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perldiag: rewrap for better splain output; clarifications
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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
6df41af2
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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
1109a392
MHM
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
2d8eb851 196=item charnames alias definitions may not contain a sequence of multiple spaces
bd299e29 197
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198(F) You defined a character name which had multiple space characters
199in a row. Change them to single spaces. Usually these names are
200defined in the C<:alias> import argument to C<use charnames>, but they
201could be defined by a translator installed into C<$^H{charnames}>. See
202L<charnames/CUSTOM ALIASES>.
bd299e29 203
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KW
204=item charnames alias definitions may not contain trailing white-space
205
206(F) You defined a character name which ended in a space
207character. Remove the trailing space(s). Usually these names are
208defined in the C<:alias> import argument to C<use charnames>, but they
209could be defined by a translator installed into C<$^H{charnames}>.
210See L<charnames/CUSTOM ALIASES>.
211
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212=item assertion botched: %s
213
21b5e840 214(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 215
0eacef8e 216=item Assertion %s failed: file "%s", line %d
a0d0e21e 217
21b5e840 218(X) A general assertion failed. The file in question must be examined.
a0d0e21e 219
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220=item Assigning non-zero to $[ is no longer possible
221
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222(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
223the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 224
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225=item Assignment to both a list and a scalar
226
227(F) If you assign to a conditional operator, the 2nd and 3rd arguments
228must either both be scalars or both be lists. Otherwise Perl won't
229know which context to supply to the right side.
230
2393f1b9 231=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 232
49293501 233(F) The failing code has attempted to get or set a key which is not in
2393f1b9 234the current set of allowed keys of a restricted hash.
49293501 235
dcdfe746
FC
236=item Attempt to bless into a freed package
237
238(F) You wrote C<bless $foo> with one argument after somehow causing
239the current package to be freed. Perl cannot figure out what to
240do, so it throws up in hands in despair.
241
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242=item Attempt to bless into a reference
243
244(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 245the name of the package to bless the resulting object into. You've
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246supplied instead a reference to something: perhaps you wrote
247
248 bless $self, $proto;
249
250when you intended
251
252 bless $self, ref($proto) || $proto;
253
254If you actually want to bless into the stringified version
255of the reference supplied, you need to stringify it yourself, for
256example by:
257
258 bless $self, "$proto";
259
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260=item Attempt to clear deleted array
261
262(S debugging) An array was assigned to when it was being freed.
263Freed values are not supposed to be visible to Perl code. This
264can also happen if XS code calls C<av_clear> from a custom magic
265callback on the array.
266
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267=item Attempt to delete disallowed key '%s' from a restricted hash
268
269(F) The failing code attempted to delete from a restricted hash a key
270which is not in its key set.
271
272=item Attempt to delete readonly key '%s' from a restricted hash
273
274(F) The failing code attempted to delete a key whose value has been
275declared readonly from a restricted hash.
276
de42a5a9 277=item Attempt to free non-arena SV: 0x%x
a0d0e21e 278
f84fe999 279(S internal) All SV objects are supposed to be allocated from arenas
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280that will be garbage collected on exit. An SV was discovered to be
281outside any of those arenas.
a0d0e21e 282
12578ffb 283=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 284
f84fe999 285(S internal) Perl maintains a reference-counted internal table of
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286strings to optimize the storage and access of hash keys and other
287strings. This indicates someone tried to decrement the reference count
288of a string that can no longer be found in the table.
bbce6d69 289
7d5b40b4 290=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 291
f84fe999 292(S debugging) Mortalized values are supposed to be freed by the
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293free_tmps() routine. This indicates that something else is freeing the
294SV before the free_tmps() routine gets a chance, which means that the
295free_tmps() routine will be freeing an unreferenced scalar when it does
296try to free it.
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297
298=item Attempt to free unreferenced glob pointers
299
f84fe999 300(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 301
7d5b40b4 302=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 303
8f7e4d2c 304(S internal) Perl went to decrement the reference count of a scalar to
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305see if it would go to 0, and discovered that it had already gone to 0
306earlier, and should have been freed, and in fact, probably was freed.
307This could indicate that SvREFCNT_dec() was called too many times, or
308that SvREFCNT_inc() was called too few times, or that the SV was
309mortalized when it shouldn't have been, or that memory has been
310corrupted.
a0d0e21e 311
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312=item Attempt to pack pointer to temporary value
313
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314(W pack) You tried to pass a temporary value (like the result of a
315function, or a computed expression) to the "p" pack() template. This
316means the result contains a pointer to a location that could become
317invalid anytime, even before the end of the current statement. Use
318literals or global values as arguments to the "p" pack() template to
319avoid this warning.
84902520 320
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321=item Attempt to reload %s aborted.
322
323(F) You tried to load a file with C<use> or C<require> that failed to
324compile once already. Perl will not try to compile this file again
325unless you delete its entry from %INC. See L<perlfunc/require> and
326L<perlvar/%INC>.
327
1b20cd17
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328=item Attempt to set length of freed array
329
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330(W misc) You tried to set the length of an array which has
331been freed. You can do this by storing a reference to the
332scalar representing the last index of an array and later
333assigning through that reference. For example
1b20cd17
NC
334
335 $r = do {my @a; \$#a};
336 $$r = 503
337
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338=item Attempt to use reference as lvalue in substr
339
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340(W substr) You supplied a reference as the first argument to substr()
341used as an lvalue, which is pretty strange. Perhaps you forgot to
342dereference it first. See L<perlfunc/substr>.
b7a902f4 343
c32124fe
NC
344=item Attribute "locked" is deprecated
345
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FC
346(D deprecated) You have used the attributes pragma to modify the
347"locked" attribute on a code reference. The :locked attribute is
348obsolete, has had no effect since 5005 threads were removed, and
349will be removed in a future release of Perl 5.
c32124fe 350
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FC
351=item Attribute prototype(%s) discards earlier prototype attribute in same sub
352
353(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
354example. Since each sub can only have one prototype, the earlier
355declaration(s) are discarded while the last one is applied.
356
f1a3ce43
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357=item Attribute "unique" is deprecated
358
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FC
359(D deprecated) You have used the attributes pragma to modify
360the "unique" attribute on an array, hash or scalar reference.
361The :unique attribute has had no effect since Perl 5.8.8, and
362will be removed in a future release of Perl 5.
f1a3ce43 363
ccce04a4
FC
364=item av_reify called on tied array
365
366(S debugging) This indicates that something went wrong and Perl got I<very>
367confused about C<@_> or C<@DB::args> being tied.
368
de42a5a9 369=item Bad arg length for %s, is %u, should be %d
a0d0e21e 370
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371(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
372or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 373S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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374S<sizeof(struct shmid_ds *)>.
375
7a95317d
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376=item Bad evalled substitution pattern
377
496a33f5 378(F) You've used the C</e> switch to evaluate the replacement for a
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379substitution, but perl found a syntax error in the code to evaluate,
380most likely an unexpected right brace '}'.
381
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382=item Bad filehandle: %s
383
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384(F) A symbol was passed to something wanting a filehandle, but the
385symbol has no filehandle associated with it. Perhaps you didn't do an
386open(), or did it in another package.
a0d0e21e
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387
388=item Bad free() ignored
389
be771a83 390(S malloc) An internal routine called free() on something that had never
fa816bf3 391been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 392setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 393
9ea8bc6d 394This message can be seen quite often with DB_File on systems with "hard"
6903afa2 395dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 396which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 397
aa689395
PP
398=item Bad hash
399
400(P) One of the internal hash routines was passed a null HV pointer.
401
6df41af2
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402=item Badly placed ()'s
403
404(A) You've accidentally run your script through B<csh> instead
405of Perl. Check the #! line, or manually feed your script into
406Perl yourself.
407
a7cb8dae 408=item Bad name after %s
a0d0e21e 409
be771a83
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410(F) You started to name a symbol by using a package prefix, and then
411didn't finish the symbol. In particular, you can't interpolate outside
412of quotes, so
a0d0e21e
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413
414 $var = 'myvar';
415 $sym = mypack::$var;
416
417is not the same as
418
419 $var = 'myvar';
420 $sym = "mypack::$var";
421
88e1f1a2
JV
422=item Bad plugin affecting keyword '%s'
423
424(F) An extension using the keyword plugin mechanism violated the
425plugin API.
426
4ad56ec9
IZ
427=item Bad realloc() ignored
428
6903afa2
FC
429(S malloc) An internal routine called realloc() on something that
430had never been malloc()ed in the first place. Mandatory, but can
431be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 432
a0d0e21e
LW
433=item Bad symbol for array
434
435(P) An internal request asked to add an array entry to something that
436wasn't a symbol table entry.
437
4df3f177
SP
438=item Bad symbol for dirhandle
439
440(P) An internal request asked to add a dirhandle entry to something
441that wasn't a symbol table entry.
442
a0d0e21e
LW
443=item Bad symbol for filehandle
444
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445(P) An internal request asked to add a filehandle entry to something
446that wasn't a symbol table entry.
a0d0e21e
LW
447
448=item Bad symbol for hash
449
450(P) An internal request asked to add a hash entry to something that
451wasn't a symbol table entry.
452
34d09196
GS
453=item Bareword found in conditional
454
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455(W bareword) The compiler found a bareword where it expected a
456conditional, which often indicates that an || or && was parsed as part
457of the last argument of the previous construct, for example:
34d09196
GS
458
459 open FOO || die;
460
be771a83
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461It may also indicate a misspelled constant that has been interpreted as
462a bareword:
34d09196
GS
463
464 use constant TYPO => 1;
465 if (TYOP) { print "foo" }
466
467The C<strict> pragma is useful in avoiding such errors.
468
6df41af2
GS
469=item Bareword "%s" not allowed while "strict subs" in use
470
471(F) With "strict subs" in use, a bareword is only allowed as a
be771a83
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472subroutine identifier, in curly brackets or to the left of the "=>"
473symbol. Perhaps you need to predeclare a subroutine?
6df41af2
GS
474
475=item Bareword "%s" refers to nonexistent package
476
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477(W bareword) You used a qualified bareword of the form C<Foo::>, but the
478compiler saw no other uses of that namespace before that point. Perhaps
479you need to predeclare a package?
6df41af2 480
a0d0e21e
LW
481=item BEGIN failed--compilation aborted
482
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483(F) An untrapped exception was raised while executing a BEGIN
484subroutine. Compilation stops immediately and the interpreter is
485exited.
a0d0e21e 486
68dc0745
PP
487=item BEGIN not safe after errors--compilation aborted
488
489(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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490implies a C<BEGIN {}>) after one or more compilation errors had already
491occurred. Since the intended environment for the C<BEGIN {}> could not
492be guaranteed (due to the errors), and since subsequent code likely
493depends on its correct operation, Perl just gave up.
68dc0745 494
c782d7ee 495=item \%d better written as $%d
6df41af2 496
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497(W syntax) Outside of patterns, backreferences live on as variables.
498The use of backslashes is grandfathered on the right-hand side of a
499substitution, but stylistically it's better to use the variable form
500because other Perl programmers will expect it, and it works better if
501there are more than 9 backreferences.
6df41af2 502
252aa082
JH
503=item Binary number > 0b11111111111111111111111111111111 non-portable
504
e476b1b5 505(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
506(4294967295) and therefore non-portable between systems. See
507L<perlport> for more on portability concerns.
252aa082 508
69282e91 509=item bind() on closed socket %s
a0d0e21e 510
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511(W closed) You tried to do a bind on a closed socket. Did you forget to
512check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 513
c289d2f7
JH
514=item binmode() on closed filehandle %s
515
516(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 517Check your control flow and number of arguments.
c289d2f7 518
c5a0f51a
JH
519=item Bit vector size > 32 non-portable
520
e476b1b5 521(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 522
043c750c 523=item Bizarre copy of %s
4633a7c4 524
be771a83 525(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 526copiable.
4633a7c4 527
5a25739d
FC
528=item Bizarre SvTYPE [%d]
529
434f489b 530(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
531encountered an invalid data type.
532
f675dbe5
CB
533=item Buffer overflow in prime_env_iter: %s
534
be771a83
GS
535(W internal) A warning peculiar to VMS. While Perl was preparing to
536iterate over %ENV, it encountered a logical name or symbol definition
537which was too long, so it was truncated to the string shown.
f675dbe5 538
0f2d6309
DM
539=item \C is deprecated in regex; marked by <-- HERE in m/%s/
540
541(D deprecated, regexp) The \C character class is deprecated, and will
542become a compile-time error in a future release of perl (tentatively
543v5.24). This construct allows you to match a single byte of what makes up
544a multi-byte single UTF8 character, and breaks encapsulation. It is
545currently also very buggy. If you really need to process the individual
546bytes, you probably want to convert your string to one where each
547underlying byte is stored as a character, with utf8::encode().
548
a0d0e21e
LW
549=item Callback called exit
550
4929bf7b 551(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
552exited by calling exit.
553
6df41af2 554=item %s() called too early to check prototype
f675dbe5 555
be771a83
GS
556(W prototype) You've called a function that has a prototype before the
557parser saw a definition or declaration for it, and Perl could not check
558that the call conforms to the prototype. You need to either add an
559early prototype declaration for the subroutine in question, or move the
560subroutine definition ahead of the call to get proper prototype
561checking. Alternatively, if you are certain that you're calling the
562function correctly, you may put an ampersand before the name to avoid
563the warning. See L<perlsub>.
f675dbe5 564
56feebad
FC
565=item Calling POSIX::%s() is deprecated
566
567(D deprecated) You called a function whose use is deprecated. See
568the function's name in L<POSIX> for details.
569
49704364 570=item Cannot compress integer in pack
0258719b
NC
571
572(F) An argument to pack("w",...) was too large to compress. The BER
573compressed integer format can only be used with positive integers, and you
574attempted to compress Infinity or a very large number (> 1e308).
575See L<perlfunc/pack>.
576
49704364 577=item Cannot compress negative numbers in pack
0258719b
NC
578
579(F) An argument to pack("w",...) was negative. The BER compressed integer
580format can only be used with positive integers. See L<perlfunc/pack>.
581
5c1f4d79
NC
582=item Cannot convert a reference to %s to typeglob
583
6903afa2
FC
584(F) You manipulated Perl's symbol table directly, stored a reference
585in it, then tried to access that symbol via conventional Perl syntax.
586The access triggers Perl to autovivify that typeglob, but it there is
587no legal conversion from that type of reference to a typeglob.
5c1f4d79 588
4040665a 589=item Cannot copy to %s
ba2fdce6
NC
590
591(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 592be directly assigned to.
ba2fdce6 593
b5d97229
RGS
594=item Cannot find encoding "%s"
595
596(S io) You tried to apply an encoding that did not exist to a filehandle,
597either with open() or binmode().
598
7355df7e
FC
599=item Cannot set tied @DB::args
600
601(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
602is not supported. (Before this error was added, it used to crash.)
603
ce65bc73
FC
604=item Cannot tie unreifiable array
605
606(P) You somehow managed to call C<tie> on an array that does not
607keep a reference count on its arguments and cannot be made to
608do so. Such arrays are not even supposed to be accessible to
609Perl code, but are only used internally.
610
96ebfdd7
RK
611=item Can only compress unsigned integers in pack
612
613(F) An argument to pack("w",...) was not an integer. The BER compressed
614integer format can only be used with positive integers, and you attempted
615to compress something else. See L<perlfunc/pack>.
616
a0d0e21e
LW
617=item Can't bless non-reference value
618
619(F) Only hard references may be blessed. This is how Perl "enforces"
620encapsulation of objects. See L<perlobj>.
621
dc57907a
RGS
622=item Can't "break" in a loop topicalizer
623
0d863452 624(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 625a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
626
627=item Can't "break" outside a given block
dc57907a 628
0d863452
RH
629(F) You called C<break>, but you're not inside a C<given> block.
630
6df41af2
GS
631=item Can't call method "%s" on an undefined value
632
633(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
634object reference or package name contains an undefined value. Something
635like this will reproduce the error:
6df41af2
GS
636
637 $BADREF = undef;
638 process $BADREF 1,2,3;
639 $BADREF->process(1,2,3);
640
a0d0e21e
LW
641=item Can't call method "%s" on unblessed reference
642
54310121 643(F) A method call must know in what package it's supposed to run. It
be771a83
GS
644ordinarily finds this out from the object reference you supply, but you
645didn't supply an object reference in this case. A reference isn't an
646object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
647
648=item Can't call method "%s" without a package or object reference
649
650(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
651object reference or package name contains an expression that returns a
652defined value which is neither an object reference nor a package name.
72b5445b
GS
653Something like this will reproduce the error:
654
655 $BADREF = 42;
656 process $BADREF 1,2,3;
657 $BADREF->process(1,2,3);
658
dfe378f1
FC
659=item Can't call mro_isa_changed_in() on anonymous symbol table
660
661(P) Perl got confused as to whether a hash was a plain hash or a
662symbol table hash when trying to update @ISA caches.
663
2bf7e7b2
FC
664=item Can't call mro_method_changed_in() on anonymous symbol table
665
666(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
667not attached to the symbol table.
668
a0d0e21e
LW
669=item Can't chdir to %s
670
f703fc96 671(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
672that you can chdir to, possibly because it doesn't exist.
673
0545a864 674=item Can't check filesystem of script "%s" for nosuid
104d25b7 675
be771a83
GS
676(P) For some reason you can't check the filesystem of the script for
677nosuid.
104d25b7 678
22e74366 679=item Can't coerce %s to %s in %s
a0d0e21e
LW
680
681(F) Certain types of SVs, in particular real symbol table entries
55497cff 682(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
683say things like:
684
685 *foo += 1;
686
687You CAN say
688
689 $foo = *foo;
690 $foo += 1;
691
692but then $foo no longer contains a glob.
693
0d863452 694=item Can't "continue" outside a when block
dc57907a 695
0d863452
RH
696(F) You called C<continue>, but you're not inside a C<when>
697or C<default> block.
698
a0d0e21e
LW
699=item Can't create pipe mailbox
700
be771a83
GS
701(P) An error peculiar to VMS. The process is suffering from exhausted
702quotas or other plumbing problems.
a0d0e21e 703
eb64745e
GS
704=item Can't declare %s in "%s"
705
30c282f6
NC
706(F) Only scalar, array, and hash variables may be declared as "my", "our" or
707"state" variables. They must have ordinary identifiers as names.
a0d0e21e 708
fc7debfb
FC
709=item Can't "default" outside a topicalizer
710
711(F) You have used a C<default> block that is neither inside a
712C<foreach> loop nor a C<given> block. (Note that this error is
713issued on exit from the C<default> block, so you won't get the
714error if you use an explicit C<continue>.)
715
6df41af2
GS
716=item Can't do inplace edit: %s is not a regular file
717
be771a83 718(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 719a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 720
a0d0e21e
LW
721=item Can't do inplace edit on %s: %s
722
be771a83
GS
723(S inplace) The creation of the new file failed for the indicated
724reason.
a0d0e21e 725
54310121 726=item Can't do inplace edit without backup
a0d0e21e 727
be771a83
GS
728(F) You're on a system such as MS-DOS that gets confused if you try
729reading from a deleted (but still opened) file. You have to say
730C<-i.bak>, or some such.
a0d0e21e 731
10f9c03d 732=item Can't do inplace edit: %s would not be unique
a0d0e21e 733
e476b1b5 734(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
735characters and Perl was unable to create a unique filename during
736inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 737
a0d0e21e
LW
738=item Can't do waitpid with flags
739
be771a83
GS
740(F) This machine doesn't have either waitpid() or wait4(), so only
741waitpid() without flags is emulated.
a0d0e21e 742
a0d0e21e
LW
743=item Can't emulate -%s on #! line
744
be771a83
GS
745(F) The #! line specifies a switch that doesn't make sense at this
746point. For example, it'd be kind of silly to put a B<-x> on the #!
747line.
a0d0e21e 748
1109a392
MHM
749=item Can't %s %s-endian %ss on this platform
750
751(F) Your platform's byte-order is neither big-endian nor little-endian,
752or it has a very strange pointer size. Packing and unpacking big- or
753little-endian floating point values and pointers may not be possible.
754See L<perlfunc/pack>.
755
a0d0e21e
LW
756=item Can't exec "%s": %s
757
d1be9408 758(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
759named program for the indicated reason. Typical reasons include: the
760permissions were wrong on the file, the file wasn't found in
761C<$ENV{PATH}>, the executable in question was compiled for another
762architecture, or the #! line in a script points to an interpreter that
763can't be run for similar reasons. (Or maybe your system doesn't support
764#! at all.)
a0d0e21e
LW
765
766=item Can't exec %s
767
be771a83
GS
768(F) Perl was trying to execute the indicated program for you because
769that's what the #! line said. If that's not what you wanted, you may
770need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
771
772=item Can't execute %s
773
be771a83
GS
774(F) You used the B<-S> switch, but the copies of the script to execute
775found in the PATH did not have correct permissions.
2a92aaa0 776
6df41af2 777=item Can't find an opnumber for "%s"
2a92aaa0 778
be771a83
GS
779(F) A string of a form C<CORE::word> was given to prototype(), but there
780is no builtin with the name C<word>.
6df41af2 781
56ca2fc0
JH
782=item Can't find %s character property "%s"
783
784(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 785could not be found. Maybe you misspelled the name of the property?
e1b711da 786See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 787for a complete list of available official properties.
56ca2fc0 788
6df41af2
GS
789=item Can't find label %s
790
be771a83
GS
791(F) You said to goto a label that isn't mentioned anywhere that it's
792possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
793
794=item Can't find %s on PATH
795
be771a83
GS
796(F) You used the B<-S> switch, but the script to execute could not be
797found in the PATH.
a0d0e21e 798
6df41af2 799=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 800
be771a83
GS
801(F) You used the B<-S> switch, but the script to execute could not be
802found in the PATH, or at least not with the correct permissions. The
803script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
804
805=item Can't find string terminator %s anywhere before EOF
806
be771a83
GS
807(F) Perl strings can stretch over multiple lines. This message means
808that the closing delimiter was omitted. Because bracketed quotes count
809nesting levels, the following is missing its final parenthesis:
a0d0e21e 810
fb73857a
PP
811 print q(The character '(' starts a side comment.);
812
97b3d10f 813If you're getting this error from a here-document, you may have
b6b8cb97
FC
814included unseen whitespace before or after your closing tag or there
815may not be a linebreak after it. A good programmer's editor will have
816a way to help you find these characters (or lack of characters). See
817L<perlop> for the full details on here-documents.
a0d0e21e 818
660a4616
ST
819=item Can't find Unicode property definition "%s"
820
5f8ad6b6
FC
821(F) You may have tried to use C<\p> which means a Unicode
822property (for example C<\p{Lu}> matches all uppercase
fa816bf3 823letters). If you did mean to use a Unicode property, see
e1b711da 824L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 825for a complete list of available properties. If you didn't
fa816bf3
FC
826mean to use a Unicode property, escape the C<\p>, either by
827C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 828until C<\E>).
660a4616 829
b3647a36 830=item Can't fork: %s
a0d0e21e 831
be771a83
GS
832(F) A fatal error occurred while trying to fork while opening a
833pipeline.
a0d0e21e 834
b3647a36
SR
835=item Can't fork, trying again in 5 seconds
836
c973c02e 837(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
838after five seconds.
839
748a9306
LW
840=item Can't get filespec - stale stat buffer?
841
be771a83
GS
842(S) A warning peculiar to VMS. This arises because of the difference
843between access checks under VMS and under the Unix model Perl assumes.
844Under VMS, access checks are done by filename, rather than by bits in
845the stat buffer, so that ACLs and other protections can be taken into
846account. Unfortunately, Perl assumes that the stat buffer contains all
847the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 848the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
849the device name and FID present in the stat buffer, but this works only
850if you haven't made a subsequent call to the CRTL stat() routine,
851because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
852appears, the name lookup failed, and the access-checking routine gave up
853and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
854routine knows about the Perl C<stat> operator and file tests, so you
855shouldn't ever see this warning in response to a Perl command; it arises
856only if some internal code takes stat buffers lightly.)
748a9306 857
a0d0e21e
LW
858=item Can't get pipe mailbox device name
859
be771a83
GS
860(P) An error peculiar to VMS. After creating a mailbox to act as a
861pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
862
863=item Can't get SYSGEN parameter value for MAXBUF
864
748a9306
LW
865(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
866mailbox buffers to be, and didn't get an answer.
a0d0e21e 867
6df41af2 868=item Can't "goto" into the middle of a foreach loop
a0d0e21e 869
be771a83
GS
870(F) A "goto" statement was executed to jump into the middle of a foreach
871loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
872
873=item Can't "goto" out of a pseudo block
874
be771a83
GS
875(F) A "goto" statement was executed to jump out of what might look like
876a block, except that it isn't a proper block. This usually occurs if
877you tried to jump out of a sort() block or subroutine, which is a no-no.
878See L<perlfunc/goto>.
a0d0e21e 879
5a25739d
FC
880=item Can't goto subroutine from an eval-%s
881
882(F) The "goto subroutine" call can't be used to jump out of an eval
883"string" or block.
884
9850bf21 885=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 886
9850bf21
RH
887(F) The "goto subroutine" call can't be used to jump out of the
888comparison sub for a sort(), or from a similar callback (such
889as the reduce() function in List::Util).
890
6df41af2
GS
891=item Can't goto subroutine outside a subroutine
892
be771a83
GS
893(F) The deeply magical "goto subroutine" call can only replace one
894subroutine call for another. It can't manufacture one out of whole
895cloth. In general you should be calling it out of only an AUTOLOAD
896routine anyway. See L<perlfunc/goto>.
6df41af2 897
0b5b802d
GS
898=item Can't ignore signal CHLD, forcing to default
899
be771a83
GS
900(W signal) Perl has detected that it is being run with the SIGCHLD
901signal (sometimes known as SIGCLD) disabled. Since disabling this
902signal will interfere with proper determination of exit status of child
903processes, Perl has reset the signal to its default value. This
904situation typically indicates that the parent program under which Perl
905may be running (e.g. cron) is being very careless.
0b5b802d 906
e2c0f81f
DG
907=item Can't kill a non-numeric process ID
908
909(F) Process identifiers must be (signed) integers. It is a fatal error to
910attempt to kill() an undefined, empty-string or otherwise non-numeric
911process identifier.
912
6df41af2 913=item Can't "last" outside a loop block
4633a7c4 914
6df41af2 915(F) A "last" statement was executed to break out of the current block,
be771a83
GS
916except that there's this itty bitty problem called there isn't a current
917block. Note that an "if" or "else" block doesn't count as a "loopish"
918block, as doesn't a block given to sort(), map() or grep(). You can
919usually double the curlies to get the same effect though, because the
920inner curlies will be considered a block that loops once. See
921L<perlfunc/last>.
4633a7c4 922
2c7d6b9c
RGS
923=item Can't linearize anonymous symbol table
924
925(F) Perl tried to calculate the method resolution order (MRO) of a
926package, but failed because the package stash has no name.
927
b8170e59
JB
928=item Can't load '%s' for module %s
929
6903afa2
FC
930(F) The module you tried to load failed to load a dynamic extension.
931This may either mean that you upgraded your version of perl to one
932that is incompatible with your old dynamic extensions (which is known
933to happen between major versions of perl), or (more likely) that your
934dynamic extension was built against an older version of the library
935that is installed on your system. You may need to rebuild your old
936dynamic extensions.
b8170e59 937
748a9306
LW
938=item Can't localize lexical variable %s
939
2ba9eb46 940(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
941lexical variable using "my" or "state". This is not allowed. If you
942want to localize a package variable of the same name, qualify it with
943the package name.
748a9306 944
6df41af2 945=item Can't localize through a reference
4727527e 946
6df41af2
GS
947(F) You said something like C<local $$ref>, which Perl can't currently
948handle, because when it goes to restore the old value of whatever $ref
be771a83 949pointed to after the scope of the local() is finished, it can't be sure
64977eb6 950that $ref will still be a reference.
4727527e 951
ea071790 952=item Can't locate %s
ec889f3a 953
fa816bf3
FC
954(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
955Perl looks for the file in all the locations mentioned in @INC, unless
956the file name included the full path to the file. Perhaps you need
957to set the PERL5LIB or PERL5OPT environment variable to say where the
958extra library is, or maybe the script needs to add the library name
be771a83
GS
959to @INC. Or maybe you just misspelled the name of the file. See
960L<perlfunc/require> and L<lib>.
a0d0e21e 961
6df41af2
GS
962=item Can't locate auto/%s.al in @INC
963
be771a83
GS
964(F) A function (or method) was called in a package which allows
965autoload, but there is no function to autoload. Most probable causes
966are a misprint in a function/method name or a failure to C<AutoSplit>
967the file, say, by doing C<make install>.
6df41af2 968
b8170e59
JB
969=item Can't locate loadable object for module %s in @INC
970
971(F) The module you loaded is trying to load an external library, like
d70d8e57 972for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
973unable to locate this library. See L<DynaLoader>.
974
a0d0e21e
LW
975=item Can't locate object method "%s" via package "%s"
976
977(F) You called a method correctly, and it correctly indicated a package
978functioning as a class, but that package doesn't define that particular
2ba9eb46 979method, nor does any of its base classes. See L<perlobj>.
a0d0e21e
LW
980
981=item Can't locate package %s for @%s::ISA
982
be771a83
GS
983(W syntax) The @ISA array contained the name of another package that
984doesn't seem to exist.
a0d0e21e 985
2f7da168
RK
986=item Can't locate PerlIO%s
987
988(F) You tried to use in open() a PerlIO layer that does not exist,
989e.g. open(FH, ">:nosuchlayer", "somefile").
990
f4ad53f4 991=item Can't make list assignment to %ENV on this system
3e3baf6d 992
be771a83
GS
993(F) List assignment to %ENV is not supported on some systems, notably
994VMS.
3e3baf6d 995
cd40cd58
NC
996=item Can't make loaded symbols global on this platform while loading %s
997
ff9c1ae8 998(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
999that symbols from the stated file are made available globally within the
1000process, but that functionality is not available on this platform. Whilst
1001the module likely will still work, this may prevent the perl interpreter
1002from loading other XS-based extensions which need to link directly to
1003functions defined in the C or XS code in the stated file.
1004
a0d0e21e
LW
1005=item Can't modify %s in %s
1006
be771a83
GS
1007(F) You aren't allowed to assign to the item indicated, or otherwise try
1008to change it, such as with an auto-increment.
a0d0e21e 1009
54310121 1010=item Can't modify nonexistent substring
a0d0e21e
LW
1011
1012(P) The internal routine that does assignment to a substr() was handed
1013a NULL.
1014
6df41af2
GS
1015=item Can't modify non-lvalue subroutine call
1016
1017(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1018such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1019
5f05dabc 1020=item Can't msgrcv to read-only var
a0d0e21e 1021
5f05dabc 1022(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1023buffer.
1024
6df41af2
GS
1025=item Can't "next" outside a loop block
1026
1027(F) A "next" statement was executed to reiterate the current block, but
1028there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1029count as a "loopish" block, as doesn't a block given to sort(), map() or
1030grep(). You can usually double the curlies to get the same effect
1031though, because the inner curlies will be considered a block that loops
1032once. See L<perlfunc/next>.
6df41af2 1033
a0d0e21e
LW
1034=item Can't open %s: %s
1035
c47ff5f1 1036(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1037filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1038switches, or explicitly, failed for the indicated reason. Usually
1039this is because you don't have read permission for a file which
1040you named on the command line.
1041
1042(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1043your operating system's equivalent) could not be opened.
a0d0e21e 1044
9a869a14
RGS
1045=item Can't open a reference
1046
1047(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1048using the 3-arg open() syntax:
9a869a14
RGS
1049
1050 open FH, '>', $ref;
1051
1052but your version of perl is compiled without perlio, and this form of
1053open is not supported.
1054
a0d0e21e
LW
1055=item Can't open bidirectional pipe
1056
be771a83
GS
1057(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1058You can try any of several modules in the Perl library to do this, such
1059as IPC::Open2. Alternately, direct the pipe's output to a file using
1060">", and then read it in under a different file handle.
a0d0e21e 1061
748a9306
LW
1062=item Can't open error file %s as stderr
1063
be771a83
GS
1064(F) An error peculiar to VMS. Perl does its own command line
1065redirection, and couldn't open the file specified after '2>' or '2>>' on
1066the command line for writing.
748a9306
LW
1067
1068=item Can't open input file %s as stdin
1069
be771a83
GS
1070(F) An error peculiar to VMS. Perl does its own command line
1071redirection, and couldn't open the file specified after '<' on the
1072command line for reading.
748a9306
LW
1073
1074=item Can't open output file %s as stdout
1075
be771a83
GS
1076(F) An error peculiar to VMS. Perl does its own command line
1077redirection, and couldn't open the file specified after '>' or '>>' on
1078the command line for writing.
748a9306
LW
1079
1080=item Can't open output pipe (name: %s)
1081
be771a83
GS
1082(P) An error peculiar to VMS. Perl does its own command line
1083redirection, and couldn't open the pipe into which to send data destined
1084for stdout.
748a9306 1085
3b1cf97d 1086=item Can't open perl script "%s": %s
a0d0e21e
LW
1087
1088(F) The script you specified can't be opened for the indicated reason.
1089
fa3aa65a
JC
1090If you're debugging a script that uses #!, and normally relies on the
1091shell's $PATH search, the -S option causes perl to do that search, so
1092you don't have to type the path or C<`which $scriptname`>.
1093
6df41af2
GS
1094=item Can't read CRTL environ
1095
1096(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1097from the CRTL's internal environment array and discovered the array was
1098missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1099or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1100searched.
6df41af2 1101
6df41af2
GS
1102=item Can't "redo" outside a loop block
1103
1104(F) A "redo" statement was executed to restart the current block, but
1105there isn't a current block. Note that an "if" or "else" block doesn't
1106count as a "loopish" block, as doesn't a block given to sort(), map()
1107or grep(). You can usually double the curlies to get the same effect
1108though, because the inner curlies will be considered a block that
1109loops once. See L<perlfunc/redo>.
1110
64977eb6 1111=item Can't remove %s: %s, skipping file
10f9c03d 1112
be771a83
GS
1113(S inplace) You requested an inplace edit without creating a backup
1114file. Perl was unable to remove the original file to replace it with
1115the modified file. The file was left unmodified.
10f9c03d 1116
a0d0e21e
LW
1117=item Can't rename %s to %s: %s, skipping file
1118
e476b1b5 1119(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1120probably because you don't have write permission to the directory.
a0d0e21e 1121
748a9306
LW
1122=item Can't reopen input pipe (name: %s) in binary mode
1123
be771a83
GS
1124(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1125to reopen it to accept binary data. Alas, it failed.
748a9306 1126
4f12ec0e
FC
1127=item Can't reset %ENV on this system
1128
1129(F) You called C<reset('E')> or similar, which tried to reset
1130all variables in the current package beginning with "E". In
1131the main package, that includes %ENV. Resetting %ENV is not
1132supported on some systems, notably VMS.
1133
fe13d51d 1134=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1135
1fa582fa
FC
1136(F)(P) Error resolving overloading specified by a method name (as
1137opposed to a subroutine reference): no such method callable via the
1138package. If the method name is C<???>, this is an internal error.
6df41af2 1139
cd06dffe
GS
1140=item Can't return %s from lvalue subroutine
1141
be771a83
GS
1142(F) Perl detected an attempt to return illegal lvalues (such as
1143temporary or readonly values) from a subroutine used as an lvalue. This
1144is not allowed.
cd06dffe 1145
96ebfdd7
RK
1146=item Can't return outside a subroutine
1147
1148(F) The return statement was executed in mainline code, that is, where
1149there was no subroutine call to return out of. See L<perlsub>.
1150
78f9721b
SM
1151=item Can't return %s to lvalue scalar context
1152
6903afa2
FC
1153(F) You tried to return a complete array or hash from an lvalue
1154subroutine, but you called the subroutine in a way that made Perl
1155think you meant to return only one value. You probably meant to
1156write parentheses around the call to the subroutine, which tell
1157Perl that the call should be in list context.
78f9721b 1158
a0d0e21e
LW
1159=item Can't stat script "%s"
1160
be771a83
GS
1161(P) For some reason you can't fstat() the script even though you have it
1162open already. Bizarre.
a0d0e21e 1163
a0d0e21e
LW
1164=item Can't take log of %g
1165
fb73857a 1166(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1167negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1168standard with Perl, though, if you really want to do that for the
1169negative numbers.
a0d0e21e
LW
1170
1171=item Can't take sqrt of %g
1172
1173(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1174negative number. There's a Math::Complex package that comes standard
1175with Perl, though, if you really want to do that.
a0d0e21e
LW
1176
1177=item Can't undef active subroutine
1178
1179(F) You can't undefine a routine that's currently running. You can,
1180however, redefine it while it's running, and you can even undef the
1181redefined subroutine while the old routine is running. Go figure.
1182
c81225bc 1183=item Can't upgrade %s (%d) to %d
a0d0e21e 1184
be771a83
GS
1185(P) The internal sv_upgrade routine adds "members" to an SV, making it
1186into a more specialized kind of SV. The top several SV types are so
1187specialized, however, that they cannot be interconverted. This message
1188indicates that such a conversion was attempted.
a0d0e21e 1189
6651ba0b
FC
1190=item Can't use '%c' after -mname
1191
1192(F) You tried to call perl with the B<-m> switch, but you put something
1193other than "=" after the module name.
1194
1f1ec7b5
KW
1195=item Can't use a hash as a reference
1196
1197(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1198C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1199<= 5.22.0 used to allow this syntax, but shouldn't
1200have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1201
1202=item Can't use an array as a reference
1203
1204(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1205C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1206used to allow this syntax, but shouldn't have. This
1207was deprecated in perl 5.6.1.
1f1ec7b5 1208
1db89ea5
BS
1209=item Can't use anonymous symbol table for method lookup
1210
e27ad1f2 1211(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1212table that doesn't have a name. Symbol tables can become anonymous
1213for example by undefining stashes: C<undef %Some::Package::>.
1214
96ebfdd7
RK
1215=item Can't use an undefined value as %s reference
1216
1217(F) A value used as either a hard reference or a symbolic reference must
1218be a defined value. This helps to delurk some insidious errors.
1219
6df41af2
GS
1220=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1221
be771a83
GS
1222(F) Only hard references are allowed by "strict refs". Symbolic
1223references are disallowed. See L<perlref>.
6df41af2 1224
90b75b61 1225=item Can't use %! because Errno.pm is not available
1d2dff63 1226
20561843 1227(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1228Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1229provide symbolic names for C<$!> errno values.
1230
1109a392
MHM
1231=item Can't use both '<' and '>' after type '%c' in %s
1232
1233(F) A type cannot be forced to have both big-endian and little-endian
1234byte-order at the same time, so this combination of modifiers is not
1235allowed. See L<perlfunc/pack>.
1236
e35475de
KW
1237=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1238
1239(F) defined() is not useful on arrays because it
1240checks for an undefined I<scalar> value. If you want to see if the
1241array is empty, just use C<if (@array) { # not empty }> for example.
1242
1243=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1244
1245(F) C<defined()> is not usually right on hashes.
1246
1247Although C<defined %hash> is false on a plain not-yet-used hash, it
1248becomes true in several non-obvious circumstances, including iterators,
1249weak references, stash names, even remaining true after C<undef %hash>.
1250These things make C<defined %hash> fairly useless in practice, so it now
1251generates a fatal error.
1252
1253If a check for non-empty is what you wanted then just put it in boolean
1254context (see L<perldata/Scalar values>):
1255
1256 if (%hash) {
1257 # not empty
1258 }
1259
1260If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1261variable exists then that's never really been reliable, and isn't
1262a good way to enquire about the features of a package, or whether
1263it's loaded, etc.
1264
6df41af2
GS
1265=item Can't use %s for loop variable
1266
be771a83
GS
1267(F) Only a simple scalar variable may be used as a loop variable on a
1268foreach.
6df41af2 1269
aab6a793 1270=item Can't use global %s in "%s"
6df41af2 1271
be771a83
GS
1272(F) You tried to declare a magical variable as a lexical variable. This
1273is not allowed, because the magic can be tied to only one location
1274(namely the global variable) and it would be incredibly confusing to
1275have variables in your program that looked like magical variables but
6df41af2
GS
1276weren't.
1277
6d3b25aa
RGS
1278=item Can't use '%c' in a group with different byte-order in %s
1279
1280(F) You attempted to force a different byte-order on a type
1281that is already inside a group with a byte-order modifier.
1282For example you cannot force little-endianness on a type that
1283is inside a big-endian group.
1284
c07a80fd
PP
1285=item Can't use "my %s" in sort comparison
1286
1287(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1288You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1289and the variable had earlier been declared as a lexical variable.
1290Either qualify the sort variable with the package name, or rename the
1291lexical variable.
1292
a0d0e21e
LW
1293=item Can't use %s ref as %s ref
1294
1295(F) You've mixed up your reference types. You have to dereference a
1296reference of the type needed. You can use the ref() function to
1297test the type of the reference, if need be.
1298
748a9306 1299=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1300
5e634d20
FC
1301=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1302
b41bf23f
FC
1303(F) You've told Perl to dereference a string, something which
1304C<use strict> blocks to prevent it happening accidentally. See
1305L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1306in a double-quoted string immediately before interpolating a variable,
1307for example in C<"user @$twitter_id">, which says to treat the contents
1308of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1309symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1310
748a9306
LW
1311=item Can't use subscript on %s
1312
1313(F) The compiler tried to interpret a bracketed expression as a
1314subscript. But to the left of the brackets was an expression that
209e7cf1 1315didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1316
6df41af2
GS
1317=item Can't use \%c to mean $%c in expression
1318
75b44862
GS
1319(W syntax) In an ordinary expression, backslash is a unary operator that
1320creates a reference to its argument. The use of backslash to indicate a
1321backreference to a matched substring is valid only as part of a regular
be771a83
GS
1322expression pattern. Trying to do this in ordinary Perl code produces a
1323value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1324instead.
6df41af2 1325
810b8aa5
GS
1326=item Can't weaken a nonreference
1327
1328(F) You attempted to weaken something that was not a reference. Only
1329references can be weakened.
1330
fc7debfb
FC
1331=item Can't "when" outside a topicalizer
1332
1333(F) You have used a when() block that is neither inside a C<foreach>
1334loop nor a C<given> block. (Note that this error is issued on exit
1335from the C<when> block, so you won't get the error if the match fails,
1336or if you use an explicit C<continue>.)
1337
5f05dabc 1338=item Can't x= to read-only value
a0d0e21e 1339
be771a83
GS
1340(F) You tried to repeat a constant value (often the undefined value)
1341with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1342Perhaps you need to copy the value to a temporary, and repeat that.
1343
a04e6aad 1344=item Character following "\c" must be printable ASCII
f9d13529 1345
7357bd17 1346(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1347
727b6379 1348Note that ASCII characters that don't map to control characters are
7357bd17 1349discouraged, and will generate the warning (when enabled)
727b6379 1350L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1351
f337b084 1352=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1353
1354(W pack) You said
1355
1356 pack("C", $x)
1357
1358where $x is either less than 0 or more than 255; the C<"C"> format is
1359only for encoding native operating system characters (ASCII, EBCDIC,
1360and so on) and not for Unicode characters, so Perl behaved as if you meant
1361
1362 pack("C", $x & 255)
1363
1364If you actually want to pack Unicode codepoints, use the C<"U"> format
1365instead.
1366
f337b084 1367=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1368
1369(W pack) You said
1370
1371 pack("c", $x)
1372
1373where $x is either less than -128 or more than 127; the C<"c"> format
1374is only for encoding native operating system characters (ASCII, EBCDIC,
1375and so on) and not for Unicode characters, so Perl behaved as if you meant
1376
1377 pack("c", $x & 255);
1378
1379If you actually want to pack Unicode codepoints, use the C<"U"> format
1380instead.
1381
f337b084
TH
1382=item Character in '%c' format wrapped in unpack
1383
1384(W unpack) You tried something like
1385
1386 unpack("H", "\x{2a1}")
1387
1a147d38 1388where the format expects to process a byte (a character with a value
6903afa2
FC
1389below 256), but a higher value was provided instead. Perl uses the
1390value modulus 256 instead, as if you had provided:
f337b084
TH
1391
1392 unpack("H", "\x{a1}")
1393
5a25739d
FC
1394=item Character in 'W' format wrapped in pack
1395
1396(W pack) You said
1397
1398 pack("U0W", $x)
1399
1400where $x is either less than 0 or more than 255. However, C<U0>-mode
1401expects all values to fall in the interval [0, 255], so Perl behaved
1402as if you meant:
1403
1404 pack("U0W", $x & 255)
1405
f337b084
TH
1406=item Character(s) in '%c' format wrapped in pack
1407
1408(W pack) You tried something like
1409
1410 pack("u", "\x{1f3}b")
1411
1a147d38 1412where the format expects to process a sequence of bytes (character with a
6903afa2 1413value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1414uses the character values modulus 256 instead, as if you had provided:
1415
1416 pack("u", "\x{f3}b")
1417
1418=item Character(s) in '%c' format wrapped in unpack
1419
1420(W unpack) You tried something like
1421
1422 unpack("s", "\x{1f3}b")
1423
1a147d38 1424where the format expects to process a sequence of bytes (character with a
6903afa2 1425value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1426uses the character values modulus 256 instead, as if you had provided:
1427
1428 unpack("s", "\x{f3}b")
1429
f866a7cd
FC
1430=item "\c%c" is more clearly written simply as "%s"
1431
1432(W syntax) The C<\cI<X>> construct is intended to be a way to specify
1433non-printable characters. You used it for a printable one, which is better
1434written as simply itself, perhaps preceded by a backslash for non-word
1435characters.
1436
6651ba0b
FC
1437=item Cloning substitution context is unimplemented
1438
1439(F) Creating a new thread inside the C<s///> operator is not supported.
1440
abc7ecad
SP
1441=item closedir() attempted on invalid dirhandle %s
1442
1443(W io) The dirhandle you tried to close is either closed or not really
1444a dirhandle. Check your control flow.
1445
5a25739d
FC
1446=item close() on unopened filehandle %s
1447
1448(W unopened) You tried to close a filehandle that was never opened.
1449
541ed3a9
FC
1450=item Closure prototype called
1451
1452(F) If a closure has attributes, the subroutine passed to an attribute
1453handler is the prototype that is cloned when a new closure is created.
1454This subroutine cannot be called.
1455
49704364
LW
1456=item Code missing after '/'
1457
6903afa2
FC
1458(F) You had a (sub-)template that ends with a '/'. There must be
1459another template code following the slash. See L<perlfunc/pack>.
49704364 1460
5a25739d
FC
1461=item Code point 0x%X is not Unicode, may not be portable
1462
2d88a86a 1463(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1464of U+10FFFF.
1465
1466Perl allows strings to contain a superset of Unicode code points, up
1467to the limit of what is storable in an unsigned integer on your system,
1468but these may not be accepted by other languages/systems. At one time,
1469it was legal in some standards to have code points up to 0x7FFF_FFFF,
1470but not higher. Code points above 0xFFFF_FFFF require larger than a
147132 bit word.
0876b9a0 1472
6df41af2
GS
1473=item %s: Command not found
1474
a892b81a 1475(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1476instead of Perl. Check the #! line, or manually feed your script into
1477Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1478
1479 #!/usr/bin/perl -w
6df41af2 1480
7a2e2cd6
PP
1481=item Compilation failed in require
1482
1483(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1484Perl uses this generic message when none of the errors that it
1485encountered were severe enough to halt compilation immediately.
7a2e2cd6 1486
c3464db5
DD
1487=item Complex regular subexpression recursion limit (%d) exceeded
1488
be771a83
GS
1489(W regexp) The regular expression engine uses recursion in complex
1490situations where back-tracking is required. Recursion depth is limited
1491to 32766, or perhaps less in architectures where the stack cannot grow
1492arbitrarily. ("Simple" and "medium" situations are handled without
1493recursion and are not subject to a limit.) Try shortening the string
1494under examination; looping in Perl code (e.g. with C<while>) rather than
1495in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1496that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1497on I<Mastering Regular Expressions>.)
c3464db5 1498
69282e91 1499=item connect() on closed socket %s
a0d0e21e 1500
be771a83
GS
1501(W closed) You tried to do a connect on a closed socket. Did you forget
1502to check the return value of your socket() call? See
1503L<perlfunc/connect>.
a0d0e21e 1504
e21e7c6a
FC
1505=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1506
1507(F) The subroutine registered to handle constant overloading
1508(see L<overload>) or a custom charnames handler (see
1509L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1510
1511=item Constant(%s): $^H{%s} is not defined
1512
1513(F) The parser found inconsistencies while attempting to define an
1514overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1515L<overload> pragma?
e21e7c6a 1516
779c5bc9
GS
1517=item Constant is not %s reference
1518
1519(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1520is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1521The message indicates the type of reference that was expected. This
be771a83 1522usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1523See L<perlsub/"Constant Functions"> and L<constant>.
1524
4cee8e80
CS
1525=item Constant subroutine %s redefined
1526
aeb94125
FC
1527(W redefine)(S) You redefined a subroutine which had previously
1528been eligible for inlining. See L<perlsub/"Constant Functions">
1529for commentary and workarounds.
4cee8e80 1530
9607fc9c
PP
1531=item Constant subroutine %s undefined
1532
be771a83
GS
1533(W misc) You undefined a subroutine which had previously been eligible
1534for inlining. See L<perlsub/"Constant Functions"> for commentary and
1535workarounds.
9607fc9c 1536
5a25739d
FC
1537=item Constant(%s) unknown
1538
1539(F) The parser found inconsistencies either while attempting
1540to define an overloaded constant, or when trying to find the
1541character name specified in the C<\N{...}> escape. Perhaps you
1542forgot to load the corresponding L<overload> pragma?.
1543
e7ea3e70
IZ
1544=item Copy method did not return a reference
1545
6903afa2 1546(F) The method which overloads "=" is buggy. See
13a2d996 1547L<overload/Copy Constructor>.
e7ea3e70 1548
4aaa4757
FC
1549=item &CORE::%s cannot be called directly
1550
1551(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1552with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1553in this package cannot yet be called that way, but must be
1554called as barewords. Something like this will work:
1555
1556 BEGIN { *shove = \&CORE::push; }
1557 shove @array, 1,2,3; # pushes on to @array
1558
6798c92b
GS
1559=item CORE::%s is not a keyword
1560
1561(F) The CORE:: namespace is reserved for Perl keywords.
1562
675fa9ff
FC
1563=item Corrupted regexp opcode %d > %d
1564
1565(P) This is either an error in Perl, or, if you're using
1566one, your L<custom regular expression engine|perlreapi>. If not the
1567latter, report the problem through the L<perlbug> utility.
1568
a0d0e21e
LW
1569=item corrupted regexp pointers
1570
1571(P) The regular expression engine got confused by what the regular
1572expression compiler gave it.
1573
1574=item corrupted regexp program
1575
be771a83
GS
1576(P) The regular expression engine got passed a regexp program without a
1577valid magic number.
a0d0e21e 1578
de42a5a9 1579=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1580
1581(P) The malloc package that comes with Perl had an internal failure.
1582
49704364
LW
1583=item Count after length/code in unpack
1584
1585(F) You had an unpack template indicating a counted-length string, but
1586you have also specified an explicit size for the string. See
1587L<perlfunc/pack>.
1588
f2cccb4c
KW
1589=for comment
1590The following are used in lib/diagnostics.t for testing two =items that
1591share the same description. Changes here need to be propagated to there
1592
6651ba0b
FC
1593=item Deep recursion on anonymous subroutine
1594
a0d0e21e
LW
1595=item Deep recursion on subroutine "%s"
1596
be771a83
GS
1597(W recursion) This subroutine has called itself (directly or indirectly)
1598100 times more than it has returned. This probably indicates an
1599infinite recursion, unless you're writing strange benchmark programs, in
1600which case it indicates something else.
a0d0e21e 1601
aad1d01f
NC
1602This threshold can be changed from 100, by recompiling the F<perl> binary,
1603setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1604
e0e4a6e3
FC
1605=item (?(DEFINE)....) does not allow branches in regex; marked by
1606S<<-- HERE> in m/%s/
bcb95744 1607
6903afa2 1608(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1609most likely cause of this error is that you left out a parenthesis inside
1610of the C<....> part.
1611
9e3ec65c 1612The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1613discovered.
1614
62658f4d
PM
1615=item %s defines neither package nor VERSION--version check failed
1616
1617(F) You said something like "use Module 42" but in the Module file
1618there are neither package declarations nor a C<$VERSION>.
1619
36447869
FC
1620=item delete argument is index/value array slice, use array slice
1621
1622(F) You used index/value array slice syntax (C<%array[...]>) as
1623the argument to C<delete>. You probably meant C<@array[...]> with
1624an @ symbol instead.
1625
1626=item delete argument is key/value hash slice, use hash slice
1627
1628(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1629C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1630
0ffcbc25
FC
1631=item delete argument is not a HASH or ARRAY element or slice
1632
4a0af295 1633(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1634such as:
1635
1636 $foo{$bar}
1637 $ref->{"susie"}[12]
1638
1639or a hash or array slice, such as:
1640
1641 @foo[$bar, $baz, $xyzzy]
1642 @{$ref->[12]}{"susie", "queue"}
1643
fc36a67e
PP
1644=item Delimiter for here document is too long
1645
be771a83
GS
1646(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1647long for Perl to handle. You have to be seriously twisted to write code
1648that triggers this error.
fc36a67e 1649
6d3b25aa
RGS
1650=item Deprecated use of my() in false conditional
1651
fa816bf3
FC
1652(D deprecated) You used a declaration similar to C<my $x if 0>. There
1653has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1654not to be cleared at scope exit when its declaration includes a false
6903afa2 1655conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1656static variable. Since we intend to fix this bug, we don't want people
6903afa2 1657relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1658declaring the variable in a separate block outside the function, eg
36fb85f3 1659
6d3b25aa
RGS
1660 sub f { my $x if 0; return $x++ }
1661
1662becomes
1663
1664 { my $x; sub f { return $x++ } }
1665
ea9d9ebc 1666Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1667lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1668
1669 sub f { state $x; return $x++ }
1670
500ab966
RGS
1671=item DESTROY created new reference to dead object '%s'
1672
1673(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1674just being DESTROYed. Perl is confused, and prefers to abort rather
1675than to create a dangling reference.
500ab966 1676
3cdd684c
TP
1677=item Did not produce a valid header
1678
1679See Server error.
1680
6df41af2
GS
1681=item %s did not return a true value
1682
1683(F) A required (or used) file must return a true value to indicate that
1684it compiled correctly and ran its initialization code correctly. It's
1685traditional to end such a file with a "1;", though any true value would
1686do. See L<perlfunc/require>.
1687
cc507455 1688=item (Did you mean &%s instead?)
4633a7c4 1689
413ff9f6
FC
1690(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1691some such.
4633a7c4 1692
cc507455 1693=item (Did you mean "local" instead of "our"?)
33633739 1694
be771a83
GS
1695(W misc) Remember that "our" does not localize the declared global
1696variable. You have declared it again in the same lexical scope, which
1697seems superfluous.
33633739 1698
cc507455 1699=item (Did you mean $ or @ instead of %?)
a0d0e21e 1700
be771a83
GS
1701(W) You probably said %hash{$key} when you meant $hash{$key} or
1702@hash{@keys}. On the other hand, maybe you just meant %hash and got
1703carried away.
748a9306 1704
7e1af8bc 1705=item Died
5f05dabc
PP
1706
1707(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1708you called it with no args and C<$@> was empty.
5f05dabc 1709
3cdd684c
TP
1710=item Document contains no data
1711
1712See Server error.
1713
62658f4d
PM
1714=item %s does not define %s::VERSION--version check failed
1715
1716(F) You said something like "use Module 42" but the Module did not
943fc58e 1717define a C<$VERSION>.
62658f4d 1718
49704364
LW
1719=item '/' does not take a repeat count
1720
1721(F) You cannot put a repeat count of any kind right after the '/' code.
1722See L<perlfunc/pack>.
1723
95cb0d72
FC
1724=item Don't know how to get file name
1725
1726(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1727somehow called on another platform. This should not happen.
1728
4021c788 1729=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1730
1731(P) The internal handling of magical variables has been cursed.
1732
1733=item do_study: out of memory
1734
1735(P) This should have been caught by safemalloc() instead.
1736
6df41af2
GS
1737=item (Do you need to predeclare %s?)
1738
56da5a46
RGS
1739(S syntax) This is an educated guess made in conjunction with the message
1740"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1741name is being referenced that hasn't been declared yet. This may be
1742because of ordering problems in your file, or because of a missing
be771a83
GS
1743"sub", "package", "require", or "use" statement. If you're referencing
1744something that isn't defined yet, you don't actually have to define the
1745subroutine or package before the current location. You can use an empty
1746"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1747
ac206dc8
RGS
1748=item dump() better written as CORE::dump()
1749
1750(W misc) You used the obsolescent C<dump()> built-in function, without fully
1751qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1752
84d78eb7
YO
1753=item dump is not supported
1754
1755(F) Your machine doesn't support dump/undump.
1756
a0d0e21e
LW
1757=item Duplicate free() ignored
1758
be771a83
GS
1759(S malloc) An internal routine called free() on something that had
1760already been freed.
a0d0e21e 1761
1109a392
MHM
1762=item Duplicate modifier '%c' after '%c' in %s
1763
35f0cd76
FC
1764(W unpack) You have applied the same modifier more than once after a
1765type in a pack template. See L<perlfunc/pack>.
1109a392 1766
0953b66b
FC
1767=item each on reference is experimental
1768
0773cb3e
FC
1769(S experimental::autoderef) C<each> with a scalar argument is experimental
1770and may change or be removed in a future Perl version. If you want to
1771take the risk of using this feature, simply disable this warning:
0953b66b 1772
d401967c 1773 no warnings "experimental::autoderef";
0953b66b 1774
4633a7c4
LW
1775=item elseif should be elsif
1776
fa816bf3
FC
1777(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1778it's ugly. Your code will be interpreted as an attempt to call a method
1779named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1780unlikely to be what you want.
1781
e0e4a6e3 1782=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1783
af6f566e 1784(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1785described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1786a regular expression without specifying the property name.
ab13f0c7 1787
85ab1d1d 1788=item entering effective %s failed
5ff3f7a4 1789
85ab1d1d 1790(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1791effective uids or gids failed.
1792
c038024b
RGS
1793=item %ENV is aliased to %s
1794
1795(F) You're running under taint mode, and the C<%ENV> variable has been
1796aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1797program's environment. This is potentially insecure.
c038024b 1798
748a9306
LW
1799=item Error converting file specification %s
1800
5f05dabc 1801(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1802specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1803single form when it must operate on them directly. Either you've passed
1804an invalid file specification to Perl, or you've found a case the
1805conversion routines don't handle. Drat.
748a9306 1806
ad19ef22 1807=item Eval-group in insecure regular expression
e4d48cc9 1808
be771a83
GS
1809(F) Perl detected tainted data when trying to compile a regular
1810expression that contains the C<(?{ ... })> zero-width assertion, which
1811is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1812
ad19ef22 1813=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1814
be771a83
GS
1815(F) Perl tried to compile a regular expression containing the
1816C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1817pattern contains interpolated values. Since that is a security risk,
1818it is not allowed. If you insist, you may still do this by using the
1819C<re 'eval'> pragma or by explicitly building the pattern from an
1820interpolated string at run time and using that in an eval(). See
1821L<perlre/(?{ code })>.
e4d48cc9 1822
ad19ef22 1823=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1824
be771a83
GS
1825(F) A regular expression contained the C<(?{ ... })> zero-width
1826assertion, but that construct is only allowed when the C<use re 'eval'>
1827pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1828
e0e4a6e3
FC
1829=item EVAL without pos change exceeded limit in regex; marked by
1830S<<-- HERE> in m/%s/
1a147d38
YO
1831
1832(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1833any text. Restructure the pattern so that text is consumed.
1a147d38 1834
9e3ec65c 1835The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1836discovered.
1837
fc36a67e
PP
1838=item Excessively long <> operator
1839
1840(F) The contents of a <> operator may not exceed the maximum size of a
1841Perl identifier. If you're just trying to glob a long list of
1842filenames, try using the glob() operator, or put the filenames into a
1843variable and glob that.
1844
ed9aa3b7
SG
1845=item exec? I'm not *that* kind of operating system
1846
af8bb25a 1847(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1848OS. See L<perlport>.
ed9aa3b7 1849
fe13d51d 1850=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1851
1852(F) The final summary message when a Perl compilation fails.
1853
0ffcbc25
FC
1854=item exists argument is not a HASH or ARRAY element or a subroutine
1855
4a0af295 1856(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1857subroutine with an ampersand, such as:
1858
1859 $foo{$bar}
1860 $ref->{"susie"}[12]
1861 &do_something
1862
1863=item exists argument is not a subroutine name
1864
ccfc2567
FC
1865(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1866and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1867
a0d0e21e
LW
1868=item Exiting eval via %s
1869
be771a83
GS
1870(W exiting) You are exiting an eval by unconventional means, such as a
1871goto, or a loop control statement.
e476b1b5
GS
1872
1873=item Exiting format via %s
1874
9a2ff54b 1875(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1876goto, or a loop control statement.
a0d0e21e 1877
0a753a76
PP
1878=item Exiting pseudo-block via %s
1879
be771a83
GS
1880(W exiting) You are exiting a rather special block construct (like a
1881sort block or subroutine) by unconventional means, such as a goto, or a
1882loop control statement. See L<perlfunc/sort>.
0a753a76 1883
a0d0e21e
LW
1884=item Exiting subroutine via %s
1885
be771a83
GS
1886(W exiting) You are exiting a subroutine by unconventional means, such
1887as a goto, or a loop control statement.
a0d0e21e
LW
1888
1889=item Exiting substitution via %s
1890
be771a83
GS
1891(W exiting) You are exiting a substitution by unconventional means, such
1892as a return, a goto, or a loop control statement.
a0d0e21e 1893
e0e4a6e3 1894=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1895
675fa9ff 1896(F) You wrote something like
c608e803
KW
1897
1898 (?13
1899
1900to denote a capturing group of the form
1901L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1902but omitted the C<")">.
1903
e0e4a6e3 1904=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1905
8b6fbf55
FC
1906(F) The C<(?[...])> extended character class regular expression construct
1907only allows character classes (including character class escapes like
1908C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1909containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1910This allows a regular expression containing just C<(?[...])> to be
1911interpolated. If you see this error message, then you probably
1912have some other C<(?...)> construct inside your character class. See
1913L<perlrecharclass/Extended Bracketed Character Classes>.
1914
30d9c59b
Z
1915=item Experimental subroutine signatures not enabled
1916
1917(F) To use subroutine signatures, you must first enable them:
1918
caa35032 1919 no warnings "experimental::signatures";
30d9c59b
Z
1920 use feature "signatures";
1921 sub foo ($left, $right) { ... }
1922
6da34ecb
FC
1923=item Experimental "%s" subs not enabled
1924
1925(F) To use lexical subs, you must first enable them:
1926
1927 no warnings 'experimental::lexical_subs';
1928 use feature 'lexical_subs';
1929 my sub foo { ... }
1930
7b8d334a
GS
1931=item Explicit blessing to '' (assuming package main)
1932
be771a83
GS
1933(W misc) You are blessing a reference to a zero length string. This has
1934the effect of blessing the reference into the package main. This is
1935usually not what you want. Consider providing a default target package,
1936e.g. bless($ref, $p || 'MyPackage');
7b8d334a 1937
6df41af2
GS
1938=item %s: Expression syntax
1939
be771a83
GS
1940(A) You've accidentally run your script through B<csh> instead of Perl.
1941Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
1942
1943=item %s failed--call queue aborted
1944
3c10abe3
AG
1945(F) An untrapped exception was raised while executing a UNITCHECK,
1946CHECK, INIT, or END subroutine. Processing of the remainder of the
1947queue of such routines has been prematurely ended.
6df41af2 1948
e0e4a6e3 1949=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 1950
98d31c73 1951(W regexp)(F) A character class range must start and end at a literal
7253e4e3 1952character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
1953in your false range is interpreted as a literal "-". In a C<(?[...])>
1954construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 1955the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 1956the problem was discovered. See L<perlre>.
73b437c8 1957
1b1ee2ef 1958=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 1959
be771a83
GS
1960(P) An error peculiar to VMS. Something untoward happened in a VMS
1961system service or RTL routine; Perl's exit status should provide more
1962details. The filename in "at %s" and the line number in "line %d" tell
1963you which section of the Perl source code is distressed.
a0d0e21e
LW
1964
1965=item fcntl is not implemented
1966
1967(F) Your machine apparently doesn't implement fcntl(). What is this, a
1968PDP-11 or something?
1969
22846ab4
AB
1970=item FETCHSIZE returned a negative value
1971
1972(F) A tied array claimed to have a negative number of elements, which
1973is not possible.
1974
f337b084
TH
1975=item Field too wide in 'u' format in pack
1976
d8b5cc61 1977(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
1978which can't encode values above 63. So there is no point in asking for
1979a line length bigger than that. Perl will behave as if you specified
5c96f6f7 1980C<u63> as the format.
f337b084 1981
af8c498a 1982=item Filehandle %s opened only for input
a0d0e21e 1983
6c8d78fb
HS
1984(W io) You tried to write on a read-only filehandle. If you intended
1985it to be a read-write filehandle, you needed to open it with "+<" or
1986"+>" or "+>>" instead of with "<" or nothing. If you intended only to
1987write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 1988
af8c498a 1989=item Filehandle %s opened only for output
a0d0e21e 1990
6c8d78fb
HS
1991(W io) You tried to read from a filehandle opened only for writing, If
1992you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
1993with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
1994read from the file, use "<". See L<perlfunc/open>. Another possibility
1995is that you attempted to open filedescriptor 0 (also known as STDIN) for
1996output (maybe you closed STDIN earlier?).
97828cef
RGS
1997
1998=item Filehandle %s reopened as %s only for input
1999
2000(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2001as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2002previously.
2003
2004=item Filehandle STDIN reopened as %s only for output
2005
2006(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2007as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2008
2009=item Final $ should be \$ or $name
2010
2011(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2012a literal dollar sign, or was meant to introduce a variable name that
2013happens to be missing. So you have to put either the backslash or the
2014name.
a0d0e21e 2015
56e90b21
GS
2016=item flock() on closed filehandle %s
2017
be771a83 2018(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2019some time before now. Check your control flow. flock() operates on
be771a83
GS
2020filehandles. Are you attempting to call flock() on a dirhandle by the
2021same name?
56e90b21 2022
6df41af2
GS
2023=item Format not terminated
2024
2025(F) A format must be terminated by a line with a solitary dot. Perl got
2026to the end of your file without finding such a line.
2027
a0d0e21e
LW
2028=item Format %s redefined
2029
e476b1b5 2030(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2031
2032 {
271595cc 2033 no warnings 'redefine';
a0d0e21e
LW
2034 eval "format NAME =...";
2035 }
2036
a0d0e21e
LW
2037=item Found = in conditional, should be ==
2038
e476b1b5 2039(W syntax) You said
a0d0e21e
LW
2040
2041 if ($foo = 123)
2042
2043when you meant
2044
2045 if ($foo == 123)
2046
2047(or something like that).
2048
6df41af2
GS
2049=item %s found where operator expected
2050
56da5a46
RGS
2051(S syntax) The Perl lexer knows whether to expect a term or an operator.
2052If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2053operator, it gives you this warning. Usually it indicates that an
2054operator or delimiter was omitted, such as a semicolon.
6df41af2 2055
a0d0e21e
LW
2056=item gdbm store returned %d, errno %d, key "%s"
2057
2058(S) A warning from the GDBM_File extension that a store failed.
2059
2060=item gethostent not implemented
2061
2062(F) Your C library apparently doesn't implement gethostent(), probably
2063because if it did, it'd feel morally obligated to return every hostname
2064on the Internet.
2065
69282e91 2066=item get%sname() on closed socket %s
a0d0e21e 2067
be771a83
GS
2068(W closed) You tried to get a socket or peer socket name on a closed
2069socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2070
748a9306
LW
2071=item getpwnam returned invalid UIC %#o for user "%s"
2072
2073(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2074C<getpwnam> operator returned an invalid UIC.
2075
6df41af2
GS
2076=item getsockopt() on closed socket %s
2077
be771a83
GS
2078(W closed) You tried to get a socket option on a closed socket. Did you
2079forget to check the return value of your socket() call? See
6df41af2
GS
2080L<perlfunc/getsockopt>.
2081
0f539b13
BF
2082=item given is experimental
2083
675fa9ff
FC
2084(S experimental::smartmatch) C<given> depends on smartmatch, which
2085is experimental, so its behavior may change or even be removed
2086in any future release of perl. See the explanation under
2087L<perlsyn/Experimental Details on given and when>.
0f539b13 2088
6df41af2
GS
2089=item Global symbol "%s" requires explicit package name
2090
a4edf47d 2091(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2092that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2093declared beforehand using "our", or explicitly qualified to say
2094which package the global variable is in (using "::").
6df41af2 2095
e476b1b5
GS
2096=item glob failed (%s)
2097
5ead438e 2098(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2099for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2100pattern that caused the external program to fail and exit with a
be771a83 2101nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2102resulted in a coredump, this may also mean that your csh (C shell)
2103is broken. If so, you should change all of the csh-related variables
2104in config.sh: If you have tcsh, make the variables refer to it as
2105if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2106all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2107think csh is missing. In either case, after editing config.sh, run
75b44862 2108C<./Configure -S> and rebuild Perl.
e476b1b5 2109
a0d0e21e
LW
2110=item Glob not terminated
2111
2112(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2113a term, so it's looking for the corresponding right angle bracket, and
2114not finding it. Chances are you left some needed parentheses out
2115earlier in the line, and you really meant a "less than".
a0d0e21e 2116
b35b96b6
JH
2117=item gmtime(%f) failed
2118
2119(W overflow) You called C<gmtime> with a number that it could not handle:
2120too large, too small, or NaN. The returned value is C<undef>.
2121
bcd05b94 2122=item gmtime(%f) too large
8b56d6ff 2123
e9200be3 2124(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2125it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2126date. This warning is also triggered with NaN (the special
fc003d4b
MS
2127not-a-number value).
2128
bcd05b94 2129=item gmtime(%f) too small
fc003d4b 2130
e9200be3 2131(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2132it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2133
6df41af2 2134=item Got an error from DosAllocMem
a0d0e21e 2135
6df41af2
GS
2136(P) An error peculiar to OS/2. Most probably you're using an obsolete
2137version of Perl, and this should not happen anyway.
a0d0e21e
LW
2138
2139=item goto must have label
2140
2141(F) Unlike with "next" or "last", you're not allowed to goto an
2142unspecified destination. See L<perlfunc/goto>.
2143
6651ba0b
FC
2144=item Goto undefined subroutine%s
2145
2146(F) You tried to call a subroutine with C<goto &sub> syntax, but
2147the indicated subroutine hasn't been defined, or if it was, it
2148has since been undefined.
2149
6fbc9859 2150=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2151S<<-- HERE> in m/%s/
1f4f6bf1
YO
2152
2153(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2154they must start with a non-digit word character. A common cause of
2155this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2156
5a25739d
FC
2157=item ()-group starts with a count
2158
2159(F) A ()-group started with a count. A count is supposed to follow
2160something: a template character or a ()-group. See L<perlfunc/pack>.
2161
fe13d51d 2162=item %s had compilation errors.
6df41af2
GS
2163
2164(F) The final summary message when a C<perl -c> fails.
2165
a0d0e21e
LW
2166=item Had to create %s unexpectedly
2167
be771a83
GS
2168(S internal) A routine asked for a symbol from a symbol table that ought
2169to have existed already, but for some reason it didn't, and had to be
2170created on an emergency basis to prevent a core dump.
a0d0e21e 2171
6df41af2
GS
2172=item %s has too many errors
2173
2174(F) The parser has given up trying to parse the program after 10 errors.
2175Further error messages would likely be uninformative.
2176
252aa082
JH
2177=item Hexadecimal number > 0xffffffff non-portable
2178
e476b1b5 2179(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2180(4294967295) and therefore non-portable between systems. See
2181L<perlport> for more on portability concerns.
252aa082 2182
8903cb82
PP
2183=item Identifier too long
2184
2185(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2186about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2187names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2188of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2189
e0e4a6e3
FC
2190=item Ignoring zero length \N{} in character class in regex; marked by
2191S<<-- HERE> in m/%s/
fc8cd66c 2192
b5e3739b
FC
2193(W regexp) Named Unicode character escapes C<(\N{...})> may return a
2194zero-length sequence. When such an escape is used in a character class
2195its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2196been used, and the correct charname handler is in scope.
2197
6df41af2 2198=item Illegal binary digit %s
f675dbe5 2199
6df41af2 2200(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2201
6df41af2 2202=item Illegal binary digit %s ignored
a0d0e21e 2203
be771a83
GS
2204(W digit) You may have tried to use a digit other than 0 or 1 in a
2205binary number. Interpretation of the binary number stopped before the
2206offending digit.
a0d0e21e 2207
6597eb22
FC
2208=item Illegal character after '_' in prototype for %s : %s
2209
e4d150f1
FC
2210(W illegalproto) An illegal character was found in a prototype
2211declaration. The '_' in a prototype must be followed by a ';',
2212indicating the rest of the parameters are optional, or one of '@'
2213or '%', since those two will accept 0 or more final parameters.
6597eb22 2214
78d0fecf 2215=item Illegal character \%o (carriage return)
4fdae800 2216
d5898338 2217(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2218would any other whitespace, which means you should never see this error
2219when Perl was built using standard options. For some reason, your
2220version of Perl appears to have been built without this support. Talk
2221to your Perl administrator.
4fdae800 2222
d37a9538
ST
2223=item Illegal character in prototype for %s : %s
2224
197afce1 2225(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2226Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2227Perhaps you were trying to write a subroutine signature but didn't enable
2228that feature first (C<use feature 'signatures'>), so your signature was
2229instead interpreted as a bad prototype.
d37a9538 2230
904d85c5
RGS
2231=item Illegal declaration of anonymous subroutine
2232
2233(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2234you must always specify a block of code. See L<perlsub>.
904d85c5 2235
8e742a20
MHM
2236=item Illegal declaration of subroutine %s
2237
6903afa2 2238(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2239
a0d0e21e
LW
2240=item Illegal division by zero
2241
be771a83
GS
2242(F) You tried to divide a number by 0. Either something was wrong in
2243your logic, or you need to put a conditional in to guard against
2244meaningless input.
a0d0e21e 2245
6df41af2
GS
2246=item Illegal hexadecimal digit %s ignored
2247
be771a83
GS
2248(W digit) You may have tried to use a character other than 0 - 9 or
2249A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2250number stopped before the illegal character.
6df41af2 2251
a0d0e21e
LW
2252=item Illegal modulus zero
2253
be771a83
GS
2254(F) You tried to divide a number by 0 to get the remainder. Most
2255numbers don't take to this kindly.
a0d0e21e 2256
6df41af2 2257=item Illegal number of bits in vec
399388f4 2258
6df41af2
GS
2259(F) The number of bits in vec() (the third argument) must be a power of
2260two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2261
2262=item Illegal octal digit %s
a0d0e21e 2263
d1be9408 2264(F) You used an 8 or 9 in an octal number.
a0d0e21e 2265
399388f4 2266=item Illegal octal digit %s ignored
748a9306 2267
d1be9408 2268(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2269Interpretation of the octal number stopped before the 8 or 9.
748a9306 2270
e0e4a6e3 2271=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2272
675fa9ff 2273(F) You wrote something like
c608e803
KW
2274
2275 (?+foo)
2276
2277The C<"+"> is valid only when followed by digits, indicating a
2278capturing group. See
2279L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2280
375ed12a
JH
2281=item Illegal suidscript
2282
2283(F) The script run under suidperl was somehow illegal.
2284
fe13d51d 2285=item Illegal switch in PERL5OPT: -%c
6ff81951 2286
6df41af2 2287(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2288following switches: B<-[CDIMUdmtw]>.
6ff81951 2289
6df41af2 2290=item Ill-formed CRTL environ value "%s"
81e118e0 2291
75b44862 2292(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2293internal environ array, and encountered an element without the C<=>
2294delimiter used to separate keys from values. The element is ignored.
09bef843 2295
6df41af2 2296=item Ill-formed message in prime_env_iter: |%s|
54310121 2297
be771a83
GS
2298(W internal) A warning peculiar to VMS. Perl tried to read a logical
2299name or CLI symbol definition when preparing to iterate over %ENV, and
2300didn't see the expected delimiter between key and value, so the line was
2301ignored.
54310121 2302
6df41af2 2303=item (in cleanup) %s
9607fc9c 2304
be771a83
GS
2305(W misc) This prefix usually indicates that a DESTROY() method raised
2306the indicated exception. Since destructors are usually called by the
2307system at arbitrary points during execution, and often a vast number of
2308times, the warning is issued only once for any number of failures that
2309would otherwise result in the same message being repeated.
6df41af2 2310
be771a83
GS
2311Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2312also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2313
e0e4a6e3
FC
2314=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2315in m/%s/
0d0b4b3b 2316
675fa9ff 2317(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2318expression inside the construct was completely empty, or if there are
2319too many or few operands for the number of operators. Perl is not smart
2320enough to give you a more precise indication as to what is wrong.
2321
6fbc9859
MH
2322=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2323parent '%s'
2c7d6b9c
RGS
2324
2325(F) The method resolution order (MRO) of the given class is not
2326C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2327documentation in L<mro> for more information.
2328
979699d9
JH
2329=item In EBCDIC the v-string components cannot exceed 2147483647
2330
2331(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2332Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2333encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2334
6a2ed79a 2335=item Infinite recursion in regex
1a147d38
YO
2336
2337(F) You used a pattern that references itself without consuming any input
6903afa2 2338text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2339either consume text or fail.
2340
6dbe9451
NC
2341=item Initialization of state variables in list context currently forbidden
2342
6903afa2
FC
2343(F) Currently the implementation of "state" only permits the
2344initialization of scalar variables in scalar context. Re-write
2345C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2346context. Constructions such as C<state (@a) = foo()> will be
2347supported in a future perl release.
6dbe9451 2348
2186f873
FC
2349=item %%s[%s] in scalar context better written as $%s[%s]
2350
2351(W syntax) In scalar context, you've used an array index/value slice
2352(indicated by %) to select a single element of an array. Generally
2353it's better to ask for a scalar value (indicated by $). The difference
2354is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2355returns and when evaluating its argument, while C<%foo[&bar]> provides
2356a list context to its subscript, which can do weird things if you're
2357expecting only one subscript. When called in list context, it also
2358returns the index (what C<&bar> returns) in addition to the value.
2359
2360=item %%s{%s} in scalar context better written as $%s{%s}
2361
2362(W syntax) In scalar context, you've used a hash key/value slice
2363(indicated by %) to select a single element of a hash. Generally it's
2364better to ask for a scalar value (indicated by $). The difference
2365is that C<$foo{&bar}> always behaves like a scalar, both in the value
2366it returns and when evaluating its argument, while C<@foo{&bar}> and
2367provides a list context to its subscript, which can do weird things
2368if you're expecting only one subscript. When called in list context,
2369it also returns the key in addition to the value.
2370
a0d0e21e
LW
2371=item Insecure dependency in %s
2372
8b1a09fc 2373(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2374The tainting mechanism is turned on when you're running setuid or
2375setgid, or when you specify B<-T> to turn it on explicitly. The
2376tainting mechanism labels all data that's derived directly or indirectly
2377from the user, who is considered to be unworthy of your trust. If any
2378such data is used in a "dangerous" operation, you get this error. See
2379L<perlsec> for more information.
a0d0e21e
LW
2380
2381=item Insecure directory in %s
2382
be771a83
GS
2383(F) You can't use system(), exec(), or a piped open in a setuid or
2384setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2385the world. Also, the PATH must not contain any relative directory.
2386See L<perlsec>.
a0d0e21e 2387
62f468fc 2388=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2389
2390(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2391setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2392C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2393supplied (or potentially supplied) by the user. The script must set
2394the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2395
0e9be77f
DM
2396=item Insecure user-defined property %s
2397
2398(F) Perl detected tainted data when trying to compile a regular
2399expression that contains a call to a user-defined character property
2400function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2401See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2402
cd209d9d 2403=item In '(?...)', the '(' and '?' must be adjacent in regex;
e0e4a6e3 2404marked by S<<-- HERE> in m/%s/
675fa9ff 2405
66a1f5ec
FC
2406(F) The two-character sequence C<"(?"> in this context in a regular
2407expression pattern should be an indivisible token, with nothing
2408intervening between the C<"("> and the C<"?">, but you separated them
2409with whitespace.
675fa9ff 2410
b9ef414d
FC
2411=item Integer overflow in format string for %s
2412
2413(F) The indexes and widths specified in the format string of C<printf()>
2414or C<sprintf()> are too large. The numbers must not overflow the size of
2415integers for your architecture.
2416
a7ae9550
GS
2417=item Integer overflow in %s number
2418
35928bc5 2419(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2420either as a literal or as an argument to hex() or oct() is too big for
2421your architecture, and has been converted to a floating point number.
2422On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2423representable without overflow is 0xFFFFFFFF, 037777777777, or
24240b11111111111111111111111111111111 respectively. Note that Perl
2425transparently promotes all numbers to a floating point representation
2426internally--subject to loss of precision errors in subsequent
2427operations.
bbce6d69 2428
fc89ca81
FC
2429=item Integer overflow in srand
2430
2431(S overflow) The number you have passed to srand is too big to fit
2432in your architecture's integer representation. The number has been
2433replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2434architectures). This means you may be getting less randomness than
2435you expect, because different random seeds above the maximum will
2436return the same sequence of random numbers.
2437
46314c13
JP
2438=item Integer overflow in version
2439
18da5252
FC
2440=item Integer overflow in version %d
2441
784d71ed
FC
2442(W overflow) Some portion of a version initialization is too large for
2443the size of integers for your architecture. This is not a warning
f084e84f 2444because there is no rational reason for a version to try and use an
784d71ed
FC
2445element larger than typically 2**32. This is usually caused by trying
2446to use some odd mathematical operation as a version, like 100/9.
46314c13 2447
e0e4a6e3 2448=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2449
2450(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2451The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2452discovered.
2453
748a9306
LW
2454=item Internal inconsistency in tracking vforks
2455
be771a83
GS
2456(S) A warning peculiar to VMS. Perl keeps track of the number of times
2457you've called C<fork> and C<exec>, to determine whether the current call
2458to C<exec> should affect the current script or a subprocess (see
2459L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2460Perl is making a guess and treating this C<exec> as a request to
2461terminate the Perl script and execute the specified command.
748a9306 2462
870978ae
FC
2463=item internal %<num>p might conflict with future printf extensions
2464
2465(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2466formatting follows a slightly different set of rules when called from
2467C or XS code. Specifically, formats consisting of digits followed
2468by "p" (e.g., "%7p") are reserved for future use. If you see this
2469message, then an XS module tried to call that routine with one such
2470reserved format.
2471
e0e4a6e3 2472=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2473
fa816bf3 2474(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2475S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2476discovered.
a0d0e21e 2477
6df41af2
GS
2478=item %s (...) interpreted as function
2479
75b44862 2480(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2481followed by parentheses turns into a function, with all the list
64977eb6 2482operators arguments found inside the parentheses. See
13a2d996 2483L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2484
09bef843
SB
2485=item Invalid %s attribute: %s
2486
a4a4c9e2 2487(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2488by Perl or by a user-supplied handler. See L<attributes>.
2489
2490=item Invalid %s attributes: %s
2491
a4a4c9e2 2492(F) The indicated attributes for a subroutine or variable were not
be771a83 2493recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2494
e0e4a6e3
FC
2495=item Invalid character in charnames alias definition; marked by
2496S<<-- HERE> in '%s
225fb84f
KW
2497
2498(F) You tried to create a custom alias for a character name, with
2499the C<:alias> option to C<use charnames> and the specified character in
2500the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2501
c8028aa6
TC
2502=item Invalid \0 character in %s for %s: %s\0%s
2503
fa3234e3
FC
2504(W syscalls) Embedded \0 characters in pathnames or other system call
2505arguments produce a warning as of 5.20. The parts after the \0 were
2506formerly ignored by system calls.
c8028aa6 2507
e0e4a6e3 2508=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2509
2510(F) Only certain characters are valid for character names. The
2511indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2512
c635e13b
PP
2513=item Invalid conversion in %s: "%s"
2514
be771a83
GS
2515(W printf) Perl does not understand the given format conversion. See
2516L<perlfunc/sprintf>.
c635e13b 2517
e0e4a6e3
FC
2518=item Invalid escape in the specified encoding in regex; marked by
2519S<<-- HERE> in m/%s/
9e08bc66 2520
98d31c73 2521(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2522didn't correspond to a single character through the conversion
2523from the encoding specified by the encoding pragma.
98d31c73
FC
2524The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2525instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2526The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2527escape was discovered.
2528
8149aa9f
FC
2529=item Invalid hexadecimal number in \N{U+...}
2530
e0e4a6e3
FC
2531=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2532S<<-- HERE> in m/%s/
aec0ef10 2533
8149aa9f 2534(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2535number. Either it is empty, or you tried to use a character other than
25360 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2537
6651ba0b
FC
2538=item Invalid module name %s with -%c option: contains single ':'
2539
2540(F) The module argument to perl's B<-m> and B<-M> command-line options
2541cannot contain single colons in the module name, but only in the
2542arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2543B<-MFoo:Bar=baz> is not.
2544
2c7d6b9c
RGS
2545=item Invalid mro name: '%s'
2546
162a3e34
FC
2547(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2548where C<foo> is not a valid method resolution order (MRO). Currently,
2549the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2550a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2551
40e4140b
FC
2552=item Invalid negative number (%s) in chr
2553
2554(W utf8) You passed a negative number to C<chr>. Negative numbers are
2555not valid characters numbers, so it return the Unicode replacement
2556character (U+FFFD).
2557
6651ba0b
FC
2558=item invalid option -D%c, use -D'' to see choices
2559
8ff21bfe
FC
2560(S debugging) Perl was called with invalid debugger flags. Call perl
2561with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2562See also L<perlrun/-Dletters>.
6651ba0b 2563
e0e4a6e3 2564=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2565
2566(F) The range specified in a character class had a minimum character
7253e4e3
RK
2567greater than the maximum character. One possibility is that you forgot the
2568C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2569up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2570problem was discovered. See L<perlre>.
6df41af2 2571
d1573ac7 2572=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2573
2574(F) The range specified in the tr/// or y/// operator had a minimum
2575character greater than the maximum character. See L<perlop>.
2576
09bef843
SB
2577=item Invalid separator character %s in attribute list
2578
0120eecf 2579(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2580elements of an attribute list. If the previous attribute had a
2581parenthesised parameter list, perhaps that list was terminated too soon.
2582See L<attributes>.
09bef843 2583
b4581f09
JH
2584=item Invalid separator character %s in PerlIO layer specification %s
2585
2bfc5f71
FC
2586(W layer) When pushing layers onto the Perl I/O system, something other
2587than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2588If the previous attribute had a parenthesised parameter list, perhaps that
2589list was terminated too soon.
2590
2c86d456
DG
2591=item Invalid strict version format (%s)
2592
fa816bf3 2593(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2594A "strict" version number is a positive decimal number (integer or
2595decimal-fraction) without exponentiation or else a dotted-decimal
2596v-string with a leading 'v' character and at least three components.
a6485a24 2597The parenthesized text indicates which criteria were not met.
2c86d456
DG
2598See the L<version> module for more details on allowed version formats.
2599
49704364 2600=item Invalid type '%s' in %s
96e4d5b1 2601
49704364
LW
2602(F) The given character is not a valid pack or unpack type.
2603See L<perlfunc/pack>.
6728c851 2604
49704364 2605(W) The given character is not a valid pack or unpack type but used to be
75b44862 2606silently ignored.
96e4d5b1 2607
2c86d456
DG
2608=item Invalid version format (%s)
2609
fa816bf3 2610(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2611A "lax" version number is a positive decimal number (integer or
2612decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2613v-string. If the v-string has fewer than three components, it
2614must have a leading 'v' character. Otherwise, the leading 'v' is
2615optional. Both decimal and dotted-decimal versions may have a
2616trailing "alpha" component separated by an underscore character
2617after a fractional or dotted-decimal component. The parenthesized
2618text indicates which criteria were not met. See the L<version> module
2619for more details on allowed version formats.
46314c13 2620
798ae1b7
DG
2621=item Invalid version object
2622
fa816bf3
FC
2623(F) The internal structure of the version object was invalid.
2624Perhaps the internals were modified directly in some way or
2625an arbitrary reference was blessed into the "version" class.
798ae1b7 2626
cd209d9d 2627=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2628marked by S<<-- HERE> in m/%s/
675fa9ff 2629
cd209d9d 2630(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2631this context in a regular expression pattern should be an
2632indivisible token, with nothing intervening between the C<"(">
cd209d9d 2633and the C<"*">, but you separated them.
675fa9ff 2634
a0d0e21e
LW
2635=item ioctl is not implemented
2636
2637(F) Your machine apparently doesn't implement ioctl(), which is pretty
2638strange for a machine that supports C.
2639
c289d2f7
JH
2640=item ioctl() on unopened %s
2641
2642(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2643Check your control flow and number of arguments.
c289d2f7 2644
fe13d51d 2645=item IO layers (like '%s') unavailable
363c40c4
SB
2646
2647(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2648you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2649with 'useperlio'.
2650
80cbd5ad
JH
2651=item IO::Socket::atmark not implemented on this architecture
2652
2653(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2654neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2655
4f650b80 2656=item $* is no longer supported
b4581f09 2657
4f650b80 2658(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2659perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2660previous versions of perl the use of C<$*> enabled or disabled multi-line
2661matching within a string.
4fd19576
B
2662
2663Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2664modifiers. You can enable C</m> for a lexical scope (even a whole file)
2665with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2666then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2667
8ae1fe26
RGS
2668=item $# is no longer supported
2669
a58ac25e 2670(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2671perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2672should use the printf/sprintf functions instead.
8ae1fe26 2673
ccf3535a 2674=item '%s' is not a code reference
6ad11d81 2675
6903afa2
FC
2676(W overload) The second (fourth, sixth, ...) argument of
2677overload::constant needs to be a code reference. Either
2678an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2679
ccf3535a 2680=item '%s' is not an overloadable type
6ad11d81 2681
04a80ee0
RGS
2682(W overload) You tried to overload a constant type the overload package is
2683unaware of.
6ad11d81 2684
5a25739d
FC
2685=item -i used with no filenames on the command line, reading from STDIN
2686
2687(S inplace) The C<-i> option was passed on the command line, indicating
2688that the script is intended to edit files in place, but no files were
2689given. This is usually a mistake, since editing STDIN in place doesn't
2690make sense, and can be confusing because it can make perl look like
2691it is hanging when it is really just trying to read from STDIN. You
2692should either pass a filename to edit, or remove C<-i> from the command
2693line. See L<perlrun> for more details.
2694
aec0ef10 2695=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2696
2697(P) The regular expression parser is confused.
2698
0953b66b
FC
2699=item keys on reference is experimental
2700
0773cb3e
FC
2701(S experimental::autoderef) C<keys> with a scalar argument is experimental
2702and may change or be removed in a future Perl version. If you want to
2703take the risk of using this feature, simply disable this warning:
0953b66b 2704
d401967c 2705 no warnings "experimental::autoderef";
0953b66b 2706
a0d0e21e
LW
2707=item Label not found for "last %s"
2708
be771a83
GS
2709(F) You named a loop to break out of, but you're not currently in a loop
2710of that name, not even if you count where you were called from. See
2711L<perlfunc/last>.
a0d0e21e
LW
2712
2713=item Label not found for "next %s"
2714
2715(F) You named a loop to continue, but you're not currently in a loop of
2716that name, not even if you count where you were called from. See
2717L<perlfunc/last>.
2718
2719=item Label not found for "redo %s"
2720
2721(F) You named a loop to restart, but you're not currently in a loop of
2722that name, not even if you count where you were called from. See
2723L<perlfunc/last>.
2724
85ab1d1d 2725=item leaving effective %s failed
5ff3f7a4 2726
85ab1d1d 2727(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2728effective uids or gids failed.
2729
49704364
LW
2730=item length/code after end of string in unpack
2731
d7f8936a 2732(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2733length/code combination tried to obtain more data. This results in
2734an undefined value for the length. See L<perlfunc/pack>.
49704364 2735
25e26107 2736=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2737
0d46a4e7
FC
2738(W syntax) You used length() on either an array or a hash when you
2739probably wanted a count of the items.
e508c8a4
MH
2740
2741Array size can be obtained by doing:
2742
2743 scalar(@array);
2744
2745The number of items in a hash can be obtained by doing:
2746
2747 scalar(keys %hash);
2748
f0e67a1d
Z
2749=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2750
d4fe7078
RS
2751(F) An extension is attempting to insert text into the current parse
2752(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2753couldn't be part of the current input. This is an inherent pitfall
2754of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2755it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2756
2757=item Lexing code internal error (%s)
2758
2759(F) Lexing code supplied by an extension violated the lexer's API in a
2760detectable way.
2761
69282e91 2762=item listen() on closed socket %s
a0d0e21e 2763
be771a83
GS
2764(W closed) You tried to do a listen on a closed socket. Did you forget
2765to check the return value of your socket() call? See
2766L<perlfunc/listen>.
a0d0e21e 2767
6651ba0b
FC
2768=item List form of piped open not implemented
2769
2770(F) On some platforms, notably Windows, the three-or-more-arguments
2771form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2772Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2773
b35b96b6
JH
2774=item localtime(%f) failed
2775
2776(W overflow) You called C<localtime> with a number that it could not handle:
2777too large, too small, or NaN. The returned value is C<undef>.
2778
bcd05b94 2779=item localtime(%f) too large
8b56d6ff 2780
e9200be3 2781(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2782than it can reliably handle and C<localtime> probably returned the
6903afa2 2783wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2784not-a-number value).
2785
bcd05b94 2786=item localtime(%f) too small
fc003d4b 2787
e9200be3 2788(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2789than it can reliably handle and C<localtime> probably returned the
e7a1a147 2790wrong date.
8b56d6ff 2791
58e23c8d 2792=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2793
2794(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2795handle. This restriction may be eased in a future release.
2e50fd82 2796
b88df990
NC
2797=item Lost precision when %s %f by 1
2798
e63e8a91
FC
2799(W imprecision) The value you attempted to increment or decrement by one
2800is too large for the underlying floating point representation to store
2801accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2802warning because it has already switched from integers to floating point
2803when values are too large for integers, and now even floating point is
2804insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2805
93fad930 2806=item lstat() on filehandle%s
2f7da168
RK
2807
2808(W io) You tried to do an lstat on a filehandle. What did you mean
2809by that? lstat() makes sense only on filenames. (Perl did a fstat()
2810instead on the filehandle.)
2811
345d70e3 2812=item lvalue attribute %s already-defined subroutine
bb3abb05 2813
345d70e3
FC
2814(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2815attribute on or off on a Perl subroutine that is already defined
2816does not always work properly. It may or may not do what you
2817want, depending on what code is inside the subroutine, with exact
2818details subject to change between Perl versions. Only do this
2819if you really know what you are doing.
bb3abb05 2820
885ef6f5
GG
2821=item lvalue attribute ignored after the subroutine has been defined
2822
345d70e3
FC
2823(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2824subroutine an lvalue subroutine after it has been defined is
2825not permitted. To make the subroutine an lvalue subroutine,
2826add the lvalue attribute to the definition, or put the C<sub
2827foo :lvalue;> declaration before the definition.
2828
2829See also L<attributes.pm|attributes>.
885ef6f5 2830
6f1b3ab0
FC
2831=item Magical list constants are not supported
2832
2833(F) You assigned a magical array to a stash element, and then tried
2834to use the subroutine from the same slot. You are asking Perl to do
2835something it cannot do, details subject to change between Perl versions.
2836
2db62bbc 2837=item Malformed integer in [] in pack
49704364 2838
2db62bbc 2839(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2840are permitted. See L<perlfunc/pack>.
2841
2842=item Malformed integer in [] in unpack
2843
2db62bbc 2844(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2845are permitted. See L<perlfunc/pack>.
2846
6df41af2
GS
2847=item Malformed PERLLIB_PREFIX
2848
2849(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2850
2851 prefix1;prefix2
2852
2853or
6df41af2
GS
2854 prefix1 prefix2
2855
be771a83
GS
2856with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2857a builtin library search path, prefix2 is substituted. The error may
2858appear if components are not found, or are too long. See
fecfaeb8 2859"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2860
2f758a16
ST
2861=item Malformed prototype for %s: %s
2862
d37a9538
ST
2863(F) You tried to use a function with a malformed prototype. The
2864syntax of function prototypes is given a brief compile-time check for
2865obvious errors like invalid characters. A more rigorous check is run
2866when the function is called.
30d9c59b
Z
2867Perhaps the function's author was trying to write a subroutine signature
2868but didn't enable that feature first (C<use feature 'signatures'>),
2869so the signature was instead interpreted as a bad prototype.
2f758a16 2870
ba210ebe
JH
2871=item Malformed UTF-8 character (%s)
2872
4d6f11e5 2873(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2874encoding rules, even though it had the UTF8 flag on.
ba210ebe 2875
2575c402
JW
2876One possible cause is that you set the UTF8 flag yourself for data that
2877you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 28788-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2879
2880If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2881sequences are handled gracefully, but if you use C<:utf8>, the flag is
2882set without validating the data, possibly resulting in this error
2883message.
2884
2885See also L<Encode/"Handling Malformed Data">.
901b21bf 2886
107160e2
KW
2887=item Malformed UTF-8 character immediately after '%s'
2888
2889(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
2890encoding rules. The message prints out the properly encoded characters
2891just before the first bad one. If C<utf8> warnings are enabled, a
2892warning is generated that gives more details about the type of
2893malformation.
2894
bde9e88d 2895=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
2896
2897(F) The charnames handler returned malformed UTF-8.
2898
4a5d3a93
FC
2899=item Malformed UTF-8 string in '%c' format in unpack
2900
2901(F) You tried to unpack something that didn't comply with UTF-8 encoding
2902rules and perl was unable to guess how to make more progress.
2903
f337b084
TH
2904=item Malformed UTF-8 string in pack
2905
2906(F) You tried to pack something that didn't comply with UTF-8 encoding
2907rules and perl was unable to guess how to make more progress.
2908
2909=item Malformed UTF-8 string in unpack
2910
2911(F) You tried to unpack something that didn't comply with UTF-8 encoding
2912rules and perl was unable to guess how to make more progress.
2913
4a5d3a93 2914=item Malformed UTF-16 surrogate
f337b084 2915
4a5d3a93
FC
2916(F) Perl thought it was reading UTF-16 encoded character data but while
2917doing it Perl met a malformed Unicode surrogate.
2918
30d9c59b
Z
2919=item Mandatory parameter follows optional parameter
2920
2921(F) In a subroutine signature, you wrote something like "$a = undef,
2922$b", making an earlier parameter optional and a later one mandatory.
2923Parameters are filled from left to right, so it's impossible for the
2924caller to omit an earlier one and pass a later one. If you want to act
2925as if the parameters are filled from right to left, declare the rightmost
2926optional and then shuffle the parameters around in the subroutine's body.
2927
2d88a86a
KW
2928=item Matched non-Unicode code point 0x%X against Unicode property; may
2929not be portable
2930
2931(S non_unicode) Perl allows strings to contain a superset of
2932Unicode code points; each code point may be as large as what is storable
2933in an unsigned integer on your system, but these may not be accepted by
2934other languages/systems. This message occurs when you matched a string
2935containing such a code point against a regular expression pattern, and
2936the code point was matched against a Unicode property, C<\p{...}> or
2937C<\P{...}>. Unicode properties are only defined on Unicode code points,
2938so the result of this match is undefined by Unicode, but Perl (starting
2939in v5.20) treats non-Unicode code points as if they were typical
2940unassigned Unicode ones, and matched this one accordingly. Whether a
2941given property matches these code points or not is specified in
2942L<perluniprops/Properties accessible through \p{} and \P{}>.
2943
2944This message is suppressed (unless it has been made fatal) if it is
2945immaterial to the results of the match if the code point is Unicode or
2946not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
2947the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
2948Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
2949every code point except these 22.)
2950
2951Getting this message indicates that the outcome of the match arguably
2952should have been the opposite of what actually happened. If you think
2953that is the case, you may wish to make the C<non_unicode> warnings
2954category fatal; if you agree with Perl's decision, you may wish to turn
2955off this category.
2956
2957See L<perlunicode/Beyond Unicode code points> for more information.
2958
e0e4a6e3
FC
2959=item %s matches null string many times in regex; marked by S<<-- HERE> in
2960m/%s/
4a5d3a93
FC
2961
2962(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 2963regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 2964shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 2965See L<perlre>.
f337b084 2966
de42a5a9 2967=item Maximal count of pending signals (%u) exceeded
2563cec5 2968
6903afa2 2969(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
2970usually indicates that your operating system tried to deliver signals
2971too fast (with a very high priority), starving the perl process from
2972resources it would need to reach a point where it can process signals
6903afa2 2973safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 2974
25f58aea
PN
2975=item "%s" may clash with future reserved word
2976
2977(W) This warning may be due to running a perl5 script through a perl4
2978interpreter, especially if the word that is being warned about is
2979"use" or "my".
2980
0d2487cd 2981=item '%' may not be used in pack
6df41af2
GS
2982
2983(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
2984checksumming process loses information, and you can't go the other way.
2985See L<perlfunc/unpack>.
6df41af2 2986
a0d0e21e
LW
2987=item Method for operation %s not found in package %s during blessing
2988
2989(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 2990doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 2991
3cdd684c
TP
2992=item Method %s not permitted
2993
2994See Server error.
2995
a0d0e21e
LW
2996=item Might be a runaway multi-line %s string starting on line %d
2997
2998(S) An advisory indicating that the previous error may have been caused
2999by a missing delimiter on a string or pattern, because it eventually
3000ended earlier on the current line.
3001
3002=item Misplaced _ in number
3003
d4ced10d
JH
3004(W syntax) An underscore (underbar) in a numeric constant did not
3005separate two digits.
a0d0e21e 3006
7baa4690
HS
3007=item Missing argument in %s
3008
3664866e
AB
3009(W missing) You called a function with fewer arguments than other
3010arguments you supplied indicated would be needed.
3011
3012Currently only emitted when a printf-type format required more
3013arguments than were supplied, but might be used in the future for
3014other cases where we can statically determine that arguments to
3015functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3016
4077a6bc
AB
3017=item Redundant argument in %s
3018
3019(W redundant) You called a function with more arguments than other
3020arguments you supplied indicated would be needed. Currently only
3021emitted when a printf-type format required fewer arguments than were
3022supplied, but might be used in the future for e.g. L<perlfunc/pack>.
3023
9e81e6a1
RGS
3024=item Missing argument to -%c
3025
3026(F) The argument to the indicated command line switch must follow
3027immediately after the switch, without intervening spaces.
3028
ff3f963a 3029=item Missing braces on \N{}
423cee85 3030
e0e4a6e3 3031=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3032
4a2d328f 3033(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3034double-quotish context. This can also happen when there is a space
3035(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3036This modifier does not change the requirement that the brace immediately
3037follow the C<\N>.
423cee85 3038
f0a2b745
KW
3039=item Missing braces on \o{}
3040
3041(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3042
a0d0e21e
LW
3043=item Missing comma after first argument to %s function
3044
3045(F) While certain functions allow you to specify a filehandle or an
3046"indirect object" before the argument list, this ain't one of them.
3047
06eaf0bc
GS
3048=item Missing command in piped open
3049
be771a83
GS
3050(W pipe) You used the C<open(FH, "| command")> or
3051C<open(FH, "command |")> construction, but the command was missing or
3052blank.
06eaf0bc 3053
961ce445
RGS
3054=item Missing control char name in \c
3055
3056(F) A double-quoted string ended with "\c", without the required control
3057character name.
3058
591f5ca2
FC
3059=item Missing ']' in prototype for %s : %s
3060
bfe11873 3061(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3062
8767b1ab 3063=item Missing name in "%s sub"
6df41af2 3064
87444db5 3065(F) The syntax for lexically scoped subroutines requires that
be771a83 3066they have a name with which they can be found.
6df41af2
GS
3067
3068=item Missing $ on loop variable
3069
be771a83
GS
3070(F) Apparently you've been programming in B<csh> too much. Variables
3071are always mentioned with the $ in Perl, unlike in the shells, where it
3072can vary from one line to the next.
6df41af2 3073
cc507455 3074=item (Missing operator before %s?)
748a9306 3075
56da5a46
RGS
3076(S syntax) This is an educated guess made in conjunction with the message
3077"%s found where operator expected". Often the missing operator is a comma.
748a9306 3078
e0e4a6e3 3079=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3080
ff3f963a
KW
3081(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3082
4a68bf9d 3083=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3084
d32207c9
FC
3085(F) C<\N> has two meanings.
3086
3087The traditional one has it followed by a name enclosed in braces,
3088meaning the character (or sequence of characters) given by that
fa816bf3 3089name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3090double-quoted strings and regular expression patterns. In patterns,
3091it doesn't have the meaning an unescaped C<*> does.
3092
3093Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3094in patterns, namely to match a non-newline character. (This is short
3095for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3096
3097This can lead to some ambiguities. When C<\N> is not followed immediately
3098by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3099form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3100means to match the given quantity of non-newlines (in these examples,
31013; and 5 or more, respectively). In all other case, where there is a
3102C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3103
3104However, if there is no matching C<}>, Perl doesn't know if it was
3105mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3106If you meant the former, add the right brace; if you meant the latter,
3107escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3108
d98d5fff 3109=item Missing right curly or square bracket
a0d0e21e 3110
be771a83
GS
3111(F) The lexer counted more opening curly or square brackets than closing
3112ones. As a general rule, you'll find it's missing near the place you
3113were last editing.
a0d0e21e 3114
6df41af2
GS
3115=item (Missing semicolon on previous line?)
3116
56da5a46
RGS
3117(S syntax) This is an educated guess made in conjunction with the message
3118"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3119the previous line just because you saw this message.
3120
a0d0e21e
LW
3121=item Modification of a read-only value attempted
3122
3123(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3124constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3125catches that. But an easy way to do the same thing is:
3126
3127 sub mod { $_[0] = 1 }
3128 mod(2);
3129
3130Another way is to assign to a substr() that's off the end of the string.
3131
c5674021
PDF
3132Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3133is aliased to a constant in the look I<LIST>:
3134
b7e4ecc1
FC
3135 $x = 1;
3136 foreach my $n ($x, 2) {
3137 $n *= 2; # modifies the $x, but fails on attempt to
3138 } # modify the 2
c5674021 3139
7a4340ed 3140=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3141
3142(F) You tried to make an array value spring into existence, and the
3143subscript was probably negative, even counting from end of the array
3144backwards.
3145
7a4340ed 3146=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3147
be771a83
GS
3148(P) You tried to make a hash value spring into existence, and it
3149couldn't be created for some peculiar reason.
a0d0e21e
LW
3150
3151=item Module name must be constant
3152
3153(F) Only a bare module name is allowed as the first argument to a "use".
3154
be98fb35 3155=item Module name required with -%c option
6df41af2 3156
be98fb35
GS
3157(F) The C<-M> or C<-m> options say that Perl should load some module, but
3158you omitted the name of the module. Consult L<perlrun> for full details
3159about C<-M> and C<-m>.
6df41af2 3160
fe13d51d 3161=item More than one argument to '%s' open
ed9aa3b7 3162
6903afa2 3163(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3164can happen if you are trying to open a pipe to a command that takes a
3165list of arguments, but have forgotten to specify a piped open mode.
3166See L<perlfunc/open> for details.
3167
85396b18
FC
3168=item mprotect for COW string %p %u failed with %d
3169
3170(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3171L<perlguts/"Copy on Write">), but a shared string buffer
3172could not be made read-only.
3173
92951bce
FC
3174=item mprotect for %p %u failed with %d
3175
85396b18
FC
3176(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3177but an op tree could not be made read-only.
3178
3179=item mprotect RW for COW string %p %u failed with %d
3180
3181(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3182L<perlguts/"Copy on Write">), but a read-only shared string
3183buffer could not be made mutable.
3184
92951bce
FC
3185=item mprotect RW for %p %u failed with %d
3186
3187(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3188L<perlhacktips>), but a read-only op tree could not be made
3189mutable before freeing the ops.
92951bce 3190
a0d0e21e
LW
3191=item msg%s not implemented
3192
3193(F) You don't have System V message IPC on your system.
3194
3195=item Multidimensional syntax %s not supported
3196
75b44862
GS
3197(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3198They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3199
49704364 3200=item '/' must follow a numeric type in unpack
6df41af2 3201
49704364
LW
3202(F) You had an unpack template that contained a '/', but this did not
3203follow some unpack specification producing a numeric value.
3204See L<perlfunc/pack>.
6df41af2
GS
3205
3206=item "my sub" not yet implemented
3207
be771a83
GS
3208(F) Lexically scoped subroutines are not yet implemented. Don't try
3209that yet.
6df41af2 3210
5a25739d
FC
3211=item "my %s" used in sort comparison
3212
3213(W syntax) The package variables $a and $b are used for sort comparisons.
3214You used $a or $b in as an operand to the C<< <=> >> or C<cmp> operator inside a
3215sort comparison block, and the variable had earlier been declared as a
3216lexical variable. Either qualify the sort variable with the package
3217name, or rename the lexical variable.
3218
fd1b7234 3219=item "my" variable %s can't be in a package
6df41af2 3220
be771a83
GS
3221(F) Lexically scoped variables aren't in a package, so it doesn't make
3222sense to try to declare one with a package qualifier on the front. Use
3223local() if you want to localize a package variable.
09bef843 3224
8149aa9f
FC
3225=item Name "%s::%s" used only once: possible typo
3226
c59aba6c
FC
3227(W once) Typographical errors often show up as unique variable
3228names. If you had a good reason for having a unique name, then
3229just mention it again somehow to suppress the message. The C<our>
08a33b6b 3230declaration is also provided for this purpose.
c59aba6c 3231
66a1f5ec
FC
3232NOTE: This warning detects package symbols that have been used
3233only once. This means lexical variables will never trigger this
3234warning. It also means that all of the package variables $c, @c,
3235%c, as well as *c, &c, sub c{}, c(), and c (the filehandle or
c59aba6c
FC
3236format) are considered the same; if a program uses $c only once
3237but also uses any of the others it will not trigger this warning.
3238Symbols beginning with an underscore and symbols using special
3239identifiers (q.v. L<perldata>) are exempt from this warning.
8149aa9f 3240
e0e4a6e3 3241=item Need exactly 3 octal digits in regex; marked by S<<-- HERE> in m/%s/
0d0b4b3b
KW
3242
3243(F) Within S<C<(?[ ])>>, all constants interpreted as octal need to be
3244exactly 3 digits long. This helps catch some ambiguities. If your
3245constant is too short, add leading zeros, like
3246
3247 (?[ [ \078 ] ]) # Syntax error!
3248 (?[ [ \0078 ] ]) # Works
3249 (?[ [ \007 8 ] ]) # Clearer
3250
3251The maximum number this construct can express is C<\777>. If you
675fa9ff
FC
3252need a larger one, you need to use L<\o{}|perlrebackslash/Octal escapes> instead. If you meant
3253two separate things, you need to separate them:
0d0b4b3b
KW
3254
3255 (?[ [ \7776 ] ]) # Syntax error!
3256 (?[ [ \o{7776} ] ]) # One meaning
3257 (?[ [ \777 6 ] ]) # Another meaning
3258 (?[ [ \777 \006 ] ]) # Still another
3259
49704364
LW
3260=item Negative '/' count in unpack
3261
3262(F) The length count obtained from a length/code unpack operation was
3263negative. See L<perlfunc/pack>.
3264
a0d0e21e
LW
3265=item Negative length
3266
be771a83
GS
3267(F) You tried to do a read/write/send/recv operation with a buffer
3268length that is less than 0. This is difficult to imagine.
a0d0e21e 3269
ed9aa3b7
SG
3270=item Negative offset to vec in lvalue context
3271
3272(F) When C<vec> is called in an lvalue context, the second argument must be
3273greater than or equal to zero.
3274
b3211734
KW
3275=item Negative repeat count does nothing
3276
3277(W numeric) You tried to execute the
3278L<C<x>|perlop/Multiplicative Operators> repetition operator fewer than 0
3279times, which doesn't make sense.
3280
e0e4a6e3 3281=item Nested quantifiers in regex; marked by S<<-- HERE> in m/%s/
a0d0e21e 3282
6903afa2 3283(F) You can't quantify a quantifier without intervening parentheses.
e0e4a6e3 3284So things like ** or +* or ?* are illegal. The S<<-- HERE> shows
9e3ec65c 3285whereabouts in the regular expression the problem was discovered.
a0d0e21e 3286
7253e4e3 3287Note that the minimal matching quantifiers, C<*?>, C<+?>, and
be771a83 3288C<??> appear to be nested quantifiers, but aren't. See L<perlre>.
a0d0e21e 3289
6df41af2 3290=item %s never introduced
a0d0e21e 3291
be771a83
GS
3292(S internal) The symbol in question was declared but somehow went out of
3293scope before it could possibly have been used.
a0d0e21e 3294
2c7d6b9c
RGS
3295=item next::method/next::can/maybe::next::method cannot find enclosing method
3296
3297(F) C<next::method> needs to be called within the context of a
3298real method in a real package, and it could not find such a context.
3299See L<mro>.
3300
5a25739d 3301=item \N in a character class must be a named character: \N{...} in regex;
e0e4a6e3 3302marked by S<<-- HERE> in m/%s/
5a25739d 3303
32a77fbe
FC
3304(F) The new (as of Perl 5.12) meaning of C<\N> as C<[^\n]> is not valid in a
3305bracketed character class, for the same reason that C<.> in a character
3306class loses its specialness: it matches almost everything, which is
3307probably not what you want.
5a25739d 3308
0b4ce96d 3309=item \N{} in character class restricted to one character in regex; marked