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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
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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
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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
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420=item Bad realloc() ignored
421
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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
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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:
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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
a0d0e21e
LW
1029=item Can't open %s: %s
1030
c47ff5f1 1031(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1032filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1033switches, or explicitly, failed for the indicated reason. Usually
1034this is because you don't have read permission for a file which
1035you named on the command line.
1036
1037(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1038your operating system's equivalent) could not be opened.
a0d0e21e 1039
9a869a14
RGS
1040=item Can't open a reference
1041
1042(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1043using the 3-arg open() syntax:
9a869a14
RGS
1044
1045 open FH, '>', $ref;
1046
1047but your version of perl is compiled without perlio, and this form of
1048open is not supported.
1049
a0d0e21e
LW
1050=item Can't open bidirectional pipe
1051
be771a83
GS
1052(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1053You can try any of several modules in the Perl library to do this, such
1054as IPC::Open2. Alternately, direct the pipe's output to a file using
1055">", and then read it in under a different file handle.
a0d0e21e 1056
748a9306
LW
1057=item Can't open error file %s as stderr
1058
be771a83
GS
1059(F) An error peculiar to VMS. Perl does its own command line
1060redirection, and couldn't open the file specified after '2>' or '2>>' on
1061the command line for writing.
748a9306
LW
1062
1063=item Can't open input file %s as stdin
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 '<' on the
1067command line for reading.
748a9306
LW
1068
1069=item Can't open output file %s as stdout
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 '>' or '>>' on
1073the command line for writing.
748a9306
LW
1074
1075=item Can't open output pipe (name: %s)
1076
be771a83
GS
1077(P) An error peculiar to VMS. Perl does its own command line
1078redirection, and couldn't open the pipe into which to send data destined
1079for stdout.
748a9306 1080
3b1cf97d 1081=item Can't open perl script "%s": %s
a0d0e21e
LW
1082
1083(F) The script you specified can't be opened for the indicated reason.
1084
fa3aa65a
JC
1085If you're debugging a script that uses #!, and normally relies on the
1086shell's $PATH search, the -S option causes perl to do that search, so
1087you don't have to type the path or C<`which $scriptname`>.
1088
6df41af2
GS
1089=item Can't read CRTL environ
1090
1091(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1092from the CRTL's internal environment array and discovered the array was
1093missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1094or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1095searched.
6df41af2 1096
6df41af2
GS
1097=item Can't "redo" outside a loop block
1098
1099(F) A "redo" statement was executed to restart the current block, but
1100there isn't a current block. Note that an "if" or "else" block doesn't
1101count as a "loopish" block, as doesn't a block given to sort(), map()
1102or grep(). You can usually double the curlies to get the same effect
1103though, because the inner curlies will be considered a block that
1104loops once. See L<perlfunc/redo>.
1105
64977eb6 1106=item Can't remove %s: %s, skipping file
10f9c03d 1107
be771a83
GS
1108(S inplace) You requested an inplace edit without creating a backup
1109file. Perl was unable to remove the original file to replace it with
1110the modified file. The file was left unmodified.
10f9c03d 1111
a0d0e21e
LW
1112=item Can't rename %s to %s: %s, skipping file
1113
e476b1b5 1114(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1115probably because you don't have write permission to the directory.
a0d0e21e 1116
748a9306
LW
1117=item Can't reopen input pipe (name: %s) in binary mode
1118
be771a83
GS
1119(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1120to reopen it to accept binary data. Alas, it failed.
748a9306 1121
4f12ec0e
FC
1122=item Can't reset %ENV on this system
1123
1124(F) You called C<reset('E')> or similar, which tried to reset
1125all variables in the current package beginning with "E". In
1126the main package, that includes %ENV. Resetting %ENV is not
1127supported on some systems, notably VMS.
1128
fe13d51d 1129=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1130
1fa582fa
FC
1131(F)(P) Error resolving overloading specified by a method name (as
1132opposed to a subroutine reference): no such method callable via the
1133package. If the method name is C<???>, this is an internal error.
6df41af2 1134
cd06dffe
GS
1135=item Can't return %s from lvalue subroutine
1136
be771a83
GS
1137(F) Perl detected an attempt to return illegal lvalues (such as
1138temporary or readonly values) from a subroutine used as an lvalue. This
1139is not allowed.
cd06dffe 1140
96ebfdd7
RK
1141=item Can't return outside a subroutine
1142
1143(F) The return statement was executed in mainline code, that is, where
1144there was no subroutine call to return out of. See L<perlsub>.
1145
78f9721b
SM
1146=item Can't return %s to lvalue scalar context
1147
6903afa2
FC
1148(F) You tried to return a complete array or hash from an lvalue
1149subroutine, but you called the subroutine in a way that made Perl
1150think you meant to return only one value. You probably meant to
1151write parentheses around the call to the subroutine, which tell
1152Perl that the call should be in list context.
78f9721b 1153
a0d0e21e
LW
1154=item Can't stat script "%s"
1155
be771a83
GS
1156(P) For some reason you can't fstat() the script even though you have it
1157open already. Bizarre.
a0d0e21e 1158
a0d0e21e
LW
1159=item Can't take log of %g
1160
fb73857a 1161(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1162negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1163standard with Perl, though, if you really want to do that for the
1164negative numbers.
a0d0e21e
LW
1165
1166=item Can't take sqrt of %g
1167
1168(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1169negative number. There's a Math::Complex package that comes standard
1170with Perl, though, if you really want to do that.
a0d0e21e
LW
1171
1172=item Can't undef active subroutine
1173
1174(F) You can't undefine a routine that's currently running. You can,
1175however, redefine it while it's running, and you can even undef the
1176redefined subroutine while the old routine is running. Go figure.
1177
c81225bc 1178=item Can't upgrade %s (%d) to %d
a0d0e21e 1179
be771a83
GS
1180(P) The internal sv_upgrade routine adds "members" to an SV, making it
1181into a more specialized kind of SV. The top several SV types are so
1182specialized, however, that they cannot be interconverted. This message
1183indicates that such a conversion was attempted.
a0d0e21e 1184
6651ba0b
FC
1185=item Can't use '%c' after -mname
1186
1187(F) You tried to call perl with the B<-m> switch, but you put something
1188other than "=" after the module name.
1189
1f1ec7b5
KW
1190=item Can't use a hash as a reference
1191
1192(F) You tried to use a hash as a reference, as in
1193C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
1194used to allow this syntax, but shouldn't have.
1195
1196=item Can't use an array as a reference
1197
1198(F) You tried to use an array as a reference, as in
1199C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
1200allow this syntax, but shouldn't have.
1201
1db89ea5
BS
1202=item Can't use anonymous symbol table for method lookup
1203
e27ad1f2 1204(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1205table that doesn't have a name. Symbol tables can become anonymous
1206for example by undefining stashes: C<undef %Some::Package::>.
1207
96ebfdd7
RK
1208=item Can't use an undefined value as %s reference
1209
1210(F) A value used as either a hard reference or a symbolic reference must
1211be a defined value. This helps to delurk some insidious errors.
1212
6df41af2
GS
1213=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1214
be771a83
GS
1215(F) Only hard references are allowed by "strict refs". Symbolic
1216references are disallowed. See L<perlref>.
6df41af2 1217
90b75b61 1218=item Can't use %! because Errno.pm is not available
1d2dff63 1219
20561843 1220(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1221Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1222provide symbolic names for C<$!> errno values.
1223
1109a392
MHM
1224=item Can't use both '<' and '>' after type '%c' in %s
1225
1226(F) A type cannot be forced to have both big-endian and little-endian
1227byte-order at the same time, so this combination of modifiers is not
1228allowed. See L<perlfunc/pack>.
1229
6df41af2
GS
1230=item Can't use %s for loop variable
1231
be771a83
GS
1232(F) Only a simple scalar variable may be used as a loop variable on a
1233foreach.
6df41af2 1234
aab6a793 1235=item Can't use global %s in "%s"
6df41af2 1236
be771a83
GS
1237(F) You tried to declare a magical variable as a lexical variable. This
1238is not allowed, because the magic can be tied to only one location
1239(namely the global variable) and it would be incredibly confusing to
1240have variables in your program that looked like magical variables but
6df41af2
GS
1241weren't.
1242
6d3b25aa
RGS
1243=item Can't use '%c' in a group with different byte-order in %s
1244
1245(F) You attempted to force a different byte-order on a type
1246that is already inside a group with a byte-order modifier.
1247For example you cannot force little-endianness on a type that
1248is inside a big-endian group.
1249
c07a80fd
PP
1250=item Can't use "my %s" in sort comparison
1251
1252(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1253You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1254and the variable had earlier been declared as a lexical variable.
1255Either qualify the sort variable with the package name, or rename the
1256lexical variable.
1257
a0d0e21e
LW
1258=item Can't use %s ref as %s ref
1259
1260(F) You've mixed up your reference types. You have to dereference a
1261reference of the type needed. You can use the ref() function to
1262test the type of the reference, if need be.
1263
748a9306 1264=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1265
5e634d20
FC
1266=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1267
b41bf23f
FC
1268(F) You've told Perl to dereference a string, something which
1269C<use strict> blocks to prevent it happening accidentally. See
1270L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1271in a double-quoted string immediately before interpolating a variable,
1272for example in C<"user @$twitter_id">, which says to treat the contents
1273of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1274symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1275
748a9306
LW
1276=item Can't use subscript on %s
1277
1278(F) The compiler tried to interpret a bracketed expression as a
1279subscript. But to the left of the brackets was an expression that
209e7cf1 1280didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1281
6df41af2
GS
1282=item Can't use \%c to mean $%c in expression
1283
75b44862
GS
1284(W syntax) In an ordinary expression, backslash is a unary operator that
1285creates a reference to its argument. The use of backslash to indicate a
1286backreference to a matched substring is valid only as part of a regular
be771a83
GS
1287expression pattern. Trying to do this in ordinary Perl code produces a
1288value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1289instead.
6df41af2 1290
810b8aa5
GS
1291=item Can't weaken a nonreference
1292
1293(F) You attempted to weaken something that was not a reference. Only
1294references can be weakened.
1295
fc7debfb
FC
1296=item Can't "when" outside a topicalizer
1297
1298(F) You have used a when() block that is neither inside a C<foreach>
1299loop nor a C<given> block. (Note that this error is issued on exit
1300from the C<when> block, so you won't get the error if the match fails,
1301or if you use an explicit C<continue>.)
1302
5f05dabc 1303=item Can't x= to read-only value
a0d0e21e 1304
be771a83
GS
1305(F) You tried to repeat a constant value (often the undefined value)
1306with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1307Perhaps you need to copy the value to a temporary, and repeat that.
1308
a04e6aad 1309=item Character following "\c" must be printable ASCII
f9d13529 1310
7357bd17 1311(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1312
727b6379 1313Note that ASCII characters that don't map to control characters are
7357bd17 1314discouraged, and will generate the warning (when enabled)
727b6379 1315L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1316
f337b084 1317=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1318
1319(W pack) You said
1320
1321 pack("C", $x)
1322
1323where $x is either less than 0 or more than 255; the C<"C"> format is
1324only for encoding native operating system characters (ASCII, EBCDIC,
1325and so on) and not for Unicode characters, so Perl behaved as if you meant
1326
1327 pack("C", $x & 255)
1328
1329If you actually want to pack Unicode codepoints, use the C<"U"> format
1330instead.
1331
f337b084 1332=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1333
1334(W pack) You said
1335
1336 pack("c", $x)
1337
1338where $x is either less than -128 or more than 127; the C<"c"> format
1339is only for encoding native operating system characters (ASCII, EBCDIC,
1340and so on) and not for Unicode characters, so Perl behaved as if you meant
1341
1342 pack("c", $x & 255);
1343
1344If you actually want to pack Unicode codepoints, use the C<"U"> format
1345instead.
1346
f337b084
TH
1347=item Character in '%c' format wrapped in unpack
1348
1349(W unpack) You tried something like
1350
1351 unpack("H", "\x{2a1}")
1352
1a147d38 1353where the format expects to process a byte (a character with a value
6903afa2
FC
1354below 256), but a higher value was provided instead. Perl uses the
1355value modulus 256 instead, as if you had provided:
f337b084
TH
1356
1357 unpack("H", "\x{a1}")
1358
5a25739d
FC
1359=item Character in 'W' format wrapped in pack
1360
1361(W pack) You said
1362
1363 pack("U0W", $x)
1364
1365where $x is either less than 0 or more than 255. However, C<U0>-mode
1366expects all values to fall in the interval [0, 255], so Perl behaved
1367as if you meant:
1368
1369 pack("U0W", $x & 255)
1370
f337b084
TH
1371=item Character(s) in '%c' format wrapped in pack
1372
1373(W pack) You tried something like
1374
1375 pack("u", "\x{1f3}b")
1376
1a147d38 1377where the format expects to process a sequence of bytes (character with a
6903afa2 1378value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1379uses the character values modulus 256 instead, as if you had provided:
1380
1381 pack("u", "\x{f3}b")
1382
1383=item Character(s) in '%c' format wrapped in unpack
1384
1385(W unpack) You tried something like
1386
1387 unpack("s", "\x{1f3}b")
1388
1a147d38 1389where the format expects to process a sequence of bytes (character with a
6903afa2 1390value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1391uses the character values modulus 256 instead, as if you had provided:
1392
1393 unpack("s", "\x{f3}b")
1394
f866a7cd
FC
1395=item "\c%c" is more clearly written simply as "%s"
1396
1397(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1398non-printable characters. You used it for a printable one, which is better
1399written as simply itself, perhaps preceded by a backslash for non-word
1400characters.
1401
6651ba0b
FC
1402=item Cloning substitution context is unimplemented
1403
1404(F) Creating a new thread inside the C<s///> operator is not supported.
1405
abc7ecad
SP
1406=item closedir() attempted on invalid dirhandle %s
1407
1408(W io) The dirhandle you tried to close is either closed or not really
1409a dirhandle. Check your control flow.
1410
5a25739d
FC
1411=item close() on unopened filehandle %s
1412
1413(W unopened) You tried to close a filehandle that was never opened.
1414
541ed3a9
FC
1415=item Closure prototype called
1416
1417(F) If a closure has attributes, the subroutine passed to an attribute
1418handler is the prototype that is cloned when a new closure is created.
1419This subroutine cannot be called.
1420
49704364
LW
1421=item Code missing after '/'
1422
6903afa2
FC
1423(F) You had a (sub-)template that ends with a '/'. There must be
1424another template code following the slash. See L<perlfunc/pack>.
49704364 1425
5a25739d
FC
1426=item Code point 0x%X is not Unicode, may not be portable
1427
2d88a86a 1428(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1429of U+10FFFF.
1430
1431Perl allows strings to contain a superset of Unicode code points, up
1432to the limit of what is storable in an unsigned integer on your system,
1433but these may not be accepted by other languages/systems. At one time,
1434it was legal in some standards to have code points up to 0x7FFF_FFFF,
1435but not higher. Code points above 0xFFFF_FFFF require larger than a
143632 bit word.
0876b9a0 1437
6df41af2
GS
1438=item %s: Command not found
1439
a892b81a 1440(A) You've accidentally run your script through B<csh> or another shell
f738a371 1441instead of Perl. Check the #! line, or manually feed your script
a892b81a 1442into Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1443
1444 #!/usr/bin/perl -w
6df41af2 1445
7a2e2cd6
PP
1446=item Compilation failed in require
1447
1448(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1449Perl uses this generic message when none of the errors that it
1450encountered were severe enough to halt compilation immediately.
7a2e2cd6 1451
c3464db5
DD
1452=item Complex regular subexpression recursion limit (%d) exceeded
1453
be771a83
GS
1454(W regexp) The regular expression engine uses recursion in complex
1455situations where back-tracking is required. Recursion depth is limited
1456to 32766, or perhaps less in architectures where the stack cannot grow
1457arbitrarily. ("Simple" and "medium" situations are handled without
1458recursion and are not subject to a limit.) Try shortening the string
1459under examination; looping in Perl code (e.g. with C<while>) rather than
1460in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1461that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1462on I<Mastering Regular Expressions>.)
c3464db5 1463
69282e91 1464=item connect() on closed socket %s
a0d0e21e 1465
be771a83
GS
1466(W closed) You tried to do a connect on a closed socket. Did you forget
1467to check the return value of your socket() call? See
1468L<perlfunc/connect>.
a0d0e21e 1469
e21e7c6a
FC
1470=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1471
1472(F) The subroutine registered to handle constant overloading
1473(see L<overload>) or a custom charnames handler (see
1474L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1475
1476=item Constant(%s): $^H{%s} is not defined
1477
1478(F) The parser found inconsistencies while attempting to define an
1479overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1480L<overload> pragma?
e21e7c6a 1481
779c5bc9
GS
1482=item Constant is not %s reference
1483
1484(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1485is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1486The message indicates the type of reference that was expected. This
be771a83 1487usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1488See L<perlsub/"Constant Functions"> and L<constant>.
1489
4cee8e80
CS
1490=item Constant subroutine %s redefined
1491
aeb94125
FC
1492(W redefine)(S) You redefined a subroutine which had previously
1493been eligible for inlining. See L<perlsub/"Constant Functions">
1494for commentary and workarounds.
4cee8e80 1495
9607fc9c
PP
1496=item Constant subroutine %s undefined
1497
be771a83
GS
1498(W misc) You undefined a subroutine which had previously been eligible
1499for inlining. See L<perlsub/"Constant Functions"> for commentary and
1500workarounds.
9607fc9c 1501
5a25739d
FC
1502=item Constant(%s) unknown
1503
1504(F) The parser found inconsistencies either while attempting
1505to define an overloaded constant, or when trying to find the
1506character name specified in the C<\N{...}> escape. Perhaps you
1507forgot to load the corresponding L<overload> pragma?.
1508
e7ea3e70
IZ
1509=item Copy method did not return a reference
1510
6903afa2 1511(F) The method which overloads "=" is buggy. See
13a2d996 1512L<overload/Copy Constructor>.
e7ea3e70 1513
4aaa4757
FC
1514=item &CORE::%s cannot be called directly
1515
1516(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1517with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1518in this package cannot yet be called that way, but must be
1519called as barewords. Something like this will work:
1520
1521 BEGIN { *shove = \&CORE::push; }
1522 shove @array, 1,2,3; # pushes on to @array
1523
6798c92b
GS
1524=item CORE::%s is not a keyword
1525
1526(F) The CORE:: namespace is reserved for Perl keywords.
1527
675fa9ff
FC
1528=item Corrupted regexp opcode %d > %d
1529
1530(P) This is either an error in Perl, or, if you're using
1531one, your L<custom regular expression engine|perlreapi>. If not the
1532latter, report the problem through the L<perlbug> utility.
1533
a0d0e21e
LW
1534=item corrupted regexp pointers
1535
1536(P) The regular expression engine got confused by what the regular
1537expression compiler gave it.
1538
1539=item corrupted regexp program
1540
be771a83
GS
1541(P) The regular expression engine got passed a regexp program without a
1542valid magic number.
a0d0e21e 1543
de42a5a9 1544=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1545
1546(P) The malloc package that comes with Perl had an internal failure.
1547
49704364
LW
1548=item Count after length/code in unpack
1549
1550(F) You had an unpack template indicating a counted-length string, but
1551you have also specified an explicit size for the string. See
1552L<perlfunc/pack>.
1553
f2cccb4c
KW
1554=for comment
1555The following are used in lib/diagnostics.t for testing two =items that
1556share the same description. Changes here need to be propagated to there
1557
6651ba0b
FC
1558=item Deep recursion on anonymous subroutine
1559
a0d0e21e
LW
1560=item Deep recursion on subroutine "%s"
1561
be771a83
GS
1562(W recursion) This subroutine has called itself (directly or indirectly)
1563100 times more than it has returned. This probably indicates an
1564infinite recursion, unless you're writing strange benchmark programs, in
1565which case it indicates something else.
a0d0e21e 1566
aad1d01f
NC
1567This threshold can be changed from 100, by recompiling the F<perl> binary,
1568setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1569
f10b0346 1570=item defined(@array) is deprecated
69794302 1571
be771a83
GS
1572(D deprecated) defined() is not usually useful on arrays because it
1573checks for an undefined I<scalar> value. If you want to see if the
64977eb6 1574array is empty, just use C<if (@array) { # not empty }> for example.
69794302 1575
f10b0346 1576=item defined(%hash) is deprecated
69794302 1577
f0ec9725
KR
1578(D deprecated) C<defined()> is not usually right on hashes and has been
1579discouraged since 5.004.
1580
1581Although C<defined %hash> is false on a plain not-yet-used hash, it
1582becomes true in several non-obvious circumstances, including iterators,
1583weak references, stash names, even remaining true after C<undef %hash>.
1584These things make C<defined %hash> fairly useless in practice.
1585
1586If a check for non-empty is what you wanted then just put it in boolean
1587context (see L<perldata/Scalar values>):
16546e45
KR
1588
1589 if (%hash) {
1590 # not empty
1591 }
1592
f0ec9725
KR
1593If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1594variable exists then that's never really been reliable, and isn't
1595a good way to enquire about the features of a package, or whether
1596it's loaded, etc.
1597
69794302 1598
e0e4a6e3
FC
1599=item (?(DEFINE)....) does not allow branches in regex; marked by
1600S<<-- HERE> in m/%s/
bcb95744 1601
6903afa2 1602(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1603most likely cause of this error is that you left out a parenthesis inside
1604of the C<....> part.
1605
9e3ec65c 1606The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1607discovered.
1608
62658f4d
PM
1609=item %s defines neither package nor VERSION--version check failed
1610
1611(F) You said something like "use Module 42" but in the Module file
1612there are neither package declarations nor a C<$VERSION>.
1613
36447869
FC
1614=item delete argument is index/value array slice, use array slice
1615
1616(F) You used index/value array slice syntax (C<%array[...]>) as
1617the argument to C<delete>. You probably meant C<@array[...]> with
1618an @ symbol instead.
1619
1620=item delete argument is key/value hash slice, use hash slice
1621
1622(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1623C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1624
0ffcbc25
FC
1625=item delete argument is not a HASH or ARRAY element or slice
1626
4a0af295 1627(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1628such as:
1629
1630 $foo{$bar}
1631 $ref->{"susie"}[12]
1632
1633or a hash or array slice, such as:
1634
1635 @foo[$bar, $baz, $xyzzy]
1636 @{$ref->[12]}{"susie", "queue"}
1637
fc36a67e
PP
1638=item Delimiter for here document is too long
1639
be771a83
GS
1640(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1641long for Perl to handle. You have to be seriously twisted to write code
1642that triggers this error.
fc36a67e 1643
6d3b25aa
RGS
1644=item Deprecated use of my() in false conditional
1645
fa816bf3
FC
1646(D deprecated) You used a declaration similar to C<my $x if 0>. There
1647has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1648not to be cleared at scope exit when its declaration includes a false
6903afa2 1649conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1650static variable. Since we intend to fix this bug, we don't want people
6903afa2 1651relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1652declaring the variable in a separate block outside the function, eg
36fb85f3 1653
6d3b25aa
RGS
1654 sub f { my $x if 0; return $x++ }
1655
1656becomes
1657
1658 { my $x; sub f { return $x++ } }
1659
ea9d9ebc 1660Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1661lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1662
1663 sub f { state $x; return $x++ }
1664
500ab966
RGS
1665=item DESTROY created new reference to dead object '%s'
1666
1667(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1668just being DESTROYed. Perl is confused, and prefers to abort rather
1669than to create a dangling reference.
500ab966 1670
3cdd684c
TP
1671=item Did not produce a valid header
1672
1673See Server error.
1674
6df41af2
GS
1675=item %s did not return a true value
1676
1677(F) A required (or used) file must return a true value to indicate that
1678it compiled correctly and ran its initialization code correctly. It's
1679traditional to end such a file with a "1;", though any true value would
1680do. See L<perlfunc/require>.
1681
cc507455 1682=item (Did you mean &%s instead?)
4633a7c4 1683
413ff9f6
FC
1684(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1685some such.
4633a7c4 1686
cc507455 1687=item (Did you mean "local" instead of "our"?)
33633739 1688
be771a83
GS
1689(W misc) Remember that "our" does not localize the declared global
1690variable. You have declared it again in the same lexical scope, which
1691seems superfluous.
33633739 1692
cc507455 1693=item (Did you mean $ or @ instead of %?)
a0d0e21e 1694
be771a83
GS
1695(W) You probably said %hash{$key} when you meant $hash{$key} or
1696@hash{@keys}. On the other hand, maybe you just meant %hash and got
1697carried away.
748a9306 1698
7e1af8bc 1699=item Died
5f05dabc
PP
1700
1701(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1702you called it with no args and C<$@> was empty.
5f05dabc 1703
3cdd684c
TP
1704=item Document contains no data
1705
1706See Server error.
1707
62658f4d
PM
1708=item %s does not define %s::VERSION--version check failed
1709
1710(F) You said something like "use Module 42" but the Module did not
943fc58e 1711define a C<$VERSION>.
62658f4d 1712
49704364
LW
1713=item '/' does not take a repeat count
1714
1715(F) You cannot put a repeat count of any kind right after the '/' code.
1716See L<perlfunc/pack>.
1717
95cb0d72
FC
1718=item Don't know how to get file name
1719
1720(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1721somehow called on another platform. This should not happen.
1722
4021c788 1723=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1724
1725(P) The internal handling of magical variables has been cursed.
1726
1727=item do_study: out of memory
1728
1729(P) This should have been caught by safemalloc() instead.
1730
6df41af2
GS
1731=item (Do you need to predeclare %s?)
1732
56da5a46
RGS
1733(S syntax) This is an educated guess made in conjunction with the message
1734"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1735name is being referenced that hasn't been declared yet. This may be
1736because of ordering problems in your file, or because of a missing
be771a83
GS
1737"sub", "package", "require", or "use" statement. If you're referencing
1738something that isn't defined yet, you don't actually have to define the
1739subroutine or package before the current location. You can use an empty
1740"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1741
ac206dc8
RGS
1742=item dump() better written as CORE::dump()
1743
1744(W misc) You used the obsolescent C<dump()> built-in function, without fully
1745qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1746
84d78eb7
YO
1747=item dump is not supported
1748
1749(F) Your machine doesn't support dump/undump.
1750
a0d0e21e
LW
1751=item Duplicate free() ignored
1752
be771a83
GS
1753(S malloc) An internal routine called free() on something that had
1754already been freed.
a0d0e21e 1755
1109a392
MHM
1756=item Duplicate modifier '%c' after '%c' in %s
1757
35f0cd76
FC
1758(W unpack) You have applied the same modifier more than once after a
1759type in a pack template. See L<perlfunc/pack>.
1109a392 1760
0953b66b
FC
1761=item each on reference is experimental
1762
0773cb3e
FC
1763(S experimental::autoderef) C<each> with a scalar argument is experimental
1764and may change or be removed in a future Perl version. If you want to
1765take the risk of using this feature, simply disable this warning:
0953b66b 1766
d401967c 1767 no warnings "experimental::autoderef";
0953b66b 1768
4633a7c4
LW
1769=item elseif should be elsif
1770
fa816bf3
FC
1771(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1772it's ugly. Your code will be interpreted as an attempt to call a method
1773named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1774unlikely to be what you want.
1775
e0e4a6e3 1776=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1777
af6f566e 1778(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1779described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1780a regular expression without specifying the property name.
ab13f0c7 1781
85ab1d1d 1782=item entering effective %s failed
5ff3f7a4 1783
85ab1d1d 1784(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1785effective uids or gids failed.
1786
c038024b
RGS
1787=item %ENV is aliased to %s
1788
1789(F) You're running under taint mode, and the C<%ENV> variable has been
1790aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1791program's environment. This is potentially insecure.
c038024b 1792
748a9306
LW
1793=item Error converting file specification %s
1794
5f05dabc 1795(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1796specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1797single form when it must operate on them directly. Either you've passed
1798an invalid file specification to Perl, or you've found a case the
1799conversion routines don't handle. Drat.
748a9306 1800
ad19ef22 1801=item Eval-group in insecure regular expression
e4d48cc9 1802
be771a83
GS
1803(F) Perl detected tainted data when trying to compile a regular
1804expression that contains the C<(?{ ... })> zero-width assertion, which
1805is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1806
ad19ef22 1807=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1808
be771a83
GS
1809(F) Perl tried to compile a regular expression containing the
1810C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1811pattern contains interpolated values. Since that is a security risk,
1812it is not allowed. If you insist, you may still do this by using the
1813C<re 'eval'> pragma or by explicitly building the pattern from an
1814interpolated string at run time and using that in an eval(). See
1815L<perlre/(?{ code })>.
e4d48cc9 1816
ad19ef22 1817=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1818
be771a83
GS
1819(F) A regular expression contained the C<(?{ ... })> zero-width
1820assertion, but that construct is only allowed when the C<use re 'eval'>
1821pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1822
e0e4a6e3
FC
1823=item EVAL without pos change exceeded limit in regex; marked by
1824S<<-- HERE> in m/%s/
1a147d38
YO
1825
1826(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1827any text. Restructure the pattern so that text is consumed.
1a147d38 1828
9e3ec65c 1829The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1830discovered.
1831
fc36a67e
PP
1832=item Excessively long <> operator
1833
1834(F) The contents of a <> operator may not exceed the maximum size of a
1835Perl identifier. If you're just trying to glob a long list of
1836filenames, try using the glob() operator, or put the filenames into a
1837variable and glob that.
1838
ed9aa3b7
SG
1839=item exec? I'm not *that* kind of operating system
1840
af8bb25a 1841(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1842OS. See L<perlport>.
ed9aa3b7 1843
fe13d51d 1844=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1845
1846(F) The final summary message when a Perl compilation fails.
1847
0ffcbc25
FC
1848=item exists argument is not a HASH or ARRAY element or a subroutine
1849
4a0af295 1850(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1851subroutine with an ampersand, such as:
1852
1853 $foo{$bar}
1854 $ref->{"susie"}[12]
1855 &do_something
1856
1857=item exists argument is not a subroutine name
1858
ccfc2567
FC
1859(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1860and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1861
a0d0e21e
LW
1862=item Exiting eval via %s
1863
be771a83
GS
1864(W exiting) You are exiting an eval by unconventional means, such as a
1865goto, or a loop control statement.
e476b1b5
GS
1866
1867=item Exiting format via %s
1868
9a2ff54b 1869(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1870goto, or a loop control statement.
a0d0e21e 1871
0a753a76
PP
1872=item Exiting pseudo-block via %s
1873
be771a83
GS
1874(W exiting) You are exiting a rather special block construct (like a
1875sort block or subroutine) by unconventional means, such as a goto, or a
1876loop control statement. See L<perlfunc/sort>.
0a753a76 1877
a0d0e21e
LW
1878=item Exiting subroutine via %s
1879
be771a83
GS
1880(W exiting) You are exiting a subroutine by unconventional means, such
1881as a goto, or a loop control statement.
a0d0e21e
LW
1882
1883=item Exiting substitution via %s
1884
be771a83
GS
1885(W exiting) You are exiting a substitution by unconventional means, such
1886as a return, a goto, or a loop control statement.
a0d0e21e 1887
e0e4a6e3 1888=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1889
675fa9ff 1890(F) You wrote something like
c608e803
KW
1891
1892 (?13
1893
1894to denote a capturing group of the form
1895L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1896but omitted the C<")">.
1897
e0e4a6e3 1898=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1899
8b6fbf55
FC
1900(F) The C<(?[...])> extended character class regular expression construct
1901only allows character classes (including character class escapes like
1902C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1903containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1904This allows a regular expression containing just C<(?[...])> to be
1905interpolated. If you see this error message, then you probably
1906have some other C<(?...)> construct inside your character class. See
1907L<perlrecharclass/Extended Bracketed Character Classes>.
1908
30d9c59b
Z
1909=item Experimental subroutine signatures not enabled
1910
1911(F) To use subroutine signatures, you must first enable them:
1912
caa35032 1913 no warnings "experimental::signatures";
30d9c59b
Z
1914 use feature "signatures";
1915 sub foo ($left, $right) { ... }
1916
6da34ecb
FC
1917=item Experimental "%s" subs not enabled
1918
1919(F) To use lexical subs, you must first enable them:
1920
1921 no warnings 'experimental::lexical_subs';
1922 use feature 'lexical_subs';
1923 my sub foo { ... }
1924
7b8d334a
GS
1925=item Explicit blessing to '' (assuming package main)
1926
be771a83
GS
1927(W misc) You are blessing a reference to a zero length string. This has
1928the effect of blessing the reference into the package main. This is
1929usually not what you want. Consider providing a default target package,
1930e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1931
6df41af2
GS
1932=item %s: Expression syntax
1933
be771a83
GS
1934(A) You've accidentally run your script through B<csh> instead of Perl.
1935Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1936
1937=item %s failed--call queue aborted
1938
3c10abe3
AG
1939(F) An untrapped exception was raised while executing a UNITCHECK,
1940CHECK, INIT, or END subroutine. Processing of the remainder of the
1941queue of such routines has been prematurely ended.
6df41af2 1942
e0e4a6e3 1943=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1944
98d31c73 1945(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1946character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1947in your false range is interpreted as a literal "-". In a C<(?[...])>
1948construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1949the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1950the problem was discovered. See L<perlre>.
73b437c8 1951
1b1ee2ef 1952=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1953
be771a83
GS
1954(P) An error peculiar to VMS. Something untoward happened in a VMS
1955system service or RTL routine; Perl's exit status should provide more
1956details. The filename in "at %s" and the line number in "line %d" tell
1957you which section of the Perl source code is distressed.
a0d0e21e
LW
1958
1959=item fcntl is not implemented
1960
1961(F) Your machine apparently doesn't implement fcntl(). What is this, a
1962PDP-11 or something?
1963
22846ab4
AB
1964=item FETCHSIZE returned a negative value
1965
1966(F) A tied array claimed to have a negative number of elements, which
1967is not possible.
1968
f337b084
TH
1969=item Field too wide in 'u' format in pack
1970
d8b5cc61 1971(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1972which can't encode values above 63. So there is no point in asking for
1973a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1974C<u63> as the format.
f337b084 1975
af8c498a 1976=item Filehandle %s opened only for input
a0d0e21e 1977
6c8d78fb
HS
1978(W io) You tried to write on a read-only filehandle. If you intended
1979it to be a read-write filehandle, you needed to open it with "+<" or
1980"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1981write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1982
af8c498a 1983=item Filehandle %s opened only for output
a0d0e21e 1984
6c8d78fb
HS
1985(W io) You tried to read from a filehandle opened only for writing, If
1986you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1987with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1988read from the file, use "<". See L<perlfunc/open>. Another possibility
1989is that you attempted to open filedescriptor 0 (also known as STDIN) for
1990output (maybe you closed STDIN earlier?).
97828cef
RGS
1991
1992=item Filehandle %s reopened as %s only for input
1993
1994(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 1995as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
1996previously.
1997
1998=item Filehandle STDIN reopened as %s only for output
1999
2000(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2001as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2002
2003=item Final $ should be \$ or $name
2004
2005(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2006a literal dollar sign, or was meant to introduce a variable name that
2007happens to be missing. So you have to put either the backslash or the
2008name.
a0d0e21e 2009
56e90b21
GS
2010=item flock() on closed filehandle %s
2011
be771a83 2012(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2013some time before now. Check your control flow. flock() operates on
be771a83
GS
2014filehandles. Are you attempting to call flock() on a dirhandle by the
2015same name?
56e90b21 2016
6df41af2
GS
2017=item Format not terminated
2018
2019(F) A format must be terminated by a line with a solitary dot. Perl got
2020to the end of your file without finding such a line.
2021
a0d0e21e
LW
2022=item Format %s redefined
2023
e476b1b5 2024(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2025
2026 {
271595cc 2027 no warnings 'redefine';
a0d0e21e
LW
2028 eval "format NAME =...";
2029 }
2030
a0d0e21e
LW
2031=item Found = in conditional, should be ==
2032
e476b1b5 2033(W syntax) You said
a0d0e21e
LW
2034
2035 if ($foo = 123)
2036
2037when you meant
2038
2039 if ($foo == 123)
2040
2041(or something like that).
2042
6df41af2
GS
2043=item %s found where operator expected
2044
56da5a46
RGS
2045(S syntax) The Perl lexer knows whether to expect a term or an operator.
2046If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2047operator, it gives you this warning. Usually it indicates that an
2048operator or delimiter was omitted, such as a semicolon.
6df41af2 2049
a0d0e21e
LW
2050=item gdbm store returned %d, errno %d, key "%s"
2051
2052(S) A warning from the GDBM_File extension that a store failed.
2053
2054=item gethostent not implemented
2055
2056(F) Your C library apparently doesn't implement gethostent(), probably
2057because if it did, it'd feel morally obligated to return every hostname
2058on the Internet.
2059
69282e91 2060=item get%sname() on closed socket %s
a0d0e21e 2061
be771a83
GS
2062(W closed) You tried to get a socket or peer socket name on a closed
2063socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2064
748a9306
LW
2065=item getpwnam returned invalid UIC %#o for user "%s"
2066
2067(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2068C<getpwnam> operator returned an invalid UIC.
2069
6df41af2
GS
2070=item getsockopt() on closed socket %s
2071
be771a83
GS
2072(W closed) You tried to get a socket option on a closed socket. Did you
2073forget to check the return value of your socket() call? See
6df41af2
GS
2074L<perlfunc/getsockopt>.
2075
0f539b13
BF
2076=item given is experimental
2077
675fa9ff
FC
2078(S experimental::smartmatch) C<given> depends on smartmatch, which
2079is experimental, so its behavior may change or even be removed
2080in any future release of perl. See the explanation under
2081L<perlsyn/Experimental Details on given and when>.
0f539b13 2082
6df41af2
GS
2083=item Global symbol "%s" requires explicit package name
2084
a4edf47d 2085(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2086that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2087declared beforehand using "our", or explicitly qualified to say
2088which package the global variable is in (using "::").
6df41af2 2089
e476b1b5
GS
2090=item glob failed (%s)
2091
5ead438e 2092(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2093for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2094pattern that caused the external program to fail and exit with a
be771a83 2095nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2096resulted in a coredump, this may also mean that your csh (C shell)
2097is broken. If so, you should change all of the csh-related variables
2098in config.sh: If you have tcsh, make the variables refer to it as
2099if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2100all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2101think csh is missing. In either case, after editing config.sh, run
75b44862 2102C<./Configure -S> and rebuild Perl.
e476b1b5 2103
a0d0e21e
LW
2104=item Glob not terminated
2105
2106(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2107a term, so it's looking for the corresponding right angle bracket, and
2108not finding it. Chances are you left some needed parentheses out
2109earlier in the line, and you really meant a "less than".
a0d0e21e 2110
b35b96b6
JH
2111=item gmtime(%f) failed
2112
2113(W overflow) You called C<gmtime> with a number that it could not handle:
2114too large, too small, or NaN. The returned value is C<undef>.
2115
bcd05b94 2116=item gmtime(%f) too large
8b56d6ff 2117
e9200be3 2118(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2119it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2120date. This warning is also triggered with NaN (the special
fc003d4b
MS
2121not-a-number value).
2122
bcd05b94 2123=item gmtime(%f) too small
fc003d4b 2124
e9200be3 2125(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2126it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2127
6df41af2 2128=item Got an error from DosAllocMem
a0d0e21e 2129
6df41af2
GS
2130(P) An error peculiar to OS/2. Most probably you're using an obsolete
2131version of Perl, and this should not happen anyway.
a0d0e21e
LW
2132
2133=item goto must have label
2134
2135(F) Unlike with "next" or "last", you're not allowed to goto an
2136unspecified destination. See L<perlfunc/goto>.
2137
6651ba0b
FC
2138=item Goto undefined subroutine%s
2139
2140(F) You tried to call a subroutine with C<goto &sub> syntax, but
2141the indicated subroutine hasn't been defined, or if it was, it
2142has since been undefined.
2143
6fbc9859 2144=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2145S<<-- HERE> in m/%s/
1f4f6bf1
YO
2146
2147(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2148they must start with a non-digit word character. A common cause of
2149this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2150
5a25739d
FC
2151=item ()-group starts with a count
2152
2153(F) A ()-group started with a count. A count is supposed to follow
2154something: a template character or a ()-group. See L<perlfunc/pack>.
2155
fe13d51d 2156=item %s had compilation errors.
6df41af2
GS
2157
2158(F) The final summary message when a C<perl -c> fails.
2159
a0d0e21e
LW
2160=item Had to create %s unexpectedly
2161
be771a83
GS
2162(S internal) A routine asked for a symbol from a symbol table that ought
2163to have existed already, but for some reason it didn't, and had to be
2164created on an emergency basis to prevent a core dump.
a0d0e21e 2165
6df41af2
GS
2166=item %s has too many errors
2167
2168(F) The parser has given up trying to parse the program after 10 errors.
2169Further error messages would likely be uninformative.
2170
252aa082
JH
2171=item Hexadecimal number > 0xffffffff non-portable
2172
e476b1b5 2173(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2174(4294967295) and therefore non-portable between systems. See
2175L<perlport> for more on portability concerns.
252aa082 2176
8903cb82
PP
2177=item Identifier too long
2178
2179(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2180about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2181names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2182of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2183
e0e4a6e3
FC
2184=item Ignoring zero length \N{} in character class in regex; marked by
2185S<<-- HERE> in m/%s/
fc8cd66c 2186
b5e3739b
FC
2187(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2188zero-length sequence. When such an escape is used in a character class
2189its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2190been used, and the correct charname handler is in scope.
2191
6df41af2 2192=item Illegal binary digit %s
f675dbe5 2193
6df41af2 2194(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2195
6df41af2 2196=item Illegal binary digit %s ignored
a0d0e21e 2197
be771a83
GS
2198(W digit) You may have tried to use a digit other than 0 or 1 in a
2199binary number. Interpretation of the binary number stopped before the
2200offending digit.
a0d0e21e 2201
6597eb22
FC
2202=item Illegal character after '_' in prototype for %s : %s
2203
e4d150f1
FC
2204(W illegalproto) An illegal character was found in a prototype
2205declaration. The '_' in a prototype must be followed by a ';',
2206indicating the rest of the parameters are optional, or one of '@'
2207or '%', since those two will accept 0 or more final parameters.
6597eb22 2208
78d0fecf 2209=item Illegal character \%o (carriage return)
4fdae800 2210
d5898338 2211(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2212would any other whitespace, which means you should never see this error
2213when Perl was built using standard options. For some reason, your
2214version of Perl appears to have been built without this support. Talk
2215to your Perl administrator.
4fdae800 2216
d37a9538
ST
2217=item Illegal character in prototype for %s : %s
2218
197afce1 2219(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2220Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2221Perhaps you were trying to write a subroutine signature but didn't enable
2222that feature first (C<use feature 'signatures'>), so your signature was
2223instead interpreted as a bad prototype.
d37a9538 2224
904d85c5
RGS
2225=item Illegal declaration of anonymous subroutine
2226
2227(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2228you must always specify a block of code. See L<perlsub>.
904d85c5 2229
8e742a20
MHM
2230=item Illegal declaration of subroutine %s
2231
6903afa2 2232(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2233
a0d0e21e
LW
2234=item Illegal division by zero
2235
be771a83
GS
2236(F) You tried to divide a number by 0. Either something was wrong in
2237your logic, or you need to put a conditional in to guard against
2238meaningless input.
a0d0e21e 2239
6df41af2
GS
2240=item Illegal hexadecimal digit %s ignored
2241
be771a83
GS
2242(W digit) You may have tried to use a character other than 0 - 9 or
2243A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2244number stopped before the illegal character.
6df41af2 2245
a0d0e21e
LW
2246=item Illegal modulus zero
2247
be771a83
GS
2248(F) You tried to divide a number by 0 to get the remainder. Most
2249numbers don't take to this kindly.
a0d0e21e 2250
6df41af2 2251=item Illegal number of bits in vec
399388f4 2252
6df41af2
GS
2253(F) The number of bits in vec() (the third argument) must be a power of
2254two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2255
2256=item Illegal octal digit %s
a0d0e21e 2257
d1be9408 2258(F) You used an 8 or 9 in an octal number.
a0d0e21e 2259
399388f4 2260=item Illegal octal digit %s ignored
748a9306 2261
d1be9408 2262(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2263Interpretation of the octal number stopped before the 8 or 9.
748a9306 2264
e0e4a6e3 2265=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2266
675fa9ff 2267(F) You wrote something like
c608e803
KW
2268
2269 (?+foo)
2270
2271The C<"+"> is valid only when followed by digits, indicating a
2272capturing group. See
2273L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2274
375ed12a
JH
2275=item Illegal suidscript
2276
2277(F) The script run under suidperl was somehow illegal.
2278
fe13d51d 2279=item Illegal switch in PERL5OPT: -%c
6ff81951 2280
6df41af2 2281(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2282following switches: B<-[CDIMUdmtw]>.
6ff81951 2283
6df41af2 2284=item Ill-formed CRTL environ value "%s"
81e118e0 2285
75b44862 2286(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2287internal environ array, and encountered an element without the C<=>
2288delimiter used to separate keys from values. The element is ignored.
09bef843 2289
6df41af2 2290=item Ill-formed message in prime_env_iter: |%s|
54310121 2291
be771a83
GS
2292(W internal) A warning peculiar to VMS. Perl tried to read a logical
2293name or CLI symbol definition when preparing to iterate over %ENV, and
2294didn't see the expected delimiter between key and value, so the line was
2295ignored.
54310121 2296
6df41af2 2297=item (in cleanup) %s
9607fc9c 2298
be771a83
GS
2299(W misc) This prefix usually indicates that a DESTROY() method raised
2300the indicated exception. Since destructors are usually called by the
2301system at arbitrary points during execution, and often a vast number of
2302times, the warning is issued only once for any number of failures that
2303would otherwise result in the same message being repeated.
6df41af2 2304
be771a83
GS
2305Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2306also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2307
e0e4a6e3
FC
2308=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2309in m/%s/
0d0b4b3b 2310
675fa9ff 2311(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2312expression inside the construct was completely empty, or if there are
2313too many or few operands for the number of operators. Perl is not smart
2314enough to give you a more precise indication as to what is wrong.
2315
6fbc9859
MH
2316=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2317parent '%s'
2c7d6b9c
RGS
2318
2319(F) The method resolution order (MRO) of the given class is not
2320C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2321documentation in L<mro> for more information.
2322
979699d9
JH
2323=item In EBCDIC the v-string components cannot exceed 2147483647
2324
2325(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2326Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2327encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2328
6a2ed79a 2329=item Infinite recursion in regex
1a147d38
YO
2330
2331(F) You used a pattern that references itself without consuming any input
6903afa2 2332text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2333either consume text or fail.
2334
6dbe9451
NC
2335=item Initialization of state variables in list context currently forbidden
2336
6903afa2
FC
2337(F) Currently the implementation of "state" only permits the
2338initialization of scalar variables in scalar context. Re-write
2339C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2340context. Constructions such as C<state (@a) = foo()> will be
2341supported in a future perl release.
6dbe9451 2342
2186f873
FC
2343=item %%s[%s] in scalar context better written as $%s[%s]
2344
2345(W syntax) In scalar context, you've used an array index/value slice
2346(indicated by %) to select a single element of an array. Generally
2347it's better to ask for a scalar value (indicated by $). The difference
2348is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2349returns and when evaluating its argument, while C<%foo[&bar]> provides
2350a list context to its subscript, which can do weird things if you're
2351expecting only one subscript. When called in list context, it also
2352returns the index (what C<&bar> returns) in addition to the value.
2353
2354=item %%s{%s} in scalar context better written as $%s{%s}
2355
2356(W syntax) In scalar context, you've used a hash key/value slice
2357(indicated by %) to select a single element of a hash. Generally it's
2358better to ask for a scalar value (indicated by $). The difference
2359is that C<$foo{&bar}> always behaves like a scalar, both in the value
2360it returns and when evaluating its argument, while C<@foo{&bar}> and
2361provides a list context to its subscript, which can do weird things
2362if you're expecting only one subscript. When called in list context,
2363it also returns the key in addition to the value.
2364
a0d0e21e
LW
2365=item Insecure dependency in %s
2366
8b1a09fc 2367(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2368The tainting mechanism is turned on when you're running setuid or
2369setgid, or when you specify B<-T> to turn it on explicitly. The
2370tainting mechanism labels all data that's derived directly or indirectly
2371from the user, who is considered to be unworthy of your trust. If any
2372such data is used in a "dangerous" operation, you get this error. See
2373L<perlsec> for more information.
a0d0e21e
LW
2374
2375=item Insecure directory in %s
2376
be771a83
GS
2377(F) You can't use system(), exec(), or a piped open in a setuid or
2378setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2379the world. Also, the PATH must not contain any relative directory.
2380See L<perlsec>.
a0d0e21e 2381
62f468fc 2382=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2383
2384(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2385setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2386C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2387supplied (or potentially supplied) by the user. The script must set
2388the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2389
0e9be77f
DM
2390=item Insecure user-defined property %s
2391
2392(F) Perl detected tainted data when trying to compile a regular
2393expression that contains a call to a user-defined character property
2394function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2395See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2396
cd209d9d 2397=item In '(?...)', the '(' and '?' must be adjacent in regex;
e0e4a6e3 2398marked by S<<-- HERE> in m/%s/
675fa9ff 2399
cd209d9d 2400(F) The two-character sequence C<"(?"> in
675fa9ff
FC
2401this context in a regular expression pattern should be an
2402indivisible token, with nothing intervening between the C<"(">
cd209d9d 2403and the C<"?">, but you separated them.
675fa9ff 2404
b9ef414d
FC
2405=item Integer overflow in format string for %s
2406
2407(F) The indexes and widths specified in the format string of C<printf()>
2408or C<sprintf()> are too large. The numbers must not overflow the size of
2409integers for your architecture.
2410
a7ae9550
GS
2411=item Integer overflow in %s number
2412
35928bc5 2413(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2414either as a literal or as an argument to hex() or oct() is too big for
2415your architecture, and has been converted to a floating point number.
2416On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2417representable without overflow is 0xFFFFFFFF, 037777777777, or
24180b11111111111111111111111111111111 respectively. Note that Perl
2419transparently promotes all numbers to a floating point representation
2420internally--subject to loss of precision errors in subsequent
2421operations.
bbce6d69 2422
fc89ca81
FC
2423=item Integer overflow in srand
2424
2425(S overflow) The number you have passed to srand is too big to fit
2426in your architecture's integer representation. The number has been
2427replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2428architectures). This means you may be getting less randomness than
2429you expect, because different random seeds above the maximum will
2430return the same sequence of random numbers.
2431
46314c13
JP
2432=item Integer overflow in version
2433
18da5252
FC
2434=item Integer overflow in version %d
2435
784d71ed
FC
2436(W overflow) Some portion of a version initialization is too large for
2437the size of integers for your architecture. This is not a warning
f084e84f 2438because there is no rational reason for a version to try and use an
784d71ed
FC
2439element larger than typically 2**32. This is usually caused by trying
2440to use some odd mathematical operation as a version, like 100/9.
46314c13 2441
e0e4a6e3 2442=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2443
2444(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2445The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2446discovered.
2447
748a9306
LW
2448=item Internal inconsistency in tracking vforks
2449
be771a83
GS
2450(S) A warning peculiar to VMS. Perl keeps track of the number of times
2451you've called C<fork> and C<exec>, to determine whether the current call
2452to C<exec> should affect the current script or a subprocess (see
2453L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2454Perl is making a guess and treating this C<exec> as a request to
2455terminate the Perl script and execute the specified command.
748a9306 2456
870978ae
FC
2457=item internal %<num>p might conflict with future printf extensions
2458
2459(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2460formatting follows a slightly different set of rules when called from
2461C or XS code. Specifically, formats consisting of digits followed
2462by "p" (e.g., "%7p") are reserved for future use. If you see this
2463message, then an XS module tried to call that routine with one such
2464reserved format.
2465
e0e4a6e3 2466=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2467
fa816bf3 2468(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2469S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2470discovered.
a0d0e21e 2471
6df41af2
GS
2472=item %s (...) interpreted as function
2473
75b44862 2474(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2475followed by parentheses turns into a function, with all the list
64977eb6 2476operators arguments found inside the parentheses. See
13a2d996 2477L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2478
09bef843
SB
2479=item Invalid %s attribute: %s
2480
a4a4c9e2 2481(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2482by Perl or by a user-supplied handler. See L<attributes>.
2483
2484=item Invalid %s attributes: %s
2485
a4a4c9e2 2486(F) The indicated attributes for a subroutine or variable were not
be771a83 2487recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2488
e0e4a6e3
FC
2489=item Invalid character in charnames alias definition; marked by
2490S<<-- HERE> in '%s
225fb84f
KW
2491
2492(F) You tried to create a custom alias for a character name, with
2493the C<:alias> option to C<use charnames> and the specified character in
2494the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2495
c8028aa6
TC
2496=item Invalid \0 character in %s for %s: %s\0%s
2497
fa3234e3
FC
2498(W syscalls) Embedded \0 characters in pathnames or other system call
2499arguments produce a warning as of 5.20. The parts after the \0 were
2500formerly ignored by system calls.
c8028aa6 2501
e0e4a6e3 2502=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2503
2504(F) Only certain characters are valid for character names. The
2505indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2506
c635e13b
PP
2507=item Invalid conversion in %s: "%s"
2508
be771a83
GS
2509(W printf) Perl does not understand the given format conversion. See
2510L<perlfunc/sprintf>.
c635e13b 2511
e0e4a6e3
FC
2512=item Invalid escape in the specified encoding in regex; marked by
2513S<<-- HERE> in m/%s/
9e08bc66 2514
98d31c73 2515(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2516didn't correspond to a single character through the conversion
2517from the encoding specified by the encoding pragma.
98d31c73
FC
2518The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2519instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2520The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2521escape was discovered.
2522
8149aa9f
FC
2523=item Invalid hexadecimal number in \N{U+...}
2524
e0e4a6e3
FC
2525=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2526S<<-- HERE> in m/%s/
aec0ef10 2527
8149aa9f 2528(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2529number. Either it is empty, or you tried to use a character other than
25300 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2531
6651ba0b
FC
2532=item Invalid module name %s with -%c option: contains single ':'
2533
2534(F) The module argument to perl's B<-m> and B<-M> command-line options
2535cannot contain single colons in the module name, but only in the
2536arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2537B<-MFoo:Bar=baz> is not.
2538
2c7d6b9c
RGS
2539=item Invalid mro name: '%s'
2540
162a3e34
FC
2541(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2542where C<foo> is not a valid method resolution order (MRO). Currently,
2543the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2544a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2545
40e4140b
FC
2546=item Invalid negative number (%s) in chr
2547
2548(W utf8) You passed a negative number to C<chr>. Negative numbers are
2549not valid characters numbers, so it return the Unicode replacement
2550character (U+FFFD).
2551
6651ba0b
FC
2552=item invalid option -D%c, use -D'' to see choices
2553
8ff21bfe
FC
2554(S debugging) Perl was called with invalid debugger flags. Call perl
2555with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2556See also L<perlrun/-Dletters>.
6651ba0b 2557
e0e4a6e3 2558=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2559
2560(F) The range specified in a character class had a minimum character
7253e4e3
RK
2561greater than the maximum character. One possibility is that you forgot the
2562C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2563up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2564problem was discovered. See L<perlre>.
6df41af2 2565
d1573ac7 2566=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2567
2568(F) The range specified in the tr/// or y/// operator had a minimum
2569character greater than the maximum character. See L<perlop>.
2570
09bef843
SB
2571=item Invalid separator character %s in attribute list
2572
0120eecf 2573(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2574elements of an attribute list. If the previous attribute had a
2575parenthesised parameter list, perhaps that list was terminated too soon.
2576See L<attributes>.
09bef843 2577
b4581f09
JH
2578=item Invalid separator character %s in PerlIO layer specification %s
2579
2bfc5f71
FC
2580(W layer) When pushing layers onto the Perl I/O system, something other
2581than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2582If the previous attribute had a parenthesised parameter list, perhaps that
2583list was terminated too soon.
2584
2c86d456
DG
2585=item Invalid strict version format (%s)
2586
fa816bf3 2587(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2588A "strict" version number is a positive decimal number (integer or
2589decimal-fraction) without exponentiation or else a dotted-decimal
2590v-string with a leading 'v' character and at least three components.
a6485a24 2591The parenthesized text indicates which criteria were not met.
2c86d456
DG
2592See the L<version> module for more details on allowed version formats.
2593
49704364 2594=item Invalid type '%s' in %s
96e4d5b1 2595
49704364
LW
2596(F) The given character is not a valid pack or unpack type.
2597See L<perlfunc/pack>.
6728c851 2598
49704364 2599(W) The given character is not a valid pack or unpack type but used to be
75b44862 2600silently ignored.
96e4d5b1 2601
2c86d456
DG
2602=item Invalid version format (%s)
2603
fa816bf3 2604(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2605A "lax" version number is a positive decimal number (integer or
2606decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2607v-string. If the v-string has fewer than three components, it
2608must have a leading 'v' character. Otherwise, the leading 'v' is
2609optional. Both decimal and dotted-decimal versions may have a
2610trailing "alpha" component separated by an underscore character
2611after a fractional or dotted-decimal component. The parenthesized
2612text indicates which criteria were not met. See the L<version> module
2613for more details on allowed version formats.
46314c13 2614
798ae1b7
DG
2615=item Invalid version object
2616
fa816bf3
FC
2617(F) The internal structure of the version object was invalid.
2618Perhaps the internals were modified directly in some way or
2619an arbitrary reference was blessed into the "version" class.
798ae1b7 2620
cd209d9d 2621=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2622marked by S<<-- HERE> in m/%s/
675fa9ff 2623
cd209d9d 2624(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2625this context in a regular expression pattern should be an
2626indivisible token, with nothing intervening between the C<"(">
cd209d9d 2627and the C<"*">, but you separated them.
675fa9ff 2628
a0d0e21e
LW
2629=item ioctl is not implemented
2630
2631(F) Your machine apparently doesn't implement ioctl(), which is pretty
2632strange for a machine that supports C.
2633
c289d2f7
JH
2634=item ioctl() on unopened %s
2635
2636(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2637Check your control flow and number of arguments.
c289d2f7 2638
fe13d51d 2639=item IO layers (like '%s') unavailable
363c40c4
SB
2640
2641(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2642you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2643with 'useperlio'.
2644
80cbd5ad
JH
2645=item IO::Socket::atmark not implemented on this architecture
2646
2647(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2648neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2649
4f650b80 2650=item $* is no longer supported
b4581f09 2651
4f650b80 2652(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2653perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2654previous versions of perl the use of C<$*> enabled or disabled multi-line
2655matching within a string.
4fd19576
B
2656
2657Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2658modifiers. You can enable C</m> for a lexical scope (even a whole file)
2659with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2660then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2661
8ae1fe26
RGS
2662=item $# is no longer supported
2663
a58ac25e 2664(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2665perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2666should use the printf/sprintf functions instead.
8ae1fe26 2667
ccf3535a 2668=item '%s' is not a code reference
6ad11d81 2669
6903afa2
FC
2670(W overload) The second (fourth, sixth, ...) argument of
2671overload::constant needs to be a code reference. Either
2672an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2673
ccf3535a 2674=item '%s' is not an overloadable type
6ad11d81 2675
04a80ee0
RGS
2676(W overload) You tried to overload a constant type the overload package is
2677unaware of.
6ad11d81 2678
5a25739d
FC
2679=item -i used with no filenames on the command line, reading from STDIN
2680
2681(S inplace) The C<-i> option was passed on the command line, indicating
2682that the script is intended to edit files in place, but no files were
2683given. This is usually a mistake, since editing STDIN in place doesn't
2684make sense, and can be confusing because it can make perl look like
2685it is hanging when it is really just trying to read from STDIN. You
2686should either pass a filename to edit, or remove C<-i> from the command
2687line. See L<perlrun> for more details.
2688
aec0ef10 2689=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2690
2691(P) The regular expression parser is confused.
2692
0953b66b
FC
2693=item keys on reference is experimental
2694
0773cb3e
FC
2695(S experimental::autoderef) C<keys> with a scalar argument is experimental
2696and may change or be removed in a future Perl version. If you want to
2697take the risk of using this feature, simply disable this warning:
0953b66b 2698
d401967c 2699 no warnings "experimental::autoderef";
0953b66b 2700
a0d0e21e
LW
2701=item Label not found for "last %s"
2702
be771a83
GS
2703(F) You named a loop to break out of, but you're not currently in a loop
2704of that name, not even if you count where you were called from. See
2705L<perlfunc/last>.
a0d0e21e
LW
2706
2707=item Label not found for "next %s"
2708
2709(F) You named a loop to continue, 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
2713=item Label not found for "redo %s"
2714
2715(F) You named a loop to restart, but you're not currently in a loop of
2716that name, not even if you count where you were called from. See
2717L<perlfunc/last>.
2718
85ab1d1d 2719=item leaving effective %s failed
5ff3f7a4 2720
85ab1d1d 2721(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2722effective uids or gids failed.
2723
49704364
LW
2724=item length/code after end of string in unpack
2725
d7f8936a 2726(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2727length/code combination tried to obtain more data. This results in
2728an undefined value for the length. See L<perlfunc/pack>.
49704364 2729
25e26107 2730=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2731
0d46a4e7
FC
2732(W syntax) You used length() on either an array or a hash when you
2733probably wanted a count of the items.
e508c8a4
MH
2734
2735Array size can be obtained by doing:
2736
2737 scalar(@array);
2738
2739The number of items in a hash can be obtained by doing:
2740
2741 scalar(keys %hash);
2742
f0e67a1d
Z
2743=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2744
d4fe7078
RS
2745(F) An extension is attempting to insert text into the current parse
2746(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2747couldn't be part of the current input. This is an inherent pitfall
2748of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2749it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2750
2751=item Lexing code internal error (%s)
2752
2753(F) Lexing code supplied by an extension violated the lexer's API in a
2754detectable way.
2755
69282e91 2756=item listen() on closed socket %s
a0d0e21e 2757
be771a83
GS
2758(W closed) You tried to do a listen on a closed socket. Did you forget
2759to check the return value of your socket() call? See
2760L<perlfunc/listen>.
a0d0e21e 2761
6651ba0b
FC
2762=item List form of piped open not implemented
2763
2764(F) On some platforms, notably Windows, the three-or-more-arguments
2765form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2766Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2767
b35b96b6
JH
2768=item localtime(%f) failed
2769
2770(W overflow) You called C<localtime> with a number that it could not handle:
2771too large, too small, or NaN. The returned value is C<undef>.
2772
bcd05b94 2773=item localtime(%f) too large
8b56d6ff 2774
e9200be3 2775(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2776than it can reliably handle and C<localtime> probably returned the
6903afa2 2777wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2778not-a-number value).
2779
bcd05b94 2780=item localtime(%f) too small
fc003d4b 2781
e9200be3 2782(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2783than it can reliably handle and C<localtime> probably returned the
e7a1a147 2784wrong date.
8b56d6ff 2785
58e23c8d 2786=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2787
2788(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2789handle. This restriction may be eased in a future release.
2e50fd82 2790
b88df990
NC
2791=item Lost precision when %s %f by 1
2792
e63e8a91
FC
2793(W imprecision) The value you attempted to increment or decrement by one
2794is too large for the underlying floating point representation to store
2795accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2796warning because it has already switched from integers to floating point
2797when values are too large for integers, and now even floating point is
2798insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2799
93fad930 2800=item lstat() on filehandle%s
2f7da168
RK
2801
2802(W io) You tried to do an lstat on a filehandle. What did you mean
2803by that? lstat() makes sense only on filenames. (Perl did a fstat()
2804instead on the filehandle.)
2805
345d70e3 2806=item lvalue attribute %s already-defined subroutine
bb3abb05 2807
345d70e3
FC
2808(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2809attribute on or off on a Perl subroutine that is already defined
2810does not always work properly. It may or may not do what you
2811want, depending on what code is inside the subroutine, with exact
2812details subject to change between Perl versions. Only do this
2813if you really know what you are doing.
bb3abb05 2814
885ef6f5
GG
2815=item lvalue attribute ignored after the subroutine has been defined
2816
345d70e3
FC
2817(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2818subroutine an lvalue subroutine after it has been defined is
2819not permitted. To make the subroutine an lvalue subroutine,
2820add the lvalue attribute to the definition, or put the C<sub
2821foo :lvalue;> declaration before the definition.
2822
2823See also L<attributes.pm|attributes>.
885ef6f5 2824
6f1b3ab0
FC
2825=item Magical list constants are not supported
2826
2827(F) You assigned a magical array to a stash element, and then tried
2828to use the subroutine from the same slot. You are asking Perl to do
2829something it cannot do, details subject to change between Perl versions.
2830
2db62bbc 2831=item Malformed integer in [] in pack
49704364 2832
2db62bbc 2833(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2834are permitted. See L<perlfunc/pack>.
2835
2836=item Malformed integer in [] in unpack
2837
2db62bbc 2838(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2839are permitted. See L<perlfunc/pack>.
2840
6df41af2
GS
2841=item Malformed PERLLIB_PREFIX
2842
2843(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2844
2845 prefix1;prefix2
2846
2847or
6df41af2
GS
2848 prefix1 prefix2
2849
be771a83
GS
2850with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2851a builtin library search path, prefix2 is substituted. The error may
2852appear if components are not found, or are too long. See
fecfaeb8 2853"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2854
2f758a16
ST
2855=item Malformed prototype for %s: %s
2856
d37a9538
ST
2857(F) You tried to use a function with a malformed prototype. The
2858syntax of function prototypes is given a brief compile-time check for
2859obvious errors like invalid characters. A more rigorous check is run
2860when the function is called.
30d9c59b
Z
2861Perhaps the function's author was trying to write a subroutine signature
2862but didn't enable that feature first (C<use feature 'signatures'>),
2863so the signature was instead interpreted as a bad prototype.
2f758a16 2864
ba210ebe
JH
2865=item Malformed UTF-8 character (%s)
2866
4d6f11e5 2867(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2868encoding rules, even though it had the UTF8 flag on.
ba210ebe 2869
2575c402
JW
2870One possible cause is that you set the UTF8 flag yourself for data that
2871you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28728-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2873
2874If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2875sequences are handled gracefully, but if you use C<:utf8>, the flag is
2876set without validating the data, possibly resulting in this error
2877message.
2878
2879See also L<Encode/"Handling Malformed Data">.
901b21bf 2880
107160e2
KW
2881=item Malformed UTF-8 character immediately after '%s'
2882
2883(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2884encoding rules. The message prints out the properly encoded characters
2885just before the first bad one. If C<utf8> warnings are enabled, a
2886warning is generated that gives more details about the type of
2887malformation.
2888
bde9e88d 2889=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2890
2891(F) The charnames handler returned malformed UTF-8.
2892
4a5d3a93
FC
2893=item Malformed UTF-8 string in '%c' format in unpack
2894
2895(F) You tried to unpack something that didn't comply with UTF-8 encoding
2896rules and perl was unable to guess how to make more progress.
2897
f337b084
TH
2898=item Malformed UTF-8 string in pack
2899
2900(F) You tried to pack something that didn't comply with UTF-8 encoding
2901rules and perl was unable to guess how to make more progress.
2902
2903=item Malformed UTF-8 string in unpack
2904
2905(F) You tried to unpack something that didn't comply with UTF-8 encoding
2906rules and perl was unable to guess how to make more progress.
2907
4a5d3a93 2908=item Malformed UTF-16 surrogate
f337b084 2909
4a5d3a93
FC
2910(F) Perl thought it was reading UTF-16 encoded character data but while
2911doing it Perl met a malformed Unicode surrogate.
2912
30d9c59b
Z
2913=item Mandatory parameter follows optional parameter
2914
2915(F) In a subroutine signature, you wrote something like "$a = undef,
2916$b", making an earlier parameter optional and a later one mandatory.
2917Parameters are filled from left to right, so it's impossible for the
2918caller to omit an earlier one and pass a later one. If you want to act
2919as if the parameters are filled from right to left, declare the rightmost
2920optional and then shuffle the parameters around in the subroutine's body.
2921
2d88a86a
KW
2922=item Matched non-Unicode code point 0x%X against Unicode property; may
2923not be portable
2924
2925(S non_unicode) Perl allows strings to contain a superset of
2926Unicode code points; each code point may be as large as what is storable
2927in an unsigned integer on your system, but these may not be accepted by
2928other languages/systems. This message occurs when you matched a string
2929containing such a code point against a regular expression pattern, and
2930the code point was matched against a Unicode property, C<\p{...}> or
2931C<\P{...}>. Unicode properties are only defined on Unicode code points,
2932so the result of this match is undefined by Unicode, but Perl (starting
2933in v5.20) treats non-Unicode code points as if they were typical
2934unassigned Unicode ones, and matched this one accordingly. Whether a
2935given property matches these code points or not is specified in
2936L<perluniprops/Properties accessible through \p{} and \P{}>.
2937
2938This message is suppressed (unless it has been made fatal) if it is
2939immaterial to the results of the match if the code point is Unicode or
2940not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2941the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2942Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2943every code point except these 22.)
2944
2945Getting this message indicates that the outcome of the match arguably
2946should have been the opposite of what actually happened. If you think
2947that is the case, you may wish to make the C<non_unicode> warnings
2948category fatal; if you agree with Perl's decision, you may wish to turn
2949off this category.
2950
2951See L<perlunicode/Beyond Unicode code points> for more information.
2952
e0e4a6e3
FC
2953=item %s matches null string many times in regex; marked by S<<-- HERE> in
2954m/%s/
4a5d3a93
FC
2955
2956(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2957regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2958shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2959See L<perlre>.
f337b084 2960
de42a5a9 2961=item Maximal count of pending signals (%u) exceeded
2563cec5 2962
6903afa2 2963(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2964usually indicates that your operating system tried to deliver signals
2965too fast (with a very high priority), starving the perl process from
2966resources it would need to reach a point where it can process signals
6903afa2 2967safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2968
25f58aea
PN
2969=item "%s" may clash with future reserved word
2970
2971(W) This warning may be due to running a perl5 script through a perl4
2972interpreter, especially if the word that is being warned about is
2973"use" or "my".
2974
0d2487cd 2975=item '%' may not be used in pack
6df41af2
GS
2976
2977(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2978checksumming process loses information, and you can't go the other way.
2979See L<perlfunc/unpack>.
6df41af2 2980
a0d0e21e
LW
2981=item Method for operation %s not found in package %s during blessing
2982
2983(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2984doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2985
3cdd684c
TP
2986=item Method %s not permitted
2987
2988See Server error.
2989
a0d0e21e
LW
2990=item Might be a runaway multi-line %s string starting on line %d
2991
2992(S) An advisory indicating that the previous error may have been caused
2993by a missing delimiter on a string or pattern, because it eventually
2994ended earlier on the current line.
2995
2996=item Misplaced _ in number
2997
d4ced10d
JH
2998(W syntax) An underscore (underbar) in a numeric constant did not
2999separate two digits.
a0d0e21e 3000
7baa4690
HS
3001=item Missing argument in %s
3002
3003(W uninitialized) A printf-type format required more arguments than were
3004supplied.
3005
9e81e6a1
RGS
3006=item Missing argument to -%c
3007
3008(F) The argument to the indicated command line switch must follow
3009immediately after the switch, without intervening spaces.
3010
ff3f963a 3011=item Missing braces on \N{}
423cee85 3012
e0e4a6e3 3013=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3014
4a2d328f 3015(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3016double-quotish context. This can also happen when there is a space
3017(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3018This modifier does not change the requirement that the brace immediately
3019follow the C<\N>.
423cee85 3020
f0a2b745
KW
3021=item Missing braces on \o{}
3022
3023(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3024
a0d0e21e
LW
3025=item Missing comma after first argument to %s function
3026
3027(F) While certain functions allow you to specify a filehandle or an
3028"indirect object" before the argument list, this ain't one of them.
3029
06eaf0bc
GS
3030=item Missing command in piped open
3031
be771a83
GS
3032(W pipe) You used the C<open(FH, "| command")> or
3033C<open(FH, "command |")> construction, but the command was missing or
3034blank.
06eaf0bc 3035
961ce445
RGS
3036=item Missing control char name in \c
3037
3038(F) A double-quoted string ended with "\c", without the required control
3039character name.
3040
591f5ca2
FC
3041=item Missing ']' in prototype for %s : %s
3042
bfe11873 3043(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3044
8767b1ab 3045=item Missing name in "%s sub"
6df41af2 3046
87444db5 3047(F) The syntax for lexically scoped subroutines requires that
be771a83 3048they have a name with which they can be found.
6df41af2
GS
3049
3050=item Missing $ on loop variable
3051
be771a83
GS
3052(F) Apparently you've been programming in B<csh> too much. Variables
3053are always mentioned with the $ in Perl, unlike in the shells, where it
3054can vary from one line to the next.
6df41af2 3055
cc507455 3056=item (Missing operator before %s?)
748a9306 3057
56da5a46
RGS
3058(S syntax) This is an educated guess made in conjunction with the message
3059"%s found where operator expected". Often the missing operator is a comma.
748a9306 3060
e0e4a6e3 3061=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3062
ff3f963a
KW
3063(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3064
4a68bf9d 3065=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3066
d32207c9
FC
3067(F) C<\N> has two meanings.
3068
3069The traditional one has it followed by a name enclosed in braces,
3070meaning the character (or sequence of characters) given by that
fa816bf3 3071name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3072double-quoted strings and regular expression patterns. In patterns,
3073it doesn't have the meaning an unescaped C<*> does.
3074
3075Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3076in patterns, namely to match a non-newline character. (This is short
3077for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3078
3079This can lead to some ambiguities. When C<\N> is not followed immediately
3080by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3081form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3082means to match the given quantity of non-newlines (in these examples,
30833; and 5 or more, respectively). In all other case, where there is a
3084C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3085
3086However, if there is no matching C<}>, Perl doesn't know if it was
3087mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3088If you meant the former, add the right brace; if you meant the latter,
3089escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3090
d98d5fff 3091=item Missing right curly or square bracket
a0d0e21e 3092
be771a83
GS
3093(F) The lexer counted more opening curly or square brackets than closing
3094ones. As a general rule, you'll find it's missing near the place you
3095were last editing.
a0d0e21e 3096
6df41af2
GS
3097=item (Missing semicolon on previous line?)
3098
56da5a46
RGS
3099(S syntax) This is an educated guess made in conjunction with the message
3100"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3101the previous line just because you saw this message.
3102
a0d0e21e
LW
3103=item Modification of a read-only value attempted
3104
3105(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3106constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3107catches that. But an easy way to do the same thing is:
3108
3109 sub mod { $_[0] = 1 }
3110 mod(2);
3111
3112Another way is to assign to a substr() that's off the end of the string.
3113
c5674021
PDF
3114Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3115is aliased to a constant in the look I<LIST>:
3116
b7e4ecc1
FC
3117 $x = 1;
3118 foreach my $n ($x, 2) {
3119 $n *= 2; # modifies the $x, but fails on attempt to
3120 } # modify the 2
c5674021 3121
7a4340ed 3122=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3123
3124(F) You tried to make an array value spring into existence, and the
3125subscript was probably negative, even counting from end of the array
3126backwards.
3127
7a4340ed 3128=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3129
be771a83
GS
3130(P) You tried to make a hash value spring into existence, and it
3131couldn't be created for some peculiar reason.
a0d0e21e
LW
3132
3133=item Module name must be constant
3134
3135(F) Only a bare module name is allowed as the first argument to a "use".
3136
be98fb35 3137=item Module name required with -%c option
6df41af2 3138
be98fb35
GS
3139(F) The C<-M> or C<-m> options say that Perl should load some module, but
3140you omitted the name of the module. Consult L<perlrun> for full details
3141about C<-M> and C<-m>.
6df41af2 3142
fe13d51d 3143=item More than one argument to '%s' open
ed9aa3b7 3144
6903afa2 3145(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3146can happen if you are trying to open a pipe to a command that takes a
3147list of arguments, but have forgotten to specify a piped open mode.
3148See L<perlfunc/open> for details.
3149
85396b18
FC
3150=item mprotect for COW string %p %u failed with %d
3151
3152(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3153L<perlguts/"Copy on Write">), but a shared string buffer
3154could not be made read-only.
3155
92951bce
FC
3156=item mprotect for %p %u failed with %d
3157
85396b18
FC
3158(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3159but an op tree could not be made read-only.
3160
3161=item mprotect RW for COW string %p %u failed with %d
3162
3163(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3164L<perlguts/"Copy on Write">), but a read-only shared string
3165buffer could not be made mutable.
3166
92951bce
FC
3167=item mprotect RW for %p %u failed with %d
3168
3169(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3170L<perlhacktips>), but a read-only op tree could not be made
3171mutable before freeing the ops.
92951bce 3172
a0d0e21e
LW
3173=item msg%s not implemented
3174
3175(F) You don't have System V message IPC on your system.
3176
3177=item Multidimensional syntax %s not supported
3178
75b44862
GS
3179(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3180They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3181
49704364 3182=item '/' must follow a numeric type in unpack
6df41af2 3183
49704364
LW
3184(F) You had an unpack template that contained a '/', but this did not
3185follow some unpack specification producing a numeric value.
3186See L<perlfunc/pack>.
6df41af2
GS
3187
3188=item "my sub" not yet implemented
3189
be771a83
GS
3190(F) Lexically scoped subroutines are not yet implemented. Don't try
3191that yet.
6df41af2 3192
5a25739d
FC
3193=item "my %s" used in sort comparison
3194
3195(W syntax) The package variables $a and $b are used for sort comparisons.
3196You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3197sort comparison block, and the variable had earlier been declared as a
3198lexical variable. Either qualify the sort variable with the package
3199name, or rename the lexical variable.
3200
fd1b7234 3201=item "my" variable %s can't be in a package
6df41af2 3202
be771a83
GS
3203(F) Lexically scoped variables aren't in a package, so it doesn't make
3204sense to try to declare one with a package qualifier on the front. Use
3205local() if you want to localize a package variable.
09bef843 3206
8149aa9f
FC
3207=item Name "%s::%s" used only once: possible typo
3208
c59aba6c
FC
3209(W once) Typographical errors often show up as unique variable
3210names. If you had a good reason for having a unique name, then
3211just mention it again somehow to suppress the message. The C<our>
08a33b6b 3212declaration is also provided for this purpose.
c59aba6c 3213
08a33b6b
AP
3214NOTE: This warning detects package symbols that have been used only
3215once. This means lexical variables will never trigger this warning.
3216It also means that all of the package variables $c, @c, %c, as well
3217as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3218format) are considered the same; if a program uses $c only once
3219but also uses any of the others it will not trigger this warning.
3220Symbols beginning with an underscore and symbols using special
3221identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3222
e0e4a6e3 3223=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3224
3225(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3226exactly 3 digits long. This helps catch some ambiguities. If your
3227constant is too short, add leading zeros, like
3228
3229 (?[ [ \078 ] ]) # Syntax error!
3230 (?[ [ \0078 ] ]) # Works
3231 (?[ [ \007 8 ] ]) # Clearer
3232
3233The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3234need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3235two separate things, you need to separate them:
0d0b4b3b
KW
3236
3237 (?[ [ \7776 ] ]) # Syntax error!
3238 (?[ [ \o{7776} ] ]) # One meaning
3239 (?[ [ \777 6 ] ]) # Another meaning
3240 (?[ [ \777 \006 ] ]) # Still another
3241
49704364
LW
3242=item Negative '/' count in unpack
3243
3244(F) The length count obtained from a length/code unpack operation was
3245negative. See L<perlfunc/pack>.
3246
a0d0e21e
LW
3247=item Negative length
3248
be771a83
GS
3249(F) You tried to do a read/write/send/recv operation with a buffer
3250length that is less than 0. This is difficult to imagine.
a0d0e21e 3251
ed9aa3b7
SG
3252=item Negative offset to vec in lvalue context
3253
3254(F) When C<vec> is called in an lvalue context, the second argument must be
3255greater than or equal to zero.
3256
e0e4a6e3 3257=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3258
6903afa2 3259(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3260So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3261whereabouts in the regular expression the problem was discovered.
a0d0e21e 3262
7253e4e3 3263Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3264C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3265
6df41af2 3266=item %s never introduced
a0d0e21e 3267
be771a83
GS
3268(S internal) The symbol in question was declared but somehow went out of
3269scope before it could possibly have been used.
a0d0e21e 3270
2c7d6b9c
RGS
3271=item next::method/next::can/maybe::next::method cannot find enclosing method
3272
3273(F) C<next::method> needs to be called within the context of a
3274real method in a real package, and it could not find such a context.
3275See L<mro>.
3276
5a25739d 3277=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3278marked by S<<-- HERE> in m/%s/
5a25739d 3279
32a77fbe
FC
3280(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3281bracketed character class, for the same reason that C<.> in a character
3282class loses its specialness: it matches almost everything, which is
3283probably not what you want.
5a25739d 3284
0b4ce96d 3285=item \N{} in character class restricted to one character in regex; marked
e0e4a6e3 3286by S<<-- HERE> in m/%s/
0b4ce96d
FC
3287
3288(F) Named Unicode character escapes C<(\N{...})> may return a
3289multi-character sequence. Such an escape may not be used in
3290a character class, because character classes always match one
3291character of input. Check that the correct escape has been used,
e0e4a6e3 3292and the correct charname handler is in scope. The S<<-- HERE> shows
0b4ce96d
FC
3293whereabouts in the regular expression the problem was discovered.
3294
e0e4a6e3
FC
3295=item \N{NAME} must be resolved by the lexer in regex; marked by
3296S<<-- HERE> in m/%s/
5a25739d
FC
3297
3298