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remove obsolete panic from die_unwind()
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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
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53=item Aliasing via reference is experimental
54
55(S experimental::refaliasing) This warning is emitted if you use
56a reference constructor on the left-hand side of an assignment to
57alias one variable to another. Simply suppress the warning if you
58want to use the feature, but know that in doing so you are taking
59the risk of using an experimental feature which may change or be
60removed in a future Perl version:
61
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
64 \$x = \$y;
65
de42a5a9 66=item Allocation too large: %x
a0d0e21e 67
6df41af2 68(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 69
04f74579 70=item '%c' allowed only after types %s in %s
ef54e1a4 71
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72(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73after certain types. See L<perlfunc/pack>.
ef54e1a4 74
6df41af2 75=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 76
75b44862 77(W ambiguous) A subroutine you have declared has the same name as a Perl
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78keyword, and you have used the name without qualification for calling
79one or the other. Perl decided to call the builtin because the
80subroutine is not imported.
43192e07 81
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82To force interpretation as a subroutine call, either put an ampersand
83before the subroutine name, or qualify the name with its package.
84Alternatively, you can import the subroutine (or pretend that it's
85imported with the C<use subs> pragma).
43192e07 86
6df41af2 87To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 88on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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89to be an object method (see L<perlsub/"Subroutine Attributes"> or
90L<attributes>).
43192e07 91
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92=item Ambiguous range in transliteration operator
93
94(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
95all. To include a C<-> character in a transliteration, put it either
96first or last. (In the past, C<tr/a-z-0//> was synonymous with
97C<tr/a-y//>, which was probably not what you would have expected.)
98
6df41af2 99=item Ambiguous use of %s resolved as %s
43192e07 100
7c7af292 101(S ambiguous) You said something that may not be interpreted the way
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102you thought. Normally it's pretty easy to disambiguate it by supplying
103a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 104
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105=item Ambiguous use of -%s resolved as -&%s()
106
107(S ambiguous) You wrote something like C<-foo>, which might be the
108string C<"-foo">, or a call to the function C<foo>, negated. If you meant
109the string, just write C<"-foo">. If you meant the function call,
110write C<-foo()>.
111
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112=item Ambiguous use of %c resolved as operator %c
113
7c7af292 114(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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115bitwise and, and multiplication) I<and> initial special characters
116(denoting hashes, subroutines and typeglobs), and you said something
117like C<*foo * foo> that might be interpreted as either of them. We
118assumed you meant the infix operator, but please try to make it more
119clear -- in the example given, you might write C<*foo * foo()> if you
120really meant to multiply a glob by the result of calling a function.
d8225693 121
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122=item Ambiguous use of %c{%s} resolved to %c%s
123
124(W ambiguous) You wrote something like C<@{foo}>, which might be
125asking for the variable C<@foo>, or it might be calling a function
126named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 127the variable, you can just write C<@foo>. If you wanted to call the
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128function, write C<@{foo()}> ... or you could just not have a variable
129and a function with the same name, and save yourself a lot of trouble.
130
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131=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
132
133=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 134
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135(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
136the name of a Perl keyword), which might be looking for element number
1372 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
138might have meant to pass an anonymous arrayref to the function named
139foo, and then do a scalar deref on the value it returns. If you meant
140that, write C<${foo([2])}>.
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141
142In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
143to disambiguate between array subscripts and character classes.
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144C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
145by the character class C<[2345]>. If an array subscript is what you
146want, you can avoid the warning by changing C</${length[2345]}/> to the
147unsightly C</${\$length[2345]}/>, by renaming your array to something
148that does not coincide with a built-in keyword, or by simply turning
149off warnings with C<no warnings 'ambiguous';>.
4da60377 150
6df41af2 151=item '|' and '<' may not both be specified on command line
a0d0e21e 152
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153(F) An error peculiar to VMS. Perl does its own command line
154redirection, and found that STDIN was a pipe, and that you also tried to
155redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 156
6df41af2 157=item '|' and '>' may not both be specified on command line
1028017a 158
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159(F) An error peculiar to VMS. Perl does its own command line
160redirection, and thinks you tried to redirect stdout both to a file and
161into a pipe to another command. You need to choose one or the other,
162though nothing's stopping you from piping into a program or Perl script
163which 'splits' output into two streams, such as
1028017a 164
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165 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
166 while (<STDIN>) {
167 print;
168 print OUT;
169 }
170 close OUT;
c9f97d15 171
6df41af2 172=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 173
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174(W misc) The pattern match (C<//>), substitution (C<s///>), and
175transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 176one of them to an array or a hash, it will convert the array or hash to
ac036724 177a scalar value (the length of an array, or the population info of a
178hash) and then work on that scalar value. This is probably not what
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179you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
180alternatives.
eb6e2d6f 181
6df41af2 182=item Arg too short for msgsnd
76cd736e 183
6df41af2 184(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 185
f86702cc 186=item Argument "%s" isn't numeric%s
a0d0e21e 187
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188(W numeric) The indicated string was fed as an argument to an operator
189that expected a numeric value instead. If you're fortunate the message
190will identify which operator was so unfortunate.
a0d0e21e 191
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192Note that for the C<Inf> and C<NaN> (infinity and not-a-number) the
193definition of "numeric" is somewhat unusual: the strings themselves
194(like "Inf") are considered numeric, and anything following them is
195considered non-numeric.
196
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197=item Argument list not closed for PerlIO layer "%s"
198
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199(W layer) When pushing a layer with arguments onto the Perl I/O
200system you forgot the ) that closes the argument list. (Layers
201take care of transforming data between external and internal
202representations.) Perl stopped parsing the layer list at this
203point and did not attempt to push this layer. If your program
204didn't explicitly request the failing operation, it may be the
205result of the value of the environment variable PERLIO.
b4581f09 206
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207=item Argument "%s" treated as 0 in increment (++)
208
209(W numeric) The indicated string was fed as an argument to the C<++>
210operator which expects either a number or a string matching
211C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
212Auto-decrement> for details.
213
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214=item assertion botched: %s
215
21b5e840 216(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 217
0eacef8e 218=item Assertion %s failed: file "%s", line %d
a0d0e21e 219
21b5e840 220(X) A general assertion failed. The file in question must be examined.
a0d0e21e 221
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222=item Assigned value is not a reference
223
224(F) You tried to assign something that was not a reference to an lvalue
225reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
226C<\$x = \$y>.
227
228=item Assigned value is not %s reference
229
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230(F) You tried to assign a reference to a reference constructor, but the
231two references were not of the same type. You cannot alias a scalar to
232an array, or an array to a hash; the two types must match.
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233
234 \$x = \@y; # error
235 \@x = \%y; # error
236 $y = [];
237 \$x = $y; # error; did you mean \$y?
238
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239=item Assigning non-zero to $[ is no longer possible
240
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241(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
242the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 243
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244=item Assignment to both a list and a scalar
245
246(F) If you assign to a conditional operator, the 2nd and 3rd arguments
247must either both be scalars or both be lists. Otherwise Perl won't
248know which context to supply to the right side.
249
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250=item <> at require-statement should be quotes
251
252(F) You wrote C<< require <file> >> when you should have written
253C<require 'file'>.
254
2393f1b9 255=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 256
49293501 257(F) The failing code has attempted to get or set a key which is not in
2393f1b9 258the current set of allowed keys of a restricted hash.
49293501 259
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260=item Attempt to bless into a freed package
261
262(F) You wrote C<bless $foo> with one argument after somehow causing
263the current package to be freed. Perl cannot figure out what to
264do, so it throws up in hands in despair.
265
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266=item Attempt to bless into a reference
267
268(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 269the name of the package to bless the resulting object into. You've
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270supplied instead a reference to something: perhaps you wrote
271
272 bless $self, $proto;
273
274when you intended
275
276 bless $self, ref($proto) || $proto;
277
278If you actually want to bless into the stringified version
279of the reference supplied, you need to stringify it yourself, for
280example by:
281
282 bless $self, "$proto";
283
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284=item Attempt to clear deleted array
285
286(S debugging) An array was assigned to when it was being freed.
287Freed values are not supposed to be visible to Perl code. This
288can also happen if XS code calls C<av_clear> from a custom magic
289callback on the array.
290
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291=item Attempt to delete disallowed key '%s' from a restricted hash
292
293(F) The failing code attempted to delete from a restricted hash a key
294which is not in its key set.
295
296=item Attempt to delete readonly key '%s' from a restricted hash
297
298(F) The failing code attempted to delete a key whose value has been
299declared readonly from a restricted hash.
300
de42a5a9 301=item Attempt to free non-arena SV: 0x%x
a0d0e21e 302
f84fe999 303(S internal) All SV objects are supposed to be allocated from arenas
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304that will be garbage collected on exit. An SV was discovered to be
305outside any of those arenas.
a0d0e21e 306
12578ffb 307=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 308
f84fe999 309(S internal) Perl maintains a reference-counted internal table of
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310strings to optimize the storage and access of hash keys and other
311strings. This indicates someone tried to decrement the reference count
312of a string that can no longer be found in the table.
bbce6d69 313
7d5b40b4 314=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 315
f84fe999 316(S debugging) Mortalized values are supposed to be freed by the
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317free_tmps() routine. This indicates that something else is freeing the
318SV before the free_tmps() routine gets a chance, which means that the
319free_tmps() routine will be freeing an unreferenced scalar when it does
320try to free it.
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321
322=item Attempt to free unreferenced glob pointers
323
f84fe999 324(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 325
7d5b40b4 326=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 327
8f7e4d2c 328(S internal) Perl went to decrement the reference count of a scalar to
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329see if it would go to 0, and discovered that it had already gone to 0
330earlier, and should have been freed, and in fact, probably was freed.
331This could indicate that SvREFCNT_dec() was called too many times, or
332that SvREFCNT_inc() was called too few times, or that the SV was
333mortalized when it shouldn't have been, or that memory has been
334corrupted.
a0d0e21e 335
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336=item Attempt to pack pointer to temporary value
337
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338(W pack) You tried to pass a temporary value (like the result of a
339function, or a computed expression) to the "p" pack() template. This
340means the result contains a pointer to a location that could become
341invalid anytime, even before the end of the current statement. Use
342literals or global values as arguments to the "p" pack() template to
343avoid this warning.
84902520 344
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345=item Attempt to reload %s aborted.
346
347(F) You tried to load a file with C<use> or C<require> that failed to
348compile once already. Perl will not try to compile this file again
349unless you delete its entry from %INC. See L<perlfunc/require> and
350L<perlvar/%INC>.
351
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352=item Attempt to set length of freed array
353
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354(W misc) You tried to set the length of an array which has
355been freed. You can do this by storing a reference to the
356scalar representing the last index of an array and later
357assigning through that reference. For example
1b20cd17
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358
359 $r = do {my @a; \$#a};
360 $$r = 503
361
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362=item Attempt to use reference as lvalue in substr
363
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364(W substr) You supplied a reference as the first argument to substr()
365used as an lvalue, which is pretty strange. Perhaps you forgot to
366dereference it first. See L<perlfunc/substr>.
b7a902f4 367
c32124fe
NC
368=item Attribute "locked" is deprecated
369
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370(D deprecated) You have used the attributes pragma to modify the
371"locked" attribute on a code reference. The :locked attribute is
372obsolete, has had no effect since 5005 threads were removed, and
373will be removed in a future release of Perl 5.
c32124fe 374
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375=item Attribute prototype(%s) discards earlier prototype attribute in same sub
376
377(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
378example. Since each sub can only have one prototype, the earlier
379declaration(s) are discarded while the last one is applied.
380
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381=item Attribute "unique" is deprecated
382
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383(D deprecated) You have used the attributes pragma to modify
384the "unique" attribute on an array, hash or scalar reference.
385The :unique attribute has had no effect since Perl 5.8.8, and
386will be removed in a future release of Perl 5.
f1a3ce43 387
ccce04a4
FC
388=item av_reify called on tied array
389
390(S debugging) This indicates that something went wrong and Perl got I<very>
391confused about C<@_> or C<@DB::args> being tied.
392
de42a5a9 393=item Bad arg length for %s, is %u, should be %d
a0d0e21e 394
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395(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
396or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 397S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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398S<sizeof(struct shmid_ds *)>.
399
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400=item Bad evalled substitution pattern
401
496a33f5 402(F) You've used the C</e> switch to evaluate the replacement for a
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403substitution, but perl found a syntax error in the code to evaluate,
404most likely an unexpected right brace '}'.
405
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406=item Bad filehandle: %s
407
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408(F) A symbol was passed to something wanting a filehandle, but the
409symbol has no filehandle associated with it. Perhaps you didn't do an
410open(), or did it in another package.
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411
412=item Bad free() ignored
413
be771a83 414(S malloc) An internal routine called free() on something that had never
fa816bf3 415been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 416setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 417
9ea8bc6d 418This message can be seen quite often with DB_File on systems with "hard"
6903afa2 419dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 420which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 421
aa689395
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422=item Bad hash
423
424(P) One of the internal hash routines was passed a null HV pointer.
425
6df41af2
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426=item Badly placed ()'s
427
428(A) You've accidentally run your script through B<csh> instead
429of Perl. Check the #! line, or manually feed your script into
430Perl yourself.
431
a7cb8dae 432=item Bad name after %s
a0d0e21e 433
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434(F) You started to name a symbol by using a package prefix, and then
435didn't finish the symbol. In particular, you can't interpolate outside
436of quotes, so
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437
438 $var = 'myvar';
439 $sym = mypack::$var;
440
441is not the same as
442
443 $var = 'myvar';
444 $sym = "mypack::$var";
445
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JV
446=item Bad plugin affecting keyword '%s'
447
448(F) An extension using the keyword plugin mechanism violated the
449plugin API.
450
4ad56ec9
IZ
451=item Bad realloc() ignored
452
6903afa2
FC
453(S malloc) An internal routine called realloc() on something that
454had never been malloc()ed in the first place. Mandatory, but can
455be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 456
a0d0e21e
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457=item Bad symbol for array
458
459(P) An internal request asked to add an array entry to something that
460wasn't a symbol table entry.
461
4df3f177
SP
462=item Bad symbol for dirhandle
463
464(P) An internal request asked to add a dirhandle entry to something
465that wasn't a symbol table entry.
466
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467=item Bad symbol for filehandle
468
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469(P) An internal request asked to add a filehandle entry to something
470that wasn't a symbol table entry.
a0d0e21e
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471
472=item Bad symbol for hash
473
474(P) An internal request asked to add a hash entry to something that
475wasn't a symbol table entry.
476
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FC
477=item Bad symbol for scalar
478
479(P) An internal request asked to add a scalar entry to something that
480wasn't a symbol table entry.
481
34d09196
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482=item Bareword found in conditional
483
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484(W bareword) The compiler found a bareword where it expected a
485conditional, which often indicates that an || or && was parsed as part
486of the last argument of the previous construct, for example:
34d09196
GS
487
488 open FOO || die;
489
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490It may also indicate a misspelled constant that has been interpreted as
491a bareword:
34d09196
GS
492
493 use constant TYPO => 1;
494 if (TYOP) { print "foo" }
495
496The C<strict> pragma is useful in avoiding such errors.
497
6df41af2
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498=item Bareword "%s" not allowed while "strict subs" in use
499
500(F) With "strict subs" in use, a bareword is only allowed as a
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501subroutine identifier, in curly brackets or to the left of the "=>"
502symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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503
504=item Bareword "%s" refers to nonexistent package
505
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506(W bareword) You used a qualified bareword of the form C<Foo::>, but the
507compiler saw no other uses of that namespace before that point. Perhaps
508you need to predeclare a package?
6df41af2 509
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510=item BEGIN failed--compilation aborted
511
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512(F) An untrapped exception was raised while executing a BEGIN
513subroutine. Compilation stops immediately and the interpreter is
514exited.
a0d0e21e 515
68dc0745
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516=item BEGIN not safe after errors--compilation aborted
517
518(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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519implies a C<BEGIN {}>) after one or more compilation errors had already
520occurred. Since the intended environment for the C<BEGIN {}> could not
521be guaranteed (due to the errors), and since subsequent code likely
522depends on its correct operation, Perl just gave up.
68dc0745 523
c782d7ee 524=item \%d better written as $%d
6df41af2 525
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526(W syntax) Outside of patterns, backreferences live on as variables.
527The use of backslashes is grandfathered on the right-hand side of a
528substitution, but stylistically it's better to use the variable form
529because other Perl programmers will expect it, and it works better if
530there are more than 9 backreferences.
6df41af2 531
252aa082
JH
532=item Binary number > 0b11111111111111111111111111111111 non-portable
533
e476b1b5 534(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
535(4294967295) and therefore non-portable between systems. See
536L<perlport> for more on portability concerns.
252aa082 537
69282e91 538=item bind() on closed socket %s
a0d0e21e 539
be771a83
GS
540(W closed) You tried to do a bind on a closed socket. Did you forget to
541check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 542
c289d2f7
JH
543=item binmode() on closed filehandle %s
544
545(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 546Check your control flow and number of arguments.
c289d2f7 547
c5a0f51a
JH
548=item Bit vector size > 32 non-portable
549
e476b1b5 550(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 551
043c750c 552=item Bizarre copy of %s
4633a7c4 553
be771a83 554(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 555copiable.
4633a7c4 556
5a25739d
FC
557=item Bizarre SvTYPE [%d]
558
434f489b 559(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
560encountered an invalid data type.
561
b927b7e9 562=item Both or neither range ends should be Unicode in regex; marked by
6e8a73f2 563S<<-- HERE> in m/%s/
b927b7e9
KW
564
565(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
566
567In a bracketed character class in a regular expression pattern, you
568had a range which has exactly one end of it specified using C<\N{}>, and
569the other end is specified using a non-portable mechanism. Perl treats
570the range as a Unicode range, that is, all the characters in it are
571considered to be the Unicode characters, and which may be different code
572points on some platforms Perl runs on. For example, C<[\N{U+06}-\x08]>
573is treated as if you had instead said C<[\N{U+06}-\N{U+08}]>, that is it
574matches the characters whose code points in Unicode are 6, 7, and 8.
575But that C<\x08> might indicate that you meant something different, so
576the warning gets raised.
577
f675dbe5
CB
578=item Buffer overflow in prime_env_iter: %s
579
be771a83
GS
580(W internal) A warning peculiar to VMS. While Perl was preparing to
581iterate over %ENV, it encountered a logical name or symbol definition
582which was too long, so it was truncated to the string shown.
f675dbe5 583
a0d0e21e
LW
584=item Callback called exit
585
4929bf7b 586(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
587exited by calling exit.
588
6df41af2 589=item %s() called too early to check prototype
f675dbe5 590
be771a83
GS
591(W prototype) You've called a function that has a prototype before the
592parser saw a definition or declaration for it, and Perl could not check
593that the call conforms to the prototype. You need to either add an
594early prototype declaration for the subroutine in question, or move the
595subroutine definition ahead of the call to get proper prototype
596checking. Alternatively, if you are certain that you're calling the
597function correctly, you may put an ampersand before the name to avoid
598the warning. See L<perlsub>.
f675dbe5 599
56feebad
FC
600=item Calling POSIX::%s() is deprecated
601
602(D deprecated) You called a function whose use is deprecated. See
603the function's name in L<POSIX> for details.
604
0c7df902
JH
605=item Cannot chr %f
606
607(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
608
5dee29d4 609=item Cannot compress %f in pack
0c7df902 610
5dee29d4
JH
611(F) You tried compressing an infinity or not-a-number as an unsigned
612integer with BER, which makes no sense.
0c7df902 613
49704364 614=item Cannot compress integer in pack
0258719b 615
717feafc
JH
616(F) An argument to pack("w",...) was too large to compress.
617The BER compressed integer format can only be used with positive
618integers, and you attempted to compress a very large number (> 1e308).
619See L<perlfunc/pack>.
0258719b 620
49704364 621=item Cannot compress negative numbers in pack
0258719b
NC
622
623(F) An argument to pack("w",...) was negative. The BER compressed integer
624format can only be used with positive integers. See L<perlfunc/pack>.
625
5c1f4d79
NC
626=item Cannot convert a reference to %s to typeglob
627
6903afa2
FC
628(F) You manipulated Perl's symbol table directly, stored a reference
629in it, then tried to access that symbol via conventional Perl syntax.
630The access triggers Perl to autovivify that typeglob, but it there is
631no legal conversion from that type of reference to a typeglob.
5c1f4d79 632
4040665a 633=item Cannot copy to %s
ba2fdce6
NC
634
635(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 636be directly assigned to.
ba2fdce6 637
b5d97229
RGS
638=item Cannot find encoding "%s"
639
640(S io) You tried to apply an encoding that did not exist to a filehandle,
641either with open() or binmode().
642
0c7df902
JH
643=item Cannot pack %f with '%c'
644
5dee29d4 645(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
646which makes no sense.
647
648=item Cannot printf %f with '%c'
649
650(F) You tried printing an infinity or not-a-number as a character (%c),
651which makes no sense. Maybe you meant '%s', or just stringifying it?
652
7355df7e
FC
653=item Cannot set tied @DB::args
654
655(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
656is not supported. (Before this error was added, it used to crash.)
657
ce65bc73
FC
658=item Cannot tie unreifiable array
659
660(P) You somehow managed to call C<tie> on an array that does not
661keep a reference count on its arguments and cannot be made to
662do so. Such arrays are not even supposed to be accessible to
663Perl code, but are only used internally.
664
46e58bd2
AC
665=item Cannot yet reorder sv_catpvfn() arguments from va_list
666
667(F) Some XS code tried to use C<sv_catpvfn()> or a related function with a
668format string that specifies explicit indexes for some of the elements, and
669using a C-style variable-argument list (a C<va_list>). This is not currently
670supported. XS authors wanting to do this must instead construct a C array of
671C<SV*> scalars containing the arguments.
672
96ebfdd7
RK
673=item Can only compress unsigned integers in pack
674
675(F) An argument to pack("w",...) was not an integer. The BER compressed
676integer format can only be used with positive integers, and you attempted
677to compress something else. See L<perlfunc/pack>.
678
a0d0e21e
LW
679=item Can't bless non-reference value
680
681(F) Only hard references may be blessed. This is how Perl "enforces"
682encapsulation of objects. See L<perlobj>.
683
dc57907a
RGS
684=item Can't "break" in a loop topicalizer
685
0d863452 686(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 687a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
688
689=item Can't "break" outside a given block
dc57907a 690
0d863452
RH
691(F) You called C<break>, but you're not inside a C<given> block.
692
6df41af2
GS
693=item Can't call method "%s" on an undefined value
694
695(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
696object reference or package name contains an undefined value. Something
697like this will reproduce the error:
6df41af2
GS
698
699 $BADREF = undef;
700 process $BADREF 1,2,3;
701 $BADREF->process(1,2,3);
702
a0d0e21e
LW
703=item Can't call method "%s" on unblessed reference
704
54310121 705(F) A method call must know in what package it's supposed to run. It
be771a83
GS
706ordinarily finds this out from the object reference you supply, but you
707didn't supply an object reference in this case. A reference isn't an
708object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
709
710=item Can't call method "%s" without a package or object reference
711
712(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
713object reference or package name contains an expression that returns a
714defined value which is neither an object reference nor a package name.
72b5445b
GS
715Something like this will reproduce the error:
716
717 $BADREF = 42;
718 process $BADREF 1,2,3;
719 $BADREF->process(1,2,3);
720
dfe378f1
FC
721=item Can't call mro_isa_changed_in() on anonymous symbol table
722
723(P) Perl got confused as to whether a hash was a plain hash or a
724symbol table hash when trying to update @ISA caches.
725
2bf7e7b2
FC
726=item Can't call mro_method_changed_in() on anonymous symbol table
727
728(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
729not attached to the symbol table.
730
a0d0e21e
LW
731=item Can't chdir to %s
732
f703fc96 733(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
734that you can chdir to, possibly because it doesn't exist.
735
0545a864 736=item Can't check filesystem of script "%s" for nosuid
104d25b7 737
be771a83
GS
738(P) For some reason you can't check the filesystem of the script for
739nosuid.
104d25b7 740
22e74366 741=item Can't coerce %s to %s in %s
a0d0e21e
LW
742
743(F) Certain types of SVs, in particular real symbol table entries
55497cff 744(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
745say things like:
746
747 *foo += 1;
748
749You CAN say
750
751 $foo = *foo;
752 $foo += 1;
753
754but then $foo no longer contains a glob.
755
0d863452 756=item Can't "continue" outside a when block
dc57907a 757
0d863452
RH
758(F) You called C<continue>, but you're not inside a C<when>
759or C<default> block.
760
a0d0e21e
LW
761=item Can't create pipe mailbox
762
be771a83
GS
763(P) An error peculiar to VMS. The process is suffering from exhausted
764quotas or other plumbing problems.
a0d0e21e 765
eb64745e
GS
766=item Can't declare %s in "%s"
767
30c282f6
NC
768(F) Only scalar, array, and hash variables may be declared as "my", "our" or
769"state" variables. They must have ordinary identifiers as names.
a0d0e21e 770
fc7debfb
FC
771=item Can't "default" outside a topicalizer
772
773(F) You have used a C<default> block that is neither inside a
774C<foreach> loop nor a C<given> block. (Note that this error is
775issued on exit from the C<default> block, so you won't get the
776error if you use an explicit C<continue>.)
777
a2162cd9
FC
778=item Can't do inplace edit: %s is not a regular file
779
780(S inplace) You tried to use the B<-i> switch on a special file, such as
781a file in /dev, a FIFO or an uneditable directory. The file was ignored.
782
783=item Can't do inplace edit on %s: %s
784
785(S inplace) The creation of the new file failed for the indicated
786reason.
787
788=item Can't do inplace edit without backup
789
790(F) You're on a system such as MS-DOS that gets confused if you try
791reading from a deleted (but still opened) file. You have to say
792C<-i.bak>, or some such.
793
794=item Can't do inplace edit: %s would not be unique
795
796(S inplace) Your filesystem does not support filenames longer than 14
797characters and Perl was unable to create a unique filename during
798inplace editing with the B<-i> switch. The file was ignored.
799
ab0b796c
KW
800=item Can't do %s("%s") on non-UTF-8 locale; resolved to "%s".
801
802(W locale) You are 1) running under "C<use locale>"; 2) the current
803locale is not a UTF-8 one; 3) you tried to do the designated case-change
804operation on the specified Unicode character; and 4) the result of this
805operation would mix Unicode and locale rules, which likely conflict.
806Mixing of different rule types is forbidden, so the operation was not
807done; instead the result is the indicated value, which is the best
808available that uses entirely Unicode rules. That turns out to almost
809always be the original character, unchanged.
810
811It is generally a bad idea to mix non-UTF-8 locales and Unicode, and
812this issue is one of the reasons why. This warning is raised when
813Unicode rules would normally cause the result of this operation to
814contain a character that is in the range specified by the locale,
8150..255, and hence is subject to the locale's rules, not Unicode's.
816
817If you are using locale purely for its characteristics related to things
818like its numeric and time formatting (and not C<LC_CTYPE>), consider
819using a restricted form of the locale pragma (see L<perllocale/The "use
820locale" pragma>) like "S<C<use locale ':not_characters'>>".
821
822Note that failed case-changing operations done as a result of
823case-insensitive C</i> regular expression matching will show up in this
824warning as having the C<fc> operation (as that is what the regular
825expression engine calls behind the scenes.)
826
a0d0e21e
LW
827=item Can't do waitpid with flags
828
be771a83
GS
829(F) This machine doesn't have either waitpid() or wait4(), so only
830waitpid() without flags is emulated.
a0d0e21e 831
a0d0e21e
LW
832=item Can't emulate -%s on #! line
833
be771a83
GS
834(F) The #! line specifies a switch that doesn't make sense at this
835point. For example, it'd be kind of silly to put a B<-x> on the #!
836line.
a0d0e21e 837
1109a392
MHM
838=item Can't %s %s-endian %ss on this platform
839
840(F) Your platform's byte-order is neither big-endian nor little-endian,
841or it has a very strange pointer size. Packing and unpacking big- or
842little-endian floating point values and pointers may not be possible.
843See L<perlfunc/pack>.
844
a0d0e21e
LW
845=item Can't exec "%s": %s
846
d1be9408 847(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
848named program for the indicated reason. Typical reasons include: the
849permissions were wrong on the file, the file wasn't found in
850C<$ENV{PATH}>, the executable in question was compiled for another
851architecture, or the #! line in a script points to an interpreter that
852can't be run for similar reasons. (Or maybe your system doesn't support
853#! at all.)
a0d0e21e
LW
854
855=item Can't exec %s
856
be771a83
GS
857(F) Perl was trying to execute the indicated program for you because
858that's what the #! line said. If that's not what you wanted, you may
859need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
860
861=item Can't execute %s
862
be771a83
GS
863(F) You used the B<-S> switch, but the copies of the script to execute
864found in the PATH did not have correct permissions.
2a92aaa0 865
6df41af2 866=item Can't find an opnumber for "%s"
2a92aaa0 867
be771a83
GS
868(F) A string of a form C<CORE::word> was given to prototype(), but there
869is no builtin with the name C<word>.
6df41af2
GS
870
871=item Can't find label %s
872
be771a83
GS
873(F) You said to goto a label that isn't mentioned anywhere that it's
874possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
875
876=item Can't find %s on PATH
877
be771a83
GS
878(F) You used the B<-S> switch, but the script to execute could not be
879found in the PATH.
a0d0e21e 880
6df41af2 881=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 882
be771a83
GS
883(F) You used the B<-S> switch, but the script to execute could not be
884found in the PATH, or at least not with the correct permissions. The
885script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
886
887=item Can't find string terminator %s anywhere before EOF
888
be771a83
GS
889(F) Perl strings can stretch over multiple lines. This message means
890that the closing delimiter was omitted. Because bracketed quotes count
891nesting levels, the following is missing its final parenthesis:
a0d0e21e 892
fb73857a
PP
893 print q(The character '(' starts a side comment.);
894
97b3d10f 895If you're getting this error from a here-document, you may have
b6b8cb97
FC
896included unseen whitespace before or after your closing tag or there
897may not be a linebreak after it. A good programmer's editor will have
898a way to help you find these characters (or lack of characters). See
899L<perlop> for the full details on here-documents.
a0d0e21e 900
660a4616
ST
901=item Can't find Unicode property definition "%s"
902
29f52644
KW
903=item Can't find Unicode property definition "%s" in regex; marked by <-- HERE in m/%s/
904
905(F) The named property which you specified via C<\p> or C<\P> is not one
906known to Perl. Perhaps you misspelled the name? See
e1b711da 907L<perluniprops/Properties accessible through \p{} and \P{}>
29f52644
KW
908for a complete list of available official
909properties. If it is a
910L<user-defined property|perlunicode/User-Defined Character Properties>
911it must have been defined by the time the regular expression is
912matched.
913
914If you didn't mean to use a Unicode property, escape the C<\p>, either
915by C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 916until C<\E>).
660a4616 917
b3647a36 918=item Can't fork: %s
a0d0e21e 919
be771a83
GS
920(F) A fatal error occurred while trying to fork while opening a
921pipeline.
a0d0e21e 922
b3647a36
SR
923=item Can't fork, trying again in 5 seconds
924
c973c02e 925(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
926after five seconds.
927
748a9306
LW
928=item Can't get filespec - stale stat buffer?
929
be771a83
GS
930(S) A warning peculiar to VMS. This arises because of the difference
931between access checks under VMS and under the Unix model Perl assumes.
932Under VMS, access checks are done by filename, rather than by bits in
933the stat buffer, so that ACLs and other protections can be taken into
934account. Unfortunately, Perl assumes that the stat buffer contains all
935the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 936the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
937the device name and FID present in the stat buffer, but this works only
938if you haven't made a subsequent call to the CRTL stat() routine,
939because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
940appears, the name lookup failed, and the access-checking routine gave up
941and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
942routine knows about the Perl C<stat> operator and file tests, so you
943shouldn't ever see this warning in response to a Perl command; it arises
944only if some internal code takes stat buffers lightly.)
748a9306 945
a0d0e21e
LW
946=item Can't get pipe mailbox device name
947
be771a83
GS
948(P) An error peculiar to VMS. After creating a mailbox to act as a
949pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
950
951=item Can't get SYSGEN parameter value for MAXBUF
952
748a9306
LW
953(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
954mailbox buffers to be, and didn't get an answer.
a0d0e21e 955
6df41af2 956=item Can't "goto" into the middle of a foreach loop
a0d0e21e 957
be771a83
GS
958(F) A "goto" statement was executed to jump into the middle of a foreach
959loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
960
961=item Can't "goto" out of a pseudo block
962
be771a83
GS
963(F) A "goto" statement was executed to jump out of what might look like
964a block, except that it isn't a proper block. This usually occurs if
965you tried to jump out of a sort() block or subroutine, which is a no-no.
966See L<perlfunc/goto>.
a0d0e21e 967
5a25739d
FC
968=item Can't goto subroutine from an eval-%s
969
970(F) The "goto subroutine" call can't be used to jump out of an eval
971"string" or block.
972
9850bf21 973=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 974
9850bf21
RH
975(F) The "goto subroutine" call can't be used to jump out of the
976comparison sub for a sort(), or from a similar callback (such
977as the reduce() function in List::Util).
978
6df41af2
GS
979=item Can't goto subroutine outside a subroutine
980
be771a83
GS
981(F) The deeply magical "goto subroutine" call can only replace one
982subroutine call for another. It can't manufacture one out of whole
983cloth. In general you should be calling it out of only an AUTOLOAD
984routine anyway. See L<perlfunc/goto>.
6df41af2 985
0b5b802d
GS
986=item Can't ignore signal CHLD, forcing to default
987
be771a83
GS
988(W signal) Perl has detected that it is being run with the SIGCHLD
989signal (sometimes known as SIGCLD) disabled. Since disabling this
990signal will interfere with proper determination of exit status of child
991processes, Perl has reset the signal to its default value. This
992situation typically indicates that the parent program under which Perl
993may be running (e.g. cron) is being very careless.
0b5b802d 994
e2c0f81f
DG
995=item Can't kill a non-numeric process ID
996
997(F) Process identifiers must be (signed) integers. It is a fatal error to
998attempt to kill() an undefined, empty-string or otherwise non-numeric
999process identifier.
1000
6df41af2 1001=item Can't "last" outside a loop block
4633a7c4 1002
6df41af2 1003(F) A "last" statement was executed to break out of the current block,
be771a83
GS
1004except that there's this itty bitty problem called there isn't a current
1005block. Note that an "if" or "else" block doesn't count as a "loopish"
1006block, as doesn't a block given to sort(), map() or grep(). You can
1007usually double the curlies to get the same effect though, because the
1008inner curlies will be considered a block that loops once. See
1009L<perlfunc/last>.
4633a7c4 1010
2c7d6b9c
RGS
1011=item Can't linearize anonymous symbol table
1012
1013(F) Perl tried to calculate the method resolution order (MRO) of a
1014package, but failed because the package stash has no name.
1015
b8170e59
JB
1016=item Can't load '%s' for module %s
1017
6903afa2
FC
1018(F) The module you tried to load failed to load a dynamic extension.
1019This may either mean that you upgraded your version of perl to one
1020that is incompatible with your old dynamic extensions (which is known
1021to happen between major versions of perl), or (more likely) that your
1022dynamic extension was built against an older version of the library
1023that is installed on your system. You may need to rebuild your old
1024dynamic extensions.
b8170e59 1025
748a9306
LW
1026=item Can't localize lexical variable %s
1027
2ba9eb46 1028(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
1029lexical variable using "my" or "state". This is not allowed. If you
1030want to localize a package variable of the same name, qualify it with
1031the package name.
748a9306 1032
6df41af2 1033=item Can't localize through a reference
4727527e 1034
6df41af2
GS
1035(F) You said something like C<local $$ref>, which Perl can't currently
1036handle, because when it goes to restore the old value of whatever $ref
be771a83 1037pointed to after the scope of the local() is finished, it can't be sure
64977eb6 1038that $ref will still be a reference.
4727527e 1039
ea071790 1040=item Can't locate %s
ec889f3a 1041
fa816bf3
FC
1042(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
1043Perl looks for the file in all the locations mentioned in @INC, unless
1044the file name included the full path to the file. Perhaps you need
1045to set the PERL5LIB or PERL5OPT environment variable to say where the
1046extra library is, or maybe the script needs to add the library name
be771a83
GS
1047to @INC. Or maybe you just misspelled the name of the file. See
1048L<perlfunc/require> and L<lib>.
a0d0e21e 1049
6df41af2
GS
1050=item Can't locate auto/%s.al in @INC
1051
be771a83
GS
1052(F) A function (or method) was called in a package which allows
1053autoload, but there is no function to autoload. Most probable causes
1054are a misprint in a function/method name or a failure to C<AutoSplit>
1055the file, say, by doing C<make install>.
6df41af2 1056
b8170e59
JB
1057=item Can't locate loadable object for module %s in @INC
1058
1059(F) The module you loaded is trying to load an external library, like
d70d8e57 1060for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1061unable to locate this library. See L<DynaLoader>.
1062
a0d0e21e
LW
1063=item Can't locate object method "%s" via package "%s"
1064
1065(F) You called a method correctly, and it correctly indicated a package
1066functioning as a class, but that package doesn't define that particular
2ba9eb46 1067method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1068
8af56b9d
FC
1069=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1070to load "%s"?)
1071
1072(F) You called a method on a class that did not exist, and the method
1073could not be found in UNIVERSAL. This often means that a method
1074requires a package that has not been loaded.
1075
a0d0e21e
LW
1076=item Can't locate package %s for @%s::ISA
1077
be771a83
GS
1078(W syntax) The @ISA array contained the name of another package that
1079doesn't seem to exist.
a0d0e21e 1080
2f7da168
RK
1081=item Can't locate PerlIO%s
1082
1083(F) You tried to use in open() a PerlIO layer that does not exist,
1084e.g. open(FH, ">:nosuchlayer", "somefile").
1085
f4ad53f4 1086=item Can't make list assignment to %ENV on this system
3e3baf6d 1087
be771a83
GS
1088(F) List assignment to %ENV is not supported on some systems, notably
1089VMS.
3e3baf6d 1090
cd40cd58
NC
1091=item Can't make loaded symbols global on this platform while loading %s
1092
ff9c1ae8 1093(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1094that symbols from the stated file are made available globally within the
1095process, but that functionality is not available on this platform. Whilst
1096the module likely will still work, this may prevent the perl interpreter
1097from loading other XS-based extensions which need to link directly to
1098functions defined in the C or XS code in the stated file.
1099
a0d0e21e
LW
1100=item Can't modify %s in %s
1101
be771a83
GS
1102(F) You aren't allowed to assign to the item indicated, or otherwise try
1103to change it, such as with an auto-increment.
a0d0e21e 1104
54310121 1105=item Can't modify nonexistent substring
a0d0e21e
LW
1106
1107(P) The internal routine that does assignment to a substr() was handed
1108a NULL.
1109
0f948285 1110=item Can't modify non-lvalue subroutine call of &%s
6df41af2
GS
1111
1112(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1113such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1114
cf6e1fa1
FC
1115=item Can't modify reference to %s in %s assignment
1116
1117(F) Only a limited number of constructs can be used as the argument to a
1118reference constructor on the left-hand side of an assignment, and what
1119you used was not one of them. See L<perlref/Assigning to References>.
1120
1121=item Can't modify reference to localized parenthesized array in list
1122assignment
1123
1124(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1125it is not clear exactly what it should do. If you meant to make @array
1126refer to some other array, use C<\@array = \@other_array>. If you want to
1127make the elements of @array aliases of the scalars referenced on the
1128right-hand side, use C<\(@array) = @scalar_refs>.
1129
1130=item Can't modify reference to parenthesized hash in list assignment
1131
1132(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1133refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1134make the elements of %hash into aliases of the scalars referenced on the
1135right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1136
5f05dabc 1137=item Can't msgrcv to read-only var
a0d0e21e 1138
5f05dabc 1139(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1140buffer.
1141
6df41af2
GS
1142=item Can't "next" outside a loop block
1143
1144(F) A "next" statement was executed to reiterate the current block, but
1145there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1146count as a "loopish" block, as doesn't a block given to sort(), map() or
1147grep(). You can usually double the curlies to get the same effect
1148though, because the inner curlies will be considered a block that loops
1149once. See L<perlfunc/next>.
6df41af2 1150
a0d0e21e
LW
1151=item Can't open %s: %s
1152
c47ff5f1 1153(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1154filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1155switches, or explicitly, failed for the indicated reason. Usually
1156this is because you don't have read permission for a file which
1157you named on the command line.
1158
1159(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1160your operating system's equivalent) could not be opened.
a0d0e21e 1161
9a869a14
RGS
1162=item Can't open a reference
1163
1164(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1165using the 3-arg open() syntax:
9a869a14
RGS
1166
1167 open FH, '>', $ref;
1168
1169but your version of perl is compiled without perlio, and this form of
1170open is not supported.
1171
a0d0e21e
LW
1172=item Can't open bidirectional pipe
1173
be771a83
GS
1174(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1175You can try any of several modules in the Perl library to do this, such
1176as IPC::Open2. Alternately, direct the pipe's output to a file using
1177">", and then read it in under a different file handle.
a0d0e21e 1178
748a9306
LW
1179=item Can't open error file %s as stderr
1180
be771a83
GS
1181(F) An error peculiar to VMS. Perl does its own command line
1182redirection, and couldn't open the file specified after '2>' or '2>>' on
1183the command line for writing.
748a9306
LW
1184
1185=item Can't open input file %s as stdin
1186
be771a83
GS
1187(F) An error peculiar to VMS. Perl does its own command line
1188redirection, and couldn't open the file specified after '<' on the
1189command line for reading.
748a9306
LW
1190
1191=item Can't open output file %s as stdout
1192
be771a83
GS
1193(F) An error peculiar to VMS. Perl does its own command line
1194redirection, and couldn't open the file specified after '>' or '>>' on
1195the command line for writing.
748a9306
LW
1196
1197=item Can't open output pipe (name: %s)
1198
be771a83
GS
1199(P) An error peculiar to VMS. Perl does its own command line
1200redirection, and couldn't open the pipe into which to send data destined
1201for stdout.
748a9306 1202
3b1cf97d 1203=item Can't open perl script "%s": %s
a0d0e21e
LW
1204
1205(F) The script you specified can't be opened for the indicated reason.
1206
fa3aa65a
JC
1207If you're debugging a script that uses #!, and normally relies on the
1208shell's $PATH search, the -S option causes perl to do that search, so
1209you don't have to type the path or C<`which $scriptname`>.
1210
6df41af2
GS
1211=item Can't read CRTL environ
1212
1213(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1214from the CRTL's internal environment array and discovered the array was
1215missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1216or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1217searched.
6df41af2 1218
f3106bc8
LM
1219=item Can't redeclare "%s" in "%s"
1220
1221(F) A "my", "our" or "state" declaration was found within another declaration,
1222such as C<my ($x, my($y), $z)> or C<our (my $x)>.
1223
6df41af2
GS
1224=item Can't "redo" outside a loop block
1225
1226(F) A "redo" statement was executed to restart the current block, but
1227there isn't a current block. Note that an "if" or "else" block doesn't
1228count as a "loopish" block, as doesn't a block given to sort(), map()
1229or grep(). You can usually double the curlies to get the same effect
1230though, because the inner curlies will be considered a block that
1231loops once. See L<perlfunc/redo>.
1232
64977eb6 1233=item Can't remove %s: %s, skipping file
10f9c03d 1234
be771a83
GS
1235(S inplace) You requested an inplace edit without creating a backup
1236file. Perl was unable to remove the original file to replace it with
1237the modified file. The file was left unmodified.
10f9c03d 1238
a0d0e21e
LW
1239=item Can't rename %s to %s: %s, skipping file
1240
e476b1b5 1241(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1242probably because you don't have write permission to the directory.
a0d0e21e 1243
748a9306
LW
1244=item Can't reopen input pipe (name: %s) in binary mode
1245
be771a83
GS
1246(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1247to reopen it to accept binary data. Alas, it failed.
748a9306 1248
9415f659
KW
1249=item Can't represent character for Ox%X on this platform
1250
1251(F) There is a hard limit to how big a character code point can be due
1252to the fundamental properties of UTF-8, especially on EBCDIC
1253platforms. The given code point exceeds that. The only work-around is
1254to not use such a large code point.
1255
4f12ec0e
FC
1256=item Can't reset %ENV on this system
1257
1258(F) You called C<reset('E')> or similar, which tried to reset
1259all variables in the current package beginning with "E". In
1260the main package, that includes %ENV. Resetting %ENV is not
1261supported on some systems, notably VMS.
1262
fe13d51d 1263=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1264
1fa582fa
FC
1265(F)(P) Error resolving overloading specified by a method name (as
1266opposed to a subroutine reference): no such method callable via the
1267package. If the method name is C<???>, this is an internal error.
6df41af2 1268
cd06dffe
GS
1269=item Can't return %s from lvalue subroutine
1270
be771a83
GS
1271(F) Perl detected an attempt to return illegal lvalues (such as
1272temporary or readonly values) from a subroutine used as an lvalue. This
1273is not allowed.
cd06dffe 1274
96ebfdd7
RK
1275=item Can't return outside a subroutine
1276
1277(F) The return statement was executed in mainline code, that is, where
1278there was no subroutine call to return out of. See L<perlsub>.
1279
78f9721b
SM
1280=item Can't return %s to lvalue scalar context
1281
6903afa2
FC
1282(F) You tried to return a complete array or hash from an lvalue
1283subroutine, but you called the subroutine in a way that made Perl
1284think you meant to return only one value. You probably meant to
1285write parentheses around the call to the subroutine, which tell
1286Perl that the call should be in list context.
78f9721b 1287
a0d0e21e
LW
1288=item Can't stat script "%s"
1289
be771a83
GS
1290(P) For some reason you can't fstat() the script even though you have it
1291open already. Bizarre.
a0d0e21e 1292
a0d0e21e
LW
1293=item Can't take log of %g
1294
fb73857a 1295(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1296negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1297standard with Perl, though, if you really want to do that for the
1298negative numbers.
a0d0e21e
LW
1299
1300=item Can't take sqrt of %g
1301
1302(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1303negative number. There's a Math::Complex package that comes standard
1304with Perl, though, if you really want to do that.
a0d0e21e
LW
1305
1306=item Can't undef active subroutine
1307
1308(F) You can't undefine a routine that's currently running. You can,
1309however, redefine it while it's running, and you can even undef the
1310redefined subroutine while the old routine is running. Go figure.
1311
c81225bc 1312=item Can't upgrade %s (%d) to %d
a0d0e21e 1313
be771a83
GS
1314(P) The internal sv_upgrade routine adds "members" to an SV, making it
1315into a more specialized kind of SV. The top several SV types are so
1316specialized, however, that they cannot be interconverted. This message
1317indicates that such a conversion was attempted.
a0d0e21e 1318
6651ba0b
FC
1319=item Can't use '%c' after -mname
1320
1321(F) You tried to call perl with the B<-m> switch, but you put something
1322other than "=" after the module name.
1323
1f1ec7b5
KW
1324=item Can't use a hash as a reference
1325
1326(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1327C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1328<= 5.22.0 used to allow this syntax, but shouldn't
1329have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1330
1331=item Can't use an array as a reference
1332
1333(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1334C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1335used to allow this syntax, but shouldn't have. This
1336was deprecated in perl 5.6.1.
1f1ec7b5 1337
1db89ea5
BS
1338=item Can't use anonymous symbol table for method lookup
1339
e27ad1f2 1340(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1341table that doesn't have a name. Symbol tables can become anonymous
1342for example by undefining stashes: C<undef %Some::Package::>.
1343
96ebfdd7
RK
1344=item Can't use an undefined value as %s reference
1345
1346(F) A value used as either a hard reference or a symbolic reference must
1347be a defined value. This helps to delurk some insidious errors.
1348
6df41af2
GS
1349=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1350
be771a83
GS
1351(F) Only hard references are allowed by "strict refs". Symbolic
1352references are disallowed. See L<perlref>.
6df41af2 1353
90b75b61 1354=item Can't use %! because Errno.pm is not available
1d2dff63 1355
20561843 1356(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1357Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1358provide symbolic names for C<$!> errno values.
1359
1109a392
MHM
1360=item Can't use both '<' and '>' after type '%c' in %s
1361
1362(F) A type cannot be forced to have both big-endian and little-endian
1363byte-order at the same time, so this combination of modifiers is not
1364allowed. See L<perlfunc/pack>.
1365
e35475de
KW
1366=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1367
1368(F) defined() is not useful on arrays because it
1369checks for an undefined I<scalar> value. If you want to see if the
1370array is empty, just use C<if (@array) { # not empty }> for example.
1371
1372=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1373
1374(F) C<defined()> is not usually right on hashes.
1375
1376Although C<defined %hash> is false on a plain not-yet-used hash, it
1377becomes true in several non-obvious circumstances, including iterators,
1378weak references, stash names, even remaining true after C<undef %hash>.
1379These things make C<defined %hash> fairly useless in practice, so it now
1380generates a fatal error.
1381
1382If a check for non-empty is what you wanted then just put it in boolean
1383context (see L<perldata/Scalar values>):
1384
1385 if (%hash) {
1386 # not empty
1387 }
1388
1389If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1390variable exists then that's never really been reliable, and isn't
1391a good way to enquire about the features of a package, or whether
1392it's loaded, etc.
1393
6df41af2
GS
1394=item Can't use %s for loop variable
1395
c1f06047 1396(P) The parser got confused when trying to parse a C<foreach> loop.
6df41af2 1397
aab6a793 1398=item Can't use global %s in "%s"
6df41af2 1399
be771a83
GS
1400(F) You tried to declare a magical variable as a lexical variable. This
1401is not allowed, because the magic can be tied to only one location
1402(namely the global variable) and it would be incredibly confusing to
1403have variables in your program that looked like magical variables but
6df41af2
GS
1404weren't.
1405
6d3b25aa
RGS
1406=item Can't use '%c' in a group with different byte-order in %s
1407
1408(F) You attempted to force a different byte-order on a type
1409that is already inside a group with a byte-order modifier.
1410For example you cannot force little-endianness on a type that
1411is inside a big-endian group.
1412
c07a80fd
PP
1413=item Can't use "my %s" in sort comparison
1414
1415(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1416You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1417and the variable had earlier been declared as a lexical variable.
1418Either qualify the sort variable with the package name, or rename the
1419lexical variable.
1420
a0d0e21e
LW
1421=item Can't use %s ref as %s ref
1422
1423(F) You've mixed up your reference types. You have to dereference a
1424reference of the type needed. You can use the ref() function to
1425test the type of the reference, if need be.
1426
748a9306 1427=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1428
5e634d20
FC
1429=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1430
b41bf23f
FC
1431(F) You've told Perl to dereference a string, something which
1432C<use strict> blocks to prevent it happening accidentally. See
1433L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1434in a double-quoted string immediately before interpolating a variable,
1435for example in C<"user @$twitter_id">, which says to treat the contents
1436of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1437symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1438
748a9306
LW
1439=item Can't use subscript on %s
1440
1441(F) The compiler tried to interpret a bracketed expression as a
1442subscript. But to the left of the brackets was an expression that
209e7cf1 1443didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1444
6df41af2
GS
1445=item Can't use \%c to mean $%c in expression
1446
75b44862
GS
1447(W syntax) In an ordinary expression, backslash is a unary operator that
1448creates a reference to its argument. The use of backslash to indicate a
1449backreference to a matched substring is valid only as part of a regular
be771a83
GS
1450expression pattern. Trying to do this in ordinary Perl code produces a
1451value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1452instead.
6df41af2 1453
810b8aa5
GS
1454=item Can't weaken a nonreference
1455
1456(F) You attempted to weaken something that was not a reference. Only
1457references can be weakened.
1458
fc7debfb
FC
1459=item Can't "when" outside a topicalizer
1460
1461(F) You have used a when() block that is neither inside a C<foreach>
1462loop nor a C<given> block. (Note that this error is issued on exit
1463from the C<when> block, so you won't get the error if the match fails,
1464or if you use an explicit C<continue>.)
1465
5f05dabc 1466=item Can't x= to read-only value
a0d0e21e 1467
be771a83
GS
1468(F) You tried to repeat a constant value (often the undefined value)
1469with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1470Perhaps you need to copy the value to a temporary, and repeat that.
1471
a04e6aad 1472=item Character following "\c" must be printable ASCII
f9d13529 1473
7357bd17 1474(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1475
727b6379 1476Note that ASCII characters that don't map to control characters are
7357bd17 1477discouraged, and will generate the warning (when enabled)
727b6379 1478L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1479
163a633c
KW
1480=item Character following \%c must be '{' or a single-character Unicode property name in regex; marked by <-- HERE in m/%s/
1481
1482(F) (In the above the C<%c> is replaced by either C<p> or C<P>.) You
1483specified something that isn't a legal Unicode property name. Most
1484Unicode properties are specified by C<\p{...}>. But if the name is a
1485single character one, the braces may be omitted.
1486
f337b084 1487=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1488
1489(W pack) You said
1490
1491 pack("C", $x)
1492
1493where $x is either less than 0 or more than 255; the C<"C"> format is
1494only for encoding native operating system characters (ASCII, EBCDIC,
1495and so on) and not for Unicode characters, so Perl behaved as if you meant
1496
1497 pack("C", $x & 255)
1498
1499If you actually want to pack Unicode codepoints, use the C<"U"> format
1500instead.
1501
f337b084 1502=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1503
1504(W pack) You said
1505
1506 pack("c", $x)
1507
1508where $x is either less than -128 or more than 127; the C<"c"> format
1509is only for encoding native operating system characters (ASCII, EBCDIC,
1510and so on) and not for Unicode characters, so Perl behaved as if you meant
1511
1512 pack("c", $x & 255);
1513
1514If you actually want to pack Unicode codepoints, use the C<"U"> format
1515instead.
1516
f337b084
TH
1517=item Character in '%c' format wrapped in unpack
1518
1519(W unpack) You tried something like
1520
1521 unpack("H", "\x{2a1}")
1522
1a147d38 1523where the format expects to process a byte (a character with a value
6903afa2
FC
1524below 256), but a higher value was provided instead. Perl uses the
1525value modulus 256 instead, as if you had provided:
f337b084
TH
1526
1527 unpack("H", "\x{a1}")
1528
5a25739d
FC
1529=item Character in 'W' format wrapped in pack
1530
1531(W pack) You said
1532
1533 pack("U0W", $x)
1534
1535where $x is either less than 0 or more than 255. However, C<U0>-mode
1536expects all values to fall in the interval [0, 255], so Perl behaved
1537as if you meant:
1538
1539 pack("U0W", $x & 255)
1540
f337b084
TH
1541=item Character(s) in '%c' format wrapped in pack
1542
1543(W pack) You tried something like
1544
1545 pack("u", "\x{1f3}b")
1546
1a147d38 1547where the format expects to process a sequence of bytes (character with a
6903afa2 1548value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1549uses the character values modulus 256 instead, as if you had provided:
1550
1551 pack("u", "\x{f3}b")
1552
1553=item Character(s) in '%c' format wrapped in unpack
1554
1555(W unpack) You tried something like
1556
1557 unpack("s", "\x{1f3}b")
1558
1a147d38 1559where the format expects to process a sequence of bytes (character with a
6903afa2 1560value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1561uses the character values modulus 256 instead, as if you had provided:
1562
1563 unpack("s", "\x{f3}b")
1564
f51551f7
FC
1565=item charnames alias definitions may not contain a sequence of multiple spaces
1566
1567(F) You defined a character name which had multiple space characters
1568in a row. Change them to single spaces. Usually these names are
1569defined in the C<:alias> import argument to C<use charnames>, but they
1570could be defined by a translator installed into C<$^H{charnames}>. See
1571L<charnames/CUSTOM ALIASES>.
1572
1573=item charnames alias definitions may not contain trailing white-space
1574
1575(F) You defined a character name which ended in a space
1576character. Remove the trailing space(s). Usually these names are
1577defined in the C<:alias> import argument to C<use charnames>, but they
1578could be defined by a translator installed into C<$^H{charnames}>.
1579See L<charnames/CUSTOM ALIASES>.
1580
60121127
TC
1581=item chdir() on unopened filehandle %s
1582
1583(W unopened) You tried chdir() on a filehandle that was never opened.
1584
33c28ab2
DM
1585=item \C no longer supported in regex; marked by S<<-- HERE> in m/%s/
1586
1587(F) The \C character class used to allow a match of single byte within a
1588multi-byte utf-8 character, but was removed in v5.24 as it broke
1589encapsulation and its implementation was extremely buggy. If you really
1590need to process the individual bytes, you probably want to convert your
1591string to one where each underlying byte is stored as a character, with
1592utf8::encode().
f51551f7 1593
f866a7cd
FC
1594=item "\c%c" is more clearly written simply as "%s"
1595
1596(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1597non-printable characters. You used it for a printable one, which
1598is better written as simply itself, perhaps preceded by a backslash
1599for non-word characters. Doing it the way you did is not portable
1600between ASCII and EBCDIC platforms.
f866a7cd 1601
6651ba0b
FC
1602=item Cloning substitution context is unimplemented
1603
1604(F) Creating a new thread inside the C<s///> operator is not supported.
1605
abc7ecad
SP
1606=item closedir() attempted on invalid dirhandle %s
1607
1608(W io) The dirhandle you tried to close is either closed or not really
1609a dirhandle. Check your control flow.
1610
5a25739d
FC
1611=item close() on unopened filehandle %s
1612
1613(W unopened) You tried to close a filehandle that was never opened.
1614
541ed3a9
FC
1615=item Closure prototype called
1616
1617(F) If a closure has attributes, the subroutine passed to an attribute
1618handler is the prototype that is cloned when a new closure is created.
1619This subroutine cannot be called.
1620
49704364
LW
1621=item Code missing after '/'
1622
6903afa2
FC
1623(F) You had a (sub-)template that ends with a '/'. There must be
1624another template code following the slash. See L<perlfunc/pack>.
49704364 1625
c0236afe
KW
1626=item Code point 0x%X is not Unicode, and not portable
1627
1628(S non_unicode) You had a code point that has never been in any
1629standard, so it is likely that languages other than Perl will NOT
1630understand it. At one time, it was legal in some standards to have code
1631points up to 0x7FFF_FFFF, but not higher, and this code point is higher.
1632
1633Acceptance of these code points is a Perl extension, and you should
1634expect that nothing other than Perl can handle them; Perl itself on
1635EBCDIC platforms before v5.24 does not handle them.
1636
1637Code points above 0xFFFF_FFFF require larger than a 32 bit word.
1638
1639Perl also makes no guarantees that the representation of these code
1640points won't change at some point in the future, say when machines
1641become available that have larger than a 64-bit word. At that time,
1642files written by an older Perl would require conversion before being
1643readable by a newer Perl.
1644
5a25739d
FC
1645=item Code point 0x%X is not Unicode, may not be portable
1646
2d88a86a 1647(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1648of U+10FFFF.
1649
c0236afe
KW
1650Perl allows strings to contain a superset of Unicode code points, but
1651these may not be accepted by other languages/systems. Further, even if
1652these languages/systems accept these large code points, they may have
1653chosen a different representation for them than the UTF-8-like one that
1654Perl has, which would mean files are not exchangeable between them and
1655Perl.
1656
1657On EBCDIC platforms, code points above 0x3FFF_FFFF have a different
1658representation in Perl v5.24 than before, so any file containing these
1659that was written before that version will require conversion before
1660being readable by a later Perl.
0876b9a0 1661
6df41af2
GS
1662=item %s: Command not found
1663
a892b81a 1664(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1665instead of Perl. Check the #! line, or manually feed your script into
1666Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1667
1668 #!/usr/bin/perl -w
6df41af2 1669
7a2e2cd6
PP
1670=item Compilation failed in require
1671
1672(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1673Perl uses this generic message when none of the errors that it
1674encountered were severe enough to halt compilation immediately.
7a2e2cd6 1675
c3464db5
DD
1676=item Complex regular subexpression recursion limit (%d) exceeded
1677
be771a83
GS
1678(W regexp) The regular expression engine uses recursion in complex
1679situations where back-tracking is required. Recursion depth is limited
1680to 32766, or perhaps less in architectures where the stack cannot grow
1681arbitrarily. ("Simple" and "medium" situations are handled without
1682recursion and are not subject to a limit.) Try shortening the string
1683under examination; looping in Perl code (e.g. with C<while>) rather than
1684in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1685that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1686on I<Mastering Regular Expressions>.)
c3464db5 1687
69282e91 1688=item connect() on closed socket %s
a0d0e21e 1689
be771a83
GS
1690(W closed) You tried to do a connect on a closed socket. Did you forget
1691to check the return value of your socket() call? See
1692L<perlfunc/connect>.
a0d0e21e 1693
e21e7c6a
FC
1694=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1695
1696(F) The subroutine registered to handle constant overloading
1697(see L<overload>) or a custom charnames handler (see
1698L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1699
1700=item Constant(%s): $^H{%s} is not defined
1701
1702(F) The parser found inconsistencies while attempting to define an
1703overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1704L<overload> pragma?
e21e7c6a 1705
779c5bc9
GS
1706=item Constant is not %s reference
1707
1708(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1709is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1710The message indicates the type of reference that was expected. This
be771a83 1711usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1712See L<perlsub/"Constant Functions"> and L<constant>.
1713
0ac016fc
FC
1714=item Constants from lexical variables potentially modified elsewhere are
1715deprecated
1716
1717(D deprecated) You wrote something like
1718
1719 my $var;
1720 $sub = sub () { $var };
1721
1722but $var is referenced elsewhere and could be modified after the C<sub>
1723expression is evaluated. Either it is explicitly modified elsewhere
1724(C<$var = 3>) or it is passed to a subroutine or to an operator like
1725C<printf> or C<map>, which may or may not modify the variable.
1726
1727Traditionally, Perl has captured the value of the variable at that
1728point and turned the subroutine into a constant eligible for inlining.
1729In those cases where the variable can be modified elsewhere, this
1730breaks the behavior of closures, in which the subroutine captures
1731the variable itself, rather than its value, so future changes to the
1732variable are reflected in the subroutine's return value.
1733
1734This usage is deprecated, because the behavior is likely to change
1735in a future version of Perl.
1736
1737If you intended for the subroutine to be eligible for inlining, then
1738make sure the variable is not referenced elsewhere, possibly by
1739copying it:
1740
1741 my $var2 = $var;
1742 $sub = sub () { $var2 };
1743
1744If you do want this subroutine to be a closure that reflects future
1745changes to the variable that it closes over, add an explicit C<return>:
1746
1747 my $var;
1748 $sub = sub () { return $var };
1749
4cee8e80
CS
1750=item Constant subroutine %s redefined
1751
aeb94125
FC
1752(W redefine)(S) You redefined a subroutine which had previously
1753been eligible for inlining. See L<perlsub/"Constant Functions">
1754for commentary and workarounds.
4cee8e80 1755
9607fc9c
PP
1756=item Constant subroutine %s undefined
1757
be771a83
GS
1758(W misc) You undefined a subroutine which had previously been eligible
1759for inlining. See L<perlsub/"Constant Functions"> for commentary and
1760workarounds.
9607fc9c 1761
5a25739d
FC
1762=item Constant(%s) unknown
1763
1764(F) The parser found inconsistencies either while attempting
1765to define an overloaded constant, or when trying to find the
1766character name specified in the C<\N{...}> escape. Perhaps you
3ee1a09c 1767forgot to load the corresponding L<overload> pragma?
5a25739d 1768
4a873d7a
FC
1769=item :const is experimental
1770
1771(S experimental::const_attr) The "const" attribute is experimental.
1772If you want to use the feature, disable the warning with C<no warnings
1773'experimental::const_attr'>, but know that in doing so you are taking
1774the risk that your code may break in a future Perl version.
1775
b77472f9
FC
1776=item :const is not permitted on named subroutines
1777
1778(F) The "const" attribute causes an anonymous subroutine to be run and
465068b9 1779its value captured at the time that it is cloned. Named subroutines are
b77472f9
FC
1780not cloned like this, so the attribute does not make sense on them.
1781
e7ea3e70
IZ
1782=item Copy method did not return a reference
1783
6903afa2 1784(F) The method which overloads "=" is buggy. See
13a2d996 1785L<overload/Copy Constructor>.
e7ea3e70 1786
4aaa4757
FC
1787=item &CORE::%s cannot be called directly
1788
1789(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1790with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1791in this package cannot yet be called that way, but must be
1792called as barewords. Something like this will work:
1793
1794 BEGIN { *shove = \&CORE::push; }
1795 shove @array, 1,2,3; # pushes on to @array
1796
6798c92b
GS
1797=item CORE::%s is not a keyword
1798
1799(F) The CORE:: namespace is reserved for Perl keywords.
1800
675fa9ff
FC
1801=item Corrupted regexp opcode %d > %d
1802
1803(P) This is either an error in Perl, or, if you're using
1804one, your L<custom regular expression engine|perlreapi>. If not the
1805latter, report the problem through the L<perlbug> utility.
1806
a0d0e21e
LW
1807=item corrupted regexp pointers
1808
1809(P) The regular expression engine got confused by what the regular
1810expression compiler gave it.
1811
1812=item corrupted regexp program
1813
be771a83
GS
1814(P) The regular expression engine got passed a regexp program without a
1815valid magic number.
a0d0e21e 1816
de42a5a9 1817=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1818
1819(P) The malloc package that comes with Perl had an internal failure.
1820
49704364
LW
1821=item Count after length/code in unpack
1822
1823(F) You had an unpack template indicating a counted-length string, but
1824you have also specified an explicit size for the string. See
1825L<perlfunc/pack>.
1826
f2cccb4c
KW
1827=for comment
1828The following are used in lib/diagnostics.t for testing two =items that
1829share the same description. Changes here need to be propagated to there
1830
6651ba0b
FC
1831=item Deep recursion on anonymous subroutine
1832
a0d0e21e
LW
1833=item Deep recursion on subroutine "%s"
1834
be771a83
GS
1835(W recursion) This subroutine has called itself (directly or indirectly)
1836100 times more than it has returned. This probably indicates an
1837infinite recursion, unless you're writing strange benchmark programs, in
1838which case it indicates something else.
a0d0e21e 1839
aad1d01f
NC
1840This threshold can be changed from 100, by recompiling the F<perl> binary,
1841setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1842
e0e4a6e3
FC
1843=item (?(DEFINE)....) does not allow branches in regex; marked by
1844S<<-- HERE> in m/%s/
bcb95744 1845
6903afa2 1846(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1847most likely cause of this error is that you left out a parenthesis inside
1848of the C<....> part.
1849
6e8a73f2 1850The S<<-- HERE> shows whereabouts in the regular expression the problem was
bcb95744
FC
1851discovered.
1852
62658f4d
PM
1853=item %s defines neither package nor VERSION--version check failed
1854
1855(F) You said something like "use Module 42" but in the Module file
1856there are neither package declarations nor a C<$VERSION>.
1857
36447869
FC
1858=item delete argument is index/value array slice, use array slice
1859
1860(F) You used index/value array slice syntax (C<%array[...]>) as
1861the argument to C<delete>. You probably meant C<@array[...]> with
1862an @ symbol instead.
1863
1864=item delete argument is key/value hash slice, use hash slice
1865
1866(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1867C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1868
0ffcbc25
FC
1869=item delete argument is not a HASH or ARRAY element or slice
1870
4a0af295 1871(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1872such as:
1873
1874 $foo{$bar}
1875 $ref->{"susie"}[12]
1876
1877or a hash or array slice, such as:
1878
1879 @foo[$bar, $baz, $xyzzy]
1880 @{$ref->[12]}{"susie", "queue"}
1881
fc36a67e
PP
1882=item Delimiter for here document is too long
1883
be771a83
GS
1884(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1885long for Perl to handle. You have to be seriously twisted to write code
1886that triggers this error.
fc36a67e 1887
6d3b25aa
RGS
1888=item Deprecated use of my() in false conditional
1889
fa816bf3
FC
1890(D deprecated) You used a declaration similar to C<my $x if 0>. There
1891has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1892not to be cleared at scope exit when its declaration includes a false
6903afa2 1893conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1894static variable. Since we intend to fix this bug, we don't want people
6903afa2 1895relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1896declaring the variable in a separate block outside the function, eg
36fb85f3 1897
6d3b25aa
RGS
1898 sub f { my $x if 0; return $x++ }
1899
1900becomes
1901
1902 { my $x; sub f { return $x++ } }
1903
ea9d9ebc 1904Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1905lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1906
1907 sub f { state $x; return $x++ }
1908
500ab966
RGS
1909=item DESTROY created new reference to dead object '%s'
1910
1911(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1912just being DESTROYed. Perl is confused, and prefers to abort rather
1913than to create a dangling reference.
500ab966 1914
3cdd684c
TP
1915=item Did not produce a valid header
1916
1917See Server error.
1918
6df41af2
GS
1919=item %s did not return a true value
1920
1921(F) A required (or used) file must return a true value to indicate that
1922it compiled correctly and ran its initialization code correctly. It's
1923traditional to end such a file with a "1;", though any true value would
1924do. See L<perlfunc/require>.
1925
cc507455 1926=item (Did you mean &%s instead?)
4633a7c4 1927
413ff9f6
FC
1928(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1929some such.
4633a7c4 1930
cc507455 1931=item (Did you mean "local" instead of "our"?)
33633739 1932
be771a83
GS
1933(W misc) Remember that "our" does not localize the declared global
1934variable. You have declared it again in the same lexical scope, which
1935seems superfluous.
33633739 1936
cc507455 1937=item (Did you mean $ or @ instead of %?)
a0d0e21e 1938
be771a83
GS
1939(W) You probably said %hash{$key} when you meant $hash{$key} or
1940@hash{@keys}. On the other hand, maybe you just meant %hash and got
1941carried away.
748a9306 1942
7e1af8bc 1943=item Died
5f05dabc
PP
1944
1945(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1946you called it with no args and C<$@> was empty.
5f05dabc 1947
3cdd684c
TP
1948=item Document contains no data
1949
1950See Server error.
1951
62658f4d
PM
1952=item %s does not define %s::VERSION--version check failed
1953
1954(F) You said something like "use Module 42" but the Module did not
943fc58e 1955define a C<$VERSION>.
62658f4d 1956
49704364
LW
1957=item '/' does not take a repeat count
1958
1959(F) You cannot put a repeat count of any kind right after the '/' code.
1960See L<perlfunc/pack>.
1961
95cb0d72
FC
1962=item Don't know how to get file name
1963
1964(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1965somehow called on another platform. This should not happen.
1966
4021c788 1967=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1968
1969(P) The internal handling of magical variables has been cursed.
1970
1971=item do_study: out of memory
1972
1973(P) This should have been caught by safemalloc() instead.
1974
6df41af2
GS
1975=item (Do you need to predeclare %s?)
1976
56da5a46
RGS
1977(S syntax) This is an educated guess made in conjunction with the message
1978"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1979name is being referenced that hasn't been declared yet. This may be
1980because of ordering problems in your file, or because of a missing
be771a83
GS
1981"sub", "package", "require", or "use" statement. If you're referencing
1982something that isn't defined yet, you don't actually have to define the
1983subroutine or package before the current location. You can use an empty
1984"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1985
ac206dc8
RGS
1986=item dump() better written as CORE::dump()
1987
1988(W misc) You used the obsolescent C<dump()> built-in function, without fully
1989qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1990
84d78eb7
YO
1991=item dump is not supported
1992
1993(F) Your machine doesn't support dump/undump.
1994
a0d0e21e
LW
1995=item Duplicate free() ignored
1996
be771a83
GS
1997(S malloc) An internal routine called free() on something that had
1998already been freed.
a0d0e21e 1999
1109a392
MHM
2000=item Duplicate modifier '%c' after '%c' in %s
2001
35f0cd76
FC
2002(W unpack) You have applied the same modifier more than once after a
2003type in a pack template. See L<perlfunc/pack>.
1109a392 2004
4633a7c4
LW
2005=item elseif should be elsif
2006
fa816bf3
FC
2007(S syntax) There is no keyword "elseif" in Perl because Larry thinks
2008it's ugly. Your code will be interpreted as an attempt to call a method
2009named "elseif" for the class returned by the following block. This is
4633a7c4
LW
2010unlikely to be what you want.
2011
e0e4a6e3 2012=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 2013
af6f566e 2014(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 2015described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 2016a regular expression without specifying the property name.
ab13f0c7 2017
85ab1d1d 2018=item entering effective %s failed
5ff3f7a4 2019
85ab1d1d 2020(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2021effective uids or gids failed.
2022
c038024b
RGS
2023=item %ENV is aliased to %s
2024
2025(F) You're running under taint mode, and the C<%ENV> variable has been
2026aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 2027program's environment. This is potentially insecure.
c038024b 2028
748a9306
LW
2029=item Error converting file specification %s
2030
5f05dabc 2031(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 2032specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
2033single form when it must operate on them directly. Either you've passed
2034an invalid file specification to Perl, or you've found a case the
2035conversion routines don't handle. Drat.
748a9306 2036
ad19ef22 2037=item Eval-group in insecure regular expression
e4d48cc9 2038
be771a83
GS
2039(F) Perl detected tainted data when trying to compile a regular
2040expression that contains the C<(?{ ... })> zero-width assertion, which
2041is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 2042
ad19ef22 2043=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 2044
be771a83
GS
2045(F) Perl tried to compile a regular expression containing the
2046C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
2047pattern contains interpolated values. Since that is a security risk,
2048it is not allowed. If you insist, you may still do this by using the
2049C<re 'eval'> pragma or by explicitly building the pattern from an
2050interpolated string at run time and using that in an eval(). See
2051L<perlre/(?{ code })>.
e4d48cc9 2052
ad19ef22 2053=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 2054
be771a83
GS
2055(F) A regular expression contained the C<(?{ ... })> zero-width
2056assertion, but that construct is only allowed when the C<use re 'eval'>
2057pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 2058
e0e4a6e3
FC
2059=item EVAL without pos change exceeded limit in regex; marked by
2060S<<-- HERE> in m/%s/
1a147d38
YO
2061
2062(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 2063any text. Restructure the pattern so that text is consumed.
1a147d38 2064
6e8a73f2 2065The S<<-- HERE> shows whereabouts in the regular expression the problem was
1a147d38
YO
2066discovered.
2067
fc36a67e
PP
2068=item Excessively long <> operator
2069
2070(F) The contents of a <> operator may not exceed the maximum size of a
2071Perl identifier. If you're just trying to glob a long list of
2072filenames, try using the glob() operator, or put the filenames into a
2073variable and glob that.
2074
ed9aa3b7
SG
2075=item exec? I'm not *that* kind of operating system
2076
af8bb25a 2077(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 2078OS. See L<perlport>.
ed9aa3b7 2079
fe13d51d 2080=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
2081
2082(F) The final summary message when a Perl compilation fails.
2083
0ffcbc25
FC
2084=item exists argument is not a HASH or ARRAY element or a subroutine
2085
4a0af295 2086(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
2087subroutine with an ampersand, such as:
2088
2089 $foo{$bar}
2090 $ref->{"susie"}[12]
2091 &do_something
2092
2093=item exists argument is not a subroutine name
2094
ccfc2567
FC
2095(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
2096and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 2097
a0d0e21e
LW
2098=item Exiting eval via %s
2099
be771a83
GS
2100(W exiting) You are exiting an eval by unconventional means, such as a
2101goto, or a loop control statement.
e476b1b5
GS
2102
2103=item Exiting format via %s
2104
9a2ff54b 2105(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2106goto, or a loop control statement.
a0d0e21e 2107
0a753a76
PP
2108=item Exiting pseudo-block via %s
2109
be771a83
GS
2110(W exiting) You are exiting a rather special block construct (like a
2111sort block or subroutine) by unconventional means, such as a goto, or a
2112loop control statement. See L<perlfunc/sort>.
0a753a76 2113
a0d0e21e
LW
2114=item Exiting subroutine via %s
2115
be771a83
GS
2116(W exiting) You are exiting a subroutine by unconventional means, such
2117as a goto, or a loop control statement.
a0d0e21e
LW
2118
2119=item Exiting substitution via %s
2120
be771a83
GS
2121(W exiting) You are exiting a substitution by unconventional means, such
2122as a return, a goto, or a loop control statement.
a0d0e21e 2123
e0e4a6e3 2124=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2125
675fa9ff 2126(F) You wrote something like
c608e803
KW
2127
2128 (?13
2129
2130to denote a capturing group of the form
2131L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2132but omitted the C<")">.
2133
e0e4a6e3 2134=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2135
8b6fbf55
FC
2136(F) The C<(?[...])> extended character class regular expression construct
2137only allows character classes (including character class escapes like
2138C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2139containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2140This allows a regular expression containing just C<(?[...])> to be
2141interpolated. If you see this error message, then you probably
2142have some other C<(?...)> construct inside your character class. See
2143L<perlrecharclass/Extended Bracketed Character Classes>.
2144
baabe3fb 2145=item Experimental aliasing via reference not enabled
1f8155a2 2146
baabe3fb 2147(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2148
baabe3fb
FC
2149 no warnings "experimental::refaliasing";
2150 use feature "refaliasing";
1f8155a2
FC
2151 \$x = \$y;
2152
30d9c59b
Z
2153=item Experimental subroutine signatures not enabled
2154
2155(F) To use subroutine signatures, you must first enable them:
2156
caa35032 2157 no warnings "experimental::signatures";
30d9c59b
Z
2158 use feature "signatures";
2159 sub foo ($left, $right) { ... }
2160
b9234255 2161=item Experimental %s on scalar is now forbidden
26230909 2162
b9234255
AC
2163(F) An experimental feature added in Perl 5.14 allowed C<each>, C<keys>,
2164C<push>, C<pop>, C<shift>, C<splice>, C<unshift>, and C<values> to be called
26230909
AC
2165with a scalar argument. This experiment is considered unsuccessful, and has
2166been removed. The C<postderef> feature may meet your needs better.
2167
6da34ecb
FC
2168=item Experimental "%s" subs not enabled
2169
2170(F) To use lexical subs, you must first enable them:
2171
2172 no warnings 'experimental::lexical_subs';
2173 use feature 'lexical_subs';
2174 my sub foo { ... }
2175
7b8d334a
GS
2176=item Explicit blessing to '' (assuming package main)
2177
be771a83
GS
2178(W misc) You are blessing a reference to a zero length string. This has
2179the effect of blessing the reference into the package main. This is
2180usually not what you want. Consider providing a default target package,
2181e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2182
6df41af2
GS
2183=item %s: Expression syntax
2184
be771a83
GS
2185(A) You've accidentally run your script through B<csh> instead of Perl.
2186Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2187
2188=item %s failed--call queue aborted
2189
3c10abe3
AG
2190(F) An untrapped exception was raised while executing a UNITCHECK,
2191CHECK, INIT, or END subroutine. Processing of the remainder of the
2192queue of such routines has been prematurely ended.
6df41af2 2193
e0e4a6e3 2194=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2195
98d31c73 2196(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2197character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2198in your false range is interpreted as a literal "-". In a C<(?[...])>
2199construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2200the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2201the problem was discovered. See L<perlre>.
73b437c8 2202
1b1ee2ef 2203=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2204
be771a83
GS
2205(P) An error peculiar to VMS. Something untoward happened in a VMS
2206system service or RTL routine; Perl's exit status should provide more
2207details. The filename in "at %s" and the line number in "line %d" tell
2208you which section of the Perl source code is distressed.
a0d0e21e
LW
2209
2210=item fcntl is not implemented
2211
2212(F) Your machine apparently doesn't implement fcntl(). What is this, a
2213PDP-11 or something?
2214
22846ab4
AB
2215=item FETCHSIZE returned a negative value
2216
2217(F) A tied array claimed to have a negative number of elements, which
2218is not possible.
2219
f337b084
TH
2220=item Field too wide in 'u' format in pack
2221
d8b5cc61 2222(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2223which can't encode values above 63. So there is no point in asking for
2224a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2225C<u63> as the format.
f337b084 2226
af8c498a 2227=item Filehandle %s opened only for input
a0d0e21e 2228
6c8d78fb
HS
2229(W io) You tried to write on a read-only filehandle. If you intended
2230it to be a read-write filehandle, you needed to open it with "+<" or
2231"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2232write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2233
af8c498a 2234=item Filehandle %s opened only for output
a0d0e21e 2235
6c8d78fb
HS
2236(W io) You tried to read from a filehandle opened only for writing, If
2237you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2238with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2239read from the file, use "<". See L<perlfunc/open>. Another possibility
2240is that you attempted to open filedescriptor 0 (also known as STDIN) for
2241output (maybe you closed STDIN earlier?).
97828cef
RGS
2242
2243=item Filehandle %s reopened as %s only for input
2244
2245(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2246as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2247previously.
2248
2249=item Filehandle STDIN reopened as %s only for output
2250
2251(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2252as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2253
2254=item Final $ should be \$ or $name
2255
2256(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2257a literal dollar sign, or was meant to introduce a variable name that
2258happens to be missing. So you have to put either the backslash or the
2259name.
a0d0e21e 2260
56e90b21
GS
2261=item flock() on closed filehandle %s
2262
be771a83 2263(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2264some time before now. Check your control flow. flock() operates on
be771a83
GS
2265filehandles. Are you attempting to call flock() on a dirhandle by the
2266same name?
56e90b21 2267
6df41af2
GS
2268=item Format not terminated
2269
2270(F) A format must be terminated by a line with a solitary dot. Perl got
2271to the end of your file without finding such a line.
2272
a0d0e21e
LW
2273=item Format %s redefined
2274
e476b1b5 2275(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2276
2277 {
271595cc 2278 no warnings 'redefine';
a0d0e21e
LW
2279 eval "format NAME =...";
2280 }
2281
a0d0e21e
LW
2282=item Found = in conditional, should be ==
2283
e476b1b5 2284(W syntax) You said
a0d0e21e
LW
2285
2286 if ($foo = 123)
2287
2288when you meant
2289
2290 if ($foo == 123)
2291
2292(or something like that).
2293
6df41af2
GS
2294=item %s found where operator expected
2295
56da5a46
RGS
2296(S syntax) The Perl lexer knows whether to expect a term or an operator.
2297If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2298operator, it gives you this warning. Usually it indicates that an
2299operator or delimiter was omitted, such as a semicolon.
6df41af2 2300
a0d0e21e
LW
2301=item gdbm store returned %d, errno %d, key "%s"
2302
2303(S) A warning from the GDBM_File extension that a store failed.
2304
2305=item gethostent not implemented
2306
2307(F) Your C library apparently doesn't implement gethostent(), probably
2308because if it did, it'd feel morally obligated to return every hostname
2309on the Internet.
2310
69282e91 2311=item get%sname() on closed socket %s
a0d0e21e 2312
be771a83
GS
2313(W closed) You tried to get a socket or peer socket name on a closed
2314socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2315
748a9306
LW
2316=item getpwnam returned invalid UIC %#o for user "%s"
2317
2318(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2319C<getpwnam> operator returned an invalid UIC.
2320
6df41af2
GS
2321=item getsockopt() on closed socket %s
2322
be771a83
GS
2323(W closed) You tried to get a socket option on a closed socket. Did you
2324forget to check the return value of your socket() call? See
6df41af2
GS
2325L<perlfunc/getsockopt>.
2326
0f539b13
BF
2327=item given is experimental
2328
675fa9ff
FC
2329(S experimental::smartmatch) C<given> depends on smartmatch, which
2330is experimental, so its behavior may change or even be removed
2331in any future release of perl. See the explanation under
2332L<perlsyn/Experimental Details on given and when>.
0f539b13 2333
68567d27
FC
2334=item Global symbol "%s" requires explicit package name (did you forget to
2335declare "my %s"?)
6df41af2 2336
a4edf47d 2337(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2338that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2339declared beforehand using "our", or explicitly qualified to say
2340which package the global variable is in (using "::").
6df41af2 2341
e476b1b5
GS
2342=item glob failed (%s)
2343
5ead438e 2344(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2345for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2346pattern that caused the external program to fail and exit with a
be771a83 2347nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2348resulted in a coredump, this may also mean that your csh (C shell)
2349is broken. If so, you should change all of the csh-related variables
2350in config.sh: If you have tcsh, make the variables refer to it as
2351if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2352all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2353think csh is missing. In either case, after editing config.sh, run
75b44862 2354C<./Configure -S> and rebuild Perl.
e476b1b5 2355
a0d0e21e
LW
2356=item Glob not terminated
2357
2358(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2359a term, so it's looking for the corresponding right angle bracket, and
2360not finding it. Chances are you left some needed parentheses out
2361earlier in the line, and you really meant a "less than".
a0d0e21e 2362
b35b96b6
JH
2363=item gmtime(%f) failed
2364
2365(W overflow) You called C<gmtime> with a number that it could not handle:
2366too large, too small, or NaN. The returned value is C<undef>.
2367
bcd05b94 2368=item gmtime(%f) too large
8b56d6ff 2369
e9200be3 2370(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2371it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2372date. This warning is also triggered with NaN (the special
fc003d4b
MS
2373not-a-number value).
2374
bcd05b94 2375=item gmtime(%f) too small
fc003d4b 2376
e9200be3 2377(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2378it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2379
6df41af2 2380=item Got an error from DosAllocMem
a0d0e21e 2381
6df41af2
GS
2382(P) An error peculiar to OS/2. Most probably you're using an obsolete
2383version of Perl, and this should not happen anyway.
a0d0e21e
LW
2384
2385=item goto must have label
2386
2387(F) Unlike with "next" or "last", you're not allowed to goto an
2388unspecified destination. See L<perlfunc/goto>.
2389
6651ba0b
FC
2390=item Goto undefined subroutine%s
2391
2392(F) You tried to call a subroutine with C<goto &sub> syntax, but
2393the indicated subroutine hasn't been defined, or if it was, it
2394has since been undefined.
2395
6fbc9859 2396=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2397S<<-- HERE> in m/%s/
1f4f6bf1
YO
2398
2399(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2400they must start with a non-digit word character. A common cause of
2401this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2402
5a25739d
FC
2403=item ()-group starts with a count
2404
2405(F) A ()-group started with a count. A count is supposed to follow
2406something: a template character or a ()-group. See L<perlfunc/pack>.
2407
fe13d51d 2408=item %s had compilation errors.
6df41af2
GS
2409
2410(F) The final summary message when a C<perl -c> fails.
2411
a0d0e21e
LW
2412=item Had to create %s unexpectedly
2413
be771a83
GS
2414(S internal) A routine asked for a symbol from a symbol table that ought
2415to have existed already, but for some reason it didn't, and had to be
2416created on an emergency basis to prevent a core dump.
a0d0e21e 2417
6df41af2
GS
2418=item %s has too many errors
2419
2420(F) The parser has given up trying to parse the program after 10 errors.
2421Further error messages would likely be uninformative.
2422
cc4d09e1
KW
2423=item Having more than one /%c regexp modifier is deprecated
2424
2425(D deprecated, regexp) You used the indicated regular expression pattern
2426modifier at least twice in a string of modifiers. It is deprecated to
2427do this with this particular modifier, to allow future extensions to the
2428Perl language.
2429
61e61fbc
JH
2430=item Hexadecimal float: exponent overflow
2431
d8f2b442 2432(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2433than the floating point supports.
2434
2435=item Hexadecimal float: exponent underflow
2436
d8f2b442 2437(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2438than the floating point supports.
2439
5488d373 2440=item Hexadecimal float: internal error (%s)
cf4f6003
JH
2441
2442(F) Something went horribly bad in hexadecimal float handling.
2443
61e61fbc
JH
2444=item Hexadecimal float: mantissa overflow
2445
2446(W overflow) The hexadecimal floating point literal had more bits in
2447the mantissa (the part between the 0x and the exponent, also known as
2448the fraction or the significand) than the floating point supports.
2449
40bca5ae
JH
2450=item Hexadecimal float: precision loss
2451
2452(W overflow) The hexadecimal floating point had internally more
2453digits than could be output. This can be caused by unsupported
2454long double formats, or by 64-bit integers not being available
2455(needed to retrieve the digits under some configurations).
2456
2457=item Hexadecimal float: unsupported long double format
2458
2459(F) You have configured Perl to use long doubles but
d8f2b442 2460the internals of the long double format are unknown;
40bca5ae
JH
2461therefore the hexadecimal float output is impossible.
2462
252aa082
JH
2463=item Hexadecimal number > 0xffffffff non-portable
2464
e476b1b5 2465(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2466(4294967295) and therefore non-portable between systems. See
2467L<perlport> for more on portability concerns.
252aa082 2468
8903cb82
PP
2469=item Identifier too long
2470
2471(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2472about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2473names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2474of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2475
e0e4a6e3
FC
2476=item Ignoring zero length \N{} in character class in regex; marked by
2477S<<-- HERE> in m/%s/
fc8cd66c 2478
f3ba6905 2479(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2480zero-length sequence. When such an escape is used in a character
2481class its behavior is not well defined. Check that the correct
2482escape has been used, and the correct charname handler is in scope.
fc8cd66c 2483
6df41af2 2484=item Illegal binary digit %s
f675dbe5 2485
6df41af2 2486(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2487
6df41af2 2488=item Illegal binary digit %s ignored
a0d0e21e 2489
be771a83
GS
2490(W digit) You may have tried to use a digit other than 0 or 1 in a
2491binary number. Interpretation of the binary number stopped before the
2492offending digit.
a0d0e21e 2493
6597eb22
FC
2494=item Illegal character after '_' in prototype for %s : %s
2495
e4d150f1
FC
2496(W illegalproto) An illegal character was found in a prototype
2497declaration. The '_' in a prototype must be followed by a ';',
2498indicating the rest of the parameters are optional, or one of '@'
2499or '%', since those two will accept 0 or more final parameters.
6597eb22 2500
78d0fecf 2501=item Illegal character \%o (carriage return)
4fdae800 2502
d5898338 2503(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2504would any other whitespace, which means you should never see this error
2505when Perl was built using standard options. For some reason, your
2506version of Perl appears to have been built without this support. Talk
2507to your Perl administrator.
4fdae800 2508
d37a9538
ST
2509=item Illegal character in prototype for %s : %s
2510
197afce1 2511(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2512Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2513Perhaps you were trying to write a subroutine signature but didn't enable
2514that feature first (C<use feature 'signatures'>), so your signature was
2515instead interpreted as a bad prototype.
d37a9538 2516
904d85c5
RGS
2517=item Illegal declaration of anonymous subroutine
2518
2519(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2520you must always specify a block of code. See L<perlsub>.
904d85c5 2521
8e742a20
MHM
2522=item Illegal declaration of subroutine %s
2523
6903afa2 2524(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2525
a0d0e21e
LW
2526=item Illegal division by zero
2527
be771a83
GS
2528(F) You tried to divide a number by 0. Either something was wrong in
2529your logic, or you need to put a conditional in to guard against
2530meaningless input.
a0d0e21e 2531
6df41af2
GS
2532=item Illegal hexadecimal digit %s ignored
2533
be771a83
GS
2534(W digit) You may have tried to use a character other than 0 - 9 or
2535A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2536number stopped before the illegal character.
6df41af2 2537
a0d0e21e
LW
2538=item Illegal modulus zero
2539
be771a83
GS
2540(F) You tried to divide a number by 0 to get the remainder. Most
2541numbers don't take to this kindly.
a0d0e21e 2542
6df41af2 2543=item Illegal number of bits in vec
399388f4 2544
6df41af2
GS
2545(F) The number of bits in vec() (the third argument) must be a power of
2546two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2547
2548=item Illegal octal digit %s
a0d0e21e 2549
d1be9408 2550(F) You used an 8 or 9 in an octal number.
a0d0e21e 2551
399388f4 2552=item Illegal octal digit %s ignored
748a9306 2553
d1be9408 2554(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2555Interpretation of the octal number stopped before the 8 or 9.
748a9306 2556
e0e4a6e3 2557=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2558
675fa9ff 2559(F) You wrote something like
c608e803
KW
2560
2561 (?+foo)
2562
2563The C<"+"> is valid only when followed by digits, indicating a
2564capturing group. See
2565L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2566
375ed12a
JH
2567=item Illegal suidscript
2568
2569(F) The script run under suidperl was somehow illegal.
2570
fe13d51d 2571=item Illegal switch in PERL5OPT: -%c
6ff81951 2572
6df41af2 2573(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2574following switches: B<-[CDIMUdmtw]>.
6ff81951 2575
4003ea29
KW
2576=item Illegal user-defined property name
2577
2578(F) You specified a Unicode-like property name in a regular expression
2579pattern (using C<\p{}> or C<\P{}>) that Perl knows isn't an official
2580Unicode property, and was likely meant to be a user-defined property
2581name, but it can't be one of those, as they must begin with either C<In>
2582or C<Is>. Check the spelling. See also
2583L</Can't find Unicode property definition "%s">.
2584
6df41af2 2585=item Ill-formed CRTL environ value "%s"
81e118e0 2586
75b44862 2587(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2588internal environ array, and encountered an element without the C<=>
2589delimiter used to separate keys from values. The element is ignored.
09bef843 2590
6df41af2 2591=item Ill-formed message in prime_env_iter: |%s|
54310121 2592
be771a83
GS
2593(W internal) A warning peculiar to VMS. Perl tried to read a logical
2594name or CLI symbol definition when preparing to iterate over %ENV, and
2595didn't see the expected delimiter between key and value, so the line was
2596ignored.
54310121 2597
6df41af2 2598=item (in cleanup) %s
9607fc9c 2599
be771a83
GS
2600(W misc) This prefix usually indicates that a DESTROY() method raised
2601the indicated exception. Since destructors are usually called by the
2602system at arbitrary points during execution, and often a vast number of
2603times, the warning is issued only once for any number of failures that
2604would otherwise result in the same message being repeated.
6df41af2 2605
be771a83
GS
2606Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2607also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2608
e0e4a6e3
FC
2609=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2610in m/%s/
0d0b4b3b 2611
675fa9ff 2612(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2613expression inside the construct was completely empty, or if there are
2614too many or few operands for the number of operators. Perl is not smart
2615enough to give you a more precise indication as to what is wrong.
2616
6fbc9859
MH
2617=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2618parent '%s'
2c7d6b9c
RGS
2619
2620(F) The method resolution order (MRO) of the given class is not
2621C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2622documentation in L<mro> for more information.
2623
6a2ed79a 2624=item Infinite recursion in regex
1a147d38
YO
2625
2626(F) You used a pattern that references itself without consuming any input
6903afa2 2627text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2628either consume text or fail.
2629
6dbe9451
NC
2630=item Initialization of state variables in list context currently forbidden
2631
6903afa2
FC
2632(F) Currently the implementation of "state" only permits the
2633initialization of scalar variables in scalar context. Re-write
2634C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2635context. Constructions such as C<state (@a) = foo()> will be
2636supported in a future perl release.
6dbe9451 2637
2186f873
FC
2638=item %%s[%s] in scalar context better written as $%s[%s]
2639
2640(W syntax) In scalar context, you've used an array index/value slice
2641(indicated by %) to select a single element of an array. Generally
2642it's better to ask for a scalar value (indicated by $). The difference
2643is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2644returns and when evaluating its argument, while C<%foo[&bar]> provides
2645a list context to its subscript, which can do weird things if you're
2646expecting only one subscript. When called in list context, it also
2647returns the index (what C<&bar> returns) in addition to the value.
2648
2649=item %%s{%s} in scalar context better written as $%s{%s}
2650
2651(W syntax) In scalar context, you've used a hash key/value slice
2652(indicated by %) to select a single element of a hash. Generally it's
2653better to ask for a scalar value (indicated by $). The difference
2654is that C<$foo{&bar}> always behaves like a scalar, both in the value
2655it returns and when evaluating its argument, while C<@foo{&bar}> and
2656provides a list context to its subscript, which can do weird things
2657if you're expecting only one subscript. When called in list context,
2658it also returns the key in addition to the value.
2659
817e3e2c
TC
2660=item Invalid number '%s' for -C option.
2661
29d76410 2662(F) You supplied a number to the -C option that either has extra leading
817e3e2c
TC
2663zeroes or overflows perl's unsigned integer representation.
2664
fb10a8a7
TC
2665=item %s() is deprecated on :utf8 handles
2666
2667(W deprecated) The sysread(), recv(), syswrite() and send() operators
2668are deprecated on handles that have the C<:utf8> layer, either
2669explicitly, or implicitly, eg., with the C<:encoding(UTF-16LE)> layer.
2670
2671Both sysread() and recv() currently use only the C<:utf8> flag for the
2672stream, ignoring the actual layers. Since sysread() and recv() do no
2673UTF-8 validation they can end up creating invalidly encoded scalars.
2674
2675Similarly, syswrite() and send() use only the C<:utf8> flag, otherwise
2676ignoring any layers. If the flag is set, both write the value UTF-8
2677encoded, even if the layer is some different encoding, such as the
2678example above.
2679
2680Ideally, all of these operators would completely ignore the C<:utf8>
2681state, working only with bytes, but this would result in silently
2682breaking existing code. To avoid this a future version of perl will
2683throw an exception when any of sysread(), recv(), syswrite() or send()
2684are called on handle with the C<:utf8> layer.
2685
a0d0e21e
LW
2686=item Insecure dependency in %s
2687
8b1a09fc 2688(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2689The tainting mechanism is turned on when you're running setuid or
2690setgid, or when you specify B<-T> to turn it on explicitly. The
2691tainting mechanism labels all data that's derived directly or indirectly
2692from the user, who is considered to be unworthy of your trust. If any
2693such data is used in a "dangerous" operation, you get this error. See
2694L<perlsec> for more information.
a0d0e21e
LW
2695
2696=item Insecure directory in %s
2697
be771a83
GS
2698(F) You can't use system(), exec(), or a piped open in a setuid or
2699setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2700the world. Also, the PATH must not contain any relative directory.
2701See L<perlsec>.
a0d0e21e 2702
62f468fc 2703=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2704
2705(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2706setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2707C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2708supplied (or potentially supplied) by the user. The script must set
2709the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2710
0e9be77f
DM
2711=item Insecure user-defined property %s
2712
2713(F) Perl detected tainted data when trying to compile a regular
2714expression that contains a call to a user-defined character property
2715function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2716See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2717
b9ef414d
FC
2718=item Integer overflow in format string for %s
2719
2720(F) The indexes and widths specified in the format string of C<printf()>
2721or C<sprintf()> are too large. The numbers must not overflow the size of
2722integers for your architecture.
2723
a7ae9550
GS
2724=item Integer overflow in %s number
2725
35928bc5 2726(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2727either as a literal or as an argument to hex() or oct() is too big for
2728your architecture, and has been converted to a floating point number.
2729On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2730representable without overflow is 0xFFFFFFFF, 037777777777, or
27310b11111111111111111111111111111111 respectively. Note that Perl
2732transparently promotes all numbers to a floating point representation
2733internally--subject to loss of precision errors in subsequent
2734operations.
bbce6d69 2735
fc89ca81
FC
2736=item Integer overflow in srand
2737
2738(S overflow) The number you have passed to srand is too big to fit
2739in your architecture's integer representation. The number has been
2740replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2741architectures). This means you may be getting less randomness than
2742you expect, because different random seeds above the maximum will
2743return the same sequence of random numbers.
2744
46314c13
JP
2745=item Integer overflow in version
2746
18da5252
FC
2747=item Integer overflow in version %d
2748
784d71ed
FC
2749(W overflow) Some portion of a version initialization is too large for
2750the size of integers for your architecture. This is not a warning
f084e84f 2751because there is no rational reason for a version to try and use an
784d71ed
FC
2752element larger than typically 2**32. This is usually caused by trying
2753to use some odd mathematical operation as a version, like 100/9.
46314c13 2754
e0e4a6e3 2755=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2756
2757(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2758The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2759discovered.
2760
748a9306
LW
2761=item Internal inconsistency in tracking vforks
2762
be771a83
GS
2763(S) A warning peculiar to VMS. Perl keeps track of the number of times
2764you've called C<fork> and C<exec>, to determine whether the current call
2765to C<exec> should affect the current script or a subprocess (see
2766L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2767Perl is making a guess and treating this C<exec> as a request to
2768terminate the Perl script and execute the specified command.
748a9306 2769
870978ae
FC
2770=item internal %<num>p might conflict with future printf extensions
2771
2772(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2773formatting follows a slightly different set of rules when called from
2774C or XS code. Specifically, formats consisting of digits followed
2775by "p" (e.g., "%7p") are reserved for future use. If you see this
2776message, then an XS module tried to call that routine with one such
2777reserved format.
2778
e0e4a6e3 2779=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2780
fa816bf3 2781(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2782S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2783discovered.
a0d0e21e 2784
6df41af2
GS
2785=item %s (...) interpreted as function
2786
75b44862 2787(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2788followed by parentheses turns into a function, with all the list
64977eb6 2789operators arguments found inside the parentheses. See
13a2d996 2790L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2791
f51551f7
FC
2792=item In '(?...)', the '(' and '?' must be adjacent in regex;
2793marked by S<<-- HERE> in m/%s/
2794
2795(F) The two-character sequence C<"(?"> in this context in a regular
2796expression pattern should be an indivisible token, with nothing
2797intervening between the C<"("> and the C<"?">, but you separated them
2798with whitespace.
2799
09bef843
SB
2800=item Invalid %s attribute: %s
2801
a4a4c9e2 2802(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2803by Perl or by a user-supplied handler. See L<attributes>.
2804
2805=item Invalid %s attributes: %s
2806
a4a4c9e2 2807(F) The indicated attributes for a subroutine or variable were not
be771a83 2808recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2809
e0e4a6e3
FC
2810=item Invalid character in charnames alias definition; marked by
2811S<<-- HERE> in '%s
225fb84f
KW
2812
2813(F) You tried to create a custom alias for a character name, with
2814the C<:alias> option to C<use charnames> and the specified character in
2815the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2816
c8028aa6
TC
2817=item Invalid \0 character in %s for %s: %s\0%s
2818
fa3234e3
FC
2819(W syscalls) Embedded \0 characters in pathnames or other system call
2820arguments produce a warning as of 5.20. The parts after the \0 were
2821formerly ignored by system calls.
c8028aa6 2822
e0e4a6e3 2823=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2824
2825(F) Only certain characters are valid for character names. The
2826indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2827
c635e13b
PP
2828=item Invalid conversion in %s: "%s"
2829
be771a83
GS
2830(W printf) Perl does not understand the given format conversion. See
2831L<perlfunc/sprintf>.
c635e13b 2832
e0e4a6e3
FC
2833=item Invalid escape in the specified encoding in regex; marked by
2834S<<-- HERE> in m/%s/
9e08bc66 2835
98d31c73 2836(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2837didn't correspond to a single character through the conversion
2838from the encoding specified by the encoding pragma.
98d31c73
FC
2839The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2840instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2841The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2842escape was discovered.
2843
8149aa9f
FC
2844=item Invalid hexadecimal number in \N{U+...}
2845
e0e4a6e3
FC
2846=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2847S<<-- HERE> in m/%s/
aec0ef10 2848
8149aa9f 2849(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2850number. Either it is empty, or you tried to use a character other than
28510 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2852
6651ba0b
FC
2853=item Invalid module name %s with -%c option: contains single ':'
2854
2855(F) The module argument to perl's B<-m> and B<-M> command-line options
2856cannot contain single colons in the module name, but only in the
2857arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2858B<-MFoo:Bar=baz> is not.
2859
2c7d6b9c
RGS
2860=item Invalid mro name: '%s'
2861
162a3e34
FC
2862(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2863where C<foo> is not a valid method resolution order (MRO). Currently,
2864the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2865a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2866
40e4140b
FC
2867=item Invalid negative number (%s) in chr
2868
2869(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2870not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2871character (U+FFFD).
2872
6651ba0b
FC
2873=item invalid option -D%c, use -D'' to see choices
2874
8ff21bfe
FC
2875(S debugging) Perl was called with invalid debugger flags. Call perl
2876with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2877See also L<perlrun/-Dletters>.
6651ba0b 2878
6e8a73f2 2879=item Invalid quantifier in {,} in regex; marked by S<<-- HERE> in m/%s/
35cd12d1
HS
2880
2881(F) The pattern looks like a {min,max} quantifier, but the min or max
2882could not be parsed as a valid number - either it has leading zeroes,
2883or it represents too big a number to cope with. The S<<-- HERE> shows
2884where in the regular expression the problem was discovered. See L<perlre>.
2885
e0e4a6e3 2886=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2887
2888(F) The range specified in a character class had a minimum character
7253e4e3
RK
2889greater than the maximum character. One possibility is that you forgot the
2890C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2891up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2892problem was discovered. See L<perlre>.
6df41af2 2893
d1573ac7 2894=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2895
2896(F) The range specified in the tr/// or y/// operator had a minimum
2897character greater than the maximum character. See L<perlop>.
2898
09bef843
SB
2899=item Invalid separator character %s in attribute list
2900
0120eecf 2901(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2902elements of an attribute list. If the previous attribute had a
2903parenthesised parameter list, perhaps that list was terminated too soon.
2904See L<attributes>.
09bef843 2905
b4581f09
JH
2906=item Invalid separator character %s in PerlIO layer specification %s
2907
2bfc5f71
FC
2908(W layer) When pushing layers onto the Perl I/O system, something other
2909than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2910If the previous attribute had a parenthesised parameter list, perhaps that
2911list was terminated too soon.
2912
2c86d456
DG
2913=item Invalid strict version format (%s)
2914
fa816bf3 2915(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2916A "strict" version number is a positive decimal number (integer or
2917decimal-fraction) without exponentiation or else a dotted-decimal
2918v-string with a leading 'v' character and at least three components.
a6485a24 2919The parenthesized text indicates which criteria were not met.
2c86d456
DG
2920See the L<version> module for more details on allowed version formats.
2921
49704364 2922=item Invalid type '%s' in %s
96e4d5b1 2923
49704364
LW
2924(F) The given character is not a valid pack or unpack type.
2925See L<perlfunc/pack>.
6728c851 2926
49704364 2927(W) The given character is not a valid pack or unpack type but used to be
75b44862 2928silently ignored.
96e4d5b1 2929
2c86d456
DG
2930=item Invalid version format (%s)
2931
fa816bf3 2932(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2933A "lax" version number is a positive decimal number (integer or
2934decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2935v-string. If the v-string has fewer than three components, it
2936must have a leading 'v' character. Otherwise, the leading 'v' is
2937optional. Both decimal and dotted-decimal versions may have a
2938trailing "alpha" component separated by an underscore character
2939after a fractional or dotted-decimal component. The parenthesized
2940text indicates which criteria were not met. See the L<version> module
2941for more details on allowed version formats.
46314c13 2942
798ae1b7
DG
2943=item Invalid version object
2944
fa816bf3
FC
2945(F) The internal structure of the version object was invalid.
2946Perhaps the internals were modified directly in some way or
2947an arbitrary reference was blessed into the "version" class.
798ae1b7 2948
cd209d9d 2949=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2950marked by S<<-- HERE> in m/%s/
675fa9ff 2951
cd209d9d 2952(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2953this context in a regular expression pattern should be an
2954indivisible token, with nothing intervening between the C<"(">
cd209d9d 2955and the C<"*">, but you separated them.
675fa9ff 2956
a0d0e21e
LW
2957=item ioctl is not implemented
2958
2959(F) Your machine apparently doesn't implement ioctl(), which is pretty
2960strange for a machine that supports C.
2961
c289d2f7
JH
2962=item ioctl() on unopened %s
2963
2964(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2965Check your control flow and number of arguments.
c289d2f7 2966
fe13d51d 2967=item IO layers (like '%s') unavailable
363c40c4
SB
2968
2969(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2970you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2971with 'useperlio'.
2972
80cbd5ad
JH
2973=item IO::Socket::atmark not implemented on this architecture
2974
2975(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2976neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2977
6e8a73f2 2978=item '%s' is an unknown bound type in regex; marked by S<<-- HERE> in m/%s/
64935bc6
KW
2979
2980(F) You used C<\b{...}> or C<\B{...}> and the C<...> is not known to
2981Perl. The current valid ones are given in
2982L<perlrebackslash/\b{}, \b, \B{}, \B>.
2983
6e8a73f2 2984=item "%s" is more clearly written simply as "%s" in regex; marked by S<<-- HERE> in m/%s/
acdfc3b6
KW
2985
2986(W regexp) (only under C<S<use re 'strict'>> or within C<(?[...])>)
2987
2988You specified a character that has the given plainer way of writing it,
2989and which is also portable to platforms running with different character
2990sets.
2991
4f650b80 2992=item $* is no longer supported
b4581f09 2993
4f650b80 2994(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2995perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2996previous versions of perl the use of C<$*> enabled or disabled multi-line
2997matching within a string.
4fd19576
B
2998
2999Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
3000modifiers. You can enable C</m> for a lexical scope (even a whole file)
3001with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 3002then all regular expressions behaved as if they were written using C</m>.)
b4581f09 3003
8ae1fe26
RGS
3004=item $# is no longer supported
3005
a58ac25e 3006(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 3007perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 3008should use the printf/sprintf functions instead.
8ae1fe26 3009
ccf3535a 3010=item '%s' is not a code reference
6ad11d81 3011
6903afa2
FC
3012(W overload) The second (fourth, sixth, ...) argument of
3013overload::constant needs to be a code reference. Either
3014an anonymous subroutine, or a reference to a subroutine.
6ad11d81 3015
ccf3535a 3016=item '%s' is not an overloadable type
6ad11d81 3017
04a80ee0
RGS
3018(W overload) You tried to overload a constant type the overload package is
3019unaware of.
6ad11d81 3020
5a25739d
FC
3021=item -i used with no filenames on the command line, reading from STDIN
3022
3023(S inplace) The C<-i> option was passed on the command line, indicating
3024that the script is intended to edit files in place, but no files were
3025given. This is usually a mistake, since editing STDIN in place doesn't
3026make sense, and can be confusing because it can make perl look like
3027it is hanging when it is really just trying to read from STDIN. You
3028should either pass a filename to edit, or remove C<-i> from the command
3029line. See L<perlrun> for more details.
3030
aec0ef10 3031=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
3032
3033(P) The regular expression parser is confused.
3034
3035=item Label not found for "last %s"
3036
be771a83
GS
3037(F) You named a loop to break out of, but you're not currently in a loop
3038of that name, not even if you count where you were called from. See
3039L<perlfunc/last>.
a0d0e21e
LW
3040
3041=item Label not found for "next %s"
3042
3043(F) You named a loop to continue, but you're not currently in a loop of
3044that name, not even if you count where you were called from. See
3045L<perlfunc/last>.
3046
3047=item Label not found for "redo %s"
3048
3049(F) You named a loop to restart, but you're not currently in a loop of
3050that name, not even if you count where you were called from. See
3051L<perlfunc/last>.
3052
85ab1d1d 3053=item leaving effective %s failed
5ff3f7a4 3054
85ab1d1d 3055(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
3056effective uids or gids failed.
3057
49704364
LW
3058=item length/code after end of string in unpack
3059
d7f8936a 3060(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
3061length/code combination tried to obtain more data. This results in
3062an undefined value for the length. See L<perlfunc/pack>.
49704364 3063
25e26107 3064=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 3065
0d46a4e7
FC
3066(W syntax) You used length() on either an array or a hash when you
3067probably wanted a count of the items.
e508c8a4
MH
3068
3069Array size can be obtained by doing:
3070
3071 scalar(@array);
3072
3073The number of items in a hash can be obtained by doing:
3074
3075 scalar(keys %hash);
3076
f0e67a1d
Z
3077=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
3078
d4fe7078
RS
3079(F) An extension is attempting to insert text into the current parse
3080(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
3081couldn't be part of the current input. This is an inherent pitfall
3082of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 3083it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
3084
3085=item Lexing code internal error (%s)
3086
3087(F) Lexing code supplied by an extension violated the lexer's API in a
3088detectable way.
3089
69282e91 3090=item listen() on closed socket %s
a0d0e21e 3091
be771a83
GS
3092(W closed) You tried to do a listen on a closed socket. Did you forget
3093to check the return value of your socket() call? See
3094L<perlfunc/listen>.
a0d0e21e 3095
6651ba0b
FC
3096=item List form of piped open not implemented
3097
3098(F) On some platforms, notably Windows, the three-or-more-arguments
3099form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
3100Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
3101
dc6bb7ba
FC
3102=item %s: loadable library and perl binaries are mismatched (got handshake key %p, needed %p)
3103
3104(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
3105process that was built against a different build of perl than the
3106said library was compiled against. Reinstalling the XS module will
3107likely fix this error.
3108
8c6180a9
KW
3109=item Locale '%s' may not work well.%s
3110
780fcc9f 3111(W locale) You are using the named locale, which is a non-UTF-8 one, and
dae67c56
KW
3112which perl has determined is not fully compatible with what it can
3113handle. The second C<%s> gives a reason.
8c6180a9
KW
3114
3115By far the most common reason is that the locale has characters in it
3116that are represented by more than one byte. The only such locales that
3117Perl can handle are the UTF-8 locales. Most likely the specified locale
3118is a non-UTF-8 one for an East Asian language such as Chinese or
3119Japanese. If the locale is a superset of ASCII, the ASCII portion of it
780fcc9f 3120may work in Perl.
8c6180a9
KW
3121
3122Some essentially obsolete locales that aren't supersets of ASCII, mainly
3123those in ISO 646 or other 7-bit locales, such as ASMO 449, can also have
3124problems, depending on what portions of the ASCII character set get
3125changed by the locale and are also used by the program.
3126The warning message lists the determinable conflicting characters.
3127
780fcc9f
KW
3128Note that not all incompatibilities are found.
3129
3130If this happens to you, there's not much you can do except switch to use a
3131different locale or use L<Encode> to translate from the locale into
3132UTF-8; if that's impracticable, you have been warned that some things
3133may break.
3134
3135This message is output once each time a bad locale is switched into
3136within the scope of C<S<use locale>>, or on the first possibly-affected
3137operation if the C<S<use locale>> inherits a bad one. It is not raised
3138for any operations from the L<POSIX> module.
3139
a2162cd9
FC
3140=item localtime(%f) failed
3141
3142(W overflow) You called C<localtime> with a number that it could not handle:
3143too large, too small, or NaN. The returned value is C<undef>.
3144
3145=item localtime(%f) too large
3146
3147(W overflow) You called C<localtime> with a number that was larger
3148than it can reliably handle and C<localtime> probably returned the
3149wrong date. This warning is also triggered with NaN (the special
3150not-a-number value).
3151
3152=item localtime(%f) too small
3153
3154(W overflow) You called C<localtime> with a number that was smaller
3155than it can reliably handle and C<localtime> probably returned the
3156wrong date.
3157
58e23c8d 3158=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
3159
3160(F) There is currently a limit on the length of string which lookbehind can
6903afa2 3161handle. This restriction may be eased in a future release.
2e50fd82 3162
b88df990
NC
3163=item Lost precision when %s %f by 1
3164
e63e8a91
FC
3165(W imprecision) The value you attempted to increment or decrement by one
3166is too large for the underlying floating point representation to store
3167accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
3168warning because it has already switched from integers to floating point
3169when values are too large for integers, and now even floating point is
3170insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 3171
93fad930 3172=item lstat() on filehandle%s
2f7da168
RK
3173
3174(W io) You tried to do an lstat on a filehandle. What did you mean
3175by that? lstat() makes sense only on filenames. (Perl did a fstat()
3176instead on the filehandle.)
3177
345d70e3 3178=item lvalue attribute %s already-defined subroutine
bb3abb05 3179
345d70e3
FC
3180(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
3181attribute on or off on a Perl subroutine that is already defined
3182does not always work properly. It may or may not do what you
3183want, depending on what code is inside the subroutine, with exact
3184details subject to change between Perl versions. Only do this
3185if you really know what you are doing.
bb3abb05 3186
885ef6f5
GG
3187=item lvalue attribute ignored after the subroutine has been defined
3188
345d70e3
FC
3189(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3190subroutine an lvalue subroutine after it has been defined is
3191not permitted. To make the subroutine an lvalue subroutine,
3192add the lvalue attribute to the definition, or put the C<sub
3193foo :lvalue;> declaration before the definition.
3194
3195See also L<attributes.pm|attributes>.
885ef6f5 3196
6f1b3ab0
FC
3197=item Magical list constants are not supported
3198
3199(F) You assigned a magical array to a stash element, and then tried
3200to use the subroutine from the same slot. You are asking Perl to do
3201something it cannot do, details subject to change between Perl versions.
3202
2db62bbc 3203=item Malformed integer in [] in pack
49704364 3204
2db62bbc 3205(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3206are permitted. See L<perlfunc/pack>.
3207
3208=item Malformed integer in [] in unpack
3209
2db62bbc 3210(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3211are permitted. See L<perlfunc/pack>.
3212
6df41af2
GS
3213=item Malformed PERLLIB_PREFIX
3214
3215(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3216
3217 prefix1;prefix2
3218
3219or
6df41af2
GS
3220 prefix1 prefix2
3221
be771a83
GS
3222with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3223a builtin library search path, prefix2 is substituted. The error may
3224appear if components are not found, or are too long. See
fecfaeb8 3225"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3226
2f758a16
ST
3227=item Malformed prototype for %s: %s
3228
d37a9538
ST
3229(F) You tried to use a function with a malformed prototype. The
3230syntax of function prototypes is given a brief compile-time check for
3231obvious errors like invalid characters. A more rigorous check is run
3232when the function is called.
30d9c59b
Z
3233Perhaps the function's author was trying to write a subroutine signature
3234but didn't enable that feature first (C<use feature 'signatures'>),
3235so the signature was instead interpreted as a bad prototype.
2f758a16 3236
ba210ebe
JH
3237=item Malformed UTF-8 character (%s)
3238
4d6f11e5 3239(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3240encoding rules, even though it had the UTF8 flag on.
ba210ebe 3241
2575c402
JW
3242One possible cause is that you set the UTF8 flag yourself for data that
3243you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 32448-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3245
3246If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3247sequences are handled gracefully, but if you use C<:utf8>, the flag is
3248set without validating the data, possibly resulting in this error
3249message.
3250
3251See also L<Encode/"Handling Malformed Data">.
901b21bf 3252
107160e2
KW
3253=item Malformed UTF-8 character immediately after '%s'
3254
3255(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3256encoding rules. The message prints out the properly encoded characters
3257just before the first bad one. If C<utf8> warnings are enabled, a
3258warning is generated that gives more details about the type of
3259malformation.
3260
bde9e88d 3261=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3262
3263(F) The charnames handler returned malformed UTF-8.
3264
4a5d3a93
FC
3265=item Malformed UTF-8 string in '%c' format in unpack
3266
3267(F) You tried to unpack something that didn't comply with UTF-8 encoding
3268rules and perl was unable to guess how to make more progress.
3269
f337b084
TH
3270=item Malformed UTF-8 string in pack
3271
3272(F) You tried to pack something that didn't comply with UTF-8 encoding
3273rules and perl was unable to guess how to make more progress.
3274
3275=item Malformed UTF-8 string in unpack
3276
3277(F) You tried to unpack something that didn't comply with UTF-8 encoding
3278rules and perl was unable to guess how to make more progress.
3279
4a5d3a93 3280=item Malformed UTF-16 surrogate
f337b084 3281
4a5d3a93
FC
3282(F) Perl thought it was reading UTF-16 encoded character data but while
3283doing it Perl met a malformed Unicode surrogate.
3284
30d9c59b
Z
3285=item Mandatory parameter follows optional parameter
3286
3287(F) In a subroutine signature, you wrote something like "$a = undef,
3288$b", making an earlier parameter optional and a later one mandatory.
3289Parameters are filled from left to right, so it's impossible for the
3290caller to omit an earlier one and pass a later one. If you want to act
3291as if the parameters are filled from right to left, declare the rightmost
3292optional and then shuffle the parameters around in the subroutine's body.
3293
2d88a86a
KW
3294=item Matched non-Unicode code point 0x%X against Unicode property; may
3295not be portable
3296
3297(S non_unicode) Perl allows strings to contain a superset of
3298Unicode code points; each code point may be as large as what is storable
3299in an unsigned integer on your system, but these may not be accepted by
3300other languages/systems. This message occurs when you matched a string
3301containing such a code point against a regular expression pattern, and
3302the code point was matched against a Unicode property, C<\p{...}> or
3303C<\P{...}>. Unicode properties are only defined on Unicode code points,
3304so the result of this match is undefined by Unicode, but Perl (starting
3305in v5.20) treats non-Unicode code points as if they were typical
3306unassigned Unicode ones, and matched this one accordingly. Whether a
3307given property matches these code points or not is specified in
3308L<perluniprops/Properties accessible through \p{} and \P{}>.
3309
3310This message is suppressed (unless it has been made fatal) if it is
3311immaterial to the results of the match if the code point is Unicode or
3312not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3313the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3314Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3315every code point except these 22.)
3316
3317Getting this message indicates that the outcome of the match arguably
3318should have been the opposite of what actually happened. If you think
3319that is the case, you may wish to make the C<non_unicode> warnings
3320category fatal; if you agree with Perl's decision, you may wish to turn
3321off this category.
3322
3323See L<perlunicode/Beyond Unicode code points> for more information.
3324
e0e4a6e3
FC
3325=item %s matches null string many times in regex; marked by S<<-- HERE> in
3326m/%s/
4a5d3a93
FC
3327
3328(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3329regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3330shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3331See L<perlre>.
f337b084 3332
de42a5a9 3333=item Maximal count of pending signals (%u) exceeded
2563cec5 3334
6903afa2 3335(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3336usually indicates that your operating system tried to deliver signals
3337too fast (with a very high priority), starving the perl process from
3338resources it would need to reach a point where it can process signals
6903afa2 3339safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3340
25f58aea
PN
3341=item "%s" may clash with future reserved word
3342
3343(W) This warning may be due to running a perl5 script through a perl4
3344interpreter, especially if the word that is being warned about is
3345"use" or "my".
3346
0d2487cd 3347=item '%' may not be used in pack
6df41af2
GS
3348
3349(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3350checksumming process loses information, and you can't go the other way.
3351See L<perlfunc/unpack>.
6df41af2 3352
a0d0e21e
LW
3353=item Method for operation %s not found in package %s during blessing
3354
3355(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3356doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3357
3cdd684c
TP
3358=item Method %s not permitted
3359
3360See Server error.
3361
a0d0e21e
LW
3362=item Might be a runaway multi-line %s string starting on line %d
3363
3364(S) An advisory indicating that the previous error may have been caused
3365by a missing delimiter on a string or pattern, because it eventually
3366ended earlier on the current line.
3367
3368=item Misplaced _ in number
3369
d4ced10d
JH
3370(W syntax) An underscore (underbar) in a numeric constant did not
3371separate two digits.
a0d0e21e 3372
7baa4690
HS
3373=item Missing argument in %s
3374
3664866e
AB
3375(W missing) You called a function with fewer arguments than other