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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
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189=item Argument "%s" treated as 0 in increment (++)
190
191(W numeric) The indicated string was fed as an argument to the C<++>
192operator which expects either a number or a string matching
193C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
194Auto-decrement> for details.
195
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196=item Array @%s missing the @ in argument %d of %s()
197
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198(D deprecated) Really old Perl let you omit the @ on array names in some
199spots. This is now heavily deprecated.
a0d0e21e 200
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201=item A sequence of multiple spaces in a charnames alias definition is deprecated
202
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203(D deprecated) You defined a character name which had multiple space
204characters in a row. Change them to single spaces. Usually these
205names are defined in the C<:alias> import argument to C<use charnames>, but
206they could be defined by a translator installed into C<$^H{charnames}>.
207See L<charnames/CUSTOM ALIASES>.
bd299e29 208
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209=item assertion botched: %s
210
21b5e840 211(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 212
0eacef8e 213=item Assertion %s failed: file "%s", line %d
a0d0e21e 214
21b5e840 215(X) A general assertion failed. The file in question must be examined.
a0d0e21e 216
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217=item Assigning non-zero to $[ is no longer possible
218
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219(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
220the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 221
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222=item Assignment to both a list and a scalar
223
224(F) If you assign to a conditional operator, the 2nd and 3rd arguments
225must either both be scalars or both be lists. Otherwise Perl won't
226know which context to supply to the right side.
227
2393f1b9 228=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 229
49293501 230(F) The failing code has attempted to get or set a key which is not in
2393f1b9 231the current set of allowed keys of a restricted hash.
49293501 232
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233=item Attempt to bless into a freed package
234
235(F) You wrote C<bless $foo> with one argument after somehow causing
236the current package to be freed. Perl cannot figure out what to
237do, so it throws up in hands in despair.
238
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239=item Attempt to bless into a reference
240
241(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 242the name of the package to bless the resulting object into. You've
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243supplied instead a reference to something: perhaps you wrote
244
245 bless $self, $proto;
246
247when you intended
248
249 bless $self, ref($proto) || $proto;
250
251If you actually want to bless into the stringified version
252of the reference supplied, you need to stringify it yourself, for
253example by:
254
255 bless $self, "$proto";
256
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257=item Attempt to clear deleted array
258
259(S debugging) An array was assigned to when it was being freed.
260Freed values are not supposed to be visible to Perl code. This
261can also happen if XS code calls C<av_clear> from a custom magic
262callback on the array.
263
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264=item Attempt to delete disallowed key '%s' from a restricted hash
265
266(F) The failing code attempted to delete from a restricted hash a key
267which is not in its key set.
268
269=item Attempt to delete readonly key '%s' from a restricted hash
270
271(F) The failing code attempted to delete a key whose value has been
272declared readonly from a restricted hash.
273
de42a5a9 274=item Attempt to free non-arena SV: 0x%x
a0d0e21e 275
f84fe999 276(S internal) All SV objects are supposed to be allocated from arenas
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277that will be garbage collected on exit. An SV was discovered to be
278outside any of those arenas.
a0d0e21e 279
12578ffb 280=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 281
f84fe999 282(S internal) Perl maintains a reference-counted internal table of
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283strings to optimize the storage and access of hash keys and other
284strings. This indicates someone tried to decrement the reference count
285of a string that can no longer be found in the table.
bbce6d69 286
7d5b40b4 287=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 288
f84fe999 289(S debugging) Mortalized values are supposed to be freed by the
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290free_tmps() routine. This indicates that something else is freeing the
291SV before the free_tmps() routine gets a chance, which means that the
292free_tmps() routine will be freeing an unreferenced scalar when it does
293try to free it.
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294
295=item Attempt to free unreferenced glob pointers
296
f84fe999 297(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 298
7d5b40b4 299=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 300
8f7e4d2c 301(S internal) Perl went to decrement the reference count of a scalar to
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302see if it would go to 0, and discovered that it had already gone to 0
303earlier, and should have been freed, and in fact, probably was freed.
304This could indicate that SvREFCNT_dec() was called too many times, or
305that SvREFCNT_inc() was called too few times, or that the SV was
306mortalized when it shouldn't have been, or that memory has been
307corrupted.
a0d0e21e 308
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309=item Attempt to pack pointer to temporary value
310
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311(W pack) You tried to pass a temporary value (like the result of a
312function, or a computed expression) to the "p" pack() template. This
313means the result contains a pointer to a location that could become
314invalid anytime, even before the end of the current statement. Use
315literals or global values as arguments to the "p" pack() template to
316avoid this warning.
84902520 317
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318=item Attempt to reload %s aborted.
319
320(F) You tried to load a file with C<use> or C<require> that failed to
321compile once already. Perl will not try to compile this file again
322unless you delete its entry from %INC. See L<perlfunc/require> and
323L<perlvar/%INC>.
324
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325=item Attempt to set length of freed array
326
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327(W misc) You tried to set the length of an array which has
328been freed. You can do this by storing a reference to the
329scalar representing the last index of an array and later
330assigning through that reference. For example
1b20cd17
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331
332 $r = do {my @a; \$#a};
333 $$r = 503
334
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335=item Attempt to use reference as lvalue in substr
336
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337(W substr) You supplied a reference as the first argument to substr()
338used as an lvalue, which is pretty strange. Perhaps you forgot to
339dereference it first. See L<perlfunc/substr>.
b7a902f4 340
c32124fe
NC
341=item Attribute "locked" is deprecated
342
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343(D deprecated) You have used the attributes pragma to modify the
344"locked" attribute on a code reference. The :locked attribute is
345obsolete, has had no effect since 5005 threads were removed, and
346will be removed in a future release of Perl 5.
c32124fe 347
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348=item Attribute prototype(%s) discards earlier prototype attribute in same sub
349
350(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
351example. Since each sub can only have one prototype, the earlier
352declaration(s) are discarded while the last one is applied.
353
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354=item Attribute "unique" is deprecated
355
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356(D deprecated) You have used the attributes pragma to modify
357the "unique" attribute on an array, hash or scalar reference.
358The :unique attribute has had no effect since Perl 5.8.8, and
359will be removed in a future release of Perl 5.
f1a3ce43 360
ccce04a4
FC
361=item av_reify called on tied array
362
363(S debugging) This indicates that something went wrong and Perl got I<very>
364confused about C<@_> or C<@DB::args> being tied.
365
de42a5a9 366=item Bad arg length for %s, is %u, should be %d
a0d0e21e 367
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368(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
369or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 370S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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371S<sizeof(struct shmid_ds *)>.
372
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373=item Bad evalled substitution pattern
374
496a33f5 375(F) You've used the C</e> switch to evaluate the replacement for a
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376substitution, but perl found a syntax error in the code to evaluate,
377most likely an unexpected right brace '}'.
378
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379=item Bad filehandle: %s
380
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381(F) A symbol was passed to something wanting a filehandle, but the
382symbol has no filehandle associated with it. Perhaps you didn't do an
383open(), or did it in another package.
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384
385=item Bad free() ignored
386
be771a83 387(S malloc) An internal routine called free() on something that had never
fa816bf3 388been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 389setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 390
9ea8bc6d 391This message can be seen quite often with DB_File on systems with "hard"
6903afa2 392dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 393which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 394
aa689395
PP
395=item Bad hash
396
397(P) One of the internal hash routines was passed a null HV pointer.
398
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399=item Badly placed ()'s
400
401(A) You've accidentally run your script through B<csh> instead
402of Perl. Check the #! line, or manually feed your script into
403Perl yourself.
404
a7cb8dae 405=item Bad name after %s
a0d0e21e 406
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407(F) You started to name a symbol by using a package prefix, and then
408didn't finish the symbol. In particular, you can't interpolate outside
409of quotes, so
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410
411 $var = 'myvar';
412 $sym = mypack::$var;
413
414is not the same as
415
416 $var = 'myvar';
417 $sym = "mypack::$var";
418
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419=item Bad plugin affecting keyword '%s'
420
421(F) An extension using the keyword plugin mechanism violated the
422plugin API.
423
4ad56ec9
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424=item Bad realloc() ignored
425
6903afa2
FC
426(S malloc) An internal routine called realloc() on something that
427had never been malloc()ed in the first place. Mandatory, but can
428be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 429
a0d0e21e
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430=item Bad symbol for array
431
432(P) An internal request asked to add an array entry to something that
433wasn't a symbol table entry.
434
4df3f177
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435=item Bad symbol for dirhandle
436
437(P) An internal request asked to add a dirhandle entry to something
438that wasn't a symbol table entry.
439
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440=item Bad symbol for filehandle
441
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442(P) An internal request asked to add a filehandle entry to something
443that wasn't a symbol table entry.
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444
445=item Bad symbol for hash
446
447(P) An internal request asked to add a hash entry to something that
448wasn't a symbol table entry.
449
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450=item Bareword found in conditional
451
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452(W bareword) The compiler found a bareword where it expected a
453conditional, which often indicates that an || or && was parsed as part
454of the last argument of the previous construct, for example:
34d09196
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455
456 open FOO || die;
457
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458It may also indicate a misspelled constant that has been interpreted as
459a bareword:
34d09196
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460
461 use constant TYPO => 1;
462 if (TYOP) { print "foo" }
463
464The C<strict> pragma is useful in avoiding such errors.
465
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466=item Bareword "%s" not allowed while "strict subs" in use
467
468(F) With "strict subs" in use, a bareword is only allowed as a
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469subroutine identifier, in curly brackets or to the left of the "=>"
470symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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471
472=item Bareword "%s" refers to nonexistent package
473
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474(W bareword) You used a qualified bareword of the form C<Foo::>, but the
475compiler saw no other uses of that namespace before that point. Perhaps
476you need to predeclare a package?
6df41af2 477
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478=item BEGIN failed--compilation aborted
479
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480(F) An untrapped exception was raised while executing a BEGIN
481subroutine. Compilation stops immediately and the interpreter is
482exited.
a0d0e21e 483
68dc0745
PP
484=item BEGIN not safe after errors--compilation aborted
485
486(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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487implies a C<BEGIN {}>) after one or more compilation errors had already
488occurred. Since the intended environment for the C<BEGIN {}> could not
489be guaranteed (due to the errors), and since subsequent code likely
490depends on its correct operation, Perl just gave up.
68dc0745 491
c782d7ee 492=item \%d better written as $%d
6df41af2 493
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494(W syntax) Outside of patterns, backreferences live on as variables.
495The use of backslashes is grandfathered on the right-hand side of a
496substitution, but stylistically it's better to use the variable form
497because other Perl programmers will expect it, and it works better if
498there are more than 9 backreferences.
6df41af2 499
252aa082
JH
500=item Binary number > 0b11111111111111111111111111111111 non-portable
501
e476b1b5 502(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
503(4294967295) and therefore non-portable between systems. See
504L<perlport> for more on portability concerns.
252aa082 505
69282e91 506=item bind() on closed socket %s
a0d0e21e 507
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508(W closed) You tried to do a bind on a closed socket. Did you forget to
509check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 510
c289d2f7
JH
511=item binmode() on closed filehandle %s
512
513(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 514Check your control flow and number of arguments.
c289d2f7 515
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FC
516=item "\b{" is deprecated; use "\b\{" or "\b[{]" instead in regex; marked
517by S<<-- HERE> in m/%s/
f866a7cd 518
e0e4a6e3
FC
519=item "\B{" is deprecated; use "\B\{" or "\B[{]" instead in regex; marked
520by S<<-- HERE> in m/%s/
f866a7cd 521
3c664d1a 522(D deprecated) Use of an unescaped "{" immediately following
a38411bc
FC
523a C<\b> or C<\B> is now deprecated so as to reserve its use for Perl
524itself in a future release. You can either precede the brace
525with a backslash, or enclose it in square brackets; the latter
526is the way to go if the pattern delimiters are C<{}>.
f866a7cd 527
c5a0f51a
JH
528=item Bit vector size > 32 non-portable
529
e476b1b5 530(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 531
043c750c 532=item Bizarre copy of %s
4633a7c4 533
be771a83 534(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 535copiable.
4633a7c4 536
5a25739d
FC
537=item Bizarre SvTYPE [%d]
538
434f489b 539(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
540encountered an invalid data type.
541
f675dbe5
CB
542=item Buffer overflow in prime_env_iter: %s
543
be771a83
GS
544(W internal) A warning peculiar to VMS. While Perl was preparing to
545iterate over %ENV, it encountered a logical name or symbol definition
546which was too long, so it was truncated to the string shown.
f675dbe5 547
a0d0e21e
LW
548=item Callback called exit
549
4929bf7b 550(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
551exited by calling exit.
552
6df41af2 553=item %s() called too early to check prototype
f675dbe5 554
be771a83
GS
555(W prototype) You've called a function that has a prototype before the
556parser saw a definition or declaration for it, and Perl could not check
557that the call conforms to the prototype. You need to either add an
558early prototype declaration for the subroutine in question, or move the
559subroutine definition ahead of the call to get proper prototype
560checking. Alternatively, if you are certain that you're calling the
561function correctly, you may put an ampersand before the name to avoid
562the warning. See L<perlsub>.
f675dbe5 563
49704364 564=item Cannot compress integer in pack
0258719b
NC
565
566(F) An argument to pack("w",...) was too large to compress. The BER
567compressed integer format can only be used with positive integers, and you
568attempted to compress Infinity or a very large number (> 1e308).
569See L<perlfunc/pack>.
570
49704364 571=item Cannot compress negative numbers in pack
0258719b
NC
572
573(F) An argument to pack("w",...) was negative. The BER compressed integer
574format can only be used with positive integers. See L<perlfunc/pack>.
575
5c1f4d79
NC
576=item Cannot convert a reference to %s to typeglob
577
6903afa2
FC
578(F) You manipulated Perl's symbol table directly, stored a reference
579in it, then tried to access that symbol via conventional Perl syntax.
580The access triggers Perl to autovivify that typeglob, but it there is
581no legal conversion from that type of reference to a typeglob.
5c1f4d79 582
4040665a 583=item Cannot copy to %s
ba2fdce6
NC
584
585(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 586be directly assigned to.
ba2fdce6 587
b5d97229
RGS
588=item Cannot find encoding "%s"
589
590(S io) You tried to apply an encoding that did not exist to a filehandle,
591either with open() or binmode().
592
7355df7e
FC
593=item Cannot set tied @DB::args
594
595(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
596is not supported. (Before this error was added, it used to crash.)
597
ce65bc73
FC
598=item Cannot tie unreifiable array
599
600(P) You somehow managed to call C<tie> on an array that does not
601keep a reference count on its arguments and cannot be made to
602do so. Such arrays are not even supposed to be accessible to
603Perl code, but are only used internally.
604
96ebfdd7
RK
605=item Can only compress unsigned integers in pack
606
607(F) An argument to pack("w",...) was not an integer. The BER compressed
608integer format can only be used with positive integers, and you attempted
609to compress something else. See L<perlfunc/pack>.
610
a0d0e21e
LW
611=item Can't bless non-reference value
612
613(F) Only hard references may be blessed. This is how Perl "enforces"
614encapsulation of objects. See L<perlobj>.
615
dc57907a
RGS
616=item Can't "break" in a loop topicalizer
617
0d863452 618(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 619a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
620
621=item Can't "break" outside a given block
dc57907a 622
0d863452
RH
623(F) You called C<break>, but you're not inside a C<given> block.
624
6df41af2
GS
625=item Can't call method "%s" on an undefined value
626
627(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
628object reference or package name contains an undefined value. Something
629like this will reproduce the error:
6df41af2
GS
630
631 $BADREF = undef;
632 process $BADREF 1,2,3;
633 $BADREF->process(1,2,3);
634
a0d0e21e
LW
635=item Can't call method "%s" on unblessed reference
636
54310121 637(F) A method call must know in what package it's supposed to run. It
be771a83
GS
638ordinarily finds this out from the object reference you supply, but you
639didn't supply an object reference in this case. A reference isn't an
640object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
641
642=item Can't call method "%s" without a package or object reference
643
644(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
645object reference or package name contains an expression that returns a
646defined value which is neither an object reference nor a package name.
72b5445b
GS
647Something like this will reproduce the error:
648
649 $BADREF = 42;
650 process $BADREF 1,2,3;
651 $BADREF->process(1,2,3);
652
dfe378f1
FC
653=item Can't call mro_isa_changed_in() on anonymous symbol table
654
655(P) Perl got confused as to whether a hash was a plain hash or a
656symbol table hash when trying to update @ISA caches.
657
2bf7e7b2
FC
658=item Can't call mro_method_changed_in() on anonymous symbol table
659
660(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
661not attached to the symbol table.
662
a0d0e21e
LW
663=item Can't chdir to %s
664
f703fc96 665(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
666that you can chdir to, possibly because it doesn't exist.
667
0545a864 668=item Can't check filesystem of script "%s" for nosuid
104d25b7 669
be771a83
GS
670(P) For some reason you can't check the filesystem of the script for
671nosuid.
104d25b7 672
22e74366 673=item Can't coerce %s to %s in %s
a0d0e21e
LW
674
675(F) Certain types of SVs, in particular real symbol table entries
55497cff 676(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
677say things like:
678
679 *foo += 1;
680
681You CAN say
682
683 $foo = *foo;
684 $foo += 1;
685
686but then $foo no longer contains a glob.
687
0d863452 688=item Can't "continue" outside a when block
dc57907a 689
0d863452
RH
690(F) You called C<continue>, but you're not inside a C<when>
691or C<default> block.
692
a0d0e21e
LW
693=item Can't create pipe mailbox
694
be771a83
GS
695(P) An error peculiar to VMS. The process is suffering from exhausted
696quotas or other plumbing problems.
a0d0e21e 697
eb64745e
GS
698=item Can't declare %s in "%s"
699
30c282f6
NC
700(F) Only scalar, array, and hash variables may be declared as "my", "our" or
701"state" variables. They must have ordinary identifiers as names.
a0d0e21e 702
fc7debfb
FC
703=item Can't "default" outside a topicalizer
704
705(F) You have used a C<default> block that is neither inside a
706C<foreach> loop nor a C<given> block. (Note that this error is
707issued on exit from the C<default> block, so you won't get the
708error if you use an explicit C<continue>.)
709
6df41af2
GS
710=item Can't do inplace edit: %s is not a regular file
711
be771a83 712(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 713a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 714
a0d0e21e
LW
715=item Can't do inplace edit on %s: %s
716
be771a83
GS
717(S inplace) The creation of the new file failed for the indicated
718reason.
a0d0e21e 719
54310121 720=item Can't do inplace edit without backup
a0d0e21e 721
be771a83
GS
722(F) You're on a system such as MS-DOS that gets confused if you try
723reading from a deleted (but still opened) file. You have to say
724C<-i.bak>, or some such.
a0d0e21e 725
10f9c03d 726=item Can't do inplace edit: %s would not be unique
a0d0e21e 727
e476b1b5 728(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
729characters and Perl was unable to create a unique filename during
730inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 731
a0d0e21e
LW
732=item Can't do waitpid with flags
733
be771a83
GS
734(F) This machine doesn't have either waitpid() or wait4(), so only
735waitpid() without flags is emulated.
a0d0e21e 736
a0d0e21e
LW
737=item Can't emulate -%s on #! line
738
be771a83
GS
739(F) The #! line specifies a switch that doesn't make sense at this
740point. For example, it'd be kind of silly to put a B<-x> on the #!
741line.
a0d0e21e 742
1109a392
MHM
743=item Can't %s %s-endian %ss on this platform
744
745(F) Your platform's byte-order is neither big-endian nor little-endian,
746or it has a very strange pointer size. Packing and unpacking big- or
747little-endian floating point values and pointers may not be possible.
748See L<perlfunc/pack>.
749
a0d0e21e
LW
750=item Can't exec "%s": %s
751
d1be9408 752(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
753named program for the indicated reason. Typical reasons include: the
754permissions were wrong on the file, the file wasn't found in
755C<$ENV{PATH}>, the executable in question was compiled for another
756architecture, or the #! line in a script points to an interpreter that
757can't be run for similar reasons. (Or maybe your system doesn't support
758#! at all.)
a0d0e21e
LW
759
760=item Can't exec %s
761
be771a83
GS
762(F) Perl was trying to execute the indicated program for you because
763that's what the #! line said. If that's not what you wanted, you may
764need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
765
766=item Can't execute %s
767
be771a83
GS
768(F) You used the B<-S> switch, but the copies of the script to execute
769found in the PATH did not have correct permissions.
2a92aaa0 770
6df41af2 771=item Can't find an opnumber for "%s"
2a92aaa0 772
be771a83
GS
773(F) A string of a form C<CORE::word> was given to prototype(), but there
774is no builtin with the name C<word>.
6df41af2 775
56ca2fc0
JH
776=item Can't find %s character property "%s"
777
778(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 779could not be found. Maybe you misspelled the name of the property?
e1b711da 780See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 781for a complete list of available official properties.
56ca2fc0 782
6df41af2
GS
783=item Can't find label %s
784
be771a83
GS
785(F) You said to goto a label that isn't mentioned anywhere that it's
786possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
787
788=item Can't find %s on PATH
789
be771a83
GS
790(F) You used the B<-S> switch, but the script to execute could not be
791found in the PATH.
a0d0e21e 792
6df41af2 793=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 794
be771a83
GS
795(F) You used the B<-S> switch, but the script to execute could not be
796found in the PATH, or at least not with the correct permissions. The
797script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
798
799=item Can't find string terminator %s anywhere before EOF
800
be771a83
GS
801(F) Perl strings can stretch over multiple lines. This message means
802that the closing delimiter was omitted. Because bracketed quotes count
803nesting levels, the following is missing its final parenthesis:
a0d0e21e 804
fb73857a
PP
805 print q(The character '(' starts a side comment.);
806
97b3d10f 807If you're getting this error from a here-document, you may have
b6b8cb97
FC
808included unseen whitespace before or after your closing tag or there
809may not be a linebreak after it. A good programmer's editor will have
810a way to help you find these characters (or lack of characters). See
811L<perlop> for the full details on here-documents.
a0d0e21e 812
660a4616
ST
813=item Can't find Unicode property definition "%s"
814
5f8ad6b6
FC
815(F) You may have tried to use C<\p> which means a Unicode
816property (for example C<\p{Lu}> matches all uppercase
fa816bf3 817letters). If you did mean to use a Unicode property, see
e1b711da 818L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 819for a complete list of available properties. If you didn't
fa816bf3
FC
820mean to use a Unicode property, escape the C<\p>, either by
821C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 822until C<\E>).
660a4616 823
b3647a36 824=item Can't fork: %s
a0d0e21e 825
be771a83
GS
826(F) A fatal error occurred while trying to fork while opening a
827pipeline.
a0d0e21e 828
b3647a36
SR
829=item Can't fork, trying again in 5 seconds
830
c973c02e 831(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
832after five seconds.
833
748a9306
LW
834=item Can't get filespec - stale stat buffer?
835
be771a83
GS
836(S) A warning peculiar to VMS. This arises because of the difference
837between access checks under VMS and under the Unix model Perl assumes.
838Under VMS, access checks are done by filename, rather than by bits in
839the stat buffer, so that ACLs and other protections can be taken into
840account. Unfortunately, Perl assumes that the stat buffer contains all
841the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 842the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
843the device name and FID present in the stat buffer, but this works only
844if you haven't made a subsequent call to the CRTL stat() routine,
845because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
846appears, the name lookup failed, and the access-checking routine gave up
847and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
848routine knows about the Perl C<stat> operator and file tests, so you
849shouldn't ever see this warning in response to a Perl command; it arises
850only if some internal code takes stat buffers lightly.)
748a9306 851
a0d0e21e
LW
852=item Can't get pipe mailbox device name
853
be771a83
GS
854(P) An error peculiar to VMS. After creating a mailbox to act as a
855pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
856
857=item Can't get SYSGEN parameter value for MAXBUF
858
748a9306
LW
859(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
860mailbox buffers to be, and didn't get an answer.
a0d0e21e 861
6df41af2 862=item Can't "goto" into the middle of a foreach loop
a0d0e21e 863
be771a83
GS
864(F) A "goto" statement was executed to jump into the middle of a foreach
865loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
866
867=item Can't "goto" out of a pseudo block
868
be771a83
GS
869(F) A "goto" statement was executed to jump out of what might look like
870a block, except that it isn't a proper block. This usually occurs if
871you tried to jump out of a sort() block or subroutine, which is a no-no.
872See L<perlfunc/goto>.
a0d0e21e 873
5a25739d
FC
874=item Can't goto subroutine from an eval-%s
875
876(F) The "goto subroutine" call can't be used to jump out of an eval
877"string" or block.
878
9850bf21 879=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 880
9850bf21
RH
881(F) The "goto subroutine" call can't be used to jump out of the
882comparison sub for a sort(), or from a similar callback (such
883as the reduce() function in List::Util).
884
6df41af2
GS
885=item Can't goto subroutine outside a subroutine
886
be771a83
GS
887(F) The deeply magical "goto subroutine" call can only replace one
888subroutine call for another. It can't manufacture one out of whole
889cloth. In general you should be calling it out of only an AUTOLOAD
890routine anyway. See L<perlfunc/goto>.
6df41af2 891
0b5b802d
GS
892=item Can't ignore signal CHLD, forcing to default
893
be771a83
GS
894(W signal) Perl has detected that it is being run with the SIGCHLD
895signal (sometimes known as SIGCLD) disabled. Since disabling this
896signal will interfere with proper determination of exit status of child
897processes, Perl has reset the signal to its default value. This
898situation typically indicates that the parent program under which Perl
899may be running (e.g. cron) is being very careless.
0b5b802d 900
e2c0f81f
DG
901=item Can't kill a non-numeric process ID
902
903(F) Process identifiers must be (signed) integers. It is a fatal error to
904attempt to kill() an undefined, empty-string or otherwise non-numeric
905process identifier.
906
6df41af2 907=item Can't "last" outside a loop block
4633a7c4 908
6df41af2 909(F) A "last" statement was executed to break out of the current block,
be771a83
GS
910except that there's this itty bitty problem called there isn't a current
911block. Note that an "if" or "else" block doesn't count as a "loopish"
912block, as doesn't a block given to sort(), map() or grep(). You can
913usually double the curlies to get the same effect though, because the
914inner curlies will be considered a block that loops once. See
915L<perlfunc/last>.
4633a7c4 916
2c7d6b9c
RGS
917=item Can't linearize anonymous symbol table
918
919(F) Perl tried to calculate the method resolution order (MRO) of a
920package, but failed because the package stash has no name.
921
b8170e59
JB
922=item Can't load '%s' for module %s
923
6903afa2
FC
924(F) The module you tried to load failed to load a dynamic extension.
925This may either mean that you upgraded your version of perl to one
926that is incompatible with your old dynamic extensions (which is known
927to happen between major versions of perl), or (more likely) that your
928dynamic extension was built against an older version of the library
929that is installed on your system. You may need to rebuild your old
930dynamic extensions.
b8170e59 931
748a9306
LW
932=item Can't localize lexical variable %s
933
2ba9eb46 934(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
935lexical variable using "my" or "state". This is not allowed. If you
936want to localize a package variable of the same name, qualify it with
937the package name.
748a9306 938
6df41af2 939=item Can't localize through a reference
4727527e 940
6df41af2
GS
941(F) You said something like C<local $$ref>, which Perl can't currently
942handle, because when it goes to restore the old value of whatever $ref
be771a83 943pointed to after the scope of the local() is finished, it can't be sure
64977eb6 944that $ref will still be a reference.
4727527e 945
ea071790 946=item Can't locate %s
ec889f3a 947
fa816bf3
FC
948(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
949Perl looks for the file in all the locations mentioned in @INC, unless
950the file name included the full path to the file. Perhaps you need
951to set the PERL5LIB or PERL5OPT environment variable to say where the
952extra library is, or maybe the script needs to add the library name
be771a83
GS
953to @INC. Or maybe you just misspelled the name of the file. See
954L<perlfunc/require> and L<lib>.
a0d0e21e 955
6df41af2
GS
956=item Can't locate auto/%s.al in @INC
957
be771a83
GS
958(F) A function (or method) was called in a package which allows
959autoload, but there is no function to autoload. Most probable causes
960are a misprint in a function/method name or a failure to C<AutoSplit>
961the file, say, by doing C<make install>.
6df41af2 962
b8170e59
JB
963=item Can't locate loadable object for module %s in @INC
964
965(F) The module you loaded is trying to load an external library, like
d70d8e57 966for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
967unable to locate this library. See L<DynaLoader>.
968
a0d0e21e
LW
969=item Can't locate object method "%s" via package "%s"
970
971(F) You called a method correctly, and it correctly indicated a package
972functioning as a class, but that package doesn't define that particular
2ba9eb46 973method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
974
975=item Can't locate package %s for @%s::ISA
976
be771a83
GS
977(W syntax) The @ISA array contained the name of another package that
978doesn't seem to exist.
a0d0e21e 979
2f7da168
RK
980=item Can't locate PerlIO%s
981
982(F) You tried to use in open() a PerlIO layer that does not exist,
983e.g. open(FH, ">:nosuchlayer", "somefile").
984
f4ad53f4 985=item Can't make list assignment to %ENV on this system
3e3baf6d 986
be771a83
GS
987(F) List assignment to %ENV is not supported on some systems, notably
988VMS.
3e3baf6d 989
cd40cd58
NC
990=item Can't make loaded symbols global on this platform while loading %s
991
ff9c1ae8 992(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
993that symbols from the stated file are made available globally within the
994process, but that functionality is not available on this platform. Whilst
995the module likely will still work, this may prevent the perl interpreter
996from loading other XS-based extensions which need to link directly to
997functions defined in the C or XS code in the stated file.
998
a0d0e21e
LW
999=item Can't modify %s in %s
1000
be771a83
GS
1001(F) You aren't allowed to assign to the item indicated, or otherwise try
1002to change it, such as with an auto-increment.
a0d0e21e 1003
54310121 1004=item Can't modify nonexistent substring
a0d0e21e
LW
1005
1006(P) The internal routine that does assignment to a substr() was handed
1007a NULL.
1008
6df41af2
GS
1009=item Can't modify non-lvalue subroutine call
1010
1011(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1012such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1013
5f05dabc 1014=item Can't msgrcv to read-only var
a0d0e21e 1015
5f05dabc 1016(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1017buffer.
1018
6df41af2
GS
1019=item Can't "next" outside a loop block
1020
1021(F) A "next" statement was executed to reiterate the current block, but
1022there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1023count as a "loopish" block, as doesn't a block given to sort(), map() or
1024grep(). You can usually double the curlies to get the same effect
1025though, because the inner curlies will be considered a block that loops
1026once. See L<perlfunc/next>.
6df41af2 1027
46fa9b26
FC
1028=item Can't open %s
1029
1030(F) You tried to run a perl built with MAD support with
1031the PERL_XMLDUMP environment variable set, but the file
1032named by that variable could not be opened.
1033
a0d0e21e
LW
1034=item Can't open %s: %s
1035
c47ff5f1 1036(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1037filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1038switches, or explicitly, failed for the indicated reason. Usually
1039this is because you don't have read permission for a file which
1040you named on the command line.
1041
1042(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1043your operating system's equivalent) could not be opened.
a0d0e21e 1044
9a869a14
RGS
1045=item Can't open a reference
1046
1047(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1048using the 3-arg open() syntax:
9a869a14
RGS
1049
1050 open FH, '>', $ref;
1051
1052but your version of perl is compiled without perlio, and this form of
1053open is not supported.
1054
a0d0e21e
LW
1055=item Can't open bidirectional pipe
1056
be771a83
GS
1057(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1058You can try any of several modules in the Perl library to do this, such
1059as IPC::Open2. Alternately, direct the pipe's output to a file using
1060">", and then read it in under a different file handle.
a0d0e21e 1061
748a9306
LW
1062=item Can't open error file %s as stderr
1063
be771a83
GS
1064(F) An error peculiar to VMS. Perl does its own command line
1065redirection, and couldn't open the file specified after '2>' or '2>>' on
1066the command line for writing.
748a9306
LW
1067
1068=item Can't open input file %s as stdin
1069
be771a83
GS
1070(F) An error peculiar to VMS. Perl does its own command line
1071redirection, and couldn't open the file specified after '<' on the
1072command line for reading.
748a9306
LW
1073
1074=item Can't open output file %s as stdout
1075
be771a83
GS
1076(F) An error peculiar to VMS. Perl does its own command line
1077redirection, and couldn't open the file specified after '>' or '>>' on
1078the command line for writing.
748a9306
LW
1079
1080=item Can't open output pipe (name: %s)
1081
be771a83
GS
1082(P) An error peculiar to VMS. Perl does its own command line
1083redirection, and couldn't open the pipe into which to send data destined
1084for stdout.
748a9306 1085
3b1cf97d 1086=item Can't open perl script "%s": %s
a0d0e21e
LW
1087
1088(F) The script you specified can't be opened for the indicated reason.
1089
fa3aa65a
JC
1090If you're debugging a script that uses #!, and normally relies on the
1091shell's $PATH search, the -S option causes perl to do that search, so
1092you don't have to type the path or C<`which $scriptname`>.
1093
6df41af2
GS
1094=item Can't read CRTL environ
1095
1096(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1097from the CRTL's internal environment array and discovered the array was
1098missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1099or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1100searched.
6df41af2 1101
6df41af2
GS
1102=item Can't "redo" outside a loop block
1103
1104(F) A "redo" statement was executed to restart the current block, but
1105there isn't a current block. Note that an "if" or "else" block doesn't
1106count as a "loopish" block, as doesn't a block given to sort(), map()
1107or grep(). You can usually double the curlies to get the same effect
1108though, because the inner curlies will be considered a block that
1109loops once. See L<perlfunc/redo>.
1110
64977eb6 1111=item Can't remove %s: %s, skipping file
10f9c03d 1112
be771a83
GS
1113(S inplace) You requested an inplace edit without creating a backup
1114file. Perl was unable to remove the original file to replace it with
1115the modified file. The file was left unmodified.
10f9c03d 1116
a0d0e21e
LW
1117=item Can't rename %s to %s: %s, skipping file
1118
e476b1b5 1119(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1120probably because you don't have write permission to the directory.
a0d0e21e 1121
748a9306
LW
1122=item Can't reopen input pipe (name: %s) in binary mode
1123
be771a83
GS
1124(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1125to reopen it to accept binary data. Alas, it failed.
748a9306 1126
4f12ec0e
FC
1127=item Can't reset %ENV on this system
1128
1129(F) You called C<reset('E')> or similar, which tried to reset
1130all variables in the current package beginning with "E". In
1131the main package, that includes %ENV. Resetting %ENV is not
1132supported on some systems, notably VMS.
1133
fe13d51d 1134=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1135
1fa582fa
FC
1136(F)(P) Error resolving overloading specified by a method name (as
1137opposed to a subroutine reference): no such method callable via the
1138package. If the method name is C<???>, this is an internal error.
6df41af2 1139
cd06dffe
GS
1140=item Can't return %s from lvalue subroutine
1141
be771a83
GS
1142(F) Perl detected an attempt to return illegal lvalues (such as
1143temporary or readonly values) from a subroutine used as an lvalue. This
1144is not allowed.
cd06dffe 1145
96ebfdd7
RK
1146=item Can't return outside a subroutine
1147
1148(F) The return statement was executed in mainline code, that is, where
1149there was no subroutine call to return out of. See L<perlsub>.
1150
78f9721b
SM
1151=item Can't return %s to lvalue scalar context
1152
6903afa2
FC
1153(F) You tried to return a complete array or hash from an lvalue
1154subroutine, but you called the subroutine in a way that made Perl
1155think you meant to return only one value. You probably meant to
1156write parentheses around the call to the subroutine, which tell
1157Perl that the call should be in list context.
78f9721b 1158
a0d0e21e
LW
1159=item Can't stat script "%s"
1160
be771a83
GS
1161(P) For some reason you can't fstat() the script even though you have it
1162open already. Bizarre.
a0d0e21e 1163
a0d0e21e
LW
1164=item Can't take log of %g
1165
fb73857a 1166(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1167negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1168standard with Perl, though, if you really want to do that for the
1169negative numbers.
a0d0e21e
LW
1170
1171=item Can't take sqrt of %g
1172
1173(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1174negative number. There's a Math::Complex package that comes standard
1175with Perl, though, if you really want to do that.
a0d0e21e
LW
1176
1177=item Can't undef active subroutine
1178
1179(F) You can't undefine a routine that's currently running. You can,
1180however, redefine it while it's running, and you can even undef the
1181redefined subroutine while the old routine is running. Go figure.
1182
c81225bc 1183=item Can't upgrade %s (%d) to %d
a0d0e21e 1184
be771a83
GS
1185(P) The internal sv_upgrade routine adds "members" to an SV, making it
1186into a more specialized kind of SV. The top several SV types are so
1187specialized, however, that they cannot be interconverted. This message
1188indicates that such a conversion was attempted.
a0d0e21e 1189
6651ba0b
FC
1190=item Can't use '%c' after -mname
1191
1192(F) You tried to call perl with the B<-m> switch, but you put something
1193other than "=" after the module name.
1194
1db89ea5
BS
1195=item Can't use anonymous symbol table for method lookup
1196
e27ad1f2 1197(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1198table that doesn't have a name. Symbol tables can become anonymous
1199for example by undefining stashes: C<undef %Some::Package::>.
1200
96ebfdd7
RK
1201=item Can't use an undefined value as %s reference
1202
1203(F) A value used as either a hard reference or a symbolic reference must
1204be a defined value. This helps to delurk some insidious errors.
1205
6df41af2
GS
1206=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1207
be771a83
GS
1208(F) Only hard references are allowed by "strict refs". Symbolic
1209references are disallowed. See L<perlref>.
6df41af2 1210
90b75b61 1211=item Can't use %! because Errno.pm is not available
1d2dff63 1212
20561843 1213(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1214Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1215provide symbolic names for C<$!> errno values.
1216
1109a392
MHM
1217=item Can't use both '<' and '>' after type '%c' in %s
1218
1219(F) A type cannot be forced to have both big-endian and little-endian
1220byte-order at the same time, so this combination of modifiers is not
1221allowed. See L<perlfunc/pack>.
1222
6df41af2
GS
1223=item Can't use %s for loop variable
1224
be771a83
GS
1225(F) Only a simple scalar variable may be used as a loop variable on a
1226foreach.
6df41af2 1227
aab6a793 1228=item Can't use global %s in "%s"
6df41af2 1229
be771a83
GS
1230(F) You tried to declare a magical variable as a lexical variable. This
1231is not allowed, because the magic can be tied to only one location
1232(namely the global variable) and it would be incredibly confusing to
1233have variables in your program that looked like magical variables but
6df41af2
GS
1234weren't.
1235
6d3b25aa
RGS
1236=item Can't use '%c' in a group with different byte-order in %s
1237
1238(F) You attempted to force a different byte-order on a type
1239that is already inside a group with a byte-order modifier.
1240For example you cannot force little-endianness on a type that
1241is inside a big-endian group.
1242
c07a80fd
PP
1243=item Can't use "my %s" in sort comparison
1244
1245(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1246You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1247and the variable had earlier been declared as a lexical variable.
1248Either qualify the sort variable with the package name, or rename the
1249lexical variable.
1250
a0d0e21e
LW
1251=item Can't use %s ref as %s ref
1252
1253(F) You've mixed up your reference types. You have to dereference a
1254reference of the type needed. You can use the ref() function to
1255test the type of the reference, if need be.
1256
748a9306 1257=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1258
5e634d20
FC
1259=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1260
b41bf23f
FC
1261(F) You've told Perl to dereference a string, something which
1262C<use strict> blocks to prevent it happening accidentally. See
1263L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1264in a double-quoted string immediately before interpolating a variable,
1265for example in C<"user @$twitter_id">, which says to treat the contents
1266of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1267symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1268
748a9306
LW
1269=item Can't use subscript on %s
1270
1271(F) The compiler tried to interpret a bracketed expression as a
1272subscript. But to the left of the brackets was an expression that
209e7cf1 1273didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1274
6df41af2
GS
1275=item Can't use \%c to mean $%c in expression
1276
75b44862
GS
1277(W syntax) In an ordinary expression, backslash is a unary operator that
1278creates a reference to its argument. The use of backslash to indicate a
1279backreference to a matched substring is valid only as part of a regular
be771a83
GS
1280expression pattern. Trying to do this in ordinary Perl code produces a
1281value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1282instead.
6df41af2 1283
810b8aa5
GS
1284=item Can't weaken a nonreference
1285
1286(F) You attempted to weaken something that was not a reference. Only
1287references can be weakened.
1288
fc7debfb
FC
1289=item Can't "when" outside a topicalizer
1290
1291(F) You have used a when() block that is neither inside a C<foreach>
1292loop nor a C<given> block. (Note that this error is issued on exit
1293from the C<when> block, so you won't get the error if the match fails,
1294or if you use an explicit C<continue>.)
1295
5f05dabc 1296=item Can't x= to read-only value
a0d0e21e 1297
be771a83
GS
1298(F) You tried to repeat a constant value (often the undefined value)
1299with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1300Perhaps you need to copy the value to a temporary, and repeat that.
1301
4a68bf9d 1302=item Character following "\c" must be ASCII
f9d13529 1303
3c664d1a 1304(F)(D deprecated, syntax) In C<\cI<X>>, I<X> must be an ASCII character.
675fa9ff
FC
1305It is planned to make this fatal in all instances in Perl v5.20. In
1306the cases where it isn't fatal, the character this evaluates to is
17a3df4c
KW
1307derived by exclusive or'ing the code point of this character with 0x40.
1308
c9faaf04
KW
1309Note that non-alphabetic ASCII characters are discouraged here as well,
1310and using non-printable ones will be deprecated starting in v5.18.
f9d13529 1311
f337b084 1312=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1313
1314(W pack) You said
1315
1316 pack("C", $x)
1317
1318where $x is either less than 0 or more than 255; the C<"C"> format is
1319only for encoding native operating system characters (ASCII, EBCDIC,
1320and so on) and not for Unicode characters, so Perl behaved as if you meant
1321
1322 pack("C", $x & 255)
1323
1324If you actually want to pack Unicode codepoints, use the C<"U"> format
1325instead.
1326
f337b084 1327=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1328
1329(W pack) You said
1330
1331 pack("c", $x)
1332
1333where $x is either less than -128 or more than 127; the C<"c"> format
1334is only for encoding native operating system characters (ASCII, EBCDIC,
1335and so on) and not for Unicode characters, so Perl behaved as if you meant
1336
1337 pack("c", $x & 255);
1338
1339If you actually want to pack Unicode codepoints, use the C<"U"> format
1340instead.
1341
f337b084
TH
1342=item Character in '%c' format wrapped in unpack
1343
1344(W unpack) You tried something like
1345
1346 unpack("H", "\x{2a1}")
1347
1a147d38 1348where the format expects to process a byte (a character with a value
6903afa2
FC
1349below 256), but a higher value was provided instead. Perl uses the
1350value modulus 256 instead, as if you had provided:
f337b084
TH
1351
1352 unpack("H", "\x{a1}")
1353
5a25739d
FC
1354=item Character in 'W' format wrapped in pack
1355
1356(W pack) You said
1357
1358 pack("U0W", $x)
1359
1360where $x is either less than 0 or more than 255. However, C<U0>-mode
1361expects all values to fall in the interval [0, 255], so Perl behaved
1362as if you meant:
1363
1364 pack("U0W", $x & 255)
1365
f337b084
TH
1366=item Character(s) in '%c' format wrapped in pack
1367
1368(W pack) You tried something like
1369
1370 pack("u", "\x{1f3}b")
1371
1a147d38 1372where the format expects to process a sequence of bytes (character with a
6903afa2 1373value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1374uses the character values modulus 256 instead, as if you had provided:
1375
1376 pack("u", "\x{f3}b")
1377
1378=item Character(s) in '%c' format wrapped in unpack
1379
1380(W unpack) You tried something like
1381
1382 unpack("s", "\x{1f3}b")
1383
1a147d38 1384where the format expects to process a sequence of bytes (character with a
6903afa2 1385value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1386uses the character values modulus 256 instead, as if you had provided:
1387
1388 unpack("s", "\x{f3}b")
1389
f866a7cd
FC
1390=item "\c%c" is more clearly written simply as "%s"
1391
1392(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1393non-printable characters. You used it for a printable one, which is better
1394written as simply itself, perhaps preceded by a backslash for non-word
1395characters.
1396
6651ba0b
FC
1397=item Cloning substitution context is unimplemented
1398
1399(F) Creating a new thread inside the C<s///> operator is not supported.
1400
abc7ecad
SP
1401=item closedir() attempted on invalid dirhandle %s
1402
1403(W io) The dirhandle you tried to close is either closed or not really
1404a dirhandle. Check your control flow.
1405
5a25739d
FC
1406=item close() on unopened filehandle %s
1407
1408(W unopened) You tried to close a filehandle that was never opened.
1409
541ed3a9
FC
1410=item Closure prototype called
1411
1412(F) If a closure has attributes, the subroutine passed to an attribute
1413handler is the prototype that is cloned when a new closure is created.
1414This subroutine cannot be called.
1415
49704364
LW
1416=item Code missing after '/'
1417
6903afa2
FC
1418(F) You had a (sub-)template that ends with a '/'. There must be
1419another template code following the slash. See L<perlfunc/pack>.
49704364 1420
5a25739d
FC
1421=item Code point 0x%X is not Unicode, may not be portable
1422
2d88a86a 1423(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1424of U+10FFFF.
1425
1426Perl allows strings to contain a superset of Unicode code points, up
1427to the limit of what is storable in an unsigned integer on your system,
1428but these may not be accepted by other languages/systems. At one time,
1429it was legal in some standards to have code points up to 0x7FFF_FFFF,
1430but not higher. Code points above 0xFFFF_FFFF require larger than a
143132 bit word.
0876b9a0 1432
6df41af2
GS
1433=item %s: Command not found
1434
a892b81a
FC
1435(A) You've accidentally run your script through B<csh> or another shell
1436shell instead of Perl. Check the #! line, or manually feed your script
1437into Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1438
1439 #!/usr/bin/perl -w
6df41af2 1440
7a2e2cd6
PP
1441=item Compilation failed in require
1442
1443(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1444Perl uses this generic message when none of the errors that it
1445encountered were severe enough to halt compilation immediately.
7a2e2cd6 1446
c3464db5
DD
1447=item Complex regular subexpression recursion limit (%d) exceeded
1448
be771a83
GS
1449(W regexp) The regular expression engine uses recursion in complex
1450situations where back-tracking is required. Recursion depth is limited
1451to 32766, or perhaps less in architectures where the stack cannot grow
1452arbitrarily. ("Simple" and "medium" situations are handled without
1453recursion and are not subject to a limit.) Try shortening the string
1454under examination; looping in Perl code (e.g. with C<while>) rather than
1455in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1456that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1457on I<Mastering Regular Expressions>.)
c3464db5 1458
69282e91 1459=item connect() on closed socket %s
a0d0e21e 1460
be771a83
GS
1461(W closed) You tried to do a connect on a closed socket. Did you forget
1462to check the return value of your socket() call? See
1463L<perlfunc/connect>.
a0d0e21e 1464
e21e7c6a
FC
1465=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1466
1467(F) The subroutine registered to handle constant overloading
1468(see L<overload>) or a custom charnames handler (see
1469L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1470
1471=item Constant(%s): $^H{%s} is not defined
1472
1473(F) The parser found inconsistencies while attempting to define an
1474overloaded constant. Perhaps you forgot to load the corresponding
1475L<overload> pragma?.
1476
779c5bc9
GS
1477=item Constant is not %s reference
1478
1479(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1480is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1481The message indicates the type of reference that was expected. This
be771a83 1482usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1483See L<perlsub/"Constant Functions"> and L<constant>.
1484
4cee8e80
CS
1485=item Constant subroutine %s redefined
1486
aeb94125
FC
1487(W redefine)(S) You redefined a subroutine which had previously
1488been eligible for inlining. See L<perlsub/"Constant Functions">
1489for commentary and workarounds.
4cee8e80 1490
9607fc9c
PP
1491=item Constant subroutine %s undefined
1492
be771a83
GS
1493(W misc) You undefined a subroutine which had previously been eligible
1494for inlining. See L<perlsub/"Constant Functions"> for commentary and
1495workarounds.
9607fc9c 1496
5a25739d
FC
1497=item Constant(%s) unknown
1498
1499(F) The parser found inconsistencies either while attempting
1500to define an overloaded constant, or when trying to find the
1501character name specified in the C<\N{...}> escape. Perhaps you
1502forgot to load the corresponding L<overload> pragma?.
1503
e7ea3e70
IZ
1504=item Copy method did not return a reference
1505
6903afa2 1506(F) The method which overloads "=" is buggy. See
13a2d996 1507L<overload/Copy Constructor>.
e7ea3e70 1508
4aaa4757
FC
1509=item &CORE::%s cannot be called directly
1510
1511(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1512with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1513in this package cannot yet be called that way, but must be
1514called as barewords. Something like this will work:
1515
1516 BEGIN { *shove = \&CORE::push; }
1517 shove @array, 1,2,3; # pushes on to @array
1518
6798c92b
GS
1519=item CORE::%s is not a keyword
1520
1521(F) The CORE:: namespace is reserved for Perl keywords.
1522
675fa9ff
FC
1523=item Corrupted regexp opcode %d > %d
1524
1525(P) This is either an error in Perl, or, if you're using
1526one, your L<custom regular expression engine|perlreapi>. If not the
1527latter, report the problem through the L<perlbug> utility.
1528
a0d0e21e
LW
1529=item corrupted regexp pointers
1530
1531(P) The regular expression engine got confused by what the regular
1532expression compiler gave it.
1533
1534=item corrupted regexp program
1535
be771a83
GS
1536(P) The regular expression engine got passed a regexp program without a
1537valid magic number.
a0d0e21e 1538
de42a5a9 1539=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1540
1541(P) The malloc package that comes with Perl had an internal failure.
1542
49704364
LW
1543=item Count after length/code in unpack
1544
1545(F) You had an unpack template indicating a counted-length string, but
1546you have also specified an explicit size for the string. See
1547L<perlfunc/pack>.
1548
f2cccb4c
KW
1549=for comment
1550The following are used in lib/diagnostics.t for testing two =items that
1551share the same description. Changes here need to be propagated to there
1552
6651ba0b
FC
1553=item Deep recursion on anonymous subroutine
1554
a0d0e21e
LW
1555=item Deep recursion on subroutine "%s"
1556
be771a83
GS
1557(W recursion) This subroutine has called itself (directly or indirectly)
1558100 times more than it has returned. This probably indicates an
1559infinite recursion, unless you're writing strange benchmark programs, in
1560which case it indicates something else.
a0d0e21e 1561
aad1d01f
NC
1562This threshold can be changed from 100, by recompiling the F<perl> binary,
1563setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1564
f10b0346 1565=item defined(@array) is deprecated
69794302 1566
be771a83
GS
1567(D deprecated) defined() is not usually useful on arrays because it
1568checks for an undefined I<scalar> value. If you want to see if the
64977eb6 1569array is empty, just use C<if (@array) { # not empty }> for example.
69794302 1570
f10b0346 1571=item defined(%hash) is deprecated
69794302 1572
f0ec9725
KR
1573(D deprecated) C<defined()> is not usually right on hashes and has been
1574discouraged since 5.004.
1575
1576Although C<defined %hash> is false on a plain not-yet-used hash, it
1577becomes true in several non-obvious circumstances, including iterators,
1578weak references, stash names, even remaining true after C<undef %hash>.
1579These things make C<defined %hash> fairly useless in practice.
1580
1581If a check for non-empty is what you wanted then just put it in boolean
1582context (see L<perldata/Scalar values>):
16546e45
KR
1583
1584 if (%hash) {
1585 # not empty
1586 }
1587
f0ec9725
KR
1588If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1589variable exists then that's never really been reliable, and isn't
1590a good way to enquire about the features of a package, or whether
1591it's loaded, etc.
1592
69794302 1593
e0e4a6e3
FC
1594=item (?(DEFINE)....) does not allow branches in regex; marked by
1595S<<-- HERE> in m/%s/
bcb95744 1596
6903afa2 1597(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1598most likely cause of this error is that you left out a parenthesis inside
1599of the C<....> part.
1600
9e3ec65c 1601The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1602discovered.
1603
62658f4d
PM
1604=item %s defines neither package nor VERSION--version check failed
1605
1606(F) You said something like "use Module 42" but in the Module file
1607there are neither package declarations nor a C<$VERSION>.
1608
36447869
FC
1609=item delete argument is index/value array slice, use array slice
1610
1611(F) You used index/value array slice syntax (C<%array[...]>) as
1612the argument to C<delete>. You probably meant C<@array[...]> with
1613an @ symbol instead.
1614
1615=item delete argument is key/value hash slice, use hash slice
1616
1617(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1618C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1619
0ffcbc25
FC
1620=item delete argument is not a HASH or ARRAY element or slice
1621
4a0af295 1622(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1623such as:
1624
1625 $foo{$bar}
1626 $ref->{"susie"}[12]
1627
1628or a hash or array slice, such as:
1629
1630 @foo[$bar, $baz, $xyzzy]
1631 @{$ref->[12]}{"susie", "queue"}
1632
fc36a67e
PP
1633=item Delimiter for here document is too long
1634
be771a83
GS
1635(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1636long for Perl to handle. You have to be seriously twisted to write code
1637that triggers this error.
fc36a67e 1638
6d3b25aa
RGS
1639=item Deprecated use of my() in false conditional
1640
fa816bf3
FC
1641(D deprecated) You used a declaration similar to C<my $x if 0>. There
1642has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1643not to be cleared at scope exit when its declaration includes a false
6903afa2 1644conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1645static variable. Since we intend to fix this bug, we don't want people
6903afa2 1646relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1647declaring the variable in a separate block outside the function, eg
36fb85f3 1648
6d3b25aa
RGS
1649 sub f { my $x if 0; return $x++ }
1650
1651becomes
1652
1653 { my $x; sub f { return $x++ } }
1654
ea9d9ebc 1655Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1656lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1657
1658 sub f { state $x; return $x++ }
1659
500ab966
RGS
1660=item DESTROY created new reference to dead object '%s'
1661
1662(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1663just being DESTROYed. Perl is confused, and prefers to abort rather
1664than to create a dangling reference.
500ab966 1665
3cdd684c
TP
1666=item Did not produce a valid header
1667
1668See Server error.
1669
6df41af2
GS
1670=item %s did not return a true value
1671
1672(F) A required (or used) file must return a true value to indicate that
1673it compiled correctly and ran its initialization code correctly. It's
1674traditional to end such a file with a "1;", though any true value would
1675do. See L<perlfunc/require>.
1676
cc507455 1677=item (Did you mean &%s instead?)
4633a7c4 1678
413ff9f6
FC
1679(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1680some such.
4633a7c4 1681
cc507455 1682=item (Did you mean "local" instead of "our"?)
33633739 1683
be771a83
GS
1684(W misc) Remember that "our" does not localize the declared global
1685variable. You have declared it again in the same lexical scope, which
1686seems superfluous.
33633739 1687
cc507455 1688=item (Did you mean $ or @ instead of %?)
a0d0e21e 1689
be771a83
GS
1690(W) You probably said %hash{$key} when you meant $hash{$key} or
1691@hash{@keys}. On the other hand, maybe you just meant %hash and got
1692carried away.
748a9306 1693
7e1af8bc 1694=item Died
5f05dabc
PP
1695
1696(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1697you called it with no args and C<$@> was empty.
5f05dabc 1698
3cdd684c
TP
1699=item Document contains no data
1700
1701See Server error.
1702
62658f4d
PM
1703=item %s does not define %s::VERSION--version check failed
1704
1705(F) You said something like "use Module 42" but the Module did not
943fc58e 1706define a C<$VERSION>.
62658f4d 1707
49704364
LW
1708=item '/' does not take a repeat count
1709
1710(F) You cannot put a repeat count of any kind right after the '/' code.
1711See L<perlfunc/pack>.
1712
95cb0d72
FC
1713=item Don't know how to get file name
1714
1715(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1716somehow called on another platform. This should not happen.
1717
4021c788 1718=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1719
1720(P) The internal handling of magical variables has been cursed.
1721
1722=item do_study: out of memory
1723
1724(P) This should have been caught by safemalloc() instead.
1725
6df41af2
GS
1726=item (Do you need to predeclare %s?)
1727
56da5a46
RGS
1728(S syntax) This is an educated guess made in conjunction with the message
1729"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1730name is being referenced that hasn't been declared yet. This may be
1731because of ordering problems in your file, or because of a missing
be771a83
GS
1732"sub", "package", "require", or "use" statement. If you're referencing
1733something that isn't defined yet, you don't actually have to define the
1734subroutine or package before the current location. You can use an empty
1735"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1736
ac206dc8
RGS
1737=item dump() better written as CORE::dump()
1738
1739(W misc) You used the obsolescent C<dump()> built-in function, without fully
1740qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1741
84d78eb7
YO
1742=item dump is not supported
1743
1744(F) Your machine doesn't support dump/undump.
1745
a0d0e21e
LW
1746=item Duplicate free() ignored
1747
be771a83
GS
1748(S malloc) An internal routine called free() on something that had
1749already been freed.
a0d0e21e 1750
1109a392
MHM
1751=item Duplicate modifier '%c' after '%c' in %s
1752
35f0cd76
FC
1753(W unpack) You have applied the same modifier more than once after a
1754type in a pack template. See L<perlfunc/pack>.
1109a392 1755
0953b66b
FC
1756=item each on reference is experimental
1757
0773cb3e
FC
1758(S experimental::autoderef) C<each> with a scalar argument is experimental
1759and may change or be removed in a future Perl version. If you want to
1760take the risk of using this feature, simply disable this warning:
0953b66b 1761
d401967c 1762 no warnings "experimental::autoderef";
0953b66b 1763
4633a7c4
LW
1764=item elseif should be elsif
1765
fa816bf3
FC
1766(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1767it's ugly. Your code will be interpreted as an attempt to call a method
1768named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1769unlikely to be what you want.
1770
e0e4a6e3 1771=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1772
af6f566e 1773(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1774described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1775a regular expression without specifying the property name.
ab13f0c7 1776
85ab1d1d 1777=item entering effective %s failed
5ff3f7a4 1778
85ab1d1d 1779(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1780effective uids or gids failed.
1781
c038024b
RGS
1782=item %ENV is aliased to %s
1783
1784(F) You're running under taint mode, and the C<%ENV> variable has been
1785aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1786program's environment. This is potentially insecure.
c038024b 1787
748a9306
LW
1788=item Error converting file specification %s
1789
5f05dabc 1790(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1791specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1792single form when it must operate on them directly. Either you've passed
1793an invalid file specification to Perl, or you've found a case the
1794conversion routines don't handle. Drat.
748a9306 1795
ff56e4f1
KW
1796=item Escape literal pattern white space under /x
1797
1798(D deprecated) You compiled a regular expression pattern with C</x> to
1799ignore white space, and you used, as a literal, one of the characters
1800that Perl plans to eventually treat as white space. The character must
1801be escaped somehow, or it will work differently on a future Perl that
1802does treat it as white space. The easiest way is to insert a backslash
1803immediately before it, or to enclose it with square brackets. This
1804change is to bring Perl into conformance with Unicode recommendations.
1805Here are the five characters that generate this warning:
1806U+0085 NEXT LINE,
1807U+200E LEFT-TO-RIGHT MARK,
1808U+200F RIGHT-TO-LEFT MARK,
1809U+2028 LINE SEPARATOR,
1810and
1811U+2029 PARAGRAPH SEPARATOR.
1812
ad19ef22 1813=item Eval-group in insecure regular expression
e4d48cc9 1814
be771a83
GS
1815(F) Perl detected tainted data when trying to compile a regular
1816expression that contains the C<(?{ ... })> zero-width assertion, which
1817is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1818
ad19ef22 1819=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1820
be771a83
GS
1821(F) Perl tried to compile a regular expression containing the
1822C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1823pattern contains interpolated values. Since that is a security risk,
1824it is not allowed. If you insist, you may still do this by using the
1825C<re 'eval'> pragma or by explicitly building the pattern from an
1826interpolated string at run time and using that in an eval(). See
1827L<perlre/(?{ code })>.
e4d48cc9 1828
ad19ef22 1829=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1830
be771a83
GS
1831(F) A regular expression contained the C<(?{ ... })> zero-width
1832assertion, but that construct is only allowed when the C<use re 'eval'>
1833pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1834
e0e4a6e3
FC
1835=item EVAL without pos change exceeded limit in regex; marked by
1836S<<-- HERE> in m/%s/
1a147d38
YO
1837
1838(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1839any text. Restructure the pattern so that text is consumed.
1a147d38 1840
9e3ec65c 1841The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1842discovered.
1843
fc36a67e
PP
1844=item Excessively long <> operator
1845
1846(F) The contents of a <> operator may not exceed the maximum size of a
1847Perl identifier. If you're just trying to glob a long list of
1848filenames, try using the glob() operator, or put the filenames into a
1849variable and glob that.
1850
ed9aa3b7
SG
1851=item exec? I'm not *that* kind of operating system
1852
af8bb25a 1853(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1854OS. See L<perlport>.
ed9aa3b7 1855
fe13d51d 1856=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1857
1858(F) The final summary message when a Perl compilation fails.
1859
0ffcbc25
FC
1860=item exists argument is not a HASH or ARRAY element or a subroutine
1861
4a0af295 1862(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1863subroutine with an ampersand, such as:
1864
1865 $foo{$bar}
1866 $ref->{"susie"}[12]
1867 &do_something
1868
1869=item exists argument is not a subroutine name
1870
ccfc2567
FC
1871(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1872and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1873
a0d0e21e
LW
1874=item Exiting eval via %s
1875
be771a83
GS
1876(W exiting) You are exiting an eval by unconventional means, such as a
1877goto, or a loop control statement.
e476b1b5
GS
1878
1879=item Exiting format via %s
1880
9a2ff54b 1881(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1882goto, or a loop control statement.
a0d0e21e 1883
0a753a76
PP
1884=item Exiting pseudo-block via %s
1885
be771a83
GS
1886(W exiting) You are exiting a rather special block construct (like a
1887sort block or subroutine) by unconventional means, such as a goto, or a
1888loop control statement. See L<perlfunc/sort>.
0a753a76 1889
a0d0e21e
LW
1890=item Exiting subroutine via %s
1891
be771a83
GS
1892(W exiting) You are exiting a subroutine by unconventional means, such
1893as a goto, or a loop control statement.
a0d0e21e
LW
1894
1895=item Exiting substitution via %s
1896
be771a83
GS
1897(W exiting) You are exiting a substitution by unconventional means, such
1898as a return, a goto, or a loop control statement.
a0d0e21e 1899
e0e4a6e3 1900=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1901
675fa9ff 1902(F) You wrote something like
c608e803
KW
1903
1904 (?13
1905
1906to denote a capturing group of the form
1907L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1908but omitted the C<")">.
1909
e0e4a6e3 1910=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1911
8b6fbf55
FC
1912(F) The C<(?[...])> extended character class regular expression construct
1913only allows character classes (including character class escapes like
1914C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1915containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1916This allows a regular expression containing just C<(?[...])> to be
1917interpolated. If you see this error message, then you probably
1918have some other C<(?...)> construct inside your character class. See
1919L<perlrecharclass/Extended Bracketed Character Classes>.
1920
30d9c59b
Z
1921=item Experimental subroutine signatures not enabled
1922
1923(F) To use subroutine signatures, you must first enable them:
1924
1925 no warnings "experimental:signatures";
1926 use feature "signatures";
1927 sub foo ($left, $right) { ... }
1928
6da34ecb
FC
1929=item Experimental "%s" subs not enabled
1930
1931(F) To use lexical subs, you must first enable them:
1932
1933 no warnings 'experimental::lexical_subs';
1934 use feature 'lexical_subs';
1935 my sub foo { ... }
1936
7b8d334a
GS
1937=item Explicit blessing to '' (assuming package main)
1938
be771a83
GS
1939(W misc) You are blessing a reference to a zero length string. This has
1940the effect of blessing the reference into the package main. This is
1941usually not what you want. Consider providing a default target package,
1942e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1943
6df41af2
GS
1944=item %s: Expression syntax
1945
be771a83
GS
1946(A) You've accidentally run your script through B<csh> instead of Perl.
1947Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1948
1949=item %s failed--call queue aborted
1950
3c10abe3
AG
1951(F) An untrapped exception was raised while executing a UNITCHECK,
1952CHECK, INIT, or END subroutine. Processing of the remainder of the
1953queue of such routines has been prematurely ended.
6df41af2 1954
e0e4a6e3 1955=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1956
98d31c73 1957(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1958character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1959in your false range is interpreted as a literal "-". In a C<(?[...])>
1960construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1961the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1962the problem was discovered. See L<perlre>.
73b437c8 1963
1b1ee2ef 1964=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1965
be771a83
GS
1966(P) An error peculiar to VMS. Something untoward happened in a VMS
1967system service or RTL routine; Perl's exit status should provide more
1968details. The filename in "at %s" and the line number in "line %d" tell
1969you which section of the Perl source code is distressed.
a0d0e21e
LW
1970
1971=item fcntl is not implemented
1972
1973(F) Your machine apparently doesn't implement fcntl(). What is this, a
1974PDP-11 or something?
1975
22846ab4
AB
1976=item FETCHSIZE returned a negative value
1977
1978(F) A tied array claimed to have a negative number of elements, which
1979is not possible.
1980
f337b084
TH
1981=item Field too wide in 'u' format in pack
1982
d8b5cc61 1983(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1984which can't encode values above 63. So there is no point in asking for
1985a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1986C<u63> as the format.
f337b084 1987
af8c498a 1988=item Filehandle %s opened only for input
a0d0e21e 1989
6c8d78fb
HS
1990(W io) You tried to write on a read-only filehandle. If you intended
1991it to be a read-write filehandle, you needed to open it with "+<" or
1992"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1993write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1994
af8c498a 1995=item Filehandle %s opened only for output
a0d0e21e 1996
6c8d78fb
HS
1997(W io) You tried to read from a filehandle opened only for writing, If
1998you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1999with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2000read from the file, use "<". See L<perlfunc/open>. Another possibility
2001is that you attempted to open filedescriptor 0 (also known as STDIN) for
2002output (maybe you closed STDIN earlier?).
97828cef
RGS
2003
2004=item Filehandle %s reopened as %s only for input
2005
2006(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2007as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2008previously.
2009
2010=item Filehandle STDIN reopened as %s only for output
2011
2012(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2013as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2014
2015=item Final $ should be \$ or $name
2016
2017(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2018a literal dollar sign, or was meant to introduce a variable name that
2019happens to be missing. So you have to put either the backslash or the
2020name.
a0d0e21e 2021
56e90b21
GS
2022=item flock() on closed filehandle %s
2023
be771a83 2024(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2025some time before now. Check your control flow. flock() operates on
be771a83
GS
2026filehandles. Are you attempting to call flock() on a dirhandle by the
2027same name?
56e90b21 2028
6df41af2
GS
2029=item Format not terminated
2030
2031(F) A format must be terminated by a line with a solitary dot. Perl got
2032to the end of your file without finding such a line.
2033
a0d0e21e
LW
2034=item Format %s redefined
2035
e476b1b5 2036(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2037
2038 {
271595cc 2039 no warnings 'redefine';
a0d0e21e
LW
2040 eval "format NAME =...";
2041 }
2042
a0d0e21e
LW
2043=item Found = in conditional, should be ==
2044
e476b1b5 2045(W syntax) You said
a0d0e21e
LW
2046
2047 if ($foo = 123)
2048
2049when you meant
2050
2051 if ($foo == 123)
2052
2053(or something like that).
2054
6df41af2
GS
2055=item %s found where operator expected
2056
56da5a46
RGS
2057(S syntax) The Perl lexer knows whether to expect a term or an operator.
2058If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2059operator, it gives you this warning. Usually it indicates that an
2060operator or delimiter was omitted, such as a semicolon.
6df41af2 2061
a0d0e21e
LW
2062=item gdbm store returned %d, errno %d, key "%s"
2063
2064(S) A warning from the GDBM_File extension that a store failed.
2065
2066=item gethostent not implemented
2067
2068(F) Your C library apparently doesn't implement gethostent(), probably
2069because if it did, it'd feel morally obligated to return every hostname
2070on the Internet.
2071
69282e91 2072=item get%sname() on closed socket %s
a0d0e21e 2073
be771a83
GS
2074(W closed) You tried to get a socket or peer socket name on a closed
2075socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2076
748a9306
LW
2077=item getpwnam returned invalid UIC %#o for user "%s"
2078
2079(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2080C<getpwnam> operator returned an invalid UIC.
2081
6df41af2
GS
2082=item getsockopt() on closed socket %s
2083
be771a83
GS
2084(W closed) You tried to get a socket option on a closed socket. Did you
2085forget to check the return value of your socket() call? See
6df41af2
GS
2086L<perlfunc/getsockopt>.
2087
0f539b13
BF
2088=item given is experimental
2089
675fa9ff
FC
2090(S experimental::smartmatch) C<given> depends on smartmatch, which
2091is experimental, so its behavior may change or even be removed
2092in any future release of perl. See the explanation under
2093L<perlsyn/Experimental Details on given and when>.
0f539b13 2094
6df41af2
GS
2095=item Global symbol "%s" requires explicit package name
2096
a4edf47d 2097(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2098that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2099declared beforehand using "our", or explicitly qualified to say
2100which package the global variable is in (using "::").
6df41af2 2101
e476b1b5
GS
2102=item glob failed (%s)
2103
5ead438e 2104(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2105for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2106pattern that caused the external program to fail and exit with a
be771a83 2107nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2108resulted in a coredump, this may also mean that your csh (C shell)
2109is broken. If so, you should change all of the csh-related variables
2110in config.sh: If you have tcsh, make the variables refer to it as
2111if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2112all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2113think csh is missing. In either case, after editing config.sh, run
75b44862 2114C<./Configure -S> and rebuild Perl.
e476b1b5 2115
a0d0e21e
LW
2116=item Glob not terminated
2117
2118(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2119a term, so it's looking for the corresponding right angle bracket, and
2120not finding it. Chances are you left some needed parentheses out
2121earlier in the line, and you really meant a "less than".
a0d0e21e 2122
bcd05b94 2123=item gmtime(%f) too large
8b56d6ff 2124
e9200be3 2125(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2126it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2127date. This warning is also triggered with NaN (the special
fc003d4b
MS
2128not-a-number value).
2129
bcd05b94 2130=item gmtime(%f) too small
fc003d4b 2131
e9200be3 2132(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2133it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2134
6df41af2 2135=item Got an error from DosAllocMem
a0d0e21e 2136
6df41af2
GS
2137(P) An error peculiar to OS/2. Most probably you're using an obsolete
2138version of Perl, and this should not happen anyway.
a0d0e21e
LW
2139
2140=item goto must have label
2141
2142(F) Unlike with "next" or "last", you're not allowed to goto an
2143unspecified destination. See L<perlfunc/goto>.
2144
6651ba0b
FC
2145=item Goto undefined subroutine%s
2146
2147(F) You tried to call a subroutine with C<goto &sub> syntax, but
2148the indicated subroutine hasn't been defined, or if it was, it
2149has since been undefined.
2150
6fbc9859 2151=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2152S<<-- HERE> in m/%s/
1f4f6bf1
YO
2153
2154(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2155they must start with a non-digit word character. A common cause of
2156this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2157
5a25739d
FC
2158=item ()-group starts with a count
2159
2160(F) A ()-group started with a count. A count is supposed to follow
2161something: a template character or a ()-group. See L<perlfunc/pack>.
2162
fe13d51d 2163=item %s had compilation errors.
6df41af2
GS
2164
2165(F) The final summary message when a C<perl -c> fails.
2166
a0d0e21e
LW
2167=item Had to create %s unexpectedly
2168
be771a83
GS
2169(S internal) A routine asked for a symbol from a symbol table that ought
2170to have existed already, but for some reason it didn't, and had to be
2171created on an emergency basis to prevent a core dump.
a0d0e21e
LW
2172
2173=item Hash %%s missing the % in argument %d of %s()
2174
be771a83
GS
2175(D deprecated) Really old Perl let you omit the % on hash names in some
2176spots. This is now heavily deprecated.
a0d0e21e 2177
6df41af2
GS
2178=item %s has too many errors
2179
2180(F) The parser has given up trying to parse the program after 10 errors.
2181Further error messages would likely be uninformative.
2182
252aa082
JH
2183=item Hexadecimal number > 0xffffffff non-portable
2184
e476b1b5 2185(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2186(4294967295) and therefore non-portable between systems. See
2187L<perlport> for more on portability concerns.
252aa082 2188
8903cb82
PP
2189=item Identifier too long
2190
2191(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2192about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2193names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2194of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2195
e0e4a6e3
FC
2196=item Ignoring zero length \N{} in character class in regex; marked by
2197S<<-- HERE> in m/%s/
fc8cd66c 2198
b5e3739b
FC
2199(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2200zero-length sequence. When such an escape is used in a character class
2201its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2202been used, and the correct charname handler is in scope.
2203
6df41af2 2204=item Illegal binary digit %s
f675dbe5 2205
6df41af2 2206(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2207
6df41af2 2208=item Illegal binary digit %s ignored
a0d0e21e 2209
be771a83
GS
2210(W digit) You may have tried to use a digit other than 0 or 1 in a
2211binary number. Interpretation of the binary number stopped before the
2212offending digit.
a0d0e21e 2213
6597eb22
FC
2214=item Illegal character after '_' in prototype for %s : %s
2215
e4d150f1
FC
2216(W illegalproto) An illegal character was found in a prototype
2217declaration. The '_' in a prototype must be followed by a ';',
2218indicating the rest of the parameters are optional, or one of '@'
2219or '%', since those two will accept 0 or more final parameters.
6597eb22 2220
78d0fecf 2221=item Illegal character \%o (carriage return)
4fdae800 2222
d5898338 2223(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2224would any other whitespace, which means you should never see this error
2225when Perl was built using standard options. For some reason, your
2226version of Perl appears to have been built without this support. Talk
2227to your Perl administrator.
4fdae800 2228
d37a9538
ST
2229=item Illegal character in prototype for %s : %s
2230
197afce1 2231(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2232Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2233Perhaps you were trying to write a subroutine signature but didn't enable
2234that feature first (C<use feature 'signatures'>), so your signature was
2235instead interpreted as a bad prototype.
d37a9538 2236
904d85c5
RGS
2237=item Illegal declaration of anonymous subroutine
2238
2239(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2240you must always specify a block of code. See L<perlsub>.
904d85c5 2241
8e742a20
MHM
2242=item Illegal declaration of subroutine %s
2243
6903afa2 2244(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2245
a0d0e21e
LW
2246=item Illegal division by zero
2247
be771a83
GS
2248(F) You tried to divide a number by 0. Either something was wrong in
2249your logic, or you need to put a conditional in to guard against
2250meaningless input.
a0d0e21e 2251
6df41af2
GS
2252=item Illegal hexadecimal digit %s ignored
2253
be771a83
GS
2254(W digit) You may have tried to use a character other than 0 - 9 or
2255A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2256number stopped before the illegal character.
6df41af2 2257
a0d0e21e
LW
2258=item Illegal modulus zero
2259
be771a83
GS
2260(F) You tried to divide a number by 0 to get the remainder. Most
2261numbers don't take to this kindly.
a0d0e21e 2262
6df41af2 2263=item Illegal number of bits in vec
399388f4 2264
6df41af2
GS
2265(F) The number of bits in vec() (the third argument) must be a power of
2266two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2267
2268=item Illegal octal digit %s
a0d0e21e 2269
d1be9408 2270(F) You used an 8 or 9 in an octal number.
a0d0e21e 2271
399388f4 2272=item Illegal octal digit %s ignored
748a9306 2273
d1be9408 2274(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2275Interpretation of the octal number stopped before the 8 or 9.
748a9306 2276
e0e4a6e3 2277=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2278
675fa9ff 2279(F) You wrote something like
c608e803
KW
2280
2281 (?+foo)
2282
2283The C<"+"> is valid only when followed by digits, indicating a
2284capturing group. See
2285L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2286
fe13d51d 2287=item Illegal switch in PERL5OPT: -%c
6ff81951 2288
6df41af2 2289(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2290following switches: B<-[CDIMUdmtw]>.
6ff81951 2291
6df41af2 2292=item Ill-formed CRTL environ value "%s"
81e118e0 2293
75b44862 2294(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2295internal environ array, and encountered an element without the C<=>
2296delimiter used to separate keys from values. The element is ignored.
09bef843 2297
6df41af2 2298=item Ill-formed message in prime_env_iter: |%s|
54310121 2299
be771a83
GS
2300(W internal) A warning peculiar to VMS. Perl tried to read a logical
2301name or CLI symbol definition when preparing to iterate over %ENV, and
2302didn't see the expected delimiter between key and value, so the line was
2303ignored.
54310121 2304
6df41af2 2305=item (in cleanup) %s
9607fc9c 2306
be771a83
GS
2307(W misc) This prefix usually indicates that a DESTROY() method raised
2308the indicated exception. Since destructors are usually called by the
2309system at arbitrary points during execution, and often a vast number of
2310times, the warning is issued only once for any number of failures that
2311would otherwise result in the same message being repeated.
6df41af2 2312
be771a83
GS
2313Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2314also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2315
e0e4a6e3
FC
2316=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2317in m/%s/
0d0b4b3b 2318
675fa9ff 2319(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2320expression inside the construct was completely empty, or if there are
2321too many or few operands for the number of operators. Perl is not smart
2322enough to give you a more precise indication as to what is wrong.
2323
6fbc9859
MH
2324=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2325parent '%s'
2c7d6b9c
RGS
2326
2327(F) The method resolution order (MRO) of the given class is not
2328C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2329documentation in L<mro> for more information.
2330
979699d9
JH
2331=item In EBCDIC the v-string components cannot exceed 2147483647
2332
2333(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2334Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2335encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2336
6a2ed79a 2337=item Infinite recursion in regex
1a147d38
YO
2338
2339(F) You used a pattern that references itself without consuming any input
6903afa2 2340text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2341either consume text or fail.
2342
6dbe9451
NC
2343=item Initialization of state variables in list context currently forbidden
2344
6903afa2
FC
2345(F) Currently the implementation of "state" only permits the
2346initialization of scalar variables in scalar context. Re-write
2347C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2348context. Constructions such as C<state (@a) = foo()> will be
2349supported in a future perl release.
6dbe9451 2350
2186f873
FC
2351=item %%s[%s] in scalar context better written as $%s[%s]
2352
2353(W syntax) In scalar context, you've used an array index/value slice
2354(indicated by %) to select a single element of an array. Generally
2355it's better to ask for a scalar value (indicated by $). The difference
2356is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2357returns and when evaluating its argument, while C<%foo[&bar]> provides
2358a list context to its subscript, which can do weird things if you're
2359expecting only one subscript. When called in list context, it also
2360returns the index (what C<&bar> returns) in addition to the value.
2361
2362=item %%s{%s} in scalar context better written as $%s{%s}
2363
2364(W syntax) In scalar context, you've used a hash key/value slice
2365(indicated by %) to select a single element of a hash. Generally it's
2366better to ask for a scalar value (indicated by $). The difference
2367is that C<$foo{&bar}> always behaves like a scalar, both in the value
2368it returns and when evaluating its argument, while C<@foo{&bar}> and
2369provides a list context to its subscript, which can do weird things
2370if you're expecting only one subscript. When called in list context,
2371it also returns the key in addition to the value.
2372
a0d0e21e
LW
2373=item Insecure dependency in %s
2374
8b1a09fc 2375(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2376The tainting mechanism is turned on when you're running setuid or
2377setgid, or when you specify B<-T> to turn it on explicitly. The
2378tainting mechanism labels all data that's derived directly or indirectly
2379from the user, who is considered to be unworthy of your trust. If any
2380such data is used in a "dangerous" operation, you get this error. See
2381L<perlsec> for more information.
a0d0e21e
LW
2382
2383=item Insecure directory in %s
2384
be771a83
GS
2385(F) You can't use system(), exec(), or a piped open in a setuid or
2386setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2387the world. Also, the PATH must not contain any relative directory.
2388See L<perlsec>.
a0d0e21e 2389
62f468fc 2390=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2391
2392(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2393setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2394C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2395supplied (or potentially supplied) by the user. The script must set
2396the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2397
0e9be77f
DM
2398=item Insecure user-defined property %s
2399
2400(F) Perl detected tainted data when trying to compile a regular
2401expression that contains a call to a user-defined character property
2402function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2403See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2404
e0e4a6e3
FC
2405=item In '(?...)', splitting the initial '(?' is deprecated in regex;
2406marked by S<<-- HERE> in m/%s/
675fa9ff
FC
2407
2408(D regexp, deprecated) The two-character sequence C<"(?"> in
2409this context in a regular expression pattern should be an
2410indivisible token, with nothing intervening between the C<"(">
2411and the C<"?">, but you separated them. Due to an accident of
2412implementation, this prohibition was not enforced, but we do
2413plan to forbid it in a future Perl version. This message
2414serves as giving you fair warning of this pending change.
2415
b9ef414d
FC
2416=item Integer overflow in format string for %s
2417
2418(F) The indexes and widths specified in the format string of C<printf()>
2419or C<sprintf()> are too large. The numbers must not overflow the size of
2420integers for your architecture.
2421
a7ae9550
GS
2422=item Integer overflow in %s number
2423
35928bc5 2424(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2425either as a literal or as an argument to hex() or oct() is too big for
2426your architecture, and has been converted to a floating point number.
2427On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2428representable without overflow is 0xFFFFFFFF, 037777777777, or
24290b11111111111111111111111111111111 respectively. Note that Perl
2430transparently promotes all numbers to a floating point representation
2431internally--subject to loss of precision errors in subsequent
2432operations.
bbce6d69 2433
fc89ca81
FC
2434=item Integer overflow in srand
2435
2436(S overflow) The number you have passed to srand is too big to fit
2437in your architecture's integer representation. The number has been
2438replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2439architectures). This means you may be getting less randomness than
2440you expect, because different random seeds above the maximum will
2441return the same sequence of random numbers.
2442
46314c13
JP
2443=item Integer overflow in version
2444
18da5252
FC
2445=item Integer overflow in version %d
2446
784d71ed
FC
2447(W overflow) Some portion of a version initialization is too large for
2448the size of integers for your architecture. This is not a warning
f084e84f 2449because there is no rational reason for a version to try and use an
784d71ed
FC
2450element larger than typically 2**32. This is usually caused by trying
2451to use some odd mathematical operation as a version, like 100/9.
46314c13 2452
e0e4a6e3 2453=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2454
2455(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2456The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2457discovered.
2458
748a9306
LW
2459=item Internal inconsistency in tracking vforks
2460
be771a83
GS
2461(S) A warning peculiar to VMS. Perl keeps track of the number of times
2462you've called C<fork> and C<exec>, to determine whether the current call
2463to C<exec> should affect the current script or a subprocess (see
2464L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2465Perl is making a guess and treating this C<exec> as a request to
2466terminate the Perl script and execute the specified command.
748a9306 2467
870978ae
FC
2468=item internal %<num>p might conflict with future printf extensions
2469
2470(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2471formatting follows a slightly different set of rules when called from
2472C or XS code. Specifically, formats consisting of digits followed
2473by "p" (e.g., "%7p") are reserved for future use. If you see this
2474message, then an XS module tried to call that routine with one such
2475reserved format.
2476
e0e4a6e3 2477=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2478
fa816bf3 2479(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2480S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2481discovered.
a0d0e21e 2482
6df41af2
GS
2483=item %s (...) interpreted as function
2484
75b44862 2485(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2486followed by parentheses turns into a function, with all the list
64977eb6 2487operators arguments found inside the parentheses. See
13a2d996 2488L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2489
09bef843
SB
2490=item Invalid %s attribute: %s
2491
a4a4c9e2 2492(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2493by Perl or by a user-supplied handler. See L<attributes>.
2494
2495=item Invalid %s attributes: %s
2496
a4a4c9e2 2497(F) The indicated attributes for a subroutine or variable were not
be771a83 2498recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2499
e0e4a6e3
FC
2500=item Invalid character in charnames alias definition; marked by
2501S<<-- HERE> in '%s
225fb84f
KW
2502
2503(F) You tried to create a custom alias for a character name, with
2504the C<:alias> option to C<use charnames> and the specified character in
2505the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2506
c8028aa6
TC
2507=item Invalid \0 character in %s for %s: %s\0%s
2508
fa3234e3
FC
2509(W syscalls) Embedded \0 characters in pathnames or other system call
2510arguments produce a warning as of 5.20. The parts after the \0 were
2511formerly ignored by system calls.
c8028aa6 2512
e0e4a6e3 2513=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2514
2515(F) Only certain characters are valid for character names. The
2516indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2517
c635e13b
PP
2518=item Invalid conversion in %s: "%s"
2519
be771a83
GS
2520(W printf) Perl does not understand the given format conversion. See
2521L<perlfunc/sprintf>.
c635e13b 2522
e0e4a6e3
FC
2523=item Invalid escape in the specified encoding in regex; marked by
2524S<<-- HERE> in m/%s/
9e08bc66 2525
98d31c73 2526(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2527didn't correspond to a single character through the conversion
2528from the encoding specified by the encoding pragma.
98d31c73
FC
2529The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2530instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2531The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2532escape was discovered.
2533
8149aa9f
FC
2534=item Invalid hexadecimal number in \N{U+...}
2535
e0e4a6e3
FC
2536=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2537S<<-- HERE> in m/%s/
aec0ef10 2538
8149aa9f 2539(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2540number. Either it is empty, or you tried to use a character other than
25410 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2542
6651ba0b
FC
2543=item Invalid module name %s with -%c option: contains single ':'
2544
2545(F) The module argument to perl's B<-m> and B<-M> command-line options
2546cannot contain single colons in the module name, but only in the
2547arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2548B<-MFoo:Bar=baz> is not.
2549
2c7d6b9c
RGS
2550=item Invalid mro name: '%s'
2551
162a3e34
FC
2552(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2553where C<foo> is not a valid method resolution order (MRO). Currently,
2554the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2555a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2556
40e4140b
FC
2557=item Invalid negative number (%s) in chr
2558
2559(W utf8) You passed a negative number to C<chr>. Negative numbers are
2560not valid characters numbers, so it return the Unicode replacement
2561character (U+FFFD).
2562
6651ba0b
FC
2563=item invalid option -D%c, use -D'' to see choices
2564
8ff21bfe
FC
2565(S debugging) Perl was called with invalid debugger flags. Call perl
2566with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2567See also L<perlrun/-Dletters>.
6651ba0b 2568
e0e4a6e3 2569=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2570
2571(F) The range specified in a character class had a minimum character
7253e4e3
RK
2572greater than the maximum character. One possibility is that you forgot the
2573C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2574up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2575problem was discovered. See L<perlre>.
6df41af2 2576
d1573ac7 2577=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2578
2579(F) The range specified in the tr/// or y/// operator had a minimum
2580character greater than the maximum character. See L<perlop>.
2581
09bef843
SB
2582=item Invalid separator character %s in attribute list
2583
0120eecf 2584(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2585elements of an attribute list. If the previous attribute had a
2586parenthesised parameter list, perhaps that list was terminated too soon.
2587See L<attributes>.
09bef843 2588
b4581f09
JH
2589=item Invalid separator character %s in PerlIO layer specification %s
2590
2bfc5f71
FC
2591(W layer) When pushing layers onto the Perl I/O system, something other
2592than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2593If the previous attribute had a parenthesised parameter list, perhaps that
2594list was terminated too soon.
2595
2c86d456
DG
2596=item Invalid strict version format (%s)
2597
fa816bf3 2598(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2599A "strict" version number is a positive decimal number (integer or
2600decimal-fraction) without exponentiation or else a dotted-decimal
2601v-string with a leading 'v' character and at least three components.
a6485a24 2602The parenthesized text indicates which criteria were not met.
2c86d456
DG
2603See the L<version> module for more details on allowed version formats.
2604
49704364 2605=item Invalid type '%s' in %s
96e4d5b1 2606
49704364
LW
2607(F) The given character is not a valid pack or unpack type.
2608See L<perlfunc/pack>.
6728c851 2609
49704364 2610(W) The given character is not a valid pack or unpack type but used to be
75b44862 2611silently ignored.
96e4d5b1 2612
2c86d456
DG
2613=item Invalid version format (%s)
2614
fa816bf3 2615(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2616A "lax" version number is a positive decimal number (integer or
2617decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2618v-string. If the v-string has fewer than three components, it
2619must have a leading 'v' character. Otherwise, the leading 'v' is
2620optional. Both decimal and dotted-decimal versions may have a
2621trailing "alpha" component separated by an underscore character
2622after a fractional or dotted-decimal component. The parenthesized
2623text indicates which criteria were not met. See the L<version> module
2624for more details on allowed version formats.
46314c13 2625
798ae1b7
DG
2626=item Invalid version object
2627
fa816bf3
FC
2628(F) The internal structure of the version object was invalid.
2629Perhaps the internals were modified directly in some way or
2630an arbitrary reference was blessed into the "version" class.
798ae1b7 2631
e0e4a6e3
FC
2632=item In '(*VERB...)', splitting the initial '(*' is deprecated in regex;
2633marked by S<<-- HERE> in m/%s/
675fa9ff
FC
2634
2635(D regexp, deprecated) The two-character sequence C<"(*"> in
2636this context in a regular expression pattern should be an
2637indivisible token, with nothing intervening between the C<"(">
f26c79ba 2638and the C<"*">, but you separated them. Due to an accident of
675fa9ff
FC
2639implementation, this prohibition was not enforced, but we do
2640plan to forbid it in a future Perl version. This message
2641serves as giving you fair warning of this pending change.
2642
a0d0e21e
LW
2643=item ioctl is not implemented
2644
2645(F) Your machine apparently doesn't implement ioctl(), which is pretty
2646strange for a machine that supports C.
2647
c289d2f7
JH
2648=item ioctl() on unopened %s
2649
2650(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2651Check your control flow and number of arguments.
c289d2f7 2652
fe13d51d 2653=item IO layers (like '%s') unavailable
363c40c4
SB
2654
2655(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2656you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2657with 'useperlio'.
2658
80cbd5ad
JH
2659=item IO::Socket::atmark not implemented on this architecture
2660
2661(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2662neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2663
4f650b80 2664=item $* is no longer supported
b4581f09 2665
4f650b80 2666(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2667perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2668previous versions of perl the use of C<$*> enabled or disabled multi-line
2669matching within a string.
4fd19576
B
2670
2671Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2672modifiers. You can enable C</m> for a lexical scope (even a whole file)
2673with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2674then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2675
8ae1fe26
RGS
2676=item $# is no longer supported
2677
a58ac25e 2678(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2679perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2680should use the printf/sprintf functions instead.
8ae1fe26 2681
ccf3535a 2682=item '%s' is not a code reference
6ad11d81 2683
6903afa2
FC
2684(W overload) The second (fourth, sixth, ...) argument of
2685overload::constant needs to be a code reference. Either
2686an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2687
ccf3535a 2688=item '%s' is not an overloadable type
6ad11d81 2689
04a80ee0
RGS
2690(W overload) You tried to overload a constant type the overload package is
2691unaware of.
6ad11d81 2692
5a25739d
FC
2693=item -i used with no filenames on the command line, reading from STDIN
2694
2695(S inplace) The C<-i> option was passed on the command line, indicating
2696that the script is intended to edit files in place, but no files were
2697given. This is usually a mistake, since editing STDIN in place doesn't
2698make sense, and can be confusing because it can make perl look like
2699it is hanging when it is really just trying to read from STDIN. You
2700should either pass a filename to edit, or remove C<-i> from the command
2701line. See L<perlrun> for more details.
2702
aec0ef10 2703=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2704
2705(P) The regular expression parser is confused.
2706
0953b66b
FC
2707=item keys on reference is experimental
2708
0773cb3e
FC
2709(S experimental::autoderef) C<keys> with a scalar argument is experimental
2710and may change or be removed in a future Perl version. If you want to
2711take the risk of using this feature, simply disable this warning:
0953b66b 2712
d401967c 2713 no warnings "experimental::autoderef";
0953b66b 2714
a0d0e21e
LW
2715=item Label not found for "last %s"
2716
be771a83
GS
2717(F) You named a loop to break out of, but you're not currently in a loop
2718of that name, not even if you count where you were called from. See
2719L<perlfunc/last>.
a0d0e21e
LW
2720
2721=item Label not found for "next %s"
2722
2723(F) You named a loop to continue, but you're not currently in a loop of
2724that name, not even if you count where you were called from. See
2725L<perlfunc/last>.
2726
2727=item Label not found for "redo %s"
2728
2729(F) You named a loop to restart, but you're not currently in a loop of
2730that name, not even if you count where you were called from. See
2731L<perlfunc/last>.
2732
85ab1d1d 2733=item leaving effective %s failed
5ff3f7a4 2734
85ab1d1d 2735(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2736effective uids or gids failed.
2737
49704364
LW
2738=item length/code after end of string in unpack
2739
d7f8936a 2740(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2741length/code combination tried to obtain more data. This results in
2742an undefined value for the length. See L<perlfunc/pack>.
49704364 2743
25e26107 2744=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2745
0d46a4e7
FC
2746(W syntax) You used length() on either an array or a hash when you
2747probably wanted a count of the items.
e508c8a4
MH
2748
2749Array size can be obtained by doing:
2750
2751 scalar(@array);
2752
2753The number of items in a hash can be obtained by doing:
2754
2755 scalar(keys %hash);
2756
f0e67a1d
Z
2757=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2758
d4fe7078
RS
2759(F) An extension is attempting to insert text into the current parse
2760(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2761couldn't be part of the current input. This is an inherent pitfall
2762of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2763it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2764
2765=item Lexing code internal error (%s)
2766
2767(F) Lexing code supplied by an extension violated the lexer's API in a
2768detectable way.
2769
69282e91 2770=item listen() on closed socket %s
a0d0e21e 2771
be771a83
GS
2772(W closed) You tried to do a listen on a closed socket. Did you forget
2773to check the return value of your socket() call? See
2774L<perlfunc/listen>.
a0d0e21e 2775
6651ba0b
FC
2776=item List form of piped open not implemented
2777
2778(F) On some platforms, notably Windows, the three-or-more-arguments
2779form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2780Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2781
bcd05b94 2782=item localtime(%f) too large
8b56d6ff 2783
e9200be3 2784(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2785than it can reliably handle and C<localtime> probably returned the
6903afa2 2786wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2787not-a-number value).
2788
bcd05b94 2789=item localtime(%f) too small
fc003d4b 2790
e9200be3 2791(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2792than it can reliably handle and C<localtime> probably returned the
e7a1a147 2793wrong date.
8b56d6ff 2794
58e23c8d 2795=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2796
2797(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2798handle. This restriction may be eased in a future release.
2e50fd82 2799
b88df990
NC
2800=item Lost precision when %s %f by 1
2801
e63e8a91
FC
2802(W imprecision) The value you attempted to increment or decrement by one
2803is too large for the underlying floating point representation to store
2804accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2805warning because it has already switched from integers to floating point
2806when values are too large for integers, and now even floating point is
2807insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2808
93fad930 2809=item lstat() on filehandle%s
2f7da168
RK
2810
2811(W io) You tried to do an lstat on a filehandle. What did you mean
2812by that? lstat() makes sense only on filenames. (Perl did a fstat()
2813instead on the filehandle.)
2814
345d70e3 2815=item lvalue attribute %s already-defined subroutine
bb3abb05 2816
345d70e3
FC
2817(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2818attribute on or off on a Perl subroutine that is already defined
2819does not always work properly. It may or may not do what you
2820want, depending on what code is inside the subroutine, with exact
2821details subject to change between Perl versions. Only do this
2822if you really know what you are doing.
bb3abb05 2823
885ef6f5
GG
2824=item lvalue attribute ignored after the subroutine has been defined
2825
345d70e3
FC
2826(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2827subroutine an lvalue subroutine after it has been defined is
2828not permitted. To make the subroutine an lvalue subroutine,
2829add the lvalue attribute to the definition, or put the C<sub
2830foo :lvalue;> declaration before the definition.
2831
2832See also L<attributes.pm|attributes>.
885ef6f5 2833
6f1b3ab0
FC
2834=item Magical list constants are not supported
2835
2836(F) You assigned a magical array to a stash element, and then tried
2837to use the subroutine from the same slot. You are asking Perl to do
2838something it cannot do, details subject to change between Perl versions.
2839
2db62bbc 2840=item Malformed integer in [] in pack
49704364 2841
2db62bbc 2842(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2843are permitted. See L<perlfunc/pack>.
2844
2845=item Malformed integer in [] in unpack
2846
2db62bbc 2847(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2848are permitted. See L<perlfunc/pack>.
2849
6df41af2
GS
2850=item Malformed PERLLIB_PREFIX
2851
2852(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2853
2854 prefix1;prefix2
2855
2856or
6df41af2
GS
2857 prefix1 prefix2
2858
be771a83
GS
2859with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2860a builtin library search path, prefix2 is substituted. The error may
2861appear if components are not found, or are too long. See
fecfaeb8 2862"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2863
2f758a16
ST
2864=item Malformed prototype for %s: %s
2865
d37a9538
ST
2866(F) You tried to use a function with a malformed prototype. The
2867syntax of function prototypes is given a brief compile-time check for
2868obvious errors like invalid characters. A more rigorous check is run
2869when the function is called.
30d9c59b
Z
2870Perhaps the function's author was trying to write a subroutine signature
2871but didn't enable that feature first (C<use feature 'signatures'>),
2872so the signature was instead interpreted as a bad prototype.
2f758a16 2873
ba210ebe
JH
2874=item Malformed UTF-8 character (%s)
2875
4d6f11e5 2876(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2877encoding rules, even though it had the UTF8 flag on.
ba210ebe 2878
2575c402
JW
2879One possible cause is that you set the UTF8 flag yourself for data that
2880you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28818-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2882
2883If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2884sequences are handled gracefully, but if you use C<:utf8>, the flag is
2885set without validating the data, possibly resulting in this error
2886message.
2887
2888See also L<Encode/"Handling Malformed Data">.
901b21bf 2889
107160e2
KW
2890=item Malformed UTF-8 character immediately after '%s'
2891
2892(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2893encoding rules. The message prints out the properly encoded characters
2894just before the first bad one. If C<utf8> warnings are enabled, a
2895warning is generated that gives more details about the type of
2896malformation.
2897
bde9e88d 2898=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2899
2900(F) The charnames handler returned malformed UTF-8.
2901
4a5d3a93
FC
2902=item Malformed UTF-8 string in '%c' format in unpack
2903
2904(F) You tried to unpack something that didn't comply with UTF-8 encoding
2905rules and perl was unable to guess how to make more progress.
2906
f337b084
TH
2907=item Malformed UTF-8 string in pack
2908
2909(F) You tried to pack something that didn't comply with UTF-8 encoding
2910rules and perl was unable to guess how to make more progress.
2911
2912=item Malformed UTF-8 string in unpack
2913
2914(F) You tried to unpack something that didn't comply with UTF-8 encoding
2915rules and perl was unable to guess how to make more progress.
2916
4a5d3a93 2917=item Malformed UTF-16 surrogate
f337b084 2918
4a5d3a93
FC
2919(F) Perl thought it was reading UTF-16 encoded character data but while
2920doing it Perl met a malformed Unicode surrogate.
2921
30d9c59b
Z
2922=item Mandatory parameter follows optional parameter
2923
2924(F) In a subroutine signature, you wrote something like "$a = undef,
2925$b", making an earlier parameter optional and a later one mandatory.
2926Parameters are filled from left to right, so it's impossible for the
2927caller to omit an earlier one and pass a later one. If you want to act
2928as if the parameters are filled from right to left, declare the rightmost
2929optional and then shuffle the parameters around in the subroutine's body.
2930
2d88a86a
KW
2931=item Matched non-Unicode code point 0x%X against Unicode property; may
2932not be portable
2933
2934(S non_unicode) Perl allows strings to contain a superset of
2935Unicode code points; each code point may be as large as what is storable
2936in an unsigned integer on your system, but these may not be accepted by
2937other languages/systems. This message occurs when you matched a string
2938containing such a code point against a regular expression pattern, and
2939the code point was matched against a Unicode property, C<\p{...}> or
2940C<\P{...}>. Unicode properties are only defined on Unicode code points,
2941so the result of this match is undefined by Unicode, but Perl (starting
2942in v5.20) treats non-Unicode code points as if they were typical
2943unassigned Unicode ones, and matched this one accordingly. Whether a
2944given property matches these code points or not is specified in
2945L<perluniprops/Properties accessible through \p{} and \P{}>.
2946
2947This message is suppressed (unless it has been made fatal) if it is
2948immaterial to the results of the match if the code point is Unicode or
2949not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2950the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2951Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2952every code point except these 22.)
2953
2954Getting this message indicates that the outcome of the match arguably
2955should have been the opposite of what actually happened. If you think
2956that is the case, you may wish to make the C<non_unicode> warnings
2957category fatal; if you agree with Perl's decision, you may wish to turn
2958off this category.
2959
2960See L<perlunicode/Beyond Unicode code points> for more information.
2961
e0e4a6e3
FC
2962=item %s matches null string many times in regex; marked by S<<-- HERE> in
2963m/%s/
4a5d3a93
FC
2964
2965(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2966regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2967shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2968See L<perlre>.
f337b084 2969
de42a5a9 2970=item Maximal count of pending signals (%u) exceeded
2563cec5 2971
6903afa2 2972(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2973usually indicates that your operating system tried to deliver signals
2974too fast (with a very high priority), starving the perl process from
2975resources it would need to reach a point where it can process signals
6903afa2 2976safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2977
25f58aea
PN
2978=item "%s" may clash with future reserved word
2979
2980(W) This warning may be due to running a perl5 script through a perl4
2981interpreter, especially if the word that is being warned about is
2982"use" or "my".
2983
0d2487cd 2984=item '%' may not be used in pack
6df41af2
GS
2985
2986(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2987checksumming process loses information, and you can't go the other way.
2988See L<perlfunc/unpack>.
6df41af2 2989
a0d0e21e
LW
2990=item Method for operation %s not found in package %s during blessing
2991
2992(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2993doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2994
3cdd684c
TP
2995=item Method %s not permitted
2996
2997See Server error.
2998
a0d0e21e
LW
2999=item Might be a runaway multi-line %s string starting on line %d
3000
3001(S) An advisory indicating that the previous error may have been caused
3002by a missing delimiter on a string or pattern, because it eventually
3003ended earlier on the current line.
3004
3005=item Misplaced _ in number
3006
d4ced10d
JH
3007(W syntax) An underscore (underbar) in a numeric constant did not
3008separate two digits.
a0d0e21e 3009
7baa4690
HS
3010=item Missing argument in %s
3011
3012(W uninitialized) A printf-type format required more arguments than were
3013supplied.
3014
9e81e6a1
RGS
3015=item Missing argument to -%c
3016
3017(F) The argument to the indicated command line switch must follow
3018immediately after the switch, without intervening spaces.
3019
ff3f963a 3020=item Missing braces on \N{}
423cee85 3021
e0e4a6e3 3022=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3023
4a2d328f 3024(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3025double-quotish context. This can also happen when there is a space
3026(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3027This modifier does not change the requirement that the brace immediately
3028follow the C<\N>.
423cee85 3029
f0a2b745
KW
3030=item Missing braces on \o{}
3031
3032(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3033
a0d0e21e
LW
3034=item Missing comma after first argument to %s function
3035
3036(F) While certain functions allow you to specify a filehandle or an
3037"indirect object" before the argument list, this ain't one of them.
3038
06eaf0bc
GS
3039=item Missing command in piped open
3040
be771a83
GS
3041(W pipe) You used the C<open(FH, "| command")> or
3042C<open(FH, "command |")> construction, but the command was missing or
3043blank.
06eaf0bc 3044
961ce445
RGS
3045=item Missing control char name in \c
3046
3047(F) A double-quoted string ended with "\c", without the required control
3048character name.
3049
591f5ca2
FC
3050=item Missing ']' in prototype for %s : %s
3051
bfe11873 3052(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3053
8767b1ab 3054=item Missing name in "%s sub"
6df41af2 3055
87444db5 3056(F) The syntax for lexically scoped subroutines requires that
be771a83 3057they have a name with which they can be found.
6df41af2
GS
3058
3059=item Missing $ on loop variable
3060
be771a83
GS
3061(F) Apparently you've been programming in B<csh> too much. Variables
3062are always mentioned with the $ in Perl, unlike in the shells, where it
3063can vary from one line to the next.
6df41af2 3064
cc507455 3065=item (Missing operator before %s?)
748a9306 3066
56da5a46
RGS
3067(S syntax) This is an educated guess made in conjunction with the message
3068"%s found where operator expected". Often the missing operator is a comma.
748a9306 3069
e0e4a6e3 3070=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3071
ff3f963a
KW
3072(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3073
4a68bf9d 3074=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3075
d32207c9
FC
3076(F) C<\N> has two meanings.
3077
3078The traditional one has it followed by a name enclosed in braces,
3079meaning the character (or sequence of characters) given by that
fa816bf3 3080name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3081double-quoted strings and regular expression patterns. In patterns,
3082it doesn't have the meaning an unescaped C<*> does.
3083
3084Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3085in patterns, namely to match a non-newline character. (This is short
3086for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3087
3088This can lead to some ambiguities. When C<\N> is not followed immediately
3089by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3090form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3091means to match the given quantity of non-newlines (in these examples,
30923; and 5 or more, respectively). In all other case, where there is a
3093C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3094
3095However, if there is no matching C<}>, Perl doesn't know if it was
3096mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3097If you meant the former, add the right brace; if you meant the latter,
3098escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3099
d98d5fff 3100=item Missing right curly or square bracket
a0d0e21e 3101
be771a83
GS
3102(F) The lexer counted more opening curly or square brackets than closing
3103ones. As a general rule, you'll find it's missing near the place you
3104were last editing.
a0d0e21e 3105
6df41af2
GS
3106=item (Missing semicolon on previous line?)
3107
56da5a46
RGS
3108(S syntax) This is an educated guess made in conjunction with the message
3109"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3110the previous line just because you saw this message.
3111
a0d0e21e
LW
3112=item Modification of a read-only value attempted
3113
3114(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3115constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3116catches that. But an easy way to do the same thing is:
3117
3118 sub mod { $_[0] = 1 }
3119 mod(2);
3120
3121Another way is to assign to a substr() that's off the end of the string.
3122
c5674021
PDF
3123Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3124is aliased to a constant in the look I<LIST>:
3125
b7e4ecc1
FC
3126 $x = 1;
3127 foreach my $n ($x, 2) {
3128 $n *= 2; # modifies the $x, but fails on attempt to
3129 } # modify the 2
c5674021 3130
7a4340ed 3131=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3132
3133(F) You tried to make an array value spring into existence, and the
3134subscript was probably negative, even counting from end of the array
3135backwards.
3136
7a4340ed 3137=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3138
be771a83
GS
3139(P) You tried to make a hash value spring into existence, and it
3140couldn't be created for some peculiar reason.
a0d0e21e
LW
3141
3142=item Module name must be constant
3143
3144(F) Only a bare module name is allowed as the first argument to a "use".
3145
be98fb35 3146=item Module name required with -%c option
6df41af2 3147
be98fb35
GS
3148(F) The C<-M> or C<-m> options say that Perl should load some module, but
3149you omitted the name of the module. Consult L<perlrun> for full details
3150about C<-M> and C<-m>.
6df41af2 3151
fe13d51d 3152=item More than one argument to '%s' open
ed9aa3b7 3153
6903afa2 3154(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3155can happen if you are trying to open a pipe to a command that takes a
3156list of arguments, but have forgotten to specify a piped open mode.
3157See L<perlfunc/open> for details.
3158
85396b18
FC
3159=item mprotect for COW string %p %u failed with %d
3160
3161(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3162L<perlguts/"Copy on Write">), but a shared string buffer
3163could not be made read-only.
3164
92951bce
FC
3165=item mprotect for %p %u failed with %d
3166
85396b18
FC
3167(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3168but an op tree could not be made read-only.
3169
3170=item mprotect RW for COW string %p %u failed with %d
3171
3172(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3173L<perlguts/"Copy on Write">), but a read-only shared string
3174buffer could not be made mutable.
3175
92951bce
FC
3176=item mprotect RW for %p %u failed with %d
3177
3178(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3179L<perlhacktips>), but a read-only op tree could not be made
3180mutable before freeing the ops.
92951bce 3181
a0d0e21e
LW
3182=item msg%s not implemented
3183
3184(F) You don't have System V message IPC on your system.
3185
3186=item Multidimensional syntax %s not supported
3187
75b44862
GS
3188(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3189They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3190
49704364 3191=item '/' must follow a numeric type in unpack
6df41af2 3192
49704364
LW
3193(F) You had an unpack template that contained a '/', but this did not
3194follow some unpack specification producing a numeric value.
3195See L<perlfunc/pack>.
6df41af2
GS
3196
3197=item "my sub" not yet implemented
3198
be771a83
GS
3199(F) Lexically scoped subroutines are not yet implemented. Don't try
3200that yet.
6df41af2 3201
5a25739d
FC
3202=item "my %s" used in sort comparison
3203
3204(W syntax) The package variables $a and $b are used for sort comparisons.
3205You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3206sort comparison block, and the variable had earlier been declared as a
3207lexical variable. Either qualify the sort variable with the package
3208name, or rename the lexical variable.
3209
fd1b7234 3210=item "my" variable %s can't be in a package
6df41af2 3211
be771a83
GS
3212(F) Lexically scoped variables aren't in a package, so it doesn't make
3213sense to try to declare one with a package qualifier on the front. Use
3214local() if you want to localize a package variable.
09bef843 3215
8149aa9f
FC
3216=item Name "%s::%s" used only once: possible typo
3217
c59aba6c
FC
3218(W once) Typographical errors often show up as unique variable
3219names. If you had a good reason for having a unique name, then
3220just mention it again somehow to suppress the message. The C<our>
3221declaration is provided for this purpose.
3222
3223NOTE: This warning detects symbols that have been used only once
3224so $c, @c, %c, *c, &c, sub c{}, c(), and c (the filehandle or
3225format) are considered the same; if a program uses $c only once
3226but also uses any of the others it will not trigger this warning.
3227Symbols beginning with an underscore and symbols using special
3228identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3229
e0e4a6e3 3230=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3231
3232(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3233exactly 3 digits long. This helps catch some ambiguities. If your
3234constant is too short, add leading zeros, like
3235
3236 (?[ [ \078 ] ]) # Syntax error!
3237 (?[ [ \0078 ] ]) # Works
3238 (?[ [ \007 8 ] ]) # Clearer
3239
3240The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3241need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3242two separate things, you need to separate them:
0d0b4b3b
KW
3243
3244 (?[ [ \7776 ] ]) # Syntax error!
3245 (?[ [ \o{7776} ] ]) # One meaning
3246 (?[ [ \777 6 ] ]) # Another meaning
3247 (?[ [ \777 \006 ] ]) # Still another
3248
49704364
LW
3249=item Negative '/' count in unpack
3250
3251(F) The length count obtained from a length/code unpack operation was
3252negative. See L<perlfunc/pack>.
3253
a0d0e21e
LW
3254=item Negative length
3255
be771a83
GS
3256(F) You tried to do a read/write/send/recv operation with a buffer
3257length that is less than 0. This is difficult to imagine.
a0d0e21e 3258
ed9aa3b7
SG
3259=item Negative offset to vec in lvalue context
3260
3261(F) When C<vec> is called in an lvalue context, the second argument must be
3262greater than or equal to zero.
3263
e0e4a6e3 3264=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3265
6903afa2 3266(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3267So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3268whereabouts in the regular expression the problem was discovered.
a0d0e21e 3269
7253e4e3 3270Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3271C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3272
6df41af2 3273=item %s never introduced
a0d0e21e 3274
be771a83
GS
3275(S internal) The symbol in question was declared but somehow went out of
3276scope before it could possibly have been used.
a0d0e21e 3277
2c7d6b9c
RGS
3278=item next::method/next::can/maybe::next::method cannot find enclosing method
3279
3280(F) C<next::method> needs to be called within the context of a
3281real method in a real package, and it could not find such a context.
3282See L<mro>.
3283
5a25739d 3284=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3285marked by S<<-- HERE> in m/%s/
5a25739d 3286
32a77fbe
FC
3287(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3288bracketed character class, for the same reason that C<.> in a character
3289class loses its specialness: it matches almost everything, which is
3290probably not what you want.
5a25739d 3291
0b4ce96d 3292=item \N{} in character class restricted to one character in regex; marked
e0e4a6e3 3293by S<<-- HERE> in m/%s/
0b4ce96d
FC
3294
3295(F) Named Unicode character escapes C<(\N{...})> may return a
3296multi-character sequence. Such an escape may not be used in
3297a character class, because character classes always match one
3298character of input. Check that the correct escape has been used,
e0e4a6e3 3299and the correct charname handler is in scope. The S<<-- HERE> shows
0b4ce96d
FC
3300whereabouts in the regular expression the problem was discovered.
3301
e0e4a6e3
FC
3302=item \N{NAME} must be resolved by the lexer in regex; marked by
3303S<<-- HERE> in m/%s/
5a25739d
FC
3304
3305(F) When compiling a regex pattern, an unresolved named character or
3306sequence was encountered. This can happen in any of several ways that
3307bypass the lexer, such as using single-quotish context, or an extra
3308backslash in double-quotish:
3309