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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
de42a5a9 53=item Allocation too large: %x
a0d0e21e 54
6df41af2 55(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 56
04f74579 57=item '%c' allowed only after types %s in %s
ef54e1a4 58
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59(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60after certain types. See L<perlfunc/pack>.
ef54e1a4 61
6df41af2 62=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 63
75b44862 64(W ambiguous) A subroutine you have declared has the same name as a Perl
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65keyword, and you have used the name without qualification for calling
66one or the other. Perl decided to call the builtin because the
67subroutine is not imported.
43192e07 68
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69To force interpretation as a subroutine call, either put an ampersand
70before the subroutine name, or qualify the name with its package.
71Alternatively, you can import the subroutine (or pretend that it's
72imported with the C<use subs> pragma).
43192e07 73
6df41af2 74To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 75on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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76to be an object method (see L<perlsub/"Subroutine Attributes"> or
77L<attributes>).
43192e07 78
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79=item Ambiguous range in transliteration operator
80
81(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82all. To include a C<-> character in a transliteration, put it either
83first or last. (In the past, C<tr/a-z-0//> was synonymous with
84C<tr/a-y//>, which was probably not what you would have expected.)
85
6df41af2 86=item Ambiguous use of %s resolved as %s
43192e07 87
7c7af292 88(S ambiguous) You said something that may not be interpreted the way
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89you thought. Normally it's pretty easy to disambiguate it by supplying
90a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 91
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92=item Ambiguous use of -%s resolved as -&%s()
93
94(S ambiguous) You wrote something like C<-foo>, which might be the
95string C<"-foo">, or a call to the function C<foo>, negated. If you meant
96the string, just write C<"-foo">. If you meant the function call,
97write C<-foo()>.
98
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99=item Ambiguous use of %c resolved as operator %c
100
7c7af292 101(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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102bitwise and, and multiplication) I<and> initial special characters
103(denoting hashes, subroutines and typeglobs), and you said something
104like C<*foo * foo> that might be interpreted as either of them. We
105assumed you meant the infix operator, but please try to make it more
106clear -- in the example given, you might write C<*foo * foo()> if you
107really meant to multiply a glob by the result of calling a function.
d8225693 108
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109=item Ambiguous use of %c{%s} resolved to %c%s
110
111(W ambiguous) You wrote something like C<@{foo}>, which might be
112asking for the variable C<@foo>, or it might be calling a function
113named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 114the variable, you can just write C<@foo>. If you wanted to call the
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115function, write C<@{foo()}> ... or you could just not have a variable
116and a function with the same name, and save yourself a lot of trouble.
117
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118=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
119
120=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 121
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122(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
123the name of a Perl keyword), which might be looking for element number
1242 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
125might have meant to pass an anonymous arrayref to the function named
126foo, and then do a scalar deref on the value it returns. If you meant
127that, write C<${foo([2])}>.
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128
129In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130to disambiguate between array subscripts and character classes.
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131C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
132by the character class C<[2345]>. If an array subscript is what you
133want, you can avoid the warning by changing C</${length[2345]}/> to the
134unsightly C</${\$length[2345]}/>, by renaming your array to something
135that does not coincide with a built-in keyword, or by simply turning
136off warnings with C<no warnings 'ambiguous';>.
4da60377 137
6df41af2 138=item '|' and '<' may not both be specified on command line
a0d0e21e 139
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140(F) An error peculiar to VMS. Perl does its own command line
141redirection, and found that STDIN was a pipe, and that you also tried to
142redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 143
6df41af2 144=item '|' and '>' may not both be specified on command line
1028017a 145
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146(F) An error peculiar to VMS. Perl does its own command line
147redirection, and thinks you tried to redirect stdout both to a file and
148into a pipe to another command. You need to choose one or the other,
149though nothing's stopping you from piping into a program or Perl script
150which 'splits' output into two streams, such as
1028017a 151
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152 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
153 while (<STDIN>) {
154 print;
155 print OUT;
156 }
157 close OUT;
c9f97d15 158
6df41af2 159=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 160
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161(W misc) The pattern match (C<//>), substitution (C<s///>), and
162transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 163one of them to an array or a hash, it will convert the array or hash to
ac036724 164a scalar value (the length of an array, or the population info of a
165hash) and then work on that scalar value. This is probably not what
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166you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
167alternatives.
eb6e2d6f 168
6df41af2 169=item Arg too short for msgsnd
76cd736e 170
6df41af2 171(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 172
f86702cc 173=item Argument "%s" isn't numeric%s
a0d0e21e 174
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175(W numeric) The indicated string was fed as an argument to an operator
176that expected a numeric value instead. If you're fortunate the message
177will identify which operator was so unfortunate.
a0d0e21e 178
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179=item Argument list not closed for PerlIO layer "%s"
180
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181(W layer) When pushing a layer with arguments onto the Perl I/O
182system you forgot the ) that closes the argument list. (Layers
183take care of transforming data between external and internal
184representations.) Perl stopped parsing the layer list at this
185point and did not attempt to push this layer. If your program
186didn't explicitly request the failing operation, it may be the
187result of the value of the environment variable PERLIO.
b4581f09 188
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189=item Argument "%s" treated as 0 in increment (++)
190
191(W numeric) The indicated string was fed as an argument to the C<++>
192operator which expects either a number or a string matching
193C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
194Auto-decrement> for details.
195
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196=item assertion botched: %s
197
21b5e840 198(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 199
0eacef8e 200=item Assertion %s failed: file "%s", line %d
a0d0e21e 201
21b5e840 202(X) A general assertion failed. The file in question must be examined.
a0d0e21e 203
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204=item Assigning non-zero to $[ is no longer possible
205
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206(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
207the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 208
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209=item Assignment to both a list and a scalar
210
211(F) If you assign to a conditional operator, the 2nd and 3rd arguments
212must either both be scalars or both be lists. Otherwise Perl won't
213know which context to supply to the right side.
214
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215=item <> at require-statement should be quotes
216
217(F) You wrote C<< require <file> >> when you should have written
218C<require 'file'>.
219
2393f1b9 220=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 221
49293501 222(F) The failing code has attempted to get or set a key which is not in
2393f1b9 223the current set of allowed keys of a restricted hash.
49293501 224
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225=item Attempt to bless into a freed package
226
227(F) You wrote C<bless $foo> with one argument after somehow causing
228the current package to be freed. Perl cannot figure out what to
229do, so it throws up in hands in despair.
230
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231=item Attempt to bless into a reference
232
233(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 234the name of the package to bless the resulting object into. You've
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235supplied instead a reference to something: perhaps you wrote
236
237 bless $self, $proto;
238
239when you intended
240
241 bless $self, ref($proto) || $proto;
242
243If you actually want to bless into the stringified version
244of the reference supplied, you need to stringify it yourself, for
245example by:
246
247 bless $self, "$proto";
248
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249=item Attempt to clear deleted array
250
251(S debugging) An array was assigned to when it was being freed.
252Freed values are not supposed to be visible to Perl code. This
253can also happen if XS code calls C<av_clear> from a custom magic
254callback on the array.
255
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256=item Attempt to delete disallowed key '%s' from a restricted hash
257
258(F) The failing code attempted to delete from a restricted hash a key
259which is not in its key set.
260
261=item Attempt to delete readonly key '%s' from a restricted hash
262
263(F) The failing code attempted to delete a key whose value has been
264declared readonly from a restricted hash.
265
de42a5a9 266=item Attempt to free non-arena SV: 0x%x
a0d0e21e 267
f84fe999 268(S internal) All SV objects are supposed to be allocated from arenas
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269that will be garbage collected on exit. An SV was discovered to be
270outside any of those arenas.
a0d0e21e 271
12578ffb 272=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 273
f84fe999 274(S internal) Perl maintains a reference-counted internal table of
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275strings to optimize the storage and access of hash keys and other
276strings. This indicates someone tried to decrement the reference count
277of a string that can no longer be found in the table.
bbce6d69 278
7d5b40b4 279=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 280
f84fe999 281(S debugging) Mortalized values are supposed to be freed by the
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282free_tmps() routine. This indicates that something else is freeing the
283SV before the free_tmps() routine gets a chance, which means that the
284free_tmps() routine will be freeing an unreferenced scalar when it does
285try to free it.
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286
287=item Attempt to free unreferenced glob pointers
288
f84fe999 289(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 290
7d5b40b4 291=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 292
8f7e4d2c 293(S internal) Perl went to decrement the reference count of a scalar to
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294see if it would go to 0, and discovered that it had already gone to 0
295earlier, and should have been freed, and in fact, probably was freed.
296This could indicate that SvREFCNT_dec() was called too many times, or
297that SvREFCNT_inc() was called too few times, or that the SV was
298mortalized when it shouldn't have been, or that memory has been
299corrupted.
a0d0e21e 300
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301=item Attempt to pack pointer to temporary value
302
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303(W pack) You tried to pass a temporary value (like the result of a
304function, or a computed expression) to the "p" pack() template. This
305means the result contains a pointer to a location that could become
306invalid anytime, even before the end of the current statement. Use
307literals or global values as arguments to the "p" pack() template to
308avoid this warning.
84902520 309
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310=item Attempt to reload %s aborted.
311
312(F) You tried to load a file with C<use> or C<require> that failed to
313compile once already. Perl will not try to compile this file again
314unless you delete its entry from %INC. See L<perlfunc/require> and
315L<perlvar/%INC>.
316
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317=item Attempt to set length of freed array
318
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319(W misc) You tried to set the length of an array which has
320been freed. You can do this by storing a reference to the
321scalar representing the last index of an array and later
322assigning through that reference. For example
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323
324 $r = do {my @a; \$#a};
325 $$r = 503
326
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327=item Attempt to use reference as lvalue in substr
328
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329(W substr) You supplied a reference as the first argument to substr()
330used as an lvalue, which is pretty strange. Perhaps you forgot to
331dereference it first. See L<perlfunc/substr>.
b7a902f4 332
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333=item Attribute "locked" is deprecated
334
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335(D deprecated) You have used the attributes pragma to modify the
336"locked" attribute on a code reference. The :locked attribute is
337obsolete, has had no effect since 5005 threads were removed, and
338will be removed in a future release of Perl 5.
c32124fe 339
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340=item Attribute prototype(%s) discards earlier prototype attribute in same sub
341
342(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
343example. Since each sub can only have one prototype, the earlier
344declaration(s) are discarded while the last one is applied.
345
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346=item Attribute "unique" is deprecated
347
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348(D deprecated) You have used the attributes pragma to modify
349the "unique" attribute on an array, hash or scalar reference.
350The :unique attribute has had no effect since Perl 5.8.8, and
351will be removed in a future release of Perl 5.
f1a3ce43 352
ccce04a4
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353=item av_reify called on tied array
354
355(S debugging) This indicates that something went wrong and Perl got I<very>
356confused about C<@_> or C<@DB::args> being tied.
357
de42a5a9 358=item Bad arg length for %s, is %u, should be %d
a0d0e21e 359
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360(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
361or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 362S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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363S<sizeof(struct shmid_ds *)>.
364
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365=item Bad evalled substitution pattern
366
496a33f5 367(F) You've used the C</e> switch to evaluate the replacement for a
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368substitution, but perl found a syntax error in the code to evaluate,
369most likely an unexpected right brace '}'.
370
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371=item Bad filehandle: %s
372
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373(F) A symbol was passed to something wanting a filehandle, but the
374symbol has no filehandle associated with it. Perhaps you didn't do an
375open(), or did it in another package.
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376
377=item Bad free() ignored
378
be771a83 379(S malloc) An internal routine called free() on something that had never
fa816bf3 380been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 381setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 382
9ea8bc6d 383This message can be seen quite often with DB_File on systems with "hard"
6903afa2 384dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 385which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 386
aa689395
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387=item Bad hash
388
389(P) One of the internal hash routines was passed a null HV pointer.
390
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391=item Badly placed ()'s
392
393(A) You've accidentally run your script through B<csh> instead
394of Perl. Check the #! line, or manually feed your script into
395Perl yourself.
396
a7cb8dae 397=item Bad name after %s
a0d0e21e 398
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399(F) You started to name a symbol by using a package prefix, and then
400didn't finish the symbol. In particular, you can't interpolate outside
401of quotes, so
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402
403 $var = 'myvar';
404 $sym = mypack::$var;
405
406is not the same as
407
408 $var = 'myvar';
409 $sym = "mypack::$var";
410
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411=item Bad plugin affecting keyword '%s'
412
413(F) An extension using the keyword plugin mechanism violated the
414plugin API.
415
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416=item Bad realloc() ignored
417
6903afa2
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418(S malloc) An internal routine called realloc() on something that
419had never been malloc()ed in the first place. Mandatory, but can
420be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 421
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422=item Bad symbol for array
423
424(P) An internal request asked to add an array entry to something that
425wasn't a symbol table entry.
426
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427=item Bad symbol for dirhandle
428
429(P) An internal request asked to add a dirhandle entry to something
430that wasn't a symbol table entry.
431
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432=item Bad symbol for filehandle
433
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434(P) An internal request asked to add a filehandle entry to something
435that wasn't a symbol table entry.
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436
437=item Bad symbol for hash
438
439(P) An internal request asked to add a hash entry to something that
440wasn't a symbol table entry.
441
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442=item Bareword found in conditional
443
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444(W bareword) The compiler found a bareword where it expected a
445conditional, which often indicates that an || or && was parsed as part
446of the last argument of the previous construct, for example:
34d09196
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447
448 open FOO || die;
449
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450It may also indicate a misspelled constant that has been interpreted as
451a bareword:
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452
453 use constant TYPO => 1;
454 if (TYOP) { print "foo" }
455
456The C<strict> pragma is useful in avoiding such errors.
457
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458=item Bareword "%s" not allowed while "strict subs" in use
459
460(F) With "strict subs" in use, a bareword is only allowed as a
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461subroutine identifier, in curly brackets or to the left of the "=>"
462symbol. Perhaps you need to predeclare a subroutine?
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463
464=item Bareword "%s" refers to nonexistent package
465
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466(W bareword) You used a qualified bareword of the form C<Foo::>, but the
467compiler saw no other uses of that namespace before that point. Perhaps
468you need to predeclare a package?
6df41af2 469
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470=item BEGIN failed--compilation aborted
471
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472(F) An untrapped exception was raised while executing a BEGIN
473subroutine. Compilation stops immediately and the interpreter is
474exited.
a0d0e21e 475
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476=item BEGIN not safe after errors--compilation aborted
477
478(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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479implies a C<BEGIN {}>) after one or more compilation errors had already
480occurred. Since the intended environment for the C<BEGIN {}> could not
481be guaranteed (due to the errors), and since subsequent code likely
482depends on its correct operation, Perl just gave up.
68dc0745 483
c782d7ee 484=item \%d better written as $%d
6df41af2 485
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486(W syntax) Outside of patterns, backreferences live on as variables.
487The use of backslashes is grandfathered on the right-hand side of a
488substitution, but stylistically it's better to use the variable form
489because other Perl programmers will expect it, and it works better if
490there are more than 9 backreferences.
6df41af2 491
252aa082
JH
492=item Binary number > 0b11111111111111111111111111111111 non-portable
493
e476b1b5 494(W portable) The binary number you specified is larger than 2**32-1
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JH
495(4294967295) and therefore non-portable between systems. See
496L<perlport> for more on portability concerns.
252aa082 497
69282e91 498=item bind() on closed socket %s
a0d0e21e 499
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500(W closed) You tried to do a bind on a closed socket. Did you forget to
501check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 502
c289d2f7
JH
503=item binmode() on closed filehandle %s
504
505(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 506Check your control flow and number of arguments.
c289d2f7 507
c5a0f51a
JH
508=item Bit vector size > 32 non-portable
509
e476b1b5 510(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 511
043c750c 512=item Bizarre copy of %s
4633a7c4 513
be771a83 514(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 515copiable.
4633a7c4 516
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517=item Bizarre SvTYPE [%d]
518
434f489b 519(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
520encountered an invalid data type.
521
f675dbe5
CB
522=item Buffer overflow in prime_env_iter: %s
523
be771a83
GS
524(W internal) A warning peculiar to VMS. While Perl was preparing to
525iterate over %ENV, it encountered a logical name or symbol definition
526which was too long, so it was truncated to the string shown.
f675dbe5 527
a0d0e21e
LW
528=item Callback called exit
529
4929bf7b 530(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
531exited by calling exit.
532
6df41af2 533=item %s() called too early to check prototype
f675dbe5 534
be771a83
GS
535(W prototype) You've called a function that has a prototype before the
536parser saw a definition or declaration for it, and Perl could not check
537that the call conforms to the prototype. You need to either add an
538early prototype declaration for the subroutine in question, or move the
539subroutine definition ahead of the call to get proper prototype
540checking. Alternatively, if you are certain that you're calling the
541function correctly, you may put an ampersand before the name to avoid
542the warning. See L<perlsub>.
f675dbe5 543
56feebad
FC
544=item Calling POSIX::%s() is deprecated
545
546(D deprecated) You called a function whose use is deprecated. See
547the function's name in L<POSIX> for details.
548
49704364 549=item Cannot compress integer in pack
0258719b
NC
550
551(F) An argument to pack("w",...) was too large to compress. The BER
552compressed integer format can only be used with positive integers, and you
553attempted to compress Infinity or a very large number (> 1e308).
554See L<perlfunc/pack>.
555
49704364 556=item Cannot compress negative numbers in pack
0258719b
NC
557
558(F) An argument to pack("w",...) was negative. The BER compressed integer
559format can only be used with positive integers. See L<perlfunc/pack>.
560
5c1f4d79
NC
561=item Cannot convert a reference to %s to typeglob
562
6903afa2
FC
563(F) You manipulated Perl's symbol table directly, stored a reference
564in it, then tried to access that symbol via conventional Perl syntax.
565The access triggers Perl to autovivify that typeglob, but it there is
566no legal conversion from that type of reference to a typeglob.
5c1f4d79 567
4040665a 568=item Cannot copy to %s
ba2fdce6
NC
569
570(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 571be directly assigned to.
ba2fdce6 572
b5d97229
RGS
573=item Cannot find encoding "%s"
574
575(S io) You tried to apply an encoding that did not exist to a filehandle,
576either with open() or binmode().
577
7355df7e
FC
578=item Cannot set tied @DB::args
579
580(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
581is not supported. (Before this error was added, it used to crash.)
582
ce65bc73
FC
583=item Cannot tie unreifiable array
584
585(P) You somehow managed to call C<tie> on an array that does not
586keep a reference count on its arguments and cannot be made to
587do so. Such arrays are not even supposed to be accessible to
588Perl code, but are only used internally.
589
96ebfdd7
RK
590=item Can only compress unsigned integers in pack
591
592(F) An argument to pack("w",...) was not an integer. The BER compressed
593integer format can only be used with positive integers, and you attempted
594to compress something else. See L<perlfunc/pack>.
595
a0d0e21e
LW
596=item Can't bless non-reference value
597
598(F) Only hard references may be blessed. This is how Perl "enforces"
599encapsulation of objects. See L<perlobj>.
600
dc57907a
RGS
601=item Can't "break" in a loop topicalizer
602
0d863452 603(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 604a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
605
606=item Can't "break" outside a given block
dc57907a 607
0d863452
RH
608(F) You called C<break>, but you're not inside a C<given> block.
609
6df41af2
GS
610=item Can't call method "%s" on an undefined value
611
612(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
613object reference or package name contains an undefined value. Something
614like this will reproduce the error:
6df41af2
GS
615
616 $BADREF = undef;
617 process $BADREF 1,2,3;
618 $BADREF->process(1,2,3);
619
a0d0e21e
LW
620=item Can't call method "%s" on unblessed reference
621
54310121 622(F) A method call must know in what package it's supposed to run. It
be771a83
GS
623ordinarily finds this out from the object reference you supply, but you
624didn't supply an object reference in this case. A reference isn't an
625object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
626
627=item Can't call method "%s" without a package or object reference
628
629(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
630object reference or package name contains an expression that returns a
631defined value which is neither an object reference nor a package name.
72b5445b
GS
632Something like this will reproduce the error:
633
634 $BADREF = 42;
635 process $BADREF 1,2,3;
636 $BADREF->process(1,2,3);
637
dfe378f1
FC
638=item Can't call mro_isa_changed_in() on anonymous symbol table
639
640(P) Perl got confused as to whether a hash was a plain hash or a
641symbol table hash when trying to update @ISA caches.
642
2bf7e7b2
FC
643=item Can't call mro_method_changed_in() on anonymous symbol table
644
645(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
646not attached to the symbol table.
647
a0d0e21e
LW
648=item Can't chdir to %s
649
f703fc96 650(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
651that you can chdir to, possibly because it doesn't exist.
652
0545a864 653=item Can't check filesystem of script "%s" for nosuid
104d25b7 654
be771a83
GS
655(P) For some reason you can't check the filesystem of the script for
656nosuid.
104d25b7 657
22e74366 658=item Can't coerce %s to %s in %s
a0d0e21e
LW
659
660(F) Certain types of SVs, in particular real symbol table entries
55497cff 661(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
662say things like:
663
664 *foo += 1;
665
666You CAN say
667
668 $foo = *foo;
669 $foo += 1;
670
671but then $foo no longer contains a glob.
672
0d863452 673=item Can't "continue" outside a when block
dc57907a 674
0d863452
RH
675(F) You called C<continue>, but you're not inside a C<when>
676or C<default> block.
677
a0d0e21e
LW
678=item Can't create pipe mailbox
679
be771a83
GS
680(P) An error peculiar to VMS. The process is suffering from exhausted
681quotas or other plumbing problems.
a0d0e21e 682
eb64745e
GS
683=item Can't declare %s in "%s"
684
30c282f6
NC
685(F) Only scalar, array, and hash variables may be declared as "my", "our" or
686"state" variables. They must have ordinary identifiers as names.
a0d0e21e 687
fc7debfb
FC
688=item Can't "default" outside a topicalizer
689
690(F) You have used a C<default> block that is neither inside a
691C<foreach> loop nor a C<given> block. (Note that this error is
692issued on exit from the C<default> block, so you won't get the
693error if you use an explicit C<continue>.)
694
6df41af2
GS
695=item Can't do inplace edit: %s is not a regular file
696
be771a83 697(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 698a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 699
a0d0e21e
LW
700=item Can't do inplace edit on %s: %s
701
be771a83
GS
702(S inplace) The creation of the new file failed for the indicated
703reason.
a0d0e21e 704
54310121 705=item Can't do inplace edit without backup
a0d0e21e 706
be771a83
GS
707(F) You're on a system such as MS-DOS that gets confused if you try
708reading from a deleted (but still opened) file. You have to say
709C<-i.bak>, or some such.
a0d0e21e 710
10f9c03d 711=item Can't do inplace edit: %s would not be unique
a0d0e21e 712
e476b1b5 713(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
714characters and Perl was unable to create a unique filename during
715inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 716
a0d0e21e
LW
717=item Can't do waitpid with flags
718
be771a83
GS
719(F) This machine doesn't have either waitpid() or wait4(), so only
720waitpid() without flags is emulated.
a0d0e21e 721
a0d0e21e
LW
722=item Can't emulate -%s on #! line
723
be771a83
GS
724(F) The #! line specifies a switch that doesn't make sense at this
725point. For example, it'd be kind of silly to put a B<-x> on the #!
726line.
a0d0e21e 727
1109a392
MHM
728=item Can't %s %s-endian %ss on this platform
729
730(F) Your platform's byte-order is neither big-endian nor little-endian,
731or it has a very strange pointer size. Packing and unpacking big- or
732little-endian floating point values and pointers may not be possible.
733See L<perlfunc/pack>.
734
a0d0e21e
LW
735=item Can't exec "%s": %s
736
d1be9408 737(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
738named program for the indicated reason. Typical reasons include: the
739permissions were wrong on the file, the file wasn't found in
740C<$ENV{PATH}>, the executable in question was compiled for another
741architecture, or the #! line in a script points to an interpreter that
742can't be run for similar reasons. (Or maybe your system doesn't support
743#! at all.)
a0d0e21e
LW
744
745=item Can't exec %s
746
be771a83
GS
747(F) Perl was trying to execute the indicated program for you because
748that's what the #! line said. If that's not what you wanted, you may
749need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
750
751=item Can't execute %s
752
be771a83
GS
753(F) You used the B<-S> switch, but the copies of the script to execute
754found in the PATH did not have correct permissions.
2a92aaa0 755
6df41af2 756=item Can't find an opnumber for "%s"
2a92aaa0 757
be771a83
GS
758(F) A string of a form C<CORE::word> was given to prototype(), but there
759is no builtin with the name C<word>.
6df41af2 760
56ca2fc0
JH
761=item Can't find %s character property "%s"
762
763(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 764could not be found. Maybe you misspelled the name of the property?
e1b711da 765See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 766for a complete list of available official properties.
56ca2fc0 767
6df41af2
GS
768=item Can't find label %s
769
be771a83
GS
770(F) You said to goto a label that isn't mentioned anywhere that it's
771possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
772
773=item Can't find %s on PATH
774
be771a83
GS
775(F) You used the B<-S> switch, but the script to execute could not be
776found in the PATH.
a0d0e21e 777
6df41af2 778=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 779
be771a83
GS
780(F) You used the B<-S> switch, but the script to execute could not be
781found in the PATH, or at least not with the correct permissions. The
782script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
783
784=item Can't find string terminator %s anywhere before EOF
785
be771a83
GS
786(F) Perl strings can stretch over multiple lines. This message means
787that the closing delimiter was omitted. Because bracketed quotes count
788nesting levels, the following is missing its final parenthesis:
a0d0e21e 789
fb73857a
PP
790 print q(The character '(' starts a side comment.);
791
97b3d10f 792If you're getting this error from a here-document, you may have
b6b8cb97
FC
793included unseen whitespace before or after your closing tag or there
794may not be a linebreak after it. A good programmer's editor will have
795a way to help you find these characters (or lack of characters). See
796L<perlop> for the full details on here-documents.
a0d0e21e 797
660a4616
ST
798=item Can't find Unicode property definition "%s"
799
5f8ad6b6
FC
800(F) You may have tried to use C<\p> which means a Unicode
801property (for example C<\p{Lu}> matches all uppercase
fa816bf3 802letters). If you did mean to use a Unicode property, see
e1b711da 803L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 804for a complete list of available properties. If you didn't
fa816bf3
FC
805mean to use a Unicode property, escape the C<\p>, either by
806C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 807until C<\E>).
660a4616 808
b3647a36 809=item Can't fork: %s
a0d0e21e 810
be771a83
GS
811(F) A fatal error occurred while trying to fork while opening a
812pipeline.
a0d0e21e 813
b3647a36
SR
814=item Can't fork, trying again in 5 seconds
815
c973c02e 816(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
817after five seconds.
818
748a9306
LW
819=item Can't get filespec - stale stat buffer?
820
be771a83
GS
821(S) A warning peculiar to VMS. This arises because of the difference
822between access checks under VMS and under the Unix model Perl assumes.
823Under VMS, access checks are done by filename, rather than by bits in
824the stat buffer, so that ACLs and other protections can be taken into
825account. Unfortunately, Perl assumes that the stat buffer contains all
826the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 827the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
828the device name and FID present in the stat buffer, but this works only
829if you haven't made a subsequent call to the CRTL stat() routine,
830because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
831appears, the name lookup failed, and the access-checking routine gave up
832and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
833routine knows about the Perl C<stat> operator and file tests, so you
834shouldn't ever see this warning in response to a Perl command; it arises
835only if some internal code takes stat buffers lightly.)
748a9306 836
a0d0e21e
LW
837=item Can't get pipe mailbox device name
838
be771a83
GS
839(P) An error peculiar to VMS. After creating a mailbox to act as a
840pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
841
842=item Can't get SYSGEN parameter value for MAXBUF
843
748a9306
LW
844(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
845mailbox buffers to be, and didn't get an answer.
a0d0e21e 846
6df41af2 847=item Can't "goto" into the middle of a foreach loop
a0d0e21e 848
be771a83
GS
849(F) A "goto" statement was executed to jump into the middle of a foreach
850loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
851
852=item Can't "goto" out of a pseudo block
853
be771a83
GS
854(F) A "goto" statement was executed to jump out of what might look like
855a block, except that it isn't a proper block. This usually occurs if
856you tried to jump out of a sort() block or subroutine, which is a no-no.
857See L<perlfunc/goto>.
a0d0e21e 858
5a25739d
FC
859=item Can't goto subroutine from an eval-%s
860
861(F) The "goto subroutine" call can't be used to jump out of an eval
862"string" or block.
863
9850bf21 864=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 865
9850bf21
RH
866(F) The "goto subroutine" call can't be used to jump out of the
867comparison sub for a sort(), or from a similar callback (such
868as the reduce() function in List::Util).
869
6df41af2
GS
870=item Can't goto subroutine outside a subroutine
871
be771a83
GS
872(F) The deeply magical "goto subroutine" call can only replace one
873subroutine call for another. It can't manufacture one out of whole
874cloth. In general you should be calling it out of only an AUTOLOAD
875routine anyway. See L<perlfunc/goto>.
6df41af2 876
0b5b802d
GS
877=item Can't ignore signal CHLD, forcing to default
878
be771a83
GS
879(W signal) Perl has detected that it is being run with the SIGCHLD
880signal (sometimes known as SIGCLD) disabled. Since disabling this
881signal will interfere with proper determination of exit status of child
882processes, Perl has reset the signal to its default value. This
883situation typically indicates that the parent program under which Perl
884may be running (e.g. cron) is being very careless.
0b5b802d 885
e2c0f81f
DG
886=item Can't kill a non-numeric process ID
887
888(F) Process identifiers must be (signed) integers. It is a fatal error to
889attempt to kill() an undefined, empty-string or otherwise non-numeric
890process identifier.
891
6df41af2 892=item Can't "last" outside a loop block
4633a7c4 893
6df41af2 894(F) A "last" statement was executed to break out of the current block,
be771a83
GS
895except that there's this itty bitty problem called there isn't a current
896block. Note that an "if" or "else" block doesn't count as a "loopish"
897block, as doesn't a block given to sort(), map() or grep(). You can
898usually double the curlies to get the same effect though, because the
899inner curlies will be considered a block that loops once. See
900L<perlfunc/last>.
4633a7c4 901
2c7d6b9c
RGS
902=item Can't linearize anonymous symbol table
903
904(F) Perl tried to calculate the method resolution order (MRO) of a
905package, but failed because the package stash has no name.
906
b8170e59
JB
907=item Can't load '%s' for module %s
908
6903afa2
FC
909(F) The module you tried to load failed to load a dynamic extension.
910This may either mean that you upgraded your version of perl to one
911that is incompatible with your old dynamic extensions (which is known
912to happen between major versions of perl), or (more likely) that your
913dynamic extension was built against an older version of the library
914that is installed on your system. You may need to rebuild your old
915dynamic extensions.
b8170e59 916
748a9306
LW
917=item Can't localize lexical variable %s
918
2ba9eb46 919(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
920lexical variable using "my" or "state". This is not allowed. If you
921want to localize a package variable of the same name, qualify it with
922the package name.
748a9306 923
6df41af2 924=item Can't localize through a reference
4727527e 925
6df41af2
GS
926(F) You said something like C<local $$ref>, which Perl can't currently
927handle, because when it goes to restore the old value of whatever $ref
be771a83 928pointed to after the scope of the local() is finished, it can't be sure
64977eb6 929that $ref will still be a reference.
4727527e 930
ea071790 931=item Can't locate %s
ec889f3a 932
fa816bf3
FC
933(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
934Perl looks for the file in all the locations mentioned in @INC, unless
935the file name included the full path to the file. Perhaps you need
936to set the PERL5LIB or PERL5OPT environment variable to say where the
937extra library is, or maybe the script needs to add the library name
be771a83
GS
938to @INC. Or maybe you just misspelled the name of the file. See
939L<perlfunc/require> and L<lib>.
a0d0e21e 940
6df41af2
GS
941=item Can't locate auto/%s.al in @INC
942
be771a83
GS
943(F) A function (or method) was called in a package which allows
944autoload, but there is no function to autoload. Most probable causes
945are a misprint in a function/method name or a failure to C<AutoSplit>
946the file, say, by doing C<make install>.
6df41af2 947
b8170e59
JB
948=item Can't locate loadable object for module %s in @INC
949
950(F) The module you loaded is trying to load an external library, like
d70d8e57 951for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
952unable to locate this library. See L<DynaLoader>.
953
a0d0e21e
LW
954=item Can't locate object method "%s" via package "%s"
955
956(F) You called a method correctly, and it correctly indicated a package
957functioning as a class, but that package doesn't define that particular
2ba9eb46 958method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
959
960=item Can't locate package %s for @%s::ISA
961
be771a83
GS
962(W syntax) The @ISA array contained the name of another package that
963doesn't seem to exist.
a0d0e21e 964
2f7da168
RK
965=item Can't locate PerlIO%s
966
967(F) You tried to use in open() a PerlIO layer that does not exist,
968e.g. open(FH, ">:nosuchlayer", "somefile").
969
f4ad53f4 970=item Can't make list assignment to %ENV on this system
3e3baf6d 971
be771a83
GS
972(F) List assignment to %ENV is not supported on some systems, notably
973VMS.
3e3baf6d 974
cd40cd58
NC
975=item Can't make loaded symbols global on this platform while loading %s
976
ff9c1ae8 977(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
978that symbols from the stated file are made available globally within the
979process, but that functionality is not available on this platform. Whilst
980the module likely will still work, this may prevent the perl interpreter
981from loading other XS-based extensions which need to link directly to
982functions defined in the C or XS code in the stated file.
983
a0d0e21e
LW
984=item Can't modify %s in %s
985
be771a83
GS
986(F) You aren't allowed to assign to the item indicated, or otherwise try
987to change it, such as with an auto-increment.
a0d0e21e 988
54310121 989=item Can't modify nonexistent substring
a0d0e21e
LW
990
991(P) The internal routine that does assignment to a substr() was handed
992a NULL.
993
6df41af2
GS
994=item Can't modify non-lvalue subroutine call
995
996(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 997such. See L<perlsub/"Lvalue subroutines">.
6df41af2 998
5f05dabc 999=item Can't msgrcv to read-only var
a0d0e21e 1000
5f05dabc 1001(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1002buffer.
1003
6df41af2
GS
1004=item Can't "next" outside a loop block
1005
1006(F) A "next" statement was executed to reiterate the current block, but
1007there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1008count as a "loopish" block, as doesn't a block given to sort(), map() or
1009grep(). You can usually double the curlies to get the same effect
1010though, because the inner curlies will be considered a block that loops
1011once. See L<perlfunc/next>.
6df41af2 1012
a0d0e21e
LW
1013=item Can't open %s: %s
1014
c47ff5f1 1015(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1016filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1017switches, or explicitly, failed for the indicated reason. Usually
1018this is because you don't have read permission for a file which
1019you named on the command line.
1020
1021(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1022your operating system's equivalent) could not be opened.
a0d0e21e 1023
9a869a14
RGS
1024=item Can't open a reference
1025
1026(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1027using the 3-arg open() syntax:
9a869a14
RGS
1028
1029 open FH, '>', $ref;
1030
1031but your version of perl is compiled without perlio, and this form of
1032open is not supported.
1033
a0d0e21e
LW
1034=item Can't open bidirectional pipe
1035
be771a83
GS
1036(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1037You can try any of several modules in the Perl library to do this, such
1038as IPC::Open2. Alternately, direct the pipe's output to a file using
1039">", and then read it in under a different file handle.
a0d0e21e 1040
748a9306
LW
1041=item Can't open error file %s as stderr
1042
be771a83
GS
1043(F) An error peculiar to VMS. Perl does its own command line
1044redirection, and couldn't open the file specified after '2>' or '2>>' on
1045the command line for writing.
748a9306
LW
1046
1047=item Can't open input file %s as stdin
1048
be771a83
GS
1049(F) An error peculiar to VMS. Perl does its own command line
1050redirection, and couldn't open the file specified after '<' on the
1051command line for reading.
748a9306
LW
1052
1053=item Can't open output file %s as stdout
1054
be771a83
GS
1055(F) An error peculiar to VMS. Perl does its own command line
1056redirection, and couldn't open the file specified after '>' or '>>' on
1057the command line for writing.
748a9306
LW
1058
1059=item Can't open output pipe (name: %s)
1060
be771a83
GS
1061(P) An error peculiar to VMS. Perl does its own command line
1062redirection, and couldn't open the pipe into which to send data destined
1063for stdout.
748a9306 1064
3b1cf97d 1065=item Can't open perl script "%s": %s
a0d0e21e
LW
1066
1067(F) The script you specified can't be opened for the indicated reason.
1068
fa3aa65a
JC
1069If you're debugging a script that uses #!, and normally relies on the
1070shell's $PATH search, the -S option causes perl to do that search, so
1071you don't have to type the path or C<`which $scriptname`>.
1072
6df41af2
GS
1073=item Can't read CRTL environ
1074
1075(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1076from the CRTL's internal environment array and discovered the array was
1077missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1078or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1079searched.
6df41af2 1080
6df41af2
GS
1081=item Can't "redo" outside a loop block
1082
1083(F) A "redo" statement was executed to restart the current block, but
1084there isn't a current block. Note that an "if" or "else" block doesn't
1085count as a "loopish" block, as doesn't a block given to sort(), map()
1086or grep(). You can usually double the curlies to get the same effect
1087though, because the inner curlies will be considered a block that
1088loops once. See L<perlfunc/redo>.
1089
64977eb6 1090=item Can't remove %s: %s, skipping file
10f9c03d 1091
be771a83
GS
1092(S inplace) You requested an inplace edit without creating a backup
1093file. Perl was unable to remove the original file to replace it with
1094the modified file. The file was left unmodified.
10f9c03d 1095
a0d0e21e
LW
1096=item Can't rename %s to %s: %s, skipping file
1097
e476b1b5 1098(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1099probably because you don't have write permission to the directory.
a0d0e21e 1100
748a9306
LW
1101=item Can't reopen input pipe (name: %s) in binary mode
1102
be771a83
GS
1103(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1104to reopen it to accept binary data. Alas, it failed.
748a9306 1105
4f12ec0e
FC
1106=item Can't reset %ENV on this system
1107
1108(F) You called C<reset('E')> or similar, which tried to reset
1109all variables in the current package beginning with "E". In
1110the main package, that includes %ENV. Resetting %ENV is not
1111supported on some systems, notably VMS.
1112
fe13d51d 1113=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1114
1fa582fa
FC
1115(F)(P) Error resolving overloading specified by a method name (as
1116opposed to a subroutine reference): no such method callable via the
1117package. If the method name is C<???>, this is an internal error.
6df41af2 1118
cd06dffe
GS
1119=item Can't return %s from lvalue subroutine
1120
be771a83
GS
1121(F) Perl detected an attempt to return illegal lvalues (such as
1122temporary or readonly values) from a subroutine used as an lvalue. This
1123is not allowed.
cd06dffe 1124
96ebfdd7
RK
1125=item Can't return outside a subroutine
1126
1127(F) The return statement was executed in mainline code, that is, where
1128there was no subroutine call to return out of. See L<perlsub>.
1129
78f9721b
SM
1130=item Can't return %s to lvalue scalar context
1131
6903afa2
FC
1132(F) You tried to return a complete array or hash from an lvalue
1133subroutine, but you called the subroutine in a way that made Perl
1134think you meant to return only one value. You probably meant to
1135write parentheses around the call to the subroutine, which tell
1136Perl that the call should be in list context.
78f9721b 1137
a0d0e21e
LW
1138=item Can't stat script "%s"
1139
be771a83
GS
1140(P) For some reason you can't fstat() the script even though you have it
1141open already. Bizarre.
a0d0e21e 1142
a0d0e21e
LW
1143=item Can't take log of %g
1144
fb73857a 1145(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1146negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1147standard with Perl, though, if you really want to do that for the
1148negative numbers.
a0d0e21e
LW
1149
1150=item Can't take sqrt of %g
1151
1152(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1153negative number. There's a Math::Complex package that comes standard
1154with Perl, though, if you really want to do that.
a0d0e21e
LW
1155
1156=item Can't undef active subroutine
1157
1158(F) You can't undefine a routine that's currently running. You can,
1159however, redefine it while it's running, and you can even undef the
1160redefined subroutine while the old routine is running. Go figure.
1161
c81225bc 1162=item Can't upgrade %s (%d) to %d
a0d0e21e 1163
be771a83
GS
1164(P) The internal sv_upgrade routine adds "members" to an SV, making it
1165into a more specialized kind of SV. The top several SV types are so
1166specialized, however, that they cannot be interconverted. This message
1167indicates that such a conversion was attempted.
a0d0e21e 1168
6651ba0b
FC
1169=item Can't use '%c' after -mname
1170
1171(F) You tried to call perl with the B<-m> switch, but you put something
1172other than "=" after the module name.
1173
1f1ec7b5
KW
1174=item Can't use a hash as a reference
1175
1176(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1177C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1178<= 5.22.0 used to allow this syntax, but shouldn't
1179have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1180
1181=item Can't use an array as a reference
1182
1183(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1184C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1185used to allow this syntax, but shouldn't have. This
1186was deprecated in perl 5.6.1.
1f1ec7b5 1187
1db89ea5
BS
1188=item Can't use anonymous symbol table for method lookup
1189
e27ad1f2 1190(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1191table that doesn't have a name. Symbol tables can become anonymous
1192for example by undefining stashes: C<undef %Some::Package::>.
1193
96ebfdd7
RK
1194=item Can't use an undefined value as %s reference
1195
1196(F) A value used as either a hard reference or a symbolic reference must
1197be a defined value. This helps to delurk some insidious errors.
1198
6df41af2
GS
1199=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1200
be771a83
GS
1201(F) Only hard references are allowed by "strict refs". Symbolic
1202references are disallowed. See L<perlref>.
6df41af2 1203
90b75b61 1204=item Can't use %! because Errno.pm is not available
1d2dff63 1205
20561843 1206(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1207Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1208provide symbolic names for C<$!> errno values.
1209
1109a392
MHM
1210=item Can't use both '<' and '>' after type '%c' in %s
1211
1212(F) A type cannot be forced to have both big-endian and little-endian
1213byte-order at the same time, so this combination of modifiers is not
1214allowed. See L<perlfunc/pack>.
1215
e35475de
KW
1216=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1217
1218(F) defined() is not useful on arrays because it
1219checks for an undefined I<scalar> value. If you want to see if the
1220array is empty, just use C<if (@array) { # not empty }> for example.
1221
1222=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1223
1224(F) C<defined()> is not usually right on hashes.
1225
1226Although C<defined %hash> is false on a plain not-yet-used hash, it
1227becomes true in several non-obvious circumstances, including iterators,
1228weak references, stash names, even remaining true after C<undef %hash>.
1229These things make C<defined %hash> fairly useless in practice, so it now
1230generates a fatal error.
1231
1232If a check for non-empty is what you wanted then just put it in boolean
1233context (see L<perldata/Scalar values>):
1234
1235 if (%hash) {
1236 # not empty
1237 }
1238
1239If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1240variable exists then that's never really been reliable, and isn't
1241a good way to enquire about the features of a package, or whether
1242it's loaded, etc.
1243
6df41af2
GS
1244=item Can't use %s for loop variable
1245
be771a83
GS
1246(F) Only a simple scalar variable may be used as a loop variable on a
1247foreach.
6df41af2 1248
aab6a793 1249=item Can't use global %s in "%s"
6df41af2 1250
be771a83
GS
1251(F) You tried to declare a magical variable as a lexical variable. This
1252is not allowed, because the magic can be tied to only one location
1253(namely the global variable) and it would be incredibly confusing to
1254have variables in your program that looked like magical variables but
6df41af2
GS
1255weren't.
1256
6d3b25aa
RGS
1257=item Can't use '%c' in a group with different byte-order in %s
1258
1259(F) You attempted to force a different byte-order on a type
1260that is already inside a group with a byte-order modifier.
1261For example you cannot force little-endianness on a type that
1262is inside a big-endian group.
1263
c07a80fd
PP
1264=item Can't use "my %s" in sort comparison
1265
1266(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1267You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1268and the variable had earlier been declared as a lexical variable.
1269Either qualify the sort variable with the package name, or rename the
1270lexical variable.
1271
a0d0e21e
LW
1272=item Can't use %s ref as %s ref
1273
1274(F) You've mixed up your reference types. You have to dereference a
1275reference of the type needed. You can use the ref() function to
1276test the type of the reference, if need be.
1277
748a9306 1278=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1279
5e634d20
FC
1280=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1281
b41bf23f
FC
1282(F) You've told Perl to dereference a string, something which
1283C<use strict> blocks to prevent it happening accidentally. See
1284L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1285in a double-quoted string immediately before interpolating a variable,
1286for example in C<"user @$twitter_id">, which says to treat the contents
1287of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1288symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1289
748a9306
LW
1290=item Can't use subscript on %s
1291
1292(F) The compiler tried to interpret a bracketed expression as a
1293subscript. But to the left of the brackets was an expression that
209e7cf1 1294didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1295
6df41af2
GS
1296=item Can't use \%c to mean $%c in expression
1297
75b44862
GS
1298(W syntax) In an ordinary expression, backslash is a unary operator that
1299creates a reference to its argument. The use of backslash to indicate a
1300backreference to a matched substring is valid only as part of a regular
be771a83
GS
1301expression pattern. Trying to do this in ordinary Perl code produces a
1302value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1303instead.
6df41af2 1304
810b8aa5
GS
1305=item Can't weaken a nonreference
1306
1307(F) You attempted to weaken something that was not a reference. Only
1308references can be weakened.
1309
fc7debfb
FC
1310=item Can't "when" outside a topicalizer
1311
1312(F) You have used a when() block that is neither inside a C<foreach>
1313loop nor a C<given> block. (Note that this error is issued on exit
1314from the C<when> block, so you won't get the error if the match fails,
1315or if you use an explicit C<continue>.)
1316
5f05dabc 1317=item Can't x= to read-only value
a0d0e21e 1318
be771a83
GS
1319(F) You tried to repeat a constant value (often the undefined value)
1320with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1321Perhaps you need to copy the value to a temporary, and repeat that.
1322
a04e6aad 1323=item Character following "\c" must be printable ASCII
f9d13529 1324
7357bd17 1325(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1326
727b6379 1327Note that ASCII characters that don't map to control characters are
7357bd17 1328discouraged, and will generate the warning (when enabled)
727b6379 1329L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1330
f337b084 1331=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1332
1333(W pack) You said
1334
1335 pack("C", $x)
1336
1337where $x is either less than 0 or more than 255; the C<"C"> format is
1338only for encoding native operating system characters (ASCII, EBCDIC,
1339and so on) and not for Unicode characters, so Perl behaved as if you meant
1340
1341 pack("C", $x & 255)
1342
1343If you actually want to pack Unicode codepoints, use the C<"U"> format
1344instead.
1345
f337b084 1346=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1347
1348(W pack) You said
1349
1350 pack("c", $x)
1351
1352where $x is either less than -128 or more than 127; the C<"c"> format
1353is only for encoding native operating system characters (ASCII, EBCDIC,
1354and so on) and not for Unicode characters, so Perl behaved as if you meant
1355
1356 pack("c", $x & 255);
1357
1358If you actually want to pack Unicode codepoints, use the C<"U"> format
1359instead.
1360
f337b084
TH
1361=item Character in '%c' format wrapped in unpack
1362
1363(W unpack) You tried something like
1364
1365 unpack("H", "\x{2a1}")
1366
1a147d38 1367where the format expects to process a byte (a character with a value
6903afa2
FC
1368below 256), but a higher value was provided instead. Perl uses the
1369value modulus 256 instead, as if you had provided:
f337b084
TH
1370
1371 unpack("H", "\x{a1}")
1372
5a25739d
FC
1373=item Character in 'W' format wrapped in pack
1374
1375(W pack) You said
1376
1377 pack("U0W", $x)
1378
1379where $x is either less than 0 or more than 255. However, C<U0>-mode
1380expects all values to fall in the interval [0, 255], so Perl behaved
1381as if you meant:
1382
1383 pack("U0W", $x & 255)
1384
f337b084
TH
1385=item Character(s) in '%c' format wrapped in pack
1386
1387(W pack) You tried something like
1388
1389 pack("u", "\x{1f3}b")
1390
1a147d38 1391where the format expects to process a sequence of bytes (character with a
6903afa2 1392value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1393uses the character values modulus 256 instead, as if you had provided:
1394
1395 pack("u", "\x{f3}b")
1396
1397=item Character(s) in '%c' format wrapped in unpack
1398
1399(W unpack) You tried something like
1400
1401 unpack("s", "\x{1f3}b")
1402
1a147d38 1403where the format expects to process a sequence of bytes (character with a
6903afa2 1404value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1405uses the character values modulus 256 instead, as if you had provided:
1406
1407 unpack("s", "\x{f3}b")
1408
f51551f7
FC
1409=item charnames alias definitions may not contain a sequence of multiple spaces
1410
1411(F) You defined a character name which had multiple space characters
1412in a row. Change them to single spaces. Usually these names are
1413defined in the C<:alias> import argument to C<use charnames>, but they
1414could be defined by a translator installed into C<$^H{charnames}>. See
1415L<charnames/CUSTOM ALIASES>.
1416
1417=item charnames alias definitions may not contain trailing white-space
1418
1419(F) You defined a character name which ended in a space
1420character. Remove the trailing space(s). Usually these names are
1421defined in the C<:alias> import argument to C<use charnames>, but they
1422could be defined by a translator installed into C<$^H{charnames}>.
1423See L<charnames/CUSTOM ALIASES>.
1424
1425=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1426
1427(D deprecated, regexp) The \C character class is deprecated, and will
1428become a compile-time error in a future release of perl (tentatively
1429v5.24). This construct allows you to match a single byte of what makes up
1430a multi-byte single UTF8 character, and breaks encapsulation. It is
1431currently also very buggy. If you really need to process the individual
1432bytes, you probably want to convert your string to one where each
1433underlying byte is stored as a character, with utf8::encode().
1434
f866a7cd
FC
1435=item "\c%c" is more clearly written simply as "%s"
1436
1437(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1438non-printable characters. You used it for a printable one, which is better
1439written as simply itself, perhaps preceded by a backslash for non-word
1440characters.
1441
6651ba0b
FC
1442=item Cloning substitution context is unimplemented
1443
1444(F) Creating a new thread inside the C<s///> operator is not supported.
1445
abc7ecad
SP
1446=item closedir() attempted on invalid dirhandle %s
1447
1448(W io) The dirhandle you tried to close is either closed or not really
1449a dirhandle. Check your control flow.
1450
5a25739d
FC
1451=item close() on unopened filehandle %s
1452
1453(W unopened) You tried to close a filehandle that was never opened.
1454
541ed3a9
FC
1455=item Closure prototype called
1456
1457(F) If a closure has attributes, the subroutine passed to an attribute
1458handler is the prototype that is cloned when a new closure is created.
1459This subroutine cannot be called.
1460
49704364
LW
1461=item Code missing after '/'
1462
6903afa2
FC
1463(F) You had a (sub-)template that ends with a '/'. There must be
1464another template code following the slash. See L<perlfunc/pack>.
49704364 1465
5a25739d
FC
1466=item Code point 0x%X is not Unicode, may not be portable
1467
2d88a86a 1468(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1469of U+10FFFF.
1470
1471Perl allows strings to contain a superset of Unicode code points, up
1472to the limit of what is storable in an unsigned integer on your system,
1473but these may not be accepted by other languages/systems. At one time,
1474it was legal in some standards to have code points up to 0x7FFF_FFFF,
1475but not higher. Code points above 0xFFFF_FFFF require larger than a
147632 bit word.
0876b9a0 1477
6df41af2
GS
1478=item %s: Command not found
1479
a892b81a 1480(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1481instead of Perl. Check the #! line, or manually feed your script into
1482Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1483
1484 #!/usr/bin/perl -w
6df41af2 1485
7a2e2cd6
PP
1486=item Compilation failed in require
1487
1488(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1489Perl uses this generic message when none of the errors that it
1490encountered were severe enough to halt compilation immediately.
7a2e2cd6 1491
c3464db5
DD
1492=item Complex regular subexpression recursion limit (%d) exceeded
1493
be771a83
GS
1494(W regexp) The regular expression engine uses recursion in complex
1495situations where back-tracking is required. Recursion depth is limited
1496to 32766, or perhaps less in architectures where the stack cannot grow
1497arbitrarily. ("Simple" and "medium" situations are handled without
1498recursion and are not subject to a limit.) Try shortening the string
1499under examination; looping in Perl code (e.g. with C<while>) rather than
1500in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1501that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1502on I<Mastering Regular Expressions>.)
c3464db5 1503
69282e91 1504=item connect() on closed socket %s
a0d0e21e 1505
be771a83
GS
1506(W closed) You tried to do a connect on a closed socket. Did you forget
1507to check the return value of your socket() call? See
1508L<perlfunc/connect>.
a0d0e21e 1509
e21e7c6a
FC
1510=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1511
1512(F) The subroutine registered to handle constant overloading
1513(see L<overload>) or a custom charnames handler (see
1514L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1515
1516=item Constant(%s): $^H{%s} is not defined
1517
1518(F) The parser found inconsistencies while attempting to define an
1519overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1520L<overload> pragma?
e21e7c6a 1521
779c5bc9
GS
1522=item Constant is not %s reference
1523
1524(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1525is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1526The message indicates the type of reference that was expected. This
be771a83 1527usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1528See L<perlsub/"Constant Functions"> and L<constant>.
1529
4cee8e80
CS
1530=item Constant subroutine %s redefined
1531
aeb94125
FC
1532(W redefine)(S) You redefined a subroutine which had previously
1533been eligible for inlining. See L<perlsub/"Constant Functions">
1534for commentary and workarounds.
4cee8e80 1535
9607fc9c
PP
1536=item Constant subroutine %s undefined
1537
be771a83
GS
1538(W misc) You undefined a subroutine which had previously been eligible
1539for inlining. See L<perlsub/"Constant Functions"> for commentary and
1540workarounds.
9607fc9c 1541
5a25739d
FC
1542=item Constant(%s) unknown
1543
1544(F) The parser found inconsistencies either while attempting
1545to define an overloaded constant, or when trying to find the
1546character name specified in the C<\N{...}> escape. Perhaps you
1547forgot to load the corresponding L<overload> pragma?.
1548
e7ea3e70
IZ
1549=item Copy method did not return a reference
1550
6903afa2 1551(F) The method which overloads "=" is buggy. See
13a2d996 1552L<overload/Copy Constructor>.
e7ea3e70 1553
4aaa4757
FC
1554=item &CORE::%s cannot be called directly
1555
1556(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1557with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1558in this package cannot yet be called that way, but must be
1559called as barewords. Something like this will work:
1560
1561 BEGIN { *shove = \&CORE::push; }
1562 shove @array, 1,2,3; # pushes on to @array
1563
6798c92b
GS
1564=item CORE::%s is not a keyword
1565
1566(F) The CORE:: namespace is reserved for Perl keywords.
1567
675fa9ff
FC
1568=item Corrupted regexp opcode %d > %d
1569
1570(P) This is either an error in Perl, or, if you're using
1571one, your L<custom regular expression engine|perlreapi>. If not the
1572latter, report the problem through the L<perlbug> utility.
1573
a0d0e21e
LW
1574=item corrupted regexp pointers
1575
1576(P) The regular expression engine got confused by what the regular
1577expression compiler gave it.
1578
1579=item corrupted regexp program
1580
be771a83
GS
1581(P) The regular expression engine got passed a regexp program without a
1582valid magic number.
a0d0e21e 1583
de42a5a9 1584=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1585
1586(P) The malloc package that comes with Perl had an internal failure.
1587
49704364
LW
1588=item Count after length/code in unpack
1589
1590(F) You had an unpack template indicating a counted-length string, but
1591you have also specified an explicit size for the string. See
1592L<perlfunc/pack>.
1593
f2cccb4c
KW
1594=for comment
1595The following are used in lib/diagnostics.t for testing two =items that
1596share the same description. Changes here need to be propagated to there
1597
6651ba0b
FC
1598=item Deep recursion on anonymous subroutine
1599
a0d0e21e
LW
1600=item Deep recursion on subroutine "%s"
1601
be771a83
GS
1602(W recursion) This subroutine has called itself (directly or indirectly)
1603100 times more than it has returned. This probably indicates an
1604infinite recursion, unless you're writing strange benchmark programs, in
1605which case it indicates something else.
a0d0e21e 1606
aad1d01f
NC
1607This threshold can be changed from 100, by recompiling the F<perl> binary,
1608setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1609
e0e4a6e3
FC
1610=item (?(DEFINE)....) does not allow branches in regex; marked by
1611S<<-- HERE> in m/%s/
bcb95744 1612
6903afa2 1613(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1614most likely cause of this error is that you left out a parenthesis inside
1615of the C<....> part.
1616
9e3ec65c 1617The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1618discovered.
1619
62658f4d
PM
1620=item %s defines neither package nor VERSION--version check failed
1621
1622(F) You said something like "use Module 42" but in the Module file
1623there are neither package declarations nor a C<$VERSION>.
1624
36447869
FC
1625=item delete argument is index/value array slice, use array slice
1626
1627(F) You used index/value array slice syntax (C<%array[...]>) as
1628the argument to C<delete>. You probably meant C<@array[...]> with
1629an @ symbol instead.
1630
1631=item delete argument is key/value hash slice, use hash slice
1632
1633(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1634C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1635
0ffcbc25
FC
1636=item delete argument is not a HASH or ARRAY element or slice
1637
4a0af295 1638(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1639such as:
1640
1641 $foo{$bar}
1642 $ref->{"susie"}[12]
1643
1644or a hash or array slice, such as:
1645
1646 @foo[$bar, $baz, $xyzzy]
1647 @{$ref->[12]}{"susie", "queue"}
1648
fc36a67e
PP
1649=item Delimiter for here document is too long
1650
be771a83
GS
1651(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1652long for Perl to handle. You have to be seriously twisted to write code
1653that triggers this error.
fc36a67e 1654
6d3b25aa
RGS
1655=item Deprecated use of my() in false conditional
1656
fa816bf3
FC
1657(D deprecated) You used a declaration similar to C<my $x if 0>. There
1658has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1659not to be cleared at scope exit when its declaration includes a false
6903afa2 1660conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1661static variable. Since we intend to fix this bug, we don't want people
6903afa2 1662relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1663declaring the variable in a separate block outside the function, eg
36fb85f3 1664
6d3b25aa
RGS
1665 sub f { my $x if 0; return $x++ }
1666
1667becomes
1668
1669 { my $x; sub f { return $x++ } }
1670
ea9d9ebc 1671Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1672lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1673
1674 sub f { state $x; return $x++ }
1675
500ab966
RGS
1676=item DESTROY created new reference to dead object '%s'
1677
1678(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1679just being DESTROYed. Perl is confused, and prefers to abort rather
1680than to create a dangling reference.
500ab966 1681
3cdd684c
TP
1682=item Did not produce a valid header
1683
1684See Server error.
1685
6df41af2
GS
1686=item %s did not return a true value
1687
1688(F) A required (or used) file must return a true value to indicate that
1689it compiled correctly and ran its initialization code correctly. It's
1690traditional to end such a file with a "1;", though any true value would
1691do. See L<perlfunc/require>.
1692
cc507455 1693=item (Did you mean &%s instead?)
4633a7c4 1694
413ff9f6
FC
1695(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1696some such.
4633a7c4 1697
cc507455 1698=item (Did you mean "local" instead of "our"?)
33633739 1699
be771a83
GS
1700(W misc) Remember that "our" does not localize the declared global
1701variable. You have declared it again in the same lexical scope, which
1702seems superfluous.
33633739 1703
cc507455 1704=item (Did you mean $ or @ instead of %?)
a0d0e21e 1705
be771a83
GS
1706(W) You probably said %hash{$key} when you meant $hash{$key} or
1707@hash{@keys}. On the other hand, maybe you just meant %hash and got
1708carried away.
748a9306 1709
7e1af8bc 1710=item Died
5f05dabc
PP
1711
1712(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1713you called it with no args and C<$@> was empty.
5f05dabc 1714
3cdd684c
TP
1715=item Document contains no data
1716
1717See Server error.
1718
62658f4d
PM
1719=item %s does not define %s::VERSION--version check failed
1720
1721(F) You said something like "use Module 42" but the Module did not
943fc58e 1722define a C<$VERSION>.
62658f4d 1723
49704364
LW
1724=item '/' does not take a repeat count
1725
1726(F) You cannot put a repeat count of any kind right after the '/' code.
1727See L<perlfunc/pack>.
1728
95cb0d72
FC
1729=item Don't know how to get file name
1730
1731(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1732somehow called on another platform. This should not happen.
1733
4021c788 1734=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1735
1736(P) The internal handling of magical variables has been cursed.
1737
1738=item do_study: out of memory
1739
1740(P) This should have been caught by safemalloc() instead.
1741
6df41af2
GS
1742=item (Do you need to predeclare %s?)
1743
56da5a46
RGS
1744(S syntax) This is an educated guess made in conjunction with the message
1745"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1746name is being referenced that hasn't been declared yet. This may be
1747because of ordering problems in your file, or because of a missing
be771a83
GS
1748"sub", "package", "require", or "use" statement. If you're referencing
1749something that isn't defined yet, you don't actually have to define the
1750subroutine or package before the current location. You can use an empty
1751"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1752
ac206dc8
RGS
1753=item dump() better written as CORE::dump()
1754
1755(W misc) You used the obsolescent C<dump()> built-in function, without fully
1756qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1757
84d78eb7
YO
1758=item dump is not supported
1759
1760(F) Your machine doesn't support dump/undump.
1761
a0d0e21e
LW
1762=item Duplicate free() ignored
1763
be771a83
GS
1764(S malloc) An internal routine called free() on something that had
1765already been freed.
a0d0e21e 1766
1109a392
MHM
1767=item Duplicate modifier '%c' after '%c' in %s
1768
35f0cd76
FC
1769(W unpack) You have applied the same modifier more than once after a
1770type in a pack template. See L<perlfunc/pack>.
1109a392 1771
0953b66b
FC
1772=item each on reference is experimental
1773
0773cb3e
FC
1774(S experimental::autoderef) C<each> with a scalar argument is experimental
1775and may change or be removed in a future Perl version. If you want to
1776take the risk of using this feature, simply disable this warning:
0953b66b 1777
d401967c 1778 no warnings "experimental::autoderef";
0953b66b 1779
4633a7c4
LW
1780=item elseif should be elsif
1781
fa816bf3
FC
1782(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1783it's ugly. Your code will be interpreted as an attempt to call a method
1784named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1785unlikely to be what you want.
1786
e0e4a6e3 1787=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1788
af6f566e 1789(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1790described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1791a regular expression without specifying the property name.
ab13f0c7 1792
85ab1d1d 1793=item entering effective %s failed
5ff3f7a4 1794
85ab1d1d 1795(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1796effective uids or gids failed.
1797
c038024b
RGS
1798=item %ENV is aliased to %s
1799
1800(F) You're running under taint mode, and the C<%ENV> variable has been
1801aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1802program's environment. This is potentially insecure.
c038024b 1803
748a9306
LW
1804=item Error converting file specification %s
1805
5f05dabc 1806(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1807specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1808single form when it must operate on them directly. Either you've passed
1809an invalid file specification to Perl, or you've found a case the
1810conversion routines don't handle. Drat.
748a9306 1811
ad19ef22 1812=item Eval-group in insecure regular expression
e4d48cc9 1813
be771a83
GS
1814(F) Perl detected tainted data when trying to compile a regular
1815expression that contains the C<(?{ ... })> zero-width assertion, which
1816is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1817
ad19ef22 1818=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1819
be771a83
GS
1820(F) Perl tried to compile a regular expression containing the
1821C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1822pattern contains interpolated values. Since that is a security risk,
1823it is not allowed. If you insist, you may still do this by using the
1824C<re 'eval'> pragma or by explicitly building the pattern from an
1825interpolated string at run time and using that in an eval(). See
1826L<perlre/(?{ code })>.
e4d48cc9 1827
ad19ef22 1828=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1829
be771a83
GS
1830(F) A regular expression contained the C<(?{ ... })> zero-width
1831assertion, but that construct is only allowed when the C<use re 'eval'>
1832pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1833
e0e4a6e3
FC
1834=item EVAL without pos change exceeded limit in regex; marked by
1835S<<-- HERE> in m/%s/
1a147d38
YO
1836
1837(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1838any text. Restructure the pattern so that text is consumed.
1a147d38 1839
9e3ec65c 1840The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1841discovered.
1842
fc36a67e
PP
1843=item Excessively long <> operator
1844
1845(F) The contents of a <> operator may not exceed the maximum size of a
1846Perl identifier. If you're just trying to glob a long list of
1847filenames, try using the glob() operator, or put the filenames into a
1848variable and glob that.
1849
ed9aa3b7
SG
1850=item exec? I'm not *that* kind of operating system
1851
af8bb25a 1852(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1853OS. See L<perlport>.
ed9aa3b7 1854
fe13d51d 1855=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1856
1857(F) The final summary message when a Perl compilation fails.
1858
0ffcbc25
FC
1859=item exists argument is not a HASH or ARRAY element or a subroutine
1860
4a0af295 1861(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1862subroutine with an ampersand, such as:
1863
1864 $foo{$bar}
1865 $ref->{"susie"}[12]
1866 &do_something
1867
1868=item exists argument is not a subroutine name
1869
ccfc2567
FC
1870(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1871and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1872
a0d0e21e
LW
1873=item Exiting eval via %s
1874
be771a83
GS
1875(W exiting) You are exiting an eval by unconventional means, such as a
1876goto, or a loop control statement.
e476b1b5
GS
1877
1878=item Exiting format via %s
1879
9a2ff54b 1880(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1881goto, or a loop control statement.
a0d0e21e 1882
0a753a76
PP
1883=item Exiting pseudo-block via %s
1884
be771a83
GS
1885(W exiting) You are exiting a rather special block construct (like a
1886sort block or subroutine) by unconventional means, such as a goto, or a
1887loop control statement. See L<perlfunc/sort>.
0a753a76 1888
a0d0e21e
LW
1889=item Exiting subroutine via %s
1890
be771a83
GS
1891(W exiting) You are exiting a subroutine by unconventional means, such
1892as a goto, or a loop control statement.
a0d0e21e
LW
1893
1894=item Exiting substitution via %s
1895
be771a83
GS
1896(W exiting) You are exiting a substitution by unconventional means, such
1897as a return, a goto, or a loop control statement.
a0d0e21e 1898
e0e4a6e3 1899=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1900
675fa9ff 1901(F) You wrote something like
c608e803
KW
1902
1903 (?13
1904
1905to denote a capturing group of the form
1906L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1907but omitted the C<")">.
1908
e0e4a6e3 1909=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1910
8b6fbf55
FC
1911(F) The C<(?[...])> extended character class regular expression construct
1912only allows character classes (including character class escapes like
1913C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1914containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1915This allows a regular expression containing just C<(?[...])> to be
1916interpolated. If you see this error message, then you probably
1917have some other C<(?...)> construct inside your character class. See
1918L<perlrecharclass/Extended Bracketed Character Classes>.
1919
30d9c59b
Z
1920=item Experimental subroutine signatures not enabled
1921
1922(F) To use subroutine signatures, you must first enable them:
1923
caa35032 1924 no warnings "experimental::signatures";
30d9c59b
Z
1925 use feature "signatures";
1926 sub foo ($left, $right) { ... }
1927
6da34ecb
FC
1928=item Experimental "%s" subs not enabled
1929
1930(F) To use lexical subs, you must first enable them:
1931
1932 no warnings 'experimental::lexical_subs';
1933 use feature 'lexical_subs';
1934 my sub foo { ... }
1935
7b8d334a
GS
1936=item Explicit blessing to '' (assuming package main)
1937
be771a83
GS
1938(W misc) You are blessing a reference to a zero length string. This has
1939the effect of blessing the reference into the package main. This is
1940usually not what you want. Consider providing a default target package,
1941e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1942
6df41af2
GS
1943=item %s: Expression syntax
1944
be771a83
GS
1945(A) You've accidentally run your script through B<csh> instead of Perl.
1946Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1947
1948=item %s failed--call queue aborted
1949
3c10abe3
AG
1950(F) An untrapped exception was raised while executing a UNITCHECK,
1951CHECK, INIT, or END subroutine. Processing of the remainder of the
1952queue of such routines has been prematurely ended.
6df41af2 1953
e0e4a6e3 1954=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1955
98d31c73 1956(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1957character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1958in your false range is interpreted as a literal "-". In a C<(?[...])>
1959construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1960the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1961the problem was discovered. See L<perlre>.
73b437c8 1962
1b1ee2ef 1963=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1964
be771a83
GS
1965(P) An error peculiar to VMS. Something untoward happened in a VMS
1966system service or RTL routine; Perl's exit status should provide more
1967details. The filename in "at %s" and the line number in "line %d" tell
1968you which section of the Perl source code is distressed.
a0d0e21e
LW
1969
1970=item fcntl is not implemented
1971
1972(F) Your machine apparently doesn't implement fcntl(). What is this, a
1973PDP-11 or something?
1974
22846ab4
AB
1975=item FETCHSIZE returned a negative value
1976
1977(F) A tied array claimed to have a negative number of elements, which
1978is not possible.
1979
f337b084
TH
1980=item Field too wide in 'u' format in pack
1981
d8b5cc61 1982(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1983which can't encode values above 63. So there is no point in asking for
1984a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1985C<u63> as the format.
f337b084 1986
af8c498a 1987=item Filehandle %s opened only for input
a0d0e21e 1988
6c8d78fb
HS
1989(W io) You tried to write on a read-only filehandle. If you intended
1990it to be a read-write filehandle, you needed to open it with "+<" or
1991"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1992write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1993
af8c498a 1994=item Filehandle %s opened only for output
a0d0e21e 1995
6c8d78fb
HS
1996(W io) You tried to read from a filehandle opened only for writing, If
1997you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1998with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1999read from the file, use "<". See L<perlfunc/open>. Another possibility
2000is that you attempted to open filedescriptor 0 (also known as STDIN) for
2001output (maybe you closed STDIN earlier?).
97828cef
RGS
2002
2003=item Filehandle %s reopened as %s only for input
2004
2005(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2006as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2007previously.
2008
2009=item Filehandle STDIN reopened as %s only for output
2010
2011(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2012as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2013
2014=item Final $ should be \$ or $name
2015
2016(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2017a literal dollar sign, or was meant to introduce a variable name that
2018happens to be missing. So you have to put either the backslash or the
2019name.
a0d0e21e 2020
56e90b21
GS
2021=item flock() on closed filehandle %s
2022
be771a83 2023(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2024some time before now. Check your control flow. flock() operates on
be771a83
GS
2025filehandles. Are you attempting to call flock() on a dirhandle by the
2026same name?
56e90b21 2027
6df41af2
GS
2028=item Format not terminated
2029
2030(F) A format must be terminated by a line with a solitary dot. Perl got
2031to the end of your file without finding such a line.
2032
a0d0e21e
LW
2033=item Format %s redefined
2034
e476b1b5 2035(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2036
2037 {
271595cc 2038 no warnings 'redefine';
a0d0e21e
LW
2039 eval "format NAME =...";
2040 }
2041
a0d0e21e
LW
2042=item Found = in conditional, should be ==
2043
e476b1b5 2044(W syntax) You said
a0d0e21e
LW
2045
2046 if ($foo = 123)
2047
2048when you meant
2049
2050 if ($foo == 123)
2051
2052(or something like that).
2053
6df41af2
GS
2054=item %s found where operator expected
2055
56da5a46
RGS
2056(S syntax) The Perl lexer knows whether to expect a term or an operator.
2057If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2058operator, it gives you this warning. Usually it indicates that an
2059operator or delimiter was omitted, such as a semicolon.
6df41af2 2060
a0d0e21e
LW
2061=item gdbm store returned %d, errno %d, key "%s"
2062
2063(S) A warning from the GDBM_File extension that a store failed.
2064
2065=item gethostent not implemented
2066
2067(F) Your C library apparently doesn't implement gethostent(), probably
2068because if it did, it'd feel morally obligated to return every hostname
2069on the Internet.
2070
69282e91 2071=item get%sname() on closed socket %s
a0d0e21e 2072
be771a83
GS
2073(W closed) You tried to get a socket or peer socket name on a closed
2074socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2075
748a9306
LW
2076=item getpwnam returned invalid UIC %#o for user "%s"
2077
2078(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2079C<getpwnam> operator returned an invalid UIC.
2080
6df41af2
GS
2081=item getsockopt() on closed socket %s
2082
be771a83
GS
2083(W closed) You tried to get a socket option on a closed socket. Did you
2084forget to check the return value of your socket() call? See
6df41af2
GS
2085L<perlfunc/getsockopt>.
2086
0f539b13
BF
2087=item given is experimental
2088
675fa9ff
FC
2089(S experimental::smartmatch) C<given> depends on smartmatch, which
2090is experimental, so its behavior may change or even be removed
2091in any future release of perl. See the explanation under
2092L<perlsyn/Experimental Details on given and when>.
0f539b13 2093
6df41af2
GS
2094=item Global symbol "%s" requires explicit package name
2095
a4edf47d 2096(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2097that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2098declared beforehand using "our", or explicitly qualified to say
2099which package the global variable is in (using "::").
6df41af2 2100
e476b1b5
GS
2101=item glob failed (%s)
2102
5ead438e 2103(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2104for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2105pattern that caused the external program to fail and exit with a
be771a83 2106nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2107resulted in a coredump, this may also mean that your csh (C shell)
2108is broken. If so, you should change all of the csh-related variables
2109in config.sh: If you have tcsh, make the variables refer to it as
2110if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2111all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2112think csh is missing. In either case, after editing config.sh, run
75b44862 2113C<./Configure -S> and rebuild Perl.
e476b1b5 2114
a0d0e21e
LW
2115=item Glob not terminated
2116
2117(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2118a term, so it's looking for the corresponding right angle bracket, and
2119not finding it. Chances are you left some needed parentheses out
2120earlier in the line, and you really meant a "less than".
a0d0e21e 2121
b35b96b6
JH
2122=item gmtime(%f) failed
2123
2124(W overflow) You called C<gmtime> with a number that it could not handle:
2125too large, too small, or NaN. The returned value is C<undef>.
2126
bcd05b94 2127=item gmtime(%f) too large
8b56d6ff 2128
e9200be3 2129(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2130it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2131date. This warning is also triggered with NaN (the special
fc003d4b
MS
2132not-a-number value).
2133
bcd05b94 2134=item gmtime(%f) too small
fc003d4b 2135
e9200be3 2136(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2137it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2138
6df41af2 2139=item Got an error from DosAllocMem
a0d0e21e 2140
6df41af2
GS
2141(P) An error peculiar to OS/2. Most probably you're using an obsolete
2142version of Perl, and this should not happen anyway.
a0d0e21e
LW
2143
2144=item goto must have label
2145
2146(F) Unlike with "next" or "last", you're not allowed to goto an
2147unspecified destination. See L<perlfunc/goto>.
2148
6651ba0b
FC
2149=item Goto undefined subroutine%s
2150
2151(F) You tried to call a subroutine with C<goto &sub> syntax, but
2152the indicated subroutine hasn't been defined, or if it was, it
2153has since been undefined.
2154
6fbc9859 2155=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2156S<<-- HERE> in m/%s/
1f4f6bf1
YO
2157
2158(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2159they must start with a non-digit word character. A common cause of
2160this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2161
5a25739d
FC
2162=item ()-group starts with a count
2163
2164(F) A ()-group started with a count. A count is supposed to follow
2165something: a template character or a ()-group. See L<perlfunc/pack>.
2166
fe13d51d 2167=item %s had compilation errors.
6df41af2
GS
2168
2169(F) The final summary message when a C<perl -c> fails.
2170
a0d0e21e
LW
2171=item Had to create %s unexpectedly
2172
be771a83
GS
2173(S internal) A routine asked for a symbol from a symbol table that ought
2174to have existed already, but for some reason it didn't, and had to be
2175created on an emergency basis to prevent a core dump.
a0d0e21e 2176
6df41af2
GS
2177=item %s has too many errors
2178
2179(F) The parser has given up trying to parse the program after 10 errors.
2180Further error messages would likely be uninformative.
2181
252aa082
JH
2182=item Hexadecimal number > 0xffffffff non-portable
2183
e476b1b5 2184(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2185(4294967295) and therefore non-portable between systems. See
2186L<perlport> for more on portability concerns.
252aa082 2187
8903cb82
PP
2188=item Identifier too long
2189
2190(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2191about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2192names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2193of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2194
e0e4a6e3
FC
2195=item Ignoring zero length \N{} in character class in regex; marked by
2196S<<-- HERE> in m/%s/
fc8cd66c 2197
b5e3739b
FC
2198(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2199zero-length sequence. When such an escape is used in a character class
2200its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2201been used, and the correct charname handler is in scope.
2202
6df41af2 2203=item Illegal binary digit %s
f675dbe5 2204
6df41af2 2205(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2206
6df41af2 2207=item Illegal binary digit %s ignored
a0d0e21e 2208
be771a83
GS
2209(W digit) You may have tried to use a digit other than 0 or 1 in a
2210binary number. Interpretation of the binary number stopped before the
2211offending digit.
a0d0e21e 2212
6597eb22
FC
2213=item Illegal character after '_' in prototype for %s : %s
2214
e4d150f1
FC
2215(W illegalproto) An illegal character was found in a prototype
2216declaration. The '_' in a prototype must be followed by a ';',
2217indicating the rest of the parameters are optional, or one of '@'
2218or '%', since those two will accept 0 or more final parameters.
6597eb22 2219
78d0fecf 2220=item Illegal character \%o (carriage return)
4fdae800 2221
d5898338 2222(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2223would any other whitespace, which means you should never see this error
2224when Perl was built using standard options. For some reason, your
2225version of Perl appears to have been built without this support. Talk
2226to your Perl administrator.
4fdae800 2227
d37a9538
ST
2228=item Illegal character in prototype for %s : %s
2229
197afce1 2230(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2231Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2232Perhaps you were trying to write a subroutine signature but didn't enable
2233that feature first (C<use feature 'signatures'>), so your signature was
2234instead interpreted as a bad prototype.
d37a9538 2235
904d85c5
RGS
2236=item Illegal declaration of anonymous subroutine
2237
2238(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2239you must always specify a block of code. See L<perlsub>.
904d85c5 2240
8e742a20
MHM
2241=item Illegal declaration of subroutine %s
2242
6903afa2 2243(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2244
a0d0e21e
LW
2245=item Illegal division by zero
2246
be771a83
GS
2247(F) You tried to divide a number by 0. Either something was wrong in
2248your logic, or you need to put a conditional in to guard against
2249meaningless input.
a0d0e21e 2250
6df41af2
GS
2251=item Illegal hexadecimal digit %s ignored
2252
be771a83
GS
2253(W digit) You may have tried to use a character other than 0 - 9 or
2254A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2255number stopped before the illegal character.
6df41af2 2256
a0d0e21e
LW
2257=item Illegal modulus zero
2258
be771a83
GS
2259(F) You tried to divide a number by 0 to get the remainder. Most
2260numbers don't take to this kindly.
a0d0e21e 2261
6df41af2 2262=item Illegal number of bits in vec
399388f4 2263
6df41af2
GS
2264(F) The number of bits in vec() (the third argument) must be a power of
2265two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2266
2267=item Illegal octal digit %s
a0d0e21e 2268
d1be9408 2269(F) You used an 8 or 9 in an octal number.
a0d0e21e 2270
399388f4 2271=item Illegal octal digit %s ignored
748a9306 2272
d1be9408 2273(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2274Interpretation of the octal number stopped before the 8 or 9.
748a9306 2275
e0e4a6e3 2276=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2277
675fa9ff 2278(F) You wrote something like
c608e803
KW
2279
2280 (?+foo)
2281
2282The C<"+"> is valid only when followed by digits, indicating a
2283capturing group. See
2284L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2285
375ed12a
JH
2286=item Illegal suidscript
2287
2288(F) The script run under suidperl was somehow illegal.
2289
fe13d51d 2290=item Illegal switch in PERL5OPT: -%c
6ff81951 2291
6df41af2 2292(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2293following switches: B<-[CDIMUdmtw]>.
6ff81951 2294
6df41af2 2295=item Ill-formed CRTL environ value "%s"
81e118e0 2296
75b44862 2297(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2298internal environ array, and encountered an element without the C<=>
2299delimiter used to separate keys from values. The element is ignored.
09bef843 2300
6df41af2 2301=item Ill-formed message in prime_env_iter: |%s|
54310121 2302
be771a83
GS
2303(W internal) A warning peculiar to VMS. Perl tried to read a logical
2304name or CLI symbol definition when preparing to iterate over %ENV, and
2305didn't see the expected delimiter between key and value, so the line was
2306ignored.
54310121 2307
6df41af2 2308=item (in cleanup) %s
9607fc9c 2309
be771a83
GS
2310(W misc) This prefix usually indicates that a DESTROY() method raised
2311the indicated exception. Since destructors are usually called by the
2312system at arbitrary points during execution, and often a vast number of
2313times, the warning is issued only once for any number of failures that
2314would otherwise result in the same message being repeated.
6df41af2 2315
be771a83
GS
2316Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2317also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2318
e0e4a6e3
FC
2319=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2320in m/%s/
0d0b4b3b 2321
675fa9ff 2322(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2323expression inside the construct was completely empty, or if there are
2324too many or few operands for the number of operators. Perl is not smart
2325enough to give you a more precise indication as to what is wrong.
2326
6fbc9859
MH
2327=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2328parent '%s'
2c7d6b9c
RGS
2329
2330(F) The method resolution order (MRO) of the given class is not
2331C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2332documentation in L<mro> for more information.
2333
979699d9
JH
2334=item In EBCDIC the v-string components cannot exceed 2147483647
2335
2336(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2337Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2338encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2339
6a2ed79a 2340=item Infinite recursion in regex
1a147d38
YO
2341
2342(F) You used a pattern that references itself without consuming any input
6903afa2 2343text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2344either consume text or fail.
2345
6dbe9451
NC
2346=item Initialization of state variables in list context currently forbidden
2347
6903afa2
FC
2348(F) Currently the implementation of "state" only permits the
2349initialization of scalar variables in scalar context. Re-write
2350C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2351context. Constructions such as C<state (@a) = foo()> will be
2352supported in a future perl release.
6dbe9451 2353
2186f873
FC
2354=item %%s[%s] in scalar context better written as $%s[%s]
2355
2356(W syntax) In scalar context, you've used an array index/value slice
2357(indicated by %) to select a single element of an array. Generally
2358it's better to ask for a scalar value (indicated by $). The difference
2359is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2360returns and when evaluating its argument, while C<%foo[&bar]> provides
2361a list context to its subscript, which can do weird things if you're
2362expecting only one subscript. When called in list context, it also
2363returns the index (what C<&bar> returns) in addition to the value.
2364
2365=item %%s{%s} in scalar context better written as $%s{%s}
2366
2367(W syntax) In scalar context, you've used a hash key/value slice
2368(indicated by %) to select a single element of a hash. Generally it's
2369better to ask for a scalar value (indicated by $). The difference
2370is that C<$foo{&bar}> always behaves like a scalar, both in the value
2371it returns and when evaluating its argument, while C<@foo{&bar}> and
2372provides a list context to its subscript, which can do weird things
2373if you're expecting only one subscript. When called in list context,
2374it also returns the key in addition to the value.
2375
a0d0e21e
LW
2376=item Insecure dependency in %s
2377
8b1a09fc 2378(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2379The tainting mechanism is turned on when you're running setuid or
2380setgid, or when you specify B<-T> to turn it on explicitly. The
2381tainting mechanism labels all data that's derived directly or indirectly
2382from the user, who is considered to be unworthy of your trust. If any
2383such data is used in a "dangerous" operation, you get this error. See
2384L<perlsec> for more information.
a0d0e21e
LW
2385
2386=item Insecure directory in %s
2387
be771a83
GS
2388(F) You can't use system(), exec(), or a piped open in a setuid or
2389setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2390the world. Also, the PATH must not contain any relative directory.
2391See L<perlsec>.
a0d0e21e 2392
62f468fc 2393=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2394
2395(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2396setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2397C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2398supplied (or potentially supplied) by the user. The script must set
2399the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2400
0e9be77f
DM
2401=item Insecure user-defined property %s
2402
2403(F) Perl detected tainted data when trying to compile a regular
2404expression that contains a call to a user-defined character property
2405function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2406See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2407
b9ef414d
FC
2408=item Integer overflow in format string for %s
2409
2410(F) The indexes and widths specified in the format string of C<printf()>
2411or C<sprintf()> are too large. The numbers must not overflow the size of
2412integers for your architecture.
2413
a7ae9550
GS
2414=item Integer overflow in %s number
2415
35928bc5 2416(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2417either as a literal or as an argument to hex() or oct() is too big for
2418your architecture, and has been converted to a floating point number.
2419On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2420representable without overflow is 0xFFFFFFFF, 037777777777, or
24210b11111111111111111111111111111111 respectively. Note that Perl
2422transparently promotes all numbers to a floating point representation
2423internally--subject to loss of precision errors in subsequent
2424operations.
bbce6d69 2425
fc89ca81
FC
2426=item Integer overflow in srand
2427
2428(S overflow) The number you have passed to srand is too big to fit
2429in your architecture's integer representation. The number has been
2430replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2431architectures). This means you may be getting less randomness than
2432you expect, because different random seeds above the maximum will
2433return the same sequence of random numbers.
2434
46314c13
JP
2435=item Integer overflow in version
2436
18da5252
FC
2437=item Integer overflow in version %d
2438
784d71ed
FC
2439(W overflow) Some portion of a version initialization is too large for
2440the size of integers for your architecture. This is not a warning
f084e84f 2441because there is no rational reason for a version to try and use an
784d71ed
FC
2442element larger than typically 2**32. This is usually caused by trying
2443to use some odd mathematical operation as a version, like 100/9.
46314c13 2444
e0e4a6e3 2445=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2446
2447(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2448The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2449discovered.
2450
748a9306
LW
2451=item Internal inconsistency in tracking vforks
2452
be771a83
GS
2453(S) A warning peculiar to VMS. Perl keeps track of the number of times
2454you've called C<fork> and C<exec>, to determine whether the current call
2455to C<exec> should affect the current script or a subprocess (see
2456L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2457Perl is making a guess and treating this C<exec> as a request to
2458terminate the Perl script and execute the specified command.
748a9306 2459
870978ae
FC
2460=item internal %<num>p might conflict with future printf extensions
2461
2462(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2463formatting follows a slightly different set of rules when called from
2464C or XS code. Specifically, formats consisting of digits followed
2465by "p" (e.g., "%7p") are reserved for future use. If you see this
2466message, then an XS module tried to call that routine with one such
2467reserved format.
2468
e0e4a6e3 2469=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2470
fa816bf3 2471(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2472S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2473discovered.
a0d0e21e 2474
6df41af2
GS
2475=item %s (...) interpreted as function
2476
75b44862 2477(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2478followed by parentheses turns into a function, with all the list
64977eb6 2479operators arguments found inside the parentheses. See
13a2d996 2480L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2481
f51551f7
FC
2482=item In '(?...)', the '(' and '?' must be adjacent in regex;
2483marked by S<<-- HERE> in m/%s/
2484
2485(F) The two-character sequence C<"(?"> in this context in a regular
2486expression pattern should be an indivisible token, with nothing
2487intervening between the C<"("> and the C<"?">, but you separated them
2488with whitespace.
2489
09bef843
SB
2490=item Invalid %s attribute: %s
2491
a4a4c9e2 2492(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2493by Perl or by a user-supplied handler. See L<attributes>.
2494
2495=item Invalid %s attributes: %s
2496
a4a4c9e2 2497(F) The indicated attributes for a subroutine or variable were not
be771a83 2498recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2499
e0e4a6e3
FC
2500=item Invalid character in charnames alias definition; marked by
2501S<<-- HERE> in '%s
225fb84f
KW
2502
2503(F) You tried to create a custom alias for a character name, with
2504the C<:alias> option to C<use charnames> and the specified character in
2505the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2506
c8028aa6
TC
2507=item Invalid \0 character in %s for %s: %s\0%s
2508
fa3234e3
FC
2509(W syscalls) Embedded \0 characters in pathnames or other system call
2510arguments produce a warning as of 5.20. The parts after the \0 were
2511formerly ignored by system calls.
c8028aa6 2512
e0e4a6e3 2513=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2514
2515(F) Only certain characters are valid for character names. The
2516indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2517
c635e13b
PP
2518=item Invalid conversion in %s: "%s"
2519
be771a83
GS
2520(W printf) Perl does not understand the given format conversion. See
2521L<perlfunc/sprintf>.
c635e13b 2522
e0e4a6e3
FC
2523=item Invalid escape in the specified encoding in regex; marked by
2524S<<-- HERE> in m/%s/
9e08bc66 2525
98d31c73 2526(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2527didn't correspond to a single character through the conversion
2528from the encoding specified by the encoding pragma.
98d31c73
FC
2529The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2530instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2531The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2532escape was discovered.
2533
8149aa9f
FC
2534=item Invalid hexadecimal number in \N{U+...}
2535
e0e4a6e3
FC
2536=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2537S<<-- HERE> in m/%s/
aec0ef10 2538
8149aa9f 2539(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2540number. Either it is empty, or you tried to use a character other than
25410 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2542
6651ba0b
FC
2543=item Invalid module name %s with -%c option: contains single ':'
2544
2545(F) The module argument to perl's B<-m> and B<-M> command-line options
2546cannot contain single colons in the module name, but only in the
2547arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2548B<-MFoo:Bar=baz> is not.
2549
2c7d6b9c
RGS
2550=item Invalid mro name: '%s'
2551
162a3e34
FC
2552(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2553where C<foo> is not a valid method resolution order (MRO). Currently,
2554the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2555a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2556
40e4140b
FC
2557=item Invalid negative number (%s) in chr
2558
2559(W utf8) You passed a negative number to C<chr>. Negative numbers are
2560not valid characters numbers, so it return the Unicode replacement
2561character (U+FFFD).
2562
6651ba0b
FC
2563=item invalid option -D%c, use -D'' to see choices
2564
8ff21bfe
FC
2565(S debugging) Perl was called with invalid debugger flags. Call perl
2566with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2567See also L<perlrun/-Dletters>.
6651ba0b 2568
e0e4a6e3 2569=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2570
2571(F) The range specified in a character class had a minimum character
7253e4e3
RK
2572greater than the maximum character. One possibility is that you forgot the
2573C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2574up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2575problem was discovered. See L<perlre>.
6df41af2 2576
d1573ac7 2577=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2578
2579(F) The range specified in the tr/// or y/// operator had a minimum
2580character greater than the maximum character. See L<perlop>.
2581
09bef843
SB
2582=item Invalid separator character %s in attribute list
2583
0120eecf 2584(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2585elements of an attribute list. If the previous attribute had a
2586parenthesised parameter list, perhaps that list was terminated too soon.
2587See L<attributes>.
09bef843 2588
b4581f09
JH
2589=item Invalid separator character %s in PerlIO layer specification %s
2590
2bfc5f71
FC
2591(W layer) When pushing layers onto the Perl I/O system, something other
2592than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2593If the previous attribute had a parenthesised parameter list, perhaps that
2594list was terminated too soon.
2595
2c86d456
DG
2596=item Invalid strict version format (%s)
2597
fa816bf3 2598(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2599A "strict" version number is a positive decimal number (integer or
2600decimal-fraction) without exponentiation or else a dotted-decimal
2601v-string with a leading 'v' character and at least three components.
a6485a24 2602The parenthesized text indicates which criteria were not met.
2c86d456
DG
2603See the L<version> module for more details on allowed version formats.
2604
49704364 2605=item Invalid type '%s' in %s
96e4d5b1 2606
49704364
LW
2607(F) The given character is not a valid pack or unpack type.
2608See L<perlfunc/pack>.
6728c851 2609
49704364 2610(W) The given character is not a valid pack or unpack type but used to be
75b44862 2611silently ignored.
96e4d5b1 2612
2c86d456
DG
2613=item Invalid version format (%s)
2614
fa816bf3 2615(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2616A "lax" version number is a positive decimal number (integer or
2617decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2618v-string. If the v-string has fewer than three components, it
2619must have a leading 'v' character. Otherwise, the leading 'v' is
2620optional. Both decimal and dotted-decimal versions may have a
2621trailing "alpha" component separated by an underscore character
2622after a fractional or dotted-decimal component. The parenthesized
2623text indicates which criteria were not met. See the L<version> module
2624for more details on allowed version formats.
46314c13 2625
798ae1b7
DG
2626=item Invalid version object
2627
fa816bf3
FC
2628(F) The internal structure of the version object was invalid.
2629Perhaps the internals were modified directly in some way or
2630an arbitrary reference was blessed into the "version" class.
798ae1b7 2631
cd209d9d 2632=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2633marked by S<<-- HERE> in m/%s/
675fa9ff 2634
cd209d9d 2635(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2636this context in a regular expression pattern should be an
2637indivisible token, with nothing intervening between the C<"(">
cd209d9d 2638and the C<"*">, but you separated them.
675fa9ff 2639
a0d0e21e
LW
2640=item ioctl is not implemented
2641
2642(F) Your machine apparently doesn't implement ioctl(), which is pretty
2643strange for a machine that supports C.
2644
c289d2f7
JH
2645=item ioctl() on unopened %s
2646
2647(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2648Check your control flow and number of arguments.
c289d2f7 2649
fe13d51d 2650=item IO layers (like '%s') unavailable
363c40c4
SB
2651
2652(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2653you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2654with 'useperlio'.
2655
80cbd5ad
JH
2656=item IO::Socket::atmark not implemented on this architecture
2657
2658(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2659neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2660
4f650b80 2661=item $* is no longer supported
b4581f09 2662
4f650b80 2663(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2664perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2665previous versions of perl the use of C<$*> enabled or disabled multi-line
2666matching within a string.
4fd19576
B
2667
2668Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2669modifiers. You can enable C</m> for a lexical scope (even a whole file)
2670with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2671then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2672
8ae1fe26
RGS
2673=item $# is no longer supported
2674
a58ac25e 2675(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2676perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2677should use the printf/sprintf functions instead.
8ae1fe26 2678
ccf3535a 2679=item '%s' is not a code reference
6ad11d81 2680
6903afa2
FC
2681(W overload) The second (fourth, sixth, ...) argument of
2682overload::constant needs to be a code reference. Either
2683an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2684
ccf3535a 2685=item '%s' is not an overloadable type
6ad11d81 2686
04a80ee0
RGS
2687(W overload) You tried to overload a constant type the overload package is
2688unaware of.
6ad11d81 2689
5a25739d
FC
2690=item -i used with no filenames on the command line, reading from STDIN
2691
2692(S inplace) The C<-i> option was passed on the command line, indicating
2693that the script is intended to edit files in place, but no files were
2694given. This is usually a mistake, since editing STDIN in place doesn't
2695make sense, and can be confusing because it can make perl look like
2696it is hanging when it is really just trying to read from STDIN. You
2697should either pass a filename to edit, or remove C<-i> from the command
2698line. See L<perlrun> for more details.
2699
aec0ef10 2700=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2701
2702(P) The regular expression parser is confused.
2703
0953b66b
FC
2704=item keys on reference is experimental
2705
0773cb3e
FC
2706(S experimental::autoderef) C<keys> with a scalar argument is experimental
2707and may change or be removed in a future Perl version. If you want to
2708take the risk of using this feature, simply disable this warning:
0953b66b 2709
d401967c 2710 no warnings "experimental::autoderef";
0953b66b 2711
a0d0e21e
LW
2712=item Label not found for "last %s"
2713
be771a83
GS
2714(F) You named a loop to break out of, but you're not currently in a loop
2715of that name, not even if you count where you were called from. See
2716L<perlfunc/last>.
a0d0e21e
LW
2717
2718=item Label not found for "next %s"
2719
2720(F) You named a loop to continue, but you're not currently in a loop of
2721that name, not even if you count where you were called from. See
2722L<perlfunc/last>.
2723
2724=item Label not found for "redo %s"
2725
2726(F) You named a loop to restart, but you're not currently in a loop of
2727that name, not even if you count where you were called from. See
2728L<perlfunc/last>.
2729
85ab1d1d 2730=item leaving effective %s failed
5ff3f7a4 2731
85ab1d1d 2732(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2733effective uids or gids failed.
2734
49704364
LW
2735=item length/code after end of string in unpack
2736
d7f8936a 2737(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2738length/code combination tried to obtain more data. This results in
2739an undefined value for the length. See L<perlfunc/pack>.
49704364 2740
25e26107 2741=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2742
0d46a4e7
FC
2743(W syntax) You used length() on either an array or a hash when you
2744probably wanted a count of the items.
e508c8a4
MH
2745
2746Array size can be obtained by doing:
2747
2748 scalar(@array);
2749
2750The number of items in a hash can be obtained by doing:
2751
2752 scalar(keys %hash);
2753
f0e67a1d
Z
2754=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2755
d4fe7078
RS
2756(F) An extension is attempting to insert text into the current parse
2757(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2758couldn't be part of the current input. This is an inherent pitfall
2759of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2760it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2761
2762=item Lexing code internal error (%s)
2763
2764(F) Lexing code supplied by an extension violated the lexer's API in a
2765detectable way.
2766
69282e91 2767=item listen() on closed socket %s
a0d0e21e 2768
be771a83
GS
2769(W closed) You tried to do a listen on a closed socket. Did you forget
2770to check the return value of your socket() call? See
2771L<perlfunc/listen>.
a0d0e21e 2772
6651ba0b
FC
2773=item List form of piped open not implemented
2774
2775(F) On some platforms, notably Windows, the three-or-more-arguments
2776form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2777Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2778
b35b96b6
JH
2779=item localtime(%f) failed
2780
2781(W overflow) You called C<localtime> with a number that it could not handle:
2782too large, too small, or NaN. The returned value is C<undef>.
2783
bcd05b94 2784=item localtime(%f) too large
8b56d6ff 2785
e9200be3 2786(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2787than it can reliably handle and C<localtime> probably returned the
6903afa2 2788wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2789not-a-number value).
2790
bcd05b94 2791=item localtime(%f) too small
fc003d4b 2792
e9200be3 2793(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2794than it can reliably handle and C<localtime> probably returned the
e7a1a147 2795wrong date.
8b56d6ff 2796
58e23c8d 2797=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2798
2799(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2800handle. This restriction may be eased in a future release.
2e50fd82 2801
b88df990
NC
2802=item Lost precision when %s %f by 1
2803
e63e8a91
FC
2804(W imprecision) The value you attempted to increment or decrement by one
2805is too large for the underlying floating point representation to store
2806accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2807warning because it has already switched from integers to floating point
2808when values are too large for integers, and now even floating point is
2809insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2810
93fad930 2811=item lstat() on filehandle%s
2f7da168
RK
2812
2813(W io) You tried to do an lstat on a filehandle. What did you mean
2814by that? lstat() makes sense only on filenames. (Perl did a fstat()
2815instead on the filehandle.)
2816
345d70e3 2817=item lvalue attribute %s already-defined subroutine
bb3abb05 2818
345d70e3
FC
2819(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2820attribute on or off on a Perl subroutine that is already defined
2821does not always work properly. It may or may not do what you
2822want, depending on what code is inside the subroutine, with exact
2823details subject to change between Perl versions. Only do this
2824if you really know what you are doing.
bb3abb05 2825
885ef6f5
GG
2826=item lvalue attribute ignored after the subroutine has been defined
2827
345d70e3
FC
2828(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2829subroutine an lvalue subroutine after it has been defined is
2830not permitted. To make the subroutine an lvalue subroutine,
2831add the lvalue attribute to the definition, or put the C<sub
2832foo :lvalue;> declaration before the definition.
2833
2834See also L<attributes.pm|attributes>.
885ef6f5 2835
6f1b3ab0
FC
2836=item Magical list constants are not supported
2837
2838(F) You assigned a magical array to a stash element, and then tried
2839to use the subroutine from the same slot. You are asking Perl to do
2840something it cannot do, details subject to change between Perl versions.
2841
2db62bbc 2842=item Malformed integer in [] in pack
49704364 2843
2db62bbc 2844(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2845are permitted. See L<perlfunc/pack>.
2846
2847=item Malformed integer in [] in unpack
2848
2db62bbc 2849(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2850are permitted. See L<perlfunc/pack>.
2851
6df41af2
GS
2852=item Malformed PERLLIB_PREFIX
2853
2854(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2855
2856 prefix1;prefix2
2857
2858or
6df41af2
GS
2859 prefix1 prefix2
2860
be771a83
GS
2861with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2862a builtin library search path, prefix2 is substituted. The error may
2863appear if components are not found, or are too long. See
fecfaeb8 2864"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2865
2f758a16
ST
2866=item Malformed prototype for %s: %s
2867
d37a9538
ST
2868(F) You tried to use a function with a malformed prototype. The
2869syntax of function prototypes is given a brief compile-time check for
2870obvious errors like invalid characters. A more rigorous check is run
2871when the function is called.
30d9c59b
Z
2872Perhaps the function's author was trying to write a subroutine signature
2873but didn't enable that feature first (C<use feature 'signatures'>),
2874so the signature was instead interpreted as a bad prototype.
2f758a16 2875
ba210ebe
JH
2876=item Malformed UTF-8 character (%s)
2877
4d6f11e5 2878(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2879encoding rules, even though it had the UTF8 flag on.
ba210ebe 2880
2575c402
JW
2881One possible cause is that you set the UTF8 flag yourself for data that
2882you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28838-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2884
2885If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2886sequences are handled gracefully, but if you use C<:utf8>, the flag is
2887set without validating the data, possibly resulting in this error
2888message.
2889
2890See also L<Encode/"Handling Malformed Data">.
901b21bf 2891
107160e2
KW
2892=item Malformed UTF-8 character immediately after '%s'
2893
2894(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2895encoding rules. The message prints out the properly encoded characters
2896just before the first bad one. If C<utf8> warnings are enabled, a
2897warning is generated that gives more details about the type of
2898malformation.
2899
bde9e88d 2900=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2901
2902(F) The charnames handler returned malformed UTF-8.
2903
4a5d3a93
FC
2904=item Malformed UTF-8 string in '%c' format in unpack
2905
2906(F) You tried to unpack something that didn't comply with UTF-8 encoding
2907rules and perl was unable to guess how to make more progress.
2908
f337b084
TH
2909=item Malformed UTF-8 string in pack
2910
2911(F) You tried to pack something that didn't comply with UTF-8 encoding
2912rules and perl was unable to guess how to make more progress.
2913
2914=item Malformed UTF-8 string in unpack
2915
2916(F) You tried to unpack something that didn't comply with UTF-8 encoding
2917rules and perl was unable to guess how to make more progress.
2918
4a5d3a93 2919=item Malformed UTF-16 surrogate
f337b084 2920
4a5d3a93
FC
2921(F) Perl thought it was reading UTF-16 encoded character data but while
2922doing it Perl met a malformed Unicode surrogate.
2923
30d9c59b
Z
2924=item Mandatory parameter follows optional parameter
2925
2926(F) In a subroutine signature, you wrote something like "$a = undef,
2927$b", making an earlier parameter optional and a later one mandatory.
2928Parameters are filled from left to right, so it's impossible for the
2929caller to omit an earlier one and pass a later one. If you want to act
2930as if the parameters are filled from right to left, declare the rightmost
2931optional and then shuffle the parameters around in the subroutine's body.
2932
2d88a86a
KW
2933=item Matched non-Unicode code point 0x%X against Unicode property; may
2934not be portable
2935
2936(S non_unicode) Perl allows strings to contain a superset of
2937Unicode code points; each code point may be as large as what is storable
2938in an unsigned integer on your system, but these may not be accepted by
2939other languages/systems. This message occurs when you matched a string
2940containing such a code point against a regular expression pattern, and
2941the code point was matched against a Unicode property, C<\p{...}> or
2942C<\P{...}>. Unicode properties are only defined on Unicode code points,
2943so the result of this match is undefined by Unicode, but Perl (starting
2944in v5.20) treats non-Unicode code points as if they were typical
2945unassigned Unicode ones, and matched this one accordingly. Whether a
2946given property matches these code points or not is specified in
2947L<perluniprops/Properties accessible through \p{} and \P{}>.
2948
2949This message is suppressed (unless it has been made fatal) if it is
2950immaterial to the results of the match if the code point is Unicode or
2951not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2952the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2953Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2954every code point except these 22.)
2955
2956Getting this message indicates that the outcome of the match arguably
2957should have been the opposite of what actually happened. If you think
2958that is the case, you may wish to make the C<non_unicode> warnings
2959category fatal; if you agree with Perl's decision, you may wish to turn
2960off this category.
2961
2962See L<perlunicode/Beyond Unicode code points> for more information.
2963
e0e4a6e3
FC
2964=item %s matches null string many times in regex; marked by S<<-- HERE> in
2965m/%s/
4a5d3a93
FC
2966
2967(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2968regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2969shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2970See L<perlre>.
f337b084 2971
de42a5a9 2972=item Maximal count of pending signals (%u) exceeded
2563cec5 2973
6903afa2 2974(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2975usually indicates that your operating system tried to deliver signals
2976too fast (with a very high priority), starving the perl process from
2977resources it would need to reach a point where it can process signals
6903afa2 2978safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2979
25f58aea
PN
2980=item "%s" may clash with future reserved word
2981
2982(W) This warning may be due to running a perl5 script through a perl4
2983interpreter, especially if the word that is being warned about is
2984"use" or "my".
2985
0d2487cd 2986=item '%' may not be used in pack
6df41af2
GS
2987
2988(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2989checksumming process loses information, and you can't go the other way.
2990See L<perlfunc/unpack>.
6df41af2 2991
a0d0e21e
LW
2992=item Method for operation %s not found in package %s during blessing
2993
2994(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2995doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2996
3cdd684c
TP
2997=item Method %s not permitted
2998
2999See Server error.
3000
a0d0e21e
LW
3001=item Might be a runaway multi-line %s string starting on line %d
3002
3003(S) An advisory indicating that the previous error may have been caused
3004by a missing delimiter on a string or pattern, because it eventually
3005ended earlier on the current line.
3006
3007=item Misplaced _ in number
3008
d4ced10d
JH
3009(W syntax) An underscore (underbar) in a numeric constant did not
3010separate two digits.
a0d0e21e 3011
7baa4690
HS
3012=item Missing argument in %s
3013
3664866e
AB
3014(W missing) You called a function with fewer arguments than other
3015arguments you supplied indicated would be needed.
3016
3017Currently only emitted when a printf-type format required more
3018arguments than were supplied, but might be used in the future for
3019other cases where we can statically determine that arguments to
3020functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3021
9e81e6a1
RGS
3022=item Missing argument to -%c
3023
3024(F) The argument to the indicated command line switch must follow
3025immediately after the switch, without intervening spaces.
3026
ff3f963a 3027=item Missing braces on \N{}
423cee85 3028
e0e4a6e3 3029=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3030
4a2d328f 3031(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3032double-quotish context. This can also happen when there is a space
3033(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3034This modifier does not change the requirement that the brace immediately
3035follow the C<\N>.
423cee85 3036
f0a2b745
KW
3037=item Missing braces on \o{}
3038
3039(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3040
a0d0e21e
LW
3041=item Missing comma after first argument to %s function
3042
3043(F) While certain functions allow you to specify a filehandle or an
3044"indirect object" before the argument list, this ain't one of them.
3045
06eaf0bc
GS
3046=item Missing command in piped open
3047
be771a83
GS
3048(W pipe) You used the C<open(FH, "| command")> or
3049C<open(FH, "command |")> construction, but the command was missing or
3050blank.
06eaf0bc 3051
961ce445
RGS
3052=item Missing control char name in \c
3053
3054(F) A double-quoted string ended with "\c", without the required control
3055character name.
3056
591f5ca2
FC
3057=item Missing ']' in prototype for %s : %s
3058
bfe11873 3059(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3060
8767b1ab 3061=item Missing name in "%s sub"
6df41af2 3062
87444db5 3063(F) The syntax for lexically scoped subroutines requires that
be771a83 3064they have a name with which they can be found.
6df41af2
GS
3065
3066=item Missing $ on loop variable
3067
be771a83
GS
3068(F) Apparently you've been programming in B<csh> too much. Variables
3069are always mentioned with the $ in Perl, unlike in the shells, where it
3070can vary from one line to the next.
6df41af2 3071
cc507455 3072=item (Missing operator before %s?)
748a9306 3073
56da5a46
RGS
3074(S syntax) This is an educated guess made in conjunction with the message
3075"%s found where operator expected". Often the missing operator is a comma.
748a9306 3076
f51551f7
FC
3077=item Missing or undefined argument to require
3078
3079(F) You tried to call require with no argument or with an undefined
3080value as an argument. Require expects either a package name or a
3081file-specification as an argument. See L<perlfunc/require>.
3082
e0e4a6e3 3083=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3084
ff3f963a
KW
3085(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3086
4a68bf9d 3087=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3088
d32207c9
FC
3089(F) C<\N> has two meanings.
3090
3091The traditional one has it followed by a name enclosed in braces,
3092meaning the character (or sequence of characters) given by that
fa816bf3 3093name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3094double-quoted strings and regular expression patterns. In patterns,
3095it doesn't have the meaning an unescaped C<*> does.
3096
3097Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3098in patterns, namely to match a non-newline character. (This is short
3099for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3100
3101This can lead to some ambiguities. When C<\N> is not followed immediately
3102by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3103form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3104means to match the given quantity of non-newlines (in these examples,
31053; and 5 or more, respectively). In all other case, where there is a
3106C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3107
3108However, if there is no matching C<}>, Perl doesn't know if it was
3109mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3110If you meant the former, add the right brace; if you meant the latter,
3111escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3112
d98d5fff 3113=item Missing right curly or square bracket
a0d0e21e 3114
be771a83
GS
3115(F) The lexer counted more opening curly or square brackets than closing
3116ones. As a general rule, you'll find it's missing near the place you
3117were last editing.
a0d0e21e 3118
6df41af2
GS
3119=item (Missing semicolon on previous line?)
3120
56da5a46
RGS
3121(S syntax) This is an educated guess made in conjunction with the message
3122"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3123the previous line just because you saw this message.
3124
a0d0e21e
LW
3125=item Modification of a read-only value attempted
3126
3127(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3128constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3129catches that. But an easy way to do the same thing is:
3130
3131 sub mod { $_[0] = 1 }
3132 mod(2);
3133
3134Another way is to assign to a substr() that's off the end of the string.
3135
c5674021
PDF
3136Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3137is aliased to a constant in the look I<LIST>:
3138
b7e4ecc1
FC
3139 $x = 1;
3140 foreach my $n ($x, 2) {
3141 $n *= 2; # modifies the $x, but fails on attempt to
3142 } # modify the 2
c5674021 3143
7a4340ed 3144=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3145
3146(F) You tried to make an array value spring into existence, and the
3147subscript was probably negative, even counting from end of the array
3148backwards.
3149
7a4340ed 3150=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3151
be771a83
GS
3152(P) You tried to make a hash value spring into existence, and it
3153couldn't be created for some peculiar reason.
a0d0e21e
LW
3154
3155=item Module name must be constant
3156
3157(F) Only a bare module name is allowed as the first argument to a "use".
3158
be98fb35 3159=item Module name required with -%c option
6df41af2 3160
be98fb35
GS
3161(F) The C<-M> or C<-m> options say that Perl should load some module, but
3162you omitted the name of the module. Consult L<perlrun> for full details
3163about C<-M> and C<-m>.
6df41af2 3164
fe13d51d 3165=item More than one argument to '%s' open
ed9aa3b7 3166
6903afa2 3167(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3168can happen if you are trying to open a pipe to a command that takes a
3169list of arguments, but have forgotten to specify a piped open mode.
3170See L<perlfunc/open> for details.
3171
85396b18
FC
3172=item mprotect for COW string %p %u failed with %d
3173
3174(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3175L<perlguts/"Copy on Write">), but a shared string buffer
3176could not be made read-only.
3177
92951bce
FC
3178=item mprotect for %p %u failed with %d
3179
85396b18
FC
3180(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3181but an op tree could not be made read-only.
3182
3183=item mprotect RW for COW string %p %u failed with %d
3184
3185(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3186L<perlguts/"Copy on Write">), but a read-only shared string
3187buffer could not be made mutable.
3188
92951bce
FC
3189=item mprotect RW for %p %u failed with %d
3190
3191(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3192L<perlhacktips>), but a read-only op tree could not be made
3193mutable before freeing the ops.
92951bce 3194
a0d0e21e
LW
3195=item msg%s not implemented
3196
3197(F) You don't have System V message IPC on your system.
3198
3199=item Multidimensional syntax %s not supported
3200
75b44862
GS
3201(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3202They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3203
49704364 3204=item '/' must follow a numeric type in unpack
6df41af2 3205
49704364
LW
3206(F) You had an unpack template that contained a '/', but this did not
3207follow some unpack specification producing a numeric value.
3208See L<perlfunc/pack>.
6df41af2
GS
3209
3210=item "my sub" not yet implemented
3211
be771a83
GS
3212(F) Lexically scoped subroutines are not yet implemented. Don't try
3213that yet.
6df41af2 3214
5a25739d
FC
3215=item "my %s" used in sort comparison
3216
3217(W syntax) The package variables $a and $b are used for sort comparisons.
3218You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3219sort comparison block, and the variable had earlier been declared as a
3220lexical variable. Either qualify the sort variable with the package
3221name, or rename the lexical variable.
3222
fd1b7234 3223=item "my" variable %s can't be in a package
6df41af2 3224
be771a83
GS
3225(F) Lexically scoped variables aren't in a package, so it doesn't make
3226sense to try to declare one with a package qualifier on the front. Use
3227local() if you want to localize a package variable.
09bef843 3228
8149aa9f
FC
3229=item Name "%s::%s" used only once: possible typo
3230
c59aba6c
FC
3231(W once) Typographical errors often show up as unique variable
3232names. If you had a good reason for having a unique name, then
3233just mention it again somehow to suppress the message. The C<our>
08a33b6b 3234declaration is also provided for this purpose.
c59aba6c 3235
66a1f5ec
FC
3236NOTE: This warning detects package symbols that have been used
3237only once. This means lexical variables will never trigger this
3238warning. It also means that all of the package variables $c, @c,
3239%c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3240format) are considered the same; if a program uses $c only once
3241but also uses any of the others it will not trigger this warning.
3242Symbols beginning with an underscore and symbols using special
3243identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3244
e0e4a6e3 3245=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3246
3247(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3248exactly 3 digits long. This helps catch some ambiguities. If your
3249constant is too short, add leading zeros, like
3250
3251 (?[ [ \078 ] ]) # Syntax error!
3252 (?[ [ \0078 ] ]) # Works
3253 (?[ [ \007 8 ] ]) # Clearer
3254
3255The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3256need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3257two separate things, you need to separate them:
0d0b4b3b
KW
3258
3259 (?[ [ \7776 ] ]) # Syntax error!
3260 (?[ [ \o{7776} ] ]) # One meaning
3261 (?[ [ \777 6 ] ]) # Another meaning
3262 (?[ [ \777 \006 ] ]) # Still another
3263
49704364
LW
3264=item Negative '/' count in unpack
3265
3266(F) The length count obtained from a length/code unpack operation was
3267negative. See L<perlfunc/pack>.
3268
a0d0e21e
LW
3269=item Negative length
3270
be771a83
GS
3271(F) You tried to do a read/write/send/recv operation with a buffer
3272length that is less than 0. This is difficult to imagine.
a0d0e21e 3273
ed9aa3b7
SG
3274=item Negative offset to vec in lvalue context
3275
3276(F) When C<vec> is called in an lvalue context, the second argument must be
3277greater than or equal to zero.
3278
b3211734
KW
3279=item Negative repeat count does nothing
3280
3281(W numeric) You tried to execute the
3282L<C<x>|perlop/Multiplicative Operators> repetition operator fewer than 0
3283times, which doesn't make sense.
3284
e0e4a6e3 3285=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3286
6903afa2 3287(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3288So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3289whereabouts in the regular expression the problem was discovered.
a0d0e21e 3290
7253e4e3 3291Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3292C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3293
6df41af2 3294=item %s never introduced
a0d0e21e 3295
be771a83
GS
3296(S internal) The symbol in question was declared but somehow went out of
3297scope before it could possibly have been used.
a0d0e21e 3298
2c7d6b9c
RGS
3299=item next::method/next::can/maybe::next::method cannot find enclosing method
3300
3301(F) C<next::method> needs to be called within the context of a
3302real method in a real package, and it could not find such a context.
3303See L<mro>.
3304
5a25739d 3305=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3306marked by S<<-- HERE> in m/%s/
5a25739d 3307
32a77fbe
FC
3308(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3309bracketed character class, for the same reason that C<.> in a character
3310class loses its specialness: it matches almost everything, which is
3311probably not what you want.
5a25739d 3312
0b4ce96d 3313=item \N{} in character class restricted to one character in regex; marked
e0e4a6e3 3314by S<<-- HERE> in m/%s/
0b4ce96d
FC