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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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192=item Argument list not closed for PerlIO layer "%s"
193
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194(W layer) When pushing a layer with arguments onto the Perl I/O
195system you forgot the ) that closes the argument list. (Layers
196take care of transforming data between external and internal
197representations.) Perl stopped parsing the layer list at this
198point and did not attempt to push this layer. If your program
199didn't explicitly request the failing operation, it may be the
200result of the value of the environment variable PERLIO.
b4581f09 201
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202=item Argument "%s" treated as 0 in increment (++)
203
204(W numeric) The indicated string was fed as an argument to the C<++>
205operator which expects either a number or a string matching
206C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
207Auto-decrement> for details.
208
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209=item assertion botched: %s
210
21b5e840 211(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 212
0eacef8e 213=item Assertion %s failed: file "%s", line %d
a0d0e21e 214
21b5e840 215(X) A general assertion failed. The file in question must be examined.
a0d0e21e 216
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217=item Assigned value is not a reference
218
219(F) You tried to assign something that was not a reference to an lvalue
220reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
221C<\$x = \$y>.
222
223=item Assigned value is not %s reference
224
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225(F) You tried to assign a reference to a reference constructor, but the
226two references were not of the same type. You cannot alias a scalar to
227an array, or an array to a hash; the two types must match.
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228
229 \$x = \@y; # error
230 \@x = \%y; # error
231 $y = [];
232 \$x = $y; # error; did you mean \$y?
233
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234=item Assigning non-zero to $[ is no longer possible
235
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236(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
237the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 238
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239=item Assignment to both a list and a scalar
240
241(F) If you assign to a conditional operator, the 2nd and 3rd arguments
242must either both be scalars or both be lists. Otherwise Perl won't
243know which context to supply to the right side.
244
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245=item <> at require-statement should be quotes
246
247(F) You wrote C<< require <file> >> when you should have written
248C<require 'file'>.
249
2393f1b9 250=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 251
49293501 252(F) The failing code has attempted to get or set a key which is not in
2393f1b9 253the current set of allowed keys of a restricted hash.
49293501 254
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255=item Attempt to bless into a freed package
256
257(F) You wrote C<bless $foo> with one argument after somehow causing
258the current package to be freed. Perl cannot figure out what to
259do, so it throws up in hands in despair.
260
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261=item Attempt to bless into a reference
262
263(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 264the name of the package to bless the resulting object into. You've
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265supplied instead a reference to something: perhaps you wrote
266
267 bless $self, $proto;
268
269when you intended
270
271 bless $self, ref($proto) || $proto;
272
273If you actually want to bless into the stringified version
274of the reference supplied, you need to stringify it yourself, for
275example by:
276
277 bless $self, "$proto";
278
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279=item Attempt to clear deleted array
280
281(S debugging) An array was assigned to when it was being freed.
282Freed values are not supposed to be visible to Perl code. This
283can also happen if XS code calls C<av_clear> from a custom magic
284callback on the array.
285
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286=item Attempt to delete disallowed key '%s' from a restricted hash
287
288(F) The failing code attempted to delete from a restricted hash a key
289which is not in its key set.
290
291=item Attempt to delete readonly key '%s' from a restricted hash
292
293(F) The failing code attempted to delete a key whose value has been
294declared readonly from a restricted hash.
295
de42a5a9 296=item Attempt to free non-arena SV: 0x%x
a0d0e21e 297
f84fe999 298(S internal) All SV objects are supposed to be allocated from arenas
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299that will be garbage collected on exit. An SV was discovered to be
300outside any of those arenas.
a0d0e21e 301
12578ffb 302=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 303
f84fe999 304(S internal) Perl maintains a reference-counted internal table of
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305strings to optimize the storage and access of hash keys and other
306strings. This indicates someone tried to decrement the reference count
307of a string that can no longer be found in the table.
bbce6d69 308
7d5b40b4 309=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 310
f84fe999 311(S debugging) Mortalized values are supposed to be freed by the
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312free_tmps() routine. This indicates that something else is freeing the
313SV before the free_tmps() routine gets a chance, which means that the
314free_tmps() routine will be freeing an unreferenced scalar when it does
315try to free it.
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316
317=item Attempt to free unreferenced glob pointers
318
f84fe999 319(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 320
7d5b40b4 321=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 322
8f7e4d2c 323(S internal) Perl went to decrement the reference count of a scalar to
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324see if it would go to 0, and discovered that it had already gone to 0
325earlier, and should have been freed, and in fact, probably was freed.
326This could indicate that SvREFCNT_dec() was called too many times, or
327that SvREFCNT_inc() was called too few times, or that the SV was
328mortalized when it shouldn't have been, or that memory has been
329corrupted.
a0d0e21e 330
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331=item Attempt to pack pointer to temporary value
332
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333(W pack) You tried to pass a temporary value (like the result of a
334function, or a computed expression) to the "p" pack() template. This
335means the result contains a pointer to a location that could become
336invalid anytime, even before the end of the current statement. Use
337literals or global values as arguments to the "p" pack() template to
338avoid this warning.
84902520 339
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340=item Attempt to reload %s aborted.
341
342(F) You tried to load a file with C<use> or C<require> that failed to
343compile once already. Perl will not try to compile this file again
344unless you delete its entry from %INC. See L<perlfunc/require> and
345L<perlvar/%INC>.
346
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347=item Attempt to set length of freed array
348
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349(W misc) You tried to set the length of an array which has
350been freed. You can do this by storing a reference to the
351scalar representing the last index of an array and later
352assigning through that reference. For example
1b20cd17
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353
354 $r = do {my @a; \$#a};
355 $$r = 503
356
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357=item Attempt to use reference as lvalue in substr
358
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359(W substr) You supplied a reference as the first argument to substr()
360used as an lvalue, which is pretty strange. Perhaps you forgot to
361dereference it first. See L<perlfunc/substr>.
b7a902f4 362
c32124fe
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363=item Attribute "locked" is deprecated
364
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365(D deprecated) You have used the attributes pragma to modify the
366"locked" attribute on a code reference. The :locked attribute is
367obsolete, has had no effect since 5005 threads were removed, and
368will be removed in a future release of Perl 5.
c32124fe 369
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370=item Attribute prototype(%s) discards earlier prototype attribute in same sub
371
372(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
373example. Since each sub can only have one prototype, the earlier
374declaration(s) are discarded while the last one is applied.
375
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376=item Attribute "unique" is deprecated
377
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378(D deprecated) You have used the attributes pragma to modify
379the "unique" attribute on an array, hash or scalar reference.
380The :unique attribute has had no effect since Perl 5.8.8, and
381will be removed in a future release of Perl 5.
f1a3ce43 382
ccce04a4
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383=item av_reify called on tied array
384
385(S debugging) This indicates that something went wrong and Perl got I<very>
386confused about C<@_> or C<@DB::args> being tied.
387
de42a5a9 388=item Bad arg length for %s, is %u, should be %d
a0d0e21e 389
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390(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
391or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 392S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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393S<sizeof(struct shmid_ds *)>.
394
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395=item Bad evalled substitution pattern
396
496a33f5 397(F) You've used the C</e> switch to evaluate the replacement for a
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398substitution, but perl found a syntax error in the code to evaluate,
399most likely an unexpected right brace '}'.
400
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401=item Bad filehandle: %s
402
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403(F) A symbol was passed to something wanting a filehandle, but the
404symbol has no filehandle associated with it. Perhaps you didn't do an
405open(), or did it in another package.
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406
407=item Bad free() ignored
408
be771a83 409(S malloc) An internal routine called free() on something that had never
fa816bf3 410been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 411setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 412
9ea8bc6d 413This message can be seen quite often with DB_File on systems with "hard"
6903afa2 414dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 415which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 416
aa689395
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417=item Bad hash
418
419(P) One of the internal hash routines was passed a null HV pointer.
420
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421=item Badly placed ()'s
422
423(A) You've accidentally run your script through B<csh> instead
424of Perl. Check the #! line, or manually feed your script into
425Perl yourself.
426
a7cb8dae 427=item Bad name after %s
a0d0e21e 428
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429(F) You started to name a symbol by using a package prefix, and then
430didn't finish the symbol. In particular, you can't interpolate outside
431of quotes, so
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432
433 $var = 'myvar';
434 $sym = mypack::$var;
435
436is not the same as
437
438 $var = 'myvar';
439 $sym = "mypack::$var";
440
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441=item Bad plugin affecting keyword '%s'
442
443(F) An extension using the keyword plugin mechanism violated the
444plugin API.
445
4ad56ec9
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446=item Bad realloc() ignored
447
6903afa2
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448(S malloc) An internal routine called realloc() on something that
449had never been malloc()ed in the first place. Mandatory, but can
450be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 451
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452=item Bad symbol for array
453
454(P) An internal request asked to add an array entry to something that
455wasn't a symbol table entry.
456
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457=item Bad symbol for dirhandle
458
459(P) An internal request asked to add a dirhandle entry to something
460that wasn't a symbol table entry.
461
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462=item Bad symbol for filehandle
463
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464(P) An internal request asked to add a filehandle entry to something
465that wasn't a symbol table entry.
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466
467=item Bad symbol for hash
468
469(P) An internal request asked to add a hash entry to something that
470wasn't a symbol table entry.
471
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472=item Bareword found in conditional
473
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474(W bareword) The compiler found a bareword where it expected a
475conditional, which often indicates that an || or && was parsed as part
476of the last argument of the previous construct, for example:
34d09196
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477
478 open FOO || die;
479
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480It may also indicate a misspelled constant that has been interpreted as
481a bareword:
34d09196
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482
483 use constant TYPO => 1;
484 if (TYOP) { print "foo" }
485
486The C<strict> pragma is useful in avoiding such errors.
487
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488=item Bareword "%s" not allowed while "strict subs" in use
489
490(F) With "strict subs" in use, a bareword is only allowed as a
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491subroutine identifier, in curly brackets or to the left of the "=>"
492symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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493
494=item Bareword "%s" refers to nonexistent package
495
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496(W bareword) You used a qualified bareword of the form C<Foo::>, but the
497compiler saw no other uses of that namespace before that point. Perhaps
498you need to predeclare a package?
6df41af2 499
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500=item BEGIN failed--compilation aborted
501
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502(F) An untrapped exception was raised while executing a BEGIN
503subroutine. Compilation stops immediately and the interpreter is
504exited.
a0d0e21e 505
68dc0745
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506=item BEGIN not safe after errors--compilation aborted
507
508(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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509implies a C<BEGIN {}>) after one or more compilation errors had already
510occurred. Since the intended environment for the C<BEGIN {}> could not
511be guaranteed (due to the errors), and since subsequent code likely
512depends on its correct operation, Perl just gave up.
68dc0745 513
c782d7ee 514=item \%d better written as $%d
6df41af2 515
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516(W syntax) Outside of patterns, backreferences live on as variables.
517The use of backslashes is grandfathered on the right-hand side of a
518substitution, but stylistically it's better to use the variable form
519because other Perl programmers will expect it, and it works better if
520there are more than 9 backreferences.
6df41af2 521
252aa082
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522=item Binary number > 0b11111111111111111111111111111111 non-portable
523
e476b1b5 524(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
525(4294967295) and therefore non-portable between systems. See
526L<perlport> for more on portability concerns.
252aa082 527
69282e91 528=item bind() on closed socket %s
a0d0e21e 529
be771a83
GS
530(W closed) You tried to do a bind on a closed socket. Did you forget to
531check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 532
c289d2f7
JH
533=item binmode() on closed filehandle %s
534
535(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 536Check your control flow and number of arguments.
c289d2f7 537
c5a0f51a
JH
538=item Bit vector size > 32 non-portable
539
e476b1b5 540(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 541
043c750c 542=item Bizarre copy of %s
4633a7c4 543
be771a83 544(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 545copiable.
4633a7c4 546
5a25739d
FC
547=item Bizarre SvTYPE [%d]
548
434f489b 549(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
550encountered an invalid data type.
551
f675dbe5
CB
552=item Buffer overflow in prime_env_iter: %s
553
be771a83
GS
554(W internal) A warning peculiar to VMS. While Perl was preparing to
555iterate over %ENV, it encountered a logical name or symbol definition
556which was too long, so it was truncated to the string shown.
f675dbe5 557
a0d0e21e
LW
558=item Callback called exit
559
4929bf7b 560(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
561exited by calling exit.
562
6df41af2 563=item %s() called too early to check prototype
f675dbe5 564
be771a83
GS
565(W prototype) You've called a function that has a prototype before the
566parser saw a definition or declaration for it, and Perl could not check
567that the call conforms to the prototype. You need to either add an
568early prototype declaration for the subroutine in question, or move the
569subroutine definition ahead of the call to get proper prototype
570checking. Alternatively, if you are certain that you're calling the
571function correctly, you may put an ampersand before the name to avoid
572the warning. See L<perlsub>.
f675dbe5 573
56feebad
FC
574=item Calling POSIX::%s() is deprecated
575
576(D deprecated) You called a function whose use is deprecated. See
577the function's name in L<POSIX> for details.
578
0c7df902
JH
579=item Cannot chr %f
580
581(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
582
5dee29d4 583=item Cannot compress %f in pack
0c7df902 584
5dee29d4
JH
585(F) You tried compressing an infinity or not-a-number as an unsigned
586integer with BER, which makes no sense.
0c7df902 587
49704364 588=item Cannot compress integer in pack
0258719b 589
717feafc
JH
590(F) An argument to pack("w",...) was too large to compress.
591The BER compressed integer format can only be used with positive
592integers, and you attempted to compress a very large number (> 1e308).
593See L<perlfunc/pack>.
0258719b 594
49704364 595=item Cannot compress negative numbers in pack
0258719b
NC
596
597(F) An argument to pack("w",...) was negative. The BER compressed integer
598format can only be used with positive integers. See L<perlfunc/pack>.
599
5c1f4d79
NC
600=item Cannot convert a reference to %s to typeglob
601
6903afa2
FC
602(F) You manipulated Perl's symbol table directly, stored a reference
603in it, then tried to access that symbol via conventional Perl syntax.
604The access triggers Perl to autovivify that typeglob, but it there is
605no legal conversion from that type of reference to a typeglob.
5c1f4d79 606
4040665a 607=item Cannot copy to %s
ba2fdce6
NC
608
609(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 610be directly assigned to.
ba2fdce6 611
b5d97229
RGS
612=item Cannot find encoding "%s"
613
614(S io) You tried to apply an encoding that did not exist to a filehandle,
615either with open() or binmode().
616
0c7df902
JH
617=item Cannot pack %f with '%c'
618
5dee29d4 619(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
620which makes no sense.
621
622=item Cannot printf %f with '%c'
623
624(F) You tried printing an infinity or not-a-number as a character (%c),
625which makes no sense. Maybe you meant '%s', or just stringifying it?
626
7355df7e
FC
627=item Cannot set tied @DB::args
628
629(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
630is not supported. (Before this error was added, it used to crash.)
631
ce65bc73
FC
632=item Cannot tie unreifiable array
633
634(P) You somehow managed to call C<tie> on an array that does not
635keep a reference count on its arguments and cannot be made to
636do so. Such arrays are not even supposed to be accessible to
637Perl code, but are only used internally.
638
96ebfdd7
RK
639=item Can only compress unsigned integers in pack
640
641(F) An argument to pack("w",...) was not an integer. The BER compressed
642integer format can only be used with positive integers, and you attempted
643to compress something else. See L<perlfunc/pack>.
644
a0d0e21e
LW
645=item Can't bless non-reference value
646
647(F) Only hard references may be blessed. This is how Perl "enforces"
648encapsulation of objects. See L<perlobj>.
649
dc57907a
RGS
650=item Can't "break" in a loop topicalizer
651
0d863452 652(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 653a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
654
655=item Can't "break" outside a given block
dc57907a 656
0d863452
RH
657(F) You called C<break>, but you're not inside a C<given> block.
658
6df41af2
GS
659=item Can't call method "%s" on an undefined value
660
661(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
662object reference or package name contains an undefined value. Something
663like this will reproduce the error:
6df41af2
GS
664
665 $BADREF = undef;
666 process $BADREF 1,2,3;
667 $BADREF->process(1,2,3);
668
a0d0e21e
LW
669=item Can't call method "%s" on unblessed reference
670
54310121 671(F) A method call must know in what package it's supposed to run. It
be771a83
GS
672ordinarily finds this out from the object reference you supply, but you
673didn't supply an object reference in this case. A reference isn't an
674object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
675
676=item Can't call method "%s" without a package or object reference
677
678(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
679object reference or package name contains an expression that returns a
680defined value which is neither an object reference nor a package name.
72b5445b
GS
681Something like this will reproduce the error:
682
683 $BADREF = 42;
684 process $BADREF 1,2,3;
685 $BADREF->process(1,2,3);
686
dfe378f1
FC
687=item Can't call mro_isa_changed_in() on anonymous symbol table
688
689(P) Perl got confused as to whether a hash was a plain hash or a
690symbol table hash when trying to update @ISA caches.
691
2bf7e7b2
FC
692=item Can't call mro_method_changed_in() on anonymous symbol table
693
694(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
695not attached to the symbol table.
696
a0d0e21e
LW
697=item Can't chdir to %s
698
f703fc96 699(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
700that you can chdir to, possibly because it doesn't exist.
701
0545a864 702=item Can't check filesystem of script "%s" for nosuid
104d25b7 703
be771a83
GS
704(P) For some reason you can't check the filesystem of the script for
705nosuid.
104d25b7 706
22e74366 707=item Can't coerce %s to %s in %s
a0d0e21e
LW
708
709(F) Certain types of SVs, in particular real symbol table entries
55497cff 710(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
711say things like:
712
713 *foo += 1;
714
715You CAN say
716
717 $foo = *foo;
718 $foo += 1;
719
720but then $foo no longer contains a glob.
721
0d863452 722=item Can't "continue" outside a when block
dc57907a 723
0d863452
RH
724(F) You called C<continue>, but you're not inside a C<when>
725or C<default> block.
726
a0d0e21e
LW
727=item Can't create pipe mailbox
728
be771a83
GS
729(P) An error peculiar to VMS. The process is suffering from exhausted
730quotas or other plumbing problems.
a0d0e21e 731
eb64745e
GS
732=item Can't declare %s in "%s"
733
30c282f6
NC
734(F) Only scalar, array, and hash variables may be declared as "my", "our" or
735"state" variables. They must have ordinary identifiers as names.
a0d0e21e 736
fc7debfb
FC
737=item Can't "default" outside a topicalizer
738
739(F) You have used a C<default> block that is neither inside a
740C<foreach> loop nor a C<given> block. (Note that this error is
741issued on exit from the C<default> block, so you won't get the
742error if you use an explicit C<continue>.)
743
6df41af2
GS
744=item Can't do inplace edit: %s is not a regular file
745
be771a83 746(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 747a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 748
a0d0e21e
LW
749=item Can't do inplace edit on %s: %s
750
be771a83
GS
751(S inplace) The creation of the new file failed for the indicated
752reason.
a0d0e21e 753
54310121 754=item Can't do inplace edit without backup
a0d0e21e 755
be771a83
GS
756(F) You're on a system such as MS-DOS that gets confused if you try
757reading from a deleted (but still opened) file. You have to say
758C<-i.bak>, or some such.
a0d0e21e 759
10f9c03d 760=item Can't do inplace edit: %s would not be unique
a0d0e21e 761
e476b1b5 762(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
763characters and Perl was unable to create a unique filename during
764inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 765
a0d0e21e
LW
766=item Can't do waitpid with flags
767
be771a83
GS
768(F) This machine doesn't have either waitpid() or wait4(), so only
769waitpid() without flags is emulated.
a0d0e21e 770
a0d0e21e
LW
771=item Can't emulate -%s on #! line
772
be771a83
GS
773(F) The #! line specifies a switch that doesn't make sense at this
774point. For example, it'd be kind of silly to put a B<-x> on the #!
775line.
a0d0e21e 776
1109a392
MHM
777=item Can't %s %s-endian %ss on this platform
778
779(F) Your platform's byte-order is neither big-endian nor little-endian,
780or it has a very strange pointer size. Packing and unpacking big- or
781little-endian floating point values and pointers may not be possible.
782See L<perlfunc/pack>.
783
a0d0e21e
LW
784=item Can't exec "%s": %s
785
d1be9408 786(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
787named program for the indicated reason. Typical reasons include: the
788permissions were wrong on the file, the file wasn't found in
789C<$ENV{PATH}>, the executable in question was compiled for another
790architecture, or the #! line in a script points to an interpreter that
791can't be run for similar reasons. (Or maybe your system doesn't support
792#! at all.)
a0d0e21e
LW
793
794=item Can't exec %s
795
be771a83
GS
796(F) Perl was trying to execute the indicated program for you because
797that's what the #! line said. If that's not what you wanted, you may
798need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
799
800=item Can't execute %s
801
be771a83
GS
802(F) You used the B<-S> switch, but the copies of the script to execute
803found in the PATH did not have correct permissions.
2a92aaa0 804
6df41af2 805=item Can't find an opnumber for "%s"
2a92aaa0 806
be771a83
GS
807(F) A string of a form C<CORE::word> was given to prototype(), but there
808is no builtin with the name C<word>.
6df41af2 809
56ca2fc0
JH
810=item Can't find %s character property "%s"
811
812(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 813could not be found. Maybe you misspelled the name of the property?
e1b711da 814See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 815for a complete list of available official properties.
56ca2fc0 816
6df41af2
GS
817=item Can't find label %s
818
be771a83
GS
819(F) You said to goto a label that isn't mentioned anywhere that it's
820possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
821
822=item Can't find %s on PATH
823
be771a83
GS
824(F) You used the B<-S> switch, but the script to execute could not be
825found in the PATH.
a0d0e21e 826
6df41af2 827=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 828
be771a83
GS
829(F) You used the B<-S> switch, but the script to execute could not be
830found in the PATH, or at least not with the correct permissions. The
831script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
832
833=item Can't find string terminator %s anywhere before EOF
834
be771a83
GS
835(F) Perl strings can stretch over multiple lines. This message means
836that the closing delimiter was omitted. Because bracketed quotes count
837nesting levels, the following is missing its final parenthesis:
a0d0e21e 838
fb73857a
PP
839 print q(The character '(' starts a side comment.);
840
97b3d10f 841If you're getting this error from a here-document, you may have
b6b8cb97
FC
842included unseen whitespace before or after your closing tag or there
843may not be a linebreak after it. A good programmer's editor will have
844a way to help you find these characters (or lack of characters). See
845L<perlop> for the full details on here-documents.
a0d0e21e 846
660a4616
ST
847=item Can't find Unicode property definition "%s"
848
5f8ad6b6
FC
849(F) You may have tried to use C<\p> which means a Unicode
850property (for example C<\p{Lu}> matches all uppercase
fa816bf3 851letters). If you did mean to use a Unicode property, see
e1b711da 852L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 853for a complete list of available properties. If you didn't
fa816bf3
FC
854mean to use a Unicode property, escape the C<\p>, either by
855C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 856until C<\E>).
660a4616 857
b3647a36 858=item Can't fork: %s
a0d0e21e 859
be771a83
GS
860(F) A fatal error occurred while trying to fork while opening a
861pipeline.
a0d0e21e 862
b3647a36
SR
863=item Can't fork, trying again in 5 seconds
864
c973c02e 865(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
866after five seconds.
867
748a9306
LW
868=item Can't get filespec - stale stat buffer?
869
be771a83
GS
870(S) A warning peculiar to VMS. This arises because of the difference
871between access checks under VMS and under the Unix model Perl assumes.
872Under VMS, access checks are done by filename, rather than by bits in
873the stat buffer, so that ACLs and other protections can be taken into
874account. Unfortunately, Perl assumes that the stat buffer contains all
875the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 876the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
877the device name and FID present in the stat buffer, but this works only
878if you haven't made a subsequent call to the CRTL stat() routine,
879because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
880appears, the name lookup failed, and the access-checking routine gave up
881and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
882routine knows about the Perl C<stat> operator and file tests, so you
883shouldn't ever see this warning in response to a Perl command; it arises
884only if some internal code takes stat buffers lightly.)
748a9306 885
a0d0e21e
LW
886=item Can't get pipe mailbox device name
887
be771a83
GS
888(P) An error peculiar to VMS. After creating a mailbox to act as a
889pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
890
891=item Can't get SYSGEN parameter value for MAXBUF
892
748a9306
LW
893(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
894mailbox buffers to be, and didn't get an answer.
a0d0e21e 895
6df41af2 896=item Can't "goto" into the middle of a foreach loop
a0d0e21e 897
be771a83
GS
898(F) A "goto" statement was executed to jump into the middle of a foreach
899loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
900
901=item Can't "goto" out of a pseudo block
902
be771a83
GS
903(F) A "goto" statement was executed to jump out of what might look like
904a block, except that it isn't a proper block. This usually occurs if
905you tried to jump out of a sort() block or subroutine, which is a no-no.
906See L<perlfunc/goto>.
a0d0e21e 907
5a25739d
FC
908=item Can't goto subroutine from an eval-%s
909
910(F) The "goto subroutine" call can't be used to jump out of an eval
911"string" or block.
912
9850bf21 913=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 914
9850bf21
RH
915(F) The "goto subroutine" call can't be used to jump out of the
916comparison sub for a sort(), or from a similar callback (such
917as the reduce() function in List::Util).
918
6df41af2
GS
919=item Can't goto subroutine outside a subroutine
920
be771a83
GS
921(F) The deeply magical "goto subroutine" call can only replace one
922subroutine call for another. It can't manufacture one out of whole
923cloth. In general you should be calling it out of only an AUTOLOAD
924routine anyway. See L<perlfunc/goto>.
6df41af2 925
0b5b802d
GS
926=item Can't ignore signal CHLD, forcing to default
927
be771a83
GS
928(W signal) Perl has detected that it is being run with the SIGCHLD
929signal (sometimes known as SIGCLD) disabled. Since disabling this
930signal will interfere with proper determination of exit status of child
931processes, Perl has reset the signal to its default value. This
932situation typically indicates that the parent program under which Perl
933may be running (e.g. cron) is being very careless.
0b5b802d 934
e2c0f81f
DG
935=item Can't kill a non-numeric process ID
936
937(F) Process identifiers must be (signed) integers. It is a fatal error to
938attempt to kill() an undefined, empty-string or otherwise non-numeric
939process identifier.
940
6df41af2 941=item Can't "last" outside a loop block
4633a7c4 942
6df41af2 943(F) A "last" statement was executed to break out of the current block,
be771a83
GS
944except that there's this itty bitty problem called there isn't a current
945block. Note that an "if" or "else" block doesn't count as a "loopish"
946block, as doesn't a block given to sort(), map() or grep(). You can
947usually double the curlies to get the same effect though, because the
948inner curlies will be considered a block that loops once. See
949L<perlfunc/last>.
4633a7c4 950
2c7d6b9c
RGS
951=item Can't linearize anonymous symbol table
952
953(F) Perl tried to calculate the method resolution order (MRO) of a
954package, but failed because the package stash has no name.
955
b8170e59
JB
956=item Can't load '%s' for module %s
957
6903afa2
FC
958(F) The module you tried to load failed to load a dynamic extension.
959This may either mean that you upgraded your version of perl to one
960that is incompatible with your old dynamic extensions (which is known
961to happen between major versions of perl), or (more likely) that your
962dynamic extension was built against an older version of the library
963that is installed on your system. You may need to rebuild your old
964dynamic extensions.
b8170e59 965
748a9306
LW
966=item Can't localize lexical variable %s
967
2ba9eb46 968(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
969lexical variable using "my" or "state". This is not allowed. If you
970want to localize a package variable of the same name, qualify it with
971the package name.
748a9306 972
6df41af2 973=item Can't localize through a reference
4727527e 974
6df41af2
GS
975(F) You said something like C<local $$ref>, which Perl can't currently
976handle, because when it goes to restore the old value of whatever $ref
be771a83 977pointed to after the scope of the local() is finished, it can't be sure
64977eb6 978that $ref will still be a reference.
4727527e 979
ea071790 980=item Can't locate %s
ec889f3a 981
fa816bf3
FC
982(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
983Perl looks for the file in all the locations mentioned in @INC, unless
984the file name included the full path to the file. Perhaps you need
985to set the PERL5LIB or PERL5OPT environment variable to say where the
986extra library is, or maybe the script needs to add the library name
be771a83
GS
987to @INC. Or maybe you just misspelled the name of the file. See
988L<perlfunc/require> and L<lib>.
a0d0e21e 989
6df41af2
GS
990=item Can't locate auto/%s.al in @INC
991
be771a83
GS
992(F) A function (or method) was called in a package which allows
993autoload, but there is no function to autoload. Most probable causes
994are a misprint in a function/method name or a failure to C<AutoSplit>
995the file, say, by doing C<make install>.
6df41af2 996
b8170e59
JB
997=item Can't locate loadable object for module %s in @INC
998
999(F) The module you loaded is trying to load an external library, like
d70d8e57 1000for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1001unable to locate this library. See L<DynaLoader>.
1002
a0d0e21e
LW
1003=item Can't locate object method "%s" via package "%s"
1004
1005(F) You called a method correctly, and it correctly indicated a package
1006functioning as a class, but that package doesn't define that particular
2ba9eb46 1007method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1008
8af56b9d
FC
1009=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1010to load "%s"?)
1011
1012(F) You called a method on a class that did not exist, and the method
1013could not be found in UNIVERSAL. This often means that a method
1014requires a package that has not been loaded.
1015
a0d0e21e
LW
1016=item Can't locate package %s for @%s::ISA
1017
be771a83
GS
1018(W syntax) The @ISA array contained the name of another package that
1019doesn't seem to exist.
a0d0e21e 1020
2f7da168
RK
1021=item Can't locate PerlIO%s
1022
1023(F) You tried to use in open() a PerlIO layer that does not exist,
1024e.g. open(FH, ">:nosuchlayer", "somefile").
1025
f4ad53f4 1026=item Can't make list assignment to %ENV on this system
3e3baf6d 1027
be771a83
GS
1028(F) List assignment to %ENV is not supported on some systems, notably
1029VMS.
3e3baf6d 1030
cd40cd58
NC
1031=item Can't make loaded symbols global on this platform while loading %s
1032
ff9c1ae8 1033(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1034that symbols from the stated file are made available globally within the
1035process, but that functionality is not available on this platform. Whilst
1036the module likely will still work, this may prevent the perl interpreter
1037from loading other XS-based extensions which need to link directly to
1038functions defined in the C or XS code in the stated file.
1039
a0d0e21e
LW
1040=item Can't modify %s in %s
1041
be771a83
GS
1042(F) You aren't allowed to assign to the item indicated, or otherwise try
1043to change it, such as with an auto-increment.
a0d0e21e 1044
54310121 1045=item Can't modify nonexistent substring
a0d0e21e
LW
1046
1047(P) The internal routine that does assignment to a substr() was handed
1048a NULL.
1049
6df41af2
GS
1050=item Can't modify non-lvalue subroutine call
1051
1052(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1053such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1054
cf6e1fa1
FC
1055=item Can't modify reference to %s in %s assignment
1056
1057(F) Only a limited number of constructs can be used as the argument to a
1058reference constructor on the left-hand side of an assignment, and what
1059you used was not one of them. See L<perlref/Assigning to References>.
1060
1061=item Can't modify reference to localized parenthesized array in list
1062assignment
1063
1064(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1065it is not clear exactly what it should do. If you meant to make @array
1066refer to some other array, use C<\@array = \@other_array>. If you want to
1067make the elements of @array aliases of the scalars referenced on the
1068right-hand side, use C<\(@array) = @scalar_refs>.
1069
1070=item Can't modify reference to parenthesized hash in list assignment
1071
1072(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1073refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1074make the elements of %hash into aliases of the scalars referenced on the
1075right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1076
5f05dabc 1077=item Can't msgrcv to read-only var
a0d0e21e 1078
5f05dabc 1079(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1080buffer.
1081
6df41af2
GS
1082=item Can't "next" outside a loop block
1083
1084(F) A "next" statement was executed to reiterate the current block, but
1085there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1086count as a "loopish" block, as doesn't a block given to sort(), map() or
1087grep(). You can usually double the curlies to get the same effect
1088though, because the inner curlies will be considered a block that loops
1089once. See L<perlfunc/next>.
6df41af2 1090
a0d0e21e
LW
1091=item Can't open %s: %s
1092
c47ff5f1 1093(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1094filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1095switches, or explicitly, failed for the indicated reason. Usually
1096this is because you don't have read permission for a file which
1097you named on the command line.
1098
1099(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1100your operating system's equivalent) could not be opened.
a0d0e21e 1101
9a869a14
RGS
1102=item Can't open a reference
1103
1104(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1105using the 3-arg open() syntax:
9a869a14
RGS
1106
1107 open FH, '>', $ref;
1108
1109but your version of perl is compiled without perlio, and this form of
1110open is not supported.
1111
a0d0e21e
LW
1112=item Can't open bidirectional pipe
1113
be771a83
GS
1114(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1115You can try any of several modules in the Perl library to do this, such
1116as IPC::Open2. Alternately, direct the pipe's output to a file using
1117">", and then read it in under a different file handle.
a0d0e21e 1118
748a9306
LW
1119=item Can't open error file %s as stderr
1120
be771a83
GS
1121(F) An error peculiar to VMS. Perl does its own command line
1122redirection, and couldn't open the file specified after '2>' or '2>>' on
1123the command line for writing.
748a9306
LW
1124
1125=item Can't open input file %s as stdin
1126
be771a83
GS
1127(F) An error peculiar to VMS. Perl does its own command line
1128redirection, and couldn't open the file specified after '<' on the
1129command line for reading.
748a9306
LW
1130
1131=item Can't open output file %s as stdout
1132
be771a83
GS
1133(F) An error peculiar to VMS. Perl does its own command line
1134redirection, and couldn't open the file specified after '>' or '>>' on
1135the command line for writing.
748a9306
LW
1136
1137=item Can't open output pipe (name: %s)
1138
be771a83
GS
1139(P) An error peculiar to VMS. Perl does its own command line
1140redirection, and couldn't open the pipe into which to send data destined
1141for stdout.
748a9306 1142
3b1cf97d 1143=item Can't open perl script "%s": %s
a0d0e21e
LW
1144
1145(F) The script you specified can't be opened for the indicated reason.
1146
fa3aa65a
JC
1147If you're debugging a script that uses #!, and normally relies on the
1148shell's $PATH search, the -S option causes perl to do that search, so
1149you don't have to type the path or C<`which $scriptname`>.
1150
6df41af2
GS
1151=item Can't read CRTL environ
1152
1153(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1154from the CRTL's internal environment array and discovered the array was
1155missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1156or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1157searched.
6df41af2 1158
6df41af2
GS
1159=item Can't "redo" outside a loop block
1160
1161(F) A "redo" statement was executed to restart the current block, but
1162there isn't a current block. Note that an "if" or "else" block doesn't
1163count as a "loopish" block, as doesn't a block given to sort(), map()
1164or grep(). You can usually double the curlies to get the same effect
1165though, because the inner curlies will be considered a block that
1166loops once. See L<perlfunc/redo>.
1167
64977eb6 1168=item Can't remove %s: %s, skipping file
10f9c03d 1169
be771a83
GS
1170(S inplace) You requested an inplace edit without creating a backup
1171file. Perl was unable to remove the original file to replace it with
1172the modified file. The file was left unmodified.
10f9c03d 1173
a0d0e21e
LW
1174=item Can't rename %s to %s: %s, skipping file
1175
e476b1b5 1176(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1177probably because you don't have write permission to the directory.
a0d0e21e 1178
748a9306
LW
1179=item Can't reopen input pipe (name: %s) in binary mode
1180
be771a83
GS
1181(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1182to reopen it to accept binary data. Alas, it failed.
748a9306 1183
4f12ec0e
FC
1184=item Can't reset %ENV on this system
1185
1186(F) You called C<reset('E')> or similar, which tried to reset
1187all variables in the current package beginning with "E". In
1188the main package, that includes %ENV. Resetting %ENV is not
1189supported on some systems, notably VMS.
1190
fe13d51d 1191=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1192
1fa582fa
FC
1193(F)(P) Error resolving overloading specified by a method name (as
1194opposed to a subroutine reference): no such method callable via the
1195package. If the method name is C<???>, this is an internal error.
6df41af2 1196
cd06dffe
GS
1197=item Can't return %s from lvalue subroutine
1198
be771a83
GS
1199(F) Perl detected an attempt to return illegal lvalues (such as
1200temporary or readonly values) from a subroutine used as an lvalue. This
1201is not allowed.
cd06dffe 1202
96ebfdd7
RK
1203=item Can't return outside a subroutine
1204
1205(F) The return statement was executed in mainline code, that is, where
1206there was no subroutine call to return out of. See L<perlsub>.
1207
78f9721b
SM
1208=item Can't return %s to lvalue scalar context
1209
6903afa2
FC
1210(F) You tried to return a complete array or hash from an lvalue
1211subroutine, but you called the subroutine in a way that made Perl
1212think you meant to return only one value. You probably meant to
1213write parentheses around the call to the subroutine, which tell
1214Perl that the call should be in list context.
78f9721b 1215
a0d0e21e
LW
1216=item Can't stat script "%s"
1217
be771a83
GS
1218(P) For some reason you can't fstat() the script even though you have it
1219open already. Bizarre.
a0d0e21e 1220
a0d0e21e
LW
1221=item Can't take log of %g
1222
fb73857a 1223(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1224negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1225standard with Perl, though, if you really want to do that for the
1226negative numbers.
a0d0e21e
LW
1227
1228=item Can't take sqrt of %g
1229
1230(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1231negative number. There's a Math::Complex package that comes standard
1232with Perl, though, if you really want to do that.
a0d0e21e
LW
1233
1234=item Can't undef active subroutine
1235
1236(F) You can't undefine a routine that's currently running. You can,
1237however, redefine it while it's running, and you can even undef the
1238redefined subroutine while the old routine is running. Go figure.
1239
c81225bc 1240=item Can't upgrade %s (%d) to %d
a0d0e21e 1241
be771a83
GS
1242(P) The internal sv_upgrade routine adds "members" to an SV, making it
1243into a more specialized kind of SV. The top several SV types are so
1244specialized, however, that they cannot be interconverted. This message
1245indicates that such a conversion was attempted.
a0d0e21e 1246
6651ba0b
FC
1247=item Can't use '%c' after -mname
1248
1249(F) You tried to call perl with the B<-m> switch, but you put something
1250other than "=" after the module name.
1251
1f1ec7b5
KW
1252=item Can't use a hash as a reference
1253
1254(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1255C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1256<= 5.22.0 used to allow this syntax, but shouldn't
1257have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1258
1259=item Can't use an array as a reference
1260
1261(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1262C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1263used to allow this syntax, but shouldn't have. This
1264was deprecated in perl 5.6.1.
1f1ec7b5 1265
1db89ea5
BS
1266=item Can't use anonymous symbol table for method lookup
1267
e27ad1f2 1268(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1269table that doesn't have a name. Symbol tables can become anonymous
1270for example by undefining stashes: C<undef %Some::Package::>.
1271
96ebfdd7
RK
1272=item Can't use an undefined value as %s reference
1273
1274(F) A value used as either a hard reference or a symbolic reference must
1275be a defined value. This helps to delurk some insidious errors.
1276
6df41af2
GS
1277=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1278
be771a83
GS
1279(F) Only hard references are allowed by "strict refs". Symbolic
1280references are disallowed. See L<perlref>.
6df41af2 1281
90b75b61 1282=item Can't use %! because Errno.pm is not available
1d2dff63 1283
20561843 1284(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1285Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1286provide symbolic names for C<$!> errno values.
1287
1109a392
MHM
1288=item Can't use both '<' and '>' after type '%c' in %s
1289
1290(F) A type cannot be forced to have both big-endian and little-endian
1291byte-order at the same time, so this combination of modifiers is not
1292allowed. See L<perlfunc/pack>.
1293
e35475de
KW
1294=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1295
1296(F) defined() is not useful on arrays because it
1297checks for an undefined I<scalar> value. If you want to see if the
1298array is empty, just use C<if (@array) { # not empty }> for example.
1299
1300=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1301
1302(F) C<defined()> is not usually right on hashes.
1303
1304Although C<defined %hash> is false on a plain not-yet-used hash, it
1305becomes true in several non-obvious circumstances, including iterators,
1306weak references, stash names, even remaining true after C<undef %hash>.
1307These things make C<defined %hash> fairly useless in practice, so it now
1308generates a fatal error.
1309
1310If a check for non-empty is what you wanted then just put it in boolean
1311context (see L<perldata/Scalar values>):
1312
1313 if (%hash) {
1314 # not empty
1315 }
1316
1317If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1318variable exists then that's never really been reliable, and isn't
1319a good way to enquire about the features of a package, or whether
1320it's loaded, etc.
1321
6df41af2
GS
1322=item Can't use %s for loop variable
1323
be771a83
GS
1324(F) Only a simple scalar variable may be used as a loop variable on a
1325foreach.
6df41af2 1326
aab6a793 1327=item Can't use global %s in "%s"
6df41af2 1328
be771a83
GS
1329(F) You tried to declare a magical variable as a lexical variable. This
1330is not allowed, because the magic can be tied to only one location
1331(namely the global variable) and it would be incredibly confusing to
1332have variables in your program that looked like magical variables but
6df41af2
GS
1333weren't.
1334
6d3b25aa
RGS
1335=item Can't use '%c' in a group with different byte-order in %s
1336
1337(F) You attempted to force a different byte-order on a type
1338that is already inside a group with a byte-order modifier.
1339For example you cannot force little-endianness on a type that
1340is inside a big-endian group.
1341
c07a80fd
PP
1342=item Can't use "my %s" in sort comparison
1343
1344(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1345You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1346and the variable had earlier been declared as a lexical variable.
1347Either qualify the sort variable with the package name, or rename the
1348lexical variable.
1349
a0d0e21e
LW
1350=item Can't use %s ref as %s ref
1351
1352(F) You've mixed up your reference types. You have to dereference a
1353reference of the type needed. You can use the ref() function to
1354test the type of the reference, if need be.
1355
748a9306 1356=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1357
5e634d20
FC
1358=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1359
b41bf23f
FC
1360(F) You've told Perl to dereference a string, something which
1361C<use strict> blocks to prevent it happening accidentally. See
1362L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1363in a double-quoted string immediately before interpolating a variable,
1364for example in C<"user @$twitter_id">, which says to treat the contents
1365of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1366symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1367
748a9306
LW
1368=item Can't use subscript on %s
1369
1370(F) The compiler tried to interpret a bracketed expression as a
1371subscript. But to the left of the brackets was an expression that
209e7cf1 1372didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1373
6df41af2
GS
1374=item Can't use \%c to mean $%c in expression
1375
75b44862
GS
1376(W syntax) In an ordinary expression, backslash is a unary operator that
1377creates a reference to its argument. The use of backslash to indicate a
1378backreference to a matched substring is valid only as part of a regular
be771a83
GS
1379expression pattern. Trying to do this in ordinary Perl code produces a
1380value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1381instead.
6df41af2 1382
810b8aa5
GS
1383=item Can't weaken a nonreference
1384
1385(F) You attempted to weaken something that was not a reference. Only
1386references can be weakened.
1387
fc7debfb
FC
1388=item Can't "when" outside a topicalizer
1389
1390(F) You have used a when() block that is neither inside a C<foreach>
1391loop nor a C<given> block. (Note that this error is issued on exit
1392from the C<when> block, so you won't get the error if the match fails,
1393or if you use an explicit C<continue>.)
1394
5f05dabc 1395=item Can't x= to read-only value
a0d0e21e 1396
be771a83
GS
1397(F) You tried to repeat a constant value (often the undefined value)
1398with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1399Perhaps you need to copy the value to a temporary, and repeat that.
1400
a04e6aad 1401=item Character following "\c" must be printable ASCII
f9d13529 1402
7357bd17 1403(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1404
727b6379 1405Note that ASCII characters that don't map to control characters are
7357bd17 1406discouraged, and will generate the warning (when enabled)
727b6379 1407L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1408
f337b084 1409=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1410
1411(W pack) You said
1412
1413 pack("C", $x)
1414
1415where $x is either less than 0 or more than 255; the C<"C"> format is
1416only for encoding native operating system characters (ASCII, EBCDIC,
1417and so on) and not for Unicode characters, so Perl behaved as if you meant
1418
1419 pack("C", $x & 255)
1420
1421If you actually want to pack Unicode codepoints, use the C<"U"> format
1422instead.
1423
f337b084 1424=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1425
1426(W pack) You said
1427
1428 pack("c", $x)
1429
1430where $x is either less than -128 or more than 127; the C<"c"> format
1431is only for encoding native operating system characters (ASCII, EBCDIC,
1432and so on) and not for Unicode characters, so Perl behaved as if you meant
1433
1434 pack("c", $x & 255);
1435
1436If you actually want to pack Unicode codepoints, use the C<"U"> format
1437instead.
1438
f337b084
TH
1439=item Character in '%c' format wrapped in unpack
1440
1441(W unpack) You tried something like
1442
1443 unpack("H", "\x{2a1}")
1444
1a147d38 1445where the format expects to process a byte (a character with a value
6903afa2
FC
1446below 256), but a higher value was provided instead. Perl uses the
1447value modulus 256 instead, as if you had provided:
f337b084
TH
1448
1449 unpack("H", "\x{a1}")
1450
5a25739d
FC
1451=item Character in 'W' format wrapped in pack
1452
1453(W pack) You said
1454
1455 pack("U0W", $x)
1456
1457where $x is either less than 0 or more than 255. However, C<U0>-mode
1458expects all values to fall in the interval [0, 255], so Perl behaved
1459as if you meant:
1460
1461 pack("U0W", $x & 255)
1462
f337b084
TH
1463=item Character(s) in '%c' format wrapped in pack
1464
1465(W pack) You tried something like
1466
1467 pack("u", "\x{1f3}b")
1468
1a147d38 1469where the format expects to process a sequence of bytes (character with a
6903afa2 1470value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1471uses the character values modulus 256 instead, as if you had provided:
1472
1473 pack("u", "\x{f3}b")
1474
1475=item Character(s) in '%c' format wrapped in unpack
1476
1477(W unpack) You tried something like
1478
1479 unpack("s", "\x{1f3}b")
1480
1a147d38 1481where the format expects to process a sequence of bytes (character with a
6903afa2 1482value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1483uses the character values modulus 256 instead, as if you had provided:
1484
1485 unpack("s", "\x{f3}b")
1486
f51551f7
FC
1487=item charnames alias definitions may not contain a sequence of multiple spaces
1488
1489(F) You defined a character name which had multiple space characters
1490in a row. Change them to single spaces. Usually these names are
1491defined in the C<:alias> import argument to C<use charnames>, but they
1492could be defined by a translator installed into C<$^H{charnames}>. See
1493L<charnames/CUSTOM ALIASES>.
1494
1495=item charnames alias definitions may not contain trailing white-space
1496
1497(F) You defined a character name which ended in a space
1498character. Remove the trailing space(s). Usually these names are
1499defined in the C<:alias> import argument to C<use charnames>, but they
1500could be defined by a translator installed into C<$^H{charnames}>.
1501See L<charnames/CUSTOM ALIASES>.
1502
1503=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1504
1505(D deprecated, regexp) The \C character class is deprecated, and will
1506become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1507v5.24). This construct allows you to match a single byte of what makes
1508up a multi-byte single UTF8 character, and breaks encapsulation. It is
1509currently also very buggy. If you really need to process the individual
f51551f7
FC
1510bytes, you probably want to convert your string to one where each
1511underlying byte is stored as a character, with utf8::encode().
1512
f866a7cd
FC
1513=item "\c%c" is more clearly written simply as "%s"
1514
1515(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1516non-printable characters. You used it for a printable one, which
1517is better written as simply itself, perhaps preceded by a backslash
1518for non-word characters. Doing it the way you did is not portable
1519between ASCII and EBCDIC platforms.
f866a7cd 1520
6651ba0b
FC
1521=item Cloning substitution context is unimplemented
1522
1523(F) Creating a new thread inside the C<s///> operator is not supported.
1524
abc7ecad
SP
1525=item closedir() attempted on invalid dirhandle %s
1526
1527(W io) The dirhandle you tried to close is either closed or not really
1528a dirhandle. Check your control flow.
1529
5a25739d
FC
1530=item close() on unopened filehandle %s
1531
1532(W unopened) You tried to close a filehandle that was never opened.
1533
541ed3a9
FC
1534=item Closure prototype called
1535
1536(F) If a closure has attributes, the subroutine passed to an attribute
1537handler is the prototype that is cloned when a new closure is created.
1538This subroutine cannot be called.
1539
49704364
LW
1540=item Code missing after '/'
1541
6903afa2
FC
1542(F) You had a (sub-)template that ends with a '/'. There must be
1543another template code following the slash. See L<perlfunc/pack>.
49704364 1544
5a25739d
FC
1545=item Code point 0x%X is not Unicode, may not be portable
1546
2d88a86a 1547(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1548of U+10FFFF.
1549
1550Perl allows strings to contain a superset of Unicode code points, up
1551to the limit of what is storable in an unsigned integer on your system,
1552but these may not be accepted by other languages/systems. At one time,
1553it was legal in some standards to have code points up to 0x7FFF_FFFF,
1554but not higher. Code points above 0xFFFF_FFFF require larger than a
155532 bit word.
0876b9a0 1556
6df41af2
GS
1557=item %s: Command not found
1558
a892b81a 1559(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1560instead of Perl. Check the #! line, or manually feed your script into
1561Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1562
1563 #!/usr/bin/perl -w
6df41af2 1564
7a2e2cd6
PP
1565=item Compilation failed in require
1566
1567(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1568Perl uses this generic message when none of the errors that it
1569encountered were severe enough to halt compilation immediately.
7a2e2cd6 1570
c3464db5
DD
1571=item Complex regular subexpression recursion limit (%d) exceeded
1572
be771a83
GS
1573(W regexp) The regular expression engine uses recursion in complex
1574situations where back-tracking is required. Recursion depth is limited
1575to 32766, or perhaps less in architectures where the stack cannot grow
1576arbitrarily. ("Simple" and "medium" situations are handled without
1577recursion and are not subject to a limit.) Try shortening the string
1578under examination; looping in Perl code (e.g. with C<while>) rather than
1579in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1580that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1581on I<Mastering Regular Expressions>.)
c3464db5 1582
69282e91 1583=item connect() on closed socket %s
a0d0e21e 1584
be771a83
GS
1585(W closed) You tried to do a connect on a closed socket. Did you forget
1586to check the return value of your socket() call? See
1587L<perlfunc/connect>.
a0d0e21e 1588
e21e7c6a
FC
1589=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1590
1591(F) The subroutine registered to handle constant overloading
1592(see L<overload>) or a custom charnames handler (see
1593L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1594
1595=item Constant(%s): $^H{%s} is not defined
1596
1597(F) The parser found inconsistencies while attempting to define an
1598overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1599L<overload> pragma?
e21e7c6a 1600
779c5bc9
GS
1601=item Constant is not %s reference
1602
1603(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1604is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1605The message indicates the type of reference that was expected. This
be771a83 1606usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1607See L<perlsub/"Constant Functions"> and L<constant>.
1608
4cee8e80
CS
1609=item Constant subroutine %s redefined
1610
aeb94125
FC
1611(W redefine)(S) You redefined a subroutine which had previously
1612been eligible for inlining. See L<perlsub/"Constant Functions">
1613for commentary and workarounds.
4cee8e80 1614
9607fc9c
PP
1615=item Constant subroutine %s undefined
1616
be771a83
GS
1617(W misc) You undefined a subroutine which had previously been eligible
1618for inlining. See L<perlsub/"Constant Functions"> for commentary and
1619workarounds.
9607fc9c 1620
5a25739d
FC
1621=item Constant(%s) unknown
1622
1623(F) The parser found inconsistencies either while attempting
1624to define an overloaded constant, or when trying to find the
1625character name specified in the C<\N{...}> escape. Perhaps you
1626forgot to load the corresponding L<overload> pragma?.
1627
e7ea3e70
IZ
1628=item Copy method did not return a reference
1629
6903afa2 1630(F) The method which overloads "=" is buggy. See
13a2d996 1631L<overload/Copy Constructor>.
e7ea3e70 1632
4aaa4757
FC
1633=item &CORE::%s cannot be called directly
1634
1635(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1636with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1637in this package cannot yet be called that way, but must be
1638called as barewords. Something like this will work:
1639
1640 BEGIN { *shove = \&CORE::push; }
1641 shove @array, 1,2,3; # pushes on to @array
1642
6798c92b
GS
1643=item CORE::%s is not a keyword
1644
1645(F) The CORE:: namespace is reserved for Perl keywords.
1646
675fa9ff
FC
1647=item Corrupted regexp opcode %d > %d
1648
1649(P) This is either an error in Perl, or, if you're using
1650one, your L<custom regular expression engine|perlreapi>. If not the
1651latter, report the problem through the L<perlbug> utility.
1652
a0d0e21e
LW
1653=item corrupted regexp pointers
1654
1655(P) The regular expression engine got confused by what the regular
1656expression compiler gave it.
1657
1658=item corrupted regexp program
1659
be771a83
GS
1660(P) The regular expression engine got passed a regexp program without a
1661valid magic number.
a0d0e21e 1662
de42a5a9 1663=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1664
1665(P) The malloc package that comes with Perl had an internal failure.
1666
49704364
LW
1667=item Count after length/code in unpack
1668
1669(F) You had an unpack template indicating a counted-length string, but
1670you have also specified an explicit size for the string. See
1671L<perlfunc/pack>.
1672
f2cccb4c
KW
1673=for comment
1674The following are used in lib/diagnostics.t for testing two =items that
1675share the same description. Changes here need to be propagated to there
1676
6651ba0b
FC
1677=item Deep recursion on anonymous subroutine
1678
a0d0e21e
LW
1679=item Deep recursion on subroutine "%s"
1680
be771a83
GS
1681(W recursion) This subroutine has called itself (directly or indirectly)
1682100 times more than it has returned. This probably indicates an
1683infinite recursion, unless you're writing strange benchmark programs, in
1684which case it indicates something else.
a0d0e21e 1685
aad1d01f
NC
1686This threshold can be changed from 100, by recompiling the F<perl> binary,
1687setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1688
e0e4a6e3
FC
1689=item (?(DEFINE)....) does not allow branches in regex; marked by
1690S<<-- HERE> in m/%s/
bcb95744 1691
6903afa2 1692(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1693most likely cause of this error is that you left out a parenthesis inside
1694of the C<....> part.
1695
9e3ec65c 1696The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1697discovered.
1698
62658f4d
PM
1699=item %s defines neither package nor VERSION--version check failed
1700
1701(F) You said something like "use Module 42" but in the Module file
1702there are neither package declarations nor a C<$VERSION>.
1703
36447869
FC
1704=item delete argument is index/value array slice, use array slice
1705
1706(F) You used index/value array slice syntax (C<%array[...]>) as
1707the argument to C<delete>. You probably meant C<@array[...]> with
1708an @ symbol instead.
1709
1710=item delete argument is key/value hash slice, use hash slice
1711
1712(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1713C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1714
0ffcbc25
FC
1715=item delete argument is not a HASH or ARRAY element or slice
1716
4a0af295 1717(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1718such as:
1719
1720 $foo{$bar}
1721 $ref->{"susie"}[12]
1722
1723or a hash or array slice, such as:
1724
1725 @foo[$bar, $baz, $xyzzy]
1726 @{$ref->[12]}{"susie", "queue"}
1727
fc36a67e
PP
1728=item Delimiter for here document is too long
1729
be771a83
GS
1730(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1731long for Perl to handle. You have to be seriously twisted to write code
1732that triggers this error.
fc36a67e 1733
6d3b25aa
RGS
1734=item Deprecated use of my() in false conditional
1735
fa816bf3
FC
1736(D deprecated) You used a declaration similar to C<my $x if 0>. There
1737has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1738not to be cleared at scope exit when its declaration includes a false
6903afa2 1739conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1740static variable. Since we intend to fix this bug, we don't want people
6903afa2 1741relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1742declaring the variable in a separate block outside the function, eg
36fb85f3 1743
6d3b25aa
RGS
1744 sub f { my $x if 0; return $x++ }
1745
1746becomes
1747
1748 { my $x; sub f { return $x++ } }
1749
ea9d9ebc 1750Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1751lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1752
1753 sub f { state $x; return $x++ }
1754
500ab966
RGS
1755=item DESTROY created new reference to dead object '%s'
1756
1757(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1758just being DESTROYed. Perl is confused, and prefers to abort rather
1759than to create a dangling reference.
500ab966 1760
3cdd684c
TP
1761=item Did not produce a valid header
1762
1763See Server error.
1764
6df41af2
GS
1765=item %s did not return a true value
1766
1767(F) A required (or used) file must return a true value to indicate that
1768it compiled correctly and ran its initialization code correctly. It's
1769traditional to end such a file with a "1;", though any true value would
1770do. See L<perlfunc/require>.
1771
cc507455 1772=item (Did you mean &%s instead?)
4633a7c4 1773
413ff9f6
FC
1774(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1775some such.
4633a7c4 1776
cc507455 1777=item (Did you mean "local" instead of "our"?)
33633739 1778
be771a83
GS
1779(W misc) Remember that "our" does not localize the declared global
1780variable. You have declared it again in the same lexical scope, which
1781seems superfluous.
33633739 1782
cc507455 1783=item (Did you mean $ or @ instead of %?)
a0d0e21e 1784
be771a83
GS
1785(W) You probably said %hash{$key} when you meant $hash{$key} or
1786@hash{@keys}. On the other hand, maybe you just meant %hash and got
1787carried away.
748a9306 1788
7e1af8bc 1789=item Died
5f05dabc
PP
1790
1791(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1792you called it with no args and C<$@> was empty.
5f05dabc 1793
3cdd684c
TP
1794=item Document contains no data
1795
1796See Server error.
1797
62658f4d
PM
1798=item %s does not define %s::VERSION--version check failed
1799
1800(F) You said something like "use Module 42" but the Module did not
943fc58e 1801define a C<$VERSION>.
62658f4d 1802
49704364
LW
1803=item '/' does not take a repeat count
1804
1805(F) You cannot put a repeat count of any kind right after the '/' code.
1806See L<perlfunc/pack>.
1807
95cb0d72
FC
1808=item Don't know how to get file name
1809
1810(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1811somehow called on another platform. This should not happen.
1812
4021c788 1813=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1814
1815(P) The internal handling of magical variables has been cursed.
1816
1817=item do_study: out of memory
1818
1819(P) This should have been caught by safemalloc() instead.
1820
6df41af2
GS
1821=item (Do you need to predeclare %s?)
1822
56da5a46
RGS
1823(S syntax) This is an educated guess made in conjunction with the message
1824"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1825name is being referenced that hasn't been declared yet. This may be
1826because of ordering problems in your file, or because of a missing
be771a83
GS
1827"sub", "package", "require", or "use" statement. If you're referencing
1828something that isn't defined yet, you don't actually have to define the
1829subroutine or package before the current location. You can use an empty
1830"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1831
ac206dc8
RGS
1832=item dump() better written as CORE::dump()
1833
1834(W misc) You used the obsolescent C<dump()> built-in function, without fully
1835qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1836
84d78eb7
YO
1837=item dump is not supported
1838
1839(F) Your machine doesn't support dump/undump.
1840
a0d0e21e
LW
1841=item Duplicate free() ignored
1842
be771a83
GS
1843(S malloc) An internal routine called free() on something that had
1844already been freed.
a0d0e21e 1845
1109a392
MHM
1846=item Duplicate modifier '%c' after '%c' in %s
1847
35f0cd76
FC
1848(W unpack) You have applied the same modifier more than once after a
1849type in a pack template. See L<perlfunc/pack>.
1109a392 1850
0953b66b
FC
1851=item each on reference is experimental
1852
0773cb3e
FC
1853(S experimental::autoderef) C<each> with a scalar argument is experimental
1854and may change or be removed in a future Perl version. If you want to
1855take the risk of using this feature, simply disable this warning:
0953b66b 1856
d401967c 1857 no warnings "experimental::autoderef";
0953b66b 1858
4633a7c4
LW
1859=item elseif should be elsif
1860
fa816bf3
FC
1861(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1862it's ugly. Your code will be interpreted as an attempt to call a method
1863named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1864unlikely to be what you want.
1865
e0e4a6e3 1866=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1867
af6f566e 1868(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1869described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1870a regular expression without specifying the property name.
ab13f0c7 1871
85ab1d1d 1872=item entering effective %s failed
5ff3f7a4 1873
85ab1d1d 1874(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1875effective uids or gids failed.
1876
c038024b
RGS
1877=item %ENV is aliased to %s
1878
1879(F) You're running under taint mode, and the C<%ENV> variable has been
1880aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1881program's environment. This is potentially insecure.
c038024b 1882
748a9306
LW
1883=item Error converting file specification %s
1884
5f05dabc 1885(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1886specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1887single form when it must operate on them directly. Either you've passed
1888an invalid file specification to Perl, or you've found a case the
1889conversion routines don't handle. Drat.
748a9306 1890
ad19ef22 1891=item Eval-group in insecure regular expression
e4d48cc9 1892
be771a83
GS
1893(F) Perl detected tainted data when trying to compile a regular
1894expression that contains the C<(?{ ... })> zero-width assertion, which
1895is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1896
ad19ef22 1897=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1898
be771a83
GS
1899(F) Perl tried to compile a regular expression containing the
1900C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1901pattern contains interpolated values. Since that is a security risk,
1902it is not allowed. If you insist, you may still do this by using the
1903C<re 'eval'> pragma or by explicitly building the pattern from an
1904interpolated string at run time and using that in an eval(). See
1905L<perlre/(?{ code })>.
e4d48cc9 1906
ad19ef22 1907=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1908
be771a83
GS
1909(F) A regular expression contained the C<(?{ ... })> zero-width
1910assertion, but that construct is only allowed when the C<use re 'eval'>
1911pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1912
e0e4a6e3
FC
1913=item EVAL without pos change exceeded limit in regex; marked by
1914S<<-- HERE> in m/%s/
1a147d38
YO
1915
1916(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1917any text. Restructure the pattern so that text is consumed.
1a147d38 1918
9e3ec65c 1919The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1920discovered.
1921
fc36a67e
PP
1922=item Excessively long <> operator
1923
1924(F) The contents of a <> operator may not exceed the maximum size of a
1925Perl identifier. If you're just trying to glob a long list of
1926filenames, try using the glob() operator, or put the filenames into a
1927variable and glob that.
1928
ed9aa3b7
SG
1929=item exec? I'm not *that* kind of operating system
1930
af8bb25a 1931(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1932OS. See L<perlport>.
ed9aa3b7 1933
fe13d51d 1934=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1935
1936(F) The final summary message when a Perl compilation fails.
1937
0ffcbc25
FC
1938=item exists argument is not a HASH or ARRAY element or a subroutine
1939
4a0af295 1940(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1941subroutine with an ampersand, such as:
1942
1943 $foo{$bar}
1944 $ref->{"susie"}[12]
1945 &do_something
1946
1947=item exists argument is not a subroutine name
1948
ccfc2567
FC
1949(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1950and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1951
a0d0e21e
LW
1952=item Exiting eval via %s
1953
be771a83
GS
1954(W exiting) You are exiting an eval by unconventional means, such as a
1955goto, or a loop control statement.
e476b1b5
GS
1956
1957=item Exiting format via %s
1958
9a2ff54b 1959(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1960goto, or a loop control statement.
a0d0e21e 1961
0a753a76
PP
1962=item Exiting pseudo-block via %s
1963
be771a83
GS
1964(W exiting) You are exiting a rather special block construct (like a
1965sort block or subroutine) by unconventional means, such as a goto, or a
1966loop control statement. See L<perlfunc/sort>.
0a753a76 1967
a0d0e21e
LW
1968=item Exiting subroutine via %s
1969
be771a83
GS
1970(W exiting) You are exiting a subroutine by unconventional means, such
1971as a goto, or a loop control statement.
a0d0e21e
LW
1972
1973=item Exiting substitution via %s
1974
be771a83
GS
1975(W exiting) You are exiting a substitution by unconventional means, such
1976as a return, a goto, or a loop control statement.
a0d0e21e 1977
e0e4a6e3 1978=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1979
675fa9ff 1980(F) You wrote something like
c608e803
KW
1981
1982 (?13
1983
1984to denote a capturing group of the form
1985L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1986but omitted the C<")">.
1987
e0e4a6e3 1988=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1989
8b6fbf55
FC
1990(F) The C<(?[...])> extended character class regular expression construct
1991only allows character classes (including character class escapes like
1992C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1993containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1994This allows a regular expression containing just C<(?[...])> to be
1995interpolated. If you see this error message, then you probably
1996have some other C<(?...)> construct inside your character class. See
1997L<perlrecharclass/Extended Bracketed Character Classes>.
1998
baabe3fb 1999=item Experimental aliasing via reference not enabled
1f8155a2 2000
baabe3fb 2001(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2002
baabe3fb
FC
2003 no warnings "experimental::refaliasing";
2004 use feature "refaliasing";
1f8155a2
FC
2005 \$x = \$y;
2006
30d9c59b
Z
2007=item Experimental subroutine signatures not enabled
2008
2009(F) To use subroutine signatures, you must first enable them:
2010
caa35032 2011 no warnings "experimental::signatures";
30d9c59b
Z
2012 use feature "signatures";
2013 sub foo ($left, $right) { ... }
2014
6da34ecb
FC
2015=item Experimental "%s" subs not enabled
2016
2017(F) To use lexical subs, you must first enable them:
2018
2019 no warnings 'experimental::lexical_subs';
2020 use feature 'lexical_subs';
2021 my sub foo { ... }
2022
7b8d334a
GS
2023=item Explicit blessing to '' (assuming package main)
2024
be771a83
GS
2025(W misc) You are blessing a reference to a zero length string. This has
2026the effect of blessing the reference into the package main. This is
2027usually not what you want. Consider providing a default target package,
2028e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2029
6df41af2
GS
2030=item %s: Expression syntax
2031
be771a83
GS
2032(A) You've accidentally run your script through B<csh> instead of Perl.
2033Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2034
2035=item %s failed--call queue aborted
2036
3c10abe3
AG
2037(F) An untrapped exception was raised while executing a UNITCHECK,
2038CHECK, INIT, or END subroutine. Processing of the remainder of the
2039queue of such routines has been prematurely ended.
6df41af2 2040
e0e4a6e3 2041=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2042
98d31c73 2043(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2044character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2045in your false range is interpreted as a literal "-". In a C<(?[...])>
2046construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2047the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2048the problem was discovered. See L<perlre>.
73b437c8 2049
1b1ee2ef 2050=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2051
be771a83
GS
2052(P) An error peculiar to VMS. Something untoward happened in a VMS
2053system service or RTL routine; Perl's exit status should provide more
2054details. The filename in "at %s" and the line number in "line %d" tell
2055you which section of the Perl source code is distressed.
a0d0e21e
LW
2056
2057=item fcntl is not implemented
2058
2059(F) Your machine apparently doesn't implement fcntl(). What is this, a
2060PDP-11 or something?
2061
22846ab4
AB
2062=item FETCHSIZE returned a negative value
2063
2064(F) A tied array claimed to have a negative number of elements, which
2065is not possible.
2066
f337b084
TH
2067=item Field too wide in 'u' format in pack
2068
d8b5cc61 2069(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2070which can't encode values above 63. So there is no point in asking for
2071a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2072C<u63> as the format.
f337b084 2073
af8c498a 2074=item Filehandle %s opened only for input
a0d0e21e 2075
6c8d78fb
HS
2076(W io) You tried to write on a read-only filehandle. If you intended
2077it to be a read-write filehandle, you needed to open it with "+<" or
2078"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2079write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2080
af8c498a 2081=item Filehandle %s opened only for output
a0d0e21e 2082
6c8d78fb
HS
2083(W io) You tried to read from a filehandle opened only for writing, If
2084you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2085with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2086read from the file, use "<". See L<perlfunc/open>. Another possibility
2087is that you attempted to open filedescriptor 0 (also known as STDIN) for
2088output (maybe you closed STDIN earlier?).
97828cef
RGS
2089
2090=item Filehandle %s reopened as %s only for input
2091
2092(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2093as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2094previously.
2095
2096=item Filehandle STDIN reopened as %s only for output
2097
2098(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2099as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2100
2101=item Final $ should be \$ or $name
2102
2103(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2104a literal dollar sign, or was meant to introduce a variable name that
2105happens to be missing. So you have to put either the backslash or the
2106name.
a0d0e21e 2107
56e90b21
GS
2108=item flock() on closed filehandle %s
2109
be771a83 2110(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2111some time before now. Check your control flow. flock() operates on
be771a83
GS
2112filehandles. Are you attempting to call flock() on a dirhandle by the
2113same name?
56e90b21 2114
6df41af2
GS
2115=item Format not terminated
2116
2117(F) A format must be terminated by a line with a solitary dot. Perl got
2118to the end of your file without finding such a line.
2119
a0d0e21e
LW
2120=item Format %s redefined
2121
e476b1b5 2122(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2123
2124 {
271595cc 2125 no warnings 'redefine';
a0d0e21e
LW
2126 eval "format NAME =...";
2127 }
2128
a0d0e21e
LW
2129=item Found = in conditional, should be ==
2130
e476b1b5 2131(W syntax) You said
a0d0e21e
LW
2132
2133 if ($foo = 123)
2134
2135when you meant
2136
2137 if ($foo == 123)
2138
2139(or something like that).
2140
6df41af2
GS
2141=item %s found where operator expected
2142
56da5a46
RGS
2143(S syntax) The Perl lexer knows whether to expect a term or an operator.
2144If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2145operator, it gives you this warning. Usually it indicates that an
2146operator or delimiter was omitted, such as a semicolon.
6df41af2 2147
a0d0e21e
LW
2148=item gdbm store returned %d, errno %d, key "%s"
2149
2150(S) A warning from the GDBM_File extension that a store failed.
2151
2152=item gethostent not implemented
2153
2154(F) Your C library apparently doesn't implement gethostent(), probably
2155because if it did, it'd feel morally obligated to return every hostname
2156on the Internet.
2157
69282e91 2158=item get%sname() on closed socket %s
a0d0e21e 2159
be771a83
GS
2160(W closed) You tried to get a socket or peer socket name on a closed
2161socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2162
748a9306
LW
2163=item getpwnam returned invalid UIC %#o for user "%s"
2164
2165(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2166C<getpwnam> operator returned an invalid UIC.
2167
6df41af2
GS
2168=item getsockopt() on closed socket %s
2169
be771a83
GS
2170(W closed) You tried to get a socket option on a closed socket. Did you
2171forget to check the return value of your socket() call? See
6df41af2
GS
2172L<perlfunc/getsockopt>.
2173
0f539b13
BF
2174=item given is experimental
2175
675fa9ff
FC
2176(S experimental::smartmatch) C<given> depends on smartmatch, which
2177is experimental, so its behavior may change or even be removed
2178in any future release of perl. See the explanation under
2179L<perlsyn/Experimental Details on given and when>.
0f539b13 2180
68567d27
FC
2181=item Global symbol "%s" requires explicit package name (did you forget to
2182declare "my %s"?)
6df41af2 2183
a4edf47d 2184(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2185that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2186declared beforehand using "our", or explicitly qualified to say
2187which package the global variable is in (using "::").
6df41af2 2188
e476b1b5
GS
2189=item glob failed (%s)
2190
5ead438e 2191(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2192for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2193pattern that caused the external program to fail and exit with a
be771a83 2194nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2195resulted in a coredump, this may also mean that your csh (C shell)
2196is broken. If so, you should change all of the csh-related variables
2197in config.sh: If you have tcsh, make the variables refer to it as
2198if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2199all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2200think csh is missing. In either case, after editing config.sh, run
75b44862 2201C<./Configure -S> and rebuild Perl.
e476b1b5 2202
a0d0e21e
LW
2203=item Glob not terminated
2204
2205(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2206a term, so it's looking for the corresponding right angle bracket, and
2207not finding it. Chances are you left some needed parentheses out
2208earlier in the line, and you really meant a "less than".
a0d0e21e 2209
b35b96b6
JH
2210=item gmtime(%f) failed
2211
2212(W overflow) You called C<gmtime> with a number that it could not handle:
2213too large, too small, or NaN. The returned value is C<undef>.
2214
bcd05b94 2215=item gmtime(%f) too large
8b56d6ff 2216
e9200be3 2217(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2218it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2219date. This warning is also triggered with NaN (the special
fc003d4b
MS
2220not-a-number value).
2221
bcd05b94 2222=item gmtime(%f) too small
fc003d4b 2223
e9200be3 2224(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2225it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2226
6df41af2 2227=item Got an error from DosAllocMem
a0d0e21e 2228
6df41af2
GS
2229(P) An error peculiar to OS/2. Most probably you're using an obsolete
2230version of Perl, and this should not happen anyway.
a0d0e21e
LW
2231
2232=item goto must have label
2233
2234(F) Unlike with "next" or "last", you're not allowed to goto an
2235unspecified destination. See L<perlfunc/goto>.
2236
6651ba0b
FC
2237=item Goto undefined subroutine%s
2238
2239(F) You tried to call a subroutine with C<goto &sub> syntax, but
2240the indicated subroutine hasn't been defined, or if it was, it
2241has since been undefined.
2242
6fbc9859 2243=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2244S<<-- HERE> in m/%s/
1f4f6bf1
YO
2245
2246(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2247they must start with a non-digit word character. A common cause of
2248this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2249
5a25739d
FC
2250=item ()-group starts with a count
2251
2252(F) A ()-group started with a count. A count is supposed to follow
2253something: a template character or a ()-group. See L<perlfunc/pack>.
2254
fe13d51d 2255=item %s had compilation errors.
6df41af2
GS
2256
2257(F) The final summary message when a C<perl -c> fails.
2258
a0d0e21e
LW
2259=item Had to create %s unexpectedly
2260
be771a83
GS
2261(S internal) A routine asked for a symbol from a symbol table that ought
2262to have existed already, but for some reason it didn't, and had to be
2263created on an emergency basis to prevent a core dump.
a0d0e21e 2264
6df41af2
GS
2265=item %s has too many errors
2266
2267(F) The parser has given up trying to parse the program after 10 errors.
2268Further error messages would likely be uninformative.
2269
cc4d09e1
KW
2270=item Having more than one /%c regexp modifier is deprecated
2271
2272(D deprecated, regexp) You used the indicated regular expression pattern
2273modifier at least twice in a string of modifiers. It is deprecated to
2274do this with this particular modifier, to allow future extensions to the
2275Perl language.
2276
61e61fbc
JH
2277=item Hexadecimal float: exponent overflow
2278
d8f2b442 2279(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2280than the floating point supports.
2281
2282=item Hexadecimal float: exponent underflow
2283
d8f2b442 2284(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2285than the floating point supports.
2286
cf4f6003
JH
2287=item Hexadecimal float: internal error
2288
2289(F) Something went horribly bad in hexadecimal float handling.
2290
61e61fbc
JH
2291=item Hexadecimal float: mantissa overflow
2292
2293(W overflow) The hexadecimal floating point literal had more bits in
2294the mantissa (the part between the 0x and the exponent, also known as
2295the fraction or the significand) than the floating point supports.
2296
40bca5ae
JH
2297=item Hexadecimal float: precision loss
2298
2299(W overflow) The hexadecimal floating point had internally more
2300digits than could be output. This can be caused by unsupported
2301long double formats, or by 64-bit integers not being available
2302(needed to retrieve the digits under some configurations).
2303
2304=item Hexadecimal float: unsupported long double format
2305
2306(F) You have configured Perl to use long doubles but
d8f2b442 2307the internals of the long double format are unknown;
40bca5ae
JH
2308therefore the hexadecimal float output is impossible.
2309
252aa082
JH
2310=item Hexadecimal number > 0xffffffff non-portable
2311
e476b1b5 2312(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2313(4294967295) and therefore non-portable between systems. See
2314L<perlport> for more on portability concerns.
252aa082 2315
8903cb82
PP
2316=item Identifier too long
2317
2318(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2319about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2320names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2321of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2322
e0e4a6e3
FC
2323=item Ignoring zero length \N{} in character class in regex; marked by
2324S<<-- HERE> in m/%s/
fc8cd66c 2325
f3ba6905 2326(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2327zero-length sequence. When such an escape is used in a character class
2328its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2329been used, and the correct charname handler is in scope.
2330
6df41af2 2331=item Illegal binary digit %s
f675dbe5 2332
6df41af2 2333(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2334
6df41af2 2335=item Illegal binary digit %s ignored
a0d0e21e 2336
be771a83
GS
2337(W digit) You may have tried to use a digit other than 0 or 1 in a
2338binary number. Interpretation of the binary number stopped before the
2339offending digit.
a0d0e21e 2340
6597eb22
FC
2341=item Illegal character after '_' in prototype for %s : %s
2342
e4d150f1
FC
2343(W illegalproto) An illegal character was found in a prototype
2344declaration. The '_' in a prototype must be followed by a ';',
2345indicating the rest of the parameters are optional, or one of '@'
2346or '%', since those two will accept 0 or more final parameters.
6597eb22 2347
78d0fecf 2348=item Illegal character \%o (carriage return)
4fdae800 2349
d5898338 2350(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2351would any other whitespace, which means you should never see this error
2352when Perl was built using standard options. For some reason, your
2353version of Perl appears to have been built without this support. Talk
2354to your Perl administrator.
4fdae800 2355
d37a9538
ST
2356=item Illegal character in prototype for %s : %s
2357
197afce1 2358(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2359Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2360Perhaps you were trying to write a subroutine signature but didn't enable
2361that feature first (C<use feature 'signatures'>), so your signature was
2362instead interpreted as a bad prototype.
d37a9538 2363
904d85c5
RGS
2364=item Illegal declaration of anonymous subroutine
2365
2366(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2367you must always specify a block of code. See L<perlsub>.
904d85c5 2368
8e742a20
MHM
2369=item Illegal declaration of subroutine %s
2370
6903afa2 2371(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2372
a0d0e21e
LW
2373=item Illegal division by zero
2374
be771a83
GS
2375(F) You tried to divide a number by 0. Either something was wrong in
2376your logic, or you need to put a conditional in to guard against
2377meaningless input.
a0d0e21e 2378
6df41af2
GS
2379=item Illegal hexadecimal digit %s ignored
2380
be771a83
GS
2381(W digit) You may have tried to use a character other than 0 - 9 or
2382A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2383number stopped before the illegal character.
6df41af2 2384
a0d0e21e
LW
2385=item Illegal modulus zero
2386
be771a83
GS
2387(F) You tried to divide a number by 0 to get the remainder. Most
2388numbers don't take to this kindly.
a0d0e21e 2389
6df41af2 2390=item Illegal number of bits in vec
399388f4 2391
6df41af2
GS
2392(F) The number of bits in vec() (the third argument) must be a power of
2393two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2394
2395=item Illegal octal digit %s
a0d0e21e 2396
d1be9408 2397(F) You used an 8 or 9 in an octal number.
a0d0e21e 2398
399388f4 2399=item Illegal octal digit %s ignored
748a9306 2400
d1be9408 2401(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2402Interpretation of the octal number stopped before the 8 or 9.
748a9306 2403
e0e4a6e3 2404=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2405
675fa9ff 2406(F) You wrote something like
c608e803
KW
2407
2408 (?+foo)
2409
2410The C<"+"> is valid only when followed by digits, indicating a
2411capturing group. See
2412L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2413
375ed12a
JH
2414=item Illegal suidscript
2415
2416(F) The script run under suidperl was somehow illegal.
2417
fe13d51d 2418=item Illegal switch in PERL5OPT: -%c
6ff81951 2419
6df41af2 2420(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2421following switches: B<-[CDIMUdmtw]>.
6ff81951 2422
6df41af2 2423=item Ill-formed CRTL environ value "%s"
81e118e0 2424
75b44862 2425(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2426internal environ array, and encountered an element without the C<=>
2427delimiter used to separate keys from values. The element is ignored.
09bef843 2428
6df41af2 2429=item Ill-formed message in prime_env_iter: |%s|
54310121 2430
be771a83
GS
2431(W internal) A warning peculiar to VMS. Perl tried to read a logical
2432name or CLI symbol definition when preparing to iterate over %ENV, and
2433didn't see the expected delimiter between key and value, so the line was
2434ignored.
54310121 2435
6df41af2 2436=item (in cleanup) %s
9607fc9c 2437
be771a83
GS
2438(W misc) This prefix usually indicates that a DESTROY() method raised
2439the indicated exception. Since destructors are usually called by the
2440system at arbitrary points during execution, and often a vast number of
2441times, the warning is issued only once for any number of failures that
2442would otherwise result in the same message being repeated.
6df41af2 2443
be771a83
GS
2444Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2445also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2446
e0e4a6e3
FC
2447=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2448in m/%s/
0d0b4b3b 2449
675fa9ff 2450(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2451expression inside the construct was completely empty, or if there are
2452too many or few operands for the number of operators. Perl is not smart
2453enough to give you a more precise indication as to what is wrong.
2454
6fbc9859
MH
2455=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2456parent '%s'
2c7d6b9c
RGS
2457
2458(F) The method resolution order (MRO) of the given class is not
2459C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2460documentation in L<mro> for more information.
2461
979699d9
JH
2462=item In EBCDIC the v-string components cannot exceed 2147483647
2463
2464(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2465Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2466encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2467
6a2ed79a 2468=item Infinite recursion in regex
1a147d38
YO
2469
2470(F) You used a pattern that references itself without consuming any input
6903afa2 2471text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2472either consume text or fail.
2473
6dbe9451
NC
2474=item Initialization of state variables in list context currently forbidden
2475
6903afa2
FC
2476(F) Currently the implementation of "state" only permits the
2477initialization of scalar variables in scalar context. Re-write
2478C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2479context. Constructions such as C<state (@a) = foo()> will be
2480supported in a future perl release.
6dbe9451 2481
2186f873
FC
2482=item %%s[%s] in scalar context better written as $%s[%s]
2483
2484(W syntax) In scalar context, you've used an array index/value slice
2485(indicated by %) to select a single element of an array. Generally
2486it's better to ask for a scalar value (indicated by $). The difference
2487is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2488returns and when evaluating its argument, while C<%foo[&bar]> provides
2489a list context to its subscript, which can do weird things if you're
2490expecting only one subscript. When called in list context, it also
2491returns the index (what C<&bar> returns) in addition to the value.
2492
2493=item %%s{%s} in scalar context better written as $%s{%s}
2494
2495(W syntax) In scalar context, you've used a hash key/value slice
2496(indicated by %) to select a single element of a hash. Generally it's
2497better to ask for a scalar value (indicated by $). The difference
2498is that C<$foo{&bar}> always behaves like a scalar, both in the value
2499it returns and when evaluating its argument, while C<@foo{&bar}> and
2500provides a list context to its subscript, which can do weird things
2501if you're expecting only one subscript. When called in list context,
2502it also returns the key in addition to the value.
2503
a0d0e21e
LW
2504=item Insecure dependency in %s
2505
8b1a09fc 2506(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2507The tainting mechanism is turned on when you're running setuid or
2508setgid, or when you specify B<-T> to turn it on explicitly. The
2509tainting mechanism labels all data that's derived directly or indirectly
2510from the user, who is considered to be unworthy of your trust. If any
2511such data is used in a "dangerous" operation, you get this error. See
2512L<perlsec> for more information.
a0d0e21e
LW
2513
2514=item Insecure directory in %s
2515
be771a83
GS
2516(F) You can't use system(), exec(), or a piped open in a setuid or
2517setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2518the world. Also, the PATH must not contain any relative directory.
2519See L<perlsec>.
a0d0e21e 2520
62f468fc 2521=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2522
2523(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2524setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2525C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2526supplied (or potentially supplied) by the user. The script must set
2527the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2528
0e9be77f
DM
2529=item Insecure user-defined property %s
2530
2531(F) Perl detected tainted data when trying to compile a regular
2532expression that contains a call to a user-defined character property
2533function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2534See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2535
b9ef414d
FC
2536=item Integer overflow in format string for %s
2537
2538(F) The indexes and widths specified in the format string of C<printf()>
2539or C<sprintf()> are too large. The numbers must not overflow the size of
2540integers for your architecture.
2541
a7ae9550
GS
2542=item Integer overflow in %s number
2543
35928bc5 2544(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2545either as a literal or as an argument to hex() or oct() is too big for
2546your architecture, and has been converted to a floating point number.
2547On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2548representable without overflow is 0xFFFFFFFF, 037777777777, or
25490b11111111111111111111111111111111 respectively. Note that Perl
2550transparently promotes all numbers to a floating point representation
2551internally--subject to loss of precision errors in subsequent
2552operations.
bbce6d69 2553
fc89ca81
FC
2554=item Integer overflow in srand
2555
2556(S overflow) The number you have passed to srand is too big to fit
2557in your architecture's integer representation. The number has been
2558replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2559architectures). This means you may be getting less randomness than
2560you expect, because different random seeds above the maximum will
2561return the same sequence of random numbers.
2562
46314c13
JP
2563=item Integer overflow in version
2564
18da5252
FC
2565=item Integer overflow in version %d
2566
784d71ed
FC
2567(W overflow) Some portion of a version initialization is too large for
2568the size of integers for your architecture. This is not a warning
f084e84f 2569because there is no rational reason for a version to try and use an
784d71ed
FC
2570element larger than typically 2**32. This is usually caused by trying
2571to use some odd mathematical operation as a version, like 100/9.
46314c13 2572
e0e4a6e3 2573=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2574
2575(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2576The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2577discovered.
2578
748a9306
LW
2579=item Internal inconsistency in tracking vforks
2580
be771a83
GS
2581(S) A warning peculiar to VMS. Perl keeps track of the number of times
2582you've called C<fork> and C<exec>, to determine whether the current call
2583to C<exec> should affect the current script or a subprocess (see
2584L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2585Perl is making a guess and treating this C<exec> as a request to
2586terminate the Perl script and execute the specified command.
748a9306 2587
870978ae
FC
2588=item internal %<num>p might conflict with future printf extensions
2589
2590(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2591formatting follows a slightly different set of rules when called from
2592C or XS code. Specifically, formats consisting of digits followed
2593by "p" (e.g., "%7p") are reserved for future use. If you see this
2594message, then an XS module tried to call that routine with one such
2595reserved format.
2596
e0e4a6e3 2597=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2598
fa816bf3 2599(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2600S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2601discovered.
a0d0e21e 2602
6df41af2
GS
2603=item %s (...) interpreted as function
2604
75b44862 2605(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2606followed by parentheses turns into a function, with all the list
64977eb6 2607operators arguments found inside the parentheses. See
13a2d996 2608L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2609
f51551f7
FC
2610=item In '(?...)', the '(' and '?' must be adjacent in regex;
2611marked by S<<-- HERE> in m/%s/
2612
2613(F) The two-character sequence C<"(?"> in this context in a regular
2614expression pattern should be an indivisible token, with nothing
2615intervening between the C<"("> and the C<"?">, but you separated them
2616with whitespace.
2617
09bef843
SB
2618=item Invalid %s attribute: %s
2619
a4a4c9e2 2620(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2621by Perl or by a user-supplied handler. See L<attributes>.
2622
2623=item Invalid %s attributes: %s
2624
a4a4c9e2 2625(F) The indicated attributes for a subroutine or variable were not
be771a83 2626recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2627
e0e4a6e3
FC
2628=item Invalid character in charnames alias definition; marked by
2629S<<-- HERE> in '%s
225fb84f
KW
2630
2631(F) You tried to create a custom alias for a character name, with
2632the C<:alias> option to C<use charnames> and the specified character in
2633the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2634
c8028aa6
TC
2635=item Invalid \0 character in %s for %s: %s\0%s
2636
fa3234e3
FC
2637(W syscalls) Embedded \0 characters in pathnames or other system call
2638arguments produce a warning as of 5.20. The parts after the \0 were
2639formerly ignored by system calls.
c8028aa6 2640
e0e4a6e3 2641=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2642
2643(F) Only certain characters are valid for character names. The
2644indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2645
c635e13b
PP
2646=item Invalid conversion in %s: "%s"
2647
be771a83
GS
2648(W printf) Perl does not understand the given format conversion. See
2649L<perlfunc/sprintf>.
c635e13b 2650
e0e4a6e3
FC
2651=item Invalid escape in the specified encoding in regex; marked by
2652S<<-- HERE> in m/%s/
9e08bc66 2653
98d31c73 2654(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2655didn't correspond to a single character through the conversion
2656from the encoding specified by the encoding pragma.
98d31c73
FC
2657The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2658instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2659The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2660escape was discovered.
2661
8149aa9f
FC
2662=item Invalid hexadecimal number in \N{U+...}
2663
e0e4a6e3
FC
2664=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2665S<<-- HERE> in m/%s/
aec0ef10 2666
8149aa9f 2667(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2668number. Either it is empty, or you tried to use a character other than
26690 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2670
6651ba0b
FC
2671=item Invalid module name %s with -%c option: contains single ':'
2672
2673(F) The module argument to perl's B<-m> and B<-M> command-line options
2674cannot contain single colons in the module name, but only in the
2675arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2676B<-MFoo:Bar=baz> is not.
2677
2c7d6b9c
RGS
2678=item Invalid mro name: '%s'
2679
162a3e34
FC
2680(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2681where C<foo> is not a valid method resolution order (MRO). Currently,
2682the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2683a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2684
40e4140b
FC
2685=item Invalid negative number (%s) in chr
2686
2687(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2688not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2689character (U+FFFD).
2690
6651ba0b
FC
2691=item invalid option -D%c, use -D'' to see choices
2692
8ff21bfe
FC
2693(S debugging) Perl was called with invalid debugger flags. Call perl
2694with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2695See also L<perlrun/-Dletters>.
6651ba0b 2696
e0e4a6e3 2697=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2698
2699(F) The range specified in a character class had a minimum character
7253e4e3
RK
2700greater than the maximum character. One possibility is that you forgot the
2701C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2702up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2703problem was discovered. See L<perlre>.
6df41af2 2704
d1573ac7 2705=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2706
2707(F) The range specified in the tr/// or y/// operator had a minimum
2708character greater than the maximum character. See L<perlop>.
2709
09bef843
SB
2710=item Invalid separator character %s in attribute list
2711
0120eecf 2712(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2713elements of an attribute list. If the previous attribute had a
2714parenthesised parameter list, perhaps that list was terminated too soon.
2715See L<attributes>.
09bef843 2716
b4581f09
JH
2717=item Invalid separator character %s in PerlIO layer specification %s
2718
2bfc5f71
FC
2719(W layer) When pushing layers onto the Perl I/O system, something other
2720than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2721If the previous attribute had a parenthesised parameter list, perhaps that
2722list was terminated too soon.
2723
2c86d456
DG
2724=item Invalid strict version format (%s)
2725
fa816bf3 2726(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2727A "strict" version number is a positive decimal number (integer or
2728decimal-fraction) without exponentiation or else a dotted-decimal
2729v-string with a leading 'v' character and at least three components.
a6485a24 2730The parenthesized text indicates which criteria were not met.
2c86d456
DG
2731See the L<version> module for more details on allowed version formats.
2732
49704364 2733=item Invalid type '%s' in %s
96e4d5b1 2734
49704364
LW
2735(F) The given character is not a valid pack or unpack type.
2736See L<perlfunc/pack>.
6728c851 2737
49704364 2738(W) The given character is not a valid pack or unpack type but used to be
75b44862 2739silently ignored.
96e4d5b1 2740
2c86d456
DG
2741=item Invalid version format (%s)
2742
fa816bf3 2743(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2744A "lax" version number is a positive decimal number (integer or
2745decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2746v-string. If the v-string has fewer than three components, it
2747must have a leading 'v' character. Otherwise, the leading 'v' is
2748optional. Both decimal and dotted-decimal versions may have a
2749trailing "alpha" component separated by an underscore character
2750after a fractional or dotted-decimal component. The parenthesized
2751text indicates which criteria were not met. See the L<version> module
2752for more details on allowed version formats.
46314c13 2753
798ae1b7
DG
2754=item Invalid version object
2755
fa816bf3
FC
2756(F) The internal structure of the version object was invalid.
2757Perhaps the internals were modified directly in some way or
2758an arbitrary reference was blessed into the "version" class.
798ae1b7 2759
cd209d9d 2760=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2761marked by S<<-- HERE> in m/%s/
675fa9ff 2762
cd209d9d 2763(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2764this context in a regular expression pattern should be an
2765indivisible token, with nothing intervening between the C<"(">
cd209d9d 2766and the C<"*">, but you separated them.
675fa9ff 2767
a0d0e21e
LW
2768=item ioctl is not implemented
2769
2770(F) Your machine apparently doesn't implement ioctl(), which is pretty
2771strange for a machine that supports C.
2772
c289d2f7
JH
2773=item ioctl() on unopened %s
2774
2775(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2776Check your control flow and number of arguments.
c289d2f7 2777
fe13d51d 2778=item IO layers (like '%s') unavailable
363c40c4
SB
2779
2780(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2781you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2782with 'useperlio'.
2783
80cbd5ad
JH
2784=item IO::Socket::atmark not implemented on this architecture
2785
2786(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2787neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2788
4f650b80 2789=item $* is no longer supported
b4581f09 2790
4f650b80 2791(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2792perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2793previous versions of perl the use of C<$*> enabled or disabled multi-line
2794matching within a string.
4fd19576
B
2795
2796Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2797modifiers. You can enable C</m> for a lexical scope (even a whole file)
2798with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2799then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2800
8ae1fe26
RGS
2801=item $# is no longer supported
2802
a58ac25e 2803(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2804perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2805should use the printf/sprintf functions instead.
8ae1fe26 2806
ccf3535a 2807=item '%s' is not a code reference
6ad11d81 2808
6903afa2
FC
2809(W overload) The second (fourth, sixth, ...) argument of
2810overload::constant needs to be a code reference. Either
2811an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2812
ccf3535a 2813=item '%s' is not an overloadable type
6ad11d81 2814
04a80ee0
RGS
2815(W overload) You tried to overload a constant type the overload package is
2816unaware of.
6ad11d81 2817
5a25739d
FC
2818=item -i used with no filenames on the command line, reading from STDIN
2819
2820(S inplace) The C<-i> option was passed on the command line, indicating
2821that the script is intended to edit files in place, but no files were
2822given. This is usually a mistake, since editing STDIN in place doesn't
2823make sense, and can be confusing because it can make perl look like
2824it is hanging when it is really just trying to read from STDIN. You
2825should either pass a filename to edit, or remove C<-i> from the command
2826line. See L<perlrun> for more details.
2827
aec0ef10 2828=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2829
2830(P) The regular expression parser is confused.
2831
0953b66b
FC
2832=item keys on reference is experimental
2833
0773cb3e
FC
2834(S experimental::autoderef) C<keys> with a scalar argument is experimental
2835and may change or be removed in a future Perl version. If you want to
2836take the risk of using this feature, simply disable this warning:
0953b66b 2837
d401967c 2838 no warnings "experimental::autoderef";
0953b66b 2839
a0d0e21e
LW
2840=item Label not found for "last %s"
2841
be771a83
GS
2842(F) You named a loop to break out of, but you're not currently in a loop
2843of that name, not even if you count where you were called from. See
2844L<perlfunc/last>.
a0d0e21e
LW
2845
2846=item Label not found for "next %s"
2847
2848(F) You named a loop to continue, but you're not currently in a loop of
2849that name, not even if you count where you were called from. See
2850L<perlfunc/last>.
2851
2852=item Label not found for "redo %s"
2853
2854(F) You named a loop to restart, but you're not currently in a loop of
2855that name, not even if you count where you were called from. See
2856L<perlfunc/last>.
2857
85ab1d1d 2858=item leaving effective %s failed
5ff3f7a4 2859
85ab1d1d 2860(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2861effective uids or gids failed.
2862
49704364
LW
2863=item length/code after end of string in unpack
2864
d7f8936a 2865(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2866length/code combination tried to obtain more data. This results in
2867an undefined value for the length. See L<perlfunc/pack>.
49704364 2868
25e26107 2869=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2870
0d46a4e7
FC
2871(W syntax) You used length() on either an array or a hash when you
2872probably wanted a count of the items.
e508c8a4
MH
2873
2874Array size can be obtained by doing:
2875
2876 scalar(@array);
2877
2878The number of items in a hash can be obtained by doing:
2879
2880 scalar(keys %hash);
2881
f0e67a1d
Z
2882=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2883
d4fe7078
RS
2884(F) An extension is attempting to insert text into the current parse
2885(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2886couldn't be part of the current input. This is an inherent pitfall
2887of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2888it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2889
2890=item Lexing code internal error (%s)
2891
2892(F) Lexing code supplied by an extension violated the lexer's API in a
2893detectable way.
2894
69282e91 2895=item listen() on closed socket %s
a0d0e21e 2896
be771a83
GS
2897(W closed) You tried to do a listen on a closed socket. Did you forget
2898to check the return value of your socket() call? See
2899L<perlfunc/listen>.
a0d0e21e 2900
6651ba0b
FC
2901=item List form of piped open not implemented
2902
2903(F) On some platforms, notably Windows, the three-or-more-arguments
2904form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2905Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2906
b35b96b6
JH
2907=item localtime(%f) failed
2908
2909(W overflow) You called C<localtime> with a number that it could not handle:
2910too large, too small, or NaN. The returned value is C<undef>.
2911
bcd05b94 2912=item localtime(%f) too large
8b56d6ff 2913
e9200be3 2914(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2915than it can reliably handle and C<localtime> probably returned the
6903afa2 2916wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2917not-a-number value).
2918
bcd05b94 2919=item localtime(%f) too small
fc003d4b 2920
e9200be3 2921(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2922than it can reliably handle and C<localtime> probably returned the
e7a1a147 2923wrong date.
8b56d6ff 2924
58e23c8d 2925=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2926
2927(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2928handle. This restriction may be eased in a future release.
2e50fd82 2929
b88df990
NC
2930=item Lost precision when %s %f by 1
2931
e63e8a91
FC
2932(W imprecision) The value you attempted to increment or decrement by one
2933is too large for the underlying floating point representation to store
2934accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2935warning because it has already switched from integers to floating point
2936when values are too large for integers, and now even floating point is
2937insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2938
93fad930 2939=item lstat() on filehandle%s
2f7da168
RK
2940
2941(W io) You tried to do an lstat on a filehandle. What did you mean
2942by that? lstat() makes sense only on filenames. (Perl did a fstat()
2943instead on the filehandle.)
2944
345d70e3 2945=item lvalue attribute %s already-defined subroutine
bb3abb05 2946
345d70e3
FC
2947(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2948attribute on or off on a Perl subroutine that is already defined
2949does not always work properly. It may or may not do what you
2950want, depending on what code is inside the subroutine, with exact
2951details subject to change between Perl versions. Only do this
2952if you really know what you are doing.
bb3abb05 2953
885ef6f5
GG
2954=item lvalue attribute ignored after the subroutine has been defined
2955
345d70e3
FC
2956(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2957subroutine an lvalue subroutine after it has been defined is
2958not permitted. To make the subroutine an lvalue subroutine,
2959add the lvalue attribute to the definition, or put the C<sub
2960foo :lvalue;> declaration before the definition.
2961
2962See also L<attributes.pm|attributes>.
885ef6f5 2963
6f1b3ab0
FC
2964=item Magical list constants are not supported
2965
2966(F) You assigned a magical array to a stash element, and then tried
2967to use the subroutine from the same slot. You are asking Perl to do
2968something it cannot do, details subject to change between Perl versions.
2969
2db62bbc 2970=item Malformed integer in [] in pack
49704364 2971
2db62bbc 2972(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2973are permitted. See L<perlfunc/pack>.
2974
2975=item Malformed integer in [] in unpack
2976
2db62bbc 2977(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2978are permitted. See L<perlfunc/pack>.
2979
6df41af2
GS
2980=item Malformed PERLLIB_PREFIX
2981
2982(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2983
2984 prefix1;prefix2
2985
2986or
6df41af2
GS
2987 prefix1 prefix2
2988
be771a83
GS
2989with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2990a builtin library search path, prefix2 is substituted. The error may
2991appear if components are not found, or are too long. See
fecfaeb8 2992"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2993
2f758a16
ST
2994=item Malformed prototype for %s: %s
2995
d37a9538
ST
2996(F) You tried to use a function with a malformed prototype. The
2997syntax of function prototypes is given a brief compile-time check for
2998obvious errors like invalid characters. A more rigorous check is run
2999when the function is called.
30d9c59b
Z
3000Perhaps the function's author was trying to write a subroutine signature
3001but didn't enable that feature first (C<use feature 'signatures'>),
3002so the signature was instead interpreted as a bad prototype.
2f758a16 3003
ba210ebe
JH
3004=item Malformed UTF-8 character (%s)
3005
4d6f11e5 3006(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3007encoding rules, even though it had the UTF8 flag on.
ba210ebe 3008
2575c402
JW
3009One possible cause is that you set the UTF8 flag yourself for data that
3010you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 30118-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3012
3013If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3014sequences are handled gracefully, but if you use C<:utf8>, the flag is
3015set without validating the data, possibly resulting in this error
3016message.
3017
3018See also L<Encode/"Handling Malformed Data">.
901b21bf 3019
107160e2
KW
3020=item Malformed UTF-8 character immediately after '%s'
3021
3022(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3023encoding rules. The message prints out the properly encoded characters
3024just before the first bad one. If C<utf8> warnings are enabled, a
3025warning is generated that gives more details about the type of
3026malformation.
3027
bde9e88d 3028=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3029
3030(F) The charnames handler returned malformed UTF-8.
3031
4a5d3a93
FC
3032=item Malformed UTF-8 string in '%c' format in unpack
3033
3034(F) You tried to unpack something that didn't comply with UTF-8 encoding
3035rules and perl was unable to guess how to make more progress.
3036
f337b084
TH
3037=item Malformed UTF-8 string in pack
3038
3039(F) You tried to pack something that didn't comply with UTF-8 encoding
3040rules and perl was unable to guess how to make more progress.
3041
3042=item Malformed UTF-8 string in unpack
3043
3044(F) You tried to unpack something that didn't comply with UTF-8 encoding
3045rules and perl was unable to guess how to make more progress.
3046
4a5d3a93 3047=item Malformed UTF-16 surrogate
f337b084 3048
4a5d3a93
FC
3049(F) Perl thought it was reading UTF-16 encoded character data but while
3050doing it Perl met a malformed Unicode surrogate.
3051
30d9c59b
Z
3052=item Mandatory parameter follows optional parameter
3053
3054(F) In a subroutine signature, you wrote something like "$a = undef,
3055$b", making an earlier parameter optional and a later one mandatory.
3056Parameters are filled from left to right, so it's impossible for the
3057caller to omit an earlier one and pass a later one. If you want to act
3058as if the parameters are filled from right to left, declare the rightmost
3059optional and then shuffle the parameters around in the subroutine's body.
3060
2d88a86a
KW
3061=item Matched non-Unicode code point 0x%X against Unicode property; may
3062not be portable
3063
3064(S non_unicode) Perl allows strings to contain a superset of
3065Unicode code points; each code point may be as large as what is storable
3066in an unsigned integer on your system, but these may not be accepted by
3067other languages/systems. This message occurs when you matched a string
3068containing such a code point against a regular expression pattern, and
3069the code point was matched against a Unicode property, C<\p{...}> or
3070C<\P{...}>. Unicode properties are only defined on Unicode code points,
3071so the result of this match is undefined by Unicode, but Perl (starting
3072in v5.20) treats non-Unicode code points as if they were typical
3073unassigned Unicode ones, and matched this one accordingly. Whether a
3074given property matches these code points or not is specified in
3075L<perluniprops/Properties accessible through \p{} and \P{}>.
3076
3077This message is suppressed (unless it has been made fatal) if it is
3078immaterial to the results of the match if the code point is Unicode or
3079not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3080the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3081Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3082every code point except these 22.)
3083
3084Getting this message indicates that the outcome of the match arguably
3085should have been the opposite of what actually happened. If you think
3086that is the case, you may wish to make the C<non_unicode> warnings
3087category fatal; if you agree with Perl's decision, you may wish to turn
3088off this category.
3089
3090See L<perlunicode/Beyond Unicode code points> for more information.
3091
e0e4a6e3
FC
3092=item %s matches null string many times in regex; marked by S<<-- HERE> in
3093m/%s/
4a5d3a93
FC
3094
3095(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3096regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3097shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3098See L<perlre>.
f337b084 3099
de42a5a9 3100=item Maximal count of pending signals (%u) exceeded
2563cec5 3101
6903afa2 3102(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3103usually indicates that your operating system tried to deliver signals
3104too fast (with a very high priority), starving the perl process from
3105resources it would need to reach a point where it can process signals
6903afa2 3106safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3107
25f58aea
PN
3108=item "%s" may clash with future reserved word
3109
3110(W) This warning may be due to running a perl5 script through a perl4
3111interpreter, especially if the word that is being warned about is
3112"use" or "my".
3113
0d2487cd 3114=item '%' may not be used in pack
6df41af2
GS
3115
3116(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3117checksumming process loses information, and you can't go the other way.
3118See L<perlfunc/unpack>.
6df41af2 3119
a0d0e21e
LW
3120=item Method for operation %s not found in package %s during blessing
3121
3122(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3123doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3124
3cdd684c
TP
3125=item Method %s not permitted
3126
3127See Server error.
3128
a0d0e21e
LW
3129=item Might be a runaway multi-line %s string starting on line %d
3130
3131(S) An advisory indicating that the previous error may have been caused
3132by a missing delimiter on a string or pattern, because it eventually
3133ended earlier on the current line.
3134
3135=item Misplaced _ in number
3136
d4ced10d
JH
3137(W syntax) An underscore (underbar) in a numeric constant did not
3138separate two digits.
a0d0e21e 3139
7baa4690
HS
3140=item Missing argument in %s
3141
3664866e
AB
3142(W missing) You called a function with fewer arguments than other
3143arguments you supplied indicated would be needed.
3144
3145Currently only emitted when a printf-type format required more
3146arguments than were supplied, but might be used in the future for
3147other cases where we can statically determine that arguments to
3148functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3149
9e81e6a1
RGS
3150=item Missing argument to -%c
3151
3152(F) The argument to the indicated command line switch must follow
3153immediately after the switch, without intervening spaces.
3154
ff3f963a 3155=item Missing braces on \N{}
423cee85 3156
e0e4a6e3 3157=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3158
4a2d328f 3159(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3160double-quotish context. This can also happen when there is a space
3161(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3162This modifier does not change the requirement that the brace immediately
3163follow the C<\N>.
423cee85 3164
f0a2b745
KW
3165=item Missing braces on \o{}
3166
3167(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3168
a0d0e21e
LW
3169=item Missing comma after first argument to %s function
3170
3171(F) While certain functions allow you to specify a filehandle or an
3172"indirect object" before the argument list, this ain't one of them.
3173
06eaf0bc
GS
3174=item Missing command in piped open
3175
be771a83
GS
3176(W pipe) You used the C<open(FH, "| command")> or
3177C<open(FH, "command |")> construction, but the command was missing or
3178blank.
06eaf0bc 3179
961ce445
RGS
3180=item Missing control char name in \c
3181
3182(F) A double-quoted string ended with "\c", without the required control
3183character name.
3184
591f5ca2
FC
3185=item Missing ']' in prototype for %s : %s
3186
bfe11873 3187(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3188
8767b1ab 3189=item Missing name in "%s sub"
6df41af2 3190
87444db5 3191(F) The syntax for lexically scoped subroutines requires that
be771a83 3192they have a name with which they can be found.
6df41af2
GS
3193
3194=item Missing $ on loop variable
3195
be771a83
GS
3196(F) Apparently you've been programming in B<csh> too much. Variables
3197are always mentioned with the $ in Perl, unlike in the shells, where it
3198can vary from one line to the next.
6df41af2 3199
cc507455 3200=item (Missing operator before %s?)
748a9306 3201
56da5a46
RGS
3202(S syntax) This is an educated guess made in conjunction with the message
3203"%s found where operator expected". Often the missing operator is a comma.
748a9306 3204
f51551f7
FC
3205=item Missing or undefined argument to require
3206
3207(F) You tried to call require with no argument or with an undefined
3208value as an argument. Require expects either a package name or a
3209file-specification as an argument. See L<perlfunc/require>.
3210
e0e4a6e3 3211=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3212
ff3f963a
KW
3213(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3214
4a68bf9d 3215=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3216
d32207c9
FC
3217(F) C<\N> has two meanings.
3218
3219The traditional one has it followed by a name enclosed in braces,
3220meaning the character (or sequence of characters) given by that
fa816bf3 3221name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3222double-quoted strings and regular expression patterns. In patterns,
3223it doesn't have the meaning an unescaped C<*> does.
3224
3225Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3226in patterns, namely to match a non-newline character. (This is short
3227for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3228
3229This can lead to some ambiguities. When C<\N> is not followed immediately
3230by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3231form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3232means to match the given quantity of non-newlines (in these examples,
32333; and 5 or more, respectively). In all other case, where there is a
3234C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3235
3236However, if there is no matching C<}>, Perl doesn't know if it was
3237mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3238If you meant the former, add the right brace; if you meant the latter,
3239escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3240
d98d5fff 3241=item Missing right curly or square bracket
a0d0e21e 3242
be771a83
GS
3243(F) The lexer counted more opening curly or square brackets than closing
3244ones. As a general rule, you'll find it's missing near the place you
3245were last editing.
a0d0e21e 3246
6df41af2
GS
3247=item (Missing semicolon on previous line?)
3248
56da5a46
RGS
3249(S syntax) This is an educated guess made in conjunction with the message
3250"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3251the previous line just because you saw this message.
3252
a0d0e21e
LW
3253=item Modification of a read-only value attempted
3254
3255(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3256constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3257catches that. But an easy way to do the same thing is:
3258
3259 sub mod { $_[0] = 1 }
3260 mod(2);
3261
3262Another way is to assign to a substr() that's off the end of the string.
3263
c5674021
PDF
3264Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3265is aliased to a constant in the look I<LIST>:
3266
b7e4ecc1
FC
3267 $x = 1;
3268 foreach my $n ($x, 2) {
3269 $n *= 2; # modifies the $x, but fails on attempt to
3270 } # modify the 2
c5674021 3271
7a4340ed 3272=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3273
3274(F) You tried to make an array value spring into existence, and the
3275subscript was probably negative, even counting from end of the array
3276backwards.
3277
7a4340ed 3278=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3279
be771a83
GS
3280(P) You tried to make a hash value spring into existence, and it
3281couldn't be created for some peculiar reason.
a0d0e21e
LW
3282
3283=item Module name must be constant
3284
3285(F) Only a bare module name is allowed as the first argument to a "use".
3286
be98fb35 3287=item Module name required with -%c option
6df41af2 3288
be98fb35
GS
3289(F) The C<-M> or C<-m> options say that Perl should load some module, but
3290you omitted the name of the module. Consult L<perlrun> for full details
3291about C<-M> and C<-m>.
6df41af2 3292
fe13d51d 3293=item More than one argument to '%s' open
ed9aa3b7 3294
6903afa2 3295(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3296can happen if you are trying to open a pipe to a command that takes a
3297list of arguments, but have forgotten to specify a piped open mode.
3298See L<perlfunc/open> for details.
3299
85396b18
FC
3300=item mprotect for COW string %p %u failed with %d
3301
3302(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3303L<perlguts/"Copy on Write">), but a shared string buffer
3304could not be made read-only.
3305
92951bce
FC
3306=item mprotect for %p %u failed with %d
3307
85396b18
FC
3308(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3309but an op tree could not be made read-only.
3310
3311=item mprotect RW for COW string %p %u failed with %d
3312
3313(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3314L<perlguts/"Copy on Write">), but a read-only shared string
3315buffer could not be made mutable.
3316
92951bce
FC
3317=item mprotect RW for %p %u failed with %d
3318
3319(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3320L<perlhacktips>), but a read-only op tree could not be made
3321mutable before freeing the ops.
92951bce 3322
a0d0e21e
LW
3323=item msg%s not implemented
3324