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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
de42a5a9 53=item Allocation too large: %x
a0d0e21e 54
6df41af2 55(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 56
04f74579 57=item '%c' allowed only after types %s in %s
ef54e1a4 58
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59(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
60after certain types. See L<perlfunc/pack>.
ef54e1a4 61
6df41af2 62=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 63
75b44862 64(W ambiguous) A subroutine you have declared has the same name as a Perl
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65keyword, and you have used the name without qualification for calling
66one or the other. Perl decided to call the builtin because the
67subroutine is not imported.
43192e07 68
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69To force interpretation as a subroutine call, either put an ampersand
70before the subroutine name, or qualify the name with its package.
71Alternatively, you can import the subroutine (or pretend that it's
72imported with the C<use subs> pragma).
43192e07 73
6df41af2 74To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 75on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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76to be an object method (see L<perlsub/"Subroutine Attributes"> or
77L<attributes>).
43192e07 78
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79=item Ambiguous range in transliteration operator
80
81(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
82all. To include a C<-> character in a transliteration, put it either
83first or last. (In the past, C<tr/a-z-0//> was synonymous with
84C<tr/a-y//>, which was probably not what you would have expected.)
85
6df41af2 86=item Ambiguous use of %s resolved as %s
43192e07 87
7c7af292 88(S ambiguous) You said something that may not be interpreted the way
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89you thought. Normally it's pretty easy to disambiguate it by supplying
90a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 91
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92=item Ambiguous use of -%s resolved as -&%s()
93
94(S ambiguous) You wrote something like C<-foo>, which might be the
95string C<"-foo">, or a call to the function C<foo>, negated. If you meant
96the string, just write C<"-foo">. If you meant the function call,
97write C<-foo()>.
98
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99=item Ambiguous use of %c resolved as operator %c
100
7c7af292 101(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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102bitwise and, and multiplication) I<and> initial special characters
103(denoting hashes, subroutines and typeglobs), and you said something
104like C<*foo * foo> that might be interpreted as either of them. We
105assumed you meant the infix operator, but please try to make it more
106clear -- in the example given, you might write C<*foo * foo()> if you
107really meant to multiply a glob by the result of calling a function.
d8225693 108
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109=item Ambiguous use of %c{%s} resolved to %c%s
110
111(W ambiguous) You wrote something like C<@{foo}>, which might be
112asking for the variable C<@foo>, or it might be calling a function
113named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 114the variable, you can just write C<@foo>. If you wanted to call the
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115function, write C<@{foo()}> ... or you could just not have a variable
116and a function with the same name, and save yourself a lot of trouble.
117
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118=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
119
120=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 121
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122(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
123the name of a Perl keyword), which might be looking for element number
1242 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
125might have meant to pass an anonymous arrayref to the function named
126foo, and then do a scalar deref on the value it returns. If you meant
127that, write C<${foo([2])}>.
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128
129In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
130to disambiguate between array subscripts and character classes.
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131C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
132by the character class C<[2345]>. If an array subscript is what you
133want, you can avoid the warning by changing C</${length[2345]}/> to the
134unsightly C</${\$length[2345]}/>, by renaming your array to something
135that does not coincide with a built-in keyword, or by simply turning
136off warnings with C<no warnings 'ambiguous';>.
4da60377 137
6df41af2 138=item '|' and '<' may not both be specified on command line
a0d0e21e 139
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140(F) An error peculiar to VMS. Perl does its own command line
141redirection, and found that STDIN was a pipe, and that you also tried to
142redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 143
6df41af2 144=item '|' and '>' may not both be specified on command line
1028017a 145
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146(F) An error peculiar to VMS. Perl does its own command line
147redirection, and thinks you tried to redirect stdout both to a file and
148into a pipe to another command. You need to choose one or the other,
149though nothing's stopping you from piping into a program or Perl script
150which 'splits' output into two streams, such as
1028017a 151
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152 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
153 while (<STDIN>) {
154 print;
155 print OUT;
156 }
157 close OUT;
c9f97d15 158
6df41af2 159=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 160
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161(W misc) The pattern match (C<//>), substitution (C<s///>), and
162transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 163one of them to an array or a hash, it will convert the array or hash to
ac036724 164a scalar value (the length of an array, or the population info of a
165hash) and then work on that scalar value. This is probably not what
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166you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
167alternatives.
eb6e2d6f 168
6df41af2 169=item Arg too short for msgsnd
76cd736e 170
6df41af2 171(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 172
f86702cc 173=item Argument "%s" isn't numeric%s
a0d0e21e 174
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175(W numeric) The indicated string was fed as an argument to an operator
176that expected a numeric value instead. If you're fortunate the message
177will identify which operator was so unfortunate.
a0d0e21e 178
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179=item Argument list not closed for PerlIO layer "%s"
180
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181(W layer) When pushing a layer with arguments onto the Perl I/O
182system you forgot the ) that closes the argument list. (Layers
183take care of transforming data between external and internal
184representations.) Perl stopped parsing the layer list at this
185point and did not attempt to push this layer. If your program
186didn't explicitly request the failing operation, it may be the
187result of the value of the environment variable PERLIO.
b4581f09 188
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189=item Argument "%s" treated as 0 in increment (++)
190
191(W numeric) The indicated string was fed as an argument to the C<++>
192operator which expects either a number or a string matching
193C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
194Auto-decrement> for details.
195
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196=item assertion botched: %s
197
21b5e840 198(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 199
0eacef8e 200=item Assertion %s failed: file "%s", line %d
a0d0e21e 201
21b5e840 202(X) A general assertion failed. The file in question must be examined.
a0d0e21e 203
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204=item Assigning non-zero to $[ is no longer possible
205
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206(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
207the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 208
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209=item Assignment to both a list and a scalar
210
211(F) If you assign to a conditional operator, the 2nd and 3rd arguments
212must either both be scalars or both be lists. Otherwise Perl won't
213know which context to supply to the right side.
214
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215=item <> at require-statement should be quotes
216
217(F) You wrote C<< require <file> >> when you should have written
218C<require 'file'>.
219
2393f1b9 220=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 221
49293501 222(F) The failing code has attempted to get or set a key which is not in
2393f1b9 223the current set of allowed keys of a restricted hash.
49293501 224
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225=item Attempt to bless into a freed package
226
227(F) You wrote C<bless $foo> with one argument after somehow causing
228the current package to be freed. Perl cannot figure out what to
229do, so it throws up in hands in despair.
230
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231=item Attempt to bless into a reference
232
233(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 234the name of the package to bless the resulting object into. You've
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235supplied instead a reference to something: perhaps you wrote
236
237 bless $self, $proto;
238
239when you intended
240
241 bless $self, ref($proto) || $proto;
242
243If you actually want to bless into the stringified version
244of the reference supplied, you need to stringify it yourself, for
245example by:
246
247 bless $self, "$proto";
248
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249=item Attempt to clear deleted array
250
251(S debugging) An array was assigned to when it was being freed.
252Freed values are not supposed to be visible to Perl code. This
253can also happen if XS code calls C<av_clear> from a custom magic
254callback on the array.
255
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256=item Attempt to delete disallowed key '%s' from a restricted hash
257
258(F) The failing code attempted to delete from a restricted hash a key
259which is not in its key set.
260
261=item Attempt to delete readonly key '%s' from a restricted hash
262
263(F) The failing code attempted to delete a key whose value has been
264declared readonly from a restricted hash.
265
de42a5a9 266=item Attempt to free non-arena SV: 0x%x
a0d0e21e 267
f84fe999 268(S internal) All SV objects are supposed to be allocated from arenas
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269that will be garbage collected on exit. An SV was discovered to be
270outside any of those arenas.
a0d0e21e 271
12578ffb 272=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 273
f84fe999 274(S internal) Perl maintains a reference-counted internal table of
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275strings to optimize the storage and access of hash keys and other
276strings. This indicates someone tried to decrement the reference count
277of a string that can no longer be found in the table.
bbce6d69 278
7d5b40b4 279=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 280
f84fe999 281(S debugging) Mortalized values are supposed to be freed by the
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282free_tmps() routine. This indicates that something else is freeing the
283SV before the free_tmps() routine gets a chance, which means that the
284free_tmps() routine will be freeing an unreferenced scalar when it does
285try to free it.
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286
287=item Attempt to free unreferenced glob pointers
288
f84fe999 289(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 290
7d5b40b4 291=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 292
8f7e4d2c 293(S internal) Perl went to decrement the reference count of a scalar to
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294see if it would go to 0, and discovered that it had already gone to 0
295earlier, and should have been freed, and in fact, probably was freed.
296This could indicate that SvREFCNT_dec() was called too many times, or
297that SvREFCNT_inc() was called too few times, or that the SV was
298mortalized when it shouldn't have been, or that memory has been
299corrupted.
a0d0e21e 300
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301=item Attempt to pack pointer to temporary value
302
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303(W pack) You tried to pass a temporary value (like the result of a
304function, or a computed expression) to the "p" pack() template. This
305means the result contains a pointer to a location that could become
306invalid anytime, even before the end of the current statement. Use
307literals or global values as arguments to the "p" pack() template to
308avoid this warning.
84902520 309
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310=item Attempt to reload %s aborted.
311
312(F) You tried to load a file with C<use> or C<require> that failed to
313compile once already. Perl will not try to compile this file again
314unless you delete its entry from %INC. See L<perlfunc/require> and
315L<perlvar/%INC>.
316
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317=item Attempt to set length of freed array
318
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319(W misc) You tried to set the length of an array which has
320been freed. You can do this by storing a reference to the
321scalar representing the last index of an array and later
322assigning through that reference. For example
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323
324 $r = do {my @a; \$#a};
325 $$r = 503
326
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327=item Attempt to use reference as lvalue in substr
328
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329(W substr) You supplied a reference as the first argument to substr()
330used as an lvalue, which is pretty strange. Perhaps you forgot to
331dereference it first. See L<perlfunc/substr>.
b7a902f4 332
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333=item Attribute "locked" is deprecated
334
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335(D deprecated) You have used the attributes pragma to modify the
336"locked" attribute on a code reference. The :locked attribute is
337obsolete, has had no effect since 5005 threads were removed, and
338will be removed in a future release of Perl 5.
c32124fe 339
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340=item Attribute prototype(%s) discards earlier prototype attribute in same sub
341
342(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
343example. Since each sub can only have one prototype, the earlier
344declaration(s) are discarded while the last one is applied.
345
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346=item Attribute "unique" is deprecated
347
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348(D deprecated) You have used the attributes pragma to modify
349the "unique" attribute on an array, hash or scalar reference.
350The :unique attribute has had no effect since Perl 5.8.8, and
351will be removed in a future release of Perl 5.
f1a3ce43 352
ccce04a4
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353=item av_reify called on tied array
354
355(S debugging) This indicates that something went wrong and Perl got I<very>
356confused about C<@_> or C<@DB::args> being tied.
357
de42a5a9 358=item Bad arg length for %s, is %u, should be %d
a0d0e21e 359
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360(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
361or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 362S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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363S<sizeof(struct shmid_ds *)>.
364
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365=item Bad evalled substitution pattern
366
496a33f5 367(F) You've used the C</e> switch to evaluate the replacement for a
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368substitution, but perl found a syntax error in the code to evaluate,
369most likely an unexpected right brace '}'.
370
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371=item Bad filehandle: %s
372
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373(F) A symbol was passed to something wanting a filehandle, but the
374symbol has no filehandle associated with it. Perhaps you didn't do an
375open(), or did it in another package.
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376
377=item Bad free() ignored
378
be771a83 379(S malloc) An internal routine called free() on something that had never
fa816bf3 380been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 381setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 382
9ea8bc6d 383This message can be seen quite often with DB_File on systems with "hard"
6903afa2 384dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 385which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 386
aa689395
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387=item Bad hash
388
389(P) One of the internal hash routines was passed a null HV pointer.
390
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391=item Badly placed ()'s
392
393(A) You've accidentally run your script through B<csh> instead
394of Perl. Check the #! line, or manually feed your script into
395Perl yourself.
396
a7cb8dae 397=item Bad name after %s
a0d0e21e 398
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399(F) You started to name a symbol by using a package prefix, and then
400didn't finish the symbol. In particular, you can't interpolate outside
401of quotes, so
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402
403 $var = 'myvar';
404 $sym = mypack::$var;
405
406is not the same as
407
408 $var = 'myvar';
409 $sym = "mypack::$var";
410
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411=item Bad plugin affecting keyword '%s'
412
413(F) An extension using the keyword plugin mechanism violated the
414plugin API.
415
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416=item Bad realloc() ignored
417
6903afa2
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418(S malloc) An internal routine called realloc() on something that
419had never been malloc()ed in the first place. Mandatory, but can
420be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 421
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422=item Bad symbol for array
423
424(P) An internal request asked to add an array entry to something that
425wasn't a symbol table entry.
426
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427=item Bad symbol for dirhandle
428
429(P) An internal request asked to add a dirhandle entry to something
430that wasn't a symbol table entry.
431
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432=item Bad symbol for filehandle
433
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434(P) An internal request asked to add a filehandle entry to something
435that wasn't a symbol table entry.
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436
437=item Bad symbol for hash
438
439(P) An internal request asked to add a hash entry to something that
440wasn't a symbol table entry.
441
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442=item Bareword found in conditional
443
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444(W bareword) The compiler found a bareword where it expected a
445conditional, which often indicates that an || or && was parsed as part
446of the last argument of the previous construct, for example:
34d09196
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447
448 open FOO || die;
449
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450It may also indicate a misspelled constant that has been interpreted as
451a bareword:
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?
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463
464=item Bareword "%s" refers to nonexistent package
465
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466(W bareword) You used a qualified bareword of the form C<Foo::>, but the
467compiler saw no other uses of that namespace before that point. Perhaps
468you need to predeclare a package?
6df41af2 469
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470=item BEGIN failed--compilation aborted
471
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472(F) An untrapped exception was raised while executing a BEGIN
473subroutine. Compilation stops immediately and the interpreter is
474exited.
a0d0e21e 475
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476=item BEGIN not safe after errors--compilation aborted
477
478(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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479implies a C<BEGIN {}>) after one or more compilation errors had already
480occurred. Since the intended environment for the C<BEGIN {}> could not
481be guaranteed (due to the errors), and since subsequent code likely
482depends on its correct operation, Perl just gave up.
68dc0745 483
c782d7ee 484=item \%d better written as $%d
6df41af2 485
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486(W syntax) Outside of patterns, backreferences live on as variables.
487The use of backslashes is grandfathered on the right-hand side of a
488substitution, but stylistically it's better to use the variable form
489because other Perl programmers will expect it, and it works better if
490there are more than 9 backreferences.
6df41af2 491
252aa082
JH
492=item Binary number > 0b11111111111111111111111111111111 non-portable
493
e476b1b5 494(W portable) The binary number you specified is larger than 2**32-1
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JH
495(4294967295) and therefore non-portable between systems. See
496L<perlport> for more on portability concerns.
252aa082 497
69282e91 498=item bind() on closed socket %s
a0d0e21e 499
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500(W closed) You tried to do a bind on a closed socket. Did you forget to
501check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 502
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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
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522=item Buffer overflow in prime_env_iter: %s
523
be771a83
GS
524(W internal) A warning peculiar to VMS. While Perl was preparing to
525iterate over %ENV, it encountered a logical name or symbol definition
526which was too long, so it was truncated to the string shown.
f675dbe5 527
a0d0e21e
LW
528=item Callback called exit
529
4929bf7b 530(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
531exited by calling exit.
532
6df41af2 533=item %s() called too early to check prototype
f675dbe5 534
be771a83
GS
535(W prototype) You've called a function that has a prototype before the
536parser saw a definition or declaration for it, and Perl could not check
537that the call conforms to the prototype. You need to either add an
538early prototype declaration for the subroutine in question, or move the
539subroutine definition ahead of the call to get proper prototype
540checking. Alternatively, if you are certain that you're calling the
541function correctly, you may put an ampersand before the name to avoid
542the warning. See L<perlsub>.
f675dbe5 543
56feebad
FC
544=item Calling POSIX::%s() is deprecated
545
546(D deprecated) You called a function whose use is deprecated. See
547the function's name in L<POSIX> for details.
548
49704364 549=item Cannot compress integer in pack
0258719b
NC
550
551(F) An argument to pack("w",...) was too large to compress. The BER
552compressed integer format can only be used with positive integers, and you
553attempted to compress Infinity or a very large number (> 1e308).
554See L<perlfunc/pack>.
555
49704364 556=item Cannot compress negative numbers in pack
0258719b
NC
557
558(F) An argument to pack("w",...) was negative. The BER compressed integer
559format can only be used with positive integers. See L<perlfunc/pack>.
560
5c1f4d79
NC
561=item Cannot convert a reference to %s to typeglob
562
6903afa2
FC
563(F) You manipulated Perl's symbol table directly, stored a reference
564in it, then tried to access that symbol via conventional Perl syntax.
565The access triggers Perl to autovivify that typeglob, but it there is
566no legal conversion from that type of reference to a typeglob.
5c1f4d79 567
4040665a 568=item Cannot copy to %s
ba2fdce6
NC
569
570(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 571be directly assigned to.
ba2fdce6 572
b5d97229
RGS
573=item Cannot find encoding "%s"
574
575(S io) You tried to apply an encoding that did not exist to a filehandle,
576either with open() or binmode().
577
7355df7e
FC
578=item Cannot set tied @DB::args
579
580(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
581is not supported. (Before this error was added, it used to crash.)
582
ce65bc73
FC
583=item Cannot tie unreifiable array
584
585(P) You somehow managed to call C<tie> on an array that does not
586keep a reference count on its arguments and cannot be made to
587do so. Such arrays are not even supposed to be accessible to
588Perl code, but are only used internally.
589
96ebfdd7
RK
590=item Can only compress unsigned integers in pack
591
592(F) An argument to pack("w",...) was not an integer. The BER compressed
593integer format can only be used with positive integers, and you attempted
594to compress something else. See L<perlfunc/pack>.
595
a0d0e21e
LW
596=item Can't bless non-reference value
597
598(F) Only hard references may be blessed. This is how Perl "enforces"
599encapsulation of objects. See L<perlobj>.
600
dc57907a
RGS
601=item Can't "break" in a loop topicalizer
602
0d863452 603(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 604a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
605
606=item Can't "break" outside a given block
dc57907a 607
0d863452
RH
608(F) You called C<break>, but you're not inside a C<given> block.
609
6df41af2
GS
610=item Can't call method "%s" on an undefined value
611
612(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
613object reference or package name contains an undefined value. Something
614like this will reproduce the error:
6df41af2
GS
615
616 $BADREF = undef;
617 process $BADREF 1,2,3;
618 $BADREF->process(1,2,3);
619
a0d0e21e
LW
620=item Can't call method "%s" on unblessed reference
621
54310121 622(F) A method call must know in what package it's supposed to run. It
be771a83
GS
623ordinarily finds this out from the object reference you supply, but you
624didn't supply an object reference in this case. A reference isn't an
625object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
626
627=item Can't call method "%s" without a package or object reference
628
629(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
630object reference or package name contains an expression that returns a
631defined value which is neither an object reference nor a package name.
72b5445b
GS
632Something like this will reproduce the error:
633
634 $BADREF = 42;
635 process $BADREF 1,2,3;
636 $BADREF->process(1,2,3);
637
dfe378f1
FC
638=item Can't call mro_isa_changed_in() on anonymous symbol table
639
640(P) Perl got confused as to whether a hash was a plain hash or a
641symbol table hash when trying to update @ISA caches.
642
2bf7e7b2
FC
643=item Can't call mro_method_changed_in() on anonymous symbol table
644
645(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
646not attached to the symbol table.
647
a0d0e21e
LW
648=item Can't chdir to %s
649
f703fc96 650(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
651that you can chdir to, possibly because it doesn't exist.
652
0545a864 653=item Can't check filesystem of script "%s" for nosuid
104d25b7 654
be771a83
GS
655(P) For some reason you can't check the filesystem of the script for
656nosuid.
104d25b7 657
22e74366 658=item Can't coerce %s to %s in %s
a0d0e21e
LW
659
660(F) Certain types of SVs, in particular real symbol table entries
55497cff 661(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
662say things like:
663
664 *foo += 1;
665
666You CAN say
667
668 $foo = *foo;
669 $foo += 1;
670
671but then $foo no longer contains a glob.
672
0d863452 673=item Can't "continue" outside a when block
dc57907a 674
0d863452
RH
675(F) You called C<continue>, but you're not inside a C<when>
676or C<default> block.
677
a0d0e21e
LW
678=item Can't create pipe mailbox
679
be771a83
GS
680(P) An error peculiar to VMS. The process is suffering from exhausted
681quotas or other plumbing problems.
a0d0e21e 682
eb64745e
GS
683=item Can't declare %s in "%s"
684
30c282f6
NC
685(F) Only scalar, array, and hash variables may be declared as "my", "our" or
686"state" variables. They must have ordinary identifiers as names.
a0d0e21e 687
fc7debfb
FC
688=item Can't "default" outside a topicalizer
689
690(F) You have used a C<default> block that is neither inside a
691C<foreach> loop nor a C<given> block. (Note that this error is
692issued on exit from the C<default> block, so you won't get the
693error if you use an explicit C<continue>.)
694
6df41af2
GS
695=item Can't do inplace edit: %s is not a regular file
696
be771a83 697(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 698a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 699
a0d0e21e
LW
700=item Can't do inplace edit on %s: %s
701
be771a83
GS
702(S inplace) The creation of the new file failed for the indicated
703reason.
a0d0e21e 704
54310121 705=item Can't do inplace edit without backup
a0d0e21e 706
be771a83
GS
707(F) You're on a system such as MS-DOS that gets confused if you try
708reading from a deleted (but still opened) file. You have to say
709C<-i.bak>, or some such.
a0d0e21e 710
10f9c03d 711=item Can't do inplace edit: %s would not be unique
a0d0e21e 712
e476b1b5 713(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
714characters and Perl was unable to create a unique filename during
715inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 716
a0d0e21e
LW
717=item Can't do waitpid with flags
718
be771a83
GS
719(F) This machine doesn't have either waitpid() or wait4(), so only
720waitpid() without flags is emulated.
a0d0e21e 721
a0d0e21e
LW
722=item Can't emulate -%s on #! line
723
be771a83
GS
724(F) The #! line specifies a switch that doesn't make sense at this
725point. For example, it'd be kind of silly to put a B<-x> on the #!
726line.
a0d0e21e 727
1109a392
MHM
728=item Can't %s %s-endian %ss on this platform
729
730(F) Your platform's byte-order is neither big-endian nor little-endian,
731or it has a very strange pointer size. Packing and unpacking big- or
732little-endian floating point values and pointers may not be possible.
733See L<perlfunc/pack>.
734
a0d0e21e
LW
735=item Can't exec "%s": %s
736
d1be9408 737(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
738named program for the indicated reason. Typical reasons include: the
739permissions were wrong on the file, the file wasn't found in
740C<$ENV{PATH}>, the executable in question was compiled for another
741architecture, or the #! line in a script points to an interpreter that
742can't be run for similar reasons. (Or maybe your system doesn't support
743#! at all.)
a0d0e21e
LW
744
745=item Can't exec %s
746
be771a83
GS
747(F) Perl was trying to execute the indicated program for you because
748that's what the #! line said. If that's not what you wanted, you may
749need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
750
751=item Can't execute %s
752
be771a83
GS
753(F) You used the B<-S> switch, but the copies of the script to execute
754found in the PATH did not have correct permissions.
2a92aaa0 755
6df41af2 756=item Can't find an opnumber for "%s"
2a92aaa0 757
be771a83
GS
758(F) A string of a form C<CORE::word> was given to prototype(), but there
759is no builtin with the name C<word>.
6df41af2 760
56ca2fc0
JH
761=item Can't find %s character property "%s"
762
763(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 764could not be found. Maybe you misspelled the name of the property?
e1b711da 765See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 766for a complete list of available official properties.
56ca2fc0 767
6df41af2
GS
768=item Can't find label %s
769
be771a83
GS
770(F) You said to goto a label that isn't mentioned anywhere that it's
771possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
772
773=item Can't find %s on PATH
774
be771a83
GS
775(F) You used the B<-S> switch, but the script to execute could not be
776found in the PATH.
a0d0e21e 777
6df41af2 778=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 779
be771a83
GS
780(F) You used the B<-S> switch, but the script to execute could not be
781found in the PATH, or at least not with the correct permissions. The
782script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
783
784=item Can't find string terminator %s anywhere before EOF
785
be771a83
GS
786(F) Perl strings can stretch over multiple lines. This message means
787that the closing delimiter was omitted. Because bracketed quotes count
788nesting levels, the following is missing its final parenthesis:
a0d0e21e 789
fb73857a
PP
790 print q(The character '(' starts a side comment.);
791
97b3d10f 792If you're getting this error from a here-document, you may have
b6b8cb97
FC
793included unseen whitespace before or after your closing tag or there
794may not be a linebreak after it. A good programmer's editor will have
795a way to help you find these characters (or lack of characters). See
796L<perlop> for the full details on here-documents.
a0d0e21e 797
660a4616
ST
798=item Can't find Unicode property definition "%s"
799
5f8ad6b6
FC
800(F) You may have tried to use C<\p> which means a Unicode
801property (for example C<\p{Lu}> matches all uppercase
fa816bf3 802letters). If you did mean to use a Unicode property, see
e1b711da 803L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 804for a complete list of available properties. If you didn't
fa816bf3
FC
805mean to use a Unicode property, escape the C<\p>, either by
806C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 807until C<\E>).
660a4616 808
b3647a36 809=item Can't fork: %s
a0d0e21e 810
be771a83
GS
811(F) A fatal error occurred while trying to fork while opening a
812pipeline.
a0d0e21e 813
b3647a36
SR
814=item Can't fork, trying again in 5 seconds
815
c973c02e 816(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
817after five seconds.
818
748a9306
LW
819=item Can't get filespec - stale stat buffer?
820
be771a83
GS
821(S) A warning peculiar to VMS. This arises because of the difference
822between access checks under VMS and under the Unix model Perl assumes.
823Under VMS, access checks are done by filename, rather than by bits in
824the stat buffer, so that ACLs and other protections can be taken into
825account. Unfortunately, Perl assumes that the stat buffer contains all
826the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 827the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
828the device name and FID present in the stat buffer, but this works only
829if you haven't made a subsequent call to the CRTL stat() routine,
830because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
831appears, the name lookup failed, and the access-checking routine gave up
832and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
833routine knows about the Perl C<stat> operator and file tests, so you
834shouldn't ever see this warning in response to a Perl command; it arises
835only if some internal code takes stat buffers lightly.)
748a9306 836
a0d0e21e
LW
837=item Can't get pipe mailbox device name
838
be771a83
GS
839(P) An error peculiar to VMS. After creating a mailbox to act as a
840pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
841
842=item Can't get SYSGEN parameter value for MAXBUF
843
748a9306
LW
844(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
845mailbox buffers to be, and didn't get an answer.
a0d0e21e 846
6df41af2 847=item Can't "goto" into the middle of a foreach loop
a0d0e21e 848
be771a83
GS
849(F) A "goto" statement was executed to jump into the middle of a foreach
850loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
851
852=item Can't "goto" out of a pseudo block
853
be771a83
GS
854(F) A "goto" statement was executed to jump out of what might look like
855a block, except that it isn't a proper block. This usually occurs if
856you tried to jump out of a sort() block or subroutine, which is a no-no.
857See L<perlfunc/goto>.
a0d0e21e 858
5a25739d
FC
859=item Can't goto subroutine from an eval-%s
860
861(F) The "goto subroutine" call can't be used to jump out of an eval
862"string" or block.
863
9850bf21 864=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 865
9850bf21
RH
866(F) The "goto subroutine" call can't be used to jump out of the
867comparison sub for a sort(), or from a similar callback (such
868as the reduce() function in List::Util).
869
6df41af2
GS
870=item Can't goto subroutine outside a subroutine
871
be771a83
GS
872(F) The deeply magical "goto subroutine" call can only replace one
873subroutine call for another. It can't manufacture one out of whole
874cloth. In general you should be calling it out of only an AUTOLOAD
875routine anyway. See L<perlfunc/goto>.
6df41af2 876
0b5b802d
GS
877=item Can't ignore signal CHLD, forcing to default
878
be771a83
GS
879(W signal) Perl has detected that it is being run with the SIGCHLD
880signal (sometimes known as SIGCLD) disabled. Since disabling this
881signal will interfere with proper determination of exit status of child
882processes, Perl has reset the signal to its default value. This
883situation typically indicates that the parent program under which Perl
884may be running (e.g. cron) is being very careless.
0b5b802d 885
e2c0f81f
DG
886=item Can't kill a non-numeric process ID
887
888(F) Process identifiers must be (signed) integers. It is a fatal error to
889attempt to kill() an undefined, empty-string or otherwise non-numeric
890process identifier.
891
6df41af2 892=item Can't "last" outside a loop block
4633a7c4 893
6df41af2 894(F) A "last" statement was executed to break out of the current block,
be771a83
GS
895except that there's this itty bitty problem called there isn't a current
896block. Note that an "if" or "else" block doesn't count as a "loopish"
897block, as doesn't a block given to sort(), map() or grep(). You can
898usually double the curlies to get the same effect though, because the
899inner curlies will be considered a block that loops once. See
900L<perlfunc/last>.
4633a7c4 901
2c7d6b9c
RGS
902=item Can't linearize anonymous symbol table
903
904(F) Perl tried to calculate the method resolution order (MRO) of a
905package, but failed because the package stash has no name.
906
b8170e59
JB
907=item Can't load '%s' for module %s
908
6903afa2
FC
909(F) The module you tried to load failed to load a dynamic extension.
910This may either mean that you upgraded your version of perl to one
911that is incompatible with your old dynamic extensions (which is known
912to happen between major versions of perl), or (more likely) that your
913dynamic extension was built against an older version of the library
914that is installed on your system. You may need to rebuild your old
915dynamic extensions.
b8170e59 916
748a9306
LW
917=item Can't localize lexical variable %s
918
2ba9eb46 919(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
920lexical variable using "my" or "state". This is not allowed. If you
921want to localize a package variable of the same name, qualify it with
922the package name.
748a9306 923
6df41af2 924=item Can't localize through a reference
4727527e 925
6df41af2
GS
926(F) You said something like C<local $$ref>, which Perl can't currently
927handle, because when it goes to restore the old value of whatever $ref
be771a83 928pointed to after the scope of the local() is finished, it can't be sure
64977eb6 929that $ref will still be a reference.
4727527e 930
ea071790 931=item Can't locate %s
ec889f3a 932
fa816bf3
FC
933(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
934Perl looks for the file in all the locations mentioned in @INC, unless
935the file name included the full path to the file. Perhaps you need
936to set the PERL5LIB or PERL5OPT environment variable to say where the
937extra library is, or maybe the script needs to add the library name
be771a83
GS
938to @INC. Or maybe you just misspelled the name of the file. See
939L<perlfunc/require> and L<lib>.
a0d0e21e 940
6df41af2
GS
941=item Can't locate auto/%s.al in @INC
942
be771a83
GS
943(F) A function (or method) was called in a package which allows
944autoload, but there is no function to autoload. Most probable causes
945are a misprint in a function/method name or a failure to C<AutoSplit>
946the file, say, by doing C<make install>.
6df41af2 947
b8170e59
JB
948=item Can't locate loadable object for module %s in @INC
949
950(F) The module you loaded is trying to load an external library, like
d70d8e57 951for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
952unable to locate this library. See L<DynaLoader>.
953
a0d0e21e
LW
954=item Can't locate object method "%s" via package "%s"
955
956(F) You called a method correctly, and it correctly indicated a package
957functioning as a class, but that package doesn't define that particular
2ba9eb46 958method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
959
960=item Can't locate package %s for @%s::ISA
961
be771a83
GS
962(W syntax) The @ISA array contained the name of another package that
963doesn't seem to exist.
a0d0e21e 964
2f7da168
RK
965=item Can't locate PerlIO%s
966
967(F) You tried to use in open() a PerlIO layer that does not exist,
968e.g. open(FH, ">:nosuchlayer", "somefile").
969
f4ad53f4 970=item Can't make list assignment to %ENV on this system
3e3baf6d 971
be771a83
GS
972(F) List assignment to %ENV is not supported on some systems, notably
973VMS.
3e3baf6d 974
cd40cd58
NC
975=item Can't make loaded symbols global on this platform while loading %s
976
ff9c1ae8 977(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
978that symbols from the stated file are made available globally within the
979process, but that functionality is not available on this platform. Whilst
980the module likely will still work, this may prevent the perl interpreter
981from loading other XS-based extensions which need to link directly to
982functions defined in the C or XS code in the stated file.
983
a0d0e21e
LW
984=item Can't modify %s in %s
985
be771a83
GS
986(F) You aren't allowed to assign to the item indicated, or otherwise try
987to change it, such as with an auto-increment.
a0d0e21e 988
54310121 989=item Can't modify nonexistent substring
a0d0e21e
LW
990
991(P) The internal routine that does assignment to a substr() was handed
992a NULL.
993
6df41af2
GS
994=item Can't modify non-lvalue subroutine call
995
996(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 997such. See L<perlsub/"Lvalue subroutines">.
6df41af2 998
5f05dabc 999=item Can't msgrcv to read-only var
a0d0e21e 1000
5f05dabc 1001(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1002buffer.
1003
6df41af2
GS
1004=item Can't "next" outside a loop block
1005
1006(F) A "next" statement was executed to reiterate the current block, but
1007there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1008count as a "loopish" block, as doesn't a block given to sort(), map() or
1009grep(). You can usually double the curlies to get the same effect
1010though, because the inner curlies will be considered a block that loops
1011once. See L<perlfunc/next>.
6df41af2 1012
a0d0e21e
LW
1013=item Can't open %s: %s
1014
c47ff5f1 1015(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1016filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1017switches, or explicitly, failed for the indicated reason. Usually
1018this is because you don't have read permission for a file which
1019you named on the command line.
1020
1021(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1022your operating system's equivalent) could not be opened.
a0d0e21e 1023
9a869a14
RGS
1024=item Can't open a reference
1025
1026(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1027using the 3-arg open() syntax:
9a869a14
RGS
1028
1029 open FH, '>', $ref;
1030
1031but your version of perl is compiled without perlio, and this form of
1032open is not supported.
1033
a0d0e21e
LW
1034=item Can't open bidirectional pipe
1035
be771a83
GS
1036(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1037You can try any of several modules in the Perl library to do this, such
1038as IPC::Open2. Alternately, direct the pipe's output to a file using
1039">", and then read it in under a different file handle.
a0d0e21e 1040
748a9306
LW
1041=item Can't open error file %s as stderr
1042
be771a83
GS
1043(F) An error peculiar to VMS. Perl does its own command line
1044redirection, and couldn't open the file specified after '2>' or '2>>' on
1045the command line for writing.
748a9306
LW
1046
1047=item Can't open input file %s as stdin
1048
be771a83
GS
1049(F) An error peculiar to VMS. Perl does its own command line
1050redirection, and couldn't open the file specified after '<' on the
1051command line for reading.
748a9306
LW
1052
1053=item Can't open output file %s as stdout
1054
be771a83
GS
1055(F) An error peculiar to VMS. Perl does its own command line
1056redirection, and couldn't open the file specified after '>' or '>>' on
1057the command line for writing.
748a9306
LW
1058
1059=item Can't open output pipe (name: %s)
1060
be771a83
GS
1061(P) An error peculiar to VMS. Perl does its own command line
1062redirection, and couldn't open the pipe into which to send data destined
1063for stdout.
748a9306 1064
3b1cf97d 1065=item Can't open perl script "%s": %s
a0d0e21e
LW
1066
1067(F) The script you specified can't be opened for the indicated reason.
1068
fa3aa65a
JC
1069If you're debugging a script that uses #!, and normally relies on the
1070shell's $PATH search, the -S option causes perl to do that search, so
1071you don't have to type the path or C<`which $scriptname`>.
1072
6df41af2
GS
1073=item Can't read CRTL environ
1074
1075(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1076from the CRTL's internal environment array and discovered the array was
1077missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1078or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1079searched.
6df41af2 1080
6df41af2
GS
1081=item Can't "redo" outside a loop block
1082
1083(F) A "redo" statement was executed to restart the current block, but
1084there isn't a current block. Note that an "if" or "else" block doesn't
1085count as a "loopish" block, as doesn't a block given to sort(), map()
1086or grep(). You can usually double the curlies to get the same effect
1087though, because the inner curlies will be considered a block that
1088loops once. See L<perlfunc/redo>.
1089
64977eb6 1090=item Can't remove %s: %s, skipping file
10f9c03d 1091
be771a83
GS
1092(S inplace) You requested an inplace edit without creating a backup
1093file. Perl was unable to remove the original file to replace it with
1094the modified file. The file was left unmodified.
10f9c03d 1095
a0d0e21e
LW
1096=item Can't rename %s to %s: %s, skipping file
1097
e476b1b5 1098(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1099probably because you don't have write permission to the directory.
a0d0e21e 1100
748a9306
LW
1101=item Can't reopen input pipe (name: %s) in binary mode
1102
be771a83
GS
1103(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1104to reopen it to accept binary data. Alas, it failed.
748a9306 1105
4f12ec0e
FC
1106=item Can't reset %ENV on this system
1107
1108(F) You called C<reset('E')> or similar, which tried to reset
1109all variables in the current package beginning with "E". In
1110the main package, that includes %ENV. Resetting %ENV is not
1111supported on some systems, notably VMS.
1112
fe13d51d 1113=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1114
1fa582fa
FC
1115(F)(P) Error resolving overloading specified by a method name (as
1116opposed to a subroutine reference): no such method callable via the
1117package. If the method name is C<???>, this is an internal error.
6df41af2 1118
cd06dffe
GS
1119=item Can't return %s from lvalue subroutine
1120
be771a83
GS
1121(F) Perl detected an attempt to return illegal lvalues (such as
1122temporary or readonly values) from a subroutine used as an lvalue. This
1123is not allowed.
cd06dffe 1124
96ebfdd7
RK
1125=item Can't return outside a subroutine
1126
1127(F) The return statement was executed in mainline code, that is, where
1128there was no subroutine call to return out of. See L<perlsub>.
1129
78f9721b
SM
1130=item Can't return %s to lvalue scalar context
1131
6903afa2
FC
1132(F) You tried to return a complete array or hash from an lvalue
1133subroutine, but you called the subroutine in a way that made Perl
1134think you meant to return only one value. You probably meant to
1135write parentheses around the call to the subroutine, which tell
1136Perl that the call should be in list context.
78f9721b 1137
a0d0e21e
LW
1138=item Can't stat script "%s"
1139
be771a83
GS
1140(P) For some reason you can't fstat() the script even though you have it
1141open already. Bizarre.
a0d0e21e 1142
a0d0e21e
LW
1143=item Can't take log of %g
1144
fb73857a 1145(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1146negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1147standard with Perl, though, if you really want to do that for the
1148negative numbers.
a0d0e21e
LW
1149
1150=item Can't take sqrt of %g
1151
1152(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1153negative number. There's a Math::Complex package that comes standard
1154with Perl, though, if you really want to do that.
a0d0e21e
LW
1155
1156=item Can't undef active subroutine
1157
1158(F) You can't undefine a routine that's currently running. You can,
1159however, redefine it while it's running, and you can even undef the
1160redefined subroutine while the old routine is running. Go figure.
1161
c81225bc 1162=item Can't upgrade %s (%d) to %d
a0d0e21e 1163
be771a83
GS
1164(P) The internal sv_upgrade routine adds "members" to an SV, making it
1165into a more specialized kind of SV. The top several SV types are so
1166specialized, however, that they cannot be interconverted. This message
1167indicates that such a conversion was attempted.
a0d0e21e 1168
6651ba0b
FC
1169=item Can't use '%c' after -mname
1170
1171(F) You tried to call perl with the B<-m> switch, but you put something
1172other than "=" after the module name.
1173
1f1ec7b5
KW
1174=item Can't use a hash as a reference
1175
1176(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1177C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1178<= 5.22.0 used to allow this syntax, but shouldn't
1179have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1180
1181=item Can't use an array as a reference
1182
1183(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1184C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1185used to allow this syntax, but shouldn't have. This
1186was deprecated in perl 5.6.1.
1f1ec7b5 1187
1db89ea5
BS
1188=item Can't use anonymous symbol table for method lookup
1189
e27ad1f2 1190(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1191table that doesn't have a name. Symbol tables can become anonymous
1192for example by undefining stashes: C<undef %Some::Package::>.
1193
96ebfdd7
RK
1194=item Can't use an undefined value as %s reference
1195
1196(F) A value used as either a hard reference or a symbolic reference must
1197be a defined value. This helps to delurk some insidious errors.
1198
6df41af2
GS
1199=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1200
be771a83
GS
1201(F) Only hard references are allowed by "strict refs". Symbolic
1202references are disallowed. See L<perlref>.
6df41af2 1203
90b75b61 1204=item Can't use %! because Errno.pm is not available
1d2dff63 1205
20561843 1206(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1207Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1208provide symbolic names for C<$!> errno values.
1209
1109a392
MHM
1210=item Can't use both '<' and '>' after type '%c' in %s
1211
1212(F) A type cannot be forced to have both big-endian and little-endian
1213byte-order at the same time, so this combination of modifiers is not
1214allowed. See L<perlfunc/pack>.
1215
e35475de
KW
1216=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1217
1218(F) defined() is not useful on arrays because it
1219checks for an undefined I<scalar> value. If you want to see if the
1220array is empty, just use C<if (@array) { # not empty }> for example.
1221
1222=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1223
1224(F) C<defined()> is not usually right on hashes.
1225
1226Although C<defined %hash> is false on a plain not-yet-used hash, it
1227becomes true in several non-obvious circumstances, including iterators,
1228weak references, stash names, even remaining true after C<undef %hash>.
1229These things make C<defined %hash> fairly useless in practice, so it now
1230generates a fatal error.
1231
1232If a check for non-empty is what you wanted then just put it in boolean
1233context (see L<perldata/Scalar values>):
1234
1235 if (%hash) {
1236 # not empty
1237 }
1238
1239If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1240variable exists then that's never really been reliable, and isn't
1241a good way to enquire about the features of a package, or whether
1242it's loaded, etc.
1243
6df41af2
GS
1244=item Can't use %s for loop variable
1245
be771a83
GS
1246(F) Only a simple scalar variable may be used as a loop variable on a
1247foreach.
6df41af2 1248
aab6a793 1249=item Can't use global %s in "%s"
6df41af2 1250
be771a83
GS
1251(F) You tried to declare a magical variable as a lexical variable. This
1252is not allowed, because the magic can be tied to only one location
1253(namely the global variable) and it would be incredibly confusing to
1254have variables in your program that looked like magical variables but
6df41af2
GS
1255weren't.
1256
6d3b25aa
RGS
1257=item Can't use '%c' in a group with different byte-order in %s
1258
1259(F) You attempted to force a different byte-order on a type
1260that is already inside a group with a byte-order modifier.
1261For example you cannot force little-endianness on a type that
1262is inside a big-endian group.
1263
c07a80fd
PP
1264=item Can't use "my %s" in sort comparison
1265
1266(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1267You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1268and the variable had earlier been declared as a lexical variable.
1269Either qualify the sort variable with the package name, or rename the
1270lexical variable.
1271
a0d0e21e
LW
1272=item Can't use %s ref as %s ref
1273
1274(F) You've mixed up your reference types. You have to dereference a
1275reference of the type needed. You can use the ref() function to
1276test the type of the reference, if need be.
1277
748a9306 1278=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1279
5e634d20
FC
1280=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1281
b41bf23f
FC
1282(F) You've told Perl to dereference a string, something which
1283C<use strict> blocks to prevent it happening accidentally. See
1284L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1285in a double-quoted string immediately before interpolating a variable,
1286for example in C<"user @$twitter_id">, which says to treat the contents
1287of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1288symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1289
748a9306
LW
1290=item Can't use subscript on %s
1291
1292(F) The compiler tried to interpret a bracketed expression as a
1293subscript. But to the left of the brackets was an expression that
209e7cf1 1294didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1295
6df41af2
GS
1296=item Can't use \%c to mean $%c in expression
1297
75b44862
GS
1298(W syntax) In an ordinary expression, backslash is a unary operator that
1299creates a reference to its argument. The use of backslash to indicate a
1300backreference to a matched substring is valid only as part of a regular
be771a83
GS
1301expression pattern. Trying to do this in ordinary Perl code produces a
1302value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1303instead.
6df41af2 1304
810b8aa5
GS
1305=item Can't weaken a nonreference
1306
1307(F) You attempted to weaken something that was not a reference. Only
1308references can be weakened.
1309
fc7debfb
FC
1310=item Can't "when" outside a topicalizer
1311
1312(F) You have used a when() block that is neither inside a C<foreach>
1313loop nor a C<given> block. (Note that this error is issued on exit
1314from the C<when> block, so you won't get the error if the match fails,
1315or if you use an explicit C<continue>.)
1316
5f05dabc 1317=item Can't x= to read-only value
a0d0e21e 1318
be771a83
GS
1319(F) You tried to repeat a constant value (often the undefined value)
1320with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1321Perhaps you need to copy the value to a temporary, and repeat that.
1322
a04e6aad 1323=item Character following "\c" must be printable ASCII
f9d13529 1324
7357bd17 1325(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1326
727b6379 1327Note that ASCII characters that don't map to control characters are
7357bd17 1328discouraged, and will generate the warning (when enabled)
727b6379 1329L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1330
f337b084 1331=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1332
1333(W pack) You said
1334
1335 pack("C", $x)
1336
1337where $x is either less than 0 or more than 255; the C<"C"> format is
1338only for encoding native operating system characters (ASCII, EBCDIC,
1339and so on) and not for Unicode characters, so Perl behaved as if you meant
1340
1341 pack("C", $x & 255)
1342
1343If you actually want to pack Unicode codepoints, use the C<"U"> format
1344instead.
1345
f337b084 1346=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1347
1348(W pack) You said
1349
1350 pack("c", $x)
1351
1352where $x is either less than -128 or more than 127; the C<"c"> format
1353is only for encoding native operating system characters (ASCII, EBCDIC,
1354and so on) and not for Unicode characters, so Perl behaved as if you meant
1355
1356 pack("c", $x & 255);
1357
1358If you actually want to pack Unicode codepoints, use the C<"U"> format
1359instead.
1360
f337b084
TH
1361=item Character in '%c' format wrapped in unpack
1362
1363(W unpack) You tried something like
1364
1365 unpack("H", "\x{2a1}")
1366
1a147d38 1367where the format expects to process a byte (a character with a value
6903afa2
FC
1368below 256), but a higher value was provided instead. Perl uses the
1369value modulus 256 instead, as if you had provided:
f337b084
TH
1370
1371 unpack("H", "\x{a1}")
1372
5a25739d
FC
1373=item Character in 'W' format wrapped in pack
1374
1375(W pack) You said
1376
1377 pack("U0W", $x)
1378
1379where $x is either less than 0 or more than 255. However, C<U0>-mode
1380expects all values to fall in the interval [0, 255], so Perl behaved
1381as if you meant:
1382
1383 pack("U0W", $x & 255)
1384
f337b084
TH
1385=item Character(s) in '%c' format wrapped in pack
1386
1387(W pack) You tried something like
1388
1389 pack("u", "\x{1f3}b")
1390
1a147d38 1391where the format expects to process a sequence of bytes (character with a
6903afa2 1392value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1393uses the character values modulus 256 instead, as if you had provided:
1394
1395 pack("u", "\x{f3}b")
1396
1397=item Character(s) in '%c' format wrapped in unpack
1398
1399(W unpack) You tried something like
1400
1401 unpack("s", "\x{1f3}b")
1402
1a147d38 1403where the format expects to process a sequence of bytes (character with a
6903afa2 1404value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1405uses the character values modulus 256 instead, as if you had provided:
1406
1407 unpack("s", "\x{f3}b")
1408
f51551f7
FC
1409=item charnames alias definitions may not contain a sequence of multiple spaces
1410
1411(F) You defined a character name which had multiple space characters
1412in a row. Change them to single spaces. Usually these names are
1413defined in the C<:alias> import argument to C<use charnames>, but they
1414could be defined by a translator installed into C<$^H{charnames}>. See
1415L<charnames/CUSTOM ALIASES>.
1416
1417=item charnames alias definitions may not contain trailing white-space
1418
1419(F) You defined a character name which ended in a space
1420character. Remove the trailing space(s). Usually these names are
1421defined in the C<:alias> import argument to C<use charnames>, but they
1422could be defined by a translator installed into C<$^H{charnames}>.
1423See L<charnames/CUSTOM ALIASES>.
1424
1425=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1426
1427(D deprecated, regexp) The \C character class is deprecated, and will
1428become a compile-time error in a future release of perl (tentatively
1429v5.24). This construct allows you to match a single byte of what makes up
1430a multi-byte single UTF8 character, and breaks encapsulation. It is
1431currently also very buggy. If you really need to process the individual
1432bytes, you probably want to convert your string to one where each
1433underlying byte is stored as a character, with utf8::encode().
1434
f866a7cd
FC
1435=item "\c%c" is more clearly written simply as "%s"
1436
1437(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1438non-printable characters. You used it for a printable one, which is better
1439written as simply itself, perhaps preceded by a backslash for non-word
1440characters.
1441
6651ba0b
FC
1442=item Cloning substitution context is unimplemented
1443
1444(F) Creating a new thread inside the C<s///> operator is not supported.
1445
abc7ecad
SP
1446=item closedir() attempted on invalid dirhandle %s
1447
1448(W io) The dirhandle you tried to close is either closed or not really
1449a dirhandle. Check your control flow.
1450
5a25739d
FC
1451=item close() on unopened filehandle %s
1452
1453(W unopened) You tried to close a filehandle that was never opened.
1454
541ed3a9
FC
1455=item Closure prototype called
1456
1457(F) If a closure has attributes, the subroutine passed to an attribute
1458handler is the prototype that is cloned when a new closure is created.
1459This subroutine cannot be called.
1460
49704364
LW
1461=item Code missing after '/'
1462
6903afa2
FC
1463(F) You had a (sub-)template that ends with a '/'. There must be
1464another template code following the slash. See L<perlfunc/pack>.
49704364 1465
5a25739d
FC
1466=item Code point 0x%X is not Unicode, may not be portable
1467
2d88a86a 1468(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1469of U+10FFFF.
1470
1471Perl allows strings to contain a superset of Unicode code points, up
1472to the limit of what is storable in an unsigned integer on your system,
1473but these may not be accepted by other languages/systems. At one time,
1474it was legal in some standards to have code points up to 0x7FFF_FFFF,
1475but not higher. Code points above 0xFFFF_FFFF require larger than a
147632 bit word.
0876b9a0 1477
6df41af2
GS
1478=item %s: Command not found
1479
a892b81a 1480(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1481instead of Perl. Check the #! line, or manually feed your script into
1482Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1483
1484 #!/usr/bin/perl -w
6df41af2 1485
7a2e2cd6
PP
1486=item Compilation failed in require
1487
1488(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1489Perl uses this generic message when none of the errors that it
1490encountered were severe enough to halt compilation immediately.
7a2e2cd6 1491
c3464db5
DD
1492=item Complex regular subexpression recursion limit (%d) exceeded
1493
be771a83
GS
1494(W regexp) The regular expression engine uses recursion in complex
1495situations where back-tracking is required. Recursion depth is limited
1496to 32766, or perhaps less in architectures where the stack cannot grow
1497arbitrarily. ("Simple" and "medium" situations are handled without
1498recursion and are not subject to a limit.) Try shortening the string
1499under examination; looping in Perl code (e.g. with C<while>) rather than
1500in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1501that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1502on I<Mastering Regular Expressions>.)
c3464db5 1503
69282e91 1504=item connect() on closed socket %s
a0d0e21e 1505
be771a83
GS
1506(W closed) You tried to do a connect on a closed socket. Did you forget
1507to check the return value of your socket() call? See
1508L<perlfunc/connect>.
a0d0e21e 1509
e21e7c6a
FC
1510=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1511
1512(F) The subroutine registered to handle constant overloading
1513(see L<overload>) or a custom charnames handler (see
1514L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1515
1516=item Constant(%s): $^H{%s} is not defined
1517
1518(F) The parser found inconsistencies while attempting to define an
1519overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1520L<overload> pragma?
e21e7c6a 1521
779c5bc9
GS
1522=item Constant is not %s reference
1523
1524(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1525is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1526The message indicates the type of reference that was expected. This
be771a83 1527usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1528See L<perlsub/"Constant Functions"> and L<constant>.
1529
4cee8e80
CS
1530=item Constant subroutine %s redefined
1531
aeb94125
FC
1532(W redefine)(S) You redefined a subroutine which had previously
1533been eligible for inlining. See L<perlsub/"Constant Functions">
1534for commentary and workarounds.
4cee8e80 1535
9607fc9c
PP
1536=item Constant subroutine %s undefined
1537
be771a83
GS
1538(W misc) You undefined a subroutine which had previously been eligible
1539for inlining. See L<perlsub/"Constant Functions"> for commentary and
1540workarounds.
9607fc9c 1541
5a25739d
FC
1542=item Constant(%s) unknown
1543
1544(F) The parser found inconsistencies either while attempting
1545to define an overloaded constant, or when trying to find the
1546character name specified in the C<\N{...}> escape. Perhaps you
1547forgot to load the corresponding L<overload> pragma?.
1548
e7ea3e70
IZ
1549=item Copy method did not return a reference
1550
6903afa2 1551(F) The method which overloads "=" is buggy. See
13a2d996 1552L<overload/Copy Constructor>.
e7ea3e70 1553
4aaa4757
FC
1554=item &CORE::%s cannot be called directly
1555
1556(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1557with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1558in this package cannot yet be called that way, but must be
1559called as barewords. Something like this will work:
1560
1561 BEGIN { *shove = \&CORE::push; }
1562 shove @array, 1,2,3; # pushes on to @array
1563
6798c92b
GS
1564=item CORE::%s is not a keyword
1565
1566(F) The CORE:: namespace is reserved for Perl keywords.
1567
675fa9ff
FC
1568=item Corrupted regexp opcode %d > %d
1569
1570(P) This is either an error in Perl, or, if you're using
1571one, your L<custom regular expression engine|perlreapi>. If not the
1572latter, report the problem through the L<perlbug> utility.
1573
a0d0e21e
LW
1574=item corrupted regexp pointers
1575
1576(P) The regular expression engine got confused by what the regular
1577expression compiler gave it.
1578
1579=item corrupted regexp program
1580
be771a83
GS
1581(P) The regular expression engine got passed a regexp program without a
1582valid magic number.
a0d0e21e 1583
de42a5a9 1584=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1585
1586(P) The malloc package that comes with Perl had an internal failure.
1587
49704364
LW
1588=item Count after length/code in unpack
1589
1590(F) You had an unpack template indicating a counted-length string, but
1591you have also specified an explicit size for the string. See
1592L<perlfunc/pack>.
1593
f2cccb4c
KW
1594=for comment
1595The following are used in lib/diagnostics.t for testing two =items that
1596share the same description. Changes here need to be propagated to there
1597
6651ba0b
FC
1598=item Deep recursion on anonymous subroutine
1599
a0d0e21e
LW
1600=item Deep recursion on subroutine "%s"
1601
be771a83
GS
1602(W recursion) This subroutine has called itself (directly or indirectly)
1603100 times more than it has returned. This probably indicates an
1604infinite recursion, unless you're writing strange benchmark programs, in
1605which case it indicates something else.
a0d0e21e 1606
aad1d01f
NC
1607This threshold can be changed from 100, by recompiling the F<perl> binary,
1608setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1609
e0e4a6e3
FC
1610=item (?(DEFINE)....) does not allow branches in regex; marked by
1611S<<-- HERE> in m/%s/
bcb95744 1612
6903afa2 1613(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1614most likely cause of this error is that you left out a parenthesis inside
1615of the C<....> part.
1616
9e3ec65c 1617The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1618discovered.
1619
62658f4d
PM
1620=item %s defines neither package nor VERSION--version check failed
1621
1622(F) You said something like "use Module 42" but in the Module file
1623there are neither package declarations nor a C<$VERSION>.
1624
36447869
FC
1625=item delete argument is index/value array slice, use array slice
1626
1627(F) You used index/value array slice syntax (C<%array[...]>) as
1628the argument to C<delete>. You probably meant C<@array[...]> with
1629an @ symbol instead.
1630
1631=item delete argument is key/value hash slice, use hash slice
1632
1633(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1634C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1635
0ffcbc25
FC
1636=item delete argument is not a HASH or ARRAY element or slice
1637
4a0af295 1638(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1639such as:
1640
1641 $foo{$bar}
1642 $ref->{"susie"}[12]
1643
1644or a hash or array slice, such as:
1645
1646 @foo[$bar, $baz, $xyzzy]
1647 @{$ref->[12]}{"susie", "queue"}
1648
fc36a67e
PP
1649=item Delimiter for here document is too long
1650
be771a83
GS
1651(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1652long for Perl to handle. You have to be seriously twisted to write code
1653that triggers this error.
fc36a67e 1654
6d3b25aa
RGS
1655=item Deprecated use of my() in false conditional
1656
fa816bf3
FC
1657(D deprecated) You used a declaration similar to C<my $x if 0>. There
1658has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1659not to be cleared at scope exit when its declaration includes a false
6903afa2 1660conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1661static variable. Since we intend to fix this bug, we don't want people
6903afa2 1662relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1663declaring the variable in a separate block outside the function, eg
36fb85f3 1664
6d3b25aa
RGS
1665 sub f { my $x if 0; return $x++ }
1666
1667becomes
1668
1669 { my $x; sub f { return $x++ } }
1670
ea9d9ebc 1671Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1672lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1673
1674 sub f { state $x; return $x++ }
1675
500ab966
RGS
1676=item DESTROY created new reference to dead object '%s'
1677
1678(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1679just being DESTROYed. Perl is confused, and prefers to abort rather
1680than to create a dangling reference.
500ab966 1681
3cdd684c
TP
1682=item Did not produce a valid header
1683
1684See Server error.
1685
6df41af2
GS
1686=item %s did not return a true value
1687
1688(F) A required (or used) file must return a true value to indicate that
1689it compiled correctly and ran its initialization code correctly. It's
1690traditional to end such a file with a "1;", though any true value would
1691do. See L<perlfunc/require>.
1692
cc507455 1693=item (Did you mean &%s instead?)
4633a7c4 1694
413ff9f6
FC
1695(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1696some such.
4633a7c4 1697
cc507455 1698=item (Did you mean "local" instead of "our"?)
33633739 1699
be771a83
GS
1700(W misc) Remember that "our" does not localize the declared global
1701variable. You have declared it again in the same lexical scope, which
1702seems superfluous.
33633739 1703
cc507455 1704=item (Did you mean $ or @ instead of %?)
a0d0e21e 1705
be771a83
GS
1706(W) You probably said %hash{$key} when you meant $hash{$key} or
1707@hash{@keys}. On the other hand, maybe you just meant %hash and got
1708carried away.
748a9306 1709
7e1af8bc 1710=item Died
5f05dabc
PP
1711
1712(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1713you called it with no args and C<$@> was empty.
5f05dabc 1714
3cdd684c
TP
1715=item Document contains no data
1716
1717See Server error.
1718
62658f4d
PM
1719=item %s does not define %s::VERSION--version check failed
1720
1721(F) You said something like "use Module 42" but the Module did not
943fc58e 1722define a C<$VERSION>.
62658f4d 1723
49704364
LW
1724=item '/' does not take a repeat count
1725
1726(F) You cannot put a repeat count of any kind right after the '/' code.
1727See L<perlfunc/pack>.
1728
95cb0d72
FC
1729=item Don't know how to get file name
1730
1731(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1732somehow called on another platform. This should not happen.
1733
4021c788 1734=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1735
1736(P) The internal handling of magical variables has been cursed.
1737
1738=item do_study: out of memory
1739
1740(P) This should have been caught by safemalloc() instead.
1741
6df41af2
GS
1742=item (Do you need to predeclare %s?)
1743
56da5a46
RGS
1744(S syntax) This is an educated guess made in conjunction with the message
1745"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1746name is being referenced that hasn't been declared yet. This may be
1747because of ordering problems in your file, or because of a missing
be771a83
GS
1748"sub", "package", "require", or "use" statement. If you're referencing
1749something that isn't defined yet, you don't actually have to define the
1750subroutine or package before the current location. You can use an empty
1751"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1752
ac206dc8
RGS
1753=item dump() better written as CORE::dump()
1754
1755(W misc) You used the obsolescent C<dump()> built-in function, without fully
1756qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1757
84d78eb7
YO
1758=item dump is not supported
1759
1760(F) Your machine doesn't support dump/undump.
1761
a0d0e21e
LW
1762=item Duplicate free() ignored
1763
be771a83
GS
1764(S malloc) An internal routine called free() on something that had
1765already been freed.
a0d0e21e 1766
1109a392
MHM
1767=item Duplicate modifier '%c' after '%c' in %s
1768
35f0cd76
FC
1769(W unpack) You have applied the same modifier more than once after a
1770type in a pack template. See L<perlfunc/pack>.
1109a392 1771
0953b66b
FC
1772=item each on reference is experimental
1773
0773cb3e
FC
1774(S experimental::autoderef) C<each> with a scalar argument is experimental
1775and may change or be removed in a future Perl version. If you want to
1776take the risk of using this feature, simply disable this warning:
0953b66b 1777
d401967c 1778 no warnings "experimental::autoderef";
0953b66b 1779
4633a7c4
LW
1780=item elseif should be elsif
1781
fa816bf3
FC
1782(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1783it's ugly. Your code will be interpreted as an attempt to call a method
1784named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1785unlikely to be what you want.
1786
e0e4a6e3 1787=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1788
af6f566e 1789(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1790described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1791a regular expression without specifying the property name.
ab13f0c7 1792
85ab1d1d 1793=item entering effective %s failed
5ff3f7a4 1794
85ab1d1d 1795(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1796effective uids or gids failed.
1797
c038024b
RGS
1798=item %ENV is aliased to %s
1799
1800(F) You're running under taint mode, and the C<%ENV> variable has been
1801aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1802program's environment. This is potentially insecure.
c038024b 1803
748a9306
LW
1804=item Error converting file specification %s
1805
5f05dabc 1806(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1807specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1808single form when it must operate on them directly. Either you've passed
1809an invalid file specification to Perl, or you've found a case the
1810conversion routines don't handle. Drat.
748a9306 1811
ad19ef22 1812=item Eval-group in insecure regular expression
e4d48cc9 1813
be771a83
GS
1814(F) Perl detected tainted data when trying to compile a regular
1815expression that contains the C<(?{ ... })> zero-width assertion, which
1816is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1817
ad19ef22 1818=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1819
be771a83
GS
1820(F) Perl tried to compile a regular expression containing the
1821C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1822pattern contains interpolated values. Since that is a security risk,
1823it is not allowed. If you insist, you may still do this by using the
1824C<re 'eval'> pragma or by explicitly building the pattern from an
1825interpolated string at run time and using that in an eval(). See
1826L<perlre/(?{ code })>.
e4d48cc9 1827
ad19ef22 1828=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1829
be771a83
GS
1830(F) A regular expression contained the C<(?{ ... })> zero-width
1831assertion, but that construct is only allowed when the C<use re 'eval'>
1832pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1833
e0e4a6e3
FC
1834=item EVAL without pos change exceeded limit in regex; marked by
1835S<<-- HERE> in m/%s/
1a147d38
YO
1836
1837(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1838any text. Restructure the pattern so that text is consumed.
1a147d38 1839
9e3ec65c 1840The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1841discovered.
1842
fc36a67e
PP
1843=item Excessively long <> operator
1844
1845(F) The contents of a <> operator may not exceed the maximum size of a
1846Perl identifier. If you're just trying to glob a long list of
1847filenames, try using the glob() operator, or put the filenames into a
1848variable and glob that.
1849
ed9aa3b7
SG
1850=item exec? I'm not *that* kind of operating system
1851
af8bb25a 1852(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1853OS. See L<perlport>.
ed9aa3b7 1854
fe13d51d 1855=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1856
1857(F) The final summary message when a Perl compilation fails.
1858
0ffcbc25
FC
1859=item exists argument is not a HASH or ARRAY element or a subroutine
1860
4a0af295 1861(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1862subroutine with an ampersand, such as:
1863
1864 $foo{$bar}
1865 $ref->{"susie"}[12]
1866 &do_something
1867
1868=item exists argument is not a subroutine name
1869
ccfc2567
FC
1870(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1871and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1872
a0d0e21e
LW
1873=item Exiting eval via %s
1874
be771a83
GS
1875(W exiting) You are exiting an eval by unconventional means, such as a
1876goto, or a loop control statement.
e476b1b5
GS
1877
1878=item Exiting format via %s
1879
9a2ff54b 1880(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1881goto, or a loop control statement.
a0d0e21e 1882
0a753a76
PP
1883=item Exiting pseudo-block via %s
1884
be771a83
GS
1885(W exiting) You are exiting a rather special block construct (like a
1886sort block or subroutine) by unconventional means, such as a goto, or a
1887loop control statement. See L<perlfunc/sort>.
0a753a76 1888
a0d0e21e
LW
1889=item Exiting subroutine via %s
1890
be771a83
GS
1891(W exiting) You are exiting a subroutine by unconventional means, such
1892as a goto, or a loop control statement.
a0d0e21e
LW
1893
1894=item Exiting substitution via %s
1895
be771a83
GS
1896(W exiting) You are exiting a substitution by unconventional means, such
1897as a return, a goto, or a loop control statement.
a0d0e21e 1898
e0e4a6e3 1899=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1900
675fa9ff 1901(F) You wrote something like
c608e803
KW
1902
1903 (?13
1904
1905to denote a capturing group of the form
1906L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1907but omitted the C<")">.
1908
e0e4a6e3 1909=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1910
8b6fbf55
FC
1911(F) The C<(?[...])> extended character class regular expression construct
1912only allows character classes (including character class escapes like
1913C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1914containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1915This allows a regular expression containing just C<(?[...])> to be
1916interpolated. If you see this error message, then you probably
1917have some other C<(?...)> construct inside your character class. See
1918L<perlrecharclass/Extended Bracketed Character Classes>.
1919
30d9c59b
Z
1920=item Experimental subroutine signatures not enabled
1921
1922(F) To use subroutine signatures, you must first enable them:
1923
caa35032 1924 no warnings "experimental::signatures";
30d9c59b
Z
1925 use feature "signatures";
1926 sub foo ($left, $right) { ... }
1927
6da34ecb
FC
1928=item Experimental "%s" subs not enabled
1929
1930(F) To use lexical subs, you must first enable them:
1931
1932 no warnings 'experimental::lexical_subs';
1933 use feature 'lexical_subs';
1934 my sub foo { ... }
1935
7b8d334a
GS
1936=item Explicit blessing to '' (assuming package main)
1937
be771a83
GS
1938(W misc) You are blessing a reference to a zero length string. This has
1939the effect of blessing the reference into the package main. This is
1940usually not what you want. Consider providing a default target package,
1941e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1942
6df41af2
GS
1943=item %s: Expression syntax
1944
be771a83
GS
1945(A) You've accidentally run your script through B<csh> instead of Perl.
1946Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1947
1948=item %s failed--call queue aborted
1949
3c10abe3
AG
1950(F) An untrapped exception was raised while executing a UNITCHECK,
1951CHECK, INIT, or END subroutine. Processing of the remainder of the
1952queue of such routines has been prematurely ended.
6df41af2 1953
e0e4a6e3 1954=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1955
98d31c73 1956(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1957character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1958in your false range is interpreted as a literal "-". In a C<(?[...])>
1959construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1960the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1961the problem was discovered. See L<perlre>.
73b437c8 1962
1b1ee2ef 1963=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1964
be771a83
GS
1965(P) An error peculiar to VMS. Something untoward happened in a VMS
1966system service or RTL routine; Perl's exit status should provide more
1967details. The filename in "at %s" and the line number in "line %d" tell
1968you which section of the Perl source code is distressed.
a0d0e21e
LW
1969
1970=item fcntl is not implemented
1971
1972(F) Your machine apparently doesn't implement fcntl(). What is this, a
1973PDP-11 or something?
1974
22846ab4
AB
1975=item FETCHSIZE returned a negative value
1976
1977(F) A tied array claimed to have a negative number of elements, which
1978is not possible.
1979
f337b084
TH
1980=item Field too wide in 'u' format in pack
1981
d8b5cc61 1982(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1983which can't encode values above 63. So there is no point in asking for
1984a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1985C<u63> as the format.
f337b084 1986
af8c498a 1987=item Filehandle %s opened only for input
a0d0e21e 1988
6c8d78fb
HS
1989(W io) You tried to write on a read-only filehandle. If you intended
1990it to be a read-write filehandle, you needed to open it with "+<" or
1991"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1992write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1993
af8c498a 1994=item Filehandle %s opened only for output
a0d0e21e 1995
6c8d78fb
HS
1996(W io) You tried to read from a filehandle opened only for writing, If
1997you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1998with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1999read from the file, use "<". See L<perlfunc/open>. Another possibility
2000is that you attempted to open filedescriptor 0 (also known as STDIN) for
2001output (maybe you closed STDIN earlier?).
97828cef
RGS
2002
2003=item Filehandle %s reopened as %s only for input
2004
2005(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2006as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2007previously.
2008
2009=item Filehandle STDIN reopened as %s only for output
2010
2011(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2012as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2013
2014=item Final $ should be \$ or $name
2015
2016(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2017a literal dollar sign, or was meant to introduce a variable name that
2018happens to be missing. So you have to put either the backslash or the
2019name.
a0d0e21e 2020
56e90b21
GS
2021=item flock() on closed filehandle %s
2022
be771a83 2023(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2024some time before now. Check your control flow. flock() operates on
be771a83
GS
2025filehandles. Are you attempting to call flock() on a dirhandle by the
2026same name?
56e90b21 2027
6df41af2
GS
2028=item Format not terminated
2029
2030(F) A format must be terminated by a line with a solitary dot. Perl got
2031to the end of your file without finding such a line.
2032
a0d0e21e
LW
2033=item Format %s redefined
2034
e476b1b5 2035(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2036
2037 {
271595cc 2038 no warnings 'redefine';
a0d0e21e
LW
2039 eval "format NAME =...";
2040 }
2041
a0d0e21e
LW
2042=item Found = in conditional, should be ==
2043
e476b1b5 2044(W syntax) You said
a0d0e21e
LW
2045
2046 if ($foo = 123)
2047
2048when you meant
2049
2050 if ($foo == 123)
2051
2052(or something like that).
2053
6df41af2
GS
2054=item %s found where operator expected
2055
56da5a46
RGS
2056(S syntax) The Perl lexer knows whether to expect a term or an operator.
2057If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2058operator, it gives you this warning. Usually it indicates that an
2059operator or delimiter was omitted, such as a semicolon.
6df41af2 2060
a0d0e21e
LW
2061=item gdbm store returned %d, errno %d, key "%s"
2062
2063(S) A warning from the GDBM_File extension that a store failed.
2064
2065=item gethostent not implemented
2066
2067(F) Your C library apparently doesn't implement gethostent(), probably
2068because if it did, it'd feel morally obligated to return every hostname
2069on the Internet.
2070
69282e91 2071=item get%sname() on closed socket %s
a0d0e21e 2072
be771a83
GS
2073(W closed) You tried to get a socket or peer socket name on a closed
2074socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2075
748a9306
LW
2076=item getpwnam returned invalid UIC %#o for user "%s"
2077
2078(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2079C<getpwnam> operator returned an invalid UIC.
2080
6df41af2
GS
2081=item getsockopt() on closed socket %s
2082
be771a83
GS
2083(W closed) You tried to get a socket option on a closed socket. Did you
2084forget to check the return value of your socket() call? See
6df41af2
GS
2085L<perlfunc/getsockopt>.
2086
0f539b13
BF
2087=item given is experimental
2088
675fa9ff
FC
2089(S experimental::smartmatch) C<given> depends on smartmatch, which
2090is experimental, so its behavior may change or even be removed
2091in any future release of perl. See the explanation under
2092L<perlsyn/Experimental Details on given and when>.
0f539b13 2093
6df41af2
GS
2094=item Global symbol "%s" requires explicit package name
2095
a4edf47d 2096(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2097that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2098declared beforehand using "our", or explicitly qualified to say
2099which package the global variable is in (using "::").
6df41af2 2100
e476b1b5
GS
2101=item glob failed (%s)
2102
5ead438e 2103(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2104for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2105pattern that caused the external program to fail and exit with a
be771a83 2106nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2107resulted in a coredump, this may also mean that your csh (C shell)
2108is broken. If so, you should change all of the csh-related variables
2109in config.sh: If you have tcsh, make the variables refer to it as
2110if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2111all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2112think csh is missing. In either case, after editing config.sh, run
75b44862 2113C<./Configure -S> and rebuild Perl.
e476b1b5 2114
a0d0e21e
LW
2115=item Glob not terminated
2116
2117(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2118a term, so it's looking for the corresponding right angle bracket, and
2119not finding it. Chances are you left some needed parentheses out
2120earlier in the line, and you really meant a "less than".
a0d0e21e 2121
b35b96b6
JH
2122=item gmtime(%f) failed
2123
2124(W overflow) You called C<gmtime> with a number that it could not handle:
2125too large, too small, or NaN. The returned value is C<undef>.
2126
bcd05b94 2127=item gmtime(%f) too large
8b56d6ff 2128
e9200be3 2129(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2130it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2131date. This warning is also triggered with NaN (the special
fc003d4b
MS
2132not-a-number value).
2133
bcd05b94 2134=item gmtime(%f) too small
fc003d4b 2135
e9200be3 2136(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2137it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2138
6df41af2 2139=item Got an error from DosAllocMem
a0d0e21e 2140
6df41af2
GS
2141(P) An error peculiar to OS/2. Most probably you're using an obsolete
2142version of Perl, and this should not happen anyway.
a0d0e21e
LW
2143
2144=item goto must have label
2145
2146(F) Unlike with "next" or "last", you're not allowed to goto an
2147unspecified destination. See L<perlfunc/goto>.
2148
6651ba0b
FC
2149=item Goto undefined subroutine%s
2150
2151(F) You tried to call a subroutine with C<goto &sub> syntax, but
2152the indicated subroutine hasn't been defined, or if it was, it
2153has since been undefined.
2154
6fbc9859 2155=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2156S<<-- HERE> in m/%s/
1f4f6bf1
YO
2157
2158(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2159they must start with a non-digit word character. A common cause of
2160this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2161
5a25739d
FC
2162=item ()-group starts with a count
2163
2164(F) A ()-group started with a count. A count is supposed to follow
2165something: a template character or a ()-group. See L<perlfunc/pack>.
2166
fe13d51d 2167=item %s had compilation errors.
6df41af2
GS
2168
2169(F) The final summary message when a C<perl -c> fails.
2170
a0d0e21e
LW
2171=item Had to create %s unexpectedly
2172
be771a83
GS
2173(S internal) A routine asked for a symbol from a symbol table that ought
2174to have existed already, but for some reason it didn't, and had to be
2175created on an emergency basis to prevent a core dump.
a0d0e21e 2176
6df41af2
GS
2177=item %s has too many errors
2178
2179(F) The parser has given up trying to parse the program after 10 errors.
2180Further error messages would likely be uninformative.
2181
61e61fbc
JH
2182=item Hexadecimal float: exponent overflow
2183
2184(W overflow) The hexadecimal floating point has larger exponent
2185than the floating point supports.
2186
2187=item Hexadecimal float: exponent underflow
2188
2189(W overflow) The hexadecimal floating point has smaller exponent
2190than the floating point supports.
2191
cf4f6003
JH
2192=item Hexadecimal float: internal error
2193
2194(F) Something went horribly bad in hexadecimal float handling.
2195
61e61fbc
JH
2196=item Hexadecimal float: mantissa overflow
2197
2198(W overflow) The hexadecimal floating point literal had more bits in
2199the mantissa (the part between the 0x and the exponent, also known as
2200the fraction or the significand) than the floating point supports.
2201
40bca5ae
JH
2202=item Hexadecimal float: precision loss
2203
2204(W overflow) The hexadecimal floating point had internally more
2205digits than could be output. This can be caused by unsupported
2206long double formats, or by 64-bit integers not being available
2207(needed to retrieve the digits under some configurations).
2208
2209=item Hexadecimal float: unsupported long double format
2210
2211(F) You have configured Perl to use long doubles but
2212the internals of the long double format are unknown,
2213therefore the hexadecimal float output is impossible.
2214
252aa082
JH
2215=item Hexadecimal number > 0xffffffff non-portable
2216
e476b1b5 2217(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2218(4294967295) and therefore non-portable between systems. See
2219L<perlport> for more on portability concerns.
252aa082 2220
8903cb82
PP
2221=item Identifier too long
2222
2223(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2224about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2225names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2226of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2227
e0e4a6e3
FC
2228=item Ignoring zero length \N{} in character class in regex; marked by
2229S<<-- HERE> in m/%s/
fc8cd66c 2230
b5e3739b
FC
2231(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2232zero-length sequence. When such an escape is used in a character class
2233its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2234been used, and the correct charname handler is in scope.
2235
6df41af2 2236=item Illegal binary digit %s
f675dbe5 2237
6df41af2 2238(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2239
6df41af2 2240=item Illegal binary digit %s ignored
a0d0e21e 2241
be771a83
GS
2242(W digit) You may have tried to use a digit other than 0 or 1 in a
2243binary number. Interpretation of the binary number stopped before the
2244offending digit.
a0d0e21e 2245
6597eb22
FC
2246=item Illegal character after '_' in prototype for %s : %s
2247
e4d150f1
FC
2248(W illegalproto) An illegal character was found in a prototype
2249declaration. The '_' in a prototype must be followed by a ';',
2250indicating the rest of the parameters are optional, or one of '@'
2251or '%', since those two will accept 0 or more final parameters.
6597eb22 2252
78d0fecf 2253=item Illegal character \%o (carriage return)
4fdae800 2254
d5898338 2255(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2256would any other whitespace, which means you should never see this error
2257when Perl was built using standard options. For some reason, your
2258version of Perl appears to have been built without this support. Talk
2259to your Perl administrator.
4fdae800 2260
d37a9538
ST
2261=item Illegal character in prototype for %s : %s
2262
197afce1 2263(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2264Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2265Perhaps you were trying to write a subroutine signature but didn't enable
2266that feature first (C<use feature 'signatures'>), so your signature was
2267instead interpreted as a bad prototype.
d37a9538 2268
904d85c5
RGS
2269=item Illegal declaration of anonymous subroutine
2270
2271(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2272you must always specify a block of code. See L<perlsub>.
904d85c5 2273
8e742a20
MHM
2274=item Illegal declaration of subroutine %s
2275
6903afa2 2276(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2277
a0d0e21e
LW
2278=item Illegal division by zero
2279
be771a83
GS
2280(F) You tried to divide a number by 0. Either something was wrong in
2281your logic, or you need to put a conditional in to guard against
2282meaningless input.
a0d0e21e 2283
6df41af2
GS
2284=item Illegal hexadecimal digit %s ignored
2285
be771a83
GS
2286(W digit) You may have tried to use a character other than 0 - 9 or
2287A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2288number stopped before the illegal character.
6df41af2 2289
a0d0e21e
LW
2290=item Illegal modulus zero
2291
be771a83
GS
2292(F) You tried to divide a number by 0 to get the remainder. Most
2293numbers don't take to this kindly.
a0d0e21e 2294
6df41af2 2295=item Illegal number of bits in vec
399388f4 2296
6df41af2
GS
2297(F) The number of bits in vec() (the third argument) must be a power of
2298two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2299
2300=item Illegal octal digit %s
a0d0e21e 2301
d1be9408 2302(F) You used an 8 or 9 in an octal number.
a0d0e21e 2303
399388f4 2304=item Illegal octal digit %s ignored
748a9306 2305
d1be9408 2306(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2307Interpretation of the octal number stopped before the 8 or 9.
748a9306 2308
e0e4a6e3 2309=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2310
675fa9ff 2311(F) You wrote something like
c608e803
KW
2312
2313 (?+foo)
2314
2315The C<"+"> is valid only when followed by digits, indicating a
2316capturing group. See
2317L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2318
375ed12a
JH
2319=item Illegal suidscript
2320
2321(F) The script run under suidperl was somehow illegal.
2322
fe13d51d 2323=item Illegal switch in PERL5OPT: -%c
6ff81951 2324
6df41af2 2325(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2326following switches: B<-[CDIMUdmtw]>.
6ff81951 2327
6df41af2 2328=item Ill-formed CRTL environ value "%s"
81e118e0 2329
75b44862 2330(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2331internal environ array, and encountered an element without the C<=>
2332delimiter used to separate keys from values. The element is ignored.
09bef843 2333
6df41af2 2334=item Ill-formed message in prime_env_iter: |%s|
54310121 2335
be771a83
GS
2336(W internal) A warning peculiar to VMS. Perl tried to read a logical
2337name or CLI symbol definition when preparing to iterate over %ENV, and
2338didn't see the expected delimiter between key and value, so the line was
2339ignored.
54310121 2340
6df41af2 2341=item (in cleanup) %s
9607fc9c 2342
be771a83
GS
2343(W misc) This prefix usually indicates that a DESTROY() method raised
2344the indicated exception. Since destructors are usually called by the
2345system at arbitrary points during execution, and often a vast number of
2346times, the warning is issued only once for any number of failures that
2347would otherwise result in the same message being repeated.
6df41af2 2348
be771a83
GS
2349Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2350also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2351
e0e4a6e3
FC
2352=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2353in m/%s/
0d0b4b3b 2354
675fa9ff 2355(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2356expression inside the construct was completely empty, or if there are
2357too many or few operands for the number of operators. Perl is not smart
2358enough to give you a more precise indication as to what is wrong.
2359
6fbc9859
MH
2360=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2361parent '%s'
2c7d6b9c
RGS
2362
2363(F) The method resolution order (MRO) of the given class is not
2364C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2365documentation in L<mro> for more information.
2366
979699d9
JH
2367=item In EBCDIC the v-string components cannot exceed 2147483647
2368
2369(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2370Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2371encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2372
6a2ed79a 2373=item Infinite recursion in regex
1a147d38
YO
2374
2375(F) You used a pattern that references itself without consuming any input
6903afa2 2376text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2377either consume text or fail.
2378
6dbe9451
NC
2379=item Initialization of state variables in list context currently forbidden
2380
6903afa2
FC
2381(F) Currently the implementation of "state" only permits the
2382initialization of scalar variables in scalar context. Re-write
2383C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2384context. Constructions such as C<state (@a) = foo()> will be
2385supported in a future perl release.
6dbe9451 2386
2186f873
FC
2387=item %%s[%s] in scalar context better written as $%s[%s]
2388
2389(W syntax) In scalar context, you've used an array index/value slice
2390(indicated by %) to select a single element of an array. Generally
2391it's better to ask for a scalar value (indicated by $). The difference
2392is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2393returns and when evaluating its argument, while C<%foo[&bar]> provides
2394a list context to its subscript, which can do weird things if you're
2395expecting only one subscript. When called in list context, it also
2396returns the index (what C<&bar> returns) in addition to the value.
2397
2398=item %%s{%s} in scalar context better written as $%s{%s}
2399
2400(W syntax) In scalar context, you've used a hash key/value slice
2401(indicated by %) to select a single element of a hash. Generally it's
2402better to ask for a scalar value (indicated by $). The difference
2403is that C<$foo{&bar}> always behaves like a scalar, both in the value
2404it returns and when evaluating its argument, while C<@foo{&bar}> and
2405provides a list context to its subscript, which can do weird things
2406if you're expecting only one subscript. When called in list context,
2407it also returns the key in addition to the value.
2408
a0d0e21e
LW
2409=item Insecure dependency in %s
2410
8b1a09fc 2411(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2412The tainting mechanism is turned on when you're running setuid or
2413setgid, or when you specify B<-T> to turn it on explicitly. The
2414tainting mechanism labels all data that's derived directly or indirectly
2415from the user, who is considered to be unworthy of your trust. If any
2416such data is used in a "dangerous" operation, you get this error. See
2417L<perlsec> for more information.
a0d0e21e
LW
2418
2419=item Insecure directory in %s
2420
be771a83
GS
2421(F) You can't use system(), exec(), or a piped open in a setuid or
2422setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2423the world. Also, the PATH must not contain any relative directory.
2424See L<perlsec>.
a0d0e21e 2425
62f468fc 2426=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2427
2428(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2429setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2430C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2431supplied (or potentially supplied) by the user. The script must set
2432the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2433
0e9be77f
DM
2434=item Insecure user-defined property %s
2435
2436(F) Perl detected tainted data when trying to compile a regular
2437expression that contains a call to a user-defined character property
2438function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2439See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2440
b9ef414d
FC
2441=item Integer overflow in format string for %s
2442
2443(F) The indexes and widths specified in the format string of C<printf()>
2444or C<sprintf()> are too large. The numbers must not overflow the size of
2445integers for your architecture.
2446
a7ae9550
GS
2447=item Integer overflow in %s number
2448
35928bc5 2449(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2450either as a literal or as an argument to hex() or oct() is too big for
2451your architecture, and has been converted to a floating point number.
2452On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2453representable without overflow is 0xFFFFFFFF, 037777777777, or
24540b11111111111111111111111111111111 respectively. Note that Perl
2455transparently promotes all numbers to a floating point representation
2456internally--subject to loss of precision errors in subsequent
2457operations.
bbce6d69 2458
fc89ca81
FC
2459=item Integer overflow in srand
2460
2461(S overflow) The number you have passed to srand is too big to fit
2462in your architecture's integer representation. The number has been
2463replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2464architectures). This means you may be getting less randomness than
2465you expect, because different random seeds above the maximum will
2466return the same sequence of random numbers.
2467
46314c13
JP
2468=item Integer overflow in version
2469
18da5252
FC
2470=item Integer overflow in version %d
2471
784d71ed
FC
2472(W overflow) Some portion of a version initialization is too large for
2473the size of integers for your architecture. This is not a warning
f084e84f 2474because there is no rational reason for a version to try and use an
784d71ed
FC
2475element larger than typically 2**32. This is usually caused by trying
2476to use some odd mathematical operation as a version, like 100/9.
46314c13 2477
e0e4a6e3 2478=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2479
2480(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2481The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2482discovered.
2483
748a9306
LW
2484=item Internal inconsistency in tracking vforks
2485
be771a83
GS
2486(S) A warning peculiar to VMS. Perl keeps track of the number of times
2487you've called C<fork> and C<exec>, to determine whether the current call
2488to C<exec> should affect the current script or a subprocess (see
2489L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2490Perl is making a guess and treating this C<exec> as a request to
2491terminate the Perl script and execute the specified command.
748a9306 2492
870978ae
FC
2493=item internal %<num>p might conflict with future printf extensions
2494
2495(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2496formatting follows a slightly different set of rules when called from
2497C or XS code. Specifically, formats consisting of digits followed
2498by "p" (e.g., "%7p") are reserved for future use. If you see this
2499message, then an XS module tried to call that routine with one such
2500reserved format.
2501
e0e4a6e3 2502=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2503
fa816bf3 2504(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2505S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2506discovered.
a0d0e21e 2507
6df41af2
GS
2508=item %s (...) interpreted as function
2509
75b44862 2510(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2511followed by parentheses turns into a function, with all the list
64977eb6 2512operators arguments found inside the parentheses. See
13a2d996 2513L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2514
f51551f7
FC
2515=item In '(?...)', the '(' and '?' must be adjacent in regex;
2516marked by S<<-- HERE> in m/%s/
2517
2518(F) The two-character sequence C<"(?"> in this context in a regular
2519expression pattern should be an indivisible token, with nothing
2520intervening between the C<"("> and the C<"?">, but you separated them
2521with whitespace.
2522
09bef843
SB
2523=item Invalid %s attribute: %s
2524
a4a4c9e2 2525(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2526by Perl or by a user-supplied handler. See L<attributes>.
2527
2528=item Invalid %s attributes: %s
2529
a4a4c9e2 2530(F) The indicated attributes for a subroutine or variable were not
be771a83 2531recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2532
e0e4a6e3
FC
2533=item Invalid character in charnames alias definition; marked by
2534S<<-- HERE> in '%s
225fb84f
KW
2535
2536(F) You tried to create a custom alias for a character name, with
2537the C<:alias> option to C<use charnames> and the specified character in
2538the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2539
c8028aa6
TC
2540=item Invalid \0 character in %s for %s: %s\0%s
2541
fa3234e3
FC
2542(W syscalls) Embedded \0 characters in pathnames or other system call
2543arguments produce a warning as of 5.20. The parts after the \0 were
2544formerly ignored by system calls.
c8028aa6 2545
e0e4a6e3 2546=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2547
2548(F) Only certain characters are valid for character names. The
2549indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2550
c635e13b
PP
2551=item Invalid conversion in %s: "%s"
2552
be771a83
GS
2553(W printf) Perl does not understand the given format conversion. See
2554L<perlfunc/sprintf>.
c635e13b 2555
e0e4a6e3
FC
2556=item Invalid escape in the specified encoding in regex; marked by
2557S<<-- HERE> in m/%s/
9e08bc66 2558
98d31c73 2559(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2560didn't correspond to a single character through the conversion
2561from the encoding specified by the encoding pragma.
98d31c73
FC
2562The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2563instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2564The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2565escape was discovered.
2566
8149aa9f
FC
2567=item Invalid hexadecimal number in \N{U+...}
2568
e0e4a6e3
FC
2569=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2570S<<-- HERE> in m/%s/
aec0ef10 2571
8149aa9f 2572(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2573number. Either it is empty, or you tried to use a character other than
25740 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2575
6651ba0b
FC
2576=item Invalid module name %s with -%c option: contains single ':'
2577
2578(F) The module argument to perl's B<-m> and B<-M> command-line options
2579cannot contain single colons in the module name, but only in the
2580arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2581B<-MFoo:Bar=baz> is not.
2582
2c7d6b9c
RGS
2583=item Invalid mro name: '%s'
2584
162a3e34
FC
2585(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2586where C<foo> is not a valid method resolution order (MRO). Currently,
2587the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2588a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2589
40e4140b
FC
2590=item Invalid negative number (%s) in chr
2591
2592(W utf8) You passed a negative number to C<chr>. Negative numbers are
2593not valid characters numbers, so it return the Unicode replacement
2594character (U+FFFD).
2595
6651ba0b
FC
2596=item invalid option -D%c, use -D'' to see choices
2597
8ff21bfe
FC
2598(S debugging) Perl was called with invalid debugger flags. Call perl
2599with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2600See also L<perlrun/-Dletters>.
6651ba0b 2601
e0e4a6e3 2602=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2603
2604(F) The range specified in a character class had a minimum character
7253e4e3
RK
2605greater than the maximum character. One possibility is that you forgot the
2606C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2607up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2608problem was discovered. See L<perlre>.
6df41af2 2609
d1573ac7 2610=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2611
2612(F) The range specified in the tr/// or y/// operator had a minimum
2613character greater than the maximum character. See L<perlop>.
2614
09bef843
SB
2615=item Invalid separator character %s in attribute list
2616
0120eecf 2617(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2618elements of an attribute list. If the previous attribute had a
2619parenthesised parameter list, perhaps that list was terminated too soon.
2620See L<attributes>.
09bef843 2621
b4581f09
JH
2622=item Invalid separator character %s in PerlIO layer specification %s
2623
2bfc5f71
FC
2624(W layer) When pushing layers onto the Perl I/O system, something other
2625than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2626If the previous attribute had a parenthesised parameter list, perhaps that
2627list was terminated too soon.
2628
2c86d456
DG
2629=item Invalid strict version format (%s)
2630
fa816bf3 2631(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2632A "strict" version number is a positive decimal number (integer or
2633decimal-fraction) without exponentiation or else a dotted-decimal
2634v-string with a leading 'v' character and at least three components.
a6485a24 2635The parenthesized text indicates which criteria were not met.
2c86d456
DG
2636See the L<version> module for more details on allowed version formats.
2637
49704364 2638=item Invalid type '%s' in %s
96e4d5b1 2639
49704364
LW
2640(F) The given character is not a valid pack or unpack type.
2641See L<perlfunc/pack>.
6728c851 2642
49704364 2643(W) The given character is not a valid pack or unpack type but used to be
75b44862 2644silently ignored.
96e4d5b1 2645
2c86d456
DG
2646=item Invalid version format (%s)
2647
fa816bf3 2648(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2649A "lax" version number is a positive decimal number (integer or
2650decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2651v-string. If the v-string has fewer than three components, it
2652must have a leading 'v' character. Otherwise, the leading 'v' is
2653optional. Both decimal and dotted-decimal versions may have a
2654trailing "alpha" component separated by an underscore character
2655after a fractional or dotted-decimal component. The parenthesized
2656text indicates which criteria were not met. See the L<version> module
2657for more details on allowed version formats.
46314c13 2658
798ae1b7
DG
2659=item Invalid version object
2660
fa816bf3
FC
2661(F) The internal structure of the version object was invalid.
2662Perhaps the internals were modified directly in some way or
2663an arbitrary reference was blessed into the "version" class.
798ae1b7 2664
cd209d9d 2665=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2666marked by S<<-- HERE> in m/%s/
675fa9ff 2667
cd209d9d 2668(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2669this context in a regular expression pattern should be an
2670indivisible token, with nothing intervening between the C<"(">
cd209d9d 2671and the C<"*">, but you separated them.
675fa9ff 2672
a0d0e21e
LW
2673=item ioctl is not implemented
2674
2675(F) Your machine apparently doesn't implement ioctl(), which is pretty
2676strange for a machine that supports C.
2677
c289d2f7
JH
2678=item ioctl() on unopened %s
2679
2680(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2681Check your control flow and number of arguments.
c289d2f7 2682
fe13d51d 2683=item IO layers (like '%s') unavailable
363c40c4
SB
2684
2685(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2686you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2687with 'useperlio'.
2688
80cbd5ad
JH
2689=item IO::Socket::atmark not implemented on this architecture
2690
2691(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2692neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2693
4f650b80 2694=item $* is no longer supported
b4581f09 2695
4f650b80 2696(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2697perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2698previous versions of perl the use of C<$*> enabled or disabled multi-line
2699matching within a string.
4fd19576
B
2700
2701Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2702modifiers. You can enable C</m> for a lexical scope (even a whole file)
2703with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2704then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2705
8ae1fe26
RGS
2706=item $# is no longer supported
2707
a58ac25e 2708(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2709perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2710should use the printf/sprintf functions instead.
8ae1fe26 2711
ccf3535a 2712=item '%s' is not a code reference
6ad11d81 2713
6903afa2
FC
2714(W overload) The second (fourth, sixth, ...) argument of
2715overload::constant needs to be a code reference. Either
2716an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2717
ccf3535a 2718=item '%s' is not an overloadable type
6ad11d81 2719
04a80ee0
RGS
2720(W overload) You tried to overload a constant type the overload package is
2721unaware of.
6ad11d81 2722
5a25739d
FC
2723=item -i used with no filenames on the command line, reading from STDIN
2724
2725(S inplace) The C<-i> option was passed on the command line, indicating
2726that the script is intended to edit files in place, but no files were
2727given. This is usually a mistake, since editing STDIN in place doesn't
2728make sense, and can be confusing because it can make perl look like
2729it is hanging when it is really just trying to read from STDIN. You
2730should either pass a filename to edit, or remove C<-i> from the command
2731line. See L<perlrun> for more details.
2732
aec0ef10 2733=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2734
2735(P) The regular expression parser is confused.
2736
0953b66b
FC
2737=item keys on reference is experimental
2738
0773cb3e
FC
2739(S experimental::autoderef) C<keys> with a scalar argument is experimental
2740and may change or be removed in a future Perl version. If you want to
2741take the risk of using this feature, simply disable this warning:
0953b66b 2742
d401967c 2743 no warnings "experimental::autoderef";
0953b66b 2744
a0d0e21e
LW
2745=item Label not found for "last %s"
2746
be771a83
GS
2747(F) You named a loop to break out of, but you're not currently in a loop
2748of that name, not even if you count where you were called from. See
2749L<perlfunc/last>.
a0d0e21e
LW
2750
2751=item Label not found for "next %s"
2752
2753(F) You named a loop to continue, but you're not currently in a loop of
2754that name, not even if you count where you were called from. See
2755L<perlfunc/last>.
2756
2757=item Label not found for "redo %s"
2758
2759(F) You named a loop to restart, but you're not currently in a loop of
2760that name, not even if you count where you were called from. See
2761L<perlfunc/last>.
2762
85ab1d1d 2763=item leaving effective %s failed
5ff3f7a4 2764
85ab1d1d 2765(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2766effective uids or gids failed.
2767
49704364
LW
2768=item length/code after end of string in unpack
2769
d7f8936a 2770(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2771length/code combination tried to obtain more data. This results in
2772an undefined value for the length. See L<perlfunc/pack>.
49704364 2773
25e26107 2774=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2775
0d46a4e7
FC
2776(W syntax) You used length() on either an array or a hash when you
2777probably wanted a count of the items.
e508c8a4
MH
2778
2779Array size can be obtained by doing:
2780
2781 scalar(@array);
2782
2783The number of items in a hash can be obtained by doing:
2784
2785 scalar(keys %hash);
2786
f0e67a1d
Z
2787=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2788
d4fe7078
RS
2789(F) An extension is attempting to insert text into the current parse
2790(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2791couldn't be part of the current input. This is an inherent pitfall
2792of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2793it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2794
2795=item Lexing code internal error (%s)
2796
2797(F) Lexing code supplied by an extension violated the lexer's API in a
2798detectable way.
2799
69282e91 2800=item listen() on closed socket %s
a0d0e21e 2801
be771a83
GS
2802(W closed) You tried to do a listen on a closed socket. Did you forget
2803to check the return value of your socket() call? See
2804L<perlfunc/listen>.
a0d0e21e 2805
6651ba0b
FC
2806=item List form of piped open not implemented
2807
2808(F) On some platforms, notably Windows, the three-or-more-arguments
2809form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2810Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2811
b35b96b6
JH
2812=item localtime(%f) failed
2813
2814(W overflow) You called C<localtime> with a number that it could not handle:
2815too large, too small, or NaN. The returned value is C<undef>.
2816
bcd05b94 2817=item localtime(%f) too large
8b56d6ff 2818
e9200be3 2819(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2820than it can reliably handle and C<localtime> probably returned the
6903afa2 2821wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2822not-a-number value).
2823
bcd05b94 2824=item localtime(%f) too small
fc003d4b 2825
e9200be3 2826(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2827than it can reliably handle and C<localtime> probably returned the
e7a1a147 2828wrong date.
8b56d6ff 2829
58e23c8d 2830=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2831
2832(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2833handle. This restriction may be eased in a future release.
2e50fd82 2834
b88df990
NC
2835=item Lost precision when %s %f by 1
2836
e63e8a91
FC
2837(W imprecision) The value you attempted to increment or decrement by one
2838is too large for the underlying floating point representation to store
2839accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2840warning because it has already switched from integers to floating point
2841when values are too large for integers, and now even floating point is
2842insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2843
93fad930 2844=item lstat() on filehandle%s
2f7da168
RK
2845
2846(W io) You tried to do an lstat on a filehandle. What did you mean
2847by that? lstat() makes sense only on filenames. (Perl did a fstat()
2848instead on the filehandle.)
2849
345d70e3 2850=item lvalue attribute %s already-defined subroutine
bb3abb05 2851
345d70e3
FC
2852(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2853attribute on or off on a Perl subroutine that is already defined
2854does not always work properly. It may or may not do what you
2855want, depending on what code is inside the subroutine, with exact
2856details subject to change between Perl versions. Only do this
2857if you really know what you are doing.
bb3abb05 2858
885ef6f5
GG
2859=item lvalue attribute ignored after the subroutine has been defined
2860
345d70e3
FC
2861(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2862subroutine an lvalue subroutine after it has been defined is
2863not permitted. To make the subroutine an lvalue subroutine,
2864add the lvalue attribute to the definition, or put the C<sub
2865foo :lvalue;> declaration before the definition.
2866
2867See also L<attributes.pm|attributes>.
885ef6f5 2868
6f1b3ab0
FC
2869=item Magical list constants are not supported
2870
2871(F) You assigned a magical array to a stash element, and then tried
2872to use the subroutine from the same slot. You are asking Perl to do
2873something it cannot do, details subject to change between Perl versions.
2874
2db62bbc 2875=item Malformed integer in [] in pack
49704364 2876
2db62bbc 2877(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2878are permitted. See L<perlfunc/pack>.
2879
2880=item Malformed integer in [] in unpack
2881
2db62bbc 2882(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2883are permitted. See L<perlfunc/pack>.
2884
6df41af2
GS
2885=item Malformed PERLLIB_PREFIX
2886
2887(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2888
2889 prefix1;prefix2
2890
2891or
6df41af2
GS
2892 prefix1 prefix2
2893
be771a83
GS
2894with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2895a builtin library search path, prefix2 is substituted. The error may
2896appear if components are not found, or are too long. See
fecfaeb8 2897"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2898
2f758a16
ST
2899=item Malformed prototype for %s: %s
2900
d37a9538
ST
2901(F) You tried to use a function with a malformed prototype. The
2902syntax of function prototypes is given a brief compile-time check for
2903obvious errors like invalid characters. A more rigorous check is run
2904when the function is called.
30d9c59b
Z
2905Perhaps the function's author was trying to write a subroutine signature
2906but didn't enable that feature first (C<use feature 'signatures'>),
2907so the signature was instead interpreted as a bad prototype.
2f758a16 2908
ba210ebe
JH
2909=item Malformed UTF-8 character (%s)
2910
4d6f11e5 2911(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2912encoding rules, even though it had the UTF8 flag on.
ba210ebe 2913
2575c402
JW
2914One possible cause is that you set the UTF8 flag yourself for data that
2915you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 29168-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2917
2918If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2919sequences are handled gracefully, but if you use C<:utf8>, the flag is
2920set without validating the data, possibly resulting in this error
2921message.
2922
2923See also L<Encode/"Handling Malformed Data">.
901b21bf 2924
107160e2
KW
2925=item Malformed UTF-8 character immediately after '%s'
2926
2927(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2928encoding rules. The message prints out the properly encoded characters
2929just before the first bad one. If C<utf8> warnings are enabled, a
2930warning is generated that gives more details about the type of
2931malformation.
2932
bde9e88d 2933=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2934
2935(F) The charnames handler returned malformed UTF-8.
2936
4a5d3a93
FC
2937=item Malformed UTF-8 string in '%c' format in unpack
2938
2939(F) You tried to unpack something that didn't comply with UTF-8 encoding
2940rules and perl was unable to guess how to make more progress.
2941
f337b084
TH
2942=item Malformed UTF-8 string in pack
2943
2944(F) You tried to pack something that didn't comply with UTF-8 encoding
2945rules and perl was unable to guess how to make more progress.
2946
2947=item Malformed UTF-8 string in unpack
2948
2949(F) You tried to unpack something that didn't comply with UTF-8 encoding
2950rules and perl was unable to guess how to make more progress.
2951
4a5d3a93 2952=item Malformed UTF-16 surrogate
f337b084 2953
4a5d3a93
FC
2954(F) Perl thought it was reading UTF-16 encoded character data but while
2955doing it Perl met a malformed Unicode surrogate.
2956
30d9c59b
Z
2957=item Mandatory parameter follows optional parameter
2958
2959(F) In a subroutine signature, you wrote something like "$a = undef,
2960$b", making an earlier parameter optional and a later one mandatory.
2961Parameters are filled from left to right, so it's impossible for the
2962caller to omit an earlier one and pass a later one. If you want to act
2963as if the parameters are filled from right to left, declare the rightmost
2964optional and then shuffle the parameters around in the subroutine's body.
2965
2d88a86a
KW
2966=item Matched non-Unicode code point 0x%X against Unicode property; may
2967not be portable
2968
2969(S non_unicode) Perl allows strings to contain a superset of
2970Unicode code points; each code point may be as large as what is storable
2971in an unsigned integer on your system, but these may not be accepted by
2972other languages/systems. This message occurs when you matched a string
2973containing such a code point against a regular expression pattern, and
2974the code point was matched against a Unicode property, C<\p{...}> or
2975C<\P{...}>. Unicode properties are only defined on Unicode code points,
2976so the result of this match is undefined by Unicode, but Perl (starting
2977in v5.20) treats non-Unicode code points as if they were typical
2978unassigned Unicode ones, and matched this one accordingly. Whether a
2979given property matches these code points or not is specified in
2980L<perluniprops/Properties accessible through \p{} and \P{}>.
2981
2982This message is suppressed (unless it has been made fatal) if it is
2983immaterial to the results of the match if the code point is Unicode or
2984not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2985the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2986Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2987every code point except these 22.)
2988
2989Getting this message indicates that the outcome of the match arguably
2990should have been the opposite of what actually happened. If you think
2991that is the case, you may wish to make the C<non_unicode> warnings
2992category fatal; if you agree with Perl's decision, you may wish to turn
2993off this category.
2994
2995See L<perlunicode/Beyond Unicode code points> for more information.
2996
e0e4a6e3
FC
2997=item %s matches null string many times in regex; marked by S<<-- HERE> in
2998m/%s/
4a5d3a93
FC
2999
3000(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3001regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3002shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3003See L<perlre>.
f337b084 3004
de42a5a9 3005=item Maximal count of pending signals (%u) exceeded
2563cec5 3006
6903afa2 3007(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3008usually indicates that your operating system tried to deliver signals
3009too fast (with a very high priority), starving the perl process from
3010resources it would need to reach a point where it can process signals
6903afa2 3011safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3012
25f58aea
PN
3013=item "%s" may clash with future reserved word
3014
3015(W) This warning may be due to running a perl5 script through a perl4
3016interpreter, especially if the word that is being warned about is
3017"use" or "my".
3018
0d2487cd 3019=item '%' may not be used in pack
6df41af2
GS
3020
3021(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3022checksumming process loses information, and you can't go the other way.
3023See L<perlfunc/unpack>.
6df41af2 3024
a0d0e21e
LW
3025=item Method for operation %s not found in package %s during blessing
3026
3027(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3028doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3029
3cdd684c
TP
3030=item Method %s not permitted
3031
3032See Server error.
3033
a0d0e21e
LW
3034=item Might be a runaway multi-line %s string starting on line %d
3035
3036(S) An advisory indicating that the previous error may have been caused
3037by a missing delimiter on a string or pattern, because it eventually
3038ended earlier on the current line.
3039
3040=item Misplaced _ in number
3041
d4ced10d
JH
3042(W syntax) An underscore (underbar) in a numeric constant did not
3043separate two digits.
a0d0e21e 3044
7baa4690
HS
3045=item Missing argument in %s
3046
3664866e
AB
3047(W missing) You called a function with fewer arguments than other
3048arguments you supplied indicated would be needed.
3049
3050Currently only emitted when a printf-type format required more
3051arguments than were supplied, but might be used in the future for
3052other cases where we can statically determine that arguments to
3053functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3054
9e81e6a1
RGS
3055=item Missing argument to -%c
3056
3057(F) The argument to the indicated command line switch must follow
3058immediately after the switch, without intervening spaces.
3059
ff3f963a 3060=item Missing braces on \N{}
423cee85 3061
e0e4a6e3 3062=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3063
4a2d328f 3064(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3065double-quotish context. This can also happen when there is a space
3066(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3067This modifier does not change the requirement that the brace immediately
3068follow the C<\N>.
423cee85 3069
f0a2b745
KW
3070=item Missing braces on \o{}
3071
3072(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3073
a0d0e21e
LW
3074=item Missing comma after first argument to %s function
3075
3076(F) While certain functions allow you to specify a filehandle or an
3077"indirect object" before the argument list, this ain't one of them.
3078
06eaf0bc
GS
3079=item Missing command in piped open
3080
be771a83
GS
3081(W pipe) You used the C<open(FH, "| command")> or
3082C<open(FH, "command |")> construction, but the command was missing or
3083blank.
06eaf0bc 3084
961ce445
RGS
3085=item Missing control char name in \c
3086
3087(F) A double-quoted string ended with "\c", without the required control
3088character name.
3089
591f5ca2
FC
3090=item Missing ']' in prototype for %s : %s
3091
bfe11873 3092(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3093
8767b1ab 3094=item Missing name in "%s sub"
6df41af2 3095
87444db5 3096(F) The syntax for lexically scoped subroutines requires that
be771a83 3097they have a name with which they can be found.
6df41af2
GS
3098
3099=item Missing $ on loop variable
3100
be771a83
GS
3101(F) Apparently you've been programming in B<csh> too much. Variables
3102are always mentioned with the $ in Perl, unlike in the shells, where it
3103can vary from one line to the next.
6df41af2 3104
cc507455 3105=item (Missing operator before %s?)
748a9306 3106
56da5a46
RGS
3107(S syntax) This is an educated guess made in conjunction with the message
3108"%s found where operator expected". Often the missing operator is a comma.
748a9306 3109
f51551f7
FC
3110=item Missing or undefined argument to require
3111
3112(F) You tried to call require with no argument or with an undefined
3113value as an argument. Require expects either a package name or a
3114file-specification as an argument. See L<perlfunc/require>.
3115
e0e4a6e3 3116=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3117
ff3f963a
KW
3118(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3119
4a68bf9d 3120=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3121
d32207c9
FC
3122(F) C<\N> has two meanings.
3123
3124The traditional one has it followed by a name enclosed in braces,
3125meaning the character (or sequence of characters) given by that
fa816bf3 3126name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3127double-quoted strings and regular expression patterns. In patterns,
3128it doesn't have the meaning an unescaped C<*> does.
3129
3130Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3131in patterns, namely to match a non-newline character. (This is short
3132for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3133
3134This can lead to some ambiguities. When C<\N> is not followed immediately
3135by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3136form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3137means to match the given quantity of non-newlines (in these examples,
31383; and 5 or more, respectively). In all other case, where there is a
3139C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3140
3141However, if there is no matching C<}>, Perl doesn't know if it was
3142mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3143If you meant the former, add the right brace; if you meant the latter,
3144escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3145
d98d5fff 3146=item Missing right curly or square bracket
a0d0e21e 3147
be771a83
GS
3148(F) The lexer counted more opening curly or square brackets than closing
3149ones. As a general rule, you'll find it's missing near the place you
3150were last editing.
a0d0e21e 3151
6df41af2
GS
3152=item (Missing semicolon on previous line?)
3153
56da5a46
RGS
3154(S syntax) This is an educated guess made in conjunction with the message
3155"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3156the previous line just because you saw this message.
3157
a0d0e21e
LW
3158=item Modification of a read-only value attempted
3159
3160(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3161constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3162catches that. But an easy way to do the same thing is:
3163
3164 sub mod { $_[0] = 1 }
3165 mod(2);
3166
3167Another way is to assign to a substr() that's off the end of the string.
3168
c5674021
PDF
3169Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3170is aliased to a constant in the look I<LIST>:
3171
b7e4ecc1
FC
3172 $x = 1;
3173 foreach my $n ($x, 2) {
3174 $n *= 2; # modifies the $x, but fails on attempt to
3175 } # modify the 2
c5674021 3176
7a4340ed 3177=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3178
3179(F) You tried to make an array value spring into existence, and the
3180subscript was probably negative, even counting from end of the array
3181backwards.
3182
7a4340ed 3183=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3184
be771a83
GS
3185(P) You tried to make a hash value spring into existence, and it
3186couldn't be created for some peculiar reason.
a0d0e21e
LW
3187
3188=item Module name must be constant
3189
3190(F) Only a bare module name is allowed as the first argument to a "use".
3191
be98fb35 3192=item Module name required with -%c option
6df41af2 3193
be98fb35
GS
3194(F) The C<-M> or C<-m> options say that Perl should load some module, but
3195you omitted the name of the module. Consult L<perlrun> for full details
3196about C<-M> and C<-m>.
6df41af2 3197
fe13d51d 3198=item More than one argument to '%s' open
ed9aa3b7 3199
6903afa2 3200(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3201can happen if you are trying to open a pipe to a command that takes a
3202list of arguments, but have forgotten to specify a piped open mode.
3203See L<perlfunc/open> for details.
3204
85396b18
FC
3205=item mprotect for COW string %p %u failed with %d
3206
3207(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3208L<perlguts/"Copy on Write">), but a shared string buffer
3209could not be made read-only.
3210
92951bce
FC
3211=item mprotect for %p %u failed with %d
3212
85396b18
FC
3213(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3214but an op tree could not be made read-only.
3215
3216=item mprotect RW for COW string %p %u failed with %d
3217
3218(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3219L<perlguts/"Copy on Write">), but a read-only shared string
3220buffer could not be made mutable.
3221
92951bce
FC
3222=item mprotect RW for %p %u failed with %d
3223
3224(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3225L<perlhacktips>), but a read-only op tree could not be made
3226mutable before freeing the ops.
92951bce 3227
a0d0e21e
LW
3228=item msg%s not implemented
3229
3230(F) You don't have System V message IPC on your system.
3231
3232=item Multidimensional syntax %s not supported
3233
75b44862
GS
3234(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3235They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3236
49704364 3237=item '/' must follow a numeric type in unpack
6df41af2 3238
49704364
LW
3239(F) You had an unpack template that contained a '/', but this did not
3240follow some unpack specification producing a numeric value.
3241See L<perlfunc/pack>.
6df41af2
GS
3242
3243=item "my sub" not yet implemented
3244
be771a83
GS
3245(F) Lexically scoped subroutines are not yet implemented. Don't try
3246that yet.
6df41af2 3247
5a25739d
FC
3248=item "my %s" used in sort comparison
3249
3250(W syntax) The package variables $a and $b are used for sort comparisons.
3251You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3252sort comparison block, and the variable had earlier been declared as a
3253lexical variable. Either qualify the sort variable with the package
3254name, or rename the lexical variable.
3255
fd1b7234 3256=item "my" variable %s can't be in a package
6df41af2 3257
be771a83
GS
3258(F) Lexically scoped variables aren't in a package, so it doesn't make
3259sense to try to declare one with a package qualifier on the front. Use
3260local() if you want to localize a package variable.
09bef843 3261
8149aa9f
FC
3262=item Name "%s::%s" used only once: possible typo
3263
c59aba6c
FC
3264(W once) Typographical errors often show up as unique variable
3265names. If you had a good reason for having a unique name, then
3266just mention it again somehow to suppress the message. The C<our>
08a33b6b 3267declaration is also provided for this purpose.
c59aba6c 3268
66a1f5ec
FC
3269NOTE: This warning detects package symbols that have been used
3270only once. This means lexical variables will never trigger this
3271warning. It also means that all of the package variables $c, @c,
3272%c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3273format) are considered the same; if a program uses $c only once
3274but also uses any of the others it will not trigger this warning.
3275Symbols beginning with an underscore and symbols using special
3276identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3277
e0e4a6e3 3278=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3279
3280(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3281exactly 3 digits long. This helps catch some ambiguities. If your
3282constant is too short, add leading zeros, like
3283
3284 (?[ [ \078 ] ]) # Syntax error!
3285 (?[ [ \0078 ] ]) # Works
3286 (?[ [ \007 8 ] ]) # Clearer
3287
3288The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3289need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3290two separate things, you need to separate them:
0d0b4b3b
KW
3291
3292 (?[ [ \7776 ] ]) # Syntax error!
3293 (?[ [ \o{7776} ] ]) # One meaning
3294 (?[ [ \777 6 ] ]) # Another meaning
3295 (?[ [ \777 \006 ] ]) # Still another
3296
49704364
LW
3297=item Negative '/' count in unpack
3298
3299(F) The length count obtained from a length/code unpack operation was
3300negative. See L<perlfunc/pack>.
3301
a0d0e21e
LW
3302=item Negative length
3303
be771a83
GS
3304(F) You tried to do a read/write/send/recv operation with a buffer
3305length that is less than 0. This is difficult to imagine.
a0d0e21e 3306
ed9aa3b7
SG
3307=item Negative offset to vec in lvalue context
3308
3309(F) When C<vec> is called in an lvalue context, the second argument must be
3310greater than or equal to zero.
3311
b3211734
KW
3312=item Negative repeat count does nothing
3313
3314(W numeric) You tried to execute the
3315L<C<x>|perlop/Multiplicative Operators> repetition operator fewer than 0
3316times, which doesn't make sense.
3317
e0e4a6e3 3318=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3319
6903afa2 3320(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3321So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3322whereabouts in the regular expression the problem was discovered.
a0d0e21e 3323
7253e4e3