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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
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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
c32124fe
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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
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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
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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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FC
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.
a0d0e21e
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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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FC
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
GS
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
PP
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
0c7df902
JH
669=item Cannot chr %f
670
671(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
672
5dee29d4 673=item Cannot compress %f in pack
0c7df902 674
5dee29d4
JH
675(F) You tried compressing an infinity or not-a-number as an unsigned
676integer with BER, which makes no sense.
0c7df902 677
49704364 678=item Cannot compress integer in pack
0258719b 679
717feafc
JH
680(F) An argument to pack("w",...) was too large to compress.
681The BER compressed integer format can only be used with positive
682integers, and you attempted to compress a very large number (> 1e308).
683See L<perlfunc/pack>.
0258719b 684
49704364 685=item Cannot compress negative numbers in pack
0258719b
NC
686
687(F) An argument to pack("w",...) was negative. The BER compressed integer
688format can only be used with positive integers. See L<perlfunc/pack>.
689
5c1f4d79
NC
690=item Cannot convert a reference to %s to typeglob
691
6903afa2
FC
692(F) You manipulated Perl's symbol table directly, stored a reference
693in it, then tried to access that symbol via conventional Perl syntax.
694The access triggers Perl to autovivify that typeglob, but it there is
695no legal conversion from that type of reference to a typeglob.
5c1f4d79 696
4040665a 697=item Cannot copy to %s
ba2fdce6
NC
698
699(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 700be directly assigned to.
ba2fdce6 701
b5d97229
RGS
702=item Cannot find encoding "%s"
703
704(S io) You tried to apply an encoding that did not exist to a filehandle,
705either with open() or binmode().
706
0c7df902
JH
707=item Cannot pack %f with '%c'
708
5dee29d4 709(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
710which makes no sense.
711
712=item Cannot printf %f with '%c'
713
714(F) You tried printing an infinity or not-a-number as a character (%c),
715which makes no sense. Maybe you meant '%s', or just stringifying it?
716
7355df7e
FC
717=item Cannot set tied @DB::args
718
719(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
720is not supported. (Before this error was added, it used to crash.)
721
ce65bc73
FC
722=item Cannot tie unreifiable array
723
724(P) You somehow managed to call C<tie> on an array that does not
725keep a reference count on its arguments and cannot be made to
726do so. Such arrays are not even supposed to be accessible to
727Perl code, but are only used internally.
728
46e58bd2
AC
729=item Cannot yet reorder sv_catpvfn() arguments from va_list
730
731(F) Some XS code tried to use C<sv_catpvfn()> or a related function with a
732format string that specifies explicit indexes for some of the elements, and
d4e5761f
FC
733using a C-style variable-argument list (a C<va_list>). This is not currently
734supported. XS authors wanting to do this must instead construct a C array
735of C<SV*> scalars containing the arguments.
46e58bd2 736
96ebfdd7
RK
737=item Can only compress unsigned integers in pack
738
739(F) An argument to pack("w",...) was not an integer. The BER compressed
740integer format can only be used with positive integers, and you attempted
741to compress something else. See L<perlfunc/pack>.
742
a0d0e21e
LW
743=item Can't bless non-reference value
744
745(F) Only hard references may be blessed. This is how Perl "enforces"
746encapsulation of objects. See L<perlobj>.
747
dc57907a
RGS
748=item Can't "break" in a loop topicalizer
749
0d863452 750(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 751a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
752
753=item Can't "break" outside a given block
dc57907a 754
0d863452
RH
755(F) You called C<break>, but you're not inside a C<given> block.
756
6df41af2
GS
757=item Can't call method "%s" on an undefined value
758
759(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
760object reference or package name contains an undefined value. Something
761like this will reproduce the error:
6df41af2
GS
762
763 $BADREF = undef;
764 process $BADREF 1,2,3;
765 $BADREF->process(1,2,3);
766
a0d0e21e
LW
767=item Can't call method "%s" on unblessed reference
768
54310121 769(F) A method call must know in what package it's supposed to run. It
be771a83
GS
770ordinarily finds this out from the object reference you supply, but you
771didn't supply an object reference in this case. A reference isn't an
772object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
773
774=item Can't call method "%s" without a package or object reference
775
776(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
777object reference or package name contains an expression that returns a
778defined value which is neither an object reference nor a package name.
72b5445b
GS
779Something like this will reproduce the error:
780
781 $BADREF = 42;
782 process $BADREF 1,2,3;
783 $BADREF->process(1,2,3);
784
dfe378f1
FC
785=item Can't call mro_isa_changed_in() on anonymous symbol table
786
787(P) Perl got confused as to whether a hash was a plain hash or a
788symbol table hash when trying to update @ISA caches.
789
2bf7e7b2
FC
790=item Can't call mro_method_changed_in() on anonymous symbol table
791
792(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
793not attached to the symbol table.
794
a0d0e21e
LW
795=item Can't chdir to %s
796
f703fc96 797(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
798that you can chdir to, possibly because it doesn't exist.
799
0545a864 800=item Can't check filesystem of script "%s" for nosuid
104d25b7 801
be771a83
GS
802(P) For some reason you can't check the filesystem of the script for
803nosuid.
104d25b7 804
22e74366 805=item Can't coerce %s to %s in %s
a0d0e21e
LW
806
807(F) Certain types of SVs, in particular real symbol table entries
55497cff 808(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
809say things like:
810
811 *foo += 1;
812
813You CAN say
814
815 $foo = *foo;
816 $foo += 1;
817
818but then $foo no longer contains a glob.
819
0d863452 820=item Can't "continue" outside a when block
dc57907a 821
0d863452
RH
822(F) You called C<continue>, but you're not inside a C<when>
823or C<default> block.
824
a0d0e21e
LW
825=item Can't create pipe mailbox
826
be771a83
GS
827(P) An error peculiar to VMS. The process is suffering from exhausted
828quotas or other plumbing problems.
a0d0e21e 829
eb64745e
GS
830=item Can't declare %s in "%s"
831
30c282f6
NC
832(F) Only scalar, array, and hash variables may be declared as "my", "our" or
833"state" variables. They must have ordinary identifiers as names.
a0d0e21e 834
fc7debfb
FC
835=item Can't "default" outside a topicalizer
836
837(F) You have used a C<default> block that is neither inside a
838C<foreach> loop nor a C<given> block. (Note that this error is
839issued on exit from the C<default> block, so you won't get the
840error if you use an explicit C<continue>.)
841
a2162cd9
FC
842=item Can't do inplace edit: %s is not a regular file
843
844(S inplace) You tried to use the B<-i> switch on a special file, such as
845a file in /dev, a FIFO or an uneditable directory. The file was ignored.
846
847=item Can't do inplace edit on %s: %s
848
849(S inplace) The creation of the new file failed for the indicated
850reason.
851
852=item Can't do inplace edit without backup
853
854(F) You're on a system such as MS-DOS that gets confused if you try
855reading from a deleted (but still opened) file. You have to say
856C<-i.bak>, or some such.
857
858=item Can't do inplace edit: %s would not be unique
859
860(S inplace) Your filesystem does not support filenames longer than 14
861characters and Perl was unable to create a unique filename during
862inplace editing with the B<-i> switch. The file was ignored.
863
ab0b796c
KW
864=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
865
866(W locale) You are 1) running under "C<use locale>"; 2) the current
867locale is not a UTF-8 one; 3) you tried to do the designated case-change
868operation on the specified Unicode character; and 4) the result of this
869operation would mix Unicode and locale rules, which likely conflict.
870Mixing of different rule types is forbidden, so the operation was not
871done; instead the result is the indicated value, which is the best
872available that uses entirely Unicode rules. That turns out to almost
873always be the original character, unchanged.
874
875It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
876this issue is one of the reasons why. This warning is raised when
877Unicode rules would normally cause the result of this operation to
878contain a character that is in the range specified by the locale,
8790..255, and hence is subject to the locale's rules, not Unicode's.
880
881If you are using locale purely for its characteristics related to things
882like its numeric and time formatting (and not C<LC_CTYPE>), consider
883using a restricted form of the locale pragma (see L<perllocale/The "use
884locale" pragma>) like "S<C<use locale ':not_characters'>>".
885
886Note that failed case-changing operations done as a result of
887case-insensitive C</i> regular expression matching will show up in this
888warning as having the C<fc> operation (as that is what the regular
889expression engine calls behind the scenes.)
890
a0d0e21e
LW
891=item Can't do waitpid with flags
892
be771a83
GS
893(F) This machine doesn't have either waitpid() or wait4(), so only
894waitpid() without flags is emulated.
a0d0e21e 895
a0d0e21e
LW
896=item Can't emulate -%s on #! line
897
be771a83
GS
898(F) The #! line specifies a switch that doesn't make sense at this
899point. For example, it'd be kind of silly to put a B<-x> on the #!
900line.
a0d0e21e 901
1109a392
MHM
902=item Can't %s %s-endian %ss on this platform
903
904(F) Your platform's byte-order is neither big-endian nor little-endian,
905or it has a very strange pointer size. Packing and unpacking big- or
906little-endian floating point values and pointers may not be possible.
907See L<perlfunc/pack>.
908
a0d0e21e
LW
909=item Can't exec "%s": %s
910
d1be9408 911(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
912named program for the indicated reason. Typical reasons include: the
913permissions were wrong on the file, the file wasn't found in
914C<$ENV{PATH}>, the executable in question was compiled for another
915architecture, or the #! line in a script points to an interpreter that
916can't be run for similar reasons. (Or maybe your system doesn't support
917#! at all.)
a0d0e21e
LW
918
919=item Can't exec %s
920
be771a83
GS
921(F) Perl was trying to execute the indicated program for you because
922that's what the #! line said. If that's not what you wanted, you may
923need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
924
925=item Can't execute %s
926
be771a83
GS
927(F) You used the B<-S> switch, but the copies of the script to execute
928found in the PATH did not have correct permissions.
2a92aaa0 929
6df41af2 930=item Can't find an opnumber for "%s"
2a92aaa0 931
be771a83
GS
932(F) A string of a form C<CORE::word> was given to prototype(), but there
933is no builtin with the name C<word>.
6df41af2
GS
934
935=item Can't find label %s
936
be771a83
GS
937(F) You said to goto a label that isn't mentioned anywhere that it's
938possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
939
940=item Can't find %s on PATH
941
be771a83
GS
942(F) You used the B<-S> switch, but the script to execute could not be
943found in the PATH.
a0d0e21e 944
6df41af2 945=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 946
be771a83
GS
947(F) You used the B<-S> switch, but the script to execute could not be
948found in the PATH, or at least not with the correct permissions. The
949script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
950
951=item Can't find string terminator %s anywhere before EOF
952
be771a83
GS
953(F) Perl strings can stretch over multiple lines. This message means
954that the closing delimiter was omitted. Because bracketed quotes count
955nesting levels, the following is missing its final parenthesis:
a0d0e21e 956
fb73857a
PP
957 print q(The character '(' starts a side comment.);
958
97b3d10f 959If you're getting this error from a here-document, you may have
b6b8cb97
FC
960included unseen whitespace before or after your closing tag or there
961may not be a linebreak after it. A good programmer's editor will have
962a way to help you find these characters (or lack of characters). See
963L<perlop> for the full details on here-documents.
a0d0e21e 964
660a4616
ST
965=item Can't find Unicode property definition "%s"
966
29f52644
KW
967=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
968
969(F) The named property which you specified via C<\p> or C<\P> is not one
970known to Perl. Perhaps you misspelled the name? See
e1b711da 971L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
972for a complete list of available official
973properties. If it is a
974L<user-defined property|perlunicode/User-Defined Character Properties>
975it must have been defined by the time the regular expression is
976matched.
977
978If you didn't mean to use a Unicode property, escape the C<\p>, either
979by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 980until C<\E>).
660a4616 981
b3647a36 982=item Can't fork: %s
a0d0e21e 983
be771a83
GS
984(F) A fatal error occurred while trying to fork while opening a
985pipeline.
a0d0e21e 986
b3647a36
SR
987=item Can't fork, trying again in 5 seconds
988
c973c02e 989(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
990after five seconds.
991
748a9306
LW
992=item Can't get filespec - stale stat buffer?
993
be771a83
GS
994(S) A warning peculiar to VMS. This arises because of the difference
995between access checks under VMS and under the Unix model Perl assumes.
996Under VMS, access checks are done by filename, rather than by bits in
997the stat buffer, so that ACLs and other protections can be taken into
998account. Unfortunately, Perl assumes that the stat buffer contains all
999the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 1000the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
1001the device name and FID present in the stat buffer, but this works only
1002if you haven't made a subsequent call to the CRTL stat() routine,
1003because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
1004appears, the name lookup failed, and the access-checking routine gave up
1005and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
1006routine knows about the Perl C<stat> operator and file tests, so you
1007shouldn't ever see this warning in response to a Perl command; it arises
1008only if some internal code takes stat buffers lightly.)
748a9306 1009
a0d0e21e
LW
1010=item Can't get pipe mailbox device name
1011
be771a83
GS
1012(P) An error peculiar to VMS. After creating a mailbox to act as a
1013pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
1014
1015=item Can't get SYSGEN parameter value for MAXBUF
1016
748a9306
LW
1017(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
1018mailbox buffers to be, and didn't get an answer.
a0d0e21e 1019
6df41af2 1020=item Can't "goto" into the middle of a foreach loop
a0d0e21e 1021
be771a83
GS
1022(F) A "goto" statement was executed to jump into the middle of a foreach
1023loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
1024
1025=item Can't "goto" out of a pseudo block
1026
be771a83
GS
1027(F) A "goto" statement was executed to jump out of what might look like
1028a block, except that it isn't a proper block. This usually occurs if
1029you tried to jump out of a sort() block or subroutine, which is a no-no.
1030See L<perlfunc/goto>.
a0d0e21e 1031
5a25739d
FC
1032=item Can't goto subroutine from an eval-%s
1033
1034(F) The "goto subroutine" call can't be used to jump out of an eval
1035"string" or block.
1036
9850bf21 1037=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 1038
9850bf21
RH
1039(F) The "goto subroutine" call can't be used to jump out of the
1040comparison sub for a sort(), or from a similar callback (such
1041as the reduce() function in List::Util).
1042
6df41af2
GS
1043=item Can't goto subroutine outside a subroutine
1044
be771a83
GS
1045(F) The deeply magical "goto subroutine" call can only replace one
1046subroutine call for another. It can't manufacture one out of whole
1047cloth. In general you should be calling it out of only an AUTOLOAD
1048routine anyway. See L<perlfunc/goto>.
6df41af2 1049
0b5b802d
GS
1050=item Can't ignore signal CHLD, forcing to default
1051
be771a83
GS
1052(W signal) Perl has detected that it is being run with the SIGCHLD
1053signal (sometimes known as SIGCLD) disabled. Since disabling this
1054signal will interfere with proper determination of exit status of child
1055processes, Perl has reset the signal to its default value. This
1056situation typically indicates that the parent program under which Perl
1057may be running (e.g. cron) is being very careless.
0b5b802d 1058
e2c0f81f
DG
1059=item Can't kill a non-numeric process ID
1060
1061(F) Process identifiers must be (signed) integers. It is a fatal error to
1062attempt to kill() an undefined, empty-string or otherwise non-numeric
1063process identifier.
1064
6df41af2 1065=item Can't "last" outside a loop block
4633a7c4 1066
6df41af2 1067(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1068except that there's this itty bitty problem called there isn't a current
1069block. Note that an "if" or "else" block doesn't count as a "loopish"
1070block, as doesn't a block given to sort(), map() or grep(). You can
1071usually double the curlies to get the same effect though, because the
1072inner curlies will be considered a block that loops once. See
1073L<perlfunc/last>.
4633a7c4 1074
2c7d6b9c
RGS
1075=item Can't linearize anonymous symbol table
1076
1077(F) Perl tried to calculate the method resolution order (MRO) of a
1078package, but failed because the package stash has no name.
1079
b8170e59
JB
1080=item Can't load '%s' for module %s
1081
6903afa2
FC
1082(F) The module you tried to load failed to load a dynamic extension.
1083This may either mean that you upgraded your version of perl to one
1084that is incompatible with your old dynamic extensions (which is known
1085to happen between major versions of perl), or (more likely) that your
1086dynamic extension was built against an older version of the library
1087that is installed on your system. You may need to rebuild your old
1088dynamic extensions.
b8170e59 1089
748a9306
LW
1090=item Can't localize lexical variable %s
1091
2ba9eb46 1092(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1093lexical variable using "my" or "state". This is not allowed. If you
1094want to localize a package variable of the same name, qualify it with
1095the package name.
748a9306 1096
6df41af2 1097=item Can't localize through a reference
4727527e 1098
6df41af2
GS
1099(F) You said something like C<local $$ref>, which Perl can't currently
1100handle, because when it goes to restore the old value of whatever $ref
be771a83 1101pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1102that $ref will still be a reference.
4727527e 1103
ea071790 1104=item Can't locate %s
ec889f3a 1105
fa816bf3
FC
1106(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1107Perl looks for the file in all the locations mentioned in @INC, unless
1108the file name included the full path to the file. Perhaps you need
1109to set the PERL5LIB or PERL5OPT environment variable to say where the
1110extra library is, or maybe the script needs to add the library name
be771a83
GS
1111to @INC. Or maybe you just misspelled the name of the file. See
1112L<perlfunc/require> and L<lib>.
a0d0e21e 1113
6df41af2
GS
1114=item Can't locate auto/%s.al in @INC
1115
be771a83
GS
1116(F) A function (or method) was called in a package which allows
1117autoload, but there is no function to autoload. Most probable causes
1118are a misprint in a function/method name or a failure to C<AutoSplit>
1119the file, say, by doing C<make install>.
6df41af2 1120
b8170e59
JB
1121=item Can't locate loadable object for module %s in @INC
1122
1123(F) The module you loaded is trying to load an external library, like
d70d8e57 1124for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1125unable to locate this library. See L<DynaLoader>.
1126
a0d0e21e
LW
1127=item Can't locate object method "%s" via package "%s"
1128
1129(F) You called a method correctly, and it correctly indicated a package
1130functioning as a class, but that package doesn't define that particular
2ba9eb46 1131method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1132
8af56b9d
FC
1133=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1134to load "%s"?)
1135
1136(F) You called a method on a class that did not exist, and the method
1137could not be found in UNIVERSAL. This often means that a method
1138requires a package that has not been loaded.
1139
a0d0e21e
LW
1140=item Can't locate package %s for @%s::ISA
1141
be771a83
GS
1142(W syntax) The @ISA array contained the name of another package that
1143doesn't seem to exist.
a0d0e21e 1144
2f7da168
RK
1145=item Can't locate PerlIO%s
1146
1147(F) You tried to use in open() a PerlIO layer that does not exist,
1148e.g. open(FH, ">:nosuchlayer", "somefile").
1149
f4ad53f4 1150=item Can't make list assignment to %ENV on this system
3e3baf6d 1151
be771a83
GS
1152(F) List assignment to %ENV is not supported on some systems, notably
1153VMS.
3e3baf6d 1154
cd40cd58
NC
1155=item Can't make loaded symbols global on this platform while loading %s
1156
ff9c1ae8 1157(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1158that symbols from the stated file are made available globally within the
1159process, but that functionality is not available on this platform. Whilst
1160the module likely will still work, this may prevent the perl interpreter
1161from loading other XS-based extensions which need to link directly to
1162functions defined in the C or XS code in the stated file.
1163
a0d0e21e
LW
1164=item Can't modify %s in %s
1165
be771a83
GS
1166(F) You aren't allowed to assign to the item indicated, or otherwise try
1167to change it, such as with an auto-increment.
a0d0e21e 1168
54310121 1169=item Can't modify nonexistent substring
a0d0e21e
LW
1170
1171(P) The internal routine that does assignment to a substr() was handed
1172a NULL.
1173
0f948285 1174=item Can't modify non-lvalue subroutine call of &%s
6df41af2
GS
1175
1176(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1177such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1178
cf6e1fa1
FC
1179=item Can't modify reference to %s in %s assignment
1180
1181(F) Only a limited number of constructs can be used as the argument to a
1182reference constructor on the left-hand side of an assignment, and what
1183you used was not one of them. See L<perlref/Assigning to References>.
1184
1185=item Can't modify reference to localized parenthesized array in list
1186assignment
1187
1188(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1189it is not clear exactly what it should do. If you meant to make @array
1190refer to some other array, use C<\@array = \@other_array>. If you want to
1191make the elements of @array aliases of the scalars referenced on the
1192right-hand side, use C<\(@array) = @scalar_refs>.
1193
1194=item Can't modify reference to parenthesized hash in list assignment
1195
1196(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1197refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1198make the elements of %hash into aliases of the scalars referenced on the
1199right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1200
5f05dabc 1201=item Can't msgrcv to read-only var
a0d0e21e 1202
5f05dabc 1203(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1204buffer.
1205
6df41af2
GS
1206=item Can't "next" outside a loop block
1207
1208(F) A "next" statement was executed to reiterate the current block, but
1209there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1210count as a "loopish" block, as doesn't a block given to sort(), map() or
1211grep(). You can usually double the curlies to get the same effect
1212though, because the inner curlies will be considered a block that loops
1213once. See L<perlfunc/next>.
6df41af2 1214
a0d0e21e
LW
1215=item Can't open %s: %s
1216
c47ff5f1 1217(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1218filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1219switches, or explicitly, failed for the indicated reason. Usually
1220this is because you don't have read permission for a file which
1221you named on the command line.
1222
1223(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1224your operating system's equivalent) could not be opened.
a0d0e21e 1225
9a869a14
RGS
1226=item Can't open a reference
1227
1228(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1229using the 3-arg open() syntax:
9a869a14
RGS
1230
1231 open FH, '>', $ref;
1232
1233but your version of perl is compiled without perlio, and this form of
1234open is not supported.
1235
a0d0e21e
LW
1236=item Can't open bidirectional pipe
1237
be771a83
GS
1238(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1239You can try any of several modules in the Perl library to do this, such
1240as IPC::Open2. Alternately, direct the pipe's output to a file using
1241">", and then read it in under a different file handle.
a0d0e21e 1242
748a9306
LW
1243=item Can't open error file %s as stderr
1244
be771a83
GS
1245(F) An error peculiar to VMS. Perl does its own command line
1246redirection, and couldn't open the file specified after '2>' or '2>>' on
1247the command line for writing.
748a9306
LW
1248
1249=item Can't open input file %s as stdin
1250
be771a83
GS
1251(F) An error peculiar to VMS. Perl does its own command line
1252redirection, and couldn't open the file specified after '<' on the
1253command line for reading.
748a9306
LW
1254
1255=item Can't open output file %s as stdout
1256
be771a83
GS
1257(F) An error peculiar to VMS. Perl does its own command line
1258redirection, and couldn't open the file specified after '>' or '>>' on
1259the command line for writing.
748a9306
LW
1260
1261=item Can't open output pipe (name: %s)
1262
be771a83
GS
1263(P) An error peculiar to VMS. Perl does its own command line
1264redirection, and couldn't open the pipe into which to send data destined
1265for stdout.
748a9306 1266
3b1cf97d 1267=item Can't open perl script "%s": %s
a0d0e21e
LW
1268
1269(F) The script you specified can't be opened for the indicated reason.
1270
fa3aa65a
JC
1271If you're debugging a script that uses #!, and normally relies on the
1272shell's $PATH search, the -S option causes perl to do that search, so
1273you don't have to type the path or C<`which $scriptname`>.
1274
6df41af2
GS
1275=item Can't read CRTL environ
1276
1277(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1278from the CRTL's internal environment array and discovered the array was
1279missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1280or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1281searched.
6df41af2 1282
f3106bc8
LM
1283=item Can't redeclare "%s" in "%s"
1284
1285(F) A "my", "our" or "state" declaration was found within another declaration,
1286such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1287
6df41af2
GS
1288=item Can't "redo" outside a loop block
1289
1290(F) A "redo" statement was executed to restart the current block, but
1291there isn't a current block. Note that an "if" or "else" block doesn't
1292count as a "loopish" block, as doesn't a block given to sort(), map()
1293or grep(). You can usually double the curlies to get the same effect
1294though, because the inner curlies will be considered a block that
1295loops once. See L<perlfunc/redo>.
1296
64977eb6 1297=item Can't remove %s: %s, skipping file
10f9c03d 1298
be771a83
GS
1299(S inplace) You requested an inplace edit without creating a backup
1300file. Perl was unable to remove the original file to replace it with
1301the modified file. The file was left unmodified.
10f9c03d 1302
a0d0e21e
LW
1303=item Can't rename %s to %s: %s, skipping file
1304
e476b1b5 1305(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1306probably because you don't have write permission to the directory.
a0d0e21e 1307
748a9306
LW
1308=item Can't reopen input pipe (name: %s) in binary mode
1309
be771a83
GS
1310(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1311to reopen it to accept binary data. Alas, it failed.
748a9306 1312
9415f659
KW
1313=item Can't represent character for Ox%X on this platform
1314
1315(F) There is a hard limit to how big a character code point can be due
1316to the fundamental properties of UTF-8, especially on EBCDIC
1317platforms. The given code point exceeds that. The only work-around is
1318to not use such a large code point.
1319
4f12ec0e
FC
1320=item Can't reset %ENV on this system
1321
1322(F) You called C<reset('E')> or similar, which tried to reset
1323all variables in the current package beginning with "E". In
1324the main package, that includes %ENV. Resetting %ENV is not
1325supported on some systems, notably VMS.
1326
fe13d51d 1327=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1328
1fa582fa
FC
1329(F)(P) Error resolving overloading specified by a method name (as
1330opposed to a subroutine reference): no such method callable via the
1331package. If the method name is C<???>, this is an internal error.
6df41af2 1332
cd06dffe
GS
1333=item Can't return %s from lvalue subroutine
1334
be771a83
GS
1335(F) Perl detected an attempt to return illegal lvalues (such as
1336temporary or readonly values) from a subroutine used as an lvalue. This
1337is not allowed.
cd06dffe 1338
96ebfdd7
RK
1339=item Can't return outside a subroutine
1340
1341(F) The return statement was executed in mainline code, that is, where
1342there was no subroutine call to return out of. See L<perlsub>.
1343
78f9721b
SM
1344=item Can't return %s to lvalue scalar context
1345
6903afa2
FC
1346(F) You tried to return a complete array or hash from an lvalue
1347subroutine, but you called the subroutine in a way that made Perl
1348think you meant to return only one value. You probably meant to
1349write parentheses around the call to the subroutine, which tell
1350Perl that the call should be in list context.
78f9721b 1351
a0d0e21e
LW
1352=item Can't stat script "%s"
1353
be771a83
GS
1354(P) For some reason you can't fstat() the script even though you have it
1355open already. Bizarre.
a0d0e21e 1356
a0d0e21e
LW
1357=item Can't take log of %g
1358
fb73857a 1359(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1360negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1361standard with Perl, though, if you really want to do that for the
1362negative numbers.
a0d0e21e
LW
1363
1364=item Can't take sqrt of %g
1365
1366(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1367negative number. There's a Math::Complex package that comes standard
1368with Perl, though, if you really want to do that.
a0d0e21e
LW
1369
1370=item Can't undef active subroutine
1371
1372(F) You can't undefine a routine that's currently running. You can,
1373however, redefine it while it's running, and you can even undef the
1374redefined subroutine while the old routine is running. Go figure.
1375
c81225bc 1376=item Can't upgrade %s (%d) to %d
a0d0e21e 1377
be771a83
GS
1378(P) The internal sv_upgrade routine adds "members" to an SV, making it
1379into a more specialized kind of SV. The top several SV types are so
1380specialized, however, that they cannot be interconverted. This message
1381indicates that such a conversion was attempted.
a0d0e21e 1382
6651ba0b
FC
1383=item Can't use '%c' after -mname
1384
1385(F) You tried to call perl with the B<-m> switch, but you put something
1386other than "=" after the module name.
1387
1f1ec7b5
KW
1388=item Can't use a hash as a reference
1389
1390(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1391C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1392<= 5.22.0 used to allow this syntax, but shouldn't
1393have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1394
1395=item Can't use an array as a reference
1396
1397(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1398C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1399used to allow this syntax, but shouldn't have. This
1400was deprecated in perl 5.6.1.
1f1ec7b5 1401
1db89ea5
BS
1402=item Can't use anonymous symbol table for method lookup
1403
e27ad1f2 1404(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1405table that doesn't have a name. Symbol tables can become anonymous
1406for example by undefining stashes: C<undef %Some::Package::>.
1407
96ebfdd7
RK
1408=item Can't use an undefined value as %s reference
1409
1410(F) A value used as either a hard reference or a symbolic reference must
1411be a defined value. This helps to delurk some insidious errors.
1412
6df41af2
GS
1413=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1414
be771a83
GS
1415(F) Only hard references are allowed by "strict refs". Symbolic
1416references are disallowed. See L<perlref>.
6df41af2 1417
90b75b61 1418=item Can't use %! because Errno.pm is not available
1d2dff63 1419
20561843 1420(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1421Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1422provide symbolic names for C<$!> errno values.
1423
1109a392
MHM
1424=item Can't use both '<' and '>' after type '%c' in %s
1425
1426(F) A type cannot be forced to have both big-endian and little-endian
1427byte-order at the same time, so this combination of modifiers is not
1428allowed. See L<perlfunc/pack>.
1429
e35475de
KW
1430=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1431
1432(F) defined() is not useful on arrays because it
1433checks for an undefined I<scalar> value. If you want to see if the
1434array is empty, just use C<if (@array) { # not empty }> for example.
1435
1436=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1437
1438(F) C<defined()> is not usually right on hashes.
1439
1440Although C<defined %hash> is false on a plain not-yet-used hash, it
1441becomes true in several non-obvious circumstances, including iterators,
1442weak references, stash names, even remaining true after C<undef %hash>.
1443These things make C<defined %hash> fairly useless in practice, so it now
1444generates a fatal error.
1445
1446If a check for non-empty is what you wanted then just put it in boolean
1447context (see L<perldata/Scalar values>):
1448
1449 if (%hash) {
1450 # not empty
1451 }
1452
1453If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1454variable exists then that's never really been reliable, and isn't
1455a good way to enquire about the features of a package, or whether
1456it's loaded, etc.
1457
6df41af2
GS
1458=item Can't use %s for loop variable
1459
c1f06047 1460(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1461
aab6a793 1462=item Can't use global %s in "%s"
6df41af2 1463
be771a83
GS
1464(F) You tried to declare a magical variable as a lexical variable. This
1465is not allowed, because the magic can be tied to only one location
1466(namely the global variable) and it would be incredibly confusing to
1467have variables in your program that looked like magical variables but
6df41af2
GS
1468weren't.
1469
6d3b25aa
RGS
1470=item Can't use '%c' in a group with different byte-order in %s
1471
1472(F) You attempted to force a different byte-order on a type
1473that is already inside a group with a byte-order modifier.
1474For example you cannot force little-endianness on a type that
1475is inside a big-endian group.
1476
c07a80fd
PP
1477=item Can't use "my %s" in sort comparison
1478
1479(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1480You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1481and the variable had earlier been declared as a lexical variable.
1482Either qualify the sort variable with the package name, or rename the
1483lexical variable.
1484
a0d0e21e
LW
1485=item Can't use %s ref as %s ref
1486
1487(F) You've mixed up your reference types. You have to dereference a
1488reference of the type needed. You can use the ref() function to
1489test the type of the reference, if need be.
1490
748a9306 1491=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1492
5e634d20
FC
1493=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1494
b41bf23f
FC
1495(F) You've told Perl to dereference a string, something which
1496C<use strict> blocks to prevent it happening accidentally. See
1497L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1498in a double-quoted string immediately before interpolating a variable,
1499for example in C<"user @$twitter_id">, which says to treat the contents
1500of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1501symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1502
748a9306
LW
1503=item Can't use subscript on %s
1504
1505(F) The compiler tried to interpret a bracketed expression as a
1506subscript. But to the left of the brackets was an expression that
209e7cf1 1507didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1508
6df41af2
GS
1509=item Can't use \%c to mean $%c in expression
1510
75b44862
GS
1511(W syntax) In an ordinary expression, backslash is a unary operator that
1512creates a reference to its argument. The use of backslash to indicate a
1513backreference to a matched substring is valid only as part of a regular
be771a83
GS
1514expression pattern. Trying to do this in ordinary Perl code produces a
1515value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1516instead.
6df41af2 1517
810b8aa5
GS
1518=item Can't weaken a nonreference
1519
1520(F) You attempted to weaken something that was not a reference. Only
1521references can be weakened.
1522
fc7debfb
FC
1523=item Can't "when" outside a topicalizer
1524
1525(F) You have used a when() block that is neither inside a C<foreach>
1526loop nor a C<given> block. (Note that this error is issued on exit
1527from the C<when> block, so you won't get the error if the match fails,
1528or if you use an explicit C<continue>.)
1529
5f05dabc 1530=item Can't x= to read-only value
a0d0e21e 1531
be771a83
GS
1532(F) You tried to repeat a constant value (often the undefined value)
1533with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1534Perhaps you need to copy the value to a temporary, and repeat that.
1535
a04e6aad 1536=item Character following "\c" must be printable ASCII
f9d13529 1537
7357bd17 1538(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1539
727b6379 1540Note that ASCII characters that don't map to control characters are
7357bd17 1541discouraged, and will generate the warning (when enabled)
727b6379 1542L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1543
163a633c
KW
1544=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1545
1546(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1547specified something that isn't a legal Unicode property name. Most
1548Unicode properties are specified by C<\p{...}>. But if the name is a
1549single character one, the braces may be omitted.
1550
f337b084 1551=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1552
1553(W pack) You said
1554
1555 pack("C", $x)
1556
1557where $x is either less than 0 or more than 255; the C<"C"> format is
1558only for encoding native operating system characters (ASCII, EBCDIC,
1559and so on) and not for Unicode characters, so Perl behaved as if you meant
1560
1561 pack("C", $x & 255)
1562
1563If you actually want to pack Unicode codepoints, use the C<"U"> format
1564instead.
1565
f337b084 1566=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1567
1568(W pack) You said
1569
1570 pack("c", $x)
1571
1572where $x is either less than -128 or more than 127; the C<"c"> format
1573is only for encoding native operating system characters (ASCII, EBCDIC,
1574and so on) and not for Unicode characters, so Perl behaved as if you meant
1575
1576 pack("c", $x & 255);
1577
1578If you actually want to pack Unicode codepoints, use the C<"U"> format
1579instead.
1580
f337b084
TH
1581=item Character in '%c' format wrapped in unpack
1582
1583(W unpack) You tried something like
1584
1585 unpack("H", "\x{2a1}")
1586
1a147d38 1587where the format expects to process a byte (a character with a value
6903afa2
FC
1588below 256), but a higher value was provided instead. Perl uses the
1589value modulus 256 instead, as if you had provided:
f337b084
TH
1590
1591 unpack("H", "\x{a1}")
1592
5a25739d
FC
1593=item Character in 'W' format wrapped in pack
1594
1595(W pack) You said
1596
1597 pack("U0W", $x)
1598
1599where $x is either less than 0 or more than 255. However, C<U0>-mode
1600expects all values to fall in the interval [0, 255], so Perl behaved
1601as if you meant:
1602
1603 pack("U0W", $x & 255)
1604
f337b084
TH
1605=item Character(s) in '%c' format wrapped in pack
1606
1607(W pack) You tried something like
1608
1609 pack("u", "\x{1f3}b")
1610
1a147d38 1611where the format expects to process a sequence of bytes (character with a
6903afa2 1612value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1613uses the character values modulus 256 instead, as if you had provided:
1614
1615 pack("u", "\x{f3}b")
1616
1617=item Character(s) in '%c' format wrapped in unpack
1618
1619(W unpack) You tried something like
1620
1621 unpack("s", "\x{1f3}b")
1622
1a147d38 1623where the format expects to process a sequence of bytes (character with a
6903afa2 1624value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1625uses the character values modulus 256 instead, as if you had provided:
1626
1627 unpack("s", "\x{f3}b")
1628
f51551f7
FC
1629=item charnames alias definitions may not contain a sequence of multiple spaces
1630
1631(F) You defined a character name which had multiple space characters
1632in a row. Change them to single spaces. Usually these names are
1633defined in the C<:alias> import argument to C<use charnames>, but they
1634could be defined by a translator installed into C<$^H{charnames}>. See
1635L<charnames/CUSTOM ALIASES>.
1636
1637=item charnames alias definitions may not contain trailing white-space
1638
1639(F) You defined a character name which ended in a space
1640character. Remove the trailing space(s). Usually these names are
1641defined in the C<:alias> import argument to C<use charnames>, but they
1642could be defined by a translator installed into C<$^H{charnames}>.
1643See L<charnames/CUSTOM ALIASES>.
1644
60121127
TC
1645=item chdir() on unopened filehandle %s
1646
1647(W unopened) You tried chdir() on a filehandle that was never opened.
1648
f866a7cd
FC
1649=item "\c%c" is more clearly written simply as "%s"
1650
1651(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1652non-printable characters. You used it for a printable one, which
1653is better written as simply itself, perhaps preceded by a backslash
1654for non-word characters. Doing it the way you did is not portable
1655between ASCII and EBCDIC platforms.
f866a7cd 1656
6651ba0b
FC
1657=item Cloning substitution context is unimplemented
1658
1659(F) Creating a new thread inside the C<s///> operator is not supported.
1660
abc7ecad
SP
1661=item closedir() attempted on invalid dirhandle %s
1662
1663(W io) The dirhandle you tried to close is either closed or not really
1664a dirhandle. Check your control flow.
1665
5a25739d
FC
1666=item close() on unopened filehandle %s
1667
1668(W unopened) You tried to close a filehandle that was never opened.
1669
541ed3a9
FC
1670=item Closure prototype called
1671
1672(F) If a closure has attributes, the subroutine passed to an attribute
1673handler is the prototype that is cloned when a new closure is created.
1674This subroutine cannot be called.
1675
74d1b2e4
FC
1676=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1677
1678(F) The \C character class used to allow a match of single byte
1679within a multi-byte utf-8 character, but was removed in v5.24 as
1680it broke encapsulation and its implementation was extremely buggy.
1681If you really need to process the individual bytes, you probably
1682want to convert your string to one where each underlying byte is
1683stored as a character, with utf8::encode().
1684
49704364
LW
1685=item Code missing after '/'
1686
6903afa2
FC
1687(F) You had a (sub-)template that ends with a '/'. There must be
1688another template code following the slash. See L<perlfunc/pack>.
49704364 1689
c0236afe
KW
1690=item Code point 0x%X is not Unicode, and not portable
1691
1692(S non_unicode) You had a code point that has never been in any
1693standard, so it is likely that languages other than Perl will NOT
1694understand it. At one time, it was legal in some standards to have code
1695points up to 0x7FFF_FFFF, but not higher, and this code point is higher.
1696
1697Acceptance of these code points is a Perl extension, and you should
1698expect that nothing other than Perl can handle them; Perl itself on
1699EBCDIC platforms before v5.24 does not handle them.
1700
1701Code points above 0xFFFF_FFFF require larger than a 32 bit word.
1702
1703Perl also makes no guarantees that the representation of these code
1704points won't change at some point in the future, say when machines
1705become available that have larger than a 64-bit word. At that time,
1706files written by an older Perl would require conversion before being
1707readable by a newer Perl.
1708
5a25739d
FC
1709=item Code point 0x%X is not Unicode, may not be portable
1710
2d88a86a 1711(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1712of U+10FFFF.
1713
c0236afe
KW
1714Perl allows strings to contain a superset of Unicode code points, but
1715these may not be accepted by other languages/systems. Further, even if
1716these languages/systems accept these large code points, they may have
1717chosen a different representation for them than the UTF-8-like one that
1718Perl has, which would mean files are not exchangeable between them and
1719Perl.
1720
1721On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1722representation in Perl v5.24 than before, so any file containing these
1723that was written before that version will require conversion before
1724being readable by a later Perl.
0876b9a0 1725
6df41af2
GS
1726=item %s: Command not found
1727
a892b81a 1728(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1729instead of Perl. Check the #! line, or manually feed your script into
1730Perl yourself. The #! line at the top of your file could look like
8f721816 1731
3bcfc7b3
LM
1732 #!/usr/bin/perl
1733
1734=item %s: command not found
1735
1736(A) You've accidentally run your script through B<bash> or another shell
1737instead of Perl. Check the #! line, or manually feed your script into
1738Perl yourself. The #! line at the top of your file could look like
1739
1740 #!/usr/bin/perl
1741
1742=item %s: command not found: %s
1743
1744(A) You've accidentally run your script through B<zsh> or another shell
1745instead of Perl. Check the #! line, or manually feed your script into
1746Perl yourself. The #! line at the top of your file could look like
1747
1748 #!/usr/bin/perl
6df41af2 1749
7a2e2cd6
PP
1750=item Compilation failed in require
1751
1752(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1753Perl uses this generic message when none of the errors that it
1754encountered were severe enough to halt compilation immediately.
7a2e2cd6 1755
c3464db5
DD
1756=item Complex regular subexpression recursion limit (%d) exceeded
1757
be771a83
GS
1758(W regexp) The regular expression engine uses recursion in complex
1759situations where back-tracking is required. Recursion depth is limited
1760to 32766, or perhaps less in architectures where the stack cannot grow
1761arbitrarily. ("Simple" and "medium" situations are handled without
1762recursion and are not subject to a limit.) Try shortening the string
1763under examination; looping in Perl code (e.g. with C<while>) rather than
1764in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1765that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1766on I<Mastering Regular Expressions>.)
c3464db5 1767
69282e91 1768=item connect() on closed socket %s
a0d0e21e 1769
be771a83
GS
1770(W closed) You tried to do a connect on a closed socket. Did you forget
1771to check the return value of your socket() call? See
1772L<perlfunc/connect>.
a0d0e21e 1773
e21e7c6a
FC
1774=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1775
1776(F) The subroutine registered to handle constant overloading
1777(see L<overload>) or a custom charnames handler (see
1778L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1779
1780=item Constant(%s): $^H{%s} is not defined
1781
1782(F) The parser found inconsistencies while attempting to define an
1783overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1784L<overload> pragma?
e21e7c6a 1785
779c5bc9
GS
1786=item Constant is not %s reference
1787
1788(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1789is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1790The message indicates the type of reference that was expected. This
be771a83 1791usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1792See L<perlsub/"Constant Functions"> and L<constant>.
1793
0ac016fc
FC
1794=item Constants from lexical variables potentially modified elsewhere are
1795deprecated
1796
1797(D deprecated) You wrote something like
1798
1799 my $var;
1800 $sub = sub () { $var };
1801
1802but $var is referenced elsewhere and could be modified after the C<sub>
1803expression is evaluated. Either it is explicitly modified elsewhere
1804(C<$var = 3>) or it is passed to a subroutine or to an operator like
1805C<printf> or C<map>, which may or may not modify the variable.
1806
1807Traditionally, Perl has captured the value of the variable at that
1808point and turned the subroutine into a constant eligible for inlining.
1809In those cases where the variable can be modified elsewhere, this
1810breaks the behavior of closures, in which the subroutine captures
1811the variable itself, rather than its value, so future changes to the
1812variable are reflected in the subroutine's return value.
1813
1814This usage is deprecated, because the behavior is likely to change
1815in a future version of Perl.
1816
1817If you intended for the subroutine to be eligible for inlining, then
1818make sure the variable is not referenced elsewhere, possibly by
1819copying it:
1820
1821 my $var2 = $var;
1822 $sub = sub () { $var2 };
1823
1824If you do want this subroutine to be a closure that reflects future
1825changes to the variable that it closes over, add an explicit C<return>:
1826
1827 my $var;
1828 $sub = sub () { return $var };
1829
4cee8e80
CS
1830=item Constant subroutine %s redefined
1831
aeb94125
FC
1832(W redefine)(S) You redefined a subroutine which had previously
1833been eligible for inlining. See L<perlsub/"Constant Functions">
1834for commentary and workarounds.
4cee8e80 1835
9607fc9c
PP
1836=item Constant subroutine %s undefined
1837
be771a83
GS
1838(W misc) You undefined a subroutine which had previously been eligible
1839for inlining. See L<perlsub/"Constant Functions"> for commentary and
1840workarounds.
9607fc9c 1841
5a25739d
FC
1842=item Constant(%s) unknown
1843
1844(F) The parser found inconsistencies either while attempting
1845to define an overloaded constant, or when trying to find the
1846character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1847forgot to load the corresponding L<overload> pragma?
5a25739d 1848
4a873d7a
FC
1849=item :const is experimental
1850
1851(S experimental::const_attr) The "const" attribute is experimental.
1852If you want to use the feature, disable the warning with C<no warnings
1853'experimental::const_attr'>, but know that in doing so you are taking
1854the risk that your code may break in a future Perl version.
1855
b77472f9
FC
1856=item :const is not permitted on named subroutines
1857
1858(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1859its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1860not cloned like this, so the attribute does not make sense on them.
1861
e7ea3e70
IZ
1862=item Copy method did not return a reference
1863
6903afa2 1864(F) The method which overloads "=" is buggy. See
13a2d996 1865L<overload/Copy Constructor>.
e7ea3e70 1866
4aaa4757
FC
1867=item &CORE::%s cannot be called directly
1868
1869(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1870with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1871in this package cannot yet be called that way, but must be
1872called as barewords. Something like this will work:
1873
1874 BEGIN { *shove = \&CORE::push; }
1875 shove @array, 1,2,3; # pushes on to @array
1876
6798c92b
GS
1877=item CORE::%s is not a keyword
1878
1879(F) The CORE:: namespace is reserved for Perl keywords.
1880
675fa9ff
FC
1881=item Corrupted regexp opcode %d > %d
1882
1883(P) This is either an error in Perl, or, if you're using
1884one, your L<custom regular expression engine|perlreapi>. If not the
1885latter, report the problem through the L<perlbug> utility.
1886
a0d0e21e
LW
1887=item corrupted regexp pointers
1888
1889(P) The regular expression engine got confused by what the regular
1890expression compiler gave it.
1891
1892=item corrupted regexp program
1893
be771a83
GS
1894(P) The regular expression engine got passed a regexp program without a
1895valid magic number.
a0d0e21e 1896
de42a5a9 1897=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1898
1899(P) The malloc package that comes with Perl had an internal failure.
1900
49704364
LW
1901=item Count after length/code in unpack
1902
1903(F) You had an unpack template indicating a counted-length string, but
1904you have also specified an explicit size for the string. See
1905L<perlfunc/pack>.
1906
3f645a4e
FC
1907=item Declaring references is experimental
1908
1909(S experimental::declared_refs) This warning is emitted if you use
1910a reference constructor on the right-hand side of C<my>, C<state>, C<our>, or
1911C<local>. Simply suppress the warning if you want to use the feature, but
1912know that in doing so you are taking the risk of using an experimental
1913feature which may change or be removed in a future Perl version:
1914
1915 no warnings "experimental::declared_refs";
1916 use feature "declared_refs";
1917 $fooref = my \$foo;
1918
f2cccb4c
KW
1919=for comment
1920The following are used in lib/diagnostics.t for testing two =items that
1921share the same description. Changes here need to be propagated to there
1922
6651ba0b
FC
1923=item Deep recursion on anonymous subroutine
1924
a0d0e21e
LW
1925=item Deep recursion on subroutine "%s"
1926
be771a83
GS
1927(W recursion) This subroutine has called itself (directly or indirectly)
1928100 times more than it has returned. This probably indicates an
1929infinite recursion, unless you're writing strange benchmark programs, in
1930which case it indicates something else.
a0d0e21e 1931
aad1d01f
NC
1932This threshold can be changed from 100, by recompiling the F<perl> binary,
1933setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1934
e0e4a6e3
FC
1935=item (?(DEFINE)....) does not allow branches in regex; marked by
1936S<<-- HERE> in m/%s/
bcb95744 1937
6903afa2 1938(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1939most likely cause of this error is that you left out a parenthesis inside
1940of the C<....> part.
1941
6e8a73f2 1942The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1943discovered.
1944
62658f4d
PM
1945=item %s defines neither package nor VERSION--version check failed
1946
1947(F) You said something like "use Module 42" but in the Module file
1948there are neither package declarations nor a C<$VERSION>.
1949
36447869
FC
1950=item delete argument is index/value array slice, use array slice
1951
1952(F) You used index/value array slice syntax (C<%array[...]>) as
1953the argument to C<delete>. You probably meant C<@array[...]> with
1954an @ symbol instead.
1955
1956=item delete argument is key/value hash slice, use hash slice
1957
1958(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1959C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1960
0ffcbc25
FC
1961=item delete argument is not a HASH or ARRAY element or slice
1962
4a0af295 1963(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1964such as:
1965
1966 $foo{$bar}
1967 $ref->{"susie"}[12]
1968
1969or a hash or array slice, such as:
1970
1971 @foo[$bar, $baz, $xyzzy]
1972 @{$ref->[12]}{"susie", "queue"}
1973
fc36a67e
PP
1974=item Delimiter for here document is too long
1975
be771a83
GS
1976(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1977long for Perl to handle. You have to be seriously twisted to write code
1978that triggers this error.
fc36a67e 1979
6d3b25aa
RGS
1980=item Deprecated use of my() in false conditional
1981
fa816bf3
FC
1982(D deprecated) You used a declaration similar to C<my $x if 0>. There
1983has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1984not to be cleared at scope exit when its declaration includes a false
6903afa2 1985conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1986static variable. Since we intend to fix this bug, we don't want people
6903afa2 1987relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1988declaring the variable in a separate block outside the function, eg
36fb85f3 1989
6d3b25aa
RGS
1990 sub f { my $x if 0; return $x++ }
1991
1992becomes
1993
1994 { my $x; sub f { return $x++ } }
1995
ea9d9ebc 1996Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1997lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1998
1999 sub f { state $x; return $x++ }
2000
500ab966
RGS
2001=item DESTROY created new reference to dead object '%s'
2002
2003(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
2004just being DESTROYed. Perl is confused, and prefers to abort rather
2005than to create a dangling reference.
500ab966 2006
3cdd684c
TP
2007=item Did not produce a valid header
2008
3de20fbe 2009See L</500 Server error>.
3cdd684c 2010
6df41af2
GS
2011=item %s did not return a true value
2012
2013(F) A required (or used) file must return a true value to indicate that
2014it compiled correctly and ran its initialization code correctly. It's
2015traditional to end such a file with a "1;", though any true value would
2016do. See L<perlfunc/require>.
2017
cc507455 2018=item (Did you mean &%s instead?)
4633a7c4 2019
413ff9f6
FC
2020(W misc) You probably referred to an imported subroutine &FOO as $FOO or
2021some such.
4633a7c4 2022
cc507455 2023=item (Did you mean "local" instead of "our"?)
33633739 2024
be771a83
GS
2025(W misc) Remember that "our" does not localize the declared global
2026variable. You have declared it again in the same lexical scope, which
2027seems superfluous.
33633739 2028
cc507455 2029=item (Did you mean $ or @ instead of %?)
a0d0e21e 2030
be771a83
GS
2031(W) You probably said %hash{$key} when you meant $hash{$key} or
2032@hash{@keys}. On the other hand, maybe you just meant %hash and got
2033carried away.
748a9306 2034
7e1af8bc 2035=item Died
5f05dabc
PP
2036
2037(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 2038you called it with no args and C<$@> was empty.
5f05dabc 2039
3cdd684c
TP
2040=item Document contains no data
2041
3de20fbe 2042See L</500 Server error>.
3cdd684c 2043
62658f4d
PM
2044=item %s does not define %s::VERSION--version check failed
2045
2046(F) You said something like "use Module 42" but the Module did not
943fc58e 2047define a C<$VERSION>.
62658f4d 2048
49704364
LW
2049=item '/' does not take a repeat count
2050
2051(F) You cannot put a repeat count of any kind right after the '/' code.
2052See L<perlfunc/pack>.
2053
95cb0d72
FC
2054=item Don't know how to get file name
2055
2056(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
2057somehow called on another platform. This should not happen.
2058
4021c788 2059=item Don't know how to handle magic of type \%o
a0d0e21e
LW
2060
2061(P) The internal handling of magical variables has been cursed.
2062
2063=item do_study: out of memory
2064
2065(P) This should have been caught by safemalloc() instead.
2066
6df41af2
GS
2067=item (Do you need to predeclare %s?)
2068
56da5a46
RGS
2069(S syntax) This is an educated guess made in conjunction with the message
2070"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
2071name is being referenced that hasn't been declared yet. This may be
2072because of ordering problems in your file, or because of a missing
be771a83
GS
2073"sub", "package", "require", or "use" statement. If you're referencing
2074something that isn't defined yet, you don't actually have to define the
2075subroutine or package before the current location. You can use an empty
2076"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 2077
ac206dc8
RGS
2078=item dump() better written as CORE::dump()
2079
2080(W misc) You used the obsolescent C<dump()> built-in function, without fully
2081qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
2082
84d78eb7
YO
2083=item dump is not supported
2084
2085(F) Your machine doesn't support dump/undump.
2086
a0d0e21e
LW
2087=item Duplicate free() ignored
2088
be771a83
GS
2089(S malloc) An internal routine called free() on something that had
2090already been freed.
a0d0e21e 2091
1109a392
MHM
2092=item Duplicate modifier '%c' after '%c' in %s
2093
35f0cd76
FC
2094(W unpack) You have applied the same modifier more than once after a
2095type in a pack template. See L<perlfunc/pack>.
1109a392 2096
4633a7c4
LW
2097=item elseif should be elsif
2098
fa816bf3
FC
2099(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2100it's ugly. Your code will be interpreted as an attempt to call a method
2101named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2102unlikely to be what you want.
2103
c30c479a
KW
2104=item Empty \%c in regex; marked by S<<-- HERE> in m/%s/
2105
e0e4a6e3 2106=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2107
af6f566e 2108(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 2109described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 2110a regular expression without specifying the property name.
ab13f0c7 2111
a15a3d9b
FC
2112=item ${^ENCODING} is no longer supported
2113
2114(D deprecated) The special variable C<${^ENCODING}>, formerly used to implement
2115the C<encoding> pragma, is no longer supported as of Perl 5.26.0.
2116
85ab1d1d 2117=item entering effective %s failed
5ff3f7a4 2118
85ab1d1d 2119(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2120effective uids or gids failed.
2121
c038024b
RGS
2122=item %ENV is aliased to %s
2123
2124(F) You're running under taint mode, and the C<%ENV> variable has been
2125aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2126program's environment. This is potentially insecure.
c038024b 2127
748a9306
LW
2128=item Error converting file specification %s
2129
5f05dabc 2130(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2131specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2132single form when it must operate on them directly. Either you've passed
2133an invalid file specification to Perl, or you've found a case the
2134conversion routines don't handle. Drat.
748a9306 2135
ad19ef22 2136=item Eval-group in insecure regular expression
e4d48cc9 2137
be771a83
GS
2138(F) Perl detected tainted data when trying to compile a regular
2139expression that contains the C<(?{ ... })> zero-width assertion, which
2140is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2141
ad19ef22 2142=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2143
be771a83
GS
2144(F) Perl tried to compile a regular expression containing the
2145C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2146pattern contains interpolated values. Since that is a security risk,
2147it is not allowed. If you insist, you may still do this by using the
2148C<re 'eval'> pragma or by explicitly building the pattern from an
2149interpolated string at run time and using that in an eval(). See
2150L<perlre/(?{ code })>.
e4d48cc9 2151
ad19ef22 2152=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2153
be771a83
GS
2154(F) A regular expression contained the C<(?{ ... })> zero-width
2155assertion, but that construct is only allowed when the C<use re 'eval'>
2156pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2157
e0e4a6e3
FC
2158=item EVAL without pos change exceeded limit in regex; marked by
2159S<<-- HERE> in m/%s/
1a147d38
YO
2160
2161(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2162any text. Restructure the pattern so that text is consumed.
1a147d38 2163
6e8a73f2 2164The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2165discovered.
2166
fc36a67e
PP
2167=item Excessively long <> operator
2168
2169(F) The contents of a <> operator may not exceed the maximum size of a
2170Perl identifier. If you're just trying to glob a long list of
2171filenames, try using the glob() operator, or put the filenames into a
2172variable and glob that.
2173
ed9aa3b7
SG
2174=item exec? I'm not *that* kind of operating system
2175
af8bb25a 2176(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2177OS. See L<perlport>.
ed9aa3b7 2178
fe13d51d 2179=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
2180
2181(F) The final summary message when a Perl compilation fails.
2182
0ffcbc25
FC
2183=item exists argument is not a HASH or ARRAY element or a subroutine
2184
4a0af295 2185(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2186subroutine with an ampersand, such as:
2187
2188 $foo{$bar}
2189 $ref->{"susie"}[12]
2190 &do_something
2191
2192=item exists argument is not a subroutine name
2193
ccfc2567
FC
2194(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2195and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2196
a0d0e21e
LW
2197=item Exiting eval via %s
2198
be771a83
GS
2199(W exiting) You are exiting an eval by unconventional means, such as a
2200goto, or a loop control statement.
e476b1b5
GS
2201
2202=item Exiting format via %s
2203
9a2ff54b 2204(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2205goto, or a loop control statement.
a0d0e21e 2206
0a753a76
PP
2207=item Exiting pseudo-block via %s
2208
be771a83
GS
2209(W exiting) You are exiting a rather special block construct (like a
2210sort block or subroutine) by unconventional means, such as a goto, or a
2211loop control statement. See L<perlfunc/sort>.
0a753a76 2212
a0d0e21e
LW
2213=item Exiting subroutine via %s
2214
be771a83
GS
2215(W exiting) You are exiting a subroutine by unconventional means, such
2216as a goto, or a loop control statement.
a0d0e21e
LW
2217
2218=item Exiting substitution via %s
2219
be771a83
GS
2220(W exiting) You are exiting a substitution by unconventional means, such
2221as a return, a goto, or a loop control statement.
a0d0e21e 2222
e0e4a6e3 2223=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2224
675fa9ff 2225(F) You wrote something like
c608e803
KW
2226
2227 (?13
2228
2229to denote a capturing group of the form
2230L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2231but omitted the C<")">.
2232
e0e4a6e3 2233=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2234
8b6fbf55
FC
2235(F) The C<(?[...])> extended character class regular expression construct
2236only allows character classes (including character class escapes like
2237C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2238containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2239This allows a regular expression containing just C<(?[...])> to be
2240interpolated. If you see this error message, then you probably
2241have some other C<(?...)> construct inside your character class. See
2242L<perlrecharclass/Extended Bracketed Character Classes>.
2243
baabe3fb 2244=item Experimental aliasing via reference not enabled
1f8155a2 2245
baabe3fb 2246(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2247
baabe3fb
FC
2248 no warnings "experimental::refaliasing";
2249 use feature "refaliasing";
1f8155a2
FC
2250 \$x = \$y;
2251
74d1b2e4
FC
2252=item Experimental %s on scalar is now forbidden
2253
2254(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2255C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called with a
2256scalar argument. This experiment is considered unsuccessful, and
2257has been removed. The C<postderef> feature may meet your needs better.
2258
30d9c59b
Z
2259=item Experimental subroutine signatures not enabled
2260
2261(F) To use subroutine signatures, you must first enable them:
2262
caa35032 2263 no warnings "experimental::signatures";
30d9c59b
Z
2264 use feature "signatures";
2265 sub foo ($left, $right) { ... }
2266
7b8d334a
GS
2267=item Explicit blessing to '' (assuming package main)
2268
be771a83
GS
2269(W misc) You are blessing a reference to a zero length string. This has
2270the effect of blessing the reference into the package main. This is
2271usually not what you want. Consider providing a default target package,
2272e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2273
6df41af2
GS
2274=item %s: Expression syntax
2275
be771a83
GS
2276(A) You've accidentally run your script through B<csh> instead of Perl.
2277Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2278
2279=item %s failed--call queue aborted
2280
3c10abe3
AG
2281(F) An untrapped exception was raised while executing a UNITCHECK,
2282CHECK, INIT, or END subroutine. Processing of the remainder of the
2283queue of such routines has been prematurely ended.
6df41af2 2284
502aca56
TC
2285=item Failed to close in-place edit file %s: %s
2286
2287(F) Closing an output file from in-place editing, as with the C<-i>
2288command-line switch, failed.
2289
e0e4a6e3 2290=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2291
98d31c73 2292(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2293character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2294in your false range is interpreted as a literal "-". In a C<(?[...])>
2295construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2296the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2297the problem was discovered. See L<perlre>.
73b437c8 2298
1b1ee2ef 2299=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2300
be771a83
GS
2301(P) An error peculiar to VMS. Something untoward happened in a VMS
2302system service or RTL routine; Perl's exit status should provide more
2303details. The filename in "at %s" and the line number in "line %d" tell
2304you which section of the Perl source code is distressed.
a0d0e21e
LW
2305
2306=item fcntl is not implemented
2307
2308(F) Your machine apparently doesn't implement fcntl(). What is this, a
2309PDP-11 or something?
2310
22846ab4
AB
2311=item FETCHSIZE returned a negative value
2312
2313(F) A tied array claimed to have a negative number of elements, which
2314is not possible.
2315
f337b084
TH
2316=item Field too wide in 'u' format in pack
2317
d8b5cc61 2318(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2319which can't encode values above 63. So there is no point in asking for
2320a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2321C<u63> as the format.
f337b084 2322
af8c498a 2323=item Filehandle %s opened only for input
a0d0e21e 2324
6c8d78fb
HS
2325(W io) You tried to write on a read-only filehandle. If you intended
2326it to be a read-write filehandle, you needed to open it with "+<" or
2327"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2328write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2329
af8c498a 2330=item Filehandle %s opened only for output
a0d0e21e 2331
6c8d78fb
HS
2332(W io) You tried to read from a filehandle opened only for writing, If
2333you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2334with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2335read from the file, use "<". See L<perlfunc/open>. Another possibility
2336is that you attempted to open filedescriptor 0 (also known as STDIN) for
2337output (maybe you closed STDIN earlier?).
97828cef
RGS
2338
2339=item Filehandle %s reopened as %s only for input
2340
2341(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2342as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2343previously.
2344
2345=item Filehandle STDIN reopened as %s only for output
2346
2347(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2348as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2349
2350=item Final $ should be \$ or $name
2351
2352(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2353a literal dollar sign, or was meant to introduce a variable name that
2354happens to be missing. So you have to put either the backslash or the
2355name.
a0d0e21e 2356
56e90b21
GS
2357=item flock() on closed filehandle %s
2358
be771a83 2359(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2360some time before now. Check your control flow. flock() operates on
be771a83
GS
2361filehandles. Are you attempting to call flock() on a dirhandle by the
2362same name?
56e90b21 2363
6df41af2
GS
2364=item Format not terminated
2365
2366(F) A format must be terminated by a line with a solitary dot. Perl got
2367to the end of your file without finding such a line.
2368
a0d0e21e
LW
2369=item Format %s redefined
2370
e476b1b5 2371(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2372
2373 {
271595cc 2374 no warnings 'redefine';
a0d0e21e
LW
2375 eval "format NAME =...";
2376 }
2377
a0d0e21e
LW
2378=item Found = in conditional, should be ==
2379
e476b1b5 2380(W syntax) You said
a0d0e21e
LW
2381
2382 if ($foo = 123)
2383
2384when you meant
2385
2386 if ($foo == 123)
2387
2388(or something like that).
2389
6df41af2
GS
2390=item %s found where operator expected
2391
56da5a46
RGS
2392(S syntax) The Perl lexer knows whether to expect a term or an operator.
2393If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2394operator, it gives you this warning. Usually it indicates that an
2395operator or delimiter was omitted, such as a semicolon.
6df41af2 2396
a0d0e21e
LW
2397=item gdbm store returned %d, errno %d, key "%s"
2398
2399(S) A warning from the GDBM_File extension that a store failed.
2400
2401=item gethostent not implemented
2402
2403(F) Your C library apparently doesn't implement gethostent(), probably
2404because if it did, it'd feel morally obligated to return every hostname
2405on the Internet.
2406
69282e91 2407=item get%sname() on closed socket %s
a0d0e21e 2408
be771a83
GS
2409(W closed) You tried to get a socket or peer socket name on a closed
2410socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2411
748a9306
LW
2412=item getpwnam returned invalid UIC %#o for user "%s"
2413
2414(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2415C<getpwnam> operator returned an invalid UIC.
2416
6df41af2
GS
2417=item getsockopt() on closed socket %s
2418
be771a83
GS
2419(W closed) You tried to get a socket option on a closed socket. Did you
2420forget to check the return value of your socket() call? See
6df41af2
GS
2421L<perlfunc/getsockopt>.
2422
0f539b13
BF
2423=item given is experimental
2424
675fa9ff
FC
2425(S experimental::smartmatch) C<given> depends on smartmatch, which
2426is experimental, so its behavior may change or even be removed
2427in any future release of perl. See the explanation under
2428L<perlsyn/Experimental Details on given and when>.
0f539b13 2429
68567d27
FC
2430=item Global symbol "%s" requires explicit package name (did you forget to
2431declare "my %s"?)
6df41af2 2432
a4edf47d 2433(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2434that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2435declared beforehand using "our", or explicitly qualified to say
2436which package the global variable is in (using "::").
6df41af2 2437
e476b1b5
GS
2438=item glob failed (%s)
2439
5ead438e 2440(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2441for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2442pattern that caused the external program to fail and exit with a
be771a83 2443nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2444resulted in a coredump, this may also mean that your csh (C shell)
2445is broken. If so, you should change all of the csh-related variables
2446in config.sh: If you have tcsh, make the variables refer to it as
2447if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2448all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2449think csh is missing. In either case, after editing config.sh, run
75b44862 2450C<./Configure -S> and rebuild Perl.
e476b1b5 2451
a0d0e21e
LW
2452=item Glob not terminated
2453
2454(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2455a term, so it's looking for the corresponding right angle bracket, and
2456not finding it. Chances are you left some needed parentheses out
2457earlier in the line, and you really meant a "less than".
a0d0e21e 2458
b35b96b6
JH
2459=item gmtime(%f) failed
2460
2461(W overflow) You called C<gmtime> with a number that it could not handle:
2462too large, too small, or NaN. The returned value is C<undef>.
2463
bcd05b94 2464=item gmtime(%f) too large
8b56d6ff 2465
e9200be3 2466(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2467it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2468date. This warning is also triggered with NaN (the special
fc003d4b
MS
2469not-a-number value).
2470
bcd05b94 2471=item gmtime(%f) too small
fc003d4b 2472
e9200be3 2473(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2474it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2475
6df41af2 2476=item Got an error from DosAllocMem
a0d0e21e 2477
6df41af2
GS
2478(P) An error peculiar to OS/2. Most probably you're using an obsolete
2479version of Perl, and this should not happen anyway.
a0d0e21e
LW
2480
2481=item goto must have label
2482
2483(F) Unlike with "next" or "last", you're not allowed to goto an
2484unspecified destination. See L<perlfunc/goto>.
2485
6651ba0b
FC
2486=item Goto undefined subroutine%s
2487
2488(F) You tried to call a subroutine with C<goto &sub> syntax, but
2489the indicated subroutine hasn't been defined, or if it was, it
2490has since been undefined.
2491
6fbc9859 2492=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2493S<<-- HERE> in m/%s/
1f4f6bf1
YO
2494
2495(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2496they must start with a non-digit word character. A common cause of
2497this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2498
5a25739d
FC
2499=item ()-group starts with a count
2500
2501(F) A ()-group started with a count. A count is supposed to follow
2502something: a template character or a ()-group. See L<perlfunc/pack>.
2503
fe13d51d 2504=item %s had compilation errors.
6df41af2
GS
2505
2506(F) The final summary message when a C<perl -c> fails.
2507
a0d0e21e
LW
2508=item Had to create %s unexpectedly
2509
be771a83
GS
2510(S internal) A routine asked for a symbol from a symbol table that ought
2511to have existed already, but for some reason it didn't, and had to be
2512created on an emergency basis to prevent a core dump.
a0d0e21e 2513
6df41af2
GS
2514=item %s has too many errors
2515
2516(F) The parser has given up trying to parse the program after 10 errors.
2517Further error messages would likely be uninformative.
2518
61e61fbc
JH
2519=item Hexadecimal float: exponent overflow
2520
d8f2b442 2521(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2522than the floating point supports.
2523
2524=item Hexadecimal float: exponent underflow
2525
d8f2b442 2526(W overflow) The hexadecimal floating point has a smaller exponent
b6d9b423
JH
2527than the floating point supports. With the IEEE 754 floating point,
2528this may also mean that the subnormals (formerly known as denormals)
2529are being used, which may or may not be an error.
61e61fbc 2530
5488d373 2531=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2532
2533(F) Something went horribly bad in hexadecimal float handling.
2534
61e61fbc
JH
2535=item Hexadecimal float: mantissa overflow
2536
2537(W overflow) The hexadecimal floating point literal had more bits in
2538the mantissa (the part between the 0x and the exponent, also known as
2539the fraction or the significand) than the floating point supports.
2540
40bca5ae
JH
2541=item Hexadecimal float: precision loss
2542
2543(W overflow) The hexadecimal floating point had internally more
2544digits than could be output. This can be caused by unsupported
2545long double formats, or by 64-bit integers not being available
2546(needed to retrieve the digits under some configurations).
2547
2548=item Hexadecimal float: unsupported long double format
2549
2550(F) You have configured Perl to use long doubles but
d8f2b442 2551the internals of the long double format are unknown;
40bca5ae
JH
2552therefore the hexadecimal float output is impossible.
2553
252aa082
JH
2554=item Hexadecimal number > 0xffffffff non-portable
2555
e476b1b5 2556(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2557(4294967295) and therefore non-portable between systems. See
2558L<perlport> for more on portability concerns.
252aa082 2559
8903cb82
PP
2560=item Identifier too long
2561
2562(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2563about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2564names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2565of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2566
e0e4a6e3
FC
2567=item Ignoring zero length \N{} in character class in regex; marked by
2568S<<-- HERE> in m/%s/
fc8cd66c 2569
f3ba6905 2570(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2571zero-length sequence. When such an escape is used in a character
2572class its behavior is not well defined. Check that the correct
2573escape has been used, and the correct charname handler is in scope.
fc8cd66c 2574
6df41af2 2575=item Illegal binary digit %s
f675dbe5 2576
6df41af2 2577(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2578
6df41af2 2579=item Illegal binary digit %s ignored
a0d0e21e 2580
be771a83
GS
2581(W digit) You may have tried to use a digit other than 0 or 1 in a
2582binary number. Interpretation of the binary number stopped before the
2583offending digit.
a0d0e21e 2584
6597eb22
FC
2585=item Illegal character after '_' in prototype for %s : %s
2586
e4d150f1
FC
2587(W illegalproto) An illegal character was found in a prototype
2588declaration. The '_' in a prototype must be followed by a ';',
2589indicating the rest of the parameters are optional, or one of '@'
2590or '%', since those two will accept 0 or more final parameters.
6597eb22 2591
b913d0b8
FC
2592=item Illegal character \%o (carriage return)
2593
2594(F) Perl normally treats carriage returns in the program text as
2595it would any other whitespace, which means you should never see
2596this error when Perl was built using standard options. For some
2597reason, your version of Perl appears to have been built without
2598this support. Talk to your Perl administrator.
2599
bb6b75cd 2600=item Illegal character following sigil in a subroutine signature
d3d9da4a
DM
2601
2602(F) A parameter in a subroutine signature contained an unexpected character
d4e5761f
FC
2603following the C<$>, C<@> or C<%> sigil character. Normally the sigil
2604should be followed by the variable name or C<=> etc. Perhaps you are
d3d9da4a
DM
2605trying use a prototype while in the scope of C<use feature 'signatures'>?
2606For example:
2607
2608 sub foo ($$) {} # legal - a prototype
2609
2610 use feature 'signatures;
2611 sub foo ($$) {} # illegal - was expecting a signature
2612 sub foo ($a, $b)
2613 :prototype($$) {} # legal
2614
2615
d37a9538
ST
2616=item Illegal character in prototype for %s : %s
2617
197afce1 2618(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2619Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2620Perhaps you were trying to write a subroutine signature but didn't enable
2621that feature first (C<use feature 'signatures'>), so your signature was
2622instead interpreted as a bad prototype.
d37a9538 2623
904d85c5
RGS
2624=item Illegal declaration of anonymous subroutine
2625
2626(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2627you must always specify a block of code. See L<perlsub>.
904d85c5 2628
8e742a20
MHM
2629=item Illegal declaration of subroutine %s
2630
6903afa2 2631(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2632
a0d0e21e
LW
2633=item Illegal division by zero
2634
be771a83
GS
2635(F) You tried to divide a number by 0. Either something was wrong in
2636your logic, or you need to put a conditional in to guard against
2637meaningless input.
a0d0e21e 2638
6df41af2
GS
2639=item Illegal hexadecimal digit %s ignored
2640
be771a83
GS
2641(W digit) You may have tried to use a character other than 0 - 9 or
2642A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2643number stopped before the illegal character.
6df41af2 2644
a0d0e21e
LW
2645=item Illegal modulus zero
2646
be771a83
GS
2647(F) You tried to divide a number by 0 to get the remainder. Most
2648numbers don't take to this kindly.
a0d0e21e 2649
6df41af2 2650=item Illegal number of bits in vec
399388f4 2651
6df41af2
GS
2652(F) The number of bits in vec() (the third argument) must be a power of
2653two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2654
2655=item Illegal octal digit %s
a0d0e21e 2656
d1be9408 2657(F) You used an 8 or 9 in an octal number.
a0d0e21e 2658
399388f4 2659=item Illegal octal digit %s ignored
748a9306 2660
d1be9408 2661(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2662Interpretation of the octal number stopped before the 8 or 9.
748a9306 2663
e0e4a6e3 2664=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2665
675fa9ff 2666(F) You wrote something like
c608e803
KW
2667
2668 (?+foo)
2669
2670The C<"+"> is valid only when followed by digits, indicating a
2671capturing group. See
2672L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2673
375ed12a
JH
2674=item Illegal suidscript
2675
2676(F) The script run under suidperl was somehow illegal.
2677
fe13d51d 2678=item Illegal switch in PERL5OPT: -%c
6ff81951 2679
6df41af2 2680(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2681following switches: B<-[CDIMUdmtw]>.
6ff81951 2682
4003ea29
KW
2683=item Illegal user-defined property name
2684
2685(F) You specified a Unicode-like property name in a regular expression
2686pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2687Unicode property, and was likely meant to be a user-defined property
2688name, but it can't be one of those, as they must begin with either C<In>
2689or C<Is>. Check the spelling. See also
2690L</Can't find Unicode property definition "%s">.
2691
6df41af2 2692=item Ill-formed CRTL environ value "%s"
81e118e0 2693
75b44862 2694(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2695internal environ array, and encountered an element without the C<=>
2696delimiter used to separate keys from values. The element is ignored.
09bef843 2697
6df41af2 2698=item Ill-formed message in prime_env_iter: |%s|
54310121 2699
be771a83
GS
2700(W internal) A warning peculiar to VMS. Perl tried to read a logical
2701name or CLI symbol definition when preparing to iterate over %ENV, and
2702didn't see the expected delimiter between key and value, so the line was
2703ignored.
54310121 2704
6df41af2 2705=item (in cleanup) %s
9607fc9c 2706
be771a83
GS
2707(W misc) This prefix usually indicates that a DESTROY() method raised
2708the indicated exception. Since destructors are usually called by the
2709system at arbitrary points during execution, and often a vast number of
2710times, the warning is issued only once for any number of failures that
2711would otherwise result in the same message being repeated.
6df41af2 2712
be771a83
GS
2713Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2714also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2715
e0e4a6e3
FC
2716=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2717in m/%s/
0d0b4b3b 2718
675fa9ff 2719(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2720expression inside the construct was completely empty, or if there are
2721too many or few operands for the number of operators. Perl is not smart
2722enough to give you a more precise indication as to what is wrong.
2723
6fbc9859
MH
2724=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2725parent '%s'
2c7d6b9c
RGS
2726
2727(F) The method resolution order (MRO) of the given class is not
2728C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2729documentation in L<mro> for more information.
2730
cdd6375d
MH
2731=item Indentation on line %d of here-doc doesn't match delimiter
2732
2733(F) You have an indented here-document where one or more of its lines
2734have whitespace at the beginning that does not match the closing
2735delimiter.
2736
2737For example, line 2 below is wrong because it does not have at least
27382 spaces, but lines 1 and 3 are fine because they have at least 2:
2739
2740 if ($something) {
2741 print <<~EOF;
2742 Line 1
2743 Line 2 not
2744 Line 3
2745 EOF
2746 }
2747
2748Note that tabs and spaces are compared strictly, meaning 1 tab will
2749not match 8 spaces.
2750
6a2ed79a 2751=item Infinite recursion in regex
1a147d38
YO
2752
2753(F) You used a pattern that references itself without consuming any input
6903afa2 2754text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2755either consume text or fail.
2756
6dbe9451
NC
2757=item Initialization of state variables in list context currently forbidden
2758
dca6023d 2759(F) C<state> only permits initializing a single scalar variable, in scalar
4c9eaea6
FC
2760context. So C<state $a = 42> is allowed, but not C<state ($a) = 42>. To apply
2761state semantics to a hash or array, store a hash or array reference in a
2762scalar variable.
6dbe9451 2763
2186f873
FC
2764=item %%s[%s] in scalar context better written as $%s[%s]
2765
2766(W syntax) In scalar context, you've used an array index/value slice
2767(indicated by %) to select a single element of an array. Generally
2768it's better to ask for a scalar value (indicated by $). The difference
2769is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2770returns and when evaluating its argument, while C<%foo[&bar]> provides
2771a list context to its subscript, which can do weird things if you're
2772expecting only one subscript. When called in list context, it also
2773returns the index (what C<&bar> returns) in addition to the value.
2774
2775=item %%s{%s} in scalar context better written as $%s{%s}
2776
2777(W syntax) In scalar context, you've used a hash key/value slice
2778(indicated by %) to select a single element of a hash. Generally it's
2779better to ask for a scalar value (indicated by $). The difference
2780is that C<$foo{&bar}> always behaves like a scalar, both in the value
2781it returns and when evaluating its argument, while C<@foo{&bar}> and
2782provides a list context to its subscript, which can do weird things
2783if you're expecting only one subscript. When called in list context,
2784it also returns the key in addition to the value.
2785
a0d0e21e
LW
2786=item Insecure dependency in %s
2787
8b1a09fc 2788(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2789The tainting mechanism is turned on when you're running setuid or
2790setgid, or when you specify B<-T> to turn it on explicitly. The
2791tainting mechanism labels all data that's derived directly or indirectly
2792from the user, who is considered to be unworthy of your trust. If any
2793such data is used in a "dangerous" operation, you get this error. See
2794L<perlsec> for more information.
a0d0e21e
LW
2795
2796=item Insecure directory in %s
2797
be771a83
GS
2798(F) You can't use system(), exec(), or a piped open in a setuid or
2799setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2800the world. Also, the PATH must not contain any relative directory.
2801See L<perlsec>.
a0d0e21e 2802
62f468fc 2803=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2804
2805(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2806setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2807C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2808supplied (or potentially supplied) by the user. The script must set
2809the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2810
0e9be77f
DM
2811=item Insecure user-defined property %s
2812
2813(F) Perl detected tainted data when trying to compile a regular
2814expression that contains a call to a user-defined character property
2815function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2816See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2817
b9ef414d
FC
2818=item Integer overflow in format string for %s
2819
2820(F) The indexes and widths specified in the format string of C<printf()>
2821or C<sprintf()> are too large. The numbers must not overflow the size of
2822integers for your architecture.
2823
a7ae9550
GS
2824=item Integer overflow in %s number
2825
35928bc5 2826(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2827either as a literal or as an argument to hex() or oct() is too big for
2828your architecture, and has been converted to a floating point number.
2829On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2830representable without overflow is 0xFFFFFFFF, 037777777777, or
28310b11111111111111111111111111111111 respectively. Note that Perl
2832transparently promotes all numbers to a floating point representation
2833internally--subject to loss of precision errors in subsequent
2834operations.
bbce6d69 2835
fc89ca81
FC
2836=item Integer overflow in srand
2837
2838(S overflow) The number you have passed to srand is too big to fit
2839in your architecture's integer representation. The number has been
2840replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2841architectures). This means you may be getting less randomness than
2842you expect, because different random seeds above the maximum will
2843return the same sequence of random numbers.
2844
46314c13
JP
2845=item Integer overflow in version
2846
18da5252
FC
2847=item Integer overflow in version %d
2848
784d71ed
FC
2849(W overflow) Some portion of a version initialization is too large for
2850the size of integers for your architecture. This is not a warning
f084e84f 2851because there is no rational reason for a version to try and use an
784d71ed
FC
2852element larger than typically 2**32. This is usually caused by trying
2853to use some odd mathematical operation as a version, like 100/9.
46314c13 2854
e0e4a6e3 2855=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2856
2857(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2858The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2859discovered.
2860
748a9306
LW
2861=item Internal inconsistency in tracking vforks
2862
be771a83
GS
2863(S) A warning peculiar to VMS. Perl keeps track of the number of times
2864you've called C<fork> and C<exec>, to determine whether the current call
2865to C<exec> should affect the current script or a subprocess (see
2866L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2867Perl is making a guess and treating this C<exec> as a request to
2868terminate the Perl script and execute the specified command.
748a9306 2869
870978ae
FC
2870=item internal %<num>p might conflict with future printf extensions
2871
2872(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2873formatting follows a slightly different set of rules when called from
2874C or XS code. Specifically, formats consisting of digits followed
2875by "p" (e.g., "%7p") are reserved for future use. If you see this
2876message, then an XS module tried to call that routine with one such
2877reserved format.
2878
e0e4a6e3 2879=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2880
fa816bf3 2881(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2882S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2883discovered.
a0d0e21e 2884
6df41af2
GS
2885=item %s (...) interpreted as function
2886
75b44862 2887(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2888followed by parentheses turns into a function, with all the list
64977eb6 2889operators arguments found inside the parentheses. See
13a2d996 2890L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2891
f51551f7
FC
2892=item In '(?...)', the '(' and '?' must be adjacent in regex;
2893marked by S<<-- HERE> in m/%s/
2894
2895(F) The two-character sequence C<"(?"> in this context in a regular
2896expression pattern should be an indivisible token, with nothing
2897intervening between the C<"("> and the C<"?">, but you separated them
2898with whitespace.
2899
09bef843
SB
2900=item Invalid %s attribute: %s
2901
a4a4c9e2 2902(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2903by Perl or by a user-supplied handler. See L<attributes>.
2904
2905=item Invalid %s attributes: %s
2906
a4a4c9e2 2907(F) The indicated attributes for a subroutine or variable were not
be771a83 2908recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2909
e0e4a6e3
FC
2910=item Invalid character in charnames alias definition; marked by
2911S<<-- HERE> in '%s
225fb84f
KW
2912
2913(F) You tried to create a custom alias for a character name, with
2914the C<:alias> option to C<use charnames> and the specified character in
2915the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2916
c8028aa6
TC
2917=item Invalid \0 character in %s for %s: %s\0%s
2918
fa3234e3
FC
2919(W syscalls) Embedded \0 characters in pathnames or other system call
2920arguments produce a warning as of 5.20. The parts after the \0 were
2921formerly ignored by system calls.
c8028aa6 2922
e0e4a6e3 2923=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2924
2925(F) Only certain characters are valid for character names. The
2926indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2927
c635e13b
PP
2928=item Invalid conversion in %s: "%s"
2929
be771a83
GS
2930(W printf) Perl does not understand the given format conversion. See
2931L<perlfunc/sprintf>.
c635e13b 2932
e0e4a6e3
FC
2933=item Invalid escape in the specified encoding in regex; marked by
2934S<<-- HERE> in m/%s/
9e08bc66 2935
98d31c73 2936(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2937didn't correspond to a single character through the conversion
2938from the encoding specified by the encoding pragma.
98d31c73
FC
2939The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2940instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2941The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2942escape was discovered.
2943
8149aa9f
FC
2944=item Invalid hexadecimal number in \N{U+...}
2945
e0e4a6e3
FC
2946=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2947S<<-- HERE> in m/%s/
aec0ef10 2948
8149aa9f 2949(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2950number. Either it is empty, or you tried to use a character other than
29510 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2952
6651ba0b
FC
2953=item Invalid module name %s with -%c option: contains single ':'
2954
2955(F) The module argument to perl's B<-m> and B<-M> command-line options
2956cannot contain single colons in the module name, but only in the
2957arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2958B<-MFoo:Bar=baz> is not.
2959
2c7d6b9c
RGS
2960=item Invalid mro name: '%s'
2961
162a3e34
FC
2962(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2963where C<foo> is not a valid method resolution order (MRO). Currently,
2964the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2965a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2966
40e4140b
FC
2967=item Invalid negative number (%s) in chr
2968
2969(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2970not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2971character (U+FFFD).
2972
74d1b2e4
FC
2973=item Invalid number '%s' for -C option.
2974
2975(F) You supplied a number to the -C option that either has extra leading
2976zeroes or overflows perl's unsigned integer representation.
2977
6651ba0b
FC
2978=item invalid option -D%c, use -D'' to see choices
2979
8ff21bfe
FC
2980(S debugging) Perl was called with invalid debugger flags. Call perl
2981with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2982See also L<perlrun/-Dletters>.
6651ba0b 2983
6e8a73f2 2984=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
2985
2986(F) The pattern looks like a {min,max} quantifier, but the min or max
2987could not be parsed as a valid number - either it has leading zeroes,
2988or it represents too big a number to cope with. The S<<-- HERE> shows
2989where in the regular expression the problem was discovered. See L<perlre>.
2990
e0e4a6e3 2991=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2992
2993(F) The range specified in a character class had a minimum character
7253e4e3
RK
2994greater than the maximum character. One possibility is that you forgot the
2995C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2996up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2997problem was discovered. See L<perlre>.
6df41af2 2998
d1573ac7 2999=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
3000
3001(F) The range specified in the tr/// or y/// operator had a minimum
3002character greater than the maximum character. See L<perlop>.
3003
09bef843
SB
3004=item Invalid separator character %s in attribute list
3005
0120eecf 3006(F) Something other than a colon or whitespace was seen between the
be771a83
GS
3007elements of an attribute list. If the previous attribute had a
3008parenthesised parameter list, perhaps that list was terminated too soon.
3009See L<attributes>.
09bef843 3010
b4581f09
JH
3011=item Invalid separator character %s in PerlIO layer specification %s
3012
2bfc5f71
FC
3013(W layer) When pushing layers onto the Perl I/O system, something other
3014than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
3015If the previous attribute had a parenthesised parameter list, perhaps that
3016list was terminated too soon.
3017
2c86d456
DG
3018=item Invalid strict version format (%s)
3019
fa816bf3 3020(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
3021A "strict" version number is a positive decimal number (integer or
3022decimal-fraction) without exponentiation or else a dotted-decimal
3023v-string with a leading 'v' character and at least three components.
a6485a24 3024The parenthesized text indicates which criteria were not met.
2c86d456
DG
3025See the L<version> module for more details on allowed version formats.
3026
49704364 3027=item Invalid type '%s' in %s
96e4d5b1 3028
49704364
LW
3029(F) The given character is not a valid pack or unpack type.
3030See L<perlfunc/pack>.
6728c851 3031
49704364 3032(W) The given character is not a valid pack or unpack type but used to be
75b44862 3033silently ignored.
96e4d5b1 3034
2c86d456
DG
3035=item Invalid version format (%s)
3036
fa816bf3 3037(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
3038A "lax" version number is a positive decimal number (integer or
3039decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
3040v-string. If the v-string has fewer than three components, it
3041must have a leading 'v' character. Otherwise, the leading 'v' is
3042optional. Both decimal and dotted-decimal versions may have a
3043trailing "alpha" component separated by an underscore character
3044after a fractional or dotted-decimal component. The parenthesized
3045text indicates which criteria were not met. See the L<version> module
3046for more details on allowed version formats.
46314c13 3047
798ae1b7
DG
3048=item Invalid version object
3049
fa816bf3
FC
3050(F) The internal structure of the version object was invalid.
3051Perhaps the internals were modified directly in some way or
3052an arbitrary reference was blessed into the "version" class.
798ae1b7 3053
cd209d9d 3054=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 3055marked by S<<-- HERE> in m/%s/
675fa9ff 3056
cd209d9d 3057(F) The two-character sequence C<"(*"> in
675fa9ff
FC
3058this context in a regular expression pattern should be an
3059indivisible token, with nothing intervening between the C<"(">
cd209d9d 3060and the C<"*">, but you separated them.
675fa9ff 3061
a0d0e21e
LW
3062=item ioctl is not implemented
3063
3064(F) Your machine apparently doesn't implement ioctl(), which is pretty
3065strange for a machine that supports C.
3066
c289d2f7
JH
3067=item ioctl() on unopened %s
3068
3069(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 3070Check your control flow and number of arguments.
c289d2f7 3071
fe13d51d 3072=item IO layers (like '%s') unavailable
363c40c4
SB
3073
3074(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 3075you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
3076with 'useperlio'.
3077
80cbd5ad
JH
3078=item IO::Socket::atmark not implemented on this architecture
3079
3080(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 3081neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 3082
6e8a73f2 3083=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
3084
3085(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
3086Perl. The current valid ones are given in
3087L<perlrebackslash/\b{}, \b, \B{}, \B>.
3088
74d1b2e4
FC
3089=item %s() is deprecated on :utf8 handles
3090
dd6d5da4 3091(D deprecated) The sysread(), recv(), syswrite() and send() operators are
74d1b2e4
FC
3092deprecated on handles that have the C<:utf8> layer, either explicitly, or
3093implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
3094
3095Both sysread() and recv() currently use only the C<:utf8> flag for the stream,
3096ignoring the actual layers. Since sysread() and recv() do no UTF-8
3097validation they can end up creating invalidly encoded scalars.
3098
3099Similarly, syswrite() and send() use only the C<:utf8> flag, otherwise ignoring
3100any layers. If the flag is set, both write the value UTF-8 encoded, even if
3101the layer is some different encoding, such as the example above.
3102
3103Ideally, all of these operators would completely ignore the C<:utf8> state,
3104working only with bytes, but this would result in silently breaking existing
3105code. To avoid this a future version of perl will throw an exception when
3106any of sysread(), recv(), syswrite() or send() are called on handle with the
3107C<:utf8> layer.
3108
6e8a73f2 3109=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6
KW
3110
3111(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
3112
3113You specified a character that has the given plainer way of writing it,
3114and which is also portable to platforms running with different character
3115sets.
3116
4f650b80 3117=item $* is no longer supported
b4581f09 3118
4f650b80 3119(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 3120perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
3121previous versions of perl the use of C<$*> enabled or disabled multi-line
3122matching within a string.
4fd19576
B
3123
3124Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
3125modifiers. You can enable C</m> for a lexical scope (even a whole file)
3126with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 3127then all regular expressions behaved as if they were written using C</m>.)
b4581f09 3128
8ae1fe26
RGS
3129=item $# is no longer supported
3130
a58ac25e 3131(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 3132perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 3133should use the printf/sprintf functions instead.
8ae1fe26 3134
ccf3535a 3135=item '%s' is not a code reference
6ad11d81 3136
6903afa2
FC
3137(W overload) The second (fourth, sixth, ...) argument of
3138overload::constant needs to be a code reference. Either
3139an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3140
ccf3535a 3141=item '%s' is not an overloadable type
6ad11d81 3142
04a80ee0
RGS
3143(W overload) You tried to overload a constant type the overload package is
3144unaware of.
6ad11d81 3145
5a25739d
FC
3146=item -i used with no filenames on the command line, reading from STDIN
3147
3148(S inplace) The C<-i> option was passed on the command line, indicating
3149that the script is intended to edit files in place, but no files were
3150given. This is usually a mistake, since editing STDIN in place doesn't
3151make sense, and can be confusing because it can make perl look like
3152it is hanging when it is really just trying to read from STDIN. You
3153should either pass a filename to edit, or remove C<-i> from the command
3154line. See L<perlrun> for more details.
3155
aec0ef10 3156=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3157
3158(P) The regular expression parser is confused.
3159
3160=item Label not found for "last %s"
3161
be771a83
GS
3162(F) You named a loop to break out of, but you're not currently in a loop
3163of that name, not even if you count where you were called from. See
3164L<perlfunc/last>.
a0d0e21e
LW
3165
3166=item Label not found for "next %s"
3167
3168(F) You named a loop to continue, but you're not currently in a loop of
3169that name, not even if you count where you were called from. See
3170L<perlfunc/last>.
3171
3172=item Label not found for "redo %s"
3173
3174(F) You named a loop to restart, but you're not currently in a loop of
3175that name, not even if you count where you were called from. See
3176L<perlfunc/last>.
3177
85ab1d1d 3178=item leaving effective %s failed
5ff3f7a4 3179
85ab1d1d 3180(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3181effective uids or gids failed.
3182
49704364
LW
3183=item length/code after end of string in unpack
3184
d7f8936a 3185(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3186length/code combination tried to obtain more data. This results in
3187an undefined value for the length. See L<perlfunc/pack>.
49704364 3188
25e26107 3189=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3190
0d46a4e7
FC
3191(W syntax) You used length() on either an array or a hash when you
3192probably wanted a count of the items.
e508c8a4
MH
3193
3194Array size can be obtained by doing:
3195
3196 scalar(@array);
3197
3198The number of items in a hash can be obtained by doing:
3199
3200 scalar(keys %hash);
3201
f0e67a1d
Z
3202=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3203
d4fe7078
RS
3204(F) An extension is attempting to insert text into the current parse
3205(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3206couldn't be part of the current input. This is an inherent pitfall
3207of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3208it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3209
3210=item Lexing code internal error (%s)
3211
3212(F) Lexing code supplied by an extension violated the lexer's API in a
3213detectable way.
3214
69282e91 3215=item listen() on closed socket %s
a0d0e21e 3216
be771a83
GS
3217(W closed) You tried to do a listen on a closed socket. Did you forget
3218to check the return value of your socket() call? See
3219L<perlfunc/listen>.
a0d0e21e 3220
6651ba0b
FC
3221=item List form of piped open not implemented
3222
3223(F) On some platforms, notably Windows, the three-or-more-arguments
3224form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3225Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3226
dc6bb7ba
FC
3227=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3228
3229(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3230process that was built against a different build of perl than the
3231said library was compiled against. Reinstalling the XS module will
3232likely fix this error.
3233
8c6180a9
KW
3234=item Locale '%s' may not work well.%s
3235
780fcc9f 3236(W locale) You are using the named locale, which is a non-UTF-8 one, and
dae67c56
KW
3237which perl has determined is not fully compatible with what it can
3238handle. The second C<%s> gives a reason.
8c6180a9
KW
3239
3240By far the most common reason is that the locale has characters in it
3241that are represented by more than one byte. The only such locales that
3242Perl can handle are the UTF-8 locales. Most likely the specified locale
3243is a non-UTF-8 one for an East Asian language such as Chinese or
3244Japanese. If the locale is a superset of ASCII, the ASCII portion of it
780fcc9f 3245may work in Perl.
8c6180a9
KW
3246
3247Some essentially obsolete locales that aren't supersets of ASCII, mainly
3248those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3249problems, depending on what portions of the ASCII character set get
3250changed by the locale and are also used by the program.
3251The warning message lists the determinable conflicting characters.
3252
780fcc9f
KW
3253Note that not all incompatibilities are found.
3254
3255If this happens to you, there's not much you can do except switch to use a
3256different locale or use L<Encode> to translate from the locale into
3257UTF-8; if that's impracticable, you have been warned that some things
3258may break.
3259
3260This message is output once each time a bad locale is switched into
3261within the scope of C<S<use locale>>, or on the first possibly-affected
3262operation if the C<S<use locale>> inherits a bad one. It is not raised
3263for any operations from the L<POSIX> module.
3264
a2162cd9
FC
3265=item localtime(%f) failed
3266
3267(W overflow) You called C<localtime> with a number that it could not handle:
3268too large, too small, or NaN. The returned value is C<undef>.
3269
3270=item localtime(%f) too large
3271
3272(W overflow) You called C<localtime> with a number that was larger
3273than it can reliably handle and C<localtime> probably returned the
3274wrong date. This warning is also triggered with NaN (the special
3275not-a-number value).
3276
3277=item localtime(%f) too small
3278
3279(W overflow) You called C<localtime> with a number that was smaller
3280than it can reliably handle and C<localtime> probably returned the
3281wrong date.
3282
58e23c8d 3283=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
3284
3285(F) There is currently a limit on the length of string which lookbehind can
6903afa2 3286handle. This restriction may be eased in a future release.
2e50fd82 3287
b88df990
NC
3288=item Lost precision when %s %f by 1
3289
e63e8a91
FC
3290(W imprecision) The value you attempted to increment or decrement by one
3291is too large for the underlying floating point representation to store
3292accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3293warning because it has already switched from integers to floating point
3294when values are too large for integers, and now even floating point is
3295insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 3296
93fad930 3297=item lstat() on filehandle%s
2f7da168
RK
3298
3299(W io) You tried to do an lstat on a filehandle. What did you mean
3300by that? lstat() makes sense only on filenames. (Perl did a fstat()
3301instead on the filehandle.)
3302
345d70e3 3303=item lvalue attribute %s already-defined subroutine
bb3abb05 3304
345d70e3
FC
3305(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3306attribute on or off on a Perl subroutine that is already defined
3307does not always work properly. It may or may not do what you
3308want, depending on what code is inside the subroutine, with exact
3309details subject to change between Perl versions. Only do this
3310if you really know what you are doing.
bb3abb05 3311
885ef6f5
GG
3312=item lvalue attribute ignored after the subroutine has been defined
3313
345d70e3
FC
3314(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3315subroutine an lvalue subroutine after it has been defined is
3316not permitted. To make the subroutine an lvalue subroutine,
3317add the lvalue attribute to the definition, or put the C<sub
3318foo :lvalue;> declaration before the definition.
3319
3320See also L<attributes.pm|attributes>.
885ef6f5 3321
6f1b3ab0
FC
3322=item Magical list constants are not supported
3323
3324(F) You assigned a magical array to a stash element, and then tried
3325to use the subroutine from the same slot. You are asking Perl to do
3326something it cannot do, details subject to change between Perl versions.
3327
2db62bbc 3328=item Malformed integer in [] in pack
49704364 3329
2db62bbc 3330(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3331are permitted. See L<perlfunc/pack>.
3332
3333=item Malformed integer in [] in unpack
3334
2db62bbc 3335(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3336are permitted. See L<perlfunc/pack>.
3337
6df41af2
GS
3338=item Malformed PERLLIB_PREFIX
3339
3340(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3341
3342 prefix1;prefix2
3343
3344or
6df41af2
GS
3345 prefix1 prefix2
3346
be771a83
GS
3347with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3348a builtin library search path, prefix2 is substituted. The error may
3349appear if components are not found, or are too long. See
fecfaeb8 3350"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3351
2f758a16
ST
3352=item Malformed prototype for %s: %s
3353
d37a9538
ST
3354(F) You tried to use a function with a malformed prototype. The
3355syntax of function prototypes is given a brief compile-time check for
3356obvious errors like invalid characters. A more rigorous check is run
3357when the function is called.
30d9c59b
Z
3358Perhaps the function's author was trying to write a subroutine signature
3359but didn't enable that feature first (C<use feature 'signatures'>),
3360so the signature was instead interpreted as a bad prototype.
2f758a16 3361
2b5e7bc2 3362=item Malformed UTF-8 character%s
ba210ebe 3363
7cf8d05d
KW
3364(S utf8)(F) Perl detected a string that should be UTF-8, but didn't
3365comply with UTF-8 encoding rules, or represents a code point whose
3366ordinal integer value doesn't fit into the word size of the current
3367platform (overflows). Details as to the exact malformation are given in
3368the variable, C<%s>, part of the message.
ba210ebe 3369
2575c402
JW
3370One possible cause is that you set the UTF8 flag yourself for data that
3371you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 33728-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3373
3374If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3375sequences are handled gracefully, but if you use C<:utf8>, the flag is
3376set without validating the data, possibly resulting in this error
3377message.
3378
3379See also L<Encode/"Handling Malformed Data">.
901b21bf 3380
107160e2
KW
3381=item Malformed UTF-8 character immediately after '%s'
3382
3383(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3384encoding rules. The message prints out the properly encoded characters
3385just before the first bad one. If C<utf8> warnings are enabled, a
3386warning is generated that gives more details about the type of
3387malformation.
3388
bde9e88d