GS
2405=item Integer overflow in %s number
2406
35928bc5 2407(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2408either as a literal or as an argument to hex() or oct() is too big for
2409your architecture, and has been converted to a floating point number.
2410On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2411representable without overflow is 0xFFFFFFFF, 037777777777, or
24120b11111111111111111111111111111111 respectively. Note that Perl
2413transparently promotes all numbers to a floating point representation
2414internally--subject to loss of precision errors in subsequent
2415operations.
bbce6d69 2416
fc89ca81
FC
2417=item Integer overflow in srand
2418
2419(S overflow) The number you have passed to srand is too big to fit
2420in your architecture's integer representation. The number has been
2421replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2422architectures). This means you may be getting less randomness than
2423you expect, because different random seeds above the maximum will
2424return the same sequence of random numbers.
2425
46314c13
JP
2426=item Integer overflow in version
2427
18da5252
FC
2428=item Integer overflow in version %d
2429
784d71ed
FC
2430(W overflow) Some portion of a version initialization is too large for
2431the size of integers for your architecture. This is not a warning
f084e84f 2432because there is no rational reason for a version to try and use an
784d71ed
FC
2433element larger than typically 2**32. This is usually caused by trying
2434to use some odd mathematical operation as a version, like 100/9.
46314c13 2435
e0e4a6e3 2436=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2437
2438(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2439The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2440discovered.
2441
748a9306
LW
2442=item Internal inconsistency in tracking vforks
2443
be771a83
GS
2444(S) A warning peculiar to VMS. Perl keeps track of the number of times
2445you've called C<fork> and C<exec>, to determine whether the current call
2446to C<exec> should affect the current script or a subprocess (see
2447L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2448Perl is making a guess and treating this C<exec> as a request to
2449terminate the Perl script and execute the specified command.
748a9306 2450
870978ae
FC
2451=item internal %<num>p might conflict with future printf extensions
2452
2453(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2454formatting follows a slightly different set of rules when called from
2455C or XS code. Specifically, formats consisting of digits followed
2456by "p" (e.g., "%7p") are reserved for future use. If you see this
2457message, then an XS module tried to call that routine with one such
2458reserved format.
2459
e0e4a6e3 2460=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2461
fa816bf3 2462(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2463S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2464discovered.
a0d0e21e 2465
6df41af2
GS
2466=item %s (...) interpreted as function
2467
75b44862 2468(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2469followed by parentheses turns into a function, with all the list
64977eb6 2470operators arguments found inside the parentheses. See
13a2d996 2471L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2472
09bef843
SB
2473=item Invalid %s attribute: %s
2474
a4a4c9e2 2475(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2476by Perl or by a user-supplied handler. See L<attributes>.
2477
2478=item Invalid %s attributes: %s
2479
a4a4c9e2 2480(F) The indicated attributes for a subroutine or variable were not
be771a83 2481recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2482
e0e4a6e3
FC
2483=item Invalid character in charnames alias definition; marked by
2484S<<-- HERE> in '%s
225fb84f
KW
2485
2486(F) You tried to create a custom alias for a character name, with
2487the C<:alias> option to C<use charnames> and the specified character in
2488the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2489
c8028aa6
TC
2490=item Invalid \0 character in %s for %s: %s\0%s
2491
fa3234e3
FC
2492(W syscalls) Embedded \0 characters in pathnames or other system call
2493arguments produce a warning as of 5.20. The parts after the \0 were
2494formerly ignored by system calls.
c8028aa6 2495
e0e4a6e3 2496=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2497
2498(F) Only certain characters are valid for character names. The
2499indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2500
c635e13b
PP
2501=item Invalid conversion in %s: "%s"
2502
be771a83
GS
2503(W printf) Perl does not understand the given format conversion. See
2504L<perlfunc/sprintf>.
c635e13b 2505
e0e4a6e3
FC
2506=item Invalid escape in the specified encoding in regex; marked by
2507S<<-- HERE> in m/%s/
9e08bc66 2508
98d31c73 2509(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2510didn't correspond to a single character through the conversion
2511from the encoding specified by the encoding pragma.
98d31c73
FC
2512The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2513instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2514The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2515escape was discovered.
2516
8149aa9f
FC
2517=item Invalid hexadecimal number in \N{U+...}
2518
e0e4a6e3
FC
2519=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2520S<<-- HERE> in m/%s/
aec0ef10 2521
8149aa9f 2522(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2523number. Either it is empty, or you tried to use a character other than
25240 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2525
6651ba0b
FC
2526=item Invalid module name %s with -%c option: contains single ':'
2527
2528(F) The module argument to perl's B<-m> and B<-M> command-line options
2529cannot contain single colons in the module name, but only in the
2530arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2531B<-MFoo:Bar=baz> is not.
2532
2c7d6b9c
RGS
2533=item Invalid mro name: '%s'
2534
162a3e34
FC
2535(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2536where C<foo> is not a valid method resolution order (MRO). Currently,
2537the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2538a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2539
40e4140b
FC
2540=item Invalid negative number (%s) in chr
2541
2542(W utf8) You passed a negative number to C<chr>. Negative numbers are
2543not valid characters numbers, so it return the Unicode replacement
2544character (U+FFFD).
2545
6651ba0b
FC
2546=item invalid option -D%c, use -D'' to see choices
2547
8ff21bfe
FC
2548(S debugging) Perl was called with invalid debugger flags. Call perl
2549with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2550See also L<perlrun/-Dletters>.
6651ba0b 2551
e0e4a6e3 2552=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2553
2554(F) The range specified in a character class had a minimum character
7253e4e3
RK
2555greater than the maximum character. One possibility is that you forgot the
2556C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2557up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2558problem was discovered. See L<perlre>.
6df41af2 2559
d1573ac7 2560=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2561
2562(F) The range specified in the tr/// or y/// operator had a minimum
2563character greater than the maximum character. See L<perlop>.
2564
09bef843
SB
2565=item Invalid separator character %s in attribute list
2566
0120eecf 2567(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2568elements of an attribute list. If the previous attribute had a
2569parenthesised parameter list, perhaps that list was terminated too soon.
2570See L<attributes>.
09bef843 2571
b4581f09
JH
2572=item Invalid separator character %s in PerlIO layer specification %s
2573
2bfc5f71
FC
2574(W layer) When pushing layers onto the Perl I/O system, something other
2575than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2576If the previous attribute had a parenthesised parameter list, perhaps that
2577list was terminated too soon.
2578
2c86d456
DG
2579=item Invalid strict version format (%s)
2580
fa816bf3 2581(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2582A "strict" version number is a positive decimal number (integer or
2583decimal-fraction) without exponentiation or else a dotted-decimal
2584v-string with a leading 'v' character and at least three components.
a6485a24 2585The parenthesized text indicates which criteria were not met.
2c86d456
DG
2586See the L<version> module for more details on allowed version formats.
2587
49704364 2588=item Invalid type '%s' in %s
96e4d5b1 2589
49704364
LW
2590(F) The given character is not a valid pack or unpack type.
2591See L<perlfunc/pack>.
6728c851 2592
49704364 2593(W) The given character is not a valid pack or unpack type but used to be
75b44862 2594silently ignored.
96e4d5b1 2595
2c86d456
DG
2596=item Invalid version format (%s)
2597
fa816bf3 2598(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2599A "lax" version number is a positive decimal number (integer or
2600decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2601v-string. If the v-string has fewer than three components, it
2602must have a leading 'v' character. Otherwise, the leading 'v' is
2603optional. Both decimal and dotted-decimal versions may have a
2604trailing "alpha" component separated by an underscore character
2605after a fractional or dotted-decimal component. The parenthesized
2606text indicates which criteria were not met. See the L<version> module
2607for more details on allowed version formats.
46314c13 2608
798ae1b7
DG
2609=item Invalid version object
2610
fa816bf3
FC
2611(F) The internal structure of the version object was invalid.
2612Perhaps the internals were modified directly in some way or
2613an arbitrary reference was blessed into the "version" class.
798ae1b7 2614
cd209d9d 2615=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2616marked by S<<-- HERE> in m/%s/
675fa9ff 2617
cd209d9d 2618(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2619this context in a regular expression pattern should be an
2620indivisible token, with nothing intervening between the C<"(">
cd209d9d 2621and the C<"*">, but you separated them.
675fa9ff 2622
a0d0e21e
LW
2623=item ioctl is not implemented
2624
2625(F) Your machine apparently doesn't implement ioctl(), which is pretty
2626strange for a machine that supports C.
2627
c289d2f7
JH
2628=item ioctl() on unopened %s
2629
2630(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2631Check your control flow and number of arguments.
c289d2f7 2632
fe13d51d 2633=item IO layers (like '%s') unavailable
363c40c4
SB
2634
2635(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2636you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2637with 'useperlio'.
2638
80cbd5ad
JH
2639=item IO::Socket::atmark not implemented on this architecture
2640
2641(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2642neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2643
4f650b80 2644=item $* is no longer supported
b4581f09 2645
4f650b80 2646(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2647perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2648previous versions of perl the use of C<$*> enabled or disabled multi-line
2649matching within a string.
4fd19576
B
2650
2651Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2652modifiers. You can enable C</m> for a lexical scope (even a whole file)
2653with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2654then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2655
8ae1fe26
RGS
2656=item $# is no longer supported
2657
a58ac25e 2658(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2659perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2660should use the printf/sprintf functions instead.
8ae1fe26 2661
ccf3535a 2662=item '%s' is not a code reference
6ad11d81 2663
6903afa2
FC
2664(W overload) The second (fourth, sixth, ...) argument of
2665overload::constant needs to be a code reference. Either
2666an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2667
ccf3535a 2668=item '%s' is not an overloadable type
6ad11d81 2669
04a80ee0
RGS
2670(W overload) You tried to overload a constant type the overload package is
2671unaware of.
6ad11d81 2672
5a25739d
FC
2673=item -i used with no filenames on the command line, reading from STDIN
2674
2675(S inplace) The C<-i> option was passed on the command line, indicating
2676that the script is intended to edit files in place, but no files were
2677given. This is usually a mistake, since editing STDIN in place doesn't
2678make sense, and can be confusing because it can make perl look like
2679it is hanging when it is really just trying to read from STDIN. You
2680should either pass a filename to edit, or remove C<-i> from the command
2681line. See L<perlrun> for more details.
2682
aec0ef10 2683=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2684
2685(P) The regular expression parser is confused.
2686
0953b66b
FC
2687=item keys on reference is experimental
2688
0773cb3e
FC
2689(S experimental::autoderef) C<keys> with a scalar argument is experimental
2690and may change or be removed in a future Perl version. If you want to
2691take the risk of using this feature, simply disable this warning:
0953b66b 2692
d401967c 2693 no warnings "experimental::autoderef";
0953b66b 2694
a0d0e21e
LW
2695=item Label not found for "last %s"
2696
be771a83
GS
2697(F) You named a loop to break out of, but you're not currently in a loop
2698of that name, not even if you count where you were called from. See
2699L<perlfunc/last>.
a0d0e21e
LW
2700
2701=item Label not found for "next %s"
2702
2703(F) You named a loop to continue, but you're not currently in a loop of
2704that name, not even if you count where you were called from. See
2705L<perlfunc/last>.
2706
2707=item Label not found for "redo %s"
2708
2709(F) You named a loop to restart, but you're not currently in a loop of
2710that name, not even if you count where you were called from. See
2711L<perlfunc/last>.
2712
85ab1d1d 2713=item leaving effective %s failed
5ff3f7a4 2714
85ab1d1d 2715(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2716effective uids or gids failed.
2717
49704364
LW
2718=item length/code after end of string in unpack
2719
d7f8936a 2720(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2721length/code combination tried to obtain more data. This results in
2722an undefined value for the length. See L<perlfunc/pack>.
49704364 2723
25e26107 2724=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2725
0d46a4e7
FC
2726(W syntax) You used length() on either an array or a hash when you
2727probably wanted a count of the items.
e508c8a4
MH
2728
2729Array size can be obtained by doing:
2730
2731 scalar(@array);
2732
2733The number of items in a hash can be obtained by doing:
2734
2735 scalar(keys %hash);
2736
f0e67a1d
Z
2737=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2738
d4fe7078
RS
2739(F) An extension is attempting to insert text into the current parse
2740(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2741couldn't be part of the current input. This is an inherent pitfall
2742of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2743it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2744
2745=item Lexing code internal error (%s)
2746
2747(F) Lexing code supplied by an extension violated the lexer's API in a
2748detectable way.
2749
69282e91 2750=item listen() on closed socket %s
a0d0e21e 2751
be771a83
GS
2752(W closed) You tried to do a listen on a closed socket. Did you forget
2753to check the return value of your socket() call? See
2754L<perlfunc/listen>.
a0d0e21e 2755
6651ba0b
FC
2756=item List form of piped open not implemented
2757
2758(F) On some platforms, notably Windows, the three-or-more-arguments
2759form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2760Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2761
b35b96b6
JH
2762=item localtime(%f) failed
2763
2764(W overflow) You called C<localtime> with a number that it could not handle:
2765too large, too small, or NaN. The returned value is C<undef>.
2766
bcd05b94 2767=item localtime(%f) too large
8b56d6ff 2768
e9200be3 2769(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2770than it can reliably handle and C<localtime> probably returned the
6903afa2 2771wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2772not-a-number value).
2773
bcd05b94 2774=item localtime(%f) too small
fc003d4b 2775
e9200be3 2776(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2777than it can reliably handle and C<localtime> probably returned the
e7a1a147 2778wrong date.
8b56d6ff 2779
58e23c8d 2780=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2781
2782(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2783handle. This restriction may be eased in a future release.
2e50fd82 2784
b88df990
NC
2785=item Lost precision when %s %f by 1
2786
e63e8a91
FC
2787(W imprecision) The value you attempted to increment or decrement by one
2788is too large for the underlying floating point representation to store
2789accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2790warning because it has already switched from integers to floating point
2791when values are too large for integers, and now even floating point is
2792insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2793
93fad930 2794=item lstat() on filehandle%s
2f7da168
RK
2795
2796(W io) You tried to do an lstat on a filehandle. What did you mean
2797by that? lstat() makes sense only on filenames. (Perl did a fstat()
2798instead on the filehandle.)
2799
345d70e3 2800=item lvalue attribute %s already-defined subroutine
bb3abb05 2801
345d70e3
FC
2802(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2803attribute on or off on a Perl subroutine that is already defined
2804does not always work properly. It may or may not do what you
2805want, depending on what code is inside the subroutine, with exact
2806details subject to change between Perl versions. Only do this
2807if you really know what you are doing.
bb3abb05 2808
885ef6f5
GG
2809=item lvalue attribute ignored after the subroutine has been defined
2810
345d70e3
FC
2811(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2812subroutine an lvalue subroutine after it has been defined is
2813not permitted. To make the subroutine an lvalue subroutine,
2814add the lvalue attribute to the definition, or put the C<sub
2815foo :lvalue;> declaration before the definition.
2816
2817See also L<attributes.pm|attributes>.
885ef6f5 2818
6f1b3ab0
FC
2819=item Magical list constants are not supported
2820
2821(F) You assigned a magical array to a stash element, and then tried
2822to use the subroutine from the same slot. You are asking Perl to do
2823something it cannot do, details subject to change between Perl versions.
2824
2db62bbc 2825=item Malformed integer in [] in pack
49704364 2826
2db62bbc 2827(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2828are permitted. See L<perlfunc/pack>.
2829
2830=item Malformed integer in [] in unpack
2831
2db62bbc 2832(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2833are permitted. See L<perlfunc/pack>.
2834
6df41af2
GS
2835=item Malformed PERLLIB_PREFIX
2836
2837(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2838
2839 prefix1;prefix2
2840
2841or
6df41af2
GS
2842 prefix1 prefix2
2843
be771a83
GS
2844with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2845a builtin library search path, prefix2 is substituted. The error may
2846appear if components are not found, or are too long. See
fecfaeb8 2847"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2848
2f758a16
ST
2849=item Malformed prototype for %s: %s
2850
d37a9538
ST
2851(F) You tried to use a function with a malformed prototype. The
2852syntax of function prototypes is given a brief compile-time check for
2853obvious errors like invalid characters. A more rigorous check is run
2854when the function is called.
30d9c59b
Z
2855Perhaps the function's author was trying to write a subroutine signature
2856but didn't enable that feature first (C<use feature 'signatures'>),
2857so the signature was instead interpreted as a bad prototype.
2f758a16 2858
ba210ebe
JH
2859=item Malformed UTF-8 character (%s)
2860
4d6f11e5 2861(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2862encoding rules, even though it had the UTF8 flag on.
ba210ebe 2863
2575c402
JW
2864One possible cause is that you set the UTF8 flag yourself for data that
2865you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28668-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2867
2868If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2869sequences are handled gracefully, but if you use C<:utf8>, the flag is
2870set without validating the data, possibly resulting in this error
2871message.
2872
2873See also L<Encode/"Handling Malformed Data">.
901b21bf 2874
107160e2
KW
2875=item Malformed UTF-8 character immediately after '%s'
2876
2877(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2878encoding rules. The message prints out the properly encoded characters
2879just before the first bad one. If C<utf8> warnings are enabled, a
2880warning is generated that gives more details about the type of
2881malformation.
2882
bde9e88d 2883=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2884
2885(F) The charnames handler returned malformed UTF-8.
2886
4a5d3a93
FC
2887=item Malformed UTF-8 string in '%c' format in unpack
2888
2889(F) You tried to unpack something that didn't comply with UTF-8 encoding
2890rules and perl was unable to guess how to make more progress.
2891
f337b084
TH
2892=item Malformed UTF-8 string in pack
2893
2894(F) You tried to pack something that didn't comply with UTF-8 encoding
2895rules and perl was unable to guess how to make more progress.
2896
2897=item Malformed UTF-8 string in unpack
2898
2899(F) You tried to unpack something that didn't comply with UTF-8 encoding
2900rules and perl was unable to guess how to make more progress.
2901
4a5d3a93 2902=item Malformed UTF-16 surrogate
f337b084 2903
4a5d3a93
FC
2904(F) Perl thought it was reading UTF-16 encoded character data but while
2905doing it Perl met a malformed Unicode surrogate.
2906
30d9c59b
Z
2907=item Mandatory parameter follows optional parameter
2908
2909(F) In a subroutine signature, you wrote something like "$a = undef,
2910$b", making an earlier parameter optional and a later one mandatory.
2911Parameters are filled from left to right, so it's impossible for the
2912caller to omit an earlier one and pass a later one. If you want to act
2913as if the parameters are filled from right to left, declare the rightmost
2914optional and then shuffle the parameters around in the subroutine's body.
2915
2d88a86a
KW
2916=item Matched non-Unicode code point 0x%X against Unicode property; may
2917not be portable
2918
2919(S non_unicode) Perl allows strings to contain a superset of
2920Unicode code points; each code point may be as large as what is storable
2921in an unsigned integer on your system, but these may not be accepted by
2922other languages/systems. This message occurs when you matched a string
2923containing such a code point against a regular expression pattern, and
2924the code point was matched against a Unicode property, C<\p{...}> or
2925C<\P{...}>. Unicode properties are only defined on Unicode code points,
2926so the result of this match is undefined by Unicode, but Perl (starting
2927in v5.20) treats non-Unicode code points as if they were typical
2928unassigned Unicode ones, and matched this one accordingly. Whether a
2929given property matches these code points or not is specified in
2930L<perluniprops/Properties accessible through \p{} and \P{}>.
2931
2932This message is suppressed (unless it has been made fatal) if it is
2933immaterial to the results of the match if the code point is Unicode or
2934not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2935the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2936Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2937every code point except these 22.)
2938
2939Getting this message indicates that the outcome of the match arguably
2940should have been the opposite of what actually happened. If you think
2941that is the case, you may wish to make the C<non_unicode> warnings
2942category fatal; if you agree with Perl's decision, you may wish to turn
2943off this category.
2944
2945See L<perlunicode/Beyond Unicode code points> for more information.
2946
e0e4a6e3
FC
2947=item %s matches null string many times in regex; marked by S<<-- HERE> in
2948m/%s/
4a5d3a93
FC
2949
2950(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2951regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2952shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2953See L<perlre>.
f337b084 2954
de42a5a9 2955=item Maximal count of pending signals (%u) exceeded
2563cec5 2956
6903afa2 2957(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2958usually indicates that your operating system tried to deliver signals
2959too fast (with a very high priority), starving the perl process from
2960resources it would need to reach a point where it can process signals
6903afa2 2961safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2962
25f58aea
PN
2963=item "%s" may clash with future reserved word
2964
2965(W) This warning may be due to running a perl5 script through a perl4
2966interpreter, especially if the word that is being warned about is
2967"use" or "my".
2968
0d2487cd 2969=item '%' may not be used in pack
6df41af2
GS
2970
2971(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2972checksumming process loses information, and you can't go the other way.
2973See L<perlfunc/unpack>.
6df41af2 2974
a0d0e21e
LW
2975=item Method for operation %s not found in package %s during blessing
2976
2977(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2978doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2979
3cdd684c
TP
2980=item Method %s not permitted
2981
2982See Server error.
2983
a0d0e21e
LW
2984=item Might be a runaway multi-line %s string starting on line %d
2985
2986(S) An advisory indicating that the previous error may have been caused
2987by a missing delimiter on a string or pattern, because it eventually
2988ended earlier on the current line.
2989
2990=item Misplaced _ in number
2991
d4ced10d
JH
2992(W syntax) An underscore (underbar) in a numeric constant did not
2993separate two digits.
a0d0e21e 2994
7baa4690
HS
2995=item Missing argument in %s
2996
2997(W uninitialized) A printf-type format required more arguments than were
2998supplied.
2999
9e81e6a1
RGS
3000=item Missing argument to -%c
3001
3002(F) The argument to the indicated command line switch must follow
3003immediately after the switch, without intervening spaces.
3004
ff3f963a 3005=item Missing braces on \N{}
423cee85 3006
e0e4a6e3 3007=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3008
4a2d328f 3009(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3010double-quotish context. This can also happen when there is a space
3011(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3012This modifier does not change the requirement that the brace immediately
3013follow the C<\N>.
423cee85 3014
f0a2b745
KW
3015=item Missing braces on \o{}
3016
3017(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3018
a0d0e21e
LW
3019=item Missing comma after first argument to %s function
3020
3021(F) While certain functions allow you to specify a filehandle or an
3022"indirect object" before the argument list, this ain't one of them.
3023
06eaf0bc
GS
3024=item Missing command in piped open
3025
be771a83
GS
3026(W pipe) You used the C<open(FH, "| command")> or
3027C<open(FH, "command |")> construction, but the command was missing or
3028blank.
06eaf0bc 3029
961ce445
RGS
3030=item Missing control char name in \c
3031
3032(F) A double-quoted string ended with "\c", without the required control
3033character name.
3034
591f5ca2
FC
3035=item Missing ']' in prototype for %s : %s
3036
bfe11873 3037(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3038
8767b1ab 3039=item Missing name in "%s sub"
6df41af2 3040
87444db5 3041(F) The syntax for lexically scoped subroutines requires that
be771a83 3042they have a name with which they can be found.
6df41af2
GS
3043
3044=item Missing $ on loop variable
3045
be771a83
GS
3046(F) Apparently you've been programming in B<csh> too much. Variables
3047are always mentioned with the $ in Perl, unlike in the shells, where it
3048can vary from one line to the next.
6df41af2 3049
cc507455 3050=item (Missing operator before %s?)
748a9306 3051
56da5a46
RGS
3052(S syntax) This is an educated guess made in conjunction with the message
3053"%s found where operator expected". Often the missing operator is a comma.
748a9306 3054
e0e4a6e3 3055=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3056
ff3f963a
KW
3057(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3058
4a68bf9d 3059=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3060
d32207c9
FC
3061(F) C<\N> has two meanings.
3062
3063The traditional one has it followed by a name enclosed in braces,
3064meaning the character (or sequence of characters) given by that
fa816bf3 3065name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3066double-quoted strings and regular expression patterns. In patterns,
3067it doesn't have the meaning an unescaped C<*> does.
3068
3069Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3070in patterns, namely to match a non-newline character. (This is short
3071for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3072
3073This can lead to some ambiguities. When C<\N> is not followed immediately
3074by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3075form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3076means to match the given quantity of non-newlines (in these examples,
30773; and 5 or more, respectively). In all other case, where there is a
3078C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3079
3080However, if there is no matching C<}>, Perl doesn't know if it was
3081mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3082If you meant the former, add the right brace; if you meant the latter,
3083escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3084
d98d5fff 3085=item Missing right curly or square bracket
a0d0e21e 3086
be771a83
GS
3087(F) The lexer counted more opening curly or square brackets than closing
3088ones. As a general rule, you'll find it's missing near the place you
3089were last editing.
a0d0e21e 3090
6df41af2
GS
3091=item (Missing semicolon on previous line?)
3092
56da5a46
RGS
3093(S syntax) This is an educated guess made in conjunction with the message
3094"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3095the previous line just because you saw this message.
3096
a0d0e21e
LW
3097=item Modification of a read-only value attempted
3098
3099(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3100constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3101catches that. But an easy way to do the same thing is:
3102
3103 sub mod { $_[0] = 1 }
3104 mod(2);
3105
3106Another way is to assign to a substr() that's off the end of the string.
3107
c5674021
PDF
3108Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3109is aliased to a constant in the look I<LIST>:
3110
b7e4ecc1
FC
3111 $x = 1;
3112 foreach my $n ($x, 2) {
3113 $n *= 2; # modifies the $x, but fails on attempt to
3114 } # modify the 2
c5674021 3115
7a4340ed 3116=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3117
3118(F) You tried to make an array value spring into existence, and the
3119subscript was probably negative, even counting from end of the array
3120backwards.
3121
7a4340ed 3122=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3123
be771a83
GS
3124(P) You tried to make a hash value spring into existence, and it
3125couldn't be created for some peculiar reason.
a0d0e21e
LW
3126
3127=item Module name must be constant
3128
3129(F) Only a bare module name is allowed as the first argument to a "use".
3130
be98fb35 3131=item Module name required with -%c option
6df41af2 3132
be98fb35
GS
3133(F) The C<-M> or C<-m> options say that Perl should load some module, but
3134you omitted the name of the module. Consult L<perlrun> for full details
3135about C<-M> and C<-m>.
6df41af2 3136
fe13d51d 3137=item More than one argument to '%s' open
ed9aa3b7 3138
6903afa2 3139(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3140can happen if you are trying to open a pipe to a command that takes a
3141list of arguments, but have forgotten to specify a piped open mode.
3142See L<perlfunc/open> for details.
3143
85396b18
FC
3144=item mprotect for COW string %p %u failed with %d
3145
3146(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3147L<perlguts/"Copy on Write">), but a shared string buffer
3148could not be made read-only.
3149
92951bce
FC
3150=item mprotect for %p %u failed with %d
3151
85396b18
FC
3152(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3153but an op tree could not be made read-only.
3154
3155=item mprotect RW for COW string %p %u failed with %d
3156
3157(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3158L<perlguts/"Copy on Write">), but a read-only shared string
3159buffer could not be made mutable.
3160
92951bce
FC
3161=item mprotect RW for %p %u failed with %d
3162
3163(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3164L<perlhacktips>), but a read-only op tree could not be made
3165mutable before freeing the ops.
92951bce 3166
a0d0e21e
LW
3167=item msg%s not implemented
3168
3169(F) You don't have System V message IPC on your system.
3170
3171=item Multidimensional syntax %s not supported
3172
75b44862
GS
3173(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3174They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3175
49704364 3176=item '/' must follow a numeric type in unpack
6df41af2 3177
49704364
LW
3178(F) You had an unpack template that contained a '/', but this did not
3179follow some unpack specification producing a numeric value.
3180See L<perlfunc/pack>.
6df41af2
GS
3181
3182=item "my sub" not yet implemented
3183
be771a83
GS
3184(F) Lexically scoped subroutines are not yet implemented. Don't try
3185that yet.
6df41af2 3186
5a25739d
FC
3187=item "my %s" used in sort comparison
3188
3189(W syntax) The package variables $a and $b are used for sort comparisons.
3190You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3191sort comparison block, and the variable had earlier been declared as a
3192lexical variable. Either qualify the sort variable with the package
3193name, or rename the lexical variable.
3194
fd1b7234 3195=item "my" variable %s can't be in a package
6df41af2 3196
be771a83
GS
3197(F) Lexically scoped variables aren't in a package, so it doesn't make
3198sense to try to declare one with a package qualifier on the front. Use
3199local() if you want to localize a package variable.
09bef843 3200
8149aa9f
FC
3201=item Name "%s::%s" used only once: possible typo
3202
c59aba6c
FC
3203(W once) Typographical errors often show up as unique variable
3204names. If you had a good reason for having a unique name, then
3205just mention it again somehow to suppress the message. The C<our>
08a33b6b 3206declaration is also provided for this purpose.
c59aba6c 3207
08a33b6b
AP
3208NOTE: This warning detects package symbols that have been used only
3209once. This means lexical variables will never trigger this warning.
3210It also means that all of the package variables $c, @c, %c, as well
3211as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3212format) are considered the same; if a program uses $c only once
3213but also uses any of the others it will not trigger this warning.
3214Symbols beginning with an underscore and symbols using special
3215identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3216
e0e4a6e3 3217=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3218
3219(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3220exactly 3 digits long. This helps catch some ambiguities. If your
3221constant is too short, add leading zeros, like
3222
3223 (?[ [ \078 ] ]) # Syntax error!
3224 (?[ [ \0078 ] ]) # Works
3225 (?[ [ \007 8 ] ]) # Clearer
3226
3227The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3228need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3229two separate things, you need to separate them:
0d0b4b3b
KW
3230
3231 (?[ [ \7776 ] ]) # Syntax error!
3232 (?[ [ \o{7776} ] ]) # One meaning
3233 (?[ [ \777 6 ] ]) # Another meaning
3234 (?[ [ \777 \006 ] ]) # Still another
3235
49704364
LW
3236=item Negative '/' count in unpack
3237
3238(F) The length count obtained from a length/code unpack operation was
3239negative. See L<perlfunc/pack>.
3240
a0d0e21e
LW
3241=item Negative length
3242
be771a83
GS
3243(F) You tried to do a read/write/send/recv operation with a buffer
3244length that is less than 0. This is difficult to imagine.
a0d0e21e 3245
ed9aa3b7
SG
3246=item Negative offset to vec in lvalue context
3247
3248(F) When C<vec> is called in an lvalue context, the second argument must be
3249greater than or equal to zero.
3250
e0e4a6e3 3251=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3252
6903afa2 3253(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3254So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3255whereabouts in the regular expression the problem was discovered.
a0d0e21e 3256
7253e4e3 3257Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3258C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3259
6df41af2 3260=item %s never introduced
a0d0e21e 3261
be771a83
GS
3262(S internal) The symbol in question was declared but somehow went out of
3263scope before it could possibly have been used.
a0d0e21e 3264
2c7d6b9c
RGS
3265=item next::method/next::can/maybe::next::method cannot find enclosing method
3266
3267(F) C<next::method> needs to be called within the context of a
3268real method in a real package, and it could not find such a context.
3269See L<mro>.
3270
5a25739d 3271=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3272marked by S<<-- HERE> in m/%s/
5a25739d 3273
32a77fbe
FC
3274(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3275bracketed character class, for the same reason that C<.> in a character
3276class loses its specialness: it matches almost everything, which is
3277probably not what you want.
5a25739d 3278
0b4ce96d 3279=item \N{} in character class restricted to one character in regex; marked
e0e4a6e3 3280by S<<-- HERE> in m/%s/
0b4ce96d
FC
3281
3282(F) Named Unicode character escapes C<(\N{...})> may return a
3283multi-character sequence. Such an escape may not be used in
3284a character class, because character classes always match one
3285character of input. Check that the correct escape has been used,
e0e4a6e3 3286and the correct charname handler is in scope. The S<<-- HERE> shows
0b4ce96d
FC
3287whereabouts in the regular expression the problem was discovered.
3288
e0e4a6e3
FC
3289=item \N{NAME} must be resolved by the lexer in regex; marked by
3290S<<-- HERE> in m/%s/
5a25739d
FC
3291
3292(F) When compiling a regex pattern, an unresolved named character or
3293sequence was encountered. This can happen in any of several ways that
3294bypass the lexer, such as using single-quotish context, or an extra
3295backslash in double-quotish:
3296
3297 $re = '\N{SPACE}'; # Wrong!
3298 $re = "\\N