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infnan: perldiag entries fixing, add "in pack" to one message.
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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
c32124fe
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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
FC
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
FC
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
4df3f177
SP
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:
34d09196
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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?
6df41af2
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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
68dc0745
PP
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
9e24b6e2
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
0c7df902
JH
549=item Cannot chr %f
550
551(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
552
5dee29d4 553=item Cannot compress %f in pack
0c7df902 554
5dee29d4
JH
555(F) You tried compressing an infinity or not-a-number as an unsigned
556integer with BER, which makes no sense.
0c7df902 557
49704364 558=item Cannot compress integer in pack
0258719b
NC
559
560(F) An argument to pack("w",...) was too large to compress. The BER
5dee29d4
JH
561compressed integer format can only be used with positive integers, and
562you attempted to a very large number (> 1e308). See L<perlfunc/pack>.
0258719b 563
49704364 564=item Cannot compress negative numbers in pack
0258719b
NC
565
566(F) An argument to pack("w",...) was negative. The BER compressed integer
567format can only be used with positive integers. See L<perlfunc/pack>.
568
5c1f4d79
NC
569=item Cannot convert a reference to %s to typeglob
570
6903afa2
FC
571(F) You manipulated Perl's symbol table directly, stored a reference
572in it, then tried to access that symbol via conventional Perl syntax.
573The access triggers Perl to autovivify that typeglob, but it there is
574no legal conversion from that type of reference to a typeglob.
5c1f4d79 575
4040665a 576=item Cannot copy to %s
ba2fdce6
NC
577
578(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 579be directly assigned to.
ba2fdce6 580
b5d97229
RGS
581=item Cannot find encoding "%s"
582
583(S io) You tried to apply an encoding that did not exist to a filehandle,
584either with open() or binmode().
585
0c7df902
JH
586=item Cannot pack %f with '%c'
587
5dee29d4 588(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
589which makes no sense.
590
591=item Cannot printf %f with '%c'
592
593(F) You tried printing an infinity or not-a-number as a character (%c),
594which makes no sense. Maybe you meant '%s', or just stringifying it?
595
7355df7e
FC
596=item Cannot set tied @DB::args
597
598(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
599is not supported. (Before this error was added, it used to crash.)
600
ce65bc73
FC
601=item Cannot tie unreifiable array
602
603(P) You somehow managed to call C<tie> on an array that does not
604keep a reference count on its arguments and cannot be made to
605do so. Such arrays are not even supposed to be accessible to
606Perl code, but are only used internally.
607
96ebfdd7
RK
608=item Can only compress unsigned integers in pack
609
610(F) An argument to pack("w",...) was not an integer. The BER compressed
611integer format can only be used with positive integers, and you attempted
612to compress something else. See L<perlfunc/pack>.
613
a0d0e21e
LW
614=item Can't bless non-reference value
615
616(F) Only hard references may be blessed. This is how Perl "enforces"
617encapsulation of objects. See L<perlobj>.
618
dc57907a
RGS
619=item Can't "break" in a loop topicalizer
620
0d863452 621(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 622a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
623
624=item Can't "break" outside a given block
dc57907a 625
0d863452
RH
626(F) You called C<break>, but you're not inside a C<given> block.
627
6df41af2
GS
628=item Can't call method "%s" on an undefined value
629
630(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
631object reference or package name contains an undefined value. Something
632like this will reproduce the error:
6df41af2
GS
633
634 $BADREF = undef;
635 process $BADREF 1,2,3;
636 $BADREF->process(1,2,3);
637
a0d0e21e
LW
638=item Can't call method "%s" on unblessed reference
639
54310121 640(F) A method call must know in what package it's supposed to run. It
be771a83
GS
641ordinarily finds this out from the object reference you supply, but you
642didn't supply an object reference in this case. A reference isn't an
643object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
644
645=item Can't call method "%s" without a package or object reference
646
647(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
648object reference or package name contains an expression that returns a
649defined value which is neither an object reference nor a package name.
72b5445b
GS
650Something like this will reproduce the error:
651
652 $BADREF = 42;
653 process $BADREF 1,2,3;
654 $BADREF->process(1,2,3);
655
dfe378f1
FC
656=item Can't call mro_isa_changed_in() on anonymous symbol table
657
658(P) Perl got confused as to whether a hash was a plain hash or a
659symbol table hash when trying to update @ISA caches.
660
2bf7e7b2
FC
661=item Can't call mro_method_changed_in() on anonymous symbol table
662
663(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
664not attached to the symbol table.
665
a0d0e21e
LW
666=item Can't chdir to %s
667
f703fc96 668(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
669that you can chdir to, possibly because it doesn't exist.
670
0545a864 671=item Can't check filesystem of script "%s" for nosuid
104d25b7 672
be771a83
GS
673(P) For some reason you can't check the filesystem of the script for
674nosuid.
104d25b7 675
22e74366 676=item Can't coerce %s to %s in %s
a0d0e21e
LW
677
678(F) Certain types of SVs, in particular real symbol table entries
55497cff 679(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
680say things like:
681
682 *foo += 1;
683
684You CAN say
685
686 $foo = *foo;
687 $foo += 1;
688
689but then $foo no longer contains a glob.
690
0d863452 691=item Can't "continue" outside a when block
dc57907a 692
0d863452
RH
693(F) You called C<continue>, but you're not inside a C<when>
694or C<default> block.
695
a0d0e21e
LW
696=item Can't create pipe mailbox
697
be771a83
GS
698(P) An error peculiar to VMS. The process is suffering from exhausted
699quotas or other plumbing problems.
a0d0e21e 700
eb64745e
GS
701=item Can't declare %s in "%s"
702
30c282f6
NC
703(F) Only scalar, array, and hash variables may be declared as "my", "our" or
704"state" variables. They must have ordinary identifiers as names.
a0d0e21e 705
fc7debfb
FC
706=item Can't "default" outside a topicalizer
707
708(F) You have used a C<default> block that is neither inside a
709C<foreach> loop nor a C<given> block. (Note that this error is
710issued on exit from the C<default> block, so you won't get the
711error if you use an explicit C<continue>.)
712
6df41af2
GS
713=item Can't do inplace edit: %s is not a regular file
714
be771a83 715(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 716a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 717
a0d0e21e
LW
718=item Can't do inplace edit on %s: %s
719
be771a83
GS
720(S inplace) The creation of the new file failed for the indicated
721reason.
a0d0e21e 722
54310121 723=item Can't do inplace edit without backup
a0d0e21e 724
be771a83
GS
725(F) You're on a system such as MS-DOS that gets confused if you try
726reading from a deleted (but still opened) file. You have to say
727C<-i.bak>, or some such.
a0d0e21e 728
10f9c03d 729=item Can't do inplace edit: %s would not be unique
a0d0e21e 730
e476b1b5 731(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
732characters and Perl was unable to create a unique filename during
733inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 734
a0d0e21e
LW
735=item Can't do waitpid with flags
736
be771a83
GS
737(F) This machine doesn't have either waitpid() or wait4(), so only
738waitpid() without flags is emulated.
a0d0e21e 739
a0d0e21e
LW
740=item Can't emulate -%s on #! line
741
be771a83
GS
742(F) The #! line specifies a switch that doesn't make sense at this
743point. For example, it'd be kind of silly to put a B<-x> on the #!
744line.
a0d0e21e 745
1109a392
MHM
746=item Can't %s %s-endian %ss on this platform
747
748(F) Your platform's byte-order is neither big-endian nor little-endian,
749or it has a very strange pointer size. Packing and unpacking big- or
750little-endian floating point values and pointers may not be possible.
751See L<perlfunc/pack>.
752
a0d0e21e
LW
753=item Can't exec "%s": %s
754
d1be9408 755(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
756named program for the indicated reason. Typical reasons include: the
757permissions were wrong on the file, the file wasn't found in
758C<$ENV{PATH}>, the executable in question was compiled for another
759architecture, or the #! line in a script points to an interpreter that
760can't be run for similar reasons. (Or maybe your system doesn't support
761#! at all.)
a0d0e21e
LW
762
763=item Can't exec %s
764
be771a83
GS
765(F) Perl was trying to execute the indicated program for you because
766that's what the #! line said. If that's not what you wanted, you may
767need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
768
769=item Can't execute %s
770
be771a83
GS
771(F) You used the B<-S> switch, but the copies of the script to execute
772found in the PATH did not have correct permissions.
2a92aaa0 773
6df41af2 774=item Can't find an opnumber for "%s"
2a92aaa0 775
be771a83
GS
776(F) A string of a form C<CORE::word> was given to prototype(), but there
777is no builtin with the name C<word>.
6df41af2 778
56ca2fc0
JH
779=item Can't find %s character property "%s"
780
781(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 782could not be found. Maybe you misspelled the name of the property?
e1b711da 783See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 784for a complete list of available official properties.
56ca2fc0 785
6df41af2
GS
786=item Can't find label %s
787
be771a83
GS
788(F) You said to goto a label that isn't mentioned anywhere that it's
789possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
790
791=item Can't find %s on PATH
792
be771a83
GS
793(F) You used the B<-S> switch, but the script to execute could not be
794found in the PATH.
a0d0e21e 795
6df41af2 796=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 797
be771a83
GS
798(F) You used the B<-S> switch, but the script to execute could not be
799found in the PATH, or at least not with the correct permissions. The
800script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
801
802=item Can't find string terminator %s anywhere before EOF
803
be771a83
GS
804(F) Perl strings can stretch over multiple lines. This message means
805that the closing delimiter was omitted. Because bracketed quotes count
806nesting levels, the following is missing its final parenthesis:
a0d0e21e 807
fb73857a
PP
808 print q(The character '(' starts a side comment.);
809
97b3d10f 810If you're getting this error from a here-document, you may have
b6b8cb97
FC
811included unseen whitespace before or after your closing tag or there
812may not be a linebreak after it. A good programmer's editor will have
813a way to help you find these characters (or lack of characters). See
814L<perlop> for the full details on here-documents.
a0d0e21e 815
660a4616
ST
816=item Can't find Unicode property definition "%s"
817
5f8ad6b6
FC
818(F) You may have tried to use C<\p> which means a Unicode
819property (for example C<\p{Lu}> matches all uppercase
fa816bf3 820letters). If you did mean to use a Unicode property, see
e1b711da 821L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 822for a complete list of available properties. If you didn't
fa816bf3
FC
823mean to use a Unicode property, escape the C<\p>, either by
824C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 825until C<\E>).
660a4616 826
b3647a36 827=item Can't fork: %s
a0d0e21e 828
be771a83
GS
829(F) A fatal error occurred while trying to fork while opening a
830pipeline.
a0d0e21e 831
b3647a36
SR
832=item Can't fork, trying again in 5 seconds
833
c973c02e 834(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
835after five seconds.
836
748a9306
LW
837=item Can't get filespec - stale stat buffer?
838
be771a83
GS
839(S) A warning peculiar to VMS. This arises because of the difference
840between access checks under VMS and under the Unix model Perl assumes.
841Under VMS, access checks are done by filename, rather than by bits in
842the stat buffer, so that ACLs and other protections can be taken into
843account. Unfortunately, Perl assumes that the stat buffer contains all
844the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 845the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
846the device name and FID present in the stat buffer, but this works only
847if you haven't made a subsequent call to the CRTL stat() routine,
848because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
849appears, the name lookup failed, and the access-checking routine gave up
850and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
851routine knows about the Perl C<stat> operator and file tests, so you
852shouldn't ever see this warning in response to a Perl command; it arises
853only if some internal code takes stat buffers lightly.)
748a9306 854
a0d0e21e
LW
855=item Can't get pipe mailbox device name
856
be771a83
GS
857(P) An error peculiar to VMS. After creating a mailbox to act as a
858pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
859
860=item Can't get SYSGEN parameter value for MAXBUF
861
748a9306
LW
862(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
863mailbox buffers to be, and didn't get an answer.
a0d0e21e 864
6df41af2 865=item Can't "goto" into the middle of a foreach loop
a0d0e21e 866
be771a83
GS
867(F) A "goto" statement was executed to jump into the middle of a foreach
868loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
869
870=item Can't "goto" out of a pseudo block
871
be771a83
GS
872(F) A "goto" statement was executed to jump out of what might look like
873a block, except that it isn't a proper block. This usually occurs if
874you tried to jump out of a sort() block or subroutine, which is a no-no.
875See L<perlfunc/goto>.
a0d0e21e 876
5a25739d
FC
877=item Can't goto subroutine from an eval-%s
878
879(F) The "goto subroutine" call can't be used to jump out of an eval
880"string" or block.
881
9850bf21 882=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 883
9850bf21
RH
884(F) The "goto subroutine" call can't be used to jump out of the
885comparison sub for a sort(), or from a similar callback (such
886as the reduce() function in List::Util).
887
6df41af2
GS
888=item Can't goto subroutine outside a subroutine
889
be771a83
GS
890(F) The deeply magical "goto subroutine" call can only replace one
891subroutine call for another. It can't manufacture one out of whole
892cloth. In general you should be calling it out of only an AUTOLOAD
893routine anyway. See L<perlfunc/goto>.
6df41af2 894
0b5b802d
GS
895=item Can't ignore signal CHLD, forcing to default
896
be771a83
GS
897(W signal) Perl has detected that it is being run with the SIGCHLD
898signal (sometimes known as SIGCLD) disabled. Since disabling this
899signal will interfere with proper determination of exit status of child
900processes, Perl has reset the signal to its default value. This
901situation typically indicates that the parent program under which Perl
902may be running (e.g. cron) is being very careless.
0b5b802d 903
e2c0f81f
DG
904=item Can't kill a non-numeric process ID
905
906(F) Process identifiers must be (signed) integers. It is a fatal error to
907attempt to kill() an undefined, empty-string or otherwise non-numeric
908process identifier.
909
6df41af2 910=item Can't "last" outside a loop block
4633a7c4 911
6df41af2 912(F) A "last" statement was executed to break out of the current block,
be771a83
GS
913except that there's this itty bitty problem called there isn't a current
914block. Note that an "if" or "else" block doesn't count as a "loopish"
915block, as doesn't a block given to sort(), map() or grep(). You can
916usually double the curlies to get the same effect though, because the
917inner curlies will be considered a block that loops once. See
918L<perlfunc/last>.
4633a7c4 919
2c7d6b9c
RGS
920=item Can't linearize anonymous symbol table
921
922(F) Perl tried to calculate the method resolution order (MRO) of a
923package, but failed because the package stash has no name.
924
b8170e59
JB
925=item Can't load '%s' for module %s
926
6903afa2
FC
927(F) The module you tried to load failed to load a dynamic extension.
928This may either mean that you upgraded your version of perl to one
929that is incompatible with your old dynamic extensions (which is known
930to happen between major versions of perl), or (more likely) that your
931dynamic extension was built against an older version of the library
932that is installed on your system. You may need to rebuild your old
933dynamic extensions.
b8170e59 934
748a9306
LW
935=item Can't localize lexical variable %s
936
2ba9eb46 937(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
938lexical variable using "my" or "state". This is not allowed. If you
939want to localize a package variable of the same name, qualify it with
940the package name.
748a9306 941
6df41af2 942=item Can't localize through a reference
4727527e 943
6df41af2
GS
944(F) You said something like C<local $$ref>, which Perl can't currently
945handle, because when it goes to restore the old value of whatever $ref
be771a83 946pointed to after the scope of the local() is finished, it can't be sure
64977eb6 947that $ref will still be a reference.
4727527e 948
ea071790 949=item Can't locate %s
ec889f3a 950
fa816bf3
FC
951(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
952Perl looks for the file in all the locations mentioned in @INC, unless
953the file name included the full path to the file. Perhaps you need
954to set the PERL5LIB or PERL5OPT environment variable to say where the
955extra library is, or maybe the script needs to add the library name
be771a83
GS
956to @INC. Or maybe you just misspelled the name of the file. See
957L<perlfunc/require> and L<lib>.
a0d0e21e 958
6df41af2
GS
959=item Can't locate auto/%s.al in @INC
960
be771a83
GS
961(F) A function (or method) was called in a package which allows
962autoload, but there is no function to autoload. Most probable causes
963are a misprint in a function/method name or a failure to C<AutoSplit>
964the file, say, by doing C<make install>.
6df41af2 965
b8170e59
JB
966=item Can't locate loadable object for module %s in @INC
967
968(F) The module you loaded is trying to load an external library, like
d70d8e57 969for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
970unable to locate this library. See L<DynaLoader>.
971
a0d0e21e
LW
972=item Can't locate object method "%s" via package "%s"
973
974(F) You called a method correctly, and it correctly indicated a package
975functioning as a class, but that package doesn't define that particular
2ba9eb46 976method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 977
8af56b9d
FC
978=item Can't locate object method "%s" via package "%s" (perhaps you forgot
979to load "%s"?)
980
981(F) You called a method on a class that did not exist, and the method
982could not be found in UNIVERSAL. This often means that a method
983requires a package that has not been loaded.
984
a0d0e21e
LW
985=item Can't locate package %s for @%s::ISA
986
be771a83
GS
987(W syntax) The @ISA array contained the name of another package that
988doesn't seem to exist.
a0d0e21e 989
2f7da168
RK
990=item Can't locate PerlIO%s
991
992(F) You tried to use in open() a PerlIO layer that does not exist,
993e.g. open(FH, ">:nosuchlayer", "somefile").
994
f4ad53f4 995=item Can't make list assignment to %ENV on this system
3e3baf6d 996
be771a83
GS
997(F) List assignment to %ENV is not supported on some systems, notably
998VMS.
3e3baf6d 999
cd40cd58
NC
1000=item Can't make loaded symbols global on this platform while loading %s
1001
ff9c1ae8 1002(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1003that symbols from the stated file are made available globally within the
1004process, but that functionality is not available on this platform. Whilst
1005the module likely will still work, this may prevent the perl interpreter
1006from loading other XS-based extensions which need to link directly to
1007functions defined in the C or XS code in the stated file.
1008
a0d0e21e
LW
1009=item Can't modify %s in %s
1010
be771a83
GS
1011(F) You aren't allowed to assign to the item indicated, or otherwise try
1012to change it, such as with an auto-increment.
a0d0e21e 1013
54310121 1014=item Can't modify nonexistent substring
a0d0e21e
LW
1015
1016(P) The internal routine that does assignment to a substr() was handed
1017a NULL.
1018
6df41af2
GS
1019=item Can't modify non-lvalue subroutine call
1020
1021(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1022such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1023
5f05dabc 1024=item Can't msgrcv to read-only var
a0d0e21e 1025
5f05dabc 1026(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1027buffer.
1028
6df41af2
GS
1029=item Can't "next" outside a loop block
1030
1031(F) A "next" statement was executed to reiterate the current block, but
1032there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1033count as a "loopish" block, as doesn't a block given to sort(), map() or
1034grep(). You can usually double the curlies to get the same effect
1035though, because the inner curlies will be considered a block that loops
1036once. See L<perlfunc/next>.
6df41af2 1037
a0d0e21e
LW
1038=item Can't open %s: %s
1039
c47ff5f1 1040(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1041filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1042switches, or explicitly, failed for the indicated reason. Usually
1043this is because you don't have read permission for a file which
1044you named on the command line.
1045
1046(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1047your operating system's equivalent) could not be opened.
a0d0e21e 1048
9a869a14
RGS
1049=item Can't open a reference
1050
1051(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1052using the 3-arg open() syntax:
9a869a14
RGS
1053
1054 open FH, '>', $ref;
1055
1056but your version of perl is compiled without perlio, and this form of
1057open is not supported.
1058
a0d0e21e
LW
1059=item Can't open bidirectional pipe
1060
be771a83
GS
1061(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1062You can try any of several modules in the Perl library to do this, such
1063as IPC::Open2. Alternately, direct the pipe's output to a file using
1064">", and then read it in under a different file handle.
a0d0e21e 1065
748a9306
LW
1066=item Can't open error file %s as stderr
1067
be771a83
GS
1068(F) An error peculiar to VMS. Perl does its own command line
1069redirection, and couldn't open the file specified after '2>' or '2>>' on
1070the command line for writing.
748a9306
LW
1071
1072=item Can't open input file %s as stdin
1073
be771a83
GS
1074(F) An error peculiar to VMS. Perl does its own command line
1075redirection, and couldn't open the file specified after '<' on the
1076command line for reading.
748a9306
LW
1077
1078=item Can't open output file %s as stdout
1079
be771a83
GS
1080(F) An error peculiar to VMS. Perl does its own command line
1081redirection, and couldn't open the file specified after '>' or '>>' on
1082the command line for writing.
748a9306
LW
1083
1084=item Can't open output pipe (name: %s)
1085
be771a83
GS
1086(P) An error peculiar to VMS. Perl does its own command line
1087redirection, and couldn't open the pipe into which to send data destined
1088for stdout.
748a9306 1089
3b1cf97d 1090=item Can't open perl script "%s": %s
a0d0e21e
LW
1091
1092(F) The script you specified can't be opened for the indicated reason.
1093
fa3aa65a
JC
1094If you're debugging a script that uses #!, and normally relies on the
1095shell's $PATH search, the -S option causes perl to do that search, so
1096you don't have to type the path or C<`which $scriptname`>.
1097
6df41af2
GS
1098=item Can't read CRTL environ
1099
1100(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1101from the CRTL's internal environment array and discovered the array was
1102missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1103or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1104searched.
6df41af2 1105
6df41af2
GS
1106=item Can't "redo" outside a loop block
1107
1108(F) A "redo" statement was executed to restart the current block, but
1109there isn't a current block. Note that an "if" or "else" block doesn't
1110count as a "loopish" block, as doesn't a block given to sort(), map()
1111or grep(). You can usually double the curlies to get the same effect
1112though, because the inner curlies will be considered a block that
1113loops once. See L<perlfunc/redo>.
1114
64977eb6 1115=item Can't remove %s: %s, skipping file
10f9c03d 1116
be771a83
GS
1117(S inplace) You requested an inplace edit without creating a backup
1118file. Perl was unable to remove the original file to replace it with
1119the modified file. The file was left unmodified.
10f9c03d 1120
a0d0e21e
LW
1121=item Can't rename %s to %s: %s, skipping file
1122
e476b1b5 1123(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1124probably because you don't have write permission to the directory.
a0d0e21e 1125
748a9306
LW
1126=item Can't reopen input pipe (name: %s) in binary mode
1127
be771a83
GS
1128(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1129to reopen it to accept binary data. Alas, it failed.
748a9306 1130
4f12ec0e
FC
1131=item Can't reset %ENV on this system
1132
1133(F) You called C<reset('E')> or similar, which tried to reset
1134all variables in the current package beginning with "E". In
1135the main package, that includes %ENV. Resetting %ENV is not
1136supported on some systems, notably VMS.
1137
fe13d51d 1138=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1139
1fa582fa
FC
1140(F)(P) Error resolving overloading specified by a method name (as
1141opposed to a subroutine reference): no such method callable via the
1142package. If the method name is C<???>, this is an internal error.
6df41af2 1143
cd06dffe
GS
1144=item Can't return %s from lvalue subroutine
1145
be771a83
GS
1146(F) Perl detected an attempt to return illegal lvalues (such as
1147temporary or readonly values) from a subroutine used as an lvalue. This
1148is not allowed.
cd06dffe 1149
96ebfdd7
RK
1150=item Can't return outside a subroutine
1151
1152(F) The return statement was executed in mainline code, that is, where
1153there was no subroutine call to return out of. See L<perlsub>.
1154
78f9721b
SM
1155=item Can't return %s to lvalue scalar context
1156
6903afa2
FC
1157(F) You tried to return a complete array or hash from an lvalue
1158subroutine, but you called the subroutine in a way that made Perl
1159think you meant to return only one value. You probably meant to
1160write parentheses around the call to the subroutine, which tell
1161Perl that the call should be in list context.
78f9721b 1162
a0d0e21e
LW
1163=item Can't stat script "%s"
1164
be771a83
GS
1165(P) For some reason you can't fstat() the script even though you have it
1166open already. Bizarre.
a0d0e21e 1167
a0d0e21e
LW
1168=item Can't take log of %g
1169
fb73857a 1170(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1171negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1172standard with Perl, though, if you really want to do that for the
1173negative numbers.
a0d0e21e
LW
1174
1175=item Can't take sqrt of %g
1176
1177(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1178negative number. There's a Math::Complex package that comes standard
1179with Perl, though, if you really want to do that.
a0d0e21e
LW
1180
1181=item Can't undef active subroutine
1182
1183(F) You can't undefine a routine that's currently running. You can,
1184however, redefine it while it's running, and you can even undef the
1185redefined subroutine while the old routine is running. Go figure.
1186
c81225bc 1187=item Can't upgrade %s (%d) to %d
a0d0e21e 1188
be771a83
GS
1189(P) The internal sv_upgrade routine adds "members" to an SV, making it
1190into a more specialized kind of SV. The top several SV types are so
1191specialized, however, that they cannot be interconverted. This message
1192indicates that such a conversion was attempted.
a0d0e21e 1193
6651ba0b
FC
1194=item Can't use '%c' after -mname
1195
1196(F) You tried to call perl with the B<-m> switch, but you put something
1197other than "=" after the module name.
1198
1f1ec7b5
KW
1199=item Can't use a hash as a reference
1200
1201(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1202C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1203<= 5.22.0 used to allow this syntax, but shouldn't
1204have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1205
1206=item Can't use an array as a reference
1207
1208(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1209C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1210used to allow this syntax, but shouldn't have. This
1211was deprecated in perl 5.6.1.
1f1ec7b5 1212
1db89ea5
BS
1213=item Can't use anonymous symbol table for method lookup
1214
e27ad1f2 1215(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1216table that doesn't have a name. Symbol tables can become anonymous
1217for example by undefining stashes: C<undef %Some::Package::>.
1218
96ebfdd7
RK
1219=item Can't use an undefined value as %s reference
1220
1221(F) A value used as either a hard reference or a symbolic reference must
1222be a defined value. This helps to delurk some insidious errors.
1223
6df41af2
GS
1224=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1225
be771a83
GS
1226(F) Only hard references are allowed by "strict refs". Symbolic
1227references are disallowed. See L<perlref>.
6df41af2 1228
90b75b61 1229=item Can't use %! because Errno.pm is not available
1d2dff63 1230
20561843 1231(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1232Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1233provide symbolic names for C<$!> errno values.
1234
1109a392
MHM
1235=item Can't use both '<' and '>' after type '%c' in %s
1236
1237(F) A type cannot be forced to have both big-endian and little-endian
1238byte-order at the same time, so this combination of modifiers is not
1239allowed. See L<perlfunc/pack>.
1240
e35475de
KW
1241=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1242
1243(F) defined() is not useful on arrays because it
1244checks for an undefined I<scalar> value. If you want to see if the
1245array is empty, just use C<if (@array) { # not empty }> for example.
1246
1247=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1248
1249(F) C<defined()> is not usually right on hashes.
1250
1251Although C<defined %hash> is false on a plain not-yet-used hash, it
1252becomes true in several non-obvious circumstances, including iterators,
1253weak references, stash names, even remaining true after C<undef %hash>.
1254These things make C<defined %hash> fairly useless in practice, so it now
1255generates a fatal error.
1256
1257If a check for non-empty is what you wanted then just put it in boolean
1258context (see L<perldata/Scalar values>):
1259
1260 if (%hash) {
1261 # not empty
1262 }
1263
1264If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1265variable exists then that's never really been reliable, and isn't
1266a good way to enquire about the features of a package, or whether
1267it's loaded, etc.
1268
6df41af2
GS
1269=item Can't use %s for loop variable
1270
be771a83
GS
1271(F) Only a simple scalar variable may be used as a loop variable on a
1272foreach.
6df41af2 1273
aab6a793 1274=item Can't use global %s in "%s"
6df41af2 1275
be771a83
GS
1276(F) You tried to declare a magical variable as a lexical variable. This
1277is not allowed, because the magic can be tied to only one location
1278(namely the global variable) and it would be incredibly confusing to
1279have variables in your program that looked like magical variables but
6df41af2
GS
1280weren't.
1281
6d3b25aa
RGS
1282=item Can't use '%c' in a group with different byte-order in %s
1283
1284(F) You attempted to force a different byte-order on a type
1285that is already inside a group with a byte-order modifier.
1286For example you cannot force little-endianness on a type that
1287is inside a big-endian group.
1288
c07a80fd
PP
1289=item Can't use "my %s" in sort comparison
1290
1291(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1292You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1293and the variable had earlier been declared as a lexical variable.
1294Either qualify the sort variable with the package name, or rename the
1295lexical variable.
1296
a0d0e21e
LW
1297=item Can't use %s ref as %s ref
1298
1299(F) You've mixed up your reference types. You have to dereference a
1300reference of the type needed. You can use the ref() function to
1301test the type of the reference, if need be.
1302
748a9306 1303=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1304
5e634d20
FC
1305=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1306
b41bf23f
FC
1307(F) You've told Perl to dereference a string, something which
1308C<use strict> blocks to prevent it happening accidentally. See
1309L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1310in a double-quoted string immediately before interpolating a variable,
1311for example in C<"user @$twitter_id">, which says to treat the contents
1312of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1313symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1314
748a9306
LW
1315=item Can't use subscript on %s
1316
1317(F) The compiler tried to interpret a bracketed expression as a
1318subscript. But to the left of the brackets was an expression that
209e7cf1 1319didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1320
6df41af2
GS
1321=item Can't use \%c to mean $%c in expression
1322
75b44862
GS
1323(W syntax) In an ordinary expression, backslash is a unary operator that
1324creates a reference to its argument. The use of backslash to indicate a
1325backreference to a matched substring is valid only as part of a regular
be771a83
GS
1326expression pattern. Trying to do this in ordinary Perl code produces a
1327value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1328instead.
6df41af2 1329
810b8aa5
GS
1330=item Can't weaken a nonreference
1331
1332(F) You attempted to weaken something that was not a reference. Only
1333references can be weakened.
1334
fc7debfb
FC
1335=item Can't "when" outside a topicalizer
1336
1337(F) You have used a when() block that is neither inside a C<foreach>
1338loop nor a C<given> block. (Note that this error is issued on exit
1339from the C<when> block, so you won't get the error if the match fails,
1340or if you use an explicit C<continue>.)
1341
5f05dabc 1342=item Can't x= to read-only value
a0d0e21e 1343
be771a83
GS
1344(F) You tried to repeat a constant value (often the undefined value)
1345with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1346Perhaps you need to copy the value to a temporary, and repeat that.
1347
a04e6aad 1348=item Character following "\c" must be printable ASCII
f9d13529 1349
7357bd17 1350(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1351
727b6379 1352Note that ASCII characters that don't map to control characters are
7357bd17 1353discouraged, and will generate the warning (when enabled)
727b6379 1354L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1355
f337b084 1356=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1357
1358(W pack) You said
1359
1360 pack("C", $x)
1361
1362where $x is either less than 0 or more than 255; the C<"C"> format is
1363only for encoding native operating system characters (ASCII, EBCDIC,
1364and so on) and not for Unicode characters, so Perl behaved as if you meant
1365
1366 pack("C", $x & 255)
1367
1368If you actually want to pack Unicode codepoints, use the C<"U"> format
1369instead.
1370
f337b084 1371=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1372
1373(W pack) You said
1374
1375 pack("c", $x)
1376
1377where $x is either less than -128 or more than 127; the C<"c"> format
1378is only for encoding native operating system characters (ASCII, EBCDIC,
1379and so on) and not for Unicode characters, so Perl behaved as if you meant
1380
1381 pack("c", $x & 255);
1382
1383If you actually want to pack Unicode codepoints, use the C<"U"> format
1384instead.
1385
f337b084
TH
1386=item Character in '%c' format wrapped in unpack
1387
1388(W unpack) You tried something like
1389
1390 unpack("H", "\x{2a1}")
1391
1a147d38 1392where the format expects to process a byte (a character with a value
6903afa2
FC
1393below 256), but a higher value was provided instead. Perl uses the
1394value modulus 256 instead, as if you had provided:
f337b084
TH
1395
1396 unpack("H", "\x{a1}")
1397
5a25739d
FC
1398=item Character in 'W' format wrapped in pack
1399
1400(W pack) You said
1401
1402 pack("U0W", $x)
1403
1404where $x is either less than 0 or more than 255. However, C<U0>-mode
1405expects all values to fall in the interval [0, 255], so Perl behaved
1406as if you meant:
1407
1408 pack("U0W", $x & 255)
1409
f337b084
TH
1410=item Character(s) in '%c' format wrapped in pack
1411
1412(W pack) You tried something like
1413
1414 pack("u", "\x{1f3}b")
1415
1a147d38 1416where the format expects to process a sequence of bytes (character with a
6903afa2 1417value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1418uses the character values modulus 256 instead, as if you had provided:
1419
1420 pack("u", "\x{f3}b")
1421
1422=item Character(s) in '%c' format wrapped in unpack
1423
1424(W unpack) You tried something like
1425
1426 unpack("s", "\x{1f3}b")
1427
1a147d38 1428where the format expects to process a sequence of bytes (character with a
6903afa2 1429value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1430uses the character values modulus 256 instead, as if you had provided:
1431
1432 unpack("s", "\x{f3}b")
1433
f51551f7
FC
1434=item charnames alias definitions may not contain a sequence of multiple spaces
1435
1436(F) You defined a character name which had multiple space characters
1437in a row. Change them to single spaces. Usually these names are
1438defined in the C<:alias> import argument to C<use charnames>, but they
1439could be defined by a translator installed into C<$^H{charnames}>. See
1440L<charnames/CUSTOM ALIASES>.
1441
1442=item charnames alias definitions may not contain trailing white-space
1443
1444(F) You defined a character name which ended in a space
1445character. Remove the trailing space(s). Usually these names are
1446defined in the C<:alias> import argument to C<use charnames>, but they
1447could be defined by a translator installed into C<$^H{charnames}>.
1448See L<charnames/CUSTOM ALIASES>.
1449
1450=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1451
1452(D deprecated, regexp) The \C character class is deprecated, and will
1453become a compile-time error in a future release of perl (tentatively
1454v5.24). This construct allows you to match a single byte of what makes up
1455a multi-byte single UTF8 character, and breaks encapsulation. It is
1456currently also very buggy. If you really need to process the individual
1457bytes, you probably want to convert your string to one where each
1458underlying byte is stored as a character, with utf8::encode().
1459
f866a7cd
FC
1460=item "\c%c" is more clearly written simply as "%s"
1461
1462(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1463non-printable characters. You used it for a printable one, which
1464is better written as simply itself, perhaps preceded by a backslash
1465for non-word characters. Doing it the way you did is not portable
1466between ASCII and EBCDIC platforms.
f866a7cd 1467
6651ba0b
FC
1468=item Cloning substitution context is unimplemented
1469
1470(F) Creating a new thread inside the C<s///> operator is not supported.
1471
abc7ecad
SP
1472=item closedir() attempted on invalid dirhandle %s
1473
1474(W io) The dirhandle you tried to close is either closed or not really
1475a dirhandle. Check your control flow.
1476
5a25739d
FC
1477=item close() on unopened filehandle %s
1478
1479(W unopened) You tried to close a filehandle that was never opened.
1480
541ed3a9
FC
1481=item Closure prototype called
1482
1483(F) If a closure has attributes, the subroutine passed to an attribute
1484handler is the prototype that is cloned when a new closure is created.
1485This subroutine cannot be called.
1486
49704364
LW
1487=item Code missing after '/'
1488
6903afa2
FC
1489(F) You had a (sub-)template that ends with a '/'. There must be
1490another template code following the slash. See L<perlfunc/pack>.
49704364 1491
5a25739d
FC
1492=item Code point 0x%X is not Unicode, may not be portable
1493
2d88a86a 1494(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1495of U+10FFFF.
1496
1497Perl allows strings to contain a superset of Unicode code points, up
1498to the limit of what is storable in an unsigned integer on your system,
1499but these may not be accepted by other languages/systems. At one time,
1500it was legal in some standards to have code points up to 0x7FFF_FFFF,
1501but not higher. Code points above 0xFFFF_FFFF require larger than a
150232 bit word.
0876b9a0 1503
6df41af2
GS
1504=item %s: Command not found
1505
a892b81a 1506(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1507instead of Perl. Check the #! line, or manually feed your script into
1508Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1509
1510 #!/usr/bin/perl -w
6df41af2 1511
7a2e2cd6
PP
1512=item Compilation failed in require
1513
1514(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1515Perl uses this generic message when none of the errors that it
1516encountered were severe enough to halt compilation immediately.
7a2e2cd6 1517
c3464db5
DD
1518=item Complex regular subexpression recursion limit (%d) exceeded
1519
be771a83
GS
1520(W regexp) The regular expression engine uses recursion in complex
1521situations where back-tracking is required. Recursion depth is limited
1522to 32766, or perhaps less in architectures where the stack cannot grow
1523arbitrarily. ("Simple" and "medium" situations are handled without
1524recursion and are not subject to a limit.) Try shortening the string
1525under examination; looping in Perl code (e.g. with C<while>) rather than
1526in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1527that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1528on I<Mastering Regular Expressions>.)
c3464db5 1529
69282e91 1530=item connect() on closed socket %s
a0d0e21e 1531
be771a83
GS
1532(W closed) You tried to do a connect on a closed socket. Did you forget
1533to check the return value of your socket() call? See
1534L<perlfunc/connect>.
a0d0e21e 1535
e21e7c6a
FC
1536=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1537
1538(F) The subroutine registered to handle constant overloading
1539(see L<overload>) or a custom charnames handler (see
1540L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1541
1542=item Constant(%s): $^H{%s} is not defined
1543
1544(F) The parser found inconsistencies while attempting to define an
1545overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1546L<overload> pragma?
e21e7c6a 1547
779c5bc9
GS
1548=item Constant is not %s reference
1549
1550(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1551is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1552The message indicates the type of reference that was expected. This
be771a83 1553usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1554See L<perlsub/"Constant Functions"> and L<constant>.
1555
4cee8e80
CS
1556=item Constant subroutine %s redefined
1557
aeb94125
FC
1558(W redefine)(S) You redefined a subroutine which had previously
1559been eligible for inlining. See L<perlsub/"Constant Functions">
1560for commentary and workarounds.
4cee8e80 1561
9607fc9c
PP
1562=item Constant subroutine %s undefined
1563
be771a83
GS
1564(W misc) You undefined a subroutine which had previously been eligible
1565for inlining. See L<perlsub/"Constant Functions"> for commentary and
1566workarounds.
9607fc9c 1567
5a25739d
FC
1568=item Constant(%s) unknown
1569
1570(F) The parser found inconsistencies either while attempting
1571to define an overloaded constant, or when trying to find the
1572character name specified in the C<\N{...}> escape. Perhaps you
1573forgot to load the corresponding L<overload> pragma?.
1574
e7ea3e70
IZ
1575=item Copy method did not return a reference
1576
6903afa2 1577(F) The method which overloads "=" is buggy. See
13a2d996 1578L<overload/Copy Constructor>.
e7ea3e70 1579
4aaa4757
FC
1580=item &CORE::%s cannot be called directly
1581
1582(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1583with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1584in this package cannot yet be called that way, but must be
1585called as barewords. Something like this will work:
1586
1587 BEGIN { *shove = \&CORE::push; }
1588 shove @array, 1,2,3; # pushes on to @array
1589
6798c92b
GS
1590=item CORE::%s is not a keyword
1591
1592(F) The CORE:: namespace is reserved for Perl keywords.
1593
675fa9ff
FC
1594=item Corrupted regexp opcode %d > %d
1595
1596(P) This is either an error in Perl, or, if you're using
1597one, your L<custom regular expression engine|perlreapi>. If not the
1598latter, report the problem through the L<perlbug> utility.
1599
a0d0e21e
LW
1600=item corrupted regexp pointers
1601
1602(P) The regular expression engine got confused by what the regular
1603expression compiler gave it.
1604
1605=item corrupted regexp program
1606
be771a83
GS
1607(P) The regular expression engine got passed a regexp program without a
1608valid magic number.
a0d0e21e 1609
de42a5a9 1610=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1611
1612(P) The malloc package that comes with Perl had an internal failure.
1613
49704364
LW
1614=item Count after length/code in unpack
1615
1616(F) You had an unpack template indicating a counted-length string, but
1617you have also specified an explicit size for the string. See
1618L<perlfunc/pack>.
1619
f2cccb4c
KW
1620=for comment
1621The following are used in lib/diagnostics.t for testing two =items that
1622share the same description. Changes here need to be propagated to there
1623
6651ba0b
FC
1624=item Deep recursion on anonymous subroutine
1625
a0d0e21e
LW
1626=item Deep recursion on subroutine "%s"
1627
be771a83
GS
1628(W recursion) This subroutine has called itself (directly or indirectly)
1629100 times more than it has returned. This probably indicates an
1630infinite recursion, unless you're writing strange benchmark programs, in
1631which case it indicates something else.
a0d0e21e 1632
aad1d01f
NC
1633This threshold can be changed from 100, by recompiling the F<perl> binary,
1634setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1635
e0e4a6e3
FC
1636=item (?(DEFINE)....) does not allow branches in regex; marked by
1637S<<-- HERE> in m/%s/
bcb95744 1638
6903afa2 1639(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1640most likely cause of this error is that you left out a parenthesis inside
1641of the C<....> part.
1642
9e3ec65c 1643The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1644discovered.
1645
62658f4d
PM
1646=item %s defines neither package nor VERSION--version check failed
1647
1648(F) You said something like "use Module 42" but in the Module file
1649there are neither package declarations nor a C<$VERSION>.
1650
36447869
FC
1651=item delete argument is index/value array slice, use array slice
1652
1653(F) You used index/value array slice syntax (C<%array[...]>) as
1654the argument to C<delete>. You probably meant C<@array[...]> with
1655an @ symbol instead.
1656
1657=item delete argument is key/value hash slice, use hash slice
1658
1659(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1660C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1661
0ffcbc25
FC
1662=item delete argument is not a HASH or ARRAY element or slice
1663
4a0af295 1664(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1665such as:
1666
1667 $foo{$bar}
1668 $ref->{"susie"}[12]
1669
1670or a hash or array slice, such as:
1671
1672 @foo[$bar, $baz, $xyzzy]
1673 @{$ref->[12]}{"susie", "queue"}
1674
fc36a67e
PP
1675=item Delimiter for here document is too long
1676
be771a83
GS
1677(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1678long for Perl to handle. You have to be seriously twisted to write code
1679that triggers this error.
fc36a67e 1680
6d3b25aa
RGS
1681=item Deprecated use of my() in false conditional
1682
fa816bf3
FC
1683(D deprecated) You used a declaration similar to C<my $x if 0>. There
1684has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1685not to be cleared at scope exit when its declaration includes a false
6903afa2 1686conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1687static variable. Since we intend to fix this bug, we don't want people
6903afa2 1688relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1689declaring the variable in a separate block outside the function, eg
36fb85f3 1690
6d3b25aa
RGS
1691 sub f { my $x if 0; return $x++ }
1692
1693becomes
1694
1695 { my $x; sub f { return $x++ } }
1696
ea9d9ebc 1697Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1698lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1699
1700 sub f { state $x; return $x++ }
1701
500ab966
RGS
1702=item DESTROY created new reference to dead object '%s'
1703
1704(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1705just being DESTROYed. Perl is confused, and prefers to abort rather
1706than to create a dangling reference.
500ab966 1707
3cdd684c
TP
1708=item Did not produce a valid header
1709
1710See Server error.
1711
6df41af2
GS
1712=item %s did not return a true value
1713
1714(F) A required (or used) file must return a true value to indicate that
1715it compiled correctly and ran its initialization code correctly. It's
1716traditional to end such a file with a "1;", though any true value would
1717do. See L<perlfunc/require>.
1718
cc507455 1719=item (Did you mean &%s instead?)
4633a7c4 1720
413ff9f6
FC
1721(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1722some such.
4633a7c4 1723
cc507455 1724=item (Did you mean "local" instead of "our"?)
33633739 1725
be771a83
GS
1726(W misc) Remember that "our" does not localize the declared global
1727variable. You have declared it again in the same lexical scope, which
1728seems superfluous.
33633739 1729
cc507455 1730=item (Did you mean $ or @ instead of %?)
a0d0e21e 1731
be771a83
GS
1732(W) You probably said %hash{$key} when you meant $hash{$key} or
1733@hash{@keys}. On the other hand, maybe you just meant %hash and got
1734carried away.
748a9306 1735
7e1af8bc 1736=item Died
5f05dabc
PP
1737
1738(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1739you called it with no args and C<$@> was empty.
5f05dabc 1740
3cdd684c
TP
1741=item Document contains no data
1742
1743See Server error.
1744
62658f4d
PM
1745=item %s does not define %s::VERSION--version check failed
1746
1747(F) You said something like "use Module 42" but the Module did not
943fc58e 1748define a C<$VERSION>.
62658f4d 1749
49704364
LW
1750=item '/' does not take a repeat count
1751
1752(F) You cannot put a repeat count of any kind right after the '/' code.
1753See L<perlfunc/pack>.
1754
95cb0d72
FC
1755=item Don't know how to get file name
1756
1757(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1758somehow called on another platform. This should not happen.
1759
4021c788 1760=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1761
1762(P) The internal handling of magical variables has been cursed.
1763
1764=item do_study: out of memory
1765
1766(P) This should have been caught by safemalloc() instead.
1767
6df41af2
GS
1768=item (Do you need to predeclare %s?)
1769
56da5a46
RGS
1770(S syntax) This is an educated guess made in conjunction with the message
1771"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1772name is being referenced that hasn't been declared yet. This may be
1773because of ordering problems in your file, or because of a missing
be771a83
GS
1774"sub", "package", "require", or "use" statement. If you're referencing
1775something that isn't defined yet, you don't actually have to define the
1776subroutine or package before the current location. You can use an empty
1777"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1778
ac206dc8
RGS
1779=item dump() better written as CORE::dump()
1780
1781(W misc) You used the obsolescent C<dump()> built-in function, without fully
1782qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1783
84d78eb7
YO
1784=item dump is not supported
1785
1786(F) Your machine doesn't support dump/undump.
1787
a0d0e21e
LW
1788=item Duplicate free() ignored
1789
be771a83
GS
1790(S malloc) An internal routine called free() on something that had
1791already been freed.
a0d0e21e 1792
1109a392
MHM
1793=item Duplicate modifier '%c' after '%c' in %s
1794
35f0cd76
FC
1795(W unpack) You have applied the same modifier more than once after a
1796type in a pack template. See L<perlfunc/pack>.
1109a392 1797
0953b66b
FC
1798=item each on reference is experimental
1799
0773cb3e
FC
1800(S experimental::autoderef) C<each> with a scalar argument is experimental
1801and may change or be removed in a future Perl version. If you want to
1802take the risk of using this feature, simply disable this warning:
0953b66b 1803
d401967c 1804 no warnings "experimental::autoderef";
0953b66b 1805
4633a7c4
LW
1806=item elseif should be elsif
1807
fa816bf3
FC
1808(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1809it's ugly. Your code will be interpreted as an attempt to call a method
1810named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1811unlikely to be what you want.
1812
e0e4a6e3 1813=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1814
af6f566e 1815(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1816described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1817a regular expression without specifying the property name.
ab13f0c7 1818
85ab1d1d 1819=item entering effective %s failed
5ff3f7a4 1820
85ab1d1d 1821(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1822effective uids or gids failed.
1823
c038024b
RGS
1824=item %ENV is aliased to %s
1825
1826(F) You're running under taint mode, and the C<%ENV> variable has been
1827aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1828program's environment. This is potentially insecure.
c038024b 1829
748a9306
LW
1830=item Error converting file specification %s
1831
5f05dabc 1832(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1833specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1834single form when it must operate on them directly. Either you've passed
1835an invalid file specification to Perl, or you've found a case the
1836conversion routines don't handle. Drat.
748a9306 1837
ad19ef22 1838=item Eval-group in insecure regular expression
e4d48cc9 1839
be771a83
GS
1840(F) Perl detected tainted data when trying to compile a regular
1841expression that contains the C<(?{ ... })> zero-width assertion, which
1842is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1843
ad19ef22 1844=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1845
be771a83
GS
1846(F) Perl tried to compile a regular expression containing the
1847C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1848pattern contains interpolated values. Since that is a security risk,
1849it is not allowed. If you insist, you may still do this by using the
1850C<re 'eval'> pragma or by explicitly building the pattern from an
1851interpolated string at run time and using that in an eval(). See
1852L<perlre/(?{ code })>.
e4d48cc9 1853
ad19ef22 1854=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1855
be771a83
GS
1856(F) A regular expression contained the C<(?{ ... })> zero-width
1857assertion, but that construct is only allowed when the C<use re 'eval'>
1858pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1859
e0e4a6e3
FC
1860=item EVAL without pos change exceeded limit in regex; marked by
1861S<<-- HERE> in m/%s/
1a147d38
YO
1862
1863(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1864any text. Restructure the pattern so that text is consumed.
1a147d38 1865
9e3ec65c 1866The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1867discovered.
1868
fc36a67e
PP
1869=item Excessively long <> operator
1870
1871(F) The contents of a <> operator may not exceed the maximum size of a
1872Perl identifier. If you're just trying to glob a long list of
1873filenames, try using the glob() operator, or put the filenames into a
1874variable and glob that.
1875
ed9aa3b7
SG
1876=item exec? I'm not *that* kind of operating system
1877
af8bb25a 1878(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1879OS. See L<perlport>.
ed9aa3b7 1880
fe13d51d 1881=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1882
1883(F) The final summary message when a Perl compilation fails.
1884
0ffcbc25
FC
1885=item exists argument is not a HASH or ARRAY element or a subroutine
1886
4a0af295 1887(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1888subroutine with an ampersand, such as:
1889
1890 $foo{$bar}
1891 $ref->{"susie"}[12]
1892 &do_something
1893
1894=item exists argument is not a subroutine name
1895
ccfc2567
FC
1896(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1897and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1898
a0d0e21e
LW
1899=item Exiting eval via %s
1900
be771a83
GS
1901(W exiting) You are exiting an eval by unconventional means, such as a
1902goto, or a loop control statement.
e476b1b5
GS
1903
1904=item Exiting format via %s
1905
9a2ff54b 1906(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1907goto, or a loop control statement.
a0d0e21e 1908
0a753a76
PP
1909=item Exiting pseudo-block via %s
1910
be771a83
GS
1911(W exiting) You are exiting a rather special block construct (like a
1912sort block or subroutine) by unconventional means, such as a goto, or a
1913loop control statement. See L<perlfunc/sort>.
0a753a76 1914
a0d0e21e
LW
1915=item Exiting subroutine via %s
1916
be771a83
GS
1917(W exiting) You are exiting a subroutine by unconventional means, such
1918as a goto, or a loop control statement.
a0d0e21e
LW
1919
1920=item Exiting substitution via %s
1921
be771a83
GS
1922(W exiting) You are exiting a substitution by unconventional means, such
1923as a return, a goto, or a loop control statement.
a0d0e21e 1924
e0e4a6e3 1925=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1926
675fa9ff 1927(F) You wrote something like
c608e803
KW
1928
1929 (?13
1930
1931to denote a capturing group of the form
1932L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1933but omitted the C<")">.
1934
e0e4a6e3 1935=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1936
8b6fbf55
FC
1937(F) The C<(?[...])> extended character class regular expression construct
1938only allows character classes (including character class escapes like
1939C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1940containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1941This allows a regular expression containing just C<(?[...])> to be
1942interpolated. If you see this error message, then you probably
1943have some other C<(?...)> construct inside your character class. See
1944L<perlrecharclass/Extended Bracketed Character Classes>.
1945
30d9c59b
Z
1946=item Experimental subroutine signatures not enabled
1947
1948(F) To use subroutine signatures, you must first enable them:
1949
caa35032 1950 no warnings "experimental::signatures";
30d9c59b
Z
1951 use feature "signatures";
1952 sub foo ($left, $right) { ... }
1953
6da34ecb
FC
1954=item Experimental "%s" subs not enabled
1955
1956(F) To use lexical subs, you must first enable them:
1957
1958 no warnings 'experimental::lexical_subs';
1959 use feature 'lexical_subs';
1960 my sub foo { ... }
1961
7b8d334a
GS
1962=item Explicit blessing to '' (assuming package main)
1963
be771a83
GS
1964(W misc) You are blessing a reference to a zero length string. This has
1965the effect of blessing the reference into the package main. This is
1966usually not what you want. Consider providing a default target package,
1967e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1968
6df41af2
GS
1969=item %s: Expression syntax
1970
be771a83
GS
1971(A) You've accidentally run your script through B<csh> instead of Perl.
1972Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1973
1974=item %s failed--call queue aborted
1975
3c10abe3
AG
1976(F) An untrapped exception was raised while executing a UNITCHECK,
1977CHECK, INIT, or END subroutine. Processing of the remainder of the
1978queue of such routines has been prematurely ended.
6df41af2 1979
e0e4a6e3 1980=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1981
98d31c73 1982(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1983character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1984in your false range is interpreted as a literal "-". In a C<(?[...])>
1985construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1986the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1987the problem was discovered. See L<perlre>.
73b437c8 1988
1b1ee2ef 1989=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1990
be771a83
GS
1991(P) An error peculiar to VMS. Something untoward happened in a VMS
1992system service or RTL routine; Perl's exit status should provide more
1993details. The filename in "at %s" and the line number in "line %d" tell
1994you which section of the Perl source code is distressed.
a0d0e21e
LW
1995
1996=item fcntl is not implemented
1997
1998(F) Your machine apparently doesn't implement fcntl(). What is this, a
1999PDP-11 or something?
2000
22846ab4
AB
2001=item FETCHSIZE returned a negative value
2002
2003(F) A tied array claimed to have a negative number of elements, which
2004is not possible.
2005
f337b084
TH
2006=item Field too wide in 'u' format in pack
2007
d8b5cc61 2008(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2009which can't encode values above 63. So there is no point in asking for
2010a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2011C<u63> as the format.
f337b084 2012
af8c498a 2013=item Filehandle %s opened only for input
a0d0e21e 2014
6c8d78fb
HS
2015(W io) You tried to write on a read-only filehandle. If you intended
2016it to be a read-write filehandle, you needed to open it with "+<" or
2017"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2018write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2019
af8c498a 2020=item Filehandle %s opened only for output
a0d0e21e 2021
6c8d78fb
HS
2022(W io) You tried to read from a filehandle opened only for writing, If
2023you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2024with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2025read from the file, use "<". See L<perlfunc/open>. Another possibility
2026is that you attempted to open filedescriptor 0 (also known as STDIN) for
2027output (maybe you closed STDIN earlier?).
97828cef
RGS
2028
2029=item Filehandle %s reopened as %s only for input
2030
2031(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2032as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2033previously.
2034
2035=item Filehandle STDIN reopened as %s only for output
2036
2037(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2038as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2039
2040=item Final $ should be \$ or $name
2041
2042(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2043a literal dollar sign, or was meant to introduce a variable name that
2044happens to be missing. So you have to put either the backslash or the
2045name.
a0d0e21e 2046
56e90b21
GS
2047=item flock() on closed filehandle %s
2048
be771a83 2049(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2050some time before now. Check your control flow. flock() operates on
be771a83
GS
2051filehandles. Are you attempting to call flock() on a dirhandle by the
2052same name?
56e90b21 2053
6df41af2
GS
2054=item Format not terminated
2055
2056(F) A format must be terminated by a line with a solitary dot. Perl got
2057to the end of your file without finding such a line.
2058
a0d0e21e
LW
2059=item Format %s redefined
2060
e476b1b5 2061(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2062
2063 {
271595cc 2064 no warnings 'redefine';
a0d0e21e
LW
2065 eval "format NAME =...";
2066 }
2067
a0d0e21e
LW
2068=item Found = in conditional, should be ==
2069
e476b1b5 2070(W syntax) You said
a0d0e21e
LW
2071
2072 if ($foo = 123)
2073
2074when you meant
2075
2076 if ($foo == 123)
2077
2078(or something like that).
2079
6df41af2
GS
2080=item %s found where operator expected
2081
56da5a46
RGS
2082(S syntax) The Perl lexer knows whether to expect a term or an operator.
2083If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2084operator, it gives you this warning. Usually it indicates that an
2085operator or delimiter was omitted, such as a semicolon.
6df41af2 2086
a0d0e21e
LW
2087=item gdbm store returned %d, errno %d, key "%s"
2088
2089(S) A warning from the GDBM_File extension that a store failed.
2090
2091=item gethostent not implemented
2092
2093(F) Your C library apparently doesn't implement gethostent(), probably
2094because if it did, it'd feel morally obligated to return every hostname
2095on the Internet.
2096
69282e91 2097=item get%sname() on closed socket %s
a0d0e21e 2098
be771a83
GS
2099(W closed) You tried to get a socket or peer socket name on a closed
2100socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2101
748a9306
LW
2102=item getpwnam returned invalid UIC %#o for user "%s"
2103
2104(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2105C<getpwnam> operator returned an invalid UIC.
2106
6df41af2
GS
2107=item getsockopt() on closed socket %s
2108
be771a83
GS
2109(W closed) You tried to get a socket option on a closed socket. Did you
2110forget to check the return value of your socket() call? See
6df41af2
GS
2111L<perlfunc/getsockopt>.
2112
0f539b13
BF
2113=item given is experimental
2114
675fa9ff
FC
2115(S experimental::smartmatch) C<given> depends on smartmatch, which
2116is experimental, so its behavior may change or even be removed
2117in any future release of perl. See the explanation under
2118L<perlsyn/Experimental Details on given and when>.
0f539b13 2119
68567d27
FC
2120=item Global symbol "%s" requires explicit package name (did you forget to
2121declare "my %s"?)
6df41af2 2122
a4edf47d 2123(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2124that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2125declared beforehand using "our", or explicitly qualified to say
2126which package the global variable is in (using "::").
6df41af2 2127
e476b1b5
GS
2128=item glob failed (%s)
2129
5ead438e 2130(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2131for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2132pattern that caused the external program to fail and exit with a
be771a83 2133nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2134resulted in a coredump, this may also mean that your csh (C shell)
2135is broken. If so, you should change all of the csh-related variables
2136in config.sh: If you have tcsh, make the variables refer to it as
2137if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2138all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2139think csh is missing. In either case, after editing config.sh, run
75b44862 2140C<./Configure -S> and rebuild Perl.
e476b1b5 2141
a0d0e21e
LW
2142=item Glob not terminated
2143
2144(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2145a term, so it's looking for the corresponding right angle bracket, and
2146not finding it. Chances are you left some needed parentheses out
2147earlier in the line, and you really meant a "less than".
a0d0e21e 2148
b35b96b6
JH
2149=item gmtime(%f) failed
2150
2151(W overflow) You called C<gmtime> with a number that it could not handle:
2152too large, too small, or NaN. The returned value is C<undef>.
2153
bcd05b94 2154=item gmtime(%f) too large
8b56d6ff 2155
e9200be3 2156(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2157it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2158date. This warning is also triggered with NaN (the special
fc003d4b
MS
2159not-a-number value).
2160
bcd05b94 2161=item gmtime(%f) too small
fc003d4b 2162
e9200be3 2163(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2164it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2165
6df41af2 2166=item Got an error from DosAllocMem
a0d0e21e 2167
6df41af2
GS
2168(P) An error peculiar to OS/2. Most probably you're using an obsolete
2169version of Perl, and this should not happen anyway.
a0d0e21e
LW
2170
2171=item goto must have label
2172
2173(F) Unlike with "next" or "last", you're not allowed to goto an
2174unspecified destination. See L<perlfunc/goto>.
2175
6651ba0b
FC
2176=item Goto undefined subroutine%s
2177
2178(F) You tried to call a subroutine with C<goto &sub> syntax, but
2179the indicated subroutine hasn't been defined, or if it was, it
2180has since been undefined.
2181
6fbc9859 2182=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2183S<<-- HERE> in m/%s/
1f4f6bf1
YO
2184
2185(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2186they must start with a non-digit word character. A common cause of
2187this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2188
5a25739d
FC
2189=item ()-group starts with a count
2190
2191(F) A ()-group started with a count. A count is supposed to follow
2192something: a template character or a ()-group. See L<perlfunc/pack>.
2193
fe13d51d 2194=item %s had compilation errors.
6df41af2
GS
2195
2196(F) The final summary message when a C<perl -c> fails.
2197
a0d0e21e
LW
2198=item Had to create %s unexpectedly
2199
be771a83
GS
2200(S internal) A routine asked for a symbol from a symbol table that ought
2201to have existed already, but for some reason it didn't, and had to be
2202created on an emergency basis to prevent a core dump.
a0d0e21e 2203
6df41af2
GS
2204=item %s has too many errors
2205
2206(F) The parser has given up trying to parse the program after 10 errors.
2207Further error messages would likely be uninformative.
2208
61e61fbc
JH
2209=item Hexadecimal float: exponent overflow
2210
d8f2b442 2211(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2212than the floating point supports.
2213
2214=item Hexadecimal float: exponent underflow
2215
d8f2b442 2216(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2217than the floating point supports.
2218
cf4f6003
JH
2219=item Hexadecimal float: internal error
2220
2221(F) Something went horribly bad in hexadecimal float handling.
2222
61e61fbc
JH
2223=item Hexadecimal float: mantissa overflow
2224
2225(W overflow) The hexadecimal floating point literal had more bits in
2226the mantissa (the part between the 0x and the exponent, also known as
2227the fraction or the significand) than the floating point supports.
2228
40bca5ae
JH
2229=item Hexadecimal float: precision loss
2230
2231(W overflow) The hexadecimal floating point had internally more
2232digits than could be output. This can be caused by unsupported
2233long double formats, or by 64-bit integers not being available
2234(needed to retrieve the digits under some configurations).
2235
2236=item Hexadecimal float: unsupported long double format
2237
2238(F) You have configured Perl to use long doubles but
d8f2b442 2239the internals of the long double format are unknown;
40bca5ae
JH
2240therefore the hexadecimal float output is impossible.
2241
252aa082
JH
2242=item Hexadecimal number > 0xffffffff non-portable
2243
e476b1b5 2244(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2245(4294967295) and therefore non-portable between systems. See
2246L<perlport> for more on portability concerns.
252aa082 2247
8903cb82
PP
2248=item Identifier too long
2249
2250(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2251about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2252names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2253of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2254
e0e4a6e3
FC
2255=item Ignoring zero length \N{} in character class in regex; marked by
2256S<<-- HERE> in m/%s/
fc8cd66c 2257
f3ba6905 2258(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2259zero-length sequence. When such an escape is used in a character class
2260its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2261been used, and the correct charname handler is in scope.
2262
6df41af2 2263=item Illegal binary digit %s
f675dbe5 2264
6df41af2 2265(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2266
6df41af2 2267=item Illegal binary digit %s ignored
a0d0e21e 2268
be771a83
GS
2269(W digit) You may have tried to use a digit other than 0 or 1 in a
2270binary number. Interpretation of the binary number stopped before the
2271offending digit.
a0d0e21e 2272
6597eb22
FC
2273=item Illegal character after '_' in prototype for %s : %s
2274
e4d150f1
FC
2275(W illegalproto) An illegal character was found in a prototype
2276declaration. The '_' in a prototype must be followed by a ';',
2277indicating the rest of the parameters are optional, or one of '@'
2278or '%', since those two will accept 0 or more final parameters.
6597eb22 2279
78d0fecf 2280=item Illegal character \%o (carriage return)
4fdae800 2281
d5898338 2282(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2283would any other whitespace, which means you should never see this error
2284when Perl was built using standard options. For some reason, your
2285version of Perl appears to have been built without this support. Talk
2286to your Perl administrator.
4fdae800 2287
d37a9538
ST
2288=item Illegal character in prototype for %s : %s
2289
197afce1 2290(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2291Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2292Perhaps you were trying to write a subroutine signature but didn't enable
2293that feature first (C<use feature 'signatures'>), so your signature was
2294instead interpreted as a bad prototype.
d37a9538 2295
904d85c5
RGS
2296=item Illegal declaration of anonymous subroutine
2297
2298(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2299you must always specify a block of code. See L<perlsub>.
904d85c5 2300
8e742a20
MHM
2301=item Illegal declaration of subroutine %s
2302
6903afa2 2303(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2304
a0d0e21e
LW
2305=item Illegal division by zero
2306
be771a83
GS
2307(F) You tried to divide a number by 0. Either something was wrong in
2308your logic, or you need to put a conditional in to guard against
2309meaningless input.
a0d0e21e 2310
6df41af2
GS
2311=item Illegal hexadecimal digit %s ignored
2312
be771a83
GS
2313(W digit) You may have tried to use a character other than 0 - 9 or
2314A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2315number stopped before the illegal character.
6df41af2 2316
a0d0e21e
LW
2317=item Illegal modulus zero
2318
be771a83
GS
2319(F) You tried to divide a number by 0 to get the remainder. Most
2320numbers don't take to this kindly.
a0d0e21e 2321
6df41af2 2322=item Illegal number of bits in vec
399388f4 2323
6df41af2
GS
2324(F) The number of bits in vec() (the third argument) must be a power of
2325two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2326
2327=item Illegal octal digit %s
a0d0e21e 2328
d1be9408 2329(F) You used an 8 or 9 in an octal number.
a0d0e21e 2330
399388f4 2331=item Illegal octal digit %s ignored
748a9306 2332
d1be9408 2333(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2334Interpretation of the octal number stopped before the 8 or 9.
748a9306 2335
e0e4a6e3 2336=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2337
675fa9ff 2338(F) You wrote something like
c608e803
KW
2339
2340 (?+foo)
2341
2342The C<"+"> is valid only when followed by digits, indicating a
2343capturing group. See
2344L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2345
375ed12a
JH
2346=item Illegal suidscript
2347
2348(F) The script run under suidperl was somehow illegal.
2349
fe13d51d 2350=item Illegal switch in PERL5OPT: -%c
6ff81951 2351
6df41af2 2352(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2353following switches: B<-[CDIMUdmtw]>.
6ff81951 2354
6df41af2 2355=item Ill-formed CRTL environ value "%s"
81e118e0 2356
75b44862 2357(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2358internal environ array, and encountered an element without the C<=>
2359delimiter used to separate keys from values. The element is ignored.
09bef843 2360
6df41af2 2361=item Ill-formed message in prime_env_iter: |%s|
54310121 2362
be771a83
GS
2363(W internal) A warning peculiar to VMS. Perl tried to read a logical
2364name or CLI symbol definition when preparing to iterate over %ENV, and
2365didn't see the expected delimiter between key and value, so the line was
2366ignored.
54310121 2367
6df41af2 2368=item (in cleanup) %s
9607fc9c 2369
be771a83
GS
2370(W misc) This prefix usually indicates that a DESTROY() method raised
2371the indicated exception. Since destructors are usually called by the
2372system at arbitrary points during execution, and often a vast number of
2373times, the warning is issued only once for any number of failures that
2374would otherwise result in the same message being repeated.
6df41af2 2375
be771a83
GS
2376Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2377also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2378
e0e4a6e3
FC
2379=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2380in m/%s/
0d0b4b3b 2381
675fa9ff 2382(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2383expression inside the construct was completely empty, or if there are
2384too many or few operands for the number of operators. Perl is not smart
2385enough to give you a more precise indication as to what is wrong.
2386
6fbc9859
MH
2387=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2388parent '%s'
2c7d6b9c
RGS
2389
2390(F) The method resolution order (MRO) of the given class is not
2391C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2392documentation in L<mro> for more information.
2393
979699d9
JH
2394=item In EBCDIC the v-string components cannot exceed 2147483647
2395
2396(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2397Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2398encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2399
6a2ed79a 2400=item Infinite recursion in regex
1a147d38
YO
2401
2402(F) You used a pattern that references itself without consuming any input
6903afa2 2403text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2404either consume text or fail.
2405
6dbe9451
NC
2406=item Initialization of state variables in list context currently forbidden
2407
6903afa2
FC
2408(F) Currently the implementation of "state" only permits the
2409initialization of scalar variables in scalar context. Re-write
2410C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2411context. Constructions such as C<state (@a) = foo()> will be
2412supported in a future perl release.
6dbe9451 2413
2186f873
FC
2414=item %%s[%s] in scalar context better written as $%s[%s]
2415
2416(W syntax) In scalar context, you've used an array index/value slice
2417(indicated by %) to select a single element of an array. Generally
2418it's better to ask for a scalar value (indicated by $). The difference
2419is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2420returns and when evaluating its argument, while C<%foo[&bar]> provides
2421a list context to its subscript, which can do weird things if you're
2422expecting only one subscript. When called in list context, it also
2423returns the index (what C<&bar> returns) in addition to the value.
2424
2425=item %%s{%s} in scalar context better written as $%s{%s}
2426
2427(W syntax) In scalar context, you've used a hash key/value slice
2428(indicated by %) to select a single element of a hash. Generally it's
2429better to ask for a scalar value (indicated by $). The difference
2430is that C<$foo{&bar}> always behaves like a scalar, both in the value
2431it returns and when evaluating its argument, while C<@foo{&bar}> and
2432provides a list context to its subscript, which can do weird things
2433if you're expecting only one subscript. When called in list context,
2434it also returns the key in addition to the value.
2435
a0d0e21e
LW
2436=item Insecure dependency in %s
2437
8b1a09fc 2438(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2439The tainting mechanism is turned on when you're running setuid or
2440setgid, or when you specify B<-T> to turn it on explicitly. The
2441tainting mechanism labels all data that's derived directly or indirectly
2442from the user, who is considered to be unworthy of your trust. If any
2443such data is used in a "dangerous" operation, you get this error. See
2444L<perlsec> for more information.
a0d0e21e
LW
2445
2446=item Insecure directory in %s
2447
be771a83
GS
2448(F) You can't use system(), exec(), or a piped open in a setuid or
2449setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2450the world. Also, the PATH must not contain any relative directory.
2451See L<perlsec>.
a0d0e21e 2452
62f468fc 2453=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2454
2455(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2456setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2457C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2458supplied (or potentially supplied) by the user. The script must set
2459the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2460
0e9be77f
DM
2461=item Insecure user-defined property %s
2462
2463(F) Perl detected tainted data when trying to compile a regular
2464expression that contains a call to a user-defined character property
2465function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2466See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2467
b9ef414d
FC
2468=item Integer overflow in format string for %s
2469
2470(F) The indexes and widths specified in the format string of C<printf()>
2471or C<sprintf()> are too large. The numbers must not overflow the size of
2472integers for your architecture.
2473
a7ae9550
GS
2474=item Integer overflow in %s number
2475
35928bc5 2476(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2477either as a literal or as an argument to hex() or oct() is too big for
2478your architecture, and has been converted to a floating point number.
2479On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2480representable without overflow is 0xFFFFFFFF, 037777777777, or
24810b11111111111111111111111111111111 respectively. Note that Perl
2482transparently promotes all numbers to a floating point representation
2483internally--subject to loss of precision errors in subsequent
2484operations.
bbce6d69 2485
fc89ca81
FC
2486=item Integer overflow in srand
2487
2488(S overflow) The number you have passed to srand is too big to fit
2489in your architecture's integer representation. The number has been
2490replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2491architectures). This means you may be getting less randomness than
2492you expect, because different random seeds above the maximum will
2493return the same sequence of random numbers.
2494
46314c13
JP
2495=item Integer overflow in version
2496
18da5252
FC
2497=item Integer overflow in version %d
2498
784d71ed
FC
2499(W overflow) Some portion of a version initialization is too large for
2500the size of integers for your architecture. This is not a warning
f084e84f 2501because there is no rational reason for a version to try and use an
784d71ed
FC
2502element larger than typically 2**32. This is usually caused by trying
2503to use some odd mathematical operation as a version, like 100/9.
46314c13 2504
e0e4a6e3 2505=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2506
2507(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2508The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2509discovered.
2510
748a9306
LW
2511=item Internal inconsistency in tracking vforks
2512
be771a83
GS
2513(S) A warning peculiar to VMS. Perl keeps track of the number of times
2514you've called C<fork> and C<exec>, to determine whether the current call
2515to C<exec> should affect the current script or a subprocess (see
2516L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2517Perl is making a guess and treating this C<exec> as a request to
2518terminate the Perl script and execute the specified command.
748a9306 2519
870978ae
FC
2520=item internal %<num>p might conflict with future printf extensions
2521
2522(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2523formatting follows a slightly different set of rules when called from
2524C or XS code. Specifically, formats consisting of digits followed
2525by "p" (e.g., "%7p") are reserved for future use. If you see this
2526message, then an XS module tried to call that routine with one such
2527reserved format.
2528
e0e4a6e3 2529=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2530
fa816bf3 2531(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2532S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2533discovered.
a0d0e21e 2534
6df41af2
GS
2535=item %s (...) interpreted as function
2536
75b44862 2537(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2538followed by parentheses turns into a function, with all the list
64977eb6 2539operators arguments found inside the parentheses. See
13a2d996 2540L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2541
f51551f7
FC
2542=item In '(?...)', the '(' and '?' must be adjacent in regex;
2543marked by S<<-- HERE> in m/%s/
2544
2545(F) The two-character sequence C<"(?"> in this context in a regular
2546expression pattern should be an indivisible token, with nothing
2547intervening between the C<"("> and the C<"?">, but you separated them
2548with whitespace.
2549
09bef843
SB
2550=item Invalid %s attribute: %s
2551
a4a4c9e2 2552(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2553by Perl or by a user-supplied handler. See L<attributes>.
2554
2555=item Invalid %s attributes: %s
2556
a4a4c9e2 2557(F) The indicated attributes for a subroutine or variable were not
be771a83 2558recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2559
e0e4a6e3
FC
2560=item Invalid character in charnames alias definition; marked by
2561S<<-- HERE> in '%s
225fb84f
KW
2562
2563(F) You tried to create a custom alias for a character name, with
2564the C<:alias> option to C<use charnames> and the specified character in
2565the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2566
c8028aa6
TC
2567=item Invalid \0 character in %s for %s: %s\0%s
2568
fa3234e3
FC
2569(W syscalls) Embedded \0 characters in pathnames or other system call
2570arguments produce a warning as of 5.20. The parts after the \0 were
2571formerly ignored by system calls.
c8028aa6 2572
e0e4a6e3 2573=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2574
2575(F) Only certain characters are valid for character names. The
2576indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2577
c635e13b
PP
2578=item Invalid conversion in %s: "%s"
2579
be771a83
GS
2580(W printf) Perl does not understand the given format conversion. See
2581L<perlfunc/sprintf>.
c635e13b 2582
e0e4a6e3
FC
2583=item Invalid escape in the specified encoding in regex; marked by
2584S<<-- HERE> in m/%s/
9e08bc66 2585
98d31c73 2586(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2587didn't correspond to a single character through the conversion
2588from the encoding specified by the encoding pragma.
98d31c73
FC
2589The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2590instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2591The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2592escape was discovered.
2593
8149aa9f
FC
2594=item Invalid hexadecimal number in \N{U+...}
2595
e0e4a6e3
FC
2596=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2597S<<-- HERE> in m/%s/
aec0ef10 2598
8149aa9f 2599(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2600number. Either it is empty, or you tried to use a character other than
26010 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2602
6651ba0b
FC
2603=item Invalid module name %s with -%c option: contains single ':'
2604
2605(F) The module argument to perl's B<-m> and B<-M> command-line options
2606cannot contain single colons in the module name, but only in the
2607arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2608B<-MFoo:Bar=baz> is not.
2609
2c7d6b9c
RGS
2610=item Invalid mro name: '%s'
2611
162a3e34
FC
2612(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2613where C<foo> is not a valid method resolution order (MRO). Currently,
2614the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2615a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2616
40e4140b
FC
2617=item Invalid negative number (%s) in chr
2618
2619(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2620not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2621character (U+FFFD).
2622
6651ba0b
FC
2623=item invalid option -D%c, use -D'' to see choices
2624
8ff21bfe
FC
2625(S debugging) Perl was called with invalid debugger flags. Call perl
2626with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2627See also L<perlrun/-Dletters>.
6651ba0b 2628
e0e4a6e3 2629=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2630
2631(F) The range specified in a character class had a minimum character
7253e4e3
RK
2632greater than the maximum character. One possibility is that you forgot the
2633C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2634up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2635problem was discovered. See L<perlre>.
6df41af2 2636
d1573ac7 2637=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2638
2639(F) The range specified in the tr/// or y/// operator had a minimum
2640character greater than the maximum character. See L<perlop>.
2641
09bef843
SB
2642=item Invalid separator character %s in attribute list
2643
0120eecf 2644(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2645elements of an attribute list. If the previous attribute had a
2646parenthesised parameter list, perhaps that list was terminated too soon.
2647See L<attributes>.
09bef843 2648
b4581f09
JH
2649=item Invalid separator character %s in PerlIO layer specification %s
2650
2bfc5f71
FC
2651(W layer) When pushing layers onto the Perl I/O system, something other
2652than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2653If the previous attribute had a parenthesised parameter list, perhaps that
2654list was terminated too soon.
2655
2c86d456
DG
2656=item Invalid strict version format (%s)
2657
fa816bf3 2658(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2659A "strict" version number is a positive decimal number (integer or
2660decimal-fraction) without exponentiation or else a dotted-decimal
2661v-string with a leading 'v' character and at least three components.
a6485a24 2662The parenthesized text indicates which criteria were not met.
2c86d456
DG
2663See the L<version> module for more details on allowed version formats.
2664
49704364 2665=item Invalid type '%s' in %s
96e4d5b1 2666
49704364
LW
2667(F) The given character is not a valid pack or unpack type.
2668See L<perlfunc/pack>.
6728c851 2669
49704364 2670(W) The given character is not a valid pack or unpack type but used to be
75b44862 2671silently ignored.
96e4d5b1 2672
2c86d456
DG
2673=item Invalid version format (%s)
2674
fa816bf3 2675(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2676A "lax" version number is a positive decimal number (integer or
2677decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2678v-string. If the v-string has fewer than three components, it
2679must have a leading 'v' character. Otherwise, the leading 'v' is
2680optional. Both decimal and dotted-decimal versions may have a
2681trailing "alpha" component separated by an underscore character
2682after a fractional or dotted-decimal component. The parenthesized
2683text indicates which criteria were not met. See the L<version> module
2684for more details on allowed version formats.
46314c13 2685
798ae1b7
DG
2686=item Invalid version object
2687
fa816bf3
FC
2688(F) The internal structure of the version object was invalid.
2689Perhaps the internals were modified directly in some way or
2690an arbitrary reference was blessed into the "version" class.
798ae1b7 2691
cd209d9d 2692=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2693marked by S<<-- HERE> in m/%s/
675fa9ff 2694
cd209d9d 2695(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2696this context in a regular expression pattern should be an
2697indivisible token, with nothing intervening between the C<"(">
cd209d9d 2698and the C<"*">, but you separated them.
675fa9ff 2699
a0d0e21e
LW
2700=item ioctl is not implemented
2701
2702(F) Your machine apparently doesn't implement ioctl(), which is pretty
2703strange for a machine that supports C.
2704
c289d2f7
JH
2705=item ioctl() on unopened %s
2706
2707(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2708Check your control flow and number of arguments.
c289d2f7 2709
fe13d51d 2710=item IO layers (like '%s') unavailable
363c40c4
SB
2711
2712(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2713you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2714with 'useperlio'.
2715
80cbd5ad
JH
2716=item IO::Socket::atmark not implemented on this architecture
2717
2718(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2719neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2720
4f650b80 2721=item $* is no longer supported
b4581f09 2722
4f650b80 2723(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2724perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2725previous versions of perl the use of C<$*> enabled or disabled multi-line
2726matching within a string.
4fd19576
B
2727
2728Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2729modifiers. You can enable C</m> for a lexical scope (even a whole file)
2730with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2731then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2732
8ae1fe26
RGS
2733=item $# is no longer supported
2734
a58ac25e 2735(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2736perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2737should use the printf/sprintf functions instead.
8ae1fe26 2738
ccf3535a 2739=item '%s' is not a code reference
6ad11d81 2740
6903afa2
FC
2741(W overload) The second (fourth, sixth, ...) argument of
2742overload::constant needs to be a code reference. Either
2743an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2744
ccf3535a 2745=item '%s' is not an overloadable type
6ad11d81 2746
04a80ee0
RGS
2747(W overload) You tried to overload a constant type the overload package is
2748unaware of.
6ad11d81 2749
5a25739d
FC
2750=item -i used with no filenames on the command line, reading from STDIN
2751
2752(S inplace) The C<-i> option was passed on the command line, indicating
2753that the script is intended to edit files in place, but no files were
2754given. This is usually a mistake, since editing STDIN in place doesn't
2755make sense, and can be confusing because it can make perl look like
2756it is hanging when it is really just trying to read from STDIN. You
2757should either pass a filename to edit, or remove C<-i> from the command
2758line. See L<perlrun> for more details.
2759
aec0ef10 2760=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2761
2762(P) The regular expression parser is confused.
2763
0953b66b
FC
2764=item keys on reference is experimental
2765
0773cb3e
FC
2766(S experimental::autoderef) C<keys> with a scalar argument is experimental
2767and may change or be removed in a future Perl version. If you want to
2768take the risk of using this feature, simply disable this warning:
0953b66b 2769
d401967c 2770 no warnings "experimental::autoderef";
0953b66b 2771
a0d0e21e
LW
2772=item Label not found for "last %s"
2773
be771a83
GS
2774(F) You named a loop to break out of, but you're not currently in a loop
2775of that name, not even if you count where you were called from. See
2776L<perlfunc/last>.
a0d0e21e
LW
2777
2778=item Label not found for "next %s"
2779
2780(F) You named a loop to continue, but you're not currently in a loop of
2781that name, not even if you count where you were called from. See
2782L<perlfunc/last>.
2783
2784=item Label not found for "redo %s"
2785
2786(F) You named a loop to restart, but you're not currently in a loop of
2787that name, not even if you count where you were called from. See
2788L<perlfunc/last>.
2789
85ab1d1d 2790=item leaving effective %s failed
5ff3f7a4 2791
85ab1d1d 2792(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2793effective uids or gids failed.
2794
49704364
LW
2795=item length/code after end of string in unpack
2796
d7f8936a 2797(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2798length/code combination tried to obtain more data. This results in
2799an undefined value for the length. See L<perlfunc/pack>.
49704364 2800
25e26107 2801=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2802
0d46a4e7
FC
2803(W syntax) You used length() on either an array or a hash when you
2804probably wanted a count of the items.
e508c8a4
MH
2805
2806Array size can be obtained by doing:
2807
2808 scalar(@array);
2809
2810The number of items in a hash can be obtained by doing:
2811
2812 scalar(keys %hash);
2813
f0e67a1d
Z
2814=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2815
d4fe7078
RS
2816(F) An extension is attempting to insert text into the current parse
2817(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2818couldn't be part of the current input. This is an inherent pitfall
2819of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2820it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2821
2822=item Lexing code internal error (%s)
2823
2824(F) Lexing code supplied by an extension violated the lexer's API in a
2825detectable way.
2826
69282e91 2827=item listen() on closed socket %s
a0d0e21e 2828
be771a83
GS
2829(W closed) You tried to do a listen on a closed socket. Did you forget
2830to check the return value of your socket() call? See
2831L<perlfunc/listen>.
a0d0e21e 2832
6651ba0b
FC
2833=item List form of piped open not implemented
2834
2835(F) On some platforms, notably Windows, the three-or-more-arguments
2836form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2837Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2838
b35b96b6
JH
2839=item localtime(%f) failed
2840
2841(W overflow) You called C<localtime> with a number that it could not handle:
2842too large, too small, or NaN. The returned value is C<undef>.
2843
bcd05b94 2844=item localtime(%f) too large
8b56d6ff 2845
e9200be3 2846(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2847than it can reliably handle and C<localtime> probably returned the
6903afa2 2848wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2849not-a-number value).
2850
bcd05b94 2851=item localtime(%f) too small
fc003d4b 2852
e9200be3 2853(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2854than it can reliably handle and C<localtime> probably returned the
e7a1a147 2855wrong date.
8b56d6ff 2856
58e23c8d 2857=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2858
2859(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2860handle. This restriction may be eased in a future release.
2e50fd82 2861
b88df990
NC
2862=item Lost precision when %s %f by 1
2863
e63e8a91
FC
2864(W imprecision) The value you attempted to increment or decrement by one
2865is too large for the underlying floating point representation to store
2866accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2867warning because it has already switched from integers to floating point
2868when values are too large for integers, and now even floating point is
2869insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2870
93fad930 2871=item lstat() on filehandle%s
2f7da168
RK
2872
2873(W io) You tried to do an lstat on a filehandle. What did you mean
2874by that? lstat() makes sense only on filenames. (Perl did a fstat()
2875instead on the filehandle.)
2876
345d70e3 2877=item lvalue attribute %s already-defined subroutine
bb3abb05 2878
345d70e3
FC
2879(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2880attribute on or off on a Perl subroutine that is already defined
2881does not always work properly. It may or may not do what you
2882want, depending on what code is inside the subroutine, with exact
2883details subject to change between Perl versions. Only do this
2884if you really know what you are doing.
bb3abb05 2885
885ef6f5
GG
2886=item lvalue attribute ignored after the subroutine has been defined
2887
345d70e3
FC
2888(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2889subroutine an lvalue subroutine after it has been defined is
2890not permitted. To make the subroutine an lvalue subroutine,
2891add the lvalue attribute to the definition, or put the C<sub
2892foo :lvalue;> declaration before the definition.
2893
2894See also L<attributes.pm|attributes>.
885ef6f5 2895
6f1b3ab0
FC
2896=item Magical list constants are not supported
2897
2898(F) You assigned a magical array to a stash element, and then tried
2899to use the subroutine from the same slot. You are asking Perl to do
2900something it cannot do, details subject to change between Perl versions.
2901
2db62bbc 2902=item Malformed integer in [] in pack
49704364 2903
2db62bbc 2904(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2905are permitted. See L<perlfunc/pack>.
2906
2907=item Malformed integer in [] in unpack
2908
2db62bbc 2909(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2910are permitted. See L<perlfunc/pack>.
2911
6df41af2
GS
2912=item Malformed PERLLIB_PREFIX
2913
2914(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2915
2916 prefix1;prefix2
2917
2918or
6df41af2
GS
2919 prefix1 prefix2
2920
be771a83
GS
2921with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2922a builtin library search path, prefix2 is substituted. The error may
2923appear if components are not found, or are too long. See
fecfaeb8 2924"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2925
2f758a16
ST
2926=item Malformed prototype for %s: %s
2927
d37a9538
ST
2928(F) You tried to use a function with a malformed prototype. The
2929syntax of function prototypes is given a brief compile-time check for
2930obvious errors like invalid characters. A more rigorous check is run
2931when the function is called.
30d9c59b
Z
2932Perhaps the function's author was trying to write a subroutine signature
2933but didn't enable that feature first (C<use feature 'signatures'>),
2934so the signature was instead interpreted as a bad prototype.
2f758a16 2935
ba210ebe
JH
2936=item Malformed UTF-8 character (%s)
2937
4d6f11e5 2938(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2939encoding rules, even though it had the UTF8 flag on.
ba210ebe 2940
2575c402
JW
2941One possible cause is that you set the UTF8 flag yourself for data that
2942you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 29438-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2944
2945If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2946sequences are handled gracefully, but if you use C<:utf8>, the flag is
2947set without validating the data, possibly resulting in this error
2948message.
2949
2950See also L<Encode/"Handling Malformed Data">.
901b21bf 2951
107160e2
KW
2952=item Malformed UTF-8 character immediately after '%s'
2953
2954(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2955encoding rules. The message prints out the properly encoded characters
2956just before the first bad one. If C<utf8> warnings are enabled, a
2957warning is generated that gives more details about the type of
2958malformation.
2959
bde9e88d 2960=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2961
2962(F) The charnames handler returned malformed UTF-8.
2963
4a5d3a93
FC
2964=item Malformed UTF-8 string in '%c' format in unpack
2965
2966(F) You tried to unpack something that didn't comply with UTF-8 encoding
2967rules and perl was unable to guess how to make more progress.
2968
f337b084
TH
2969=item Malformed UTF-8 string in pack
2970
2971(F) You tried to pack something that didn't comply with UTF-8 encoding
2972rules and perl was unable to guess how to make more progress.
2973
2974=item Malformed UTF-8 string in unpack
2975
2976(F) You tried to unpack something that didn't comply with UTF-8 encoding
2977rules and perl was unable to guess how to make more progress.
2978
4a5d3a93 2979=item Malformed UTF-16 surrogate
f337b084 2980
4a5d3a93
FC
2981(F) Perl thought it was reading UTF-16 encoded character data but while
2982doing it Perl met a malformed Unicode surrogate.
2983
30d9c59b
Z
2984=item Mandatory parameter follows optional parameter
2985
2986(F) In a subroutine signature, you wrote something like "$a = undef,
2987$b", making an earlier parameter optional and a later one mandatory.
2988Parameters are filled from left to right, so it's impossible for the
2989caller to omit an earlier one and pass a later one. If you want to act
2990as if the parameters are filled from right to left, declare the rightmost
2991optional and then shuffle the parameters around in the subroutine's body.
2992
2d88a86a
KW
2993=item Matched non-Unicode code point 0x%X against Unicode property; may
2994not be portable
2995
2996(S non_unicode) Perl allows strings to contain a superset of
2997Unicode code points; each code point may be as large as what is storable
2998in an unsigned integer on your system, but these may not be accepted by
2999other languages/systems. This message occurs when you matched a string
3000containing such a code point against a regular expression pattern, and
3001the code point was matched against a Unicode property, C<\p{...}> or
3002C<\P{...}>. Unicode properties are only defined on Unicode code points,
3003so the result of this match is undefined by Unicode, but Perl (starting
3004in v5.20) treats non-Unicode code points as if they were typical
3005unassigned Unicode ones, and matched this one accordingly. Whether a
3006given property matches these code points or not is specified in
3007L<perluniprops/Properties accessible through \p{} and \P{}>.
3008
3009This message is suppressed (unless it has been made fatal) if it is
3010immaterial to the results of the match if the code point is Unicode or
3011not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3012the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3013Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3014every code point except these 22.)
3015
3016Getting this message indicates that the outcome of the match arguably
3017should have been the opposite of what actually happened. If you think
3018that is the case, you may wish to make the C<non_unicode> warnings
3019category fatal; if you agree with Perl's decision, you may wish to turn
3020off this category.
3021
3022See L<perlunicode/Beyond Unicode code points> for more information.
3023
e0e4a6e3
FC
3024=item %s matches null string many times in regex; marked by S<<-- HERE> in
3025m/%s/
4a5d3a93
FC
3026
3027(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3028regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3029shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3030See L<perlre>.
f337b084 3031
de42a5a9 3032=item Maximal count of pending signals (%u) exceeded
2563cec5 3033
6903afa2 3034(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3035usually indicates that your operating system tried to deliver signals
3036too fast (with a very high priority), starving the perl process from
3037resources it would need to reach a point where it can process signals
6903afa2 3038safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3039
25f58aea
PN
3040=item "%s" may clash with future reserved word
3041
3042(W) This warning may be due to running a perl5 script through a perl4
3043interpreter, especially if the word that is being warned about is
3044"use" or "my".
3045
0d2487cd 3046=item '%' may not be used in pack
6df41af2
GS
3047
3048(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3049checksumming process loses information, and you can't go the other way.
3050See L<perlfunc/unpack>.
6df41af2 3051
a0d0e21e
LW
3052=item Method for operation %s not found in package %s during blessing
3053
3054(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3055doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3056
3cdd684c
TP
3057=item Method %s not permitted
3058
3059See Server error.
3060
a0d0e21e
LW
3061=item Might be a runaway multi-line %s string starting on line %d
3062
3063(S) An advisory indicating that the previous error may have been caused
3064by a missing delimiter on a string or pattern, because it eventually
3065ended earlier on the current line.
3066
3067=item Misplaced _ in number
3068
d4ced10d
JH
3069(W syntax) An underscore (underbar) in a numeric constant did not
3070separate two digits.
a0d0e21e 3071
7baa4690
HS
3072=item Missing argument in %s
3073
3664866e
AB
3074(W missing) You called a function with fewer arguments than other
3075arguments you supplied indicated would be needed.
3076
3077Currently only emitted when a printf-type format required more
3078arguments than were supplied, but might be used in the future for
3079other cases where we can statically determine that arguments to
3080functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3081
9e81e6a1
RGS
3082=item Missing argument to -%c
3083
3084(F) The argument to the indicated command line switch must follow
3085immediately after the switch, without intervening spaces.
3086
ff3f963a 3087=item Missing braces on \N{}
423cee85 3088
e0e4a6e3 3089=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3090
4a2d328f 3091(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3092double-quotish context. This can also happen when there is a space
3093(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3094This modifier does not change the requirement that the brace immediately
3095follow the C<\N>.
423cee85 3096
f0a2b745
KW
3097=item Missing braces on \o{}
3098
3099(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3100
a0d0e21e
LW
3101=item Missing comma after first argument to %s function
3102
3103(F) While certain functions allow you to specify a filehandle or an
3104"indirect object" before the argument list, this ain't one of them.
3105
06eaf0bc
GS
3106=item Missing command in piped open
3107
be771a83
GS
3108(W pipe) You used the C<open(FH, "| command")> or
3109C<open(FH, "command |")> construction, but the command was missing or
3110blank.
06eaf0bc 3111
961ce445
RGS
3112=item Missing control char name in \c
3113
3114(F) A double-quoted string ended with "\c", without the required control
3115character name.
3116
591f5ca2
FC
3117=item Missing ']' in prototype for %s : %s
3118
bfe11873 3119(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3120
8767b1ab 3121=item Missing name in "%s sub"
6df41af2 3122
87444db5 3123(F) The syntax for lexically scoped subroutines requires that
be771a83 3124they have a name with which they can be found.
6df41af2
GS
3125
3126=item Missing $ on loop variable
3127
be771a83
GS
3128(F) Apparently you've been programming in B<csh> too much. Variables
3129are always mentioned with the $ in Perl, unlike in the shells, where it
3130can vary from one line to the next.
6df41af2 3131
cc507455 3132=item (Missing operator before %s?)
748a9306 3133
56da5a46
RGS
3134(S syntax) This is an educated guess made in conjunction with the message
3135"%s found where operator expected". Often the missing operator is a comma.
748a9306 3136
f51551f7
FC
3137=item Missing or undefined argument to require
3138
3139(F) You tried to call require with no argument or with an undefined
3140value as an argument. Require expects either a package name or a
3141file-specification as an argument. See L<perlfunc/require>.
3142
e0e4a6e3 3143=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3144
ff3f963a
KW
3145(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3146
4a68bf9d 3147=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3148
d32207c9
FC
3149(F) C<\N> has two meanings.
3150
3151The traditional one has it followed by a name enclosed in braces,
3152meaning the character (or sequence of characters) given by that
fa816bf3 3153name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3154double-quoted strings and regular expression patterns. In patterns,
3155it doesn't have the meaning an unescaped C<*> does.
3156
3157Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3158in patterns, namely to match a non-newline character. (This is short
3159for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3160
3161This can lead to some ambiguities. When C<\N> is not followed immediately
3162by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3163form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3164means to match the given quantity of non-newlines (in these examples,
31653; and 5 or more, respectively). In all other case, where there is a
3166C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3167
3168However, if there is no matching C<}>, Perl doesn't know if it was
3169mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3170If you meant the former, add the right brace; if you meant the latter,
3171escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3172
d98d5fff 3173=item Missing right curly or square bracket
a0d0e21e 3174
be771a83
GS
3175(F) The lexer counted more opening curly or square brackets than closing
3176ones. As a general rule, you'll find it's missing near the place you
3177were last editing.
a0d0e21e 3178
6df41af2
GS
3179=item (Missing semicolon on previous line?)
3180
56da5a46
RGS
3181(S syntax) This is an educated guess made in conjunction with the message
3182"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3183the previous line just because you saw this message.
3184
a0d0e21e
LW
3185=item Modification of a read-only value attempted
3186
3187(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3188constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3189catches that. But an easy way to do the same thing is:
3190
3191 sub mod { $_[0] = 1 }
3192 mod(2);
3193
3194Another way is to assign to a substr() that's off the end of the string.
3195
c5674021
PDF
3196Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3197is aliased to a constant in the look I<LIST>:
3198
b7e4ecc1
FC
3199 $x = 1;
3200 foreach my $n ($x, 2) {
3201 $n *= 2; # modifies the $x, but fails on attempt to
3202 } # modify the 2
c5674021 3203
7a4340ed 3204=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3205
3206(F) You tried to make an array value spring into existence, and the
3207subscript was probably negative, even counting from end of the array
3208backwards.
3209
7a4340ed 3210=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3211
be771a83
GS
3212(P) You tried to make a hash value spring into existence, and it
3213couldn't be created for some peculiar reason.
a0d0e21e
LW
3214
3215=item Module name must be constant
3216
3217(F) Only a bare module name is allowed as the first argument to a "use".
3218
be98fb35 3219=item Module name required with -%c option
6df41af2 3220
be98fb35
GS
3221(F) The C<-M> or C<-m> options say that Perl should load some module, but
3222you omitted the name of the module. Consult L<perlrun> for full details
3223about C<-M> and C<-m>.
6df41af2 3224
fe13d51d 3225=item More than one argument to '%s' open
ed9aa3b7 3226
6903afa2 3227(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3228can happen if you are trying to open a pipe to a command that takes a
3229list of arguments, but have forgotten to specify a piped open mode.
3230See L<perlfunc/open> for details.
3231
85396b18
FC
3232=item mprotect for COW string %p %u failed with %d
3233
3234(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3235L<perlguts/"Copy on Write">), but a shared string buffer
3236could not be made read-only.
3237
92951bce
FC
3238=item mprotect for %p %u failed with %d
3239
85396b18
FC
3240(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3241but an op tree could not be made read-only.
3242
3243=item mprotect RW for COW string %p %u failed with %d
3244
3245(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3246L<perlguts/"Copy on Write">), but a read-only shared string
3247buffer could not be made mutable.
3248
92951bce
FC
3249=item mprotect RW for %p %u failed with %d
3250
3251(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3252L<perlhacktips>), but a read-only op tree could not be made
3253mutable before freeing the ops.
92951bce 3254
a0d0e21e
LW
3255=item msg%s not implemented
3256
3257(F) You don't have System V message IPC on your system.
3258
3259=item Multidimensional syntax %s not supported
3260
75b44862
GS
3261(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3262They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3263
49704364 3264=item '/' must follow a numeric type in unpack
6df41af2 3265
49704364
LW
3266(F) You had an unpack template that contained a '/', but this did not
3267follow some unpack specification producing a numeric value.
3268See L<perlfunc/pack>.
6df41af2
GS
3269
3270=item "my sub" not yet implemented
3271
be771a83
GS
3272(F) Lexically scoped subroutines are not yet implemented. Don't try
3273that yet.
6df41af2 3274
5a25739d
FC
3275=item "my %s" used in sort comparison
3276
3277(W syntax) The package variables $a and $b are used for sort comparisons.
3278You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3279sort comparison block, and the variable had earlier been declared as a
3280lexical variable. Either qualify the sort variable with the package
3281name, or rename the lexical variable.
3282
fd1b7234 3283=item "my" variable %s can't be in a package
6df41af2 3284
be771a83
GS
3285(F) Lexically scoped variables aren't in a package, so it doesn't make
3286sense to try to declare one with a package qualifier on the front. Use
3287local() if you want to localize a package variable.
09bef843 3288
8149aa9f
FC
3289=item Name "%s::%s" used only once: possible typo
3290
c59aba6c
FC
3291(W once) Typographical errors often show up as unique variable
3292names. If you had a good reason for having a unique name, then
3293just mention it again somehow to suppress the message. The C<our>
08a33b6b 3294declaration is also provided for this purpose.
c59aba6c 3295
66a1f5ec
FC
3296NOTE: This warning detects package symbols that have been used
3297only once. This means lexical variables will never trigger this
3298warning. It also means that all of the package variables $c, @c,
3299%c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3300format) are considered the same; if a program uses $c only once
3301but also uses any of the others it will not trigger this warning.
3302Symbols beginning with an underscore and symbols using special
3303identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3304
e0e4a6e3 3305=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3306
3307(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3308exactly 3 digits long. This helps catch some ambiguities. If your
3309constant is too short, add leading zeros, like
3310
3311 (?[ [ \078 ] ]) # Syntax error!
3312 (?[ [ \0078 ] ]) # Works
3313 (?[ [ \007 8 ] ]) # Clearer
3314
3315The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3316