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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 assertion botched: %s
197
21b5e840 198(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 199
0eacef8e 200=item Assertion %s failed: file "%s", line %d
a0d0e21e 201
21b5e840 202(X) A general assertion failed. The file in question must be examined.
a0d0e21e 203
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204=item Assigned value is not a reference
205
206(F) You tried to assign something that was not a reference to an lvalue
207reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
208C<\$x = \$y>.
209
210=item Assigned value is not %s reference
211
212(F) You tried to assign a reference to an lvalue reference, but the two
213references were not of the same type. You cannot alias a scalar to an
214array, or an array to a hash; the two types must match.
215
216 \$x = \@y; # error
217 \@x = \%y; # error
218 $y = [];
219 \$x = $y; # error; did you mean \$y?
220
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221=item Assigning non-zero to $[ is no longer possible
222
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223(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
224the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 225
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226=item Assignment to both a list and a scalar
227
228(F) If you assign to a conditional operator, the 2nd and 3rd arguments
229must either both be scalars or both be lists. Otherwise Perl won't
230know which context to supply to the right side.
231
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232=item <> at require-statement should be quotes
233
234(F) You wrote C<< require <file> >> when you should have written
235C<require 'file'>.
236
2393f1b9 237=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 238
49293501 239(F) The failing code has attempted to get or set a key which is not in
2393f1b9 240the current set of allowed keys of a restricted hash.
49293501 241
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242=item Attempt to bless into a freed package
243
244(F) You wrote C<bless $foo> with one argument after somehow causing
245the current package to be freed. Perl cannot figure out what to
246do, so it throws up in hands in despair.
247
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248=item Attempt to bless into a reference
249
250(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 251the name of the package to bless the resulting object into. You've
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252supplied instead a reference to something: perhaps you wrote
253
254 bless $self, $proto;
255
256when you intended
257
258 bless $self, ref($proto) || $proto;
259
260If you actually want to bless into the stringified version
261of the reference supplied, you need to stringify it yourself, for
262example by:
263
264 bless $self, "$proto";
265
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266=item Attempt to clear deleted array
267
268(S debugging) An array was assigned to when it was being freed.
269Freed values are not supposed to be visible to Perl code. This
270can also happen if XS code calls C<av_clear> from a custom magic
271callback on the array.
272
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273=item Attempt to delete disallowed key '%s' from a restricted hash
274
275(F) The failing code attempted to delete from a restricted hash a key
276which is not in its key set.
277
278=item Attempt to delete readonly key '%s' from a restricted hash
279
280(F) The failing code attempted to delete a key whose value has been
281declared readonly from a restricted hash.
282
de42a5a9 283=item Attempt to free non-arena SV: 0x%x
a0d0e21e 284
f84fe999 285(S internal) All SV objects are supposed to be allocated from arenas
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286that will be garbage collected on exit. An SV was discovered to be
287outside any of those arenas.
a0d0e21e 288
12578ffb 289=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 290
f84fe999 291(S internal) Perl maintains a reference-counted internal table of
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292strings to optimize the storage and access of hash keys and other
293strings. This indicates someone tried to decrement the reference count
294of a string that can no longer be found in the table.
bbce6d69 295
7d5b40b4 296=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 297
f84fe999 298(S debugging) Mortalized values are supposed to be freed by the
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299free_tmps() routine. This indicates that something else is freeing the
300SV before the free_tmps() routine gets a chance, which means that the
301free_tmps() routine will be freeing an unreferenced scalar when it does
302try to free it.
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303
304=item Attempt to free unreferenced glob pointers
305
f84fe999 306(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 307
7d5b40b4 308=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 309
8f7e4d2c 310(S internal) Perl went to decrement the reference count of a scalar to
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311see if it would go to 0, and discovered that it had already gone to 0
312earlier, and should have been freed, and in fact, probably was freed.
313This could indicate that SvREFCNT_dec() was called too many times, or
314that SvREFCNT_inc() was called too few times, or that the SV was
315mortalized when it shouldn't have been, or that memory has been
316corrupted.
a0d0e21e 317
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318=item Attempt to pack pointer to temporary value
319
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320(W pack) You tried to pass a temporary value (like the result of a
321function, or a computed expression) to the "p" pack() template. This
322means the result contains a pointer to a location that could become
323invalid anytime, even before the end of the current statement. Use
324literals or global values as arguments to the "p" pack() template to
325avoid this warning.
84902520 326
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327=item Attempt to reload %s aborted.
328
329(F) You tried to load a file with C<use> or C<require> that failed to
330compile once already. Perl will not try to compile this file again
331unless you delete its entry from %INC. See L<perlfunc/require> and
332L<perlvar/%INC>.
333
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334=item Attempt to set length of freed array
335
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336(W misc) You tried to set the length of an array which has
337been freed. You can do this by storing a reference to the
338scalar representing the last index of an array and later
339assigning through that reference. For example
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340
341 $r = do {my @a; \$#a};
342 $$r = 503
343
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344=item Attempt to use reference as lvalue in substr
345
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346(W substr) You supplied a reference as the first argument to substr()
347used as an lvalue, which is pretty strange. Perhaps you forgot to
348dereference it first. See L<perlfunc/substr>.
b7a902f4 349
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NC
350=item Attribute "locked" is deprecated
351
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352(D deprecated) You have used the attributes pragma to modify the
353"locked" attribute on a code reference. The :locked attribute is
354obsolete, has had no effect since 5005 threads were removed, and
355will be removed in a future release of Perl 5.
c32124fe 356
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357=item Attribute prototype(%s) discards earlier prototype attribute in same sub
358
359(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
360example. Since each sub can only have one prototype, the earlier
361declaration(s) are discarded while the last one is applied.
362
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363=item Attribute "unique" is deprecated
364
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365(D deprecated) You have used the attributes pragma to modify
366the "unique" attribute on an array, hash or scalar reference.
367The :unique attribute has had no effect since Perl 5.8.8, and
368will be removed in a future release of Perl 5.
f1a3ce43 369
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370=item av_reify called on tied array
371
372(S debugging) This indicates that something went wrong and Perl got I<very>
373confused about C<@_> or C<@DB::args> being tied.
374
de42a5a9 375=item Bad arg length for %s, is %u, should be %d
a0d0e21e 376
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377(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
378or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 379S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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380S<sizeof(struct shmid_ds *)>.
381
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382=item Bad evalled substitution pattern
383
496a33f5 384(F) You've used the C</e> switch to evaluate the replacement for a
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385substitution, but perl found a syntax error in the code to evaluate,
386most likely an unexpected right brace '}'.
387
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388=item Bad filehandle: %s
389
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390(F) A symbol was passed to something wanting a filehandle, but the
391symbol has no filehandle associated with it. Perhaps you didn't do an
392open(), or did it in another package.
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393
394=item Bad free() ignored
395
be771a83 396(S malloc) An internal routine called free() on something that had never
fa816bf3 397been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 398setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 399
9ea8bc6d 400This message can be seen quite often with DB_File on systems with "hard"
6903afa2 401dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 402which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 403
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404=item Bad hash
405
406(P) One of the internal hash routines was passed a null HV pointer.
407
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408=item Badly placed ()'s
409
410(A) You've accidentally run your script through B<csh> instead
411of Perl. Check the #! line, or manually feed your script into
412Perl yourself.
413
a7cb8dae 414=item Bad name after %s
a0d0e21e 415
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416(F) You started to name a symbol by using a package prefix, and then
417didn't finish the symbol. In particular, you can't interpolate outside
418of quotes, so
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419
420 $var = 'myvar';
421 $sym = mypack::$var;
422
423is not the same as
424
425 $var = 'myvar';
426 $sym = "mypack::$var";
427
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428=item Bad plugin affecting keyword '%s'
429
430(F) An extension using the keyword plugin mechanism violated the
431plugin API.
432
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433=item Bad realloc() ignored
434
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435(S malloc) An internal routine called realloc() on something that
436had never been malloc()ed in the first place. Mandatory, but can
437be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 438
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439=item Bad symbol for array
440
441(P) An internal request asked to add an array entry to something that
442wasn't a symbol table entry.
443
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444=item Bad symbol for dirhandle
445
446(P) An internal request asked to add a dirhandle entry to something
447that wasn't a symbol table entry.
448
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449=item Bad symbol for filehandle
450
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451(P) An internal request asked to add a filehandle entry to something
452that wasn't a symbol table entry.
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453
454=item Bad symbol for hash
455
456(P) An internal request asked to add a hash entry to something that
457wasn't a symbol table entry.
458
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459=item Bareword found in conditional
460
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461(W bareword) The compiler found a bareword where it expected a
462conditional, which often indicates that an || or && was parsed as part
463of the last argument of the previous construct, for example:
34d09196
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464
465 open FOO || die;
466
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467It may also indicate a misspelled constant that has been interpreted as
468a bareword:
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469
470 use constant TYPO => 1;
471 if (TYOP) { print "foo" }
472
473The C<strict> pragma is useful in avoiding such errors.
474
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475=item Bareword "%s" not allowed while "strict subs" in use
476
477(F) With "strict subs" in use, a bareword is only allowed as a
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478subroutine identifier, in curly brackets or to the left of the "=>"
479symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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480
481=item Bareword "%s" refers to nonexistent package
482
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483(W bareword) You used a qualified bareword of the form C<Foo::>, but the
484compiler saw no other uses of that namespace before that point. Perhaps
485you need to predeclare a package?
6df41af2 486
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487=item BEGIN failed--compilation aborted
488
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489(F) An untrapped exception was raised while executing a BEGIN
490subroutine. Compilation stops immediately and the interpreter is
491exited.
a0d0e21e 492
68dc0745
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493=item BEGIN not safe after errors--compilation aborted
494
495(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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496implies a C<BEGIN {}>) after one or more compilation errors had already
497occurred. Since the intended environment for the C<BEGIN {}> could not
498be guaranteed (due to the errors), and since subsequent code likely
499depends on its correct operation, Perl just gave up.
68dc0745 500
c782d7ee 501=item \%d better written as $%d
6df41af2 502
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503(W syntax) Outside of patterns, backreferences live on as variables.
504The use of backslashes is grandfathered on the right-hand side of a
505substitution, but stylistically it's better to use the variable form
506because other Perl programmers will expect it, and it works better if
507there are more than 9 backreferences.
6df41af2 508
252aa082
JH
509=item Binary number > 0b11111111111111111111111111111111 non-portable
510
e476b1b5 511(W portable) The binary number you specified is larger than 2**32-1
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JH
512(4294967295) and therefore non-portable between systems. See
513L<perlport> for more on portability concerns.
252aa082 514
69282e91 515=item bind() on closed socket %s
a0d0e21e 516
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517(W closed) You tried to do a bind on a closed socket. Did you forget to
518check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 519
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520=item binmode() on closed filehandle %s
521
522(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 523Check your control flow and number of arguments.
c289d2f7 524
c5a0f51a
JH
525=item Bit vector size > 32 non-portable
526
e476b1b5 527(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 528
043c750c 529=item Bizarre copy of %s
4633a7c4 530
be771a83 531(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 532copiable.
4633a7c4 533
5a25739d
FC
534=item Bizarre SvTYPE [%d]
535
434f489b 536(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
537encountered an invalid data type.
538
f675dbe5
CB
539=item Buffer overflow in prime_env_iter: %s
540
be771a83
GS
541(W internal) A warning peculiar to VMS. While Perl was preparing to
542iterate over %ENV, it encountered a logical name or symbol definition
543which was too long, so it was truncated to the string shown.
f675dbe5 544
a0d0e21e
LW
545=item Callback called exit
546
4929bf7b 547(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
548exited by calling exit.
549
6df41af2 550=item %s() called too early to check prototype
f675dbe5 551
be771a83
GS
552(W prototype) You've called a function that has a prototype before the
553parser saw a definition or declaration for it, and Perl could not check
554that the call conforms to the prototype. You need to either add an
555early prototype declaration for the subroutine in question, or move the
556subroutine definition ahead of the call to get proper prototype
557checking. Alternatively, if you are certain that you're calling the
558function correctly, you may put an ampersand before the name to avoid
559the warning. See L<perlsub>.
f675dbe5 560
56feebad
FC
561=item Calling POSIX::%s() is deprecated
562
563(D deprecated) You called a function whose use is deprecated. See
564the function's name in L<POSIX> for details.
565
0c7df902
JH
566=item Cannot chr %f
567
568(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
569
5dee29d4 570=item Cannot compress %f in pack
0c7df902 571
5dee29d4
JH
572(F) You tried compressing an infinity or not-a-number as an unsigned
573integer with BER, which makes no sense.
0c7df902 574
49704364 575=item Cannot compress integer in pack
0258719b 576
717feafc
JH
577(F) An argument to pack("w",...) was too large to compress.
578The BER compressed integer format can only be used with positive
579integers, and you attempted to compress a very large number (> 1e308).
580See L<perlfunc/pack>.
0258719b 581
49704364 582=item Cannot compress negative numbers in pack
0258719b
NC
583
584(F) An argument to pack("w",...) was negative. The BER compressed integer
585format can only be used with positive integers. See L<perlfunc/pack>.
586
5c1f4d79
NC
587=item Cannot convert a reference to %s to typeglob
588
6903afa2
FC
589(F) You manipulated Perl's symbol table directly, stored a reference
590in it, then tried to access that symbol via conventional Perl syntax.
591The access triggers Perl to autovivify that typeglob, but it there is
592no legal conversion from that type of reference to a typeglob.
5c1f4d79 593
4040665a 594=item Cannot copy to %s
ba2fdce6
NC
595
596(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 597be directly assigned to.
ba2fdce6 598
b5d97229
RGS
599=item Cannot find encoding "%s"
600
601(S io) You tried to apply an encoding that did not exist to a filehandle,
602either with open() or binmode().
603
0c7df902
JH
604=item Cannot pack %f with '%c'
605
5dee29d4 606(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
607which makes no sense.
608
609=item Cannot printf %f with '%c'
610
611(F) You tried printing an infinity or not-a-number as a character (%c),
612which makes no sense. Maybe you meant '%s', or just stringifying it?
613
7355df7e
FC
614=item Cannot set tied @DB::args
615
616(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
617is not supported. (Before this error was added, it used to crash.)
618
ce65bc73
FC
619=item Cannot tie unreifiable array
620
621(P) You somehow managed to call C<tie> on an array that does not
622keep a reference count on its arguments and cannot be made to
623do so. Such arrays are not even supposed to be accessible to
624Perl code, but are only used internally.
625
96ebfdd7
RK
626=item Can only compress unsigned integers in pack
627
628(F) An argument to pack("w",...) was not an integer. The BER compressed
629integer format can only be used with positive integers, and you attempted
630to compress something else. See L<perlfunc/pack>.
631
a0d0e21e
LW
632=item Can't bless non-reference value
633
634(F) Only hard references may be blessed. This is how Perl "enforces"
635encapsulation of objects. See L<perlobj>.
636
dc57907a
RGS
637=item Can't "break" in a loop topicalizer
638
0d863452 639(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 640a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
641
642=item Can't "break" outside a given block
dc57907a 643
0d863452
RH
644(F) You called C<break>, but you're not inside a C<given> block.
645
6df41af2
GS
646=item Can't call method "%s" on an undefined value
647
648(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
649object reference or package name contains an undefined value. Something
650like this will reproduce the error:
6df41af2
GS
651
652 $BADREF = undef;
653 process $BADREF 1,2,3;
654 $BADREF->process(1,2,3);
655
a0d0e21e
LW
656=item Can't call method "%s" on unblessed reference
657
54310121 658(F) A method call must know in what package it's supposed to run. It
be771a83
GS
659ordinarily finds this out from the object reference you supply, but you
660didn't supply an object reference in this case. A reference isn't an
661object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
662
663=item Can't call method "%s" without a package or object reference
664
665(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
666object reference or package name contains an expression that returns a
667defined value which is neither an object reference nor a package name.
72b5445b
GS
668Something like this will reproduce the error:
669
670 $BADREF = 42;
671 process $BADREF 1,2,3;
672 $BADREF->process(1,2,3);
673
dfe378f1
FC
674=item Can't call mro_isa_changed_in() on anonymous symbol table
675
676(P) Perl got confused as to whether a hash was a plain hash or a
677symbol table hash when trying to update @ISA caches.
678
2bf7e7b2
FC
679=item Can't call mro_method_changed_in() on anonymous symbol table
680
681(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
682not attached to the symbol table.
683
a0d0e21e
LW
684=item Can't chdir to %s
685
f703fc96 686(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
687that you can chdir to, possibly because it doesn't exist.
688
0545a864 689=item Can't check filesystem of script "%s" for nosuid
104d25b7 690
be771a83
GS
691(P) For some reason you can't check the filesystem of the script for
692nosuid.
104d25b7 693
22e74366 694=item Can't coerce %s to %s in %s
a0d0e21e
LW
695
696(F) Certain types of SVs, in particular real symbol table entries
55497cff 697(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
698say things like:
699
700 *foo += 1;
701
702You CAN say
703
704 $foo = *foo;
705 $foo += 1;
706
707but then $foo no longer contains a glob.
708
0d863452 709=item Can't "continue" outside a when block
dc57907a 710
0d863452
RH
711(F) You called C<continue>, but you're not inside a C<when>
712or C<default> block.
713
a0d0e21e
LW
714=item Can't create pipe mailbox
715
be771a83
GS
716(P) An error peculiar to VMS. The process is suffering from exhausted
717quotas or other plumbing problems.
a0d0e21e 718
eb64745e
GS
719=item Can't declare %s in "%s"
720
30c282f6
NC
721(F) Only scalar, array, and hash variables may be declared as "my", "our" or
722"state" variables. They must have ordinary identifiers as names.
a0d0e21e 723
fc7debfb
FC
724=item Can't "default" outside a topicalizer
725
726(F) You have used a C<default> block that is neither inside a
727C<foreach> loop nor a C<given> block. (Note that this error is
728issued on exit from the C<default> block, so you won't get the
729error if you use an explicit C<continue>.)
730
6df41af2
GS
731=item Can't do inplace edit: %s is not a regular file
732
be771a83 733(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 734a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 735
a0d0e21e
LW
736=item Can't do inplace edit on %s: %s
737
be771a83
GS
738(S inplace) The creation of the new file failed for the indicated
739reason.
a0d0e21e 740
54310121 741=item Can't do inplace edit without backup
a0d0e21e 742
be771a83
GS
743(F) You're on a system such as MS-DOS that gets confused if you try
744reading from a deleted (but still opened) file. You have to say
745C<-i.bak>, or some such.
a0d0e21e 746
10f9c03d 747=item Can't do inplace edit: %s would not be unique
a0d0e21e 748
e476b1b5 749(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
750characters and Perl was unable to create a unique filename during
751inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 752
a0d0e21e
LW
753=item Can't do waitpid with flags
754
be771a83
GS
755(F) This machine doesn't have either waitpid() or wait4(), so only
756waitpid() without flags is emulated.
a0d0e21e 757
a0d0e21e
LW
758=item Can't emulate -%s on #! line
759
be771a83
GS
760(F) The #! line specifies a switch that doesn't make sense at this
761point. For example, it'd be kind of silly to put a B<-x> on the #!
762line.
a0d0e21e 763
1109a392
MHM
764=item Can't %s %s-endian %ss on this platform
765
766(F) Your platform's byte-order is neither big-endian nor little-endian,
767or it has a very strange pointer size. Packing and unpacking big- or
768little-endian floating point values and pointers may not be possible.
769See L<perlfunc/pack>.
770
a0d0e21e
LW
771=item Can't exec "%s": %s
772
d1be9408 773(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
774named program for the indicated reason. Typical reasons include: the
775permissions were wrong on the file, the file wasn't found in
776C<$ENV{PATH}>, the executable in question was compiled for another
777architecture, or the #! line in a script points to an interpreter that
778can't be run for similar reasons. (Or maybe your system doesn't support
779#! at all.)
a0d0e21e
LW
780
781=item Can't exec %s
782
be771a83
GS
783(F) Perl was trying to execute the indicated program for you because
784that's what the #! line said. If that's not what you wanted, you may
785need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
786
787=item Can't execute %s
788
be771a83
GS
789(F) You used the B<-S> switch, but the copies of the script to execute
790found in the PATH did not have correct permissions.
2a92aaa0 791
6df41af2 792=item Can't find an opnumber for "%s"
2a92aaa0 793
be771a83
GS
794(F) A string of a form C<CORE::word> was given to prototype(), but there
795is no builtin with the name C<word>.
6df41af2 796
56ca2fc0
JH
797=item Can't find %s character property "%s"
798
799(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 800could not be found. Maybe you misspelled the name of the property?
e1b711da 801See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 802for a complete list of available official properties.
56ca2fc0 803
6df41af2
GS
804=item Can't find label %s
805
be771a83
GS
806(F) You said to goto a label that isn't mentioned anywhere that it's
807possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
808
809=item Can't find %s on PATH
810
be771a83
GS
811(F) You used the B<-S> switch, but the script to execute could not be
812found in the PATH.
a0d0e21e 813
6df41af2 814=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 815
be771a83
GS
816(F) You used the B<-S> switch, but the script to execute could not be
817found in the PATH, or at least not with the correct permissions. The
818script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
819
820=item Can't find string terminator %s anywhere before EOF
821
be771a83
GS
822(F) Perl strings can stretch over multiple lines. This message means
823that the closing delimiter was omitted. Because bracketed quotes count
824nesting levels, the following is missing its final parenthesis:
a0d0e21e 825
fb73857a
PP
826 print q(The character '(' starts a side comment.);
827
97b3d10f 828If you're getting this error from a here-document, you may have
b6b8cb97
FC
829included unseen whitespace before or after your closing tag or there
830may not be a linebreak after it. A good programmer's editor will have
831a way to help you find these characters (or lack of characters). See
832L<perlop> for the full details on here-documents.
a0d0e21e 833
660a4616
ST
834=item Can't find Unicode property definition "%s"
835
5f8ad6b6
FC
836(F) You may have tried to use C<\p> which means a Unicode
837property (for example C<\p{Lu}> matches all uppercase
fa816bf3 838letters). If you did mean to use a Unicode property, see
e1b711da 839L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 840for a complete list of available properties. If you didn't
fa816bf3
FC
841mean to use a Unicode property, escape the C<\p>, either by
842C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 843until C<\E>).
660a4616 844
b3647a36 845=item Can't fork: %s
a0d0e21e 846
be771a83
GS
847(F) A fatal error occurred while trying to fork while opening a
848pipeline.
a0d0e21e 849
b3647a36
SR
850=item Can't fork, trying again in 5 seconds
851
c973c02e 852(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
853after five seconds.
854
748a9306
LW
855=item Can't get filespec - stale stat buffer?
856
be771a83
GS
857(S) A warning peculiar to VMS. This arises because of the difference
858between access checks under VMS and under the Unix model Perl assumes.
859Under VMS, access checks are done by filename, rather than by bits in
860the stat buffer, so that ACLs and other protections can be taken into
861account. Unfortunately, Perl assumes that the stat buffer contains all
862the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 863the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
864the device name and FID present in the stat buffer, but this works only
865if you haven't made a subsequent call to the CRTL stat() routine,
866because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
867appears, the name lookup failed, and the access-checking routine gave up
868and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
869routine knows about the Perl C<stat> operator and file tests, so you
870shouldn't ever see this warning in response to a Perl command; it arises
871only if some internal code takes stat buffers lightly.)
748a9306 872
a0d0e21e
LW
873=item Can't get pipe mailbox device name
874
be771a83
GS
875(P) An error peculiar to VMS. After creating a mailbox to act as a
876pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
877
878=item Can't get SYSGEN parameter value for MAXBUF
879
748a9306
LW
880(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
881mailbox buffers to be, and didn't get an answer.
a0d0e21e 882
6df41af2 883=item Can't "goto" into the middle of a foreach loop
a0d0e21e 884
be771a83
GS
885(F) A "goto" statement was executed to jump into the middle of a foreach
886loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
887
888=item Can't "goto" out of a pseudo block
889
be771a83
GS
890(F) A "goto" statement was executed to jump out of what might look like
891a block, except that it isn't a proper block. This usually occurs if
892you tried to jump out of a sort() block or subroutine, which is a no-no.
893See L<perlfunc/goto>.
a0d0e21e 894
5a25739d
FC
895=item Can't goto subroutine from an eval-%s
896
897(F) The "goto subroutine" call can't be used to jump out of an eval
898"string" or block.
899
9850bf21 900=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 901
9850bf21
RH
902(F) The "goto subroutine" call can't be used to jump out of the
903comparison sub for a sort(), or from a similar callback (such
904as the reduce() function in List::Util).
905
6df41af2
GS
906=item Can't goto subroutine outside a subroutine
907
be771a83
GS
908(F) The deeply magical "goto subroutine" call can only replace one
909subroutine call for another. It can't manufacture one out of whole
910cloth. In general you should be calling it out of only an AUTOLOAD
911routine anyway. See L<perlfunc/goto>.
6df41af2 912
0b5b802d
GS
913=item Can't ignore signal CHLD, forcing to default
914
be771a83
GS
915(W signal) Perl has detected that it is being run with the SIGCHLD
916signal (sometimes known as SIGCLD) disabled. Since disabling this
917signal will interfere with proper determination of exit status of child
918processes, Perl has reset the signal to its default value. This
919situation typically indicates that the parent program under which Perl
920may be running (e.g. cron) is being very careless.
0b5b802d 921
e2c0f81f
DG
922=item Can't kill a non-numeric process ID
923
924(F) Process identifiers must be (signed) integers. It is a fatal error to
925attempt to kill() an undefined, empty-string or otherwise non-numeric
926process identifier.
927
6df41af2 928=item Can't "last" outside a loop block
4633a7c4 929
6df41af2 930(F) A "last" statement was executed to break out of the current block,
be771a83
GS
931except that there's this itty bitty problem called there isn't a current
932block. Note that an "if" or "else" block doesn't count as a "loopish"
933block, as doesn't a block given to sort(), map() or grep(). You can
934usually double the curlies to get the same effect though, because the
935inner curlies will be considered a block that loops once. See
936L<perlfunc/last>.
4633a7c4 937
2c7d6b9c
RGS
938=item Can't linearize anonymous symbol table
939
940(F) Perl tried to calculate the method resolution order (MRO) of a
941package, but failed because the package stash has no name.
942
b8170e59
JB
943=item Can't load '%s' for module %s
944
6903afa2
FC
945(F) The module you tried to load failed to load a dynamic extension.
946This may either mean that you upgraded your version of perl to one
947that is incompatible with your old dynamic extensions (which is known
948to happen between major versions of perl), or (more likely) that your
949dynamic extension was built against an older version of the library
950that is installed on your system. You may need to rebuild your old
951dynamic extensions.
b8170e59 952
748a9306
LW
953=item Can't localize lexical variable %s
954
2ba9eb46 955(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
956lexical variable using "my" or "state". This is not allowed. If you
957want to localize a package variable of the same name, qualify it with
958the package name.
748a9306 959
6df41af2 960=item Can't localize through a reference
4727527e 961
6df41af2
GS
962(F) You said something like C<local $$ref>, which Perl can't currently
963handle, because when it goes to restore the old value of whatever $ref
be771a83 964pointed to after the scope of the local() is finished, it can't be sure
64977eb6 965that $ref will still be a reference.
4727527e 966
ea071790 967=item Can't locate %s
ec889f3a 968
fa816bf3
FC
969(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
970Perl looks for the file in all the locations mentioned in @INC, unless
971the file name included the full path to the file. Perhaps you need
972to set the PERL5LIB or PERL5OPT environment variable to say where the
973extra library is, or maybe the script needs to add the library name
be771a83
GS
974to @INC. Or maybe you just misspelled the name of the file. See
975L<perlfunc/require> and L<lib>.
a0d0e21e 976
6df41af2
GS
977=item Can't locate auto/%s.al in @INC
978
be771a83
GS
979(F) A function (or method) was called in a package which allows
980autoload, but there is no function to autoload. Most probable causes
981are a misprint in a function/method name or a failure to C<AutoSplit>
982the file, say, by doing C<make install>.
6df41af2 983
b8170e59
JB
984=item Can't locate loadable object for module %s in @INC
985
986(F) The module you loaded is trying to load an external library, like
d70d8e57 987for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
988unable to locate this library. See L<DynaLoader>.
989
a0d0e21e
LW
990=item Can't locate object method "%s" via package "%s"
991
992(F) You called a method correctly, and it correctly indicated a package
993functioning as a class, but that package doesn't define that particular
2ba9eb46 994method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 995
8af56b9d
FC
996=item Can't locate object method "%s" via package "%s" (perhaps you forgot
997to load "%s"?)
998
999(F) You called a method on a class that did not exist, and the method
1000could not be found in UNIVERSAL. This often means that a method
1001requires a package that has not been loaded.
1002
a0d0e21e
LW
1003=item Can't locate package %s for @%s::ISA
1004
be771a83
GS
1005(W syntax) The @ISA array contained the name of another package that
1006doesn't seem to exist.
a0d0e21e 1007
2f7da168
RK
1008=item Can't locate PerlIO%s
1009
1010(F) You tried to use in open() a PerlIO layer that does not exist,
1011e.g. open(FH, ">:nosuchlayer", "somefile").
1012
f4ad53f4 1013=item Can't make list assignment to %ENV on this system
3e3baf6d 1014
be771a83
GS
1015(F) List assignment to %ENV is not supported on some systems, notably
1016VMS.
3e3baf6d 1017
cd40cd58
NC
1018=item Can't make loaded symbols global on this platform while loading %s
1019
ff9c1ae8 1020(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1021that symbols from the stated file are made available globally within the
1022process, but that functionality is not available on this platform. Whilst
1023the module likely will still work, this may prevent the perl interpreter
1024from loading other XS-based extensions which need to link directly to
1025functions defined in the C or XS code in the stated file.
1026
a0d0e21e
LW
1027=item Can't modify %s in %s
1028
be771a83
GS
1029(F) You aren't allowed to assign to the item indicated, or otherwise try
1030to change it, such as with an auto-increment.
a0d0e21e 1031
54310121 1032=item Can't modify nonexistent substring
a0d0e21e
LW
1033
1034(P) The internal routine that does assignment to a substr() was handed
1035a NULL.
1036
6df41af2
GS
1037=item Can't modify non-lvalue subroutine call
1038
1039(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1040such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1041
5f05dabc 1042=item Can't msgrcv to read-only var
a0d0e21e 1043
5f05dabc 1044(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1045buffer.
1046
6df41af2
GS
1047=item Can't "next" outside a loop block
1048
1049(F) A "next" statement was executed to reiterate the current block, but
1050there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1051count as a "loopish" block, as doesn't a block given to sort(), map() or
1052grep(). You can usually double the curlies to get the same effect
1053though, because the inner curlies will be considered a block that loops
1054once. See L<perlfunc/next>.
6df41af2 1055
a0d0e21e
LW
1056=item Can't open %s: %s
1057
c47ff5f1 1058(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1059filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1060switches, or explicitly, failed for the indicated reason. Usually
1061this is because you don't have read permission for a file which
1062you named on the command line.
1063
1064(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1065your operating system's equivalent) could not be opened.
a0d0e21e 1066
9a869a14
RGS
1067=item Can't open a reference
1068
1069(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1070using the 3-arg open() syntax:
9a869a14
RGS
1071
1072 open FH, '>', $ref;
1073
1074but your version of perl is compiled without perlio, and this form of
1075open is not supported.
1076
a0d0e21e
LW
1077=item Can't open bidirectional pipe
1078
be771a83
GS
1079(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1080You can try any of several modules in the Perl library to do this, such
1081as IPC::Open2. Alternately, direct the pipe's output to a file using
1082">", and then read it in under a different file handle.
a0d0e21e 1083
748a9306
LW
1084=item Can't open error file %s as stderr
1085
be771a83
GS
1086(F) An error peculiar to VMS. Perl does its own command line
1087redirection, and couldn't open the file specified after '2>' or '2>>' on
1088the command line for writing.
748a9306
LW
1089
1090=item Can't open input file %s as stdin
1091
be771a83
GS
1092(F) An error peculiar to VMS. Perl does its own command line
1093redirection, and couldn't open the file specified after '<' on the
1094command line for reading.
748a9306
LW
1095
1096=item Can't open output file %s as stdout
1097
be771a83
GS
1098(F) An error peculiar to VMS. Perl does its own command line
1099redirection, and couldn't open the file specified after '>' or '>>' on
1100the command line for writing.
748a9306
LW
1101
1102=item Can't open output pipe (name: %s)
1103
be771a83
GS
1104(P) An error peculiar to VMS. Perl does its own command line
1105redirection, and couldn't open the pipe into which to send data destined
1106for stdout.
748a9306 1107
3b1cf97d 1108=item Can't open perl script "%s": %s
a0d0e21e
LW
1109
1110(F) The script you specified can't be opened for the indicated reason.
1111
fa3aa65a
JC
1112If you're debugging a script that uses #!, and normally relies on the
1113shell's $PATH search, the -S option causes perl to do that search, so
1114you don't have to type the path or C<`which $scriptname`>.
1115
6df41af2
GS
1116=item Can't read CRTL environ
1117
1118(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1119from the CRTL's internal environment array and discovered the array was
1120missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1121or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1122searched.
6df41af2 1123
6df41af2
GS
1124=item Can't "redo" outside a loop block
1125
1126(F) A "redo" statement was executed to restart the current block, but
1127there isn't a current block. Note that an "if" or "else" block doesn't
1128count as a "loopish" block, as doesn't a block given to sort(), map()
1129or grep(). You can usually double the curlies to get the same effect
1130though, because the inner curlies will be considered a block that
1131loops once. See L<perlfunc/redo>.
1132
64977eb6 1133=item Can't remove %s: %s, skipping file
10f9c03d 1134
be771a83
GS
1135(S inplace) You requested an inplace edit without creating a backup
1136file. Perl was unable to remove the original file to replace it with
1137the modified file. The file was left unmodified.
10f9c03d 1138
a0d0e21e
LW
1139=item Can't rename %s to %s: %s, skipping file
1140
e476b1b5 1141(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1142probably because you don't have write permission to the directory.
a0d0e21e 1143
748a9306
LW
1144=item Can't reopen input pipe (name: %s) in binary mode
1145
be771a83
GS
1146(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1147to reopen it to accept binary data. Alas, it failed.
748a9306 1148
4f12ec0e
FC
1149=item Can't reset %ENV on this system
1150
1151(F) You called C<reset('E')> or similar, which tried to reset
1152all variables in the current package beginning with "E". In
1153the main package, that includes %ENV. Resetting %ENV is not
1154supported on some systems, notably VMS.
1155
fe13d51d 1156=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1157
1fa582fa
FC
1158(F)(P) Error resolving overloading specified by a method name (as
1159opposed to a subroutine reference): no such method callable via the
1160package. If the method name is C<???>, this is an internal error.
6df41af2 1161
cd06dffe
GS
1162=item Can't return %s from lvalue subroutine
1163
be771a83
GS
1164(F) Perl detected an attempt to return illegal lvalues (such as
1165temporary or readonly values) from a subroutine used as an lvalue. This
1166is not allowed.
cd06dffe 1167
96ebfdd7
RK
1168=item Can't return outside a subroutine
1169
1170(F) The return statement was executed in mainline code, that is, where
1171there was no subroutine call to return out of. See L<perlsub>.
1172
78f9721b
SM
1173=item Can't return %s to lvalue scalar context
1174
6903afa2
FC
1175(F) You tried to return a complete array or hash from an lvalue
1176subroutine, but you called the subroutine in a way that made Perl
1177think you meant to return only one value. You probably meant to
1178write parentheses around the call to the subroutine, which tell
1179Perl that the call should be in list context.
78f9721b 1180
a0d0e21e
LW
1181=item Can't stat script "%s"
1182
be771a83
GS
1183(P) For some reason you can't fstat() the script even though you have it
1184open already. Bizarre.
a0d0e21e 1185
a0d0e21e
LW
1186=item Can't take log of %g
1187
fb73857a 1188(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1189negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1190standard with Perl, though, if you really want to do that for the
1191negative numbers.
a0d0e21e
LW
1192
1193=item Can't take sqrt of %g
1194
1195(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1196negative number. There's a Math::Complex package that comes standard
1197with Perl, though, if you really want to do that.
a0d0e21e
LW
1198
1199=item Can't undef active subroutine
1200
1201(F) You can't undefine a routine that's currently running. You can,
1202however, redefine it while it's running, and you can even undef the
1203redefined subroutine while the old routine is running. Go figure.
1204
c81225bc 1205=item Can't upgrade %s (%d) to %d
a0d0e21e 1206
be771a83
GS
1207(P) The internal sv_upgrade routine adds "members" to an SV, making it
1208into a more specialized kind of SV. The top several SV types are so
1209specialized, however, that they cannot be interconverted. This message
1210indicates that such a conversion was attempted.
a0d0e21e 1211
6651ba0b
FC
1212=item Can't use '%c' after -mname
1213
1214(F) You tried to call perl with the B<-m> switch, but you put something
1215other than "=" after the module name.
1216
1f1ec7b5
KW
1217=item Can't use a hash as a reference
1218
1219(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1220C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1221<= 5.22.0 used to allow this syntax, but shouldn't
1222have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1223
1224=item Can't use an array as a reference
1225
1226(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1227C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1228used to allow this syntax, but shouldn't have. This
1229was deprecated in perl 5.6.1.
1f1ec7b5 1230
1db89ea5
BS
1231=item Can't use anonymous symbol table for method lookup
1232
e27ad1f2 1233(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1234table that doesn't have a name. Symbol tables can become anonymous
1235for example by undefining stashes: C<undef %Some::Package::>.
1236
96ebfdd7
RK
1237=item Can't use an undefined value as %s reference
1238
1239(F) A value used as either a hard reference or a symbolic reference must
1240be a defined value. This helps to delurk some insidious errors.
1241
6df41af2
GS
1242=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1243
be771a83
GS
1244(F) Only hard references are allowed by "strict refs". Symbolic
1245references are disallowed. See L<perlref>.
6df41af2 1246
90b75b61 1247=item Can't use %! because Errno.pm is not available
1d2dff63 1248
20561843 1249(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1250Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1251provide symbolic names for C<$!> errno values.
1252
1109a392
MHM
1253=item Can't use both '<' and '>' after type '%c' in %s
1254
1255(F) A type cannot be forced to have both big-endian and little-endian
1256byte-order at the same time, so this combination of modifiers is not
1257allowed. See L<perlfunc/pack>.
1258
e35475de
KW
1259=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1260
1261(F) defined() is not useful on arrays because it
1262checks for an undefined I<scalar> value. If you want to see if the
1263array is empty, just use C<if (@array) { # not empty }> for example.
1264
1265=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1266
1267(F) C<defined()> is not usually right on hashes.
1268
1269Although C<defined %hash> is false on a plain not-yet-used hash, it
1270becomes true in several non-obvious circumstances, including iterators,
1271weak references, stash names, even remaining true after C<undef %hash>.
1272These things make C<defined %hash> fairly useless in practice, so it now
1273generates a fatal error.
1274
1275If a check for non-empty is what you wanted then just put it in boolean
1276context (see L<perldata/Scalar values>):
1277
1278 if (%hash) {
1279 # not empty
1280 }
1281
1282If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1283variable exists then that's never really been reliable, and isn't
1284a good way to enquire about the features of a package, or whether
1285it's loaded, etc.
1286
6df41af2
GS
1287=item Can't use %s for loop variable
1288
be771a83
GS
1289(F) Only a simple scalar variable may be used as a loop variable on a
1290foreach.
6df41af2 1291
aab6a793 1292=item Can't use global %s in "%s"
6df41af2 1293
be771a83
GS
1294(F) You tried to declare a magical variable as a lexical variable. This
1295is not allowed, because the magic can be tied to only one location
1296(namely the global variable) and it would be incredibly confusing to
1297have variables in your program that looked like magical variables but
6df41af2
GS
1298weren't.
1299
6d3b25aa
RGS
1300=item Can't use '%c' in a group with different byte-order in %s
1301
1302(F) You attempted to force a different byte-order on a type
1303that is already inside a group with a byte-order modifier.
1304For example you cannot force little-endianness on a type that
1305is inside a big-endian group.
1306
c07a80fd
PP
1307=item Can't use "my %s" in sort comparison
1308
1309(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1310You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1311and the variable had earlier been declared as a lexical variable.
1312Either qualify the sort variable with the package name, or rename the
1313lexical variable.
1314
a0d0e21e
LW
1315=item Can't use %s ref as %s ref
1316
1317(F) You've mixed up your reference types. You have to dereference a
1318reference of the type needed. You can use the ref() function to
1319test the type of the reference, if need be.
1320
748a9306 1321=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1322
5e634d20
FC
1323=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1324
b41bf23f
FC
1325(F) You've told Perl to dereference a string, something which
1326C<use strict> blocks to prevent it happening accidentally. See
1327L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1328in a double-quoted string immediately before interpolating a variable,
1329for example in C<"user @$twitter_id">, which says to treat the contents
1330of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1331symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1332
748a9306
LW
1333=item Can't use subscript on %s
1334
1335(F) The compiler tried to interpret a bracketed expression as a
1336subscript. But to the left of the brackets was an expression that
209e7cf1 1337didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1338
6df41af2
GS
1339=item Can't use \%c to mean $%c in expression
1340
75b44862
GS
1341(W syntax) In an ordinary expression, backslash is a unary operator that
1342creates a reference to its argument. The use of backslash to indicate a
1343backreference to a matched substring is valid only as part of a regular
be771a83
GS
1344expression pattern. Trying to do this in ordinary Perl code produces a
1345value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1346instead.
6df41af2 1347
810b8aa5
GS
1348=item Can't weaken a nonreference
1349
1350(F) You attempted to weaken something that was not a reference. Only
1351references can be weakened.
1352
fc7debfb
FC
1353=item Can't "when" outside a topicalizer
1354
1355(F) You have used a when() block that is neither inside a C<foreach>
1356loop nor a C<given> block. (Note that this error is issued on exit
1357from the C<when> block, so you won't get the error if the match fails,
1358or if you use an explicit C<continue>.)
1359
5f05dabc 1360=item Can't x= to read-only value
a0d0e21e 1361
be771a83
GS
1362(F) You tried to repeat a constant value (often the undefined value)
1363with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1364Perhaps you need to copy the value to a temporary, and repeat that.
1365
a04e6aad 1366=item Character following "\c" must be printable ASCII
f9d13529 1367
7357bd17 1368(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1369
727b6379 1370Note that ASCII characters that don't map to control characters are
7357bd17 1371discouraged, and will generate the warning (when enabled)
727b6379 1372L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1373
f337b084 1374=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1375
1376(W pack) You said
1377
1378 pack("C", $x)
1379
1380where $x is either less than 0 or more than 255; the C<"C"> format is
1381only for encoding native operating system characters (ASCII, EBCDIC,
1382and so on) and not for Unicode characters, so Perl behaved as if you meant
1383
1384 pack("C", $x & 255)
1385
1386If you actually want to pack Unicode codepoints, use the C<"U"> format
1387instead.
1388
f337b084 1389=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1390
1391(W pack) You said
1392
1393 pack("c", $x)
1394
1395where $x is either less than -128 or more than 127; the C<"c"> format
1396is only for encoding native operating system characters (ASCII, EBCDIC,
1397and so on) and not for Unicode characters, so Perl behaved as if you meant
1398
1399 pack("c", $x & 255);
1400
1401If you actually want to pack Unicode codepoints, use the C<"U"> format
1402instead.
1403
f337b084
TH
1404=item Character in '%c' format wrapped in unpack
1405
1406(W unpack) You tried something like
1407
1408 unpack("H", "\x{2a1}")
1409
1a147d38 1410where the format expects to process a byte (a character with a value
6903afa2
FC
1411below 256), but a higher value was provided instead. Perl uses the
1412value modulus 256 instead, as if you had provided:
f337b084
TH
1413
1414 unpack("H", "\x{a1}")
1415
5a25739d
FC
1416=item Character in 'W' format wrapped in pack
1417
1418(W pack) You said
1419
1420 pack("U0W", $x)
1421
1422where $x is either less than 0 or more than 255. However, C<U0>-mode
1423expects all values to fall in the interval [0, 255], so Perl behaved
1424as if you meant:
1425
1426 pack("U0W", $x & 255)
1427
f337b084
TH
1428=item Character(s) in '%c' format wrapped in pack
1429
1430(W pack) You tried something like
1431
1432 pack("u", "\x{1f3}b")
1433
1a147d38 1434where the format expects to process a sequence of bytes (character with a
6903afa2 1435value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1436uses the character values modulus 256 instead, as if you had provided:
1437
1438 pack("u", "\x{f3}b")
1439
1440=item Character(s) in '%c' format wrapped in unpack
1441
1442(W unpack) You tried something like
1443
1444 unpack("s", "\x{1f3}b")
1445
1a147d38 1446where the format expects to process a sequence of bytes (character with a
6903afa2 1447value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1448uses the character values modulus 256 instead, as if you had provided:
1449
1450 unpack("s", "\x{f3}b")
1451
f51551f7
FC
1452=item charnames alias definitions may not contain a sequence of multiple spaces
1453
1454(F) You defined a character name which had multiple space characters
1455in a row. Change them to single spaces. Usually these names are
1456defined in the C<:alias> import argument to C<use charnames>, but they
1457could be defined by a translator installed into C<$^H{charnames}>. See
1458L<charnames/CUSTOM ALIASES>.
1459
1460=item charnames alias definitions may not contain trailing white-space
1461
1462(F) You defined a character name which ended in a space
1463character. Remove the trailing space(s). Usually these names are
1464defined in the C<:alias> import argument to C<use charnames>, but they
1465could be defined by a translator installed into C<$^H{charnames}>.
1466See L<charnames/CUSTOM ALIASES>.
1467
1468=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1469
1470(D deprecated, regexp) The \C character class is deprecated, and will
1471become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1472v5.24). This construct allows you to match a single byte of what makes
1473up a multi-byte single UTF8 character, and breaks encapsulation. It is
1474currently also very buggy. If you really need to process the individual
f51551f7
FC
1475bytes, you probably want to convert your string to one where each
1476underlying byte is stored as a character, with utf8::encode().
1477
f866a7cd
FC
1478=item "\c%c" is more clearly written simply as "%s"
1479
1480(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1481non-printable characters. You used it for a printable one, which
1482is better written as simply itself, perhaps preceded by a backslash
1483for non-word characters. Doing it the way you did is not portable
1484between ASCII and EBCDIC platforms.
f866a7cd 1485
6651ba0b
FC
1486=item Cloning substitution context is unimplemented
1487
1488(F) Creating a new thread inside the C<s///> operator is not supported.
1489
abc7ecad
SP
1490=item closedir() attempted on invalid dirhandle %s
1491
1492(W io) The dirhandle you tried to close is either closed or not really
1493a dirhandle. Check your control flow.
1494
5a25739d
FC
1495=item close() on unopened filehandle %s
1496
1497(W unopened) You tried to close a filehandle that was never opened.
1498
541ed3a9
FC
1499=item Closure prototype called
1500
1501(F) If a closure has attributes, the subroutine passed to an attribute
1502handler is the prototype that is cloned when a new closure is created.
1503This subroutine cannot be called.
1504
49704364
LW
1505=item Code missing after '/'
1506
6903afa2
FC
1507(F) You had a (sub-)template that ends with a '/'. There must be
1508another template code following the slash. See L<perlfunc/pack>.
49704364 1509
5a25739d
FC
1510=item Code point 0x%X is not Unicode, may not be portable
1511
2d88a86a 1512(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1513of U+10FFFF.
1514
1515Perl allows strings to contain a superset of Unicode code points, up
1516to the limit of what is storable in an unsigned integer on your system,
1517but these may not be accepted by other languages/systems. At one time,
1518it was legal in some standards to have code points up to 0x7FFF_FFFF,
1519but not higher. Code points above 0xFFFF_FFFF require larger than a
152032 bit word.
0876b9a0 1521
6df41af2
GS
1522=item %s: Command not found
1523
a892b81a 1524(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1525instead of Perl. Check the #! line, or manually feed your script into
1526Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1527
1528 #!/usr/bin/perl -w
6df41af2 1529
7a2e2cd6
PP
1530=item Compilation failed in require
1531
1532(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1533Perl uses this generic message when none of the errors that it
1534encountered were severe enough to halt compilation immediately.
7a2e2cd6 1535
c3464db5
DD
1536=item Complex regular subexpression recursion limit (%d) exceeded
1537
be771a83
GS
1538(W regexp) The regular expression engine uses recursion in complex
1539situations where back-tracking is required. Recursion depth is limited
1540to 32766, or perhaps less in architectures where the stack cannot grow
1541arbitrarily. ("Simple" and "medium" situations are handled without
1542recursion and are not subject to a limit.) Try shortening the string
1543under examination; looping in Perl code (e.g. with C<while>) rather than
1544in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1545that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1546on I<Mastering Regular Expressions>.)
c3464db5 1547
69282e91 1548=item connect() on closed socket %s
a0d0e21e 1549
be771a83
GS
1550(W closed) You tried to do a connect on a closed socket. Did you forget
1551to check the return value of your socket() call? See
1552L<perlfunc/connect>.
a0d0e21e 1553
e21e7c6a
FC
1554=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1555
1556(F) The subroutine registered to handle constant overloading
1557(see L<overload>) or a custom charnames handler (see
1558L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1559
1560=item Constant(%s): $^H{%s} is not defined
1561
1562(F) The parser found inconsistencies while attempting to define an
1563overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1564L<overload> pragma?
e21e7c6a 1565
779c5bc9
GS
1566=item Constant is not %s reference
1567
1568(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1569is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1570The message indicates the type of reference that was expected. This
be771a83 1571usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1572See L<perlsub/"Constant Functions"> and L<constant>.
1573
4cee8e80
CS
1574=item Constant subroutine %s redefined
1575
aeb94125
FC
1576(W redefine)(S) You redefined a subroutine which had previously
1577been eligible for inlining. See L<perlsub/"Constant Functions">
1578for commentary and workarounds.
4cee8e80 1579
9607fc9c
PP
1580=item Constant subroutine %s undefined
1581
be771a83
GS
1582(W misc) You undefined a subroutine which had previously been eligible
1583for inlining. See L<perlsub/"Constant Functions"> for commentary and
1584workarounds.
9607fc9c 1585
5a25739d
FC
1586=item Constant(%s) unknown
1587
1588(F) The parser found inconsistencies either while attempting
1589to define an overloaded constant, or when trying to find the
1590character name specified in the C<\N{...}> escape. Perhaps you
1591forgot to load the corresponding L<overload> pragma?.
1592
e7ea3e70
IZ
1593=item Copy method did not return a reference
1594
6903afa2 1595(F) The method which overloads "=" is buggy. See
13a2d996 1596L<overload/Copy Constructor>.
e7ea3e70 1597
4aaa4757
FC
1598=item &CORE::%s cannot be called directly
1599
1600(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1601with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1602in this package cannot yet be called that way, but must be
1603called as barewords. Something like this will work:
1604
1605 BEGIN { *shove = \&CORE::push; }
1606 shove @array, 1,2,3; # pushes on to @array
1607
6798c92b
GS
1608=item CORE::%s is not a keyword
1609
1610(F) The CORE:: namespace is reserved for Perl keywords.
1611
675fa9ff
FC
1612=item Corrupted regexp opcode %d > %d
1613
1614(P) This is either an error in Perl, or, if you're using
1615one, your L<custom regular expression engine|perlreapi>. If not the
1616latter, report the problem through the L<perlbug> utility.
1617
a0d0e21e
LW
1618=item corrupted regexp pointers
1619
1620(P) The regular expression engine got confused by what the regular
1621expression compiler gave it.
1622
1623=item corrupted regexp program
1624
be771a83
GS
1625(P) The regular expression engine got passed a regexp program without a
1626valid magic number.
a0d0e21e 1627
de42a5a9 1628=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1629
1630(P) The malloc package that comes with Perl had an internal failure.
1631
49704364
LW
1632=item Count after length/code in unpack
1633
1634(F) You had an unpack template indicating a counted-length string, but
1635you have also specified an explicit size for the string. See
1636L<perlfunc/pack>.
1637
f2cccb4c
KW
1638=for comment
1639The following are used in lib/diagnostics.t for testing two =items that
1640share the same description. Changes here need to be propagated to there
1641
6651ba0b
FC
1642=item Deep recursion on anonymous subroutine
1643
a0d0e21e
LW
1644=item Deep recursion on subroutine "%s"
1645
be771a83
GS
1646(W recursion) This subroutine has called itself (directly or indirectly)
1647100 times more than it has returned. This probably indicates an
1648infinite recursion, unless you're writing strange benchmark programs, in
1649which case it indicates something else.
a0d0e21e 1650
aad1d01f
NC
1651This threshold can be changed from 100, by recompiling the F<perl> binary,
1652setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1653
e0e4a6e3
FC
1654=item (?(DEFINE)....) does not allow branches in regex; marked by
1655S<<-- HERE> in m/%s/
bcb95744 1656
6903afa2 1657(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1658most likely cause of this error is that you left out a parenthesis inside
1659of the C<....> part.
1660
9e3ec65c 1661The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1662discovered.
1663
62658f4d
PM
1664=item %s defines neither package nor VERSION--version check failed
1665
1666(F) You said something like "use Module 42" but in the Module file
1667there are neither package declarations nor a C<$VERSION>.
1668
36447869
FC
1669=item delete argument is index/value array slice, use array slice
1670
1671(F) You used index/value array slice syntax (C<%array[...]>) as
1672the argument to C<delete>. You probably meant C<@array[...]> with
1673an @ symbol instead.
1674
1675=item delete argument is key/value hash slice, use hash slice
1676
1677(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1678C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1679
0ffcbc25
FC
1680=item delete argument is not a HASH or ARRAY element or slice
1681
4a0af295 1682(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1683such as:
1684
1685 $foo{$bar}
1686 $ref->{"susie"}[12]
1687
1688or a hash or array slice, such as:
1689
1690 @foo[$bar, $baz, $xyzzy]
1691 @{$ref->[12]}{"susie", "queue"}
1692
fc36a67e
PP
1693=item Delimiter for here document is too long
1694
be771a83
GS
1695(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1696long for Perl to handle. You have to be seriously twisted to write code
1697that triggers this error.
fc36a67e 1698
6d3b25aa
RGS
1699=item Deprecated use of my() in false conditional
1700
fa816bf3
FC
1701(D deprecated) You used a declaration similar to C<my $x if 0>. There
1702has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1703not to be cleared at scope exit when its declaration includes a false
6903afa2 1704conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1705static variable. Since we intend to fix this bug, we don't want people
6903afa2 1706relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1707declaring the variable in a separate block outside the function, eg
36fb85f3 1708
6d3b25aa
RGS
1709 sub f { my $x if 0; return $x++ }
1710
1711becomes
1712
1713 { my $x; sub f { return $x++ } }
1714
ea9d9ebc 1715Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1716lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1717
1718 sub f { state $x; return $x++ }
1719
500ab966
RGS
1720=item DESTROY created new reference to dead object '%s'
1721
1722(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1723just being DESTROYed. Perl is confused, and prefers to abort rather
1724than to create a dangling reference.
500ab966 1725
3cdd684c
TP
1726=item Did not produce a valid header
1727
1728See Server error.
1729
6df41af2
GS
1730=item %s did not return a true value
1731
1732(F) A required (or used) file must return a true value to indicate that
1733it compiled correctly and ran its initialization code correctly. It's
1734traditional to end such a file with a "1;", though any true value would
1735do. See L<perlfunc/require>.
1736
cc507455 1737=item (Did you mean &%s instead?)
4633a7c4 1738
413ff9f6
FC
1739(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1740some such.
4633a7c4 1741
cc507455 1742=item (Did you mean "local" instead of "our"?)
33633739 1743
be771a83
GS
1744(W misc) Remember that "our" does not localize the declared global
1745variable. You have declared it again in the same lexical scope, which
1746seems superfluous.
33633739 1747
cc507455 1748=item (Did you mean $ or @ instead of %?)
a0d0e21e 1749
be771a83
GS
1750(W) You probably said %hash{$key} when you meant $hash{$key} or
1751@hash{@keys}. On the other hand, maybe you just meant %hash and got
1752carried away.
748a9306 1753
7e1af8bc 1754=item Died
5f05dabc
PP
1755
1756(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1757you called it with no args and C<$@> was empty.
5f05dabc 1758
3cdd684c
TP
1759=item Document contains no data
1760
1761See Server error.
1762
62658f4d
PM
1763=item %s does not define %s::VERSION--version check failed
1764
1765(F) You said something like "use Module 42" but the Module did not
943fc58e 1766define a C<$VERSION>.
62658f4d 1767
49704364
LW
1768=item '/' does not take a repeat count
1769
1770(F) You cannot put a repeat count of any kind right after the '/' code.
1771See L<perlfunc/pack>.
1772
95cb0d72
FC
1773=item Don't know how to get file name
1774
1775(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1776somehow called on another platform. This should not happen.
1777
4021c788 1778=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1779
1780(P) The internal handling of magical variables has been cursed.
1781
1782=item do_study: out of memory
1783
1784(P) This should have been caught by safemalloc() instead.
1785
6df41af2
GS
1786=item (Do you need to predeclare %s?)
1787
56da5a46
RGS
1788(S syntax) This is an educated guess made in conjunction with the message
1789"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1790name is being referenced that hasn't been declared yet. This may be
1791because of ordering problems in your file, or because of a missing
be771a83
GS
1792"sub", "package", "require", or "use" statement. If you're referencing
1793something that isn't defined yet, you don't actually have to define the
1794subroutine or package before the current location. You can use an empty
1795"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1796
ac206dc8
RGS
1797=item dump() better written as CORE::dump()
1798
1799(W misc) You used the obsolescent C<dump()> built-in function, without fully
1800qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1801
84d78eb7
YO
1802=item dump is not supported
1803
1804(F) Your machine doesn't support dump/undump.
1805
a0d0e21e
LW
1806=item Duplicate free() ignored
1807
be771a83
GS
1808(S malloc) An internal routine called free() on something that had
1809already been freed.
a0d0e21e 1810
1109a392
MHM
1811=item Duplicate modifier '%c' after '%c' in %s
1812
35f0cd76
FC
1813(W unpack) You have applied the same modifier more than once after a
1814type in a pack template. See L<perlfunc/pack>.
1109a392 1815
0953b66b
FC
1816=item each on reference is experimental
1817
0773cb3e
FC
1818(S experimental::autoderef) C<each> with a scalar argument is experimental
1819and may change or be removed in a future Perl version. If you want to
1820take the risk of using this feature, simply disable this warning:
0953b66b 1821
d401967c 1822 no warnings "experimental::autoderef";
0953b66b 1823
4633a7c4
LW
1824=item elseif should be elsif
1825
fa816bf3
FC
1826(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1827it's ugly. Your code will be interpreted as an attempt to call a method
1828named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1829unlikely to be what you want.
1830
e0e4a6e3 1831=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1832
af6f566e 1833(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1834described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1835a regular expression without specifying the property name.
ab13f0c7 1836
85ab1d1d 1837=item entering effective %s failed
5ff3f7a4 1838
85ab1d1d 1839(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1840effective uids or gids failed.
1841
c038024b
RGS
1842=item %ENV is aliased to %s
1843
1844(F) You're running under taint mode, and the C<%ENV> variable has been
1845aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1846program's environment. This is potentially insecure.
c038024b 1847
748a9306
LW
1848=item Error converting file specification %s
1849
5f05dabc 1850(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1851specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1852single form when it must operate on them directly. Either you've passed
1853an invalid file specification to Perl, or you've found a case the
1854conversion routines don't handle. Drat.
748a9306 1855
ad19ef22 1856=item Eval-group in insecure regular expression
e4d48cc9 1857
be771a83
GS
1858(F) Perl detected tainted data when trying to compile a regular
1859expression that contains the C<(?{ ... })> zero-width assertion, which
1860is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1861
ad19ef22 1862=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1863
be771a83
GS
1864(F) Perl tried to compile a regular expression containing the
1865C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1866pattern contains interpolated values. Since that is a security risk,
1867it is not allowed. If you insist, you may still do this by using the
1868C<re 'eval'> pragma or by explicitly building the pattern from an
1869interpolated string at run time and using that in an eval(). See
1870L<perlre/(?{ code })>.
e4d48cc9 1871
ad19ef22 1872=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1873
be771a83
GS
1874(F) A regular expression contained the C<(?{ ... })> zero-width
1875assertion, but that construct is only allowed when the C<use re 'eval'>
1876pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1877
e0e4a6e3
FC
1878=item EVAL without pos change exceeded limit in regex; marked by
1879S<<-- HERE> in m/%s/
1a147d38
YO
1880
1881(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1882any text. Restructure the pattern so that text is consumed.
1a147d38 1883
9e3ec65c 1884The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1885discovered.
1886
fc36a67e
PP
1887=item Excessively long <> operator
1888
1889(F) The contents of a <> operator may not exceed the maximum size of a
1890Perl identifier. If you're just trying to glob a long list of
1891filenames, try using the glob() operator, or put the filenames into a
1892variable and glob that.
1893
ed9aa3b7
SG
1894=item exec? I'm not *that* kind of operating system
1895
af8bb25a 1896(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1897OS. See L<perlport>.
ed9aa3b7 1898
fe13d51d 1899=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1900
1901(F) The final summary message when a Perl compilation fails.
1902
0ffcbc25
FC
1903=item exists argument is not a HASH or ARRAY element or a subroutine
1904
4a0af295 1905(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1906subroutine with an ampersand, such as:
1907
1908 $foo{$bar}
1909 $ref->{"susie"}[12]
1910 &do_something
1911
1912=item exists argument is not a subroutine name
1913
ccfc2567
FC
1914(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1915and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1916
a0d0e21e
LW
1917=item Exiting eval via %s
1918
be771a83
GS
1919(W exiting) You are exiting an eval by unconventional means, such as a
1920goto, or a loop control statement.
e476b1b5
GS
1921
1922=item Exiting format via %s
1923
9a2ff54b 1924(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1925goto, or a loop control statement.
a0d0e21e 1926
0a753a76
PP
1927=item Exiting pseudo-block via %s
1928
be771a83
GS
1929(W exiting) You are exiting a rather special block construct (like a
1930sort block or subroutine) by unconventional means, such as a goto, or a
1931loop control statement. See L<perlfunc/sort>.
0a753a76 1932
a0d0e21e
LW
1933=item Exiting subroutine via %s
1934
be771a83
GS
1935(W exiting) You are exiting a subroutine by unconventional means, such
1936as a goto, or a loop control statement.
a0d0e21e
LW
1937
1938=item Exiting substitution via %s
1939
be771a83
GS
1940(W exiting) You are exiting a substitution by unconventional means, such
1941as a return, a goto, or a loop control statement.
a0d0e21e 1942
e0e4a6e3 1943=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1944
675fa9ff 1945(F) You wrote something like
c608e803
KW
1946
1947 (?13
1948
1949to denote a capturing group of the form
1950L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1951but omitted the C<")">.
1952
e0e4a6e3 1953=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1954
8b6fbf55
FC
1955(F) The C<(?[...])> extended character class regular expression construct
1956only allows character classes (including character class escapes like
1957C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1958containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1959This allows a regular expression containing just C<(?[...])> to be
1960interpolated. If you see this error message, then you probably
1961have some other C<(?...)> construct inside your character class. See
1962L<perlrecharclass/Extended Bracketed Character Classes>.
1963
1f8155a2
FC
1964=item Experimental lvalue references not enabled
1965
1966(F) To use lvalue references, you must first enable them:
1967
1968 no warnings "experimental::lvalue_refs";
1969 use feature "lvalue_refs";
1970 \$x = \$y;
1971
30d9c59b
Z
1972=item Experimental subroutine signatures not enabled
1973
1974(F) To use subroutine signatures, you must first enable them:
1975
caa35032 1976 no warnings "experimental::signatures";
30d9c59b
Z
1977 use feature "signatures";
1978 sub foo ($left, $right) { ... }
1979
6da34ecb
FC
1980=item Experimental "%s" subs not enabled
1981
1982(F) To use lexical subs, you must first enable them:
1983
1984 no warnings 'experimental::lexical_subs';
1985 use feature 'lexical_subs';
1986 my sub foo { ... }
1987
7b8d334a
GS
1988=item Explicit blessing to '' (assuming package main)
1989
be771a83
GS
1990(W misc) You are blessing a reference to a zero length string. This has
1991the effect of blessing the reference into the package main. This is
1992usually not what you want. Consider providing a default target package,
1993e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1994
6df41af2
GS
1995=item %s: Expression syntax
1996
be771a83
GS
1997(A) You've accidentally run your script through B<csh> instead of Perl.
1998Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1999
2000=item %s failed--call queue aborted
2001
3c10abe3
AG
2002(F) An untrapped exception was raised while executing a UNITCHECK,
2003CHECK, INIT, or END subroutine. Processing of the remainder of the
2004queue of such routines has been prematurely ended.
6df41af2 2005
e0e4a6e3 2006=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2007
98d31c73 2008(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2009character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2010in your false range is interpreted as a literal "-". In a C<(?[...])>
2011construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2012the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2013the problem was discovered. See L<perlre>.
73b437c8 2014
1b1ee2ef 2015=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2016
be771a83
GS
2017(P) An error peculiar to VMS. Something untoward happened in a VMS
2018system service or RTL routine; Perl's exit status should provide more
2019details. The filename in "at %s" and the line number in "line %d" tell
2020you which section of the Perl source code is distressed.
a0d0e21e
LW
2021
2022=item fcntl is not implemented
2023
2024(F) Your machine apparently doesn't implement fcntl(). What is this, a
2025PDP-11 or something?
2026
22846ab4
AB
2027=item FETCHSIZE returned a negative value
2028
2029(F) A tied array claimed to have a negative number of elements, which
2030is not possible.
2031
f337b084
TH
2032=item Field too wide in 'u' format in pack
2033
d8b5cc61 2034(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2035which can't encode values above 63. So there is no point in asking for
2036a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2037C<u63> as the format.
f337b084 2038
af8c498a 2039=item Filehandle %s opened only for input
a0d0e21e 2040
6c8d78fb
HS
2041(W io) You tried to write on a read-only filehandle. If you intended
2042it to be a read-write filehandle, you needed to open it with "+<" or
2043"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2044write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2045
af8c498a 2046=item Filehandle %s opened only for output
a0d0e21e 2047
6c8d78fb
HS
2048(W io) You tried to read from a filehandle opened only for writing, If
2049you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2050with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2051read from the file, use "<". See L<perlfunc/open>. Another possibility
2052is that you attempted to open filedescriptor 0 (also known as STDIN) for
2053output (maybe you closed STDIN earlier?).
97828cef
RGS
2054
2055=item Filehandle %s reopened as %s only for input
2056
2057(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2058as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2059previously.
2060
2061=item Filehandle STDIN reopened as %s only for output
2062
2063(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2064as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2065
2066=item Final $ should be \$ or $name
2067
2068(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2069a literal dollar sign, or was meant to introduce a variable name that
2070happens to be missing. So you have to put either the backslash or the
2071name.
a0d0e21e 2072
56e90b21
GS
2073=item flock() on closed filehandle %s
2074
be771a83 2075(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2076some time before now. Check your control flow. flock() operates on
be771a83
GS
2077filehandles. Are you attempting to call flock() on a dirhandle by the
2078same name?
56e90b21 2079
6df41af2
GS
2080=item Format not terminated
2081
2082(F) A format must be terminated by a line with a solitary dot. Perl got
2083to the end of your file without finding such a line.
2084
a0d0e21e
LW
2085=item Format %s redefined
2086
e476b1b5 2087(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2088
2089 {
271595cc 2090 no warnings 'redefine';
a0d0e21e
LW
2091 eval "format NAME =...";
2092 }
2093
a0d0e21e
LW
2094=item Found = in conditional, should be ==
2095
e476b1b5 2096(W syntax) You said
a0d0e21e
LW
2097
2098 if ($foo = 123)
2099
2100when you meant
2101
2102 if ($foo == 123)
2103
2104(or something like that).
2105
6df41af2
GS
2106=item %s found where operator expected
2107
56da5a46
RGS
2108(S syntax) The Perl lexer knows whether to expect a term or an operator.
2109If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2110operator, it gives you this warning. Usually it indicates that an
2111operator or delimiter was omitted, such as a semicolon.
6df41af2 2112
a0d0e21e
LW
2113=item gdbm store returned %d, errno %d, key "%s"
2114
2115(S) A warning from the GDBM_File extension that a store failed.
2116
2117=item gethostent not implemented
2118
2119(F) Your C library apparently doesn't implement gethostent(), probably
2120because if it did, it'd feel morally obligated to return every hostname
2121on the Internet.
2122
69282e91 2123=item get%sname() on closed socket %s
a0d0e21e 2124
be771a83
GS
2125(W closed) You tried to get a socket or peer socket name on a closed
2126socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2127
748a9306
LW
2128=item getpwnam returned invalid UIC %#o for user "%s"
2129
2130(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2131C<getpwnam> operator returned an invalid UIC.
2132
6df41af2
GS
2133=item getsockopt() on closed socket %s
2134
be771a83
GS
2135(W closed) You tried to get a socket option on a closed socket. Did you
2136forget to check the return value of your socket() call? See
6df41af2
GS
2137L<perlfunc/getsockopt>.
2138
0f539b13
BF
2139=item given is experimental
2140
675fa9ff
FC
2141(S experimental::smartmatch) C<given> depends on smartmatch, which
2142is experimental, so its behavior may change or even be removed
2143in any future release of perl. See the explanation under
2144L<perlsyn/Experimental Details on given and when>.
0f539b13 2145
68567d27
FC
2146=item Global symbol "%s" requires explicit package name (did you forget to
2147declare "my %s"?)
6df41af2 2148
a4edf47d 2149(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2150that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2151declared beforehand using "our", or explicitly qualified to say
2152which package the global variable is in (using "::").
6df41af2 2153
e476b1b5
GS
2154=item glob failed (%s)
2155
5ead438e 2156(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2157for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2158pattern that caused the external program to fail and exit with a
be771a83 2159nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2160resulted in a coredump, this may also mean that your csh (C shell)
2161is broken. If so, you should change all of the csh-related variables
2162in config.sh: If you have tcsh, make the variables refer to it as
2163if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2164all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2165think csh is missing. In either case, after editing config.sh, run
75b44862 2166C<./Configure -S> and rebuild Perl.
e476b1b5 2167
a0d0e21e
LW
2168=item Glob not terminated
2169
2170(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2171a term, so it's looking for the corresponding right angle bracket, and
2172not finding it. Chances are you left some needed parentheses out
2173earlier in the line, and you really meant a "less than".
a0d0e21e 2174
b35b96b6
JH
2175=item gmtime(%f) failed
2176
2177(W overflow) You called C<gmtime> with a number that it could not handle:
2178too large, too small, or NaN. The returned value is C<undef>.
2179
bcd05b94 2180=item gmtime(%f) too large
8b56d6ff 2181
e9200be3 2182(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2183it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2184date. This warning is also triggered with NaN (the special
fc003d4b
MS
2185not-a-number value).
2186
bcd05b94 2187=item gmtime(%f) too small
fc003d4b 2188
e9200be3 2189(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2190it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2191
6df41af2 2192=item Got an error from DosAllocMem
a0d0e21e 2193
6df41af2
GS
2194(P) An error peculiar to OS/2. Most probably you're using an obsolete
2195version of Perl, and this should not happen anyway.
a0d0e21e
LW
2196
2197=item goto must have label
2198
2199(F) Unlike with "next" or "last", you're not allowed to goto an
2200unspecified destination. See L<perlfunc/goto>.
2201
6651ba0b
FC
2202=item Goto undefined subroutine%s
2203
2204(F) You tried to call a subroutine with C<goto &sub> syntax, but
2205the indicated subroutine hasn't been defined, or if it was, it
2206has since been undefined.
2207
6fbc9859 2208=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2209S<<-- HERE> in m/%s/
1f4f6bf1
YO
2210
2211(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2212they must start with a non-digit word character. A common cause of
2213this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2214
5a25739d
FC
2215=item ()-group starts with a count
2216
2217(F) A ()-group started with a count. A count is supposed to follow
2218something: a template character or a ()-group. See L<perlfunc/pack>.
2219
fe13d51d 2220=item %s had compilation errors.
6df41af2
GS
2221
2222(F) The final summary message when a C<perl -c> fails.
2223
a0d0e21e
LW
2224=item Had to create %s unexpectedly
2225
be771a83
GS
2226(S internal) A routine asked for a symbol from a symbol table that ought
2227to have existed already, but for some reason it didn't, and had to be
2228created on an emergency basis to prevent a core dump.
a0d0e21e 2229
6df41af2
GS
2230=item %s has too many errors
2231
2232(F) The parser has given up trying to parse the program after 10 errors.
2233Further error messages would likely be uninformative.
2234
cc4d09e1
KW
2235=item Having more than one /%c regexp modifier is deprecated
2236
2237(D deprecated, regexp) You used the indicated regular expression pattern
2238modifier at least twice in a string of modifiers. It is deprecated to
2239do this with this particular modifier, to allow future extensions to the
2240Perl language.
2241
61e61fbc
JH
2242=item Hexadecimal float: exponent overflow
2243
d8f2b442 2244(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2245than the floating point supports.
2246
2247=item Hexadecimal float: exponent underflow
2248
d8f2b442 2249(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2250than the floating point supports.
2251
cf4f6003
JH
2252=item Hexadecimal float: internal error
2253
2254(F) Something went horribly bad in hexadecimal float handling.
2255
61e61fbc
JH
2256=item Hexadecimal float: mantissa overflow
2257
2258(W overflow) The hexadecimal floating point literal had more bits in
2259the mantissa (the part between the 0x and the exponent, also known as
2260the fraction or the significand) than the floating point supports.
2261
40bca5ae
JH
2262=item Hexadecimal float: precision loss
2263
2264(W overflow) The hexadecimal floating point had internally more
2265digits than could be output. This can be caused by unsupported
2266long double formats, or by 64-bit integers not being available
2267(needed to retrieve the digits under some configurations).
2268
2269=item Hexadecimal float: unsupported long double format
2270
2271(F) You have configured Perl to use long doubles but
d8f2b442 2272the internals of the long double format are unknown;
40bca5ae
JH
2273therefore the hexadecimal float output is impossible.
2274
252aa082
JH
2275=item Hexadecimal number > 0xffffffff non-portable
2276
e476b1b5 2277(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2278(4294967295) and therefore non-portable between systems. See
2279L<perlport> for more on portability concerns.
252aa082 2280
8903cb82
PP
2281=item Identifier too long
2282
2283(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2284about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2285names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2286of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2287
e0e4a6e3
FC
2288=item Ignoring zero length \N{} in character class in regex; marked by
2289S<<-- HERE> in m/%s/
fc8cd66c 2290
f3ba6905 2291(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2292zero-length sequence. When such an escape is used in a character class
2293its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2294been used, and the correct charname handler is in scope.
2295
6df41af2 2296=item Illegal binary digit %s
f675dbe5 2297
6df41af2 2298(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2299
6df41af2 2300=item Illegal binary digit %s ignored
a0d0e21e 2301
be771a83
GS
2302(W digit) You may have tried to use a digit other than 0 or 1 in a
2303binary number. Interpretation of the binary number stopped before the
2304offending digit.
a0d0e21e 2305
6597eb22
FC
2306=item Illegal character after '_' in prototype for %s : %s
2307
e4d150f1
FC
2308(W illegalproto) An illegal character was found in a prototype
2309declaration. The '_' in a prototype must be followed by a ';',
2310indicating the rest of the parameters are optional, or one of '@'
2311or '%', since those two will accept 0 or more final parameters.
6597eb22 2312
78d0fecf 2313=item Illegal character \%o (carriage return)
4fdae800 2314
d5898338 2315(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2316would any other whitespace, which means you should never see this error
2317when Perl was built using standard options. For some reason, your
2318version of Perl appears to have been built without this support. Talk
2319to your Perl administrator.
4fdae800 2320
d37a9538
ST
2321=item Illegal character in prototype for %s : %s
2322
197afce1 2323(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2324Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2325Perhaps you were trying to write a subroutine signature but didn't enable
2326that feature first (C<use feature 'signatures'>), so your signature was
2327instead interpreted as a bad prototype.
d37a9538 2328
904d85c5
RGS
2329=item Illegal declaration of anonymous subroutine
2330
2331(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2332you must always specify a block of code. See L<perlsub>.
904d85c5 2333
8e742a20
MHM
2334=item Illegal declaration of subroutine %s
2335
6903afa2 2336(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2337
a0d0e21e
LW
2338=item Illegal division by zero
2339
be771a83
GS
2340(F) You tried to divide a number by 0. Either something was wrong in
2341your logic, or you need to put a conditional in to guard against
2342meaningless input.
a0d0e21e 2343
6df41af2
GS
2344=item Illegal hexadecimal digit %s ignored
2345
be771a83
GS
2346(W digit) You may have tried to use a character other than 0 - 9 or
2347A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2348number stopped before the illegal character.
6df41af2 2349
a0d0e21e
LW
2350=item Illegal modulus zero
2351
be771a83
GS
2352(F) You tried to divide a number by 0 to get the remainder. Most
2353numbers don't take to this kindly.
a0d0e21e 2354
6df41af2 2355=item Illegal number of bits in vec
399388f4 2356
6df41af2
GS
2357(F) The number of bits in vec() (the third argument) must be a power of
2358two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2359
2360=item Illegal octal digit %s
a0d0e21e 2361
d1be9408 2362(F) You used an 8 or 9 in an octal number.
a0d0e21e 2363
399388f4 2364=item Illegal octal digit %s ignored
748a9306 2365
d1be9408 2366(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2367Interpretation of the octal number stopped before the 8 or 9.
748a9306 2368
e0e4a6e3 2369=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2370
675fa9ff 2371(F) You wrote something like
c608e803
KW
2372
2373 (?+foo)
2374
2375The C<"+"> is valid only when followed by digits, indicating a
2376capturing group. See
2377L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2378
375ed12a
JH
2379=item Illegal suidscript
2380
2381(F) The script run under suidperl was somehow illegal.
2382
fe13d51d 2383=item Illegal switch in PERL5OPT: -%c
6ff81951 2384
6df41af2 2385(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2386following switches: B<-[CDIMUdmtw]>.
6ff81951 2387
6df41af2 2388=item Ill-formed CRTL environ value "%s"
81e118e0 2389
75b44862 2390(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2391internal environ array, and encountered an element without the C<=>
2392delimiter used to separate keys from values. The element is ignored.
09bef843 2393
6df41af2 2394=item Ill-formed message in prime_env_iter: |%s|
54310121 2395
be771a83
GS
2396(W internal) A warning peculiar to VMS. Perl tried to read a logical
2397name or CLI symbol definition when preparing to iterate over %ENV, and
2398didn't see the expected delimiter between key and value, so the line was
2399ignored.
54310121 2400
6df41af2 2401=item (in cleanup) %s
9607fc9c 2402
be771a83
GS
2403(W misc) This prefix usually indicates that a DESTROY() method raised
2404the indicated exception. Since destructors are usually called by the
2405system at arbitrary points during execution, and often a vast number of
2406times, the warning is issued only once for any number of failures that
2407would otherwise result in the same message being repeated.
6df41af2 2408
be771a83
GS
2409Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2410also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2411
e0e4a6e3
FC
2412=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2413in m/%s/
0d0b4b3b 2414
675fa9ff 2415(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2416expression inside the construct was completely empty, or if there are
2417too many or few operands for the number of operators. Perl is not smart
2418enough to give you a more precise indication as to what is wrong.
2419
6fbc9859
MH
2420=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2421parent '%s'
2c7d6b9c
RGS
2422
2423(F) The method resolution order (MRO) of the given class is not
2424C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2425documentation in L<mro> for more information.
2426
979699d9
JH
2427=item In EBCDIC the v-string components cannot exceed 2147483647
2428
2429(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2430Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2431encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2432
6a2ed79a 2433=item Infinite recursion in regex
1a147d38
YO
2434
2435(F) You used a pattern that references itself without consuming any input
6903afa2 2436text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2437either consume text or fail.
2438
6dbe9451
NC
2439=item Initialization of state variables in list context currently forbidden
2440
6903afa2
FC
2441(F) Currently the implementation of "state" only permits the
2442initialization of scalar variables in scalar context. Re-write
2443C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2444context. Constructions such as C<state (@a) = foo()> will be
2445supported in a future perl release.
6dbe9451 2446
2186f873
FC
2447=item %%s[%s] in scalar context better written as $%s[%s]
2448
2449(W syntax) In scalar context, you've used an array index/value slice
2450(indicated by %) to select a single element of an array. Generally
2451it's better to ask for a scalar value (indicated by $). The difference
2452is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2453returns and when evaluating its argument, while C<%foo[&bar]> provides
2454a list context to its subscript, which can do weird things if you're
2455expecting only one subscript. When called in list context, it also
2456returns the index (what C<&bar> returns) in addition to the value.
2457
2458=item %%s{%s} in scalar context better written as $%s{%s}
2459
2460(W syntax) In scalar context, you've used a hash key/value slice
2461(indicated by %) to select a single element of a hash. Generally it's
2462better to ask for a scalar value (indicated by $). The difference
2463is that C<$foo{&bar}> always behaves like a scalar, both in the value
2464it returns and when evaluating its argument, while C<@foo{&bar}> and
2465provides a list context to its subscript, which can do weird things
2466if you're expecting only one subscript. When called in list context,
2467it also returns the key in addition to the value.
2468
a0d0e21e
LW
2469=item Insecure dependency in %s
2470
8b1a09fc 2471(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2472The tainting mechanism is turned on when you're running setuid or
2473setgid, or when you specify B<-T> to turn it on explicitly. The
2474tainting mechanism labels all data that's derived directly or indirectly
2475from the user, who is considered to be unworthy of your trust. If any
2476such data is used in a "dangerous" operation, you get this error. See
2477L<perlsec> for more information.
a0d0e21e
LW
2478
2479=item Insecure directory in %s
2480
be771a83
GS
2481(F) You can't use system(), exec(), or a piped open in a setuid or
2482setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2483the world. Also, the PATH must not contain any relative directory.
2484See L<perlsec>.
a0d0e21e 2485
62f468fc 2486=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2487
2488(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2489setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2490C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2491supplied (or potentially supplied) by the user. The script must set
2492the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2493
0e9be77f
DM
2494=item Insecure user-defined property %s
2495
2496(F) Perl detected tainted data when trying to compile a regular
2497expression that contains a call to a user-defined character property
2498function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2499See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2500
b9ef414d
FC
2501=item Integer overflow in format string for %s
2502
2503(F) The indexes and widths specified in the format string of C<printf()>
2504or C<sprintf()> are too large. The numbers must not overflow the size of
2505integers for your architecture.
2506
a7ae9550
GS
2507=item Integer overflow in %s number
2508
35928bc5 2509(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2510either as a literal or as an argument to hex() or oct() is too big for
2511your architecture, and has been converted to a floating point number.
2512On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2513representable without overflow is 0xFFFFFFFF, 037777777777, or
25140b11111111111111111111111111111111 respectively. Note that Perl
2515transparently promotes all numbers to a floating point representation
2516internally--subject to loss of precision errors in subsequent
2517operations.
bbce6d69 2518
fc89ca81
FC
2519=item Integer overflow in srand
2520
2521(S overflow) The number you have passed to srand is too big to fit
2522in your architecture's integer representation. The number has been
2523replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2524architectures). This means you may be getting less randomness than
2525you expect, because different random seeds above the maximum will
2526return the same sequence of random numbers.
2527
46314c13
JP
2528=item Integer overflow in version
2529
18da5252
FC
2530=item Integer overflow in version %d
2531
784d71ed
FC
2532(W overflow) Some portion of a version initialization is too large for
2533the size of integers for your architecture. This is not a warning
f084e84f 2534because there is no rational reason for a version to try and use an
784d71ed
FC
2535element larger than typically 2**32. This is usually caused by trying
2536to use some odd mathematical operation as a version, like 100/9.
46314c13 2537
e0e4a6e3 2538=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2539
2540(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2541The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2542discovered.
2543
748a9306
LW
2544=item Internal inconsistency in tracking vforks
2545
be771a83
GS
2546(S) A warning peculiar to VMS. Perl keeps track of the number of times
2547you've called C<fork> and C<exec>, to determine whether the current call
2548to C<exec> should affect the current script or a subprocess (see
2549L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2550Perl is making a guess and treating this C<exec> as a request to
2551terminate the Perl script and execute the specified command.
748a9306 2552
870978ae
FC
2553=item internal %<num>p might conflict with future printf extensions
2554
2555(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2556formatting follows a slightly different set of rules when called from
2557C or XS code. Specifically, formats consisting of digits followed
2558by "p" (e.g., "%7p") are reserved for future use. If you see this
2559message, then an XS module tried to call that routine with one such
2560reserved format.
2561
e0e4a6e3 2562=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2563
fa816bf3 2564(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2565S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2566discovered.
a0d0e21e 2567
6df41af2
GS
2568=item %s (...) interpreted as function
2569
75b44862 2570(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2571followed by parentheses turns into a function, with all the list
64977eb6 2572operators arguments found inside the parentheses. See
13a2d996 2573L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2574
f51551f7
FC
2575=item In '(?...)', the '(' and '?' must be adjacent in regex;
2576marked by S<<-- HERE> in m/%s/
2577
2578(F) The two-character sequence C<"(?"> in this context in a regular
2579expression pattern should be an indivisible token, with nothing
2580intervening between the C<"("> and the C<"?">, but you separated them
2581with whitespace.
2582
09bef843
SB
2583=item Invalid %s attribute: %s
2584
a4a4c9e2 2585(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2586by Perl or by a user-supplied handler. See L<attributes>.
2587
2588=item Invalid %s attributes: %s
2589
a4a4c9e2 2590(F) The indicated attributes for a subroutine or variable were not
be771a83 2591recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2592
e0e4a6e3
FC
2593=item Invalid character in charnames alias definition; marked by
2594S<<-- HERE> in '%s
225fb84f
KW
2595
2596(F) You tried to create a custom alias for a character name, with
2597the C<:alias> option to C<use charnames> and the specified character in
2598the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2599
c8028aa6
TC
2600=item Invalid \0 character in %s for %s: %s\0%s
2601
fa3234e3
FC
2602(W syscalls) Embedded \0 characters in pathnames or other system call
2603arguments produce a warning as of 5.20. The parts after the \0 were
2604formerly ignored by system calls.
c8028aa6 2605
e0e4a6e3 2606=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2607
2608(F) Only certain characters are valid for character names. The
2609indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2610
c635e13b
PP
2611=item Invalid conversion in %s: "%s"
2612
be771a83
GS
2613(W printf) Perl does not understand the given format conversion. See
2614L<perlfunc/sprintf>.
c635e13b 2615
e0e4a6e3
FC
2616=item Invalid escape in the specified encoding in regex; marked by
2617S<<-- HERE> in m/%s/
9e08bc66 2618
98d31c73 2619(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2620didn't correspond to a single character through the conversion
2621from the encoding specified by the encoding pragma.
98d31c73
FC
2622The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2623instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2624The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2625escape was discovered.
2626
8149aa9f
FC
2627=item Invalid hexadecimal number in \N{U+...}
2628
e0e4a6e3
FC
2629=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2630S<<-- HERE> in m/%s/
aec0ef10 2631
8149aa9f 2632(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2633number. Either it is empty, or you tried to use a character other than
26340 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2635
6651ba0b
FC
2636=item Invalid module name %s with -%c option: contains single ':'
2637
2638(F) The module argument to perl's B<-m> and B<-M> command-line options
2639cannot contain single colons in the module name, but only in the
2640arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2641B<-MFoo:Bar=baz> is not.
2642
2c7d6b9c
RGS
2643=item Invalid mro name: '%s'
2644
162a3e34
FC
2645(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2646where C<foo> is not a valid method resolution order (MRO). Currently,
2647the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2648a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2649
40e4140b
FC
2650=item Invalid negative number (%s) in chr
2651
2652(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2653not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2654character (U+FFFD).
2655
6651ba0b
FC
2656=item invalid option -D%c, use -D'' to see choices
2657
8ff21bfe
FC
2658(S debugging) Perl was called with invalid debugger flags. Call perl
2659with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2660See also L<perlrun/-Dletters>.
6651ba0b 2661
e0e4a6e3 2662=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2663
2664(F) The range specified in a character class had a minimum character
7253e4e3
RK
2665greater than the maximum character. One possibility is that you forgot the
2666C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2667up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2668problem was discovered. See L<perlre>.
6df41af2 2669
d1573ac7 2670=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2671
2672(F) The range specified in the tr/// or y/// operator had a minimum
2673character greater than the maximum character. See L<perlop>.
2674
09bef843
SB
2675=item Invalid separator character %s in attribute list
2676
0120eecf 2677(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2678elements of an attribute list. If the previous attribute had a
2679parenthesised parameter list, perhaps that list was terminated too soon.
2680See L<attributes>.
09bef843 2681
b4581f09
JH
2682=item Invalid separator character %s in PerlIO layer specification %s
2683
2bfc5f71
FC
2684(W layer) When pushing layers onto the Perl I/O system, something other
2685than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2686If the previous attribute had a parenthesised parameter list, perhaps that
2687list was terminated too soon.
2688
2c86d456
DG
2689=item Invalid strict version format (%s)
2690
fa816bf3 2691(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2692A "strict" version number is a positive decimal number (integer or
2693decimal-fraction) without exponentiation or else a dotted-decimal
2694v-string with a leading 'v' character and at least three components.
a6485a24 2695The parenthesized text indicates which criteria were not met.
2c86d456
DG
2696See the L<version> module for more details on allowed version formats.
2697
49704364 2698=item Invalid type '%s' in %s
96e4d5b1 2699
49704364
LW
2700(F) The given character is not a valid pack or unpack type.
2701See L<perlfunc/pack>.
6728c851 2702
49704364 2703(W) The given character is not a valid pack or unpack type but used to be
75b44862 2704silently ignored.
96e4d5b1 2705
2c86d456
DG
2706=item Invalid version format (%s)
2707
fa816bf3 2708(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2709A "lax" version number is a positive decimal number (integer or
2710decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2711v-string. If the v-string has fewer than three components, it
2712must have a leading 'v' character. Otherwise, the leading 'v' is
2713optional. Both decimal and dotted-decimal versions may have a
2714trailing "alpha" component separated by an underscore character
2715after a fractional or dotted-decimal component. The parenthesized
2716text indicates which criteria were not met. See the L<version> module
2717for more details on allowed version formats.
46314c13 2718
798ae1b7
DG
2719=item Invalid version object
2720
fa816bf3
FC
2721(F) The internal structure of the version object was invalid.
2722Perhaps the internals were modified directly in some way or
2723an arbitrary reference was blessed into the "version" class.
798ae1b7 2724
cd209d9d 2725=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2726marked by S<<-- HERE> in m/%s/
675fa9ff 2727
cd209d9d 2728(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2729this context in a regular expression pattern should be an
2730indivisible token, with nothing intervening between the C<"(">
cd209d9d 2731and the C<"*">, but you separated them.
675fa9ff 2732
a0d0e21e
LW
2733=item ioctl is not implemented
2734
2735(F) Your machine apparently doesn't implement ioctl(), which is pretty
2736strange for a machine that supports C.
2737
c289d2f7
JH
2738=item ioctl() on unopened %s
2739
2740(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2741Check your control flow and number of arguments.
c289d2f7 2742
fe13d51d 2743=item IO layers (like '%s') unavailable
363c40c4
SB
2744
2745(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2746you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2747with 'useperlio'.
2748
80cbd5ad
JH
2749=item IO::Socket::atmark not implemented on this architecture
2750
2751(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2752neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2753
4f650b80 2754=item $* is no longer supported
b4581f09 2755
4f650b80 2756(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2757perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2758previous versions of perl the use of C<$*> enabled or disabled multi-line
2759matching within a string.
4fd19576
B
2760
2761Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2762modifiers. You can enable C</m> for a lexical scope (even a whole file)
2763with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2764then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2765
8ae1fe26
RGS
2766=item $# is no longer supported
2767
a58ac25e 2768(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2769perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2770should use the printf/sprintf functions instead.
8ae1fe26 2771
ccf3535a 2772=item '%s' is not a code reference
6ad11d81 2773
6903afa2
FC
2774(W overload) The second (fourth, sixth, ...) argument of
2775overload::constant needs to be a code reference. Either
2776an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2777
ccf3535a 2778=item '%s' is not an overloadable type
6ad11d81 2779
04a80ee0
RGS
2780(W overload) You tried to overload a constant type the overload package is
2781unaware of.
6ad11d81 2782
5a25739d
FC
2783=item -i used with no filenames on the command line, reading from STDIN
2784
2785(S inplace) The C<-i> option was passed on the command line, indicating
2786that the script is intended to edit files in place, but no files were
2787given. This is usually a mistake, since editing STDIN in place doesn't
2788make sense, and can be confusing because it can make perl look like
2789it is hanging when it is really just trying to read from STDIN. You
2790should either pass a filename to edit, or remove C<-i> from the command
2791line. See L<perlrun> for more details.
2792
aec0ef10 2793=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2794
2795(P) The regular expression parser is confused.
2796
0953b66b
FC
2797=item keys on reference is experimental
2798
0773cb3e
FC
2799(S experimental::autoderef) C<keys> with a scalar argument is experimental
2800and may change or be removed in a future Perl version. If you want to
2801take the risk of using this feature, simply disable this warning:
0953b66b 2802
d401967c 2803 no warnings "experimental::autoderef";
0953b66b 2804
a0d0e21e
LW
2805=item Label not found for "last %s"
2806
be771a83
GS
2807(F) You named a loop to break out of, but you're not currently in a loop
2808of that name, not even if you count where you were called from. See
2809L<perlfunc/last>.
a0d0e21e
LW
2810
2811=item Label not found for "next %s"
2812
2813(F) You named a loop to continue, but you're not currently in a loop of
2814that name, not even if you count where you were called from. See
2815L<perlfunc/last>.
2816
2817=item Label not found for "redo %s"
2818
2819(F) You named a loop to restart, but you're not currently in a loop of
2820that name, not even if you count where you were called from. See
2821L<perlfunc/last>.
2822
85ab1d1d 2823=item leaving effective %s failed
5ff3f7a4 2824
85ab1d1d 2825(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2826effective uids or gids failed.
2827
49704364
LW
2828=item length/code after end of string in unpack
2829
d7f8936a 2830(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2831length/code combination tried to obtain more data. This results in
2832an undefined value for the length. See L<perlfunc/pack>.
49704364 2833
25e26107 2834=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2835
0d46a4e7
FC
2836(W syntax) You used length() on either an array or a hash when you
2837probably wanted a count of the items.
e508c8a4
MH
2838
2839Array size can be obtained by doing:
2840
2841 scalar(@array);
2842
2843The number of items in a hash can be obtained by doing:
2844
2845 scalar(keys %hash);
2846
f0e67a1d
Z
2847=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2848
d4fe7078
RS
2849(F) An extension is attempting to insert text into the current parse
2850(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2851couldn't be part of the current input. This is an inherent pitfall
2852of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2853it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2854
2855=item Lexing code internal error (%s)
2856
2857(F) Lexing code supplied by an extension violated the lexer's API in a
2858detectable way.
2859
69282e91 2860=item listen() on closed socket %s
a0d0e21e 2861
be771a83
GS
2862(W closed) You tried to do a listen on a closed socket. Did you forget
2863to check the return value of your socket() call? See
2864L<perlfunc/listen>.
a0d0e21e 2865
6651ba0b
FC
2866=item List form of piped open not implemented
2867
2868(F) On some platforms, notably Windows, the three-or-more-arguments
2869form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2870Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2871
b35b96b6
JH
2872=item localtime(%f) failed
2873
2874(W overflow) You called C<localtime> with a number that it could not handle:
2875too large, too small, or NaN. The returned value is C<undef>.
2876
bcd05b94 2877=item localtime(%f) too large
8b56d6ff 2878
e9200be3 2879(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2880than it can reliably handle and C<localtime> probably returned the
6903afa2 2881wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2882not-a-number value).
2883
bcd05b94 2884=item localtime(%f) too small
fc003d4b 2885
e9200be3 2886(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2887than it can reliably handle and C<localtime> probably returned the
e7a1a147 2888wrong date.
8b56d6ff 2889
58e23c8d 2890=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2891
2892(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2893handle. This restriction may be eased in a future release.
2e50fd82 2894
b88df990
NC
2895=item Lost precision when %s %f by 1
2896
e63e8a91
FC
2897(W imprecision) The value you attempted to increment or decrement by one
2898is too large for the underlying floating point representation to store
2899accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2900warning because it has already switched from integers to floating point
2901when values are too large for integers, and now even floating point is
2902insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2903
93fad930 2904=item lstat() on filehandle%s
2f7da168
RK
2905
2906(W io) You tried to do an lstat on a filehandle. What did you mean
2907by that? lstat() makes sense only on filenames. (Perl did a fstat()
2908instead on the filehandle.)
2909
345d70e3 2910=item lvalue attribute %s already-defined subroutine
bb3abb05 2911
345d70e3
FC
2912(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2913attribute on or off on a Perl subroutine that is already defined
2914does not always work properly. It may or may not do what you
2915want, depending on what code is inside the subroutine, with exact
2916details subject to change between Perl versions. Only do this
2917if you really know what you are doing.
bb3abb05 2918
885ef6f5
GG
2919=item lvalue attribute ignored after the subroutine has been defined
2920
345d70e3
FC
2921(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2922subroutine an lvalue subroutine after it has been defined is
2923not permitted. To make the subroutine an lvalue subroutine,
2924add the lvalue attribute to the definition, or put the C<sub
2925foo :lvalue;> declaration before the definition.
2926
2927See also L<attributes.pm|attributes>.
885ef6f5 2928
1f8155a2
FC
2929=item Lvalue references are experimental
2930
2931(S experimental::lvalue_refs) This warning is emitted if you use
2932a reference constructor on the left-hand side of an assignment to
2933alias one variable to another. Simply suppress the warning if you
2934want to use the feature, but know that in doing so you are taking
2935the risk of using an experimental feature which may change or be
2936removed in a future Perl version:
2937
2938 no warnings "experimental::lvalue_refs";
2939 use feature "lvalue_refs";
2940 \$x = \$y;
2941
6f1b3ab0
FC
2942=item Magical list constants are not supported
2943
2944(F) You assigned a magical array to a stash element, and then tried
2945to use the subroutine from the same slot. You are asking Perl to do
2946something it cannot do, details subject to change between Perl versions.
2947
2db62bbc 2948=item Malformed integer in [] in pack
49704364 2949
2db62bbc 2950(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2951are permitted. See L<perlfunc/pack>.
2952
2953=item Malformed integer in [] in unpack
2954
2db62bbc 2955(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2956are permitted. See L<perlfunc/pack>.
2957
6df41af2
GS
2958=item Malformed PERLLIB_PREFIX
2959
2960(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2961
2962 prefix1;prefix2
2963
2964or
6df41af2
GS
2965 prefix1 prefix2
2966
be771a83
GS
2967with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2968a builtin library search path, prefix2 is substituted. The error may
2969appear if components are not found, or are too long. See
fecfaeb8 2970"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2971
2f758a16
ST
2972=item Malformed prototype for %s: %s
2973
d37a9538
ST
2974(F) You tried to use a function with a malformed prototype. The
2975syntax of function prototypes is given a brief compile-time check for
2976obvious errors like invalid characters. A more rigorous check is run
2977when the function is called.
30d9c59b
Z
2978Perhaps the function's author was trying to write a subroutine signature
2979but didn't enable that feature first (C<use feature 'signatures'>),
2980so the signature was instead interpreted as a bad prototype.
2f758a16 2981
ba210ebe
JH
2982=item Malformed UTF-8 character (%s)
2983
4d6f11e5 2984(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2985encoding rules, even though it had the UTF8 flag on.
ba210ebe 2986
2575c402
JW
2987One possible cause is that you set the UTF8 flag yourself for data that
2988you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 29898-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2990
2991If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2992sequences are handled gracefully, but if you use C<:utf8>, the flag is
2993set without validating the data, possibly resulting in this error
2994message.
2995
2996See also L<Encode/"Handling Malformed Data">.
901b21bf 2997
107160e2
KW
2998=item Malformed UTF-8 character immediately after '%s'
2999
3000(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3001encoding rules. The message prints out the properly encoded characters
3002just before the first bad one. If C<utf8> warnings are enabled, a
3003warning is generated that gives more details about the type of
3004malformation.
3005
bde9e88d 3006=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3007
3008(F) The charnames handler returned malformed UTF-8.
3009
4a5d3a93
FC
3010=item Malformed UTF-8 string in '%c' format in unpack
3011
3012(F) You tried to unpack something that didn't comply with UTF-8 encoding
3013rules and perl was unable to guess how to make more progress.
3014
f337b084
TH
3015=item Malformed UTF-8 string in pack
3016
3017(F) You tried to pack something that didn't comply with UTF-8 encoding
3018rules and perl was unable to guess how to make more progress.
3019
3020=item Malformed UTF-8 string in unpack
3021
3022(F) You tried to unpack something that didn't comply with UTF-8 encoding
3023rules and perl was unable to guess how to make more progress.
3024
4a5d3a93 3025=item Malformed UTF-16 surrogate
f337b084 3026
4a5d3a93
FC
3027(F) Perl thought it was reading UTF-16 encoded character data but while
3028doing it Perl met a malformed Unicode surrogate.
3029
30d9c59b
Z
3030=item Mandatory parameter follows optional parameter
3031
3032(F) In a subroutine signature, you wrote something like "$a = undef,
3033$b", making an earlier parameter optional and a later one mandatory.
3034Parameters are filled from left to right, so it's impossible for the
3035caller to omit an earlier one and pass a later one. If you want to act
3036as if the parameters are filled from right to left, declare the rightmost
3037optional and then shuffle the parameters around in the subroutine's body.
3038
2d88a86a
KW
3039=item Matched non-Unicode code point 0x%X against Unicode property; may
3040not be portable
3041
3042(S non_unicode) Perl allows strings to contain a superset of
3043Unicode code points; each code point may be as large as what is storable
3044in an unsigned integer on your system, but these may not be accepted by
3045other languages/systems. This message occurs when you matched a string
3046containing such a code point against a regular expression pattern, and
3047the code point was matched against a Unicode property, C<\p{...}> or
3048C<\P{...}>. Unicode properties are only defined on Unicode code points,
3049so the result of this match is undefined by Unicode, but Perl (starting
3050in v5.20) treats non-Unicode code points as if they were typical
3051unassigned Unicode ones, and matched this one accordingly. Whether a
3052given property matches these code points or not is specified in
3053L<perluniprops/Properties accessible through \p{} and \P{}>.
3054
3055This message is suppressed (unless it has been made fatal) if it is
3056immaterial to the results of the match if the code point is Unicode or
3057not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3058the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3059Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3060every code point except these 22.)
3061
3062Getting this message indicates that the outcome of the match arguably
3063should have been the opposite of what actually happened. If you think
3064that is the case, you may wish to make the C<non_unicode> warnings
3065category fatal; if you agree with Perl's decision, you may wish to turn
3066off this category.
3067
3068See L<perlunicode/Beyond Unicode code points> for more information.
3069
e0e4a6e3
FC
3070=item %s matches null string many times in regex; marked by S<<-- HERE> in
3071m/%s/
4a5d3a93
FC
3072
3073(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3074regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3075shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3076See L<perlre>.
f337b084 3077
de42a5a9 3078=item Maximal count of pending signals (%u) exceeded
2563cec5 3079
6903afa2 3080(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3081usually indicates that your operating system tried to deliver signals
3082too fast (with a very high priority), starving the perl process from
3083resources it would need to reach a point where it can process signals
6903afa2 3084safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3085
25f58aea
PN
3086=item "%s" may clash with future reserved word
3087
3088(W) This warning may be due to running a perl5 script through a perl4
3089interpreter, especially if the word that is being warned about is
3090"use" or "my".
3091
0d2487cd 3092=item '%' may not be used in pack
6df41af2
GS
3093
3094(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3095checksumming process loses information, and you can't go the other way.
3096See L<perlfunc/unpack>.
6df41af2 3097
a0d0e21e
LW
3098=item Method for operation %s not found in package %s during blessing
3099
3100(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3101doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3102
3cdd684c
TP
3103=item Method %s not permitted
3104
3105See Server error.
3106
a0d0e21e
LW
3107=item Might be a runaway multi-line %s string starting on line %d
3108
3109(S) An advisory indicating that the previous error may have been caused
3110by a missing delimiter on a string or pattern, because it eventually
3111ended earlier on the current line.
3112
3113=item Misplaced _ in number
3114
d4ced10d
JH
3115(W syntax) An underscore (underbar) in a numeric constant did not
3116separate two digits.
a0d0e21e 3117
7baa4690
HS
3118=item Missing argument in %s
3119
3664866e
AB
3120(W missing) You called a function with fewer arguments than other
3121arguments you supplied indicated would be needed.
3122
3123Currently only emitted when a printf-type format required more
3124arguments than were supplied, but might be used in the future for
3125other cases where we can statically determine that arguments to
3126functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3127
9e81e6a1
RGS
3128=item Missing argument to -%c
3129
3130(F) The argument to the indicated command line switch must follow
3131immediately after the switch, without intervening spaces.
3132
ff3f963a 3133=item Missing braces on \N{}
423cee85 3134
e0e4a6e3 3135=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3136
4a2d328f 3137(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3138double-quotish context. This can also happen when there is a space
3139(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3140This modifier does not change the requirement that the brace immediately
3141follow the C<\N>.
423cee85 3142
f0a2b745
KW
3143=item Missing braces on \o{}
3144
3145(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3146
a0d0e21e
LW
3147=item Missing comma after first argument to %s function
3148
3149(F) While certain functions allow you to specify a filehandle or an
3150"indirect object" before the argument list, this ain't one of them.
3151
06eaf0bc
GS
3152=item Missing command in piped open
3153
be771a83
GS
3154(W pipe) You used the C<open(FH, "| command")> or
3155C<open(FH, "command |")> construction, but the command was missing or
3156blank.
06eaf0bc 3157
961ce445
RGS
3158=item Missing control char name in \c
3159
3160(F) A double-quoted string ended with "\c", without the required control
3161character name.
3162
591f5ca2
FC
3163=item Missing ']' in prototype for %s : %s
3164
bfe11873 3165(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3166
8767b1ab 3167=item Missing name in "%s sub"
6df41af2 3168
87444db5 3169(F) The syntax for lexically scoped subroutines requires that
be771a83 3170they have a name with which they can be found.
6df41af2
GS
3171
3172=item Missing $ on loop variable
3173
be771a83
GS
3174(F) Apparently you've been programming in B<csh> too much. Variables
3175are always mentioned with the $ in Perl, unlike in the shells, where it
3176can vary from one line to the next.
6df41af2 3177
cc507455 3178=item (Missing operator before %s?)
748a9306 3179
56da5a46
RGS
3180(S syntax) This is an educated guess made in conjunction with the message
3181"%s found where operator expected". Often the missing operator is a comma.
748a9306 3182
f51551f7
FC
3183=item Missing or undefined argument to require
3184
3185(F) You tried to call require with no argument or with an undefined
3186value as an argument. Require expects either a package name or a
3187file-specification as an argument. See L<perlfunc/require>.
3188
e0e4a6e3 3189=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3190
ff3f963a
KW
3191(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3192
4a68bf9d 3193=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3194
d32207c9
FC
3195(F) C<\N> has two meanings.
3196
3197The traditional one has it followed by a name enclosed in braces,
3198meaning the character (or sequence of characters) given by that
fa816bf3 3199name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3200double-quoted strings and regular expression patterns. In patterns,
3201it doesn't have the meaning an unescaped C<*> does.
3202
3203Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3204in patterns, namely to match a non-newline character. (This is short
3205for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3206
3207This can lead to some ambiguities. When C<\N> is not followed immediately
3208by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3209form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3210means to match the given quantity of non-newlines (in these examples,
32113; and 5 or more, respectively). In all other case, where there is a
3212C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3213
3214However, if there is no matching C<}>, Perl doesn't know if it was
3215mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3216If you meant the former, add the right brace; if you meant the latter,
3217escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3218
d98d5fff 3219=item Missing right curly or square bracket
a0d0e21e 3220
be771a83
GS
3221(F) The lexer counted more opening curly or square brackets than closing
3222ones. As a general rule, you'll find it's missing near the place you
3223were last editing.
a0d0e21e 3224
6df41af2
GS
3225=item (Missing semicolon on previous line?)
3226
56da5a46
RGS
3227(S syntax) This is an educated guess made in conjunction with the message
3228"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3229the previous line just because you saw this message.
3230
a0d0e21e
LW
3231=item Modification of a read-only value attempted
3232
3233(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3234constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3235catches that. But an easy way to do the same thing is:
3236
3237 sub mod { $_[0] = 1 }
3238 mod(2);
3239
3240Another way is to assign to a substr() that's off the end of the string.
3241
c5674021
PDF
3242Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3243is aliased to a constant in the look I<LIST>:
3244
b7e4ecc1
FC
3245 $x = 1;
3246 foreach my $n ($x, 2) {
3247 $n *= 2; # modifies the $x, but fails on attempt to
3248 } # modify the 2
c5674021 3249
7a4340ed 3250=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3251
3252(F) You tried to make an array value spring into existence, and the
3253subscript was probably negative, even counting from end of the array
3254backwards.
3255
7a4340ed 3256=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3257
be771a83
GS
3258(P) You tried to make a hash value spring into existence, and it
3259couldn't be created for some peculiar reason.
a0d0e21e
LW
3260
3261=item Module name must be constant
3262
3263(F) Only a bare module name is allowed as the first argument to a "use".
3264
be98fb35 3265=item Module name required with -%c option
6df41af2 3266
be98fb35
GS
3267(F) The C<-M> or C<-m> options say that Perl should load some module, but
3268you omitted the name of the module. Consult L<perlrun> for full details
3269about C<-M> and C<-m>.
6df41af2 3270
fe13d51d 3271=item More than one argument to '%s' open
ed9aa3b7 3272
6903afa2 3273(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3274can happen if you are trying to open a pipe to a command that takes a
3275list of arguments, but have forgotten to specify a piped open mode.
3276See L<perlfunc/open> for details.
3277
85396b18
FC
3278=item mprotect for COW string %p %u failed with %d
3279
3280(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3281L<perlguts/"Copy on Write">), but a shared string buffer
3282could not be made read-only.
3283
92951bce
FC
3284=item mprotect for %p %u failed with %d
3285
85396b18
FC
3286(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3287but an op tree could not be made read-only.
3288
3289=item mprotect RW for COW string %p %u failed with %d
3290
3291(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3292L<perlguts/"Copy on Write">), but a read-only shared string
3293buffer could not be made mutable.
3294
92951bce
FC
3295=item mprotect RW for %p %u failed with %d
3296
3297(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3298L<perlhacktips>), but a read-only op tree could not be made
3299mutable before freeing the ops.
92951bce 3300
a0d0e21e
LW
3301=item msg%s not implemented
3302
3303(F) You don't have System V message IPC on your system.
3304
3305=item Multidimensional syntax %s not supported
3306
75b44862
GS
3307(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3308They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3309
49704364 3310=item '/' must follow a numeric type in unpack
6df41af2 3311
49704364
LW
3312(F) You had an unpack template that contained a '/', but this did not
3313follow some unpack specification producing a numeric value.
3314See L<perlfunc/pack>.
6df41af2
GS
3315
3316=item "my sub" not yet implemented
3317
be771a83
GS
3318(F) Lexically scoped subroutines are not yet implemented. Don't try
3319that yet.
6df41af2 3320
a21eb52b
FC
3321=item "my" subroutine %s can't be in a package
3322
3323(F) Lexically scoped subroutines aren't in a package, so it doesn't make
3324sense to try to declare one with a package qualifier on the front.