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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
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53=item Aliasing via reference is experimental
54
55(S experimental::refaliasing) This warning is emitted if you use
56a reference constructor on the left-hand side of an assignment to
57alias one variable to another. Simply suppress the warning if you
58want to use the feature, but know that in doing so you are taking
59the risk of using an experimental feature which may change or be
60removed in a future Perl version:
61
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
64 \$x = \$y;
65
de42a5a9 66=item Allocation too large: %x
a0d0e21e 67
6df41af2 68(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 69
04f74579 70=item '%c' allowed only after types %s in %s
ef54e1a4 71
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72(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73after certain types. See L<perlfunc/pack>.
ef54e1a4 74
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75=item alpha->numify() is lossy
76
77(W numeric) An alpha version can not be numified without losing
78information.
79
6df41af2 80=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 81
75b44862 82(W ambiguous) A subroutine you have declared has the same name as a Perl
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83keyword, and you have used the name without qualification for calling
84one or the other. Perl decided to call the builtin because the
85subroutine is not imported.
43192e07 86
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87To force interpretation as a subroutine call, either put an ampersand
88before the subroutine name, or qualify the name with its package.
89Alternatively, you can import the subroutine (or pretend that it's
90imported with the C<use subs> pragma).
43192e07 91
6df41af2 92To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 93on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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94to be an object method (see L<perlsub/"Subroutine Attributes"> or
95L<attributes>).
43192e07 96
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97=item Ambiguous range in transliteration operator
98
99(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
100all. To include a C<-> character in a transliteration, put it either
101first or last. (In the past, C<tr/a-z-0//> was synonymous with
102C<tr/a-y//>, which was probably not what you would have expected.)
103
6df41af2 104=item Ambiguous use of %s resolved as %s
43192e07 105
7c7af292 106(S ambiguous) You said something that may not be interpreted the way
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107you thought. Normally it's pretty easy to disambiguate it by supplying
108a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 109
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110=item Ambiguous use of -%s resolved as -&%s()
111
112(S ambiguous) You wrote something like C<-foo>, which might be the
113string C<"-foo">, or a call to the function C<foo>, negated. If you meant
114the string, just write C<"-foo">. If you meant the function call,
115write C<-foo()>.
116
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117=item Ambiguous use of %c resolved as operator %c
118
7c7af292 119(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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120bitwise and, and multiplication) I<and> initial special characters
121(denoting hashes, subroutines and typeglobs), and you said something
122like C<*foo * foo> that might be interpreted as either of them. We
123assumed you meant the infix operator, but please try to make it more
124clear -- in the example given, you might write C<*foo * foo()> if you
125really meant to multiply a glob by the result of calling a function.
d8225693 126
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127=item Ambiguous use of %c{%s} resolved to %c%s
128
129(W ambiguous) You wrote something like C<@{foo}>, which might be
130asking for the variable C<@foo>, or it might be calling a function
131named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 132the variable, you can just write C<@foo>. If you wanted to call the
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133function, write C<@{foo()}> ... or you could just not have a variable
134and a function with the same name, and save yourself a lot of trouble.
135
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136=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
137
138=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 139
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140(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
141the name of a Perl keyword), which might be looking for element number
1422 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
143might have meant to pass an anonymous arrayref to the function named
144foo, and then do a scalar deref on the value it returns. If you meant
145that, write C<${foo([2])}>.
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146
147In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
148to disambiguate between array subscripts and character classes.
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149C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
150by the character class C<[2345]>. If an array subscript is what you
151want, you can avoid the warning by changing C</${length[2345]}/> to the
152unsightly C</${\$length[2345]}/>, by renaming your array to something
153that does not coincide with a built-in keyword, or by simply turning
154off warnings with C<no warnings 'ambiguous';>.
4da60377 155
6df41af2 156=item '|' and '<' may not both be specified on command line
a0d0e21e 157
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158(F) An error peculiar to VMS. Perl does its own command line
159redirection, and found that STDIN was a pipe, and that you also tried to
160redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 161
6df41af2 162=item '|' and '>' may not both be specified on command line
1028017a 163
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164(F) An error peculiar to VMS. Perl does its own command line
165redirection, and thinks you tried to redirect stdout both to a file and
166into a pipe to another command. You need to choose one or the other,
167though nothing's stopping you from piping into a program or Perl script
168which 'splits' output into two streams, such as
1028017a 169
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170 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
171 while (<STDIN>) {
172 print;
173 print OUT;
174 }
175 close OUT;
c9f97d15 176
6df41af2 177=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 178
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179(W misc) The pattern match (C<//>), substitution (C<s///>), and
180transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 181one of them to an array or a hash, it will convert the array or hash to
ac036724 182a scalar value (the length of an array, or the population info of a
183hash) and then work on that scalar value. This is probably not what
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184you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
185alternatives.
eb6e2d6f 186
6df41af2 187=item Arg too short for msgsnd
76cd736e 188
6df41af2 189(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 190
f86702cc 191=item Argument "%s" isn't numeric%s
a0d0e21e 192
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193(W numeric) The indicated string was fed as an argument to an operator
194that expected a numeric value instead. If you're fortunate the message
195will identify which operator was so unfortunate.
a0d0e21e 196
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197Note that for the C<Inf> and C<NaN> (infinity and not-a-number) the
198definition of "numeric" is somewhat unusual: the strings themselves
199(like "Inf") are considered numeric, and anything following them is
200considered non-numeric.
201
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202=item Argument list not closed for PerlIO layer "%s"
203
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204(W layer) When pushing a layer with arguments onto the Perl I/O
205system you forgot the ) that closes the argument list. (Layers
206take care of transforming data between external and internal
207representations.) Perl stopped parsing the layer list at this
208point and did not attempt to push this layer. If your program
209didn't explicitly request the failing operation, it may be the
210result of the value of the environment variable PERLIO.
b4581f09 211
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212=item Argument "%s" treated as 0 in increment (++)
213
214(W numeric) The indicated string was fed as an argument to the C<++>
215operator which expects either a number or a string matching
216C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
217Auto-decrement> for details.
218
637494ac 219=item Array passed to stat will be coerced to a scalar%s
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220
221(W syntax) You called stat() on an array, but the array will be
222coerced to a scalar - the number of elements in the array.
223
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224=item A signature parameter must start with '$', '@' or '%'
225
226(F) Each subroutine signature parameter declaration must start with a valid
227sigil; for example:
228
229 sub foo ($a, $, $b = 1, @c) {}
230
231=item A slurpy parameter may not have a default value
232
233(F) Only scalar subroutine signature parameters may have a default value;
234for example:
235
236 sub foo ($a = 1) {} # legal
237 sub foo (@a = (1)) {} # invalid
238 sub foo (%a = (a => b)) {} # invalid
239
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240=item assertion botched: %s
241
21b5e840 242(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 243
0eacef8e 244=item Assertion %s failed: file "%s", line %d
a0d0e21e 245
21b5e840 246(X) A general assertion failed. The file in question must be examined.
a0d0e21e 247
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248=item Assigned value is not a reference
249
250(F) You tried to assign something that was not a reference to an lvalue
251reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
252C<\$x = \$y>.
253
254=item Assigned value is not %s reference
255
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256(F) You tried to assign a reference to a reference constructor, but the
257two references were not of the same type. You cannot alias a scalar to
258an array, or an array to a hash; the two types must match.
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259
260 \$x = \@y; # error
261 \@x = \%y; # error
262 $y = [];
263 \$x = $y; # error; did you mean \$y?
264
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265=item Assigning non-zero to $[ is no longer possible
266
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267(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
268the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 269
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270=item Assignment to both a list and a scalar
271
272(F) If you assign to a conditional operator, the 2nd and 3rd arguments
273must either both be scalars or both be lists. Otherwise Perl won't
274know which context to supply to the right side.
275
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276=item Assuming NOT a POSIX class since %s in regex; marked by S<<-- HERE> in m/%s/
277
278(W regexp) You had something like these:
279
280 [[:alnum]]
281 [[:digit:xyz]
282
283They look like they might have been meant to be the POSIX classes
284C<[:alnum:]> or C<[:digit:]>. If so, they should be written:
285
286 [[:alnum:]]
287 [[:digit:]xyz]
288
289Since these aren't legal POSIX class specifications, but are legal
290bracketed character classes, Perl treats them as the latter. In the
291first example, it matches the characters C<":">, C<"[">, C<"a">, C<"l">,
292C<"m">, C<"n">, and C<"u">.
293
294If these weren't meant to be POSIX classes, this warning message is
295spurious, and can be suppressed by reordering things, such as
296
297 [[al:num]]
298
299or
300
301 [[:munla]]
302
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303=item <> at require-statement should be quotes
304
305(F) You wrote C<< require <file> >> when you should have written
306C<require 'file'>.
307
2393f1b9 308=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 309
49293501 310(F) The failing code has attempted to get or set a key which is not in
2393f1b9 311the current set of allowed keys of a restricted hash.
49293501 312
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313=item Attempt to bless into a freed package
314
315(F) You wrote C<bless $foo> with one argument after somehow causing
316the current package to be freed. Perl cannot figure out what to
317do, so it throws up in hands in despair.
318
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319=item Attempt to bless into a reference
320
321(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 322the name of the package to bless the resulting object into. You've
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323supplied instead a reference to something: perhaps you wrote
324
325 bless $self, $proto;
326
327when you intended
328
329 bless $self, ref($proto) || $proto;
330
331If you actually want to bless into the stringified version
332of the reference supplied, you need to stringify it yourself, for
333example by:
334
335 bless $self, "$proto";
336
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337=item Attempt to clear deleted array
338
339(S debugging) An array was assigned to when it was being freed.
340Freed values are not supposed to be visible to Perl code. This
341can also happen if XS code calls C<av_clear> from a custom magic
342callback on the array.
343
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344=item Attempt to delete disallowed key '%s' from a restricted hash
345
346(F) The failing code attempted to delete from a restricted hash a key
347which is not in its key set.
348
349=item Attempt to delete readonly key '%s' from a restricted hash
350
351(F) The failing code attempted to delete a key whose value has been
352declared readonly from a restricted hash.
353
de42a5a9 354=item Attempt to free non-arena SV: 0x%x
a0d0e21e 355
f84fe999 356(S internal) All SV objects are supposed to be allocated from arenas
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357that will be garbage collected on exit. An SV was discovered to be
358outside any of those arenas.
a0d0e21e 359
12578ffb 360=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 361
f84fe999 362(S internal) Perl maintains a reference-counted internal table of
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363strings to optimize the storage and access of hash keys and other
364strings. This indicates someone tried to decrement the reference count
365of a string that can no longer be found in the table.
bbce6d69 366
7d5b40b4 367=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 368
f84fe999 369(S debugging) Mortalized values are supposed to be freed by the
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370free_tmps() routine. This indicates that something else is freeing the
371SV before the free_tmps() routine gets a chance, which means that the
372free_tmps() routine will be freeing an unreferenced scalar when it does
373try to free it.
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374
375=item Attempt to free unreferenced glob pointers
376
f84fe999 377(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 378
7d5b40b4 379=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 380
8f7e4d2c 381(S internal) Perl went to decrement the reference count of a scalar to
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382see if it would go to 0, and discovered that it had already gone to 0
383earlier, and should have been freed, and in fact, probably was freed.
384This could indicate that SvREFCNT_dec() was called too many times, or
385that SvREFCNT_inc() was called too few times, or that the SV was
386mortalized when it shouldn't have been, or that memory has been
387corrupted.
a0d0e21e 388
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389=item Attempt to pack pointer to temporary value
390
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391(W pack) You tried to pass a temporary value (like the result of a
392function, or a computed expression) to the "p" pack() template. This
393means the result contains a pointer to a location that could become
394invalid anytime, even before the end of the current statement. Use
395literals or global values as arguments to the "p" pack() template to
396avoid this warning.
84902520 397
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398=item Attempt to reload %s aborted.
399
400(F) You tried to load a file with C<use> or C<require> that failed to
401compile once already. Perl will not try to compile this file again
402unless you delete its entry from %INC. See L<perlfunc/require> and
403L<perlvar/%INC>.
404
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405=item Attempt to set length of freed array
406
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407(W misc) You tried to set the length of an array which has
408been freed. You can do this by storing a reference to the
409scalar representing the last index of an array and later
410assigning through that reference. For example
1b20cd17
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411
412 $r = do {my @a; \$#a};
413 $$r = 503
414
b7a902f4 415=item Attempt to use reference as lvalue in substr
416
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417(W substr) You supplied a reference as the first argument to substr()
418used as an lvalue, which is pretty strange. Perhaps you forgot to
419dereference it first. See L<perlfunc/substr>.
b7a902f4 420
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421=item Attribute "locked" is deprecated
422
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423(D deprecated) You have used the attributes pragma to modify the
424"locked" attribute on a code reference. The :locked attribute is
425obsolete, has had no effect since 5005 threads were removed, and
426will be removed in a future release of Perl 5.
c32124fe 427
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428=item Attribute prototype(%s) discards earlier prototype attribute in same sub
429
430(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
431example. Since each sub can only have one prototype, the earlier
432declaration(s) are discarded while the last one is applied.
433
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434=item Attribute "unique" is deprecated
435
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436(D deprecated) You have used the attributes pragma to modify
437the "unique" attribute on an array, hash or scalar reference.
438The :unique attribute has had no effect since Perl 5.8.8, and
439will be removed in a future release of Perl 5.
f1a3ce43 440
ccce04a4
FC
441=item av_reify called on tied array
442
443(S debugging) This indicates that something went wrong and Perl got I<very>
444confused about C<@_> or C<@DB::args> being tied.
445
de42a5a9 446=item Bad arg length for %s, is %u, should be %d
a0d0e21e 447
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448(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
449or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 450S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
a0d0e21e
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451S<sizeof(struct shmid_ds *)>.
452
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453=item Bad evalled substitution pattern
454
496a33f5 455(F) You've used the C</e> switch to evaluate the replacement for a
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456substitution, but perl found a syntax error in the code to evaluate,
457most likely an unexpected right brace '}'.
458
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459=item Bad filehandle: %s
460
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461(F) A symbol was passed to something wanting a filehandle, but the
462symbol has no filehandle associated with it. Perhaps you didn't do an
463open(), or did it in another package.
a0d0e21e
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464
465=item Bad free() ignored
466
be771a83 467(S malloc) An internal routine called free() on something that had never
fa816bf3 468been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 469setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 470
9ea8bc6d 471This message can be seen quite often with DB_File on systems with "hard"
6903afa2 472dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 473which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 474
aa689395 475=item Bad hash
476
477(P) One of the internal hash routines was passed a null HV pointer.
478
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479=item Badly placed ()'s
480
481(A) You've accidentally run your script through B<csh> instead
482of Perl. Check the #! line, or manually feed your script into
483Perl yourself.
484
a7cb8dae 485=item Bad name after %s
a0d0e21e 486
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487(F) You started to name a symbol by using a package prefix, and then
488didn't finish the symbol. In particular, you can't interpolate outside
489of quotes, so
a0d0e21e
LW
490
491 $var = 'myvar';
492 $sym = mypack::$var;
493
494is not the same as
495
496 $var = 'myvar';
497 $sym = "mypack::$var";
498
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499=item Bad plugin affecting keyword '%s'
500
501(F) An extension using the keyword plugin mechanism violated the
502plugin API.
503
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504=item Bad realloc() ignored
505
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506(S malloc) An internal routine called realloc() on something that
507had never been malloc()ed in the first place. Mandatory, but can
508be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 509
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510=item Bad symbol for array
511
512(P) An internal request asked to add an array entry to something that
513wasn't a symbol table entry.
514
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515=item Bad symbol for dirhandle
516
517(P) An internal request asked to add a dirhandle entry to something
518that wasn't a symbol table entry.
519
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520=item Bad symbol for filehandle
521
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522(P) An internal request asked to add a filehandle entry to something
523that wasn't a symbol table entry.
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524
525=item Bad symbol for hash
526
527(P) An internal request asked to add a hash entry to something that
528wasn't a symbol table entry.
529
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530=item Bad symbol for scalar
531
532(P) An internal request asked to add a scalar entry to something that
533wasn't a symbol table entry.
534
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535=item Bareword found in conditional
536
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537(W bareword) The compiler found a bareword where it expected a
538conditional, which often indicates that an || or && was parsed as part
539of the last argument of the previous construct, for example:
34d09196
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540
541 open FOO || die;
542
be771a83
GS
543It may also indicate a misspelled constant that has been interpreted as
544a bareword:
34d09196
GS
545
546 use constant TYPO => 1;
547 if (TYOP) { print "foo" }
548
549The C<strict> pragma is useful in avoiding such errors.
550
a52f2cce
NC
551=item Bareword in require contains "%s"
552
a52f2cce
NC
553=item Bareword in require maps to disallowed filename "%s"
554
09eb1f39 555=item Bareword in require maps to empty filename
5bad2b39 556
a52f2cce 557(F) The bareword form of require has been invoked with a filename which could
d4e5761f 558not have been generated by a valid bareword permitted by the parser. You
a52f2cce
NC
559shouldn't be able to get this error from Perl code, but XS code may throw it
560if it passes an invalid module name to C<Perl_load_module>.
561
5bad2b39
DM
562=item Bareword in require must not start with a double-colon: "%s"
563
564(F) In C<require Bare::Word>, the bareword is not allowed to start with a
d4e5761f 565double-colon. Write C<require ::Foo::Bar> as C<require Foo::Bar> instead.
5bad2b39 566
6df41af2
GS
567=item Bareword "%s" not allowed while "strict subs" in use
568
569(F) With "strict subs" in use, a bareword is only allowed as a
be771a83
GS
570subroutine identifier, in curly brackets or to the left of the "=>"
571symbol. Perhaps you need to predeclare a subroutine?
6df41af2
GS
572
573=item Bareword "%s" refers to nonexistent package
574
be771a83
GS
575(W bareword) You used a qualified bareword of the form C<Foo::>, but the
576compiler saw no other uses of that namespace before that point. Perhaps
577you need to predeclare a package?
6df41af2 578
a0d0e21e
LW
579=item BEGIN failed--compilation aborted
580
be771a83
GS
581(F) An untrapped exception was raised while executing a BEGIN
582subroutine. Compilation stops immediately and the interpreter is
583exited.
a0d0e21e 584
68dc0745 585=item BEGIN not safe after errors--compilation aborted
586
587(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
be771a83
GS
588implies a C<BEGIN {}>) after one or more compilation errors had already
589occurred. Since the intended environment for the C<BEGIN {}> could not
590be guaranteed (due to the errors), and since subsequent code likely
591depends on its correct operation, Perl just gave up.
68dc0745 592
c782d7ee 593=item \%d better written as $%d
6df41af2 594
be771a83
GS
595(W syntax) Outside of patterns, backreferences live on as variables.
596The use of backslashes is grandfathered on the right-hand side of a
597substitution, but stylistically it's better to use the variable form
598because other Perl programmers will expect it, and it works better if
599there are more than 9 backreferences.
6df41af2 600
252aa082
JH
601=item Binary number > 0b11111111111111111111111111111111 non-portable
602
e476b1b5 603(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
604(4294967295) and therefore non-portable between systems. See
605L<perlport> for more on portability concerns.
252aa082 606
69282e91 607=item bind() on closed socket %s
a0d0e21e 608
be771a83
GS
609(W closed) You tried to do a bind on a closed socket. Did you forget to
610check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 611
c289d2f7
JH
612=item binmode() on closed filehandle %s
613
614(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 615Check your control flow and number of arguments.
c289d2f7 616
c5a0f51a
JH
617=item Bit vector size > 32 non-portable
618
e476b1b5 619(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 620
043c750c 621=item Bizarre copy of %s
4633a7c4 622
be771a83 623(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 624copiable.
4633a7c4 625
5a25739d
FC
626=item Bizarre SvTYPE [%d]
627
434f489b 628(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
629encountered an invalid data type.
630
b927b7e9 631=item Both or neither range ends should be Unicode in regex; marked by
6e8a73f2 632S<<-- HERE> in m/%s/
b927b7e9
KW
633
634(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
635
636In a bracketed character class in a regular expression pattern, you
637had a range which has exactly one end of it specified using C<\N{}>, and
638the other end is specified using a non-portable mechanism. Perl treats
639the range as a Unicode range, that is, all the characters in it are
640considered to be the Unicode characters, and which may be different code
641points on some platforms Perl runs on. For example, C<[\N{U+06}-\x08]>
642is treated as if you had instead said C<[\N{U+06}-\N{U+08}]>, that is it
643matches the characters whose code points in Unicode are 6, 7, and 8.
644But that C<\x08> might indicate that you meant something different, so
645the warning gets raised.
646
f675dbe5
CB
647=item Buffer overflow in prime_env_iter: %s
648
be771a83
GS
649(W internal) A warning peculiar to VMS. While Perl was preparing to
650iterate over %ENV, it encountered a logical name or symbol definition
651which was too long, so it was truncated to the string shown.
f675dbe5 652
a0d0e21e
LW
653=item Callback called exit
654
4929bf7b 655(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
656exited by calling exit.
657
6df41af2 658=item %s() called too early to check prototype
f675dbe5 659
be771a83
GS
660(W prototype) You've called a function that has a prototype before the
661parser saw a definition or declaration for it, and Perl could not check
662that the call conforms to the prototype. You need to either add an
663early prototype declaration for the subroutine in question, or move the
664subroutine definition ahead of the call to get proper prototype
665checking. Alternatively, if you are certain that you're calling the
666function correctly, you may put an ampersand before the name to avoid
667the warning. See L<perlsub>.
f675dbe5 668
56feebad
FC
669=item Calling POSIX::%s() is deprecated
670
671(D deprecated) You called a function whose use is deprecated. See
672the function's name in L<POSIX> for details.
673
0c7df902
JH
674=item Cannot chr %f
675
676(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
677
5dee29d4 678=item Cannot compress %f in pack
0c7df902 679
5dee29d4
JH
680(F) You tried compressing an infinity or not-a-number as an unsigned
681integer with BER, which makes no sense.
0c7df902 682
49704364 683=item Cannot compress integer in pack
0258719b 684
717feafc
JH
685(F) An argument to pack("w",...) was too large to compress.
686The BER compressed integer format can only be used with positive
687integers, and you attempted to compress a very large number (> 1e308).
688See L<perlfunc/pack>.
0258719b 689
49704364 690=item Cannot compress negative numbers in pack
0258719b
NC
691
692(F) An argument to pack("w",...) was negative. The BER compressed integer
693format can only be used with positive integers. See L<perlfunc/pack>.
694
5c1f4d79
NC
695=item Cannot convert a reference to %s to typeglob
696
6903afa2
FC
697(F) You manipulated Perl's symbol table directly, stored a reference
698in it, then tried to access that symbol via conventional Perl syntax.
699The access triggers Perl to autovivify that typeglob, but it there is
700no legal conversion from that type of reference to a typeglob.
5c1f4d79 701
4040665a 702=item Cannot copy to %s
ba2fdce6
NC
703
704(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 705be directly assigned to.
ba2fdce6 706
b5d97229
RGS
707=item Cannot find encoding "%s"
708
709(S io) You tried to apply an encoding that did not exist to a filehandle,
710either with open() or binmode().
711
0c7df902
JH
712=item Cannot pack %f with '%c'
713
5dee29d4 714(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
715which makes no sense.
716
717=item Cannot printf %f with '%c'
718
719(F) You tried printing an infinity or not-a-number as a character (%c),
720which makes no sense. Maybe you meant '%s', or just stringifying it?
721
7355df7e
FC
722=item Cannot set tied @DB::args
723
724(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
725is not supported. (Before this error was added, it used to crash.)
726
ce65bc73
FC
727=item Cannot tie unreifiable array
728
729(P) You somehow managed to call C<tie> on an array that does not
730keep a reference count on its arguments and cannot be made to
731do so. Such arrays are not even supposed to be accessible to
732Perl code, but are only used internally.
733
46e58bd2
AC
734=item Cannot yet reorder sv_catpvfn() arguments from va_list
735
736(F) Some XS code tried to use C<sv_catpvfn()> or a related function with a
737format string that specifies explicit indexes for some of the elements, and
d4e5761f
FC
738using a C-style variable-argument list (a C<va_list>). This is not currently
739supported. XS authors wanting to do this must instead construct a C array
740of C<SV*> scalars containing the arguments.
46e58bd2 741
96ebfdd7
RK
742=item Can only compress unsigned integers in pack
743
744(F) An argument to pack("w",...) was not an integer. The BER compressed
745integer format can only be used with positive integers, and you attempted
746to compress something else. See L<perlfunc/pack>.
747
a0d0e21e
LW
748=item Can't bless non-reference value
749
750(F) Only hard references may be blessed. This is how Perl "enforces"
751encapsulation of objects. See L<perlobj>.
752
dc57907a
RGS
753=item Can't "break" in a loop topicalizer
754
0d863452 755(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 756a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
757
758=item Can't "break" outside a given block
dc57907a 759
0d863452
RH
760(F) You called C<break>, but you're not inside a C<given> block.
761
6df41af2
GS
762=item Can't call method "%s" on an undefined value
763
764(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
765object reference or package name contains an undefined value. Something
766like this will reproduce the error:
6df41af2
GS
767
768 $BADREF = undef;
769 process $BADREF 1,2,3;
770 $BADREF->process(1,2,3);
771
a0d0e21e
LW
772=item Can't call method "%s" on unblessed reference
773
54310121 774(F) A method call must know in what package it's supposed to run. It
be771a83
GS
775ordinarily finds this out from the object reference you supply, but you
776didn't supply an object reference in this case. A reference isn't an
777object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
778
779=item Can't call method "%s" without a package or object reference
780
781(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
782object reference or package name contains an expression that returns a
783defined value which is neither an object reference nor a package name.
72b5445b
GS
784Something like this will reproduce the error:
785
786 $BADREF = 42;
787 process $BADREF 1,2,3;
788 $BADREF->process(1,2,3);
789
dfe378f1
FC
790=item Can't call mro_isa_changed_in() on anonymous symbol table
791
792(P) Perl got confused as to whether a hash was a plain hash or a
793symbol table hash when trying to update @ISA caches.
794
2bf7e7b2
FC
795=item Can't call mro_method_changed_in() on anonymous symbol table
796
797(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
798not attached to the symbol table.
799
a0d0e21e
LW
800=item Can't chdir to %s
801
f703fc96 802(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
803that you can chdir to, possibly because it doesn't exist.
804
0545a864 805=item Can't check filesystem of script "%s" for nosuid
104d25b7 806
be771a83
GS
807(P) For some reason you can't check the filesystem of the script for
808nosuid.
104d25b7 809
22e74366 810=item Can't coerce %s to %s in %s
a0d0e21e
LW
811
812(F) Certain types of SVs, in particular real symbol table entries
55497cff 813(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
814say things like:
815
816 *foo += 1;
817
818You CAN say
819
820 $foo = *foo;
821 $foo += 1;
822
823but then $foo no longer contains a glob.
824
0d863452 825=item Can't "continue" outside a when block
dc57907a 826
0d863452
RH
827(F) You called C<continue>, but you're not inside a C<when>
828or C<default> block.
829
a0d0e21e
LW
830=item Can't create pipe mailbox
831
be771a83
GS
832(P) An error peculiar to VMS. The process is suffering from exhausted
833quotas or other plumbing problems.
a0d0e21e 834
eb64745e
GS
835=item Can't declare %s in "%s"
836
30c282f6
NC
837(F) Only scalar, array, and hash variables may be declared as "my", "our" or
838"state" variables. They must have ordinary identifiers as names.
a0d0e21e 839
fc7debfb
FC
840=item Can't "default" outside a topicalizer
841
842(F) You have used a C<default> block that is neither inside a
843C<foreach> loop nor a C<given> block. (Note that this error is
844issued on exit from the C<default> block, so you won't get the
845error if you use an explicit C<continue>.)
846
a2162cd9
FC
847=item Can't do inplace edit: %s is not a regular file
848
849(S inplace) You tried to use the B<-i> switch on a special file, such as
850a file in /dev, a FIFO or an uneditable directory. The file was ignored.
851
852=item Can't do inplace edit on %s: %s
853
854(S inplace) The creation of the new file failed for the indicated
855reason.
856
857=item Can't do inplace edit without backup
858
859(F) You're on a system such as MS-DOS that gets confused if you try
860reading from a deleted (but still opened) file. You have to say
861C<-i.bak>, or some such.
862
863=item Can't do inplace edit: %s would not be unique
864
865(S inplace) Your filesystem does not support filenames longer than 14
866characters and Perl was unable to create a unique filename during
867inplace editing with the B<-i> switch. The file was ignored.
868
ab0b796c
KW
869=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
870
871(W locale) You are 1) running under "C<use locale>"; 2) the current
872locale is not a UTF-8 one; 3) you tried to do the designated case-change
873operation on the specified Unicode character; and 4) the result of this
874operation would mix Unicode and locale rules, which likely conflict.
875Mixing of different rule types is forbidden, so the operation was not
876done; instead the result is the indicated value, which is the best
877available that uses entirely Unicode rules. That turns out to almost
878always be the original character, unchanged.
879
880It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
881this issue is one of the reasons why. This warning is raised when
882Unicode rules would normally cause the result of this operation to
883contain a character that is in the range specified by the locale,
8840..255, and hence is subject to the locale's rules, not Unicode's.
885
886If you are using locale purely for its characteristics related to things
887like its numeric and time formatting (and not C<LC_CTYPE>), consider
888using a restricted form of the locale pragma (see L<perllocale/The "use
889locale" pragma>) like "S<C<use locale ':not_characters'>>".
890
891Note that failed case-changing operations done as a result of
892case-insensitive C</i> regular expression matching will show up in this
893warning as having the C<fc> operation (as that is what the regular
894expression engine calls behind the scenes.)
895
a0d0e21e
LW
896=item Can't do waitpid with flags
897
be771a83
GS
898(F) This machine doesn't have either waitpid() or wait4(), so only
899waitpid() without flags is emulated.
a0d0e21e 900
a0d0e21e
LW
901=item Can't emulate -%s on #! line
902
be771a83
GS
903(F) The #! line specifies a switch that doesn't make sense at this
904point. For example, it'd be kind of silly to put a B<-x> on the #!
905line.
a0d0e21e 906
1109a392
MHM
907=item Can't %s %s-endian %ss on this platform
908
909(F) Your platform's byte-order is neither big-endian nor little-endian,
910or it has a very strange pointer size. Packing and unpacking big- or
911little-endian floating point values and pointers may not be possible.
912See L<perlfunc/pack>.
913
a0d0e21e
LW
914=item Can't exec "%s": %s
915
d1be9408 916(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
917named program for the indicated reason. Typical reasons include: the
918permissions were wrong on the file, the file wasn't found in
919C<$ENV{PATH}>, the executable in question was compiled for another
920architecture, or the #! line in a script points to an interpreter that
921can't be run for similar reasons. (Or maybe your system doesn't support
922#! at all.)
a0d0e21e
LW
923
924=item Can't exec %s
925
be771a83
GS
926(F) Perl was trying to execute the indicated program for you because
927that's what the #! line said. If that's not what you wanted, you may
928need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
929
930=item Can't execute %s
931
be771a83
GS
932(F) You used the B<-S> switch, but the copies of the script to execute
933found in the PATH did not have correct permissions.
2a92aaa0 934
6df41af2 935=item Can't find an opnumber for "%s"
2a92aaa0 936
be771a83
GS
937(F) A string of a form C<CORE::word> was given to prototype(), but there
938is no builtin with the name C<word>.
6df41af2
GS
939
940=item Can't find label %s
941
be771a83
GS
942(F) You said to goto a label that isn't mentioned anywhere that it's
943possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
944
945=item Can't find %s on PATH
946
be771a83
GS
947(F) You used the B<-S> switch, but the script to execute could not be
948found in the PATH.
a0d0e21e 949
6df41af2 950=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 951
be771a83
GS
952(F) You used the B<-S> switch, but the script to execute could not be
953found in the PATH, or at least not with the correct permissions. The
954script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
955
956=item Can't find string terminator %s anywhere before EOF
957
be771a83
GS
958(F) Perl strings can stretch over multiple lines. This message means
959that the closing delimiter was omitted. Because bracketed quotes count
960nesting levels, the following is missing its final parenthesis:
a0d0e21e 961
fb73857a 962 print q(The character '(' starts a side comment.);
963
97b3d10f 964If you're getting this error from a here-document, you may have
b6b8cb97
FC
965included unseen whitespace before or after your closing tag or there
966may not be a linebreak after it. A good programmer's editor will have
967a way to help you find these characters (or lack of characters). See
968L<perlop> for the full details on here-documents.
a0d0e21e 969
660a4616
TS
970=item Can't find Unicode property definition "%s"
971
29f52644
KW
972=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
973
974(F) The named property which you specified via C<\p> or C<\P> is not one
975known to Perl. Perhaps you misspelled the name? See
e1b711da 976L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
977for a complete list of available official
978properties. If it is a
979L<user-defined property|perlunicode/User-Defined Character Properties>
980it must have been defined by the time the regular expression is
981matched.
982
983If you didn't mean to use a Unicode property, escape the C<\p>, either
984by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 985until C<\E>).
660a4616 986
b3647a36 987=item Can't fork: %s
a0d0e21e 988
be771a83
GS
989(F) A fatal error occurred while trying to fork while opening a
990pipeline.
a0d0e21e 991
b3647a36
SR
992=item Can't fork, trying again in 5 seconds
993
c973c02e 994(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
995after five seconds.
996
748a9306
LW
997=item Can't get filespec - stale stat buffer?
998
be771a83
GS
999(S) A warning peculiar to VMS. This arises because of the difference
1000between access checks under VMS and under the Unix model Perl assumes.
1001Under VMS, access checks are done by filename, rather than by bits in
1002the stat buffer, so that ACLs and other protections can be taken into
1003account. Unfortunately, Perl assumes that the stat buffer contains all
1004the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 1005the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
1006the device name and FID present in the stat buffer, but this works only
1007if you haven't made a subsequent call to the CRTL stat() routine,
1008because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
1009appears, the name lookup failed, and the access-checking routine gave up
1010and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
1011routine knows about the Perl C<stat> operator and file tests, so you
1012shouldn't ever see this warning in response to a Perl command; it arises
1013only if some internal code takes stat buffers lightly.)
748a9306 1014
a0d0e21e
LW
1015=item Can't get pipe mailbox device name
1016
be771a83
GS
1017(P) An error peculiar to VMS. After creating a mailbox to act as a
1018pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
1019
1020=item Can't get SYSGEN parameter value for MAXBUF
1021
748a9306
LW
1022(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
1023mailbox buffers to be, and didn't get an answer.
a0d0e21e 1024
6df41af2 1025=item Can't "goto" into the middle of a foreach loop
a0d0e21e 1026
be771a83
GS
1027(F) A "goto" statement was executed to jump into the middle of a foreach
1028loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
1029
1030=item Can't "goto" out of a pseudo block
1031
be771a83
GS
1032(F) A "goto" statement was executed to jump out of what might look like
1033a block, except that it isn't a proper block. This usually occurs if
1034you tried to jump out of a sort() block or subroutine, which is a no-no.
1035See L<perlfunc/goto>.
a0d0e21e 1036
5a25739d
FC
1037=item Can't goto subroutine from an eval-%s
1038
1039(F) The "goto subroutine" call can't be used to jump out of an eval
1040"string" or block.
1041
9850bf21 1042=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 1043
9850bf21
RH
1044(F) The "goto subroutine" call can't be used to jump out of the
1045comparison sub for a sort(), or from a similar callback (such
1046as the reduce() function in List::Util).
1047
6df41af2
GS
1048=item Can't goto subroutine outside a subroutine
1049
be771a83
GS
1050(F) The deeply magical "goto subroutine" call can only replace one
1051subroutine call for another. It can't manufacture one out of whole
1052cloth. In general you should be calling it out of only an AUTOLOAD
1053routine anyway. See L<perlfunc/goto>.
6df41af2 1054
0b5b802d
GS
1055=item Can't ignore signal CHLD, forcing to default
1056
be771a83
GS
1057(W signal) Perl has detected that it is being run with the SIGCHLD
1058signal (sometimes known as SIGCLD) disabled. Since disabling this
1059signal will interfere with proper determination of exit status of child
1060processes, Perl has reset the signal to its default value. This
1061situation typically indicates that the parent program under which Perl
1062may be running (e.g. cron) is being very careless.
0b5b802d 1063
e2c0f81f
DG
1064=item Can't kill a non-numeric process ID
1065
1066(F) Process identifiers must be (signed) integers. It is a fatal error to
1067attempt to kill() an undefined, empty-string or otherwise non-numeric
1068process identifier.
1069
6df41af2 1070=item Can't "last" outside a loop block
4633a7c4 1071
6df41af2 1072(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1073except that there's this itty bitty problem called there isn't a current
1074block. Note that an "if" or "else" block doesn't count as a "loopish"
1075block, as doesn't a block given to sort(), map() or grep(). You can
1076usually double the curlies to get the same effect though, because the
1077inner curlies will be considered a block that loops once. See
1078L<perlfunc/last>.
4633a7c4 1079
2c7d6b9c
RGS
1080=item Can't linearize anonymous symbol table
1081
1082(F) Perl tried to calculate the method resolution order (MRO) of a
1083package, but failed because the package stash has no name.
1084
b8170e59
JB
1085=item Can't load '%s' for module %s
1086
6903afa2
FC
1087(F) The module you tried to load failed to load a dynamic extension.
1088This may either mean that you upgraded your version of perl to one
1089that is incompatible with your old dynamic extensions (which is known
1090to happen between major versions of perl), or (more likely) that your
1091dynamic extension was built against an older version of the library
1092that is installed on your system. You may need to rebuild your old
1093dynamic extensions.
b8170e59 1094
748a9306
LW
1095=item Can't localize lexical variable %s
1096
2ba9eb46 1097(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1098lexical variable using "my" or "state". This is not allowed. If you
1099want to localize a package variable of the same name, qualify it with
1100the package name.
748a9306 1101
6df41af2 1102=item Can't localize through a reference
4727527e 1103
6df41af2
GS
1104(F) You said something like C<local $$ref>, which Perl can't currently
1105handle, because when it goes to restore the old value of whatever $ref
be771a83 1106pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1107that $ref will still be a reference.
4727527e 1108
ea071790 1109=item Can't locate %s
ec889f3a 1110
fa816bf3
FC
1111(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1112Perl looks for the file in all the locations mentioned in @INC, unless
1113the file name included the full path to the file. Perhaps you need
1114to set the PERL5LIB or PERL5OPT environment variable to say where the
1115extra library is, or maybe the script needs to add the library name
be771a83
GS
1116to @INC. Or maybe you just misspelled the name of the file. See
1117L<perlfunc/require> and L<lib>.
a0d0e21e 1118
6df41af2
GS
1119=item Can't locate auto/%s.al in @INC
1120
be771a83
GS
1121(F) A function (or method) was called in a package which allows
1122autoload, but there is no function to autoload. Most probable causes
1123are a misprint in a function/method name or a failure to C<AutoSplit>
1124the file, say, by doing C<make install>.
6df41af2 1125
b8170e59
JB
1126=item Can't locate loadable object for module %s in @INC
1127
1128(F) The module you loaded is trying to load an external library, like
d70d8e57 1129for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1130unable to locate this library. See L<DynaLoader>.
1131
a0d0e21e
LW
1132=item Can't locate object method "%s" via package "%s"
1133
1134(F) You called a method correctly, and it correctly indicated a package
1135functioning as a class, but that package doesn't define that particular
2ba9eb46 1136method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1137
8af56b9d
FC
1138=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1139to load "%s"?)
1140
1141(F) You called a method on a class that did not exist, and the method
1142could not be found in UNIVERSAL. This often means that a method
1143requires a package that has not been loaded.
1144
a0d0e21e
LW
1145=item Can't locate package %s for @%s::ISA
1146
be771a83
GS
1147(W syntax) The @ISA array contained the name of another package that
1148doesn't seem to exist.
a0d0e21e 1149
2f7da168
RK
1150=item Can't locate PerlIO%s
1151
1152(F) You tried to use in open() a PerlIO layer that does not exist,
1153e.g. open(FH, ">:nosuchlayer", "somefile").
1154
f4ad53f4 1155=item Can't make list assignment to %ENV on this system
3e3baf6d 1156
be771a83
GS
1157(F) List assignment to %ENV is not supported on some systems, notably
1158VMS.
3e3baf6d 1159
cd40cd58
NC
1160=item Can't make loaded symbols global on this platform while loading %s
1161
ff9c1ae8 1162(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1163that symbols from the stated file are made available globally within the
1164process, but that functionality is not available on this platform. Whilst
1165the module likely will still work, this may prevent the perl interpreter
1166from loading other XS-based extensions which need to link directly to
1167functions defined in the C or XS code in the stated file.
1168
a0d0e21e
LW
1169=item Can't modify %s in %s
1170
be771a83
GS
1171(F) You aren't allowed to assign to the item indicated, or otherwise try
1172to change it, such as with an auto-increment.
a0d0e21e 1173
54310121 1174=item Can't modify nonexistent substring
a0d0e21e
LW
1175
1176(P) The internal routine that does assignment to a substr() was handed
1177a NULL.
1178
0f948285 1179=item Can't modify non-lvalue subroutine call of &%s
6df41af2
GS
1180
1181(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1182such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1183
cf6e1fa1
FC
1184=item Can't modify reference to %s in %s assignment
1185
1186(F) Only a limited number of constructs can be used as the argument to a
1187reference constructor on the left-hand side of an assignment, and what
1188you used was not one of them. See L<perlref/Assigning to References>.
1189
1190=item Can't modify reference to localized parenthesized array in list
1191assignment
1192
1193(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1194it is not clear exactly what it should do. If you meant to make @array
1195refer to some other array, use C<\@array = \@other_array>. If you want to
1196make the elements of @array aliases of the scalars referenced on the
1197right-hand side, use C<\(@array) = @scalar_refs>.
1198
1199=item Can't modify reference to parenthesized hash in list assignment
1200
1201(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1202refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1203make the elements of %hash into aliases of the scalars referenced on the
1204right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1205
5f05dabc 1206=item Can't msgrcv to read-only var
a0d0e21e 1207
5f05dabc 1208(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1209buffer.
1210
6df41af2
GS
1211=item Can't "next" outside a loop block
1212
1213(F) A "next" statement was executed to reiterate the current block, but
1214there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1215count as a "loopish" block, as doesn't a block given to sort(), map() or
1216grep(). You can usually double the curlies to get the same effect
1217though, because the inner curlies will be considered a block that loops
1218once. See L<perlfunc/next>.
6df41af2 1219
a0d0e21e
LW
1220=item Can't open %s: %s
1221
c47ff5f1 1222(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1223filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1224switches, or explicitly, failed for the indicated reason. Usually
1225this is because you don't have read permission for a file which
1226you named on the command line.
1227
1228(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1229your operating system's equivalent) could not be opened.
a0d0e21e 1230
9a869a14
RGS
1231=item Can't open a reference
1232
1233(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1234using the 3-arg open() syntax:
9a869a14
RGS
1235
1236 open FH, '>', $ref;
1237
1238but your version of perl is compiled without perlio, and this form of
1239open is not supported.
1240
a0d0e21e
LW
1241=item Can't open bidirectional pipe
1242
be771a83
GS
1243(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1244You can try any of several modules in the Perl library to do this, such
1245as IPC::Open2. Alternately, direct the pipe's output to a file using
1246">", and then read it in under a different file handle.
a0d0e21e 1247
748a9306
LW
1248=item Can't open error file %s as stderr
1249
be771a83
GS
1250(F) An error peculiar to VMS. Perl does its own command line
1251redirection, and couldn't open the file specified after '2>' or '2>>' on
1252the command line for writing.
748a9306
LW
1253
1254=item Can't open input file %s as stdin
1255
be771a83
GS
1256(F) An error peculiar to VMS. Perl does its own command line
1257redirection, and couldn't open the file specified after '<' on the
1258command line for reading.
748a9306
LW
1259
1260=item Can't open output file %s as stdout
1261
be771a83
GS
1262(F) An error peculiar to VMS. Perl does its own command line
1263redirection, and couldn't open the file specified after '>' or '>>' on
1264the command line for writing.
748a9306
LW
1265
1266=item Can't open output pipe (name: %s)
1267
be771a83
GS
1268(P) An error peculiar to VMS. Perl does its own command line
1269redirection, and couldn't open the pipe into which to send data destined
1270for stdout.
748a9306 1271
3b1cf97d 1272=item Can't open perl script "%s": %s
a0d0e21e
LW
1273
1274(F) The script you specified can't be opened for the indicated reason.
1275
fa3aa65a
JC
1276If you're debugging a script that uses #!, and normally relies on the
1277shell's $PATH search, the -S option causes perl to do that search, so
1278you don't have to type the path or C<`which $scriptname`>.
1279
6df41af2
GS
1280=item Can't read CRTL environ
1281
1282(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1283from the CRTL's internal environment array and discovered the array was
1284missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1285or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1286searched.
6df41af2 1287
f3106bc8
LM
1288=item Can't redeclare "%s" in "%s"
1289
1290(F) A "my", "our" or "state" declaration was found within another declaration,
1291such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1292
6df41af2
GS
1293=item Can't "redo" outside a loop block
1294
1295(F) A "redo" statement was executed to restart the current block, but
1296there isn't a current block. Note that an "if" or "else" block doesn't
1297count as a "loopish" block, as doesn't a block given to sort(), map()
1298or grep(). You can usually double the curlies to get the same effect
1299though, because the inner curlies will be considered a block that
1300loops once. See L<perlfunc/redo>.
1301
64977eb6 1302=item Can't remove %s: %s, skipping file
10f9c03d 1303
be771a83
GS
1304(S inplace) You requested an inplace edit without creating a backup
1305file. Perl was unable to remove the original file to replace it with
1306the modified file. The file was left unmodified.
10f9c03d 1307
a0d0e21e
LW
1308=item Can't rename %s to %s: %s, skipping file
1309
e476b1b5 1310(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1311probably because you don't have write permission to the directory.
a0d0e21e 1312
748a9306
LW
1313=item Can't reopen input pipe (name: %s) in binary mode
1314
be771a83
GS
1315(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1316to reopen it to accept binary data. Alas, it failed.
748a9306 1317
9415f659
KW
1318=item Can't represent character for Ox%X on this platform
1319
1320(F) There is a hard limit to how big a character code point can be due
1321to the fundamental properties of UTF-8, especially on EBCDIC
1322platforms. The given code point exceeds that. The only work-around is
1323to not use such a large code point.
1324
4f12ec0e
FC
1325=item Can't reset %ENV on this system
1326
1327(F) You called C<reset('E')> or similar, which tried to reset
1328all variables in the current package beginning with "E". In
1329the main package, that includes %ENV. Resetting %ENV is not
1330supported on some systems, notably VMS.
1331
fe13d51d 1332=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1333
1fa582fa
FC
1334(F)(P) Error resolving overloading specified by a method name (as
1335opposed to a subroutine reference): no such method callable via the
1336package. If the method name is C<???>, this is an internal error.
6df41af2 1337
cd06dffe
GS
1338=item Can't return %s from lvalue subroutine
1339
be771a83
GS
1340(F) Perl detected an attempt to return illegal lvalues (such as
1341temporary or readonly values) from a subroutine used as an lvalue. This
1342is not allowed.
cd06dffe 1343
96ebfdd7
RK
1344=item Can't return outside a subroutine
1345
1346(F) The return statement was executed in mainline code, that is, where
1347there was no subroutine call to return out of. See L<perlsub>.
1348
78f9721b
SM
1349=item Can't return %s to lvalue scalar context
1350
6903afa2
FC
1351(F) You tried to return a complete array or hash from an lvalue
1352subroutine, but you called the subroutine in a way that made Perl
1353think you meant to return only one value. You probably meant to
1354write parentheses around the call to the subroutine, which tell
1355Perl that the call should be in list context.
78f9721b 1356
a0d0e21e
LW
1357=item Can't stat script "%s"
1358
be771a83
GS
1359(P) For some reason you can't fstat() the script even though you have it
1360open already. Bizarre.
a0d0e21e 1361
a0d0e21e
LW
1362=item Can't take log of %g
1363
fb73857a 1364(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1365negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1366standard with Perl, though, if you really want to do that for the
1367negative numbers.
a0d0e21e
LW
1368
1369=item Can't take sqrt of %g
1370
1371(F) For ordinary real numbers, you can't take the square root of a
fb73857a 1372negative number. There's a Math::Complex package that comes standard
1373with Perl, though, if you really want to do that.
a0d0e21e
LW
1374
1375=item Can't undef active subroutine
1376
1377(F) You can't undefine a routine that's currently running. You can,
1378however, redefine it while it's running, and you can even undef the
1379redefined subroutine while the old routine is running. Go figure.
1380
c81225bc 1381=item Can't upgrade %s (%d) to %d
a0d0e21e 1382
be771a83
GS
1383(P) The internal sv_upgrade routine adds "members" to an SV, making it
1384into a more specialized kind of SV. The top several SV types are so
1385specialized, however, that they cannot be interconverted. This message
1386indicates that such a conversion was attempted.
a0d0e21e 1387
6651ba0b
FC
1388=item Can't use '%c' after -mname
1389
1390(F) You tried to call perl with the B<-m> switch, but you put something
1391other than "=" after the module name.
1392
1f1ec7b5
KW
1393=item Can't use a hash as a reference
1394
1395(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1396C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1397<= 5.22.0 used to allow this syntax, but shouldn't
1398have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1399
1400=item Can't use an array as a reference
1401
1402(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1403C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1404used to allow this syntax, but shouldn't have. This
1405was deprecated in perl 5.6.1.
1f1ec7b5 1406
1db89ea5
BS
1407=item Can't use anonymous symbol table for method lookup
1408
e27ad1f2 1409(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1410table that doesn't have a name. Symbol tables can become anonymous
1411for example by undefining stashes: C<undef %Some::Package::>.
1412
96ebfdd7
RK
1413=item Can't use an undefined value as %s reference
1414
1415(F) A value used as either a hard reference or a symbolic reference must
1416be a defined value. This helps to delurk some insidious errors.
1417
6df41af2
GS
1418=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1419
be771a83
GS
1420(F) Only hard references are allowed by "strict refs". Symbolic
1421references are disallowed. See L<perlref>.
6df41af2 1422
90b75b61 1423=item Can't use %! because Errno.pm is not available
1d2dff63 1424
20561843 1425(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1426Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1427provide symbolic names for C<$!> errno values.
1428
1109a392
MHM
1429=item Can't use both '<' and '>' after type '%c' in %s
1430
1431(F) A type cannot be forced to have both big-endian and little-endian
1432byte-order at the same time, so this combination of modifiers is not
1433allowed. See L<perlfunc/pack>.
1434
e35475de
KW
1435=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1436
1437(F) defined() is not useful on arrays because it
1438checks for an undefined I<scalar> value. If you want to see if the
1439array is empty, just use C<if (@array) { # not empty }> for example.
1440
1441=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1442
1443(F) C<defined()> is not usually right on hashes.
1444
1445Although C<defined %hash> is false on a plain not-yet-used hash, it
1446becomes true in several non-obvious circumstances, including iterators,
1447weak references, stash names, even remaining true after C<undef %hash>.
1448These things make C<defined %hash> fairly useless in practice, so it now
1449generates a fatal error.
1450
1451If a check for non-empty is what you wanted then just put it in boolean
1452context (see L<perldata/Scalar values>):
1453
1454 if (%hash) {
1455 # not empty
1456 }
1457
1458If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1459variable exists then that's never really been reliable, and isn't
1460a good way to enquire about the features of a package, or whether
1461it's loaded, etc.
1462
6df41af2
GS
1463=item Can't use %s for loop variable
1464
c1f06047 1465(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1466
aab6a793 1467=item Can't use global %s in "%s"
6df41af2 1468
be771a83
GS
1469(F) You tried to declare a magical variable as a lexical variable. This
1470is not allowed, because the magic can be tied to only one location
1471(namely the global variable) and it would be incredibly confusing to
1472have variables in your program that looked like magical variables but
6df41af2
GS
1473weren't.
1474
6d3b25aa
RGS
1475=item Can't use '%c' in a group with different byte-order in %s
1476
1477(F) You attempted to force a different byte-order on a type
1478that is already inside a group with a byte-order modifier.
1479For example you cannot force little-endianness on a type that
1480is inside a big-endian group.
1481
c07a80fd 1482=item Can't use "my %s" in sort comparison
1483
1484(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1485You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd 1486and the variable had earlier been declared as a lexical variable.
1487Either qualify the sort variable with the package name, or rename the
1488lexical variable.
1489
a0d0e21e
LW
1490=item Can't use %s ref as %s ref
1491
1492(F) You've mixed up your reference types. You have to dereference a
1493reference of the type needed. You can use the ref() function to
1494test the type of the reference, if need be.
1495
748a9306 1496=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1497
5e634d20
FC
1498=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1499
b41bf23f
FC
1500(F) You've told Perl to dereference a string, something which
1501C<use strict> blocks to prevent it happening accidentally. See
1502L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1503in a double-quoted string immediately before interpolating a variable,
1504for example in C<"user @$twitter_id">, which says to treat the contents
1505of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1506symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1507
748a9306
LW
1508=item Can't use subscript on %s
1509
1510(F) The compiler tried to interpret a bracketed expression as a
1511subscript. But to the left of the brackets was an expression that
209e7cf1 1512didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1513
6df41af2
GS
1514=item Can't use \%c to mean $%c in expression
1515
75b44862
GS
1516(W syntax) In an ordinary expression, backslash is a unary operator that
1517creates a reference to its argument. The use of backslash to indicate a
1518backreference to a matched substring is valid only as part of a regular
be771a83
GS
1519expression pattern. Trying to do this in ordinary Perl code produces a
1520value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1521instead.
6df41af2 1522
810b8aa5
GS
1523=item Can't weaken a nonreference
1524
1525(F) You attempted to weaken something that was not a reference. Only
1526references can be weakened.
1527
fc7debfb
FC
1528=item Can't "when" outside a topicalizer
1529
1530(F) You have used a when() block that is neither inside a C<foreach>
1531loop nor a C<given> block. (Note that this error is issued on exit
1532from the C<when> block, so you won't get the error if the match fails,
1533or if you use an explicit C<continue>.)
1534
5f05dabc 1535=item Can't x= to read-only value
a0d0e21e 1536
be771a83
GS
1537(F) You tried to repeat a constant value (often the undefined value)
1538with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1539Perhaps you need to copy the value to a temporary, and repeat that.
1540
a04e6aad 1541=item Character following "\c" must be printable ASCII
f9d13529 1542
7357bd17 1543(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1544
727b6379 1545Note that ASCII characters that don't map to control characters are
7357bd17 1546discouraged, and will generate the warning (when enabled)
727b6379 1547L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1548
163a633c
KW
1549=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1550
1551(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1552specified something that isn't a legal Unicode property name. Most
1553Unicode properties are specified by C<\p{...}>. But if the name is a
1554single character one, the braces may be omitted.
1555
f337b084 1556=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1557
1558(W pack) You said
1559
1560 pack("C", $x)
1561
1562where $x is either less than 0 or more than 255; the C<"C"> format is
1563only for encoding native operating system characters (ASCII, EBCDIC,
1564and so on) and not for Unicode characters, so Perl behaved as if you meant
1565
1566 pack("C", $x & 255)
1567
1568If you actually want to pack Unicode codepoints, use the C<"U"> format
1569instead.
1570
f337b084 1571=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1572
1573(W pack) You said
1574
1575 pack("c", $x)
1576
1577where $x is either less than -128 or more than 127; the C<"c"> format
1578is only for encoding native operating system characters (ASCII, EBCDIC,
1579and so on) and not for Unicode characters, so Perl behaved as if you meant
1580
1581 pack("c", $x & 255);
1582
1583If you actually want to pack Unicode codepoints, use the C<"U"> format
1584instead.
1585
f337b084
TH
1586=item Character in '%c' format wrapped in unpack
1587
1588(W unpack) You tried something like
1589
1590 unpack("H", "\x{2a1}")
1591
1a147d38 1592where the format expects to process a byte (a character with a value
6903afa2
FC
1593below 256), but a higher value was provided instead. Perl uses the
1594value modulus 256 instead, as if you had provided:
f337b084
TH
1595
1596 unpack("H", "\x{a1}")
1597
5a25739d
FC
1598=item Character in 'W' format wrapped in pack
1599
1600(W pack) You said
1601
1602 pack("U0W", $x)
1603
1604where $x is either less than 0 or more than 255. However, C<U0>-mode
1605expects all values to fall in the interval [0, 255], so Perl behaved
1606as if you meant:
1607
1608 pack("U0W", $x & 255)
1609
f337b084
TH
1610=item Character(s) in '%c' format wrapped in pack
1611
1612(W pack) You tried something like
1613
1614 pack("u", "\x{1f3}b")
1615
1a147d38 1616where the format expects to process a sequence of bytes (character with a
6903afa2 1617value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1618uses the character values modulus 256 instead, as if you had provided:
1619
1620 pack("u", "\x{f3}b")
1621
1622=item Character(s) in '%c' format wrapped in unpack
1623
1624(W unpack) You tried something like
1625
1626 unpack("s", "\x{1f3}b")
1627
1a147d38 1628where the format expects to process a sequence of bytes (character with a
6903afa2 1629value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1630uses the character values modulus 256 instead, as if you had provided:
1631
1632 unpack("s", "\x{f3}b")
1633
f51551f7
FC
1634=item charnames alias definitions may not contain a sequence of multiple spaces
1635
1636(F) You defined a character name which had multiple space characters
1637in a row. Change them to single spaces. Usually these names are
1638defined in the C<:alias> import argument to C<use charnames>, but they
1639could be defined by a translator installed into C<$^H{charnames}>. See
1640L<charnames/CUSTOM ALIASES>.
1641
1642=item charnames alias definitions may not contain trailing white-space
1643
1644(F) You defined a character name which ended in a space
1645character. Remove the trailing space(s). Usually these names are
1646defined in the C<:alias> import argument to C<use charnames>, but they
1647could be defined by a translator installed into C<$^H{charnames}>.
1648See L<charnames/CUSTOM ALIASES>.
1649
60121127
TC
1650=item chdir() on unopened filehandle %s
1651
1652(W unopened) You tried chdir() on a filehandle that was never opened.
1653
f866a7cd
FC
1654=item "\c%c" is more clearly written simply as "%s"
1655
1656(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1657non-printable characters. You used it for a printable one, which
1658is better written as simply itself, perhaps preceded by a backslash
1659for non-word characters. Doing it the way you did is not portable
1660between ASCII and EBCDIC platforms.
f866a7cd 1661
6651ba0b
FC
1662=item Cloning substitution context is unimplemented
1663
1664(F) Creating a new thread inside the C<s///> operator is not supported.
1665
abc7ecad
SP
1666=item closedir() attempted on invalid dirhandle %s
1667
1668(W io) The dirhandle you tried to close is either closed or not really
1669a dirhandle. Check your control flow.
1670
5a25739d
FC
1671=item close() on unopened filehandle %s
1672
1673(W unopened) You tried to close a filehandle that was never opened.
1674
541ed3a9
FC
1675=item Closure prototype called
1676
1677(F) If a closure has attributes, the subroutine passed to an attribute
1678handler is the prototype that is cloned when a new closure is created.
1679This subroutine cannot be called.
1680
74d1b2e4
FC
1681=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1682
1683(F) The \C character class used to allow a match of single byte
1684within a multi-byte utf-8 character, but was removed in v5.24 as
1685it broke encapsulation and its implementation was extremely buggy.
1686If you really need to process the individual bytes, you probably
1687want to convert your string to one where each underlying byte is
1688stored as a character, with utf8::encode().
1689
49704364
WL
1690=item Code missing after '/'
1691
6903afa2
FC
1692(F) You had a (sub-)template that ends with a '/'. There must be
1693another template code following the slash. See L<perlfunc/pack>.
49704364 1694
c0236afe
KW
1695=item Code point 0x%X is not Unicode, and not portable
1696
1697(S non_unicode) You had a code point that has never been in any
1698standard, so it is likely that languages other than Perl will NOT
1699understand it. At one time, it was legal in some standards to have code
1700points up to 0x7FFF_FFFF, but not higher, and this code point is higher.
1701
1702Acceptance of these code points is a Perl extension, and you should
1703expect that nothing other than Perl can handle them; Perl itself on
1704EBCDIC platforms before v5.24 does not handle them.
1705
1706Code points above 0xFFFF_FFFF require larger than a 32 bit word.
1707
1708Perl also makes no guarantees that the representation of these code
1709points won't change at some point in the future, say when machines
1710become available that have larger than a 64-bit word. At that time,
1711files written by an older Perl would require conversion before being
1712readable by a newer Perl.
1713
5a25739d
FC
1714=item Code point 0x%X is not Unicode, may not be portable
1715
2d88a86a 1716(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1717of U+10FFFF.
1718
c0236afe
KW
1719Perl allows strings to contain a superset of Unicode code points, but
1720these may not be accepted by other languages/systems. Further, even if
1721these languages/systems accept these large code points, they may have
1722chosen a different representation for them than the UTF-8-like one that
1723Perl has, which would mean files are not exchangeable between them and
1724Perl.
1725
1726On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1727representation in Perl v5.24 than before, so any file containing these
1728that was written before that version will require conversion before
1729being readable by a later Perl.
0876b9a0 1730
6df41af2
GS
1731=item %s: Command not found
1732
a892b81a 1733(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1734instead of Perl. Check the #! line, or manually feed your script into
1735Perl yourself. The #! line at the top of your file could look like
8f721816 1736
3bcfc7b3
LM
1737 #!/usr/bin/perl
1738
1739=item %s: command not found
1740
1741(A) You've accidentally run your script through B<bash> or another shell
1742instead of Perl. Check the #! line, or manually feed your script into
1743Perl yourself. The #! line at the top of your file could look like
1744
1745 #!/usr/bin/perl
1746
1747=item %s: command not found: %s
1748
1749(A) You've accidentally run your script through B<zsh> or another shell
1750instead of Perl. Check the #! line, or manually feed your script into
1751Perl yourself. The #! line at the top of your file could look like
1752
1753 #!/usr/bin/perl
6df41af2 1754
7a2e2cd6 1755=item Compilation failed in require
1756
1757(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1758Perl uses this generic message when none of the errors that it
1759encountered were severe enough to halt compilation immediately.
7a2e2cd6 1760
c3464db5
DD
1761=item Complex regular subexpression recursion limit (%d) exceeded
1762
be771a83
GS
1763(W regexp) The regular expression engine uses recursion in complex
1764situations where back-tracking is required. Recursion depth is limited
1765to 32766, or perhaps less in architectures where the stack cannot grow
1766arbitrarily. ("Simple" and "medium" situations are handled without
1767recursion and are not subject to a limit.) Try shortening the string
1768under examination; looping in Perl code (e.g. with C<while>) rather than
1769in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1770that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1771on I<Mastering Regular Expressions>.)
c3464db5 1772
69282e91 1773=item connect() on closed socket %s
a0d0e21e 1774
be771a83
GS
1775(W closed) You tried to do a connect on a closed socket. Did you forget
1776to check the return value of your socket() call? See
1777L<perlfunc/connect>.
a0d0e21e 1778
e21e7c6a
FC
1779=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1780
1781(F) The subroutine registered to handle constant overloading
1782(see L<overload>) or a custom charnames handler (see
1783L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1784
1785=item Constant(%s): $^H{%s} is not defined
1786
1787(F) The parser found inconsistencies while attempting to define an
1788overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1789L<overload> pragma?
e21e7c6a 1790
779c5bc9
GS
1791=item Constant is not %s reference
1792
1793(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1794is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1795The message indicates the type of reference that was expected. This
be771a83 1796usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1797See L<perlsub/"Constant Functions"> and L<constant>.
1798
0ac016fc
FC
1799=item Constants from lexical variables potentially modified elsewhere are
1800deprecated
1801
1802(D deprecated) You wrote something like
1803
1804 my $var;
1805 $sub = sub () { $var };
1806
1807but $var is referenced elsewhere and could be modified after the C<sub>
1808expression is evaluated. Either it is explicitly modified elsewhere
1809(C<$var = 3>) or it is passed to a subroutine or to an operator like
1810C<printf> or C<map>, which may or may not modify the variable.
1811
1812Traditionally, Perl has captured the value of the variable at that
1813point and turned the subroutine into a constant eligible for inlining.
1814In those cases where the variable can be modified elsewhere, this
1815breaks the behavior of closures, in which the subroutine captures
1816the variable itself, rather than its value, so future changes to the
1817variable are reflected in the subroutine's return value.
1818
1819This usage is deprecated, because the behavior is likely to change
1820in a future version of Perl.
1821
1822If you intended for the subroutine to be eligible for inlining, then
1823make sure the variable is not referenced elsewhere, possibly by
1824copying it:
1825
1826 my $var2 = $var;
1827 $sub = sub () { $var2 };
1828
1829If you do want this subroutine to be a closure that reflects future
1830changes to the variable that it closes over, add an explicit C<return>:
1831
1832 my $var;
1833 $sub = sub () { return $var };
1834
4cee8e80
CS
1835=item Constant subroutine %s redefined
1836
aeb94125
FC
1837(W redefine)(S) You redefined a subroutine which had previously
1838been eligible for inlining. See L<perlsub/"Constant Functions">
1839for commentary and workarounds.
4cee8e80 1840
9607fc9c 1841=item Constant subroutine %s undefined
1842
be771a83
GS
1843(W misc) You undefined a subroutine which had previously been eligible
1844for inlining. See L<perlsub/"Constant Functions"> for commentary and
1845workarounds.
9607fc9c 1846
5a25739d
FC
1847=item Constant(%s) unknown
1848
1849(F) The parser found inconsistencies either while attempting
1850to define an overloaded constant, or when trying to find the
1851character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1852forgot to load the corresponding L<overload> pragma?
5a25739d 1853
4a873d7a
FC
1854=item :const is experimental
1855
1856(S experimental::const_attr) The "const" attribute is experimental.
1857If you want to use the feature, disable the warning with C<no warnings
1858'experimental::const_attr'>, but know that in doing so you are taking
1859the risk that your code may break in a future Perl version.
1860
b77472f9
FC
1861=item :const is not permitted on named subroutines
1862
1863(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1864its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1865not cloned like this, so the attribute does not make sense on them.
1866
e7ea3e70
IZ
1867=item Copy method did not return a reference
1868
6903afa2 1869(F) The method which overloads "=" is buggy. See
13a2d996 1870L<overload/Copy Constructor>.
e7ea3e70 1871
4aaa4757
FC
1872=item &CORE::%s cannot be called directly
1873
1874(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1875with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1876in this package cannot yet be called that way, but must be
1877called as barewords. Something like this will work:
1878
1879 BEGIN { *shove = \&CORE::push; }
1880 shove @array, 1,2,3; # pushes on to @array
1881
6798c92b
GS
1882=item CORE::%s is not a keyword
1883
1884(F) The CORE:: namespace is reserved for Perl keywords.
1885
675fa9ff
FC
1886=item Corrupted regexp opcode %d > %d
1887
1888(P) This is either an error in Perl, or, if you're using
1889one, your L<custom regular expression engine|perlreapi>. If not the
1890latter, report the problem through the L<perlbug> utility.
1891
a0d0e21e
LW
1892=item corrupted regexp pointers
1893
1894(P) The regular expression engine got confused by what the regular
1895expression compiler gave it.
1896
1897=item corrupted regexp program
1898
be771a83
GS
1899(P) The regular expression engine got passed a regexp program without a
1900valid magic number.
a0d0e21e 1901
de42a5a9 1902=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1903
1904(P) The malloc package that comes with Perl had an internal failure.
1905
49704364
WL
1906=item Count after length/code in unpack
1907
1908(F) You had an unpack template indicating a counted-length string, but
1909you have also specified an explicit size for the string. See
1910L<perlfunc/pack>.
1911
3f645a4e
FC
1912=item Declaring references is experimental
1913
1914(S experimental::declared_refs) This warning is emitted if you use
1915a reference constructor on the right-hand side of C<my>, C<state>, C<our>, or
1916C<local>. Simply suppress the warning if you want to use the feature, but
1917know that in doing so you are taking the risk of using an experimental
1918feature which may change or be removed in a future Perl version:
1919
1920 no warnings "experimental::declared_refs";
1921 use feature "declared_refs";
1922 $fooref = my \$foo;
1923
f2cccb4c
KW
1924=for comment
1925The following are used in lib/diagnostics.t for testing two =items that
1926share the same description. Changes here need to be propagated to there
1927
6651ba0b
FC
1928=item Deep recursion on anonymous subroutine
1929
a0d0e21e
LW
1930=item Deep recursion on subroutine "%s"
1931
be771a83
GS
1932(W recursion) This subroutine has called itself (directly or indirectly)
1933100 times more than it has returned. This probably indicates an
1934infinite recursion, unless you're writing strange benchmark programs, in
1935which case it indicates something else.
a0d0e21e 1936
aad1d01f
NC
1937This threshold can be changed from 100, by recompiling the F<perl> binary,
1938setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1939
e0e4a6e3
FC
1940=item (?(DEFINE)....) does not allow branches in regex; marked by
1941S<<-- HERE> in m/%s/
bcb95744 1942
6903afa2 1943(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1944most likely cause of this error is that you left out a parenthesis inside
1945of the C<....> part.
1946
6e8a73f2 1947The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1948discovered.
1949
62658f4d
PM
1950=item %s defines neither package nor VERSION--version check failed
1951
1952(F) You said something like "use Module 42" but in the Module file
1953there are neither package declarations nor a C<$VERSION>.
1954
36447869
FC
1955=item delete argument is index/value array slice, use array slice
1956
1957(F) You used index/value array slice syntax (C<%array[...]>) as
1958the argument to C<delete>. You probably meant C<@array[...]> with
1959an @ symbol instead.
1960
1961=item delete argument is key/value hash slice, use hash slice
1962
1963(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1964C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1965
0ffcbc25
FC
1966=item delete argument is not a HASH or ARRAY element or slice
1967
4a0af295 1968(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1969such as:
1970
1971 $foo{$bar}
1972 $ref->{"susie"}[12]
1973
1974or a hash or array slice, such as:
1975
1976 @foo[$bar, $baz, $xyzzy]
1977 @{$ref->[12]}{"susie", "queue"}
1978
fc36a67e 1979=item Delimiter for here document is too long
1980
be771a83
GS
1981(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1982long for Perl to handle. You have to be seriously twisted to write code
1983that triggers this error.
fc36a67e 1984
6d3b25aa
RGS
1985=item Deprecated use of my() in false conditional
1986
fa816bf3
FC
1987(D deprecated) You used a declaration similar to C<my $x if 0>. There
1988has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1989not to be cleared at scope exit when its declaration includes a false
6903afa2 1990conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1991static variable. Since we intend to fix this bug, we don't want people
6903afa2 1992relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1993declaring the variable in a separate block outside the function, eg
36fb85f3 1994
6d3b25aa
RGS
1995 sub f { my $x if 0; return $x++ }
1996
1997becomes
1998
1999 { my $x; sub f { return $x++ } }
2000
ea9d9ebc 2001Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 2002lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
2003
2004 sub f { state $x; return $x++ }
2005
500ab966
RGS
2006=item DESTROY created new reference to dead object '%s'
2007
2008(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
2009just being DESTROYed. Perl is confused, and prefers to abort rather
2010than to create a dangling reference.
500ab966 2011
3cdd684c
TP
2012=item Did not produce a valid header
2013
3de20fbe 2014See L</500 Server error>.
3cdd684c 2015
6df41af2
GS
2016=item %s did not return a true value
2017
2018(F) A required (or used) file must return a true value to indicate that
2019it compiled correctly and ran its initialization code correctly. It's
2020traditional to end such a file with a "1;", though any true value would
2021do. See L<perlfunc/require>.
2022
cc507455 2023=item (Did you mean &%s instead?)
4633a7c4 2024
413ff9f6
FC
2025(W misc) You probably referred to an imported subroutine &FOO as $FOO or
2026some such.
4633a7c4 2027
cc507455 2028=item (Did you mean "local" instead of "our"?)
33633739 2029
be771a83
GS
2030(W misc) Remember that "our" does not localize the declared global
2031variable. You have declared it again in the same lexical scope, which
2032seems superfluous.
33633739 2033
cc507455 2034=item (Did you mean $ or @ instead of %?)
a0d0e21e 2035
be771a83
GS
2036(W) You probably said %hash{$key} when you meant $hash{$key} or
2037@hash{@keys}. On the other hand, maybe you just meant %hash and got
2038carried away.
748a9306 2039
7e1af8bc 2040=item Died
5f05dabc 2041
2042(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 2043you called it with no args and C<$@> was empty.
5f05dabc 2044
3cdd684c
TP
2045=item Document contains no data
2046
3de20fbe 2047See L</500 Server error>.
3cdd684c 2048
62658f4d
PM
2049=item %s does not define %s::VERSION--version check failed
2050
2051(F) You said something like "use Module 42" but the Module did not
943fc58e 2052define a C<$VERSION>.
62658f4d 2053
49704364
WL
2054=item '/' does not take a repeat count
2055
2056(F) You cannot put a repeat count of any kind right after the '/' code.
2057See L<perlfunc/pack>.
2058
95cb0d72
FC
2059=item Don't know how to get file name
2060
2061(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
2062somehow called on another platform. This should not happen.
2063
4021c788 2064=item Don't know how to handle magic of type \%o
a0d0e21e
LW
2065
2066(P) The internal handling of magical variables has been cursed.
2067
2068=item do_study: out of memory
2069
2070(P) This should have been caught by safemalloc() instead.
2071
6df41af2
GS
2072=item (Do you need to predeclare %s?)
2073
56da5a46
RGS
2074(S syntax) This is an educated guess made in conjunction with the message
2075"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
2076name is being referenced that hasn't been declared yet. This may be
2077because of ordering problems in your file, or because of a missing
be771a83
GS
2078"sub", "package", "require", or "use" statement. If you're referencing
2079something that isn't defined yet, you don't actually have to define the
2080subroutine or package before the current location. You can use an empty
2081"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 2082
ac206dc8
RGS
2083=item dump() better written as CORE::dump()
2084
2085(W misc) You used the obsolescent C<dump()> built-in function, without fully
2086qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
2087
84d78eb7
YO
2088=item dump is not supported
2089
2090(F) Your machine doesn't support dump/undump.
2091
a0d0e21e
LW
2092=item Duplicate free() ignored
2093
be771a83
GS
2094(S malloc) An internal routine called free() on something that had
2095already been freed.
a0d0e21e 2096
1109a392
MHM
2097=item Duplicate modifier '%c' after '%c' in %s
2098
35f0cd76
FC
2099(W unpack) You have applied the same modifier more than once after a
2100type in a pack template. See L<perlfunc/pack>.
1109a392 2101
4633a7c4
LW
2102=item elseif should be elsif
2103
fa816bf3
FC
2104(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2105it's ugly. Your code will be interpreted as an attempt to call a method
2106named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2107unlikely to be what you want.
2108
c30c479a
KW
2109=item Empty \%c in regex; marked by S<<-- HERE> in m/%s/
2110
e0e4a6e3 2111=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2112
af6f566e 2113(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 2114described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 2115a regular expression without specifying the property name.
ab13f0c7 2116
a15a3d9b
FC
2117=item ${^ENCODING} is no longer supported
2118
2119(D deprecated) The special variable C<${^ENCODING}>, formerly used to implement
2120the C<encoding> pragma, is no longer supported as of Perl 5.26.0.
2121
85ab1d1d 2122=item entering effective %s failed
5ff3f7a4 2123
85ab1d1d 2124(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2125effective uids or gids failed.
2126
c038024b
RGS
2127=item %ENV is aliased to %s
2128
2129(F) You're running under taint mode, and the C<%ENV> variable has been
2130aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2131program's environment. This is potentially insecure.
c038024b 2132
748a9306
LW
2133=item Error converting file specification %s
2134
5f05dabc 2135(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2136specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2137single form when it must operate on them directly. Either you've passed
2138an invalid file specification to Perl, or you've found a case the
2139conversion routines don't handle. Drat.
748a9306 2140
ad19ef22 2141=item Eval-group in insecure regular expression
e4d48cc9 2142
be771a83
GS
2143(F) Perl detected tainted data when trying to compile a regular
2144expression that contains the C<(?{ ... })> zero-width assertion, which
2145is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2146
ad19ef22 2147=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2148
be771a83
GS
2149(F) Perl tried to compile a regular expression containing the
2150C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2151pattern contains interpolated values. Since that is a security risk,
2152it is not allowed. If you insist, you may still do this by using the
2153C<re 'eval'> pragma or by explicitly building the pattern from an
2154interpolated string at run time and using that in an eval(). See
2155L<perlre/(?{ code })>.
e4d48cc9 2156
ad19ef22 2157=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2158
be771a83
GS
2159(F) A regular expression contained the C<(?{ ... })> zero-width
2160assertion, but that construct is only allowed when the C<use re 'eval'>
2161pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2162
e0e4a6e3
FC
2163=item EVAL without pos change exceeded limit in regex; marked by
2164S<<-- HERE> in m/%s/
1a147d38
YO
2165
2166(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2167any text. Restructure the pattern so that text is consumed.
1a147d38 2168
6e8a73f2 2169The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2170discovered.
2171
fc36a67e 2172=item Excessively long <> operator
2173
2174(F) The contents of a <> operator may not exceed the maximum size of a
2175Perl identifier. If you're just trying to glob a long list of
2176filenames, try using the glob() operator, or put the filenames into a
2177variable and glob that.
2178
ed9aa3b7
SG
2179=item exec? I'm not *that* kind of operating system
2180
af8bb25a 2181(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2182OS. See L<perlport>.
ed9aa3b7 2183
fe13d51d 2184=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
2185
2186(F) The final summary message when a Perl compilation fails.
2187
0ffcbc25
FC
2188=item exists argument is not a HASH or ARRAY element or a subroutine
2189
4a0af295 2190(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2191subroutine with an ampersand, such as:
2192
2193 $foo{$bar}
2194 $ref->{"susie"}[12]
2195 &do_something
2196
2197=item exists argument is not a subroutine name
2198
ccfc2567
FC
2199(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2200and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2201
a0d0e21e
LW
2202=item Exiting eval via %s
2203
be771a83
GS
2204(W exiting) You are exiting an eval by unconventional means, such as a
2205goto, or a loop control statement.
e476b1b5
GS
2206
2207=item Exiting format via %s
2208
9a2ff54b 2209(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2210goto, or a loop control statement.
a0d0e21e 2211
0a753a76 2212=item Exiting pseudo-block via %s
2213
be771a83
GS
2214(W exiting) You are exiting a rather special block construct (like a
2215sort block or subroutine) by unconventional means, such as a goto, or a
2216loop control statement. See L<perlfunc/sort>.
0a753a76 2217
a0d0e21e
LW
2218=item Exiting subroutine via %s
2219
be771a83
GS
2220(W exiting) You are exiting a subroutine by unconventional means, such
2221as a goto, or a loop control statement.
a0d0e21e
LW
2222
2223=item Exiting substitution via %s
2224
be771a83
GS
2225(W exiting) You are exiting a substitution by unconventional means, such
2226as a return, a goto, or a loop control statement.
a0d0e21e 2227
e0e4a6e3 2228=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2229
675fa9ff 2230(F) You wrote something like
c608e803
KW
2231
2232 (?13
2233
2234to denote a capturing group of the form
2235L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2236but omitted the C<")">.
2237
e0e4a6e3 2238=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2239
8b6fbf55
FC
2240(F) The C<(?[...])> extended character class regular expression construct
2241only allows character classes (including character class escapes like
2242C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2243containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2244This allows a regular expression containing just C<(?[...])> to be
2245interpolated. If you see this error message, then you probably
2246have some other C<(?...)> construct inside your character class. See
2247L<perlrecharclass/Extended Bracketed Character Classes>.
2248
baabe3fb 2249=item Experimental aliasing via reference not enabled
1f8155a2 2250
baabe3fb 2251(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2252
baabe3fb
FC
2253 no warnings "experimental::refaliasing";
2254 use feature "refaliasing";
1f8155a2
FC
2255 \$x = \$y;
2256
74d1b2e4
FC
2257=item Experimental %s on scalar is now forbidden
2258
2259(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2260C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called with a
2261scalar argument. This experiment is considered unsuccessful, and
2262has been removed. The C<postderef> feature may meet your needs better.
2263
30d9c59b
Z
2264=item Experimental subroutine signatures not enabled
2265
2266(F) To use subroutine signatures, you must first enable them:
2267
caa35032 2268 no warnings "experimental::signatures";
30d9c59b
Z
2269 use feature "signatures";
2270 sub foo ($left, $right) { ... }
2271
7b8d334a
GS
2272=item Explicit blessing to '' (assuming package main)
2273
be771a83
GS
2274(W misc) You are blessing a reference to a zero length string. This has
2275the effect of blessing the reference into the package main. This is
2276usually not what you want. Consider providing a default target package,
2277e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2278
6df41af2
GS
2279=item %s: Expression syntax
2280
be771a83
GS
2281(A) You've accidentally run your script through B<csh> instead of Perl.
2282Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2283
2284=item %s failed--call queue aborted
2285
3c10abe3
AG
2286(F) An untrapped exception was raised while executing a UNITCHECK,
2287CHECK, INIT, or END subroutine. Processing of the remainder of the
2288queue of such routines has been prematurely ended.
6df41af2 2289
502aca56
TC
2290=item Failed to close in-place edit file %s: %s
2291
2292(F) Closing an output file from in-place editing, as with the C<-i>
2293command-line switch, failed.
2294
e0e4a6e3 2295=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2296
98d31c73 2297(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2298character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2299in your false range is interpreted as a literal "-". In a C<(?[...])>
2300construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2301the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2302the problem was discovered. See L<perlre>.
73b437c8 2303
1b1ee2ef 2304=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2305
be771a83
GS
2306(P) An error peculiar to VMS. Something untoward happened in a VMS
2307system service or RTL routine; Perl's exit status should provide more
2308details. The filename in "at %s" and the line number in "line %d" tell
2309you which section of the Perl source code is distressed.
a0d0e21e
LW
2310
2311=item fcntl is not implemented
2312
2313(F) Your machine apparently doesn't implement fcntl(). What is this, a
2314PDP-11 or something?
2315
22846ab4
AB
2316=item FETCHSIZE returned a negative value
2317
2318(F) A tied array claimed to have a negative number of elements, which
2319is not possible.
2320
f337b084
TH
2321=item Field too wide in 'u' format in pack
2322
d8b5cc61 2323(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2324which can't encode values above 63. So there is no point in asking for
2325a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2326C<u63> as the format.
f337b084 2327
af8c498a 2328=item Filehandle %s opened only for input
a0d0e21e 2329
6c8d78fb
HS
2330(W io) You tried to write on a read-only filehandle. If you intended
2331it to be a read-write filehandle, you needed to open it with "+<" or
2332"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2333write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2334
af8c498a 2335=item Filehandle %s opened only for output
a0d0e21e 2336
6c8d78fb
HS
2337(W io) You tried to read from a filehandle opened only for writing, If
2338you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2339with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2340read from the file, use "<". See L<perlfunc/open>. Another possibility
2341is that you attempted to open filedescriptor 0 (also known as STDIN) for
2342output (maybe you closed STDIN earlier?).
97828cef
RGS
2343
2344=item Filehandle %s reopened as %s only for input
2345
2346(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2347as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2348previously.
2349
2350=item Filehandle STDIN reopened as %s only for output
2351
2352(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2353as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2354
2355=item Final $ should be \$ or $name
2356
2357(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2358a literal dollar sign, or was meant to introduce a variable name that
2359happens to be missing. So you have to put either the backslash or the
2360name.
a0d0e21e 2361
56e90b21
GS
2362=item flock() on closed filehandle %s
2363
be771a83 2364(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2365some time before now. Check your control flow. flock() operates on
be771a83
GS
2366filehandles. Are you attempting to call flock() on a dirhandle by the
2367same name?
56e90b21 2368
6df41af2
GS
2369=item Format not terminated
2370
2371(F) A format must be terminated by a line with a solitary dot. Perl got
2372to the end of your file without finding such a line.
2373
a0d0e21e
LW
2374=item Format %s redefined
2375
e476b1b5 2376(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2377
2378 {
271595cc 2379 no warnings 'redefine';
a0d0e21e
LW
2380 eval "format NAME =...";
2381 }
2382
a0d0e21e
LW
2383=item Found = in conditional, should be ==
2384
e476b1b5 2385(W syntax) You said
a0d0e21e
LW
2386
2387 if ($foo = 123)
2388
2389when you meant
2390
2391 if ($foo == 123)
2392
2393(or something like that).
2394
6df41af2
GS
2395=item %s found where operator expected
2396
56da5a46
RGS
2397(S syntax) The Perl lexer knows whether to expect a term or an operator.
2398If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2399operator, it gives you this warning. Usually it indicates that an
2400operator or delimiter was omitted, such as a semicolon.
6df41af2 2401
a0d0e21e
LW
2402=item gdbm store returned %d, errno %d, key "%s"
2403
2404(S) A warning from the GDBM_File extension that a store failed.
2405
2406=item gethostent not implemented
2407
2408(F) Your C library apparently doesn't implement gethostent(), probably
2409because if it did, it'd feel morally obligated to return every hostname
2410on the Internet.
2411
69282e91 2412=item get%sname() on closed socket %s
a0d0e21e 2413
be771a83
GS
2414(W closed) You tried to get a socket or peer socket name on a closed
2415socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2416
748a9306
LW
2417=item getpwnam returned invalid UIC %#o for user "%s"
2418
2419(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2420C<getpwnam> operator returned an invalid UIC.
2421
6df41af2
GS
2422=item getsockopt() on closed socket %s
2423
be771a83
GS
2424(W closed) You tried to get a socket option on a closed socket. Did you
2425forget to check the return value of your socket() call? See
6df41af2
GS
2426L<perlfunc/getsockopt>.
2427
0f539b13
BF
2428=item given is experimental
2429
675fa9ff
FC
2430(S experimental::smartmatch) C<given> depends on smartmatch, which
2431is experimental, so its behavior may change or even be removed
2432in any future release of perl. See the explanation under
2433L<perlsyn/Experimental Details on given and when>.
0f539b13 2434
68567d27
FC
2435=item Global symbol "%s" requires explicit package name (did you forget to
2436declare "my %s"?)
6df41af2 2437
a4edf47d 2438(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2439that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2440declared beforehand using "our", or explicitly qualified to say
2441which package the global variable is in (using "::").
6df41af2 2442
e476b1b5
GS
2443=item glob failed (%s)
2444
5ead438e 2445(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2446for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2447pattern that caused the external program to fail and exit with a
be771a83 2448nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2449resulted in a coredump, this may also mean that your csh (C shell)
2450is broken. If so, you should change all of the csh-related variables
2451in config.sh: If you have tcsh, make the variables refer to it as
2452if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2453all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2454think csh is missing. In either case, after editing config.sh, run
75b44862 2455C<./Configure -S> and rebuild Perl.
e476b1b5 2456
a0d0e21e
LW
2457=item Glob not terminated
2458
2459(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2460a term, so it's looking for the corresponding right angle bracket, and
2461not finding it. Chances are you left some needed parentheses out
2462earlier in the line, and you really meant a "less than".
a0d0e21e 2463
b35b96b6
JH
2464=item gmtime(%f) failed
2465
2466(W overflow) You called C<gmtime> with a number that it could not handle:
2467too large, too small, or NaN. The returned value is C<undef>.
2468
bcd05b94 2469=item gmtime(%f) too large
8b56d6ff 2470
e9200be3 2471(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2472it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2473date. This warning is also triggered with NaN (the special
fc003d4b
MS
2474not-a-number value).
2475
bcd05b94 2476=item gmtime(%f) too small
fc003d4b 2477
e9200be3 2478(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2479it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2480
6df41af2 2481=item Got an error from DosAllocMem
a0d0e21e 2482
6df41af2
GS
2483(P) An error peculiar to OS/2. Most probably you're using an obsolete
2484version of Perl, and this should not happen anyway.
a0d0e21e
LW
2485
2486=item goto must have label
2487
2488(F) Unlike with "next" or "last", you're not allowed to goto an
2489unspecified destination. See L<perlfunc/goto>.
2490
6651ba0b
FC
2491=item Goto undefined subroutine%s
2492
2493(F) You tried to call a subroutine with C<goto &sub> syntax, but
2494the indicated subroutine hasn't been defined, or if it was, it
2495has since been undefined.
2496
6fbc9859 2497=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2498S<<-- HERE> in m/%s/
1f4f6bf1
YO
2499
2500(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2501they must start with a non-digit word character. A common cause of
2502this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2503
5a25739d
FC
2504=item ()-group starts with a count
2505
2506(F) A ()-group started with a count. A count is supposed to follow
2507something: a template character or a ()-group. See L<perlfunc/pack>.
2508
fe13d51d 2509=item %s had compilation errors.
6df41af2
GS
2510
2511(F) The final summary message when a C<perl -c> fails.
2512
a0d0e21e
LW
2513=item Had to create %s unexpectedly
2514
be771a83
GS
2515(S internal) A routine asked for a symbol from a symbol table that ought
2516to have existed already, but for some reason it didn't, and had to be
2517created on an emergency basis to prevent a core dump.
a0d0e21e 2518
6df41af2
GS
2519=item %s has too many errors
2520
2521(F) The parser has given up trying to parse the program after 10 errors.
2522Further error messages would likely be uninformative.
2523
61e61fbc
JH
2524=item Hexadecimal float: exponent overflow
2525
d8f2b442 2526(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2527than the floating point supports.
2528
2529=item Hexadecimal float: exponent underflow
2530
d8f2b442 2531(W overflow) The hexadecimal floating point has a smaller exponent
b6d9b423
JH
2532than the floating point supports. With the IEEE 754 floating point,
2533this may also mean that the subnormals (formerly known as denormals)
2534are being used, which may or may not be an error.
61e61fbc 2535
5488d373 2536=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2537
2538(F) Something went horribly bad in hexadecimal float handling.
2539
61e61fbc
JH
2540=item Hexadecimal float: mantissa overflow
2541
2542(W overflow) The hexadecimal floating point literal had more bits in
2543the mantissa (the part between the 0x and the exponent, also known as
2544the fraction or the significand) than the floating point supports.
2545
40bca5ae
JH
2546=item Hexadecimal float: precision loss
2547
2548(W overflow) The hexadecimal floating point had internally more
2549digits than could be output. This can be caused by unsupported
2550long double formats, or by 64-bit integers not being available
2551(needed to retrieve the digits under some configurations).
2552
2553=item Hexadecimal float: unsupported long double format
2554
2555(F) You have configured Perl to use long doubles but
d8f2b442 2556the internals of the long double format are unknown;
40bca5ae
JH
2557therefore the hexadecimal float output is impossible.
2558
252aa082
JH
2559=item Hexadecimal number > 0xffffffff non-portable
2560
e476b1b5 2561(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2562(4294967295) and therefore non-portable between systems. See
2563L<perlport> for more on portability concerns.
252aa082 2564
8903cb82 2565=item Identifier too long
2566
2567(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2568about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2569names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2570of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2571
e0e4a6e3
FC
2572=item Ignoring zero length \N{} in character class in regex; marked by
2573S<<-- HERE> in m/%s/
fc8cd66c 2574
f3ba6905 2575(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2576zero-length sequence. When such an escape is used in a character
2577class its behavior is not well defined. Check that the correct
2578escape has been used, and the correct charname handler is in scope.
fc8cd66c 2579
6df41af2 2580=item Illegal binary digit %s
f675dbe5 2581
6df41af2 2582(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2583
6df41af2 2584=item Illegal binary digit %s ignored
a0d0e21e 2585
be771a83
GS
2586(W digit) You may have tried to use a digit other than 0 or 1 in a
2587binary number. Interpretation of the binary number stopped before the
2588offending digit.
a0d0e21e 2589
6597eb22
FC
2590=item Illegal character after '_' in prototype for %s : %s
2591
e4d150f1
FC
2592(W illegalproto) An illegal character was found in a prototype
2593declaration. The '_' in a prototype must be followed by a ';',
2594indicating the rest of the parameters are optional, or one of '@'
2595or '%', since those two will accept 0 or more final parameters.
6597eb22 2596
b913d0b8
FC
2597=item Illegal character \%o (carriage return)
2598
2599(F) Perl normally treats carriage returns in the program text as
2600it would any other whitespace, which means you should never see
2601this error when Perl was built using standard options. For some
2602reason, your version of Perl appears to have been built without
2603this support. Talk to your Perl administrator.
2604
bb6b75cd 2605=item Illegal character following sigil in a subroutine signature
d3d9da4a
DM
2606
2607(F) A parameter in a subroutine signature contained an unexpected character
d4e5761f
FC
2608following the C<$>, C<@> or C<%> sigil character. Normally the sigil
2609should be followed by the variable name or C<=> etc. Perhaps you are
d3d9da4a
DM
2610trying use a prototype while in the scope of C<use feature 'signatures'>?
2611For example:
2612
2613 sub foo ($$) {} # legal - a prototype
2614
2615 use feature 'signatures;
2616 sub foo ($$) {} # illegal - was expecting a signature
2617 sub foo ($a, $b)
2618 :prototype($$) {} # legal
2619
2620
d37a9538
ST
2621=item Illegal character in prototype for %s : %s
2622
197afce1 2623(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2624Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2625Perhaps you were trying to write a subroutine signature but didn't enable
2626that feature first (C<use feature 'signatures'>), so your signature was
2627instead interpreted as a bad prototype.
d37a9538 2628
904d85c5
RGS
2629=item Illegal declaration of anonymous subroutine
2630
2631(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2632you must always specify a block of code. See L<perlsub>.
904d85c5 2633
8e742a20
MHM
2634=item Illegal declaration of subroutine %s
2635
6903afa2 2636(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2637
a0d0e21e
LW
2638=item Illegal division by zero
2639
be771a83
GS
2640(F) You tried to divide a number by 0. Either something was wrong in
2641your logic, or you need to put a conditional in to guard against
2642meaningless input.
a0d0e21e 2643
6df41af2
GS
2644=item Illegal hexadecimal digit %s ignored
2645
be771a83
GS
2646(W digit) You may have tried to use a character other than 0 - 9 or
2647A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2648number stopped before the illegal character.
6df41af2 2649
a0d0e21e
LW
2650=item Illegal modulus zero
2651
be771a83
GS
2652(F) You tried to divide a number by 0 to get the remainder. Most
2653numbers don't take to this kindly.
a0d0e21e 2654
6df41af2 2655=item Illegal number of bits in vec
399388f4 2656
6df41af2
GS
2657(F) The number of bits in vec() (the third argument) must be a power of
2658two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2659
2660=item Illegal octal digit %s
a0d0e21e 2661
d1be9408 2662(F) You used an 8 or 9 in an octal number.
a0d0e21e 2663
399388f4 2664=item Illegal octal digit %s ignored
748a9306 2665
d1be9408 2666(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2667Interpretation of the octal number stopped before the 8 or 9.
748a9306 2668
e0e4a6e3 2669=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2670
675fa9ff 2671(F) You wrote something like
c608e803
KW
2672
2673 (?+foo)
2674
2675The C<"+"> is valid only when followed by digits, indicating a
2676capturing group. See
2677L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2678
375ed12a
JH
2679=item Illegal suidscript
2680
2681(F) The script run under suidperl was somehow illegal.
2682
fe13d51d 2683=item Illegal switch in PERL5OPT: -%c
6ff81951 2684
6df41af2 2685(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2686following switches: B<-[CDIMUdmtw]>.
6ff81951 2687
4003ea29
KW
2688=item Illegal user-defined property name
2689
2690(F) You specified a Unicode-like property name in a regular expression
2691pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2692Unicode property, and was likely meant to be a user-defined property
2693name, but it can't be one of those, as they must begin with either C<In>
2694or C<Is>. Check the spelling. See also
2695L</Can't find Unicode property definition "%s">.
2696
6df41af2 2697=item Ill-formed CRTL environ value "%s"
81e118e0 2698
75b44862 2699(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2700internal environ array, and encountered an element without the C<=>
2701delimiter used to separate keys from values. The element is ignored.
09bef843 2702
6df41af2 2703=item Ill-formed message in prime_env_iter: |%s|
54310121 2704
be771a83
GS
2705(W internal) A warning peculiar to VMS. Perl tried to read a logical
2706name or CLI symbol definition when preparing to iterate over %ENV, and
2707didn't see the expected delimiter between key and value, so the line was
2708ignored.
54310121 2709
6df41af2 2710=item (in cleanup) %s
9607fc9c 2711
be771a83
GS
2712(W misc) This prefix usually indicates that a DESTROY() method raised
2713the indicated exception. Since destructors are usually called by the
2714system at arbitrary points during execution, and often a vast number of
2715times, the warning is issued only once for any number of failures that
2716would otherwise result in the same message being repeated.
6df41af2 2717
be771a83
GS
2718Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2719also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2720
e0e4a6e3
FC
2721=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2722in m/%s/
0d0b4b3b 2723
675fa9ff 2724(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2725expression inside the construct was completely empty, or if there are
2726too many or few operands for the number of operators. Perl is not smart
2727enough to give you a more precise indication as to what is wrong.
2728
6fbc9859
MH
2729=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2730parent '%s'
2c7d6b9c
RGS
2731
2732(F) The method resolution order (MRO) of the given class is not
2733C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2734documentation in L<mro> for more information.
2735
cdd6375d
MH
2736=item Indentation on line %d of here-doc doesn't match delimiter
2737
2738(F) You have an indented here-document where one or more of its lines
2739have whitespace at the beginning that does not match the closing
2740delimiter.
2741
2742For example, line 2 below is wrong because it does not have at least
27432 spaces, but lines 1 and 3 are fine because they have at least 2:
2744
2745 if ($something) {
2746 print <<~EOF;
2747 Line 1
2748 Line 2 not
2749 Line 3
2750 EOF
2751 }
2752
2753Note that tabs and spaces are compared strictly, meaning 1 tab will
2754not match 8 spaces.
2755
6a2ed79a 2756=item Infinite recursion in regex
1a147d38
YO
2757
2758(F) You used a pattern that references itself without consuming any input
6903afa2 2759text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2760either consume text or fail.
2761
6dbe9451
NC
2762=item Initialization of state variables in list context currently forbidden
2763
dca6023d 2764(F) C<state> only permits initializing a single scalar variable, in scalar
4c9eaea6
FC
2765context. So C<state $a = 42> is allowed, but not C<state ($a) = 42>. To apply
2766state semantics to a hash or array, store a hash or array reference in a
2767scalar variable.
6dbe9451 2768
2186f873
FC
2769=item %%s[%s] in scalar context better written as $%s[%s]
2770
2771(W syntax) In scalar context, you've used an array index/value slice
2772(indicated by %) to select a single element of an array. Generally
2773it's better to ask for a scalar value (indicated by $). The difference
2774is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2775returns and when evaluating its argument, while C<%foo[&bar]> provides
2776a list context to its subscript, which can do weird things if you're
2777expecting only one subscript. When called in list context, it also
2778returns the index (what C<&bar> returns) in addition to the value.
2779
2780=item %%s{%s} in scalar context better written as $%s{%s}
2781
2782(W syntax) In scalar context, you've used a hash key/value slice
2783(indicated by %) to select a single element of a hash. Generally it's
2784better to ask for a scalar value (indicated by $). The difference
2785is that C<$foo{&bar}> always behaves like a scalar, both in the value
2786it returns and when evaluating its argument, while C<@foo{&bar}> and
2787provides a list context to its subscript, which can do weird things
2788if you're expecting only one subscript. When called in list context,
2789it also returns the key in addition to the value.
2790
a0d0e21e
LW
2791=item Insecure dependency in %s
2792
8b1a09fc 2793(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2794The tainting mechanism is turned on when you're running setuid or
2795setgid, or when you specify B<-T> to turn it on explicitly. The
2796tainting mechanism labels all data that's derived directly or indirectly
2797from the user, who is considered to be unworthy of your trust. If any
2798such data is used in a "dangerous" operation, you get this error. See
2799L<perlsec> for more information.
a0d0e21e
LW
2800
2801=item Insecure directory in %s
2802
be771a83
GS
2803(F) You can't use system(), exec(), or a piped open in a setuid or
2804setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2805the world. Also, the PATH must not contain any relative directory.
2806See L<perlsec>.
a0d0e21e 2807
62f468fc 2808=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2809
2810(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2811setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2812C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2813supplied (or potentially supplied) by the user. The script must set
2814the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2815
0e9be77f
DM
2816=item Insecure user-defined property %s
2817
2818(F) Perl detected tainted data when trying to compile a regular
2819expression that contains a call to a user-defined character property
2820function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2821See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2822
b9ef414d
FC
2823=item Integer overflow in format string for %s
2824
2825(F) The indexes and widths specified in the format string of C<printf()>
2826or C<sprintf()> are too large. The numbers must not overflow the size of
2827integers for your architecture.
2828
a7ae9550
GS
2829=item Integer overflow in %s number
2830
35928bc5 2831(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2832either as a literal or as an argument to hex() or oct() is too big for
2833your architecture, and has been converted to a floating point number.
2834On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2835representable without overflow is 0xFFFFFFFF, 037777777777, or
28360b11111111111111111111111111111111 respectively. Note that Perl
2837transparently promotes all numbers to a floating point representation
2838internally--subject to loss of precision errors in subsequent
2839operations.
bbce6d69 2840
fc89ca81
FC
2841=item Integer overflow in srand
2842
2843(S overflow) The number you have passed to srand is too big to fit
2844in your architecture's integer representation. The number has been
2845replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2846architectures). This means you may be getting less randomness than
2847you expect, because different random seeds above the maximum will
2848return the same sequence of random numbers.
2849
46314c13
JP
2850=item Integer overflow in version
2851
18da5252
FC
2852=item Integer overflow in version %d
2853
784d71ed
FC
2854(W overflow) Some portion of a version initialization is too large for
2855the size of integers for your architecture. This is not a warning
f084e84f 2856because there is no rational reason for a version to try and use an
784d71ed
FC
2857element larger than typically 2**32. This is usually caused by trying
2858to use some odd mathematical operation as a version, like 100/9.
46314c13 2859
e0e4a6e3 2860=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2861
2862(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2863The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2864discovered.
2865
748a9306
LW
2866=item Internal inconsistency in tracking vforks
2867
be771a83
GS
2868(S) A warning peculiar to VMS. Perl keeps track of the number of times
2869you've called C<fork> and C<exec>, to determine whether the current call
2870to C<exec> should affect the current script or a subprocess (see
2871L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2872Perl is making a guess and treating this C<exec> as a request to
2873terminate the Perl script and execute the specified command.
748a9306 2874
870978ae
FC
2875=item internal %<num>p might conflict with future printf extensions
2876
2877(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2878formatting follows a slightly different set of rules when called from
2879C or XS code. Specifically, formats consisting of digits followed
2880by "p" (e.g., "%7p") are reserved for future use. If you see this
2881message, then an XS module tried to call that routine with one such
2882reserved format.
2883
e0e4a6e3 2884=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2885
fa816bf3 2886(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2887S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2888discovered.
a0d0e21e 2889
6df41af2
GS
2890=item %s (...) interpreted as function
2891
75b44862 2892(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2893followed by parentheses turns into a function, with all the list
64977eb6 2894operators arguments found inside the parentheses. See
13a2d996 2895L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2896
f51551f7
FC
2897=item In '(?...)', the '(' and '?' must be adjacent in regex;
2898marked by S<<-- HERE> in m/%s/
2899
2900(F) The two-character sequence C<"(?"> in this context in a regular
2901expression pattern should be an indivisible token, with nothing
2902intervening between the C<"("> and the C<"?">, but you separated them
2903with whitespace.
2904
09bef843
SB
2905=item Invalid %s attribute: %s
2906
a4a4c9e2 2907(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2908by Perl or by a user-supplied handler. See L<attributes>.
2909
2910=item Invalid %s attributes: %s
2911
a4a4c9e2 2912(F) The indicated attributes for a subroutine or variable were not
be771a83 2913recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2914
e0e4a6e3
FC
2915=item Invalid character in charnames alias definition; marked by
2916S<<-- HERE> in '%s
225fb84f
KW
2917
2918(F) You tried to create a custom alias for a character name, with
2919the C<:alias> option to C<use charnames> and the specified character in
2920the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2921
c8028aa6
TC
2922=item Invalid \0 character in %s for %s: %s\0%s
2923
fa3234e3
FC
2924(W syscalls) Embedded \0 characters in pathnames or other system call
2925arguments produce a warning as of 5.20. The parts after the \0 were
2926formerly ignored by system calls.
c8028aa6 2927
e0e4a6e3 2928=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2929
2930(F) Only certain characters are valid for character names. The
2931indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2932
c635e13b 2933=item Invalid conversion in %s: "%s"
2934
be771a83
GS
2935(W printf) Perl does not understand the given format conversion. See
2936L<perlfunc/sprintf>.
c635e13b 2937
e0e4a6e3
FC
2938=item Invalid escape in the specified encoding in regex; marked by
2939S<<-- HERE> in m/%s/
9e08bc66 2940
98d31c73 2941(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
TS
2942didn't correspond to a single character through the conversion
2943from the encoding specified by the encoding pragma.
98d31c73
FC
2944The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2945instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2946The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
TS
2947escape was discovered.
2948
8149aa9f
FC
2949=item Invalid hexadecimal number in \N{U+...}
2950
e0e4a6e3
FC
2951=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2952S<<-- HERE> in m/%s/
aec0ef10 2953
8149aa9f 2954(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2955number. Either it is empty, or you tried to use a character other than
29560 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2957
6651ba0b
FC
2958=item Invalid module name %s with -%c option: contains single ':'
2959
2960(F) The module argument to perl's B<-m> and B<-M> command-line options
2961cannot contain single colons in the module name, but only in the
2962arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2963B<-MFoo:Bar=baz> is not.
2964
2c7d6b9c
RGS
2965=item Invalid mro name: '%s'
2966
162a3e34
FC
2967(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2968where C<foo> is not a valid method resolution order (MRO). Currently,
2969the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2970a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2971
40e4140b
FC
2972=item Invalid negative number (%s) in chr
2973
2974(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2975not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2976character (U+FFFD).
2977
74d1b2e4
FC
2978=item Invalid number '%s' for -C option.
2979
2980(F) You supplied a number to the -C option that either has extra leading
2981zeroes or overflows perl's unsigned integer representation.
2982
6651ba0b
FC
2983=item invalid option -D%c, use -D'' to see choices
2984
8ff21bfe
FC
2985(S debugging) Perl was called with invalid debugger flags. Call perl
2986with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2987See also L<perlrun/-Dletters>.
6651ba0b 2988
6e8a73f2 2989=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
2990
2991(F) The pattern looks like a {min,max} quantifier, but the min or max
2992could not be parsed as a valid number - either it has leading zeroes,
2993or it represents too big a number to cope with. The S<<-- HERE> shows
2994where in the regular expression the problem was discovered. See L<perlre>.
2995
e0e4a6e3 2996=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2997
2998(F) The range specified in a character class had a minimum character
7253e4e3
RK
2999greater than the maximum character. One possibility is that you forgot the
3000C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 3001up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 3002problem was discovered. See L<perlre>.
6df41af2 3003
d1573ac7 3004=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
3005
3006(F) The range specified in the tr/// or y/// operator had a minimum
3007character greater than the maximum character. See L<perlop>.
3008
09bef843
SB
3009=item Invalid separator character %s in attribute list
3010
0120eecf 3011(F) Something other than a colon or whitespace was seen between the
be771a83
GS
3012elements of an attribute list. If the previous attribute had a
3013parenthesised parameter list, perhaps that list was terminated too soon.
3014See L<attributes>.
09bef843 3015
b4581f09
JH
3016=item Invalid separator character %s in PerlIO layer specification %s
3017
2bfc5f71
FC
3018(W layer) When pushing layers onto the Perl I/O system, something other
3019than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
3020If the previous attribute had a parenthesised parameter list, perhaps that
3021list was terminated too soon.
3022
2c86d456
DG
3023=item Invalid strict version format (%s)
3024
fa816bf3 3025(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
3026A "strict" version number is a positive decimal number (integer or
3027decimal-fraction) without exponentiation or else a dotted-decimal
3028v-string with a leading 'v' character and at least three components.
a6485a24 3029The parenthesized text indicates which criteria were not met.
2c86d456
DG
3030See the L<version> module for more details on allowed version formats.
3031
49704364 3032=item Invalid type '%s' in %s
96e4d5b1 3033
49704364
WL
3034(F) The given character is not a valid pack or unpack type.
3035See L<perlfunc/pack>.
6728c851 3036
49704364 3037(W) The given character is not a valid pack or unpack type but used to be
75b44862 3038silently ignored.
96e4d5b1 3039
2c86d456
DG
3040=item Invalid version format (%s)
3041
fa816bf3 3042(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
3043A "lax" version number is a positive decimal number (integer or
3044decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
3045v-string. If the v-string has fewer than three components, it
3046must have a leading 'v' character. Otherwise, the leading 'v' is
3047optional. Both decimal and dotted-decimal versions may have a
3048trailing "alpha" component separated by an underscore character
3049after a fractional or dotted-decimal component. The parenthesized
3050text indicates which criteria were not met. See the L<version> module
3051for more details on allowed version formats.
46314c13 3052
798ae1b7
DG
3053=item Invalid version object
3054
fa816bf3
FC
3055(F) The internal structure of the version object was invalid.
3056Perhaps the internals were modified directly in some way or
3057an arbitrary reference was blessed into the "version" class.
798ae1b7 3058
cd209d9d 3059=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 3060marked by S<<-- HERE> in m/%s/
675fa9ff 3061
cd209d9d 3062(F) The two-character sequence C<"(*"> in
675fa9ff
FC
3063this context in a regular expression pattern should be an
3064indivisible token, with nothing intervening between the C<"(">
cd209d9d 3065and the C<"*">, but you separated them.
675fa9ff 3066
a0d0e21e
LW
3067=item ioctl is not implemented
3068
3069(F) Your machine apparently doesn't implement ioctl(), which is pretty
3070strange for a machine that supports C.
3071
c289d2f7
JH
3072=item ioctl() on unopened %s
3073
3074(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 3075Check your control flow and number of arguments.
c289d2f7 3076
fe13d51d 3077=item IO layers (like '%s') unavailable
363c40c4
SB
3078
3079(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 3080you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
3081with 'useperlio'.
3082
80cbd5ad
JH
3083=item IO::Socket::atmark not implemented on this architecture
3084
3085(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 3086neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 3087
6e8a73f2 3088=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
3089
3090(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
3091Perl. The current valid ones are given in
3092L<perlrebackslash/\b{}, \b, \B{}, \B>.
3093
74d1b2e4
FC
3094=item %s() is deprecated on :utf8 handles
3095
dd6d5da4 3096(D deprecated) The sysread(), recv(), syswrite() and send() operators are
74d1b2e4
FC
3097deprecated on handles that have the C<:utf8> layer, either explicitly, or
3098implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
3099
3100Both sysread() and recv() currently use only the C<:utf8> flag for the stream,
3101ignoring the actual layers. Since sysread() and recv() do no UTF-8
3102validation they can end up creating invalidly encoded scalars.
3103
3104Similarly, syswrite() and send() use only the C<:utf8> flag, otherwise ignoring
3105any layers. If the flag is set, both write the value UTF-8 encoded, even if
3106the layer is some different encoding, such as the example above.
3107
3108Ideally, all of these operators would completely ignore the C<:utf8> state,
3109working only with bytes, but this would result in silently breaking existing
3110code. To avoid this a future version of perl will throw an exception when
3111any of sysread(), recv(), syswrite() or send() are called on handle with the
3112C<:utf8> layer.
3113
6e8a73f2 3114=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6
KW
3115
3116(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
3117
3118You specified a character that has the given plainer way of writing it,
3119and which is also portable to platforms running with different character
3120sets.
3121
4f650b80 3122=item $* is no longer supported
b4581f09 3123
4f650b80 3124(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 3125perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
3126previous versions of perl the use of C<$*> enabled or disabled multi-line
3127matching within a string.
4fd19576
B
3128
3129Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
3130modifiers. You can enable C</m> for a lexical scope (even a whole file)
3131with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 3132then all regular expressions behaved as if they were written using C</m>.)
b4581f09 3133
8ae1fe26
RGS
3134=item $# is no longer supported
3135
a58ac25e 3136(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 3137perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 3138should use the printf/sprintf functions instead.
8ae1fe26 3139
ccf3535a 3140=item '%s' is not a code reference
6ad11d81 3141
6903afa2
FC
3142(W overload) The second (fourth, sixth, ...) argument of
3143overload::constant needs to be a code reference. Either
3144an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3145
ccf3535a 3146=item '%s' is not an overloadable type
6ad11d81 3147
04a80ee0
RGS
3148(W overload) You tried to overload a constant type the overload package is
3149unaware of.
6ad11d81 3150
5a25739d
FC
3151=item -i used with no filenames on the command line, reading from STDIN
3152
3153(S inplace) The C<-i> option was passed on the command line, indicating
3154that the script is intended to edit files in place, but no files were
3155given. This is usually a mistake, since editing STDIN in place doesn't
3156make sense, and can be confusing because it can make perl look like
3157it is hanging when it is really just trying to read from STDIN. You
3158should either pass a filename to edit, or remove C<-i> from the command
3159line. See L<perlrun> for more details.
3160
aec0ef10 3161=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3162
3163(P) The regular expression parser is confused.
3164
3165=item Label not found for "last %s"
3166
be771a83
GS
3167(F) You named a loop to break out of, but you're not currently in a loop
3168of that name, not even if you count where you were called from. See
3169L<perlfunc/last>.
a0d0e21e
LW
3170
3171=item Label not found for "next %s"
3172
3173(F) You named a loop to continue, but you're not currently in a loop of
3174that name, not even if you count where you were called from. See
3175L<perlfunc/last>.
3176
3177=item Label not found for "redo %s"
3178
3179(F) You named a loop to restart, but you're not currently in a loop of
3180that name, not even if you count where you were called from. See
3181L<perlfunc/last>.
3182
85ab1d1d 3183=item leaving effective %s failed
5ff3f7a4 3184
85ab1d1d 3185(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3186effective uids or gids failed.
3187
49704364
WL
3188=item length/code after end of string in unpack
3189
d7f8936a 3190(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3191length/code combination tried to obtain more data. This results in
3192an undefined value for the length. See L<perlfunc/pack>.
49704364 3193
25e26107 3194=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3195
0d46a4e7
FC
3196(W syntax) You used length() on either an array or a hash when you
3197probably wanted a count of the items.
e508c8a4
MH
3198
3199Array size can be obtained by doing:
3200
3201 scalar(@array);
3202
3203The number of items in a hash can be obtained by doing:
3204
3205 scalar(keys %hash);
3206
f0e67a1d
Z
3207=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3208
d4fe7078
RS
3209(F) An extension is attempting to insert text into the current parse
3210(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3211couldn't be part of the current input. This is an inherent pitfall
3212of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3213it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3214
3215=item Lexing code internal error (%s)
3216
3217(F) Lexing code supplied by an extension violated the lexer's API in a
3218detectable way.
3219
69282e91 3220=item listen() on closed socket %s
a0d0e21e 3221
be771a83
GS
3222(W closed) You tried to do a listen on a closed socket. Did you forget
3223to check the return value of your socket() call? See
3224L<perlfunc/listen>.
a0d0e21e 3225
6651ba0b
FC
3226=item List form of piped open not implemented
3227
3228(F) On some platforms, notably Windows, the three-or-more-arguments
3229form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3230Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3231
dc6bb7ba
FC
3232=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3233
3234(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3235process that was built against a different build of perl than the
3236said library was compiled against. Reinstalling the XS module will
3237likely fix this error.
3238
8c6180a9
KW
3239=item Locale '%s' may not work well.%s
3240
780fcc9f 3241(W locale) You are using the named locale, which is a non-UTF-8 one, and
dae67c56
KW
3242which perl has determined is not fully compatible with what it can
3243handle. The second C<%s> gives a reason.
8c6180a9
KW
3244
3245By far the most common reason is that the locale has characters in it
3246that are represented by more than one byte. The only such locales that
3247Perl can handle are the UTF-8 locales. Most likely the specified locale
3248is a non-UTF-8 one for an East Asian language such as Chinese or
3249Japanese. If the locale is a superset of ASCII, the ASCII portion of it
780fcc9f 3250may work in Perl.
8c6180a9
KW
3251
3252Some essentially obsolete locales that aren't supersets of ASCII, mainly
3253those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3254problems, depending on what portions of the ASCII character set get
3255changed by the locale and are also used by the program.
3256The warning message lists the determinable conflicting characters.
3257
780fcc9f
KW
3258Note that not all incompatibilities are found.
3259
3260If this happens to you, there's not much you can do except switch to use a
3261different locale or use L<Encode> to translate from the locale into
3262UTF-8; if that's impracticable, you have been warned that some things
3263may break.
3264
3265This message is output once each time a bad locale is switched into
3266within the scope of C<S<use locale>>, or on the first possibly-affected
3267operation if the C<S<use locale>> inherits a bad one. It is not raised
3268for any operations from the L<POSIX> module.
3269
a2162cd9
FC
3270=item localtime(%f) failed
3271
3272(W overflow) You called C<localtime> with a number that it could not handle:
3273too large, too small, or NaN. The returned value is C<undef>.
3274
3275=item localtime(%f) too large
3276
3277(W overflow) You called C<localtime> with a number that was larger
3278than it can reliably handle and C<localtime> probably returned the
3279wrong date. This warning is also triggered with NaN (the special
3280not-a-number value).
3281
3282=item localtime(%f) too small
3283
3284(W overflow) You called C<localtime> with a number that was smaller
3285than it can reliably handle and C<localtime> probably returned the
3286wrong date.
3287
58e23c8d 3288=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
3289
3290(F) There is currently a limit on the length of string which lookbehind can
6903afa2 3291handle. This restriction may be eased in a future release.
2e50fd82 3292
b88df990
NC
3293=item Lost precision when %s %f by 1
3294
e63e8a91
FC
3295(W imprecision) The value you attempted to increment or decrement by one
3296is too large for the underlying floating point representation to store
3297accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3298warning because it has already switched from integers to floating point
3299when values are too large for integers, and now even floating point is
3300insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 3301
93fad930 3302=item lstat() on filehandle%s
2f7da168
RK
3303
3304(W io) You tried to do an lstat on a filehandle. What did you mean
3305by that? lstat() makes sense only on filenames. (Perl did a fstat()
3306instead on the filehandle.)
3307
345d70e3 3308=item lvalue attribute %s already-defined subroutine
bb3abb05 3309
345d70e3
FC
3310(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3311attribute on or off on a Perl subroutine that is already defined
3312does not always work properly. It may or may not do what you
3313want, depending on what code is inside the subroutine, with exact
3314details subject to change between Perl versions. Only do this
3315if you really know what you are doing.
bb3abb05 3316
885ef6f5
GG
3317=item lvalue attribute ignored after the subroutine has been defined
3318
345d70e3
FC
3319(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3320subroutine an lvalue subroutine after it has been defined is
3321not permitted. To make the subroutine an lvalue subroutine,
3322add the lvalue attribute to the definition, or put the C<sub
3323foo :lvalue;> declaration before the definition.
3324
3325See also L<attributes.pm|attributes>.
885ef6f5 3326
6f1b3ab0
FC
3327=item Magical list constants are not supported
3328
3329(F) You assigned a magical array to a stash element, and then tried
3330to use the subroutine from the same slot. You are asking Perl to do
3331something it cannot do, details subject to change between Perl versions.
3332
2db62bbc 3333=item Malformed integer in [] in pack
49704364 3334
2db62bbc 3335(F) Between the brackets enclosing a numeric repeat count only digits
49704364
WL
3336are permitted. See L<perlfunc/pack>.
3337
3338=item Malformed integer in [] in unpack
3339
2db62bbc 3340(F) Between the brackets enclosing a numeric repeat count only digits
49704364
WL
3341are permitted. See L<perlfunc/pack>.
3342
6df41af2
GS
3343=item Malformed PERLLIB_PREFIX
3344
3345(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3346
3347 prefix1;prefix2
3348
3349or
6df41af2
GS
3350 prefix1 prefix2
3351
be771a83
GS
3352with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3353a builtin library search path, prefix2 is substituted. The error may
3354appear if components are not found, or are too long. See
fecfaeb8 3355"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3356
2f758a16
ST
3357=item Malformed prototype for %s: %s
3358
d37a9538
ST
3359(F) You tried to use a function with a malformed prototype. The
3360syntax of function prototypes is given a brief compile-time check for
3361obvious errors like invalid characters. A more rigorous check is run
3362when the function is called.
30d9c59b
Z
3363Perhaps the function's author was trying to write a subroutine signature
3364but didn't enable that feature first (C<use feature 'signatures'>),
3365so the signature was instead interpreted as a bad prototype.
2f758a16 3366
2b5e7bc2 3367=item Malformed UTF-8 character%s
ba210ebe 3368
7cf8d05d
KW
3369(S utf8)(F) Perl detected a string that should be UTF-8, but didn't
3370comply with UTF-8 encoding rules, or represents a code point whose
3371ordinal integer value doesn't fit into the word size of the current
3372platform (overflows). Details as to the exact malformation are given in
3373the variable, C<%s>, part of the message.
ba210ebe 3374
2575c402
JW
3375One possible cause is that you set the UTF8 flag yourself for data that
3376you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 33778-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3378
3379If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3380sequences are handled gracefully, but if you use C<:utf8>, the flag is
3381set without validating the data, possibly resulting in this error
3382message.
3383
3384See also L<Encode/"Handling Malformed Data">.
901b21bf 3385
107160e2
KW
3386=item Malformed UTF-8 character immediately after '%s'
3387
3388(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3389encoding rules. The message prints out the properly encoded characters
3390just before the first bad one. If C<utf8> warnings are enabled, a