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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
NC
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
f1a3ce43
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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
PP
417=item Bad hash
418
419(P) One of the internal hash routines was passed a null HV pointer.
420
6df41af2
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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
IZ
446=item Bad realloc() ignored
447
6903afa2
FC
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
a0d0e21e
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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
4df3f177
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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
a0d0e21e
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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.
a0d0e21e
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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
34d09196
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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
GS
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
GS
482
483 use constant TYPO => 1;
484 if (TYOP) { print "foo" }
485
486The C<strict> pragma is useful in avoiding such errors.
487
6df41af2
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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
PP
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
JH
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
9a189793 552=item %s: Invalid handshake key got %p needed %p, binaries are mismatched
db6e00bd
DD
553
554(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
555process that was built against a different build of perl than the said
9a189793
DD
556library was compiled against. Reinstalling the XS module will likely fix this
557error.
db6e00bd 558
f675dbe5
CB
559=item Buffer overflow in prime_env_iter: %s
560
be771a83
GS
561(W internal) A warning peculiar to VMS. While Perl was preparing to
562iterate over %ENV, it encountered a logical name or symbol definition
563which was too long, so it was truncated to the string shown.
f675dbe5 564
a0d0e21e
LW
565=item Callback called exit
566
4929bf7b 567(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
568exited by calling exit.
569
6df41af2 570=item %s() called too early to check prototype
f675dbe5 571
be771a83
GS
572(W prototype) You've called a function that has a prototype before the
573parser saw a definition or declaration for it, and Perl could not check
574that the call conforms to the prototype. You need to either add an
575early prototype declaration for the subroutine in question, or move the
576subroutine definition ahead of the call to get proper prototype
577checking. Alternatively, if you are certain that you're calling the
578function correctly, you may put an ampersand before the name to avoid
579the warning. See L<perlsub>.
f675dbe5 580
56feebad
FC
581=item Calling POSIX::%s() is deprecated
582
583(D deprecated) You called a function whose use is deprecated. See
584the function's name in L<POSIX> for details.
585
0c7df902
JH
586=item Cannot chr %f
587
588(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
589
5dee29d4 590=item Cannot compress %f in pack
0c7df902 591
5dee29d4
JH
592(F) You tried compressing an infinity or not-a-number as an unsigned
593integer with BER, which makes no sense.
0c7df902 594
49704364 595=item Cannot compress integer in pack
0258719b 596
717feafc
JH
597(F) An argument to pack("w",...) was too large to compress.
598The BER compressed integer format can only be used with positive
599integers, and you attempted to compress a very large number (> 1e308).
600See L<perlfunc/pack>.
0258719b 601
49704364 602=item Cannot compress negative numbers in pack
0258719b
NC
603
604(F) An argument to pack("w",...) was negative. The BER compressed integer
605format can only be used with positive integers. See L<perlfunc/pack>.
606
5c1f4d79
NC
607=item Cannot convert a reference to %s to typeglob
608
6903afa2
FC
609(F) You manipulated Perl's symbol table directly, stored a reference
610in it, then tried to access that symbol via conventional Perl syntax.
611The access triggers Perl to autovivify that typeglob, but it there is
612no legal conversion from that type of reference to a typeglob.
5c1f4d79 613
4040665a 614=item Cannot copy to %s
ba2fdce6
NC
615
616(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 617be directly assigned to.
ba2fdce6 618
b5d97229
RGS
619=item Cannot find encoding "%s"
620
621(S io) You tried to apply an encoding that did not exist to a filehandle,
622either with open() or binmode().
623
0c7df902
JH
624=item Cannot pack %f with '%c'
625
5dee29d4 626(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
627which makes no sense.
628
629=item Cannot printf %f with '%c'
630
631(F) You tried printing an infinity or not-a-number as a character (%c),
632which makes no sense. Maybe you meant '%s', or just stringifying it?
633
7355df7e
FC
634=item Cannot set tied @DB::args
635
636(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
637is not supported. (Before this error was added, it used to crash.)
638
ce65bc73
FC
639=item Cannot tie unreifiable array
640
641(P) You somehow managed to call C<tie> on an array that does not
642keep a reference count on its arguments and cannot be made to
643do so. Such arrays are not even supposed to be accessible to
644Perl code, but are only used internally.
645
96ebfdd7
RK
646=item Can only compress unsigned integers in pack
647
648(F) An argument to pack("w",...) was not an integer. The BER compressed
649integer format can only be used with positive integers, and you attempted
650to compress something else. See L<perlfunc/pack>.
651
a0d0e21e
LW
652=item Can't bless non-reference value
653
654(F) Only hard references may be blessed. This is how Perl "enforces"
655encapsulation of objects. See L<perlobj>.
656
dc57907a
RGS
657=item Can't "break" in a loop topicalizer
658
0d863452 659(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 660a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
661
662=item Can't "break" outside a given block
dc57907a 663
0d863452
RH
664(F) You called C<break>, but you're not inside a C<given> block.
665
6df41af2
GS
666=item Can't call method "%s" on an undefined value
667
668(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
669object reference or package name contains an undefined value. Something
670like this will reproduce the error:
6df41af2
GS
671
672 $BADREF = undef;
673 process $BADREF 1,2,3;
674 $BADREF->process(1,2,3);
675
a0d0e21e
LW
676=item Can't call method "%s" on unblessed reference
677
54310121 678(F) A method call must know in what package it's supposed to run. It
be771a83
GS
679ordinarily finds this out from the object reference you supply, but you
680didn't supply an object reference in this case. A reference isn't an
681object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
682
683=item Can't call method "%s" without a package or object reference
684
685(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
686object reference or package name contains an expression that returns a
687defined value which is neither an object reference nor a package name.
72b5445b
GS
688Something like this will reproduce the error:
689
690 $BADREF = 42;
691 process $BADREF 1,2,3;
692 $BADREF->process(1,2,3);
693
dfe378f1
FC
694=item Can't call mro_isa_changed_in() on anonymous symbol table
695
696(P) Perl got confused as to whether a hash was a plain hash or a
697symbol table hash when trying to update @ISA caches.
698
2bf7e7b2
FC
699=item Can't call mro_method_changed_in() on anonymous symbol table
700
701(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
702not attached to the symbol table.
703
a0d0e21e
LW
704=item Can't chdir to %s
705
f703fc96 706(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
707that you can chdir to, possibly because it doesn't exist.
708
0545a864 709=item Can't check filesystem of script "%s" for nosuid
104d25b7 710
be771a83
GS
711(P) For some reason you can't check the filesystem of the script for
712nosuid.
104d25b7 713
22e74366 714=item Can't coerce %s to %s in %s
a0d0e21e
LW
715
716(F) Certain types of SVs, in particular real symbol table entries
55497cff 717(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
718say things like:
719
720 *foo += 1;
721
722You CAN say
723
724 $foo = *foo;
725 $foo += 1;
726
727but then $foo no longer contains a glob.
728
0d863452 729=item Can't "continue" outside a when block
dc57907a 730
0d863452
RH
731(F) You called C<continue>, but you're not inside a C<when>
732or C<default> block.
733
a0d0e21e
LW
734=item Can't create pipe mailbox
735
be771a83
GS
736(P) An error peculiar to VMS. The process is suffering from exhausted
737quotas or other plumbing problems.
a0d0e21e 738
eb64745e
GS
739=item Can't declare %s in "%s"
740
30c282f6
NC
741(F) Only scalar, array, and hash variables may be declared as "my", "our" or
742"state" variables. They must have ordinary identifiers as names.
a0d0e21e 743
fc7debfb
FC
744=item Can't "default" outside a topicalizer
745
746(F) You have used a C<default> block that is neither inside a
747C<foreach> loop nor a C<given> block. (Note that this error is
748issued on exit from the C<default> block, so you won't get the
749error if you use an explicit C<continue>.)
750
6df41af2
GS
751=item Can't do inplace edit: %s is not a regular file
752
be771a83 753(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 754a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 755
a0d0e21e
LW
756=item Can't do inplace edit on %s: %s
757
be771a83
GS
758(S inplace) The creation of the new file failed for the indicated
759reason.
a0d0e21e 760
54310121 761=item Can't do inplace edit without backup
a0d0e21e 762
be771a83
GS
763(F) You're on a system such as MS-DOS that gets confused if you try
764reading from a deleted (but still opened) file. You have to say
765C<-i.bak>, or some such.
a0d0e21e 766
10f9c03d 767=item Can't do inplace edit: %s would not be unique
a0d0e21e 768
e476b1b5 769(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
770characters and Perl was unable to create a unique filename during
771inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 772
a0d0e21e
LW
773=item Can't do waitpid with flags
774
be771a83
GS
775(F) This machine doesn't have either waitpid() or wait4(), so only
776waitpid() without flags is emulated.
a0d0e21e 777
a0d0e21e
LW
778=item Can't emulate -%s on #! line
779
be771a83
GS
780(F) The #! line specifies a switch that doesn't make sense at this
781point. For example, it'd be kind of silly to put a B<-x> on the #!
782line.
a0d0e21e 783
1109a392
MHM
784=item Can't %s %s-endian %ss on this platform
785
786(F) Your platform's byte-order is neither big-endian nor little-endian,
787or it has a very strange pointer size. Packing and unpacking big- or
788little-endian floating point values and pointers may not be possible.
789See L<perlfunc/pack>.
790
a0d0e21e
LW
791=item Can't exec "%s": %s
792
d1be9408 793(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
794named program for the indicated reason. Typical reasons include: the
795permissions were wrong on the file, the file wasn't found in
796C<$ENV{PATH}>, the executable in question was compiled for another
797architecture, or the #! line in a script points to an interpreter that
798can't be run for similar reasons. (Or maybe your system doesn't support
799#! at all.)
a0d0e21e
LW
800
801=item Can't exec %s
802
be771a83
GS
803(F) Perl was trying to execute the indicated program for you because
804that's what the #! line said. If that's not what you wanted, you may
805need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
806
807=item Can't execute %s
808
be771a83
GS
809(F) You used the B<-S> switch, but the copies of the script to execute
810found in the PATH did not have correct permissions.
2a92aaa0 811
6df41af2 812=item Can't find an opnumber for "%s"
2a92aaa0 813
be771a83
GS
814(F) A string of a form C<CORE::word> was given to prototype(), but there
815is no builtin with the name C<word>.
6df41af2 816
56ca2fc0
JH
817=item Can't find %s character property "%s"
818
819(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 820could not be found. Maybe you misspelled the name of the property?
e1b711da 821See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 822for a complete list of available official properties.
56ca2fc0 823
6df41af2
GS
824=item Can't find label %s
825
be771a83
GS
826(F) You said to goto a label that isn't mentioned anywhere that it's
827possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
828
829=item Can't find %s on PATH
830
be771a83
GS
831(F) You used the B<-S> switch, but the script to execute could not be
832found in the PATH.
a0d0e21e 833
6df41af2 834=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 835
be771a83
GS
836(F) You used the B<-S> switch, but the script to execute could not be
837found in the PATH, or at least not with the correct permissions. The
838script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
839
840=item Can't find string terminator %s anywhere before EOF
841
be771a83
GS
842(F) Perl strings can stretch over multiple lines. This message means
843that the closing delimiter was omitted. Because bracketed quotes count
844nesting levels, the following is missing its final parenthesis:
a0d0e21e 845
fb73857a
PP
846 print q(The character '(' starts a side comment.);
847
97b3d10f 848If you're getting this error from a here-document, you may have
b6b8cb97
FC
849included unseen whitespace before or after your closing tag or there
850may not be a linebreak after it. A good programmer's editor will have
851a way to help you find these characters (or lack of characters). See
852L<perlop> for the full details on here-documents.
a0d0e21e 853
660a4616
ST
854=item Can't find Unicode property definition "%s"
855
5f8ad6b6
FC
856(F) You may have tried to use C<\p> which means a Unicode
857property (for example C<\p{Lu}> matches all uppercase
fa816bf3 858letters). If you did mean to use a Unicode property, see
e1b711da 859L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 860for a complete list of available properties. If you didn't
fa816bf3
FC
861mean to use a Unicode property, escape the C<\p>, either by
862C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 863until C<\E>).
660a4616 864
b3647a36 865=item Can't fork: %s
a0d0e21e 866
be771a83
GS
867(F) A fatal error occurred while trying to fork while opening a
868pipeline.
a0d0e21e 869
b3647a36
SR
870=item Can't fork, trying again in 5 seconds
871
c973c02e 872(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
873after five seconds.
874
748a9306
LW
875=item Can't get filespec - stale stat buffer?
876
be771a83
GS
877(S) A warning peculiar to VMS. This arises because of the difference
878between access checks under VMS and under the Unix model Perl assumes.
879Under VMS, access checks are done by filename, rather than by bits in
880the stat buffer, so that ACLs and other protections can be taken into
881account. Unfortunately, Perl assumes that the stat buffer contains all
882the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 883the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
884the device name and FID present in the stat buffer, but this works only
885if you haven't made a subsequent call to the CRTL stat() routine,
886because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
887appears, the name lookup failed, and the access-checking routine gave up
888and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
889routine knows about the Perl C<stat> operator and file tests, so you
890shouldn't ever see this warning in response to a Perl command; it arises
891only if some internal code takes stat buffers lightly.)
748a9306 892
a0d0e21e
LW
893=item Can't get pipe mailbox device name
894
be771a83
GS
895(P) An error peculiar to VMS. After creating a mailbox to act as a
896pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
897
898=item Can't get SYSGEN parameter value for MAXBUF
899
748a9306
LW
900(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
901mailbox buffers to be, and didn't get an answer.
a0d0e21e 902
6df41af2 903=item Can't "goto" into the middle of a foreach loop
a0d0e21e 904
be771a83
GS
905(F) A "goto" statement was executed to jump into the middle of a foreach
906loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
907
908=item Can't "goto" out of a pseudo block
909
be771a83
GS
910(F) A "goto" statement was executed to jump out of what might look like
911a block, except that it isn't a proper block. This usually occurs if
912you tried to jump out of a sort() block or subroutine, which is a no-no.
913See L<perlfunc/goto>.
a0d0e21e 914
5a25739d
FC
915=item Can't goto subroutine from an eval-%s
916
917(F) The "goto subroutine" call can't be used to jump out of an eval
918"string" or block.
919
9850bf21 920=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 921
9850bf21
RH
922(F) The "goto subroutine" call can't be used to jump out of the
923comparison sub for a sort(), or from a similar callback (such
924as the reduce() function in List::Util).
925
6df41af2
GS
926=item Can't goto subroutine outside a subroutine
927
be771a83
GS
928(F) The deeply magical "goto subroutine" call can only replace one
929subroutine call for another. It can't manufacture one out of whole
930cloth. In general you should be calling it out of only an AUTOLOAD
931routine anyway. See L<perlfunc/goto>.
6df41af2 932
0b5b802d
GS
933=item Can't ignore signal CHLD, forcing to default
934
be771a83
GS
935(W signal) Perl has detected that it is being run with the SIGCHLD
936signal (sometimes known as SIGCLD) disabled. Since disabling this
937signal will interfere with proper determination of exit status of child
938processes, Perl has reset the signal to its default value. This
939situation typically indicates that the parent program under which Perl
940may be running (e.g. cron) is being very careless.
0b5b802d 941
e2c0f81f
DG
942=item Can't kill a non-numeric process ID
943
944(F) Process identifiers must be (signed) integers. It is a fatal error to
945attempt to kill() an undefined, empty-string or otherwise non-numeric
946process identifier.
947
6df41af2 948=item Can't "last" outside a loop block
4633a7c4 949
6df41af2 950(F) A "last" statement was executed to break out of the current block,
be771a83
GS
951except that there's this itty bitty problem called there isn't a current
952block. Note that an "if" or "else" block doesn't count as a "loopish"
953block, as doesn't a block given to sort(), map() or grep(). You can
954usually double the curlies to get the same effect though, because the
955inner curlies will be considered a block that loops once. See
956L<perlfunc/last>.
4633a7c4 957
2c7d6b9c
RGS
958=item Can't linearize anonymous symbol table
959
960(F) Perl tried to calculate the method resolution order (MRO) of a
961package, but failed because the package stash has no name.
962
b8170e59
JB
963=item Can't load '%s' for module %s
964
6903afa2
FC
965(F) The module you tried to load failed to load a dynamic extension.
966This may either mean that you upgraded your version of perl to one
967that is incompatible with your old dynamic extensions (which is known
968to happen between major versions of perl), or (more likely) that your
969dynamic extension was built against an older version of the library
970that is installed on your system. You may need to rebuild your old
971dynamic extensions.
b8170e59 972
748a9306
LW
973=item Can't localize lexical variable %s
974
2ba9eb46 975(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
976lexical variable using "my" or "state". This is not allowed. If you
977want to localize a package variable of the same name, qualify it with
978the package name.
748a9306 979
6df41af2 980=item Can't localize through a reference
4727527e 981
6df41af2
GS
982(F) You said something like C<local $$ref>, which Perl can't currently
983handle, because when it goes to restore the old value of whatever $ref
be771a83 984pointed to after the scope of the local() is finished, it can't be sure
64977eb6 985that $ref will still be a reference.
4727527e 986
ea071790 987=item Can't locate %s
ec889f3a 988
fa816bf3
FC
989(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
990Perl looks for the file in all the locations mentioned in @INC, unless
991the file name included the full path to the file. Perhaps you need
992to set the PERL5LIB or PERL5OPT environment variable to say where the
993extra library is, or maybe the script needs to add the library name
be771a83
GS
994to @INC. Or maybe you just misspelled the name of the file. See
995L<perlfunc/require> and L<lib>.
a0d0e21e 996
6df41af2
GS
997=item Can't locate auto/%s.al in @INC
998
be771a83
GS
999(F) A function (or method) was called in a package which allows
1000autoload, but there is no function to autoload. Most probable causes
1001are a misprint in a function/method name or a failure to C<AutoSplit>
1002the file, say, by doing C<make install>.
6df41af2 1003
b8170e59
JB
1004=item Can't locate loadable object for module %s in @INC
1005
1006(F) The module you loaded is trying to load an external library, like
d70d8e57 1007for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1008unable to locate this library. See L<DynaLoader>.
1009
a0d0e21e
LW
1010=item Can't locate object method "%s" via package "%s"
1011
1012(F) You called a method correctly, and it correctly indicated a package
1013functioning as a class, but that package doesn't define that particular
2ba9eb46 1014method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1015
8af56b9d
FC
1016=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1017to load "%s"?)
1018
1019(F) You called a method on a class that did not exist, and the method
1020could not be found in UNIVERSAL. This often means that a method
1021requires a package that has not been loaded.
1022
a0d0e21e
LW
1023=item Can't locate package %s for @%s::ISA
1024
be771a83
GS
1025(W syntax) The @ISA array contained the name of another package that
1026doesn't seem to exist.
a0d0e21e 1027
2f7da168
RK
1028=item Can't locate PerlIO%s
1029
1030(F) You tried to use in open() a PerlIO layer that does not exist,
1031e.g. open(FH, ">:nosuchlayer", "somefile").
1032
f4ad53f4 1033=item Can't make list assignment to %ENV on this system
3e3baf6d 1034
be771a83
GS
1035(F) List assignment to %ENV is not supported on some systems, notably
1036VMS.
3e3baf6d 1037
cd40cd58
NC
1038=item Can't make loaded symbols global on this platform while loading %s
1039
ff9c1ae8 1040(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1041that symbols from the stated file are made available globally within the
1042process, but that functionality is not available on this platform. Whilst
1043the module likely will still work, this may prevent the perl interpreter
1044from loading other XS-based extensions which need to link directly to
1045functions defined in the C or XS code in the stated file.
1046
a0d0e21e
LW
1047=item Can't modify %s in %s
1048
be771a83
GS
1049(F) You aren't allowed to assign to the item indicated, or otherwise try
1050to change it, such as with an auto-increment.
a0d0e21e 1051
54310121 1052=item Can't modify nonexistent substring
a0d0e21e
LW
1053
1054(P) The internal routine that does assignment to a substr() was handed
1055a NULL.
1056
6df41af2
GS
1057=item Can't modify non-lvalue subroutine call
1058
1059(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1060such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1061
cf6e1fa1
FC
1062=item Can't modify reference to %s in %s assignment
1063
1064(F) Only a limited number of constructs can be used as the argument to a
1065reference constructor on the left-hand side of an assignment, and what
1066you used was not one of them. See L<perlref/Assigning to References>.
1067
1068=item Can't modify reference to localized parenthesized array in list
1069assignment
1070
1071(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1072it is not clear exactly what it should do. If you meant to make @array
1073refer to some other array, use C<\@array = \@other_array>. If you want to
1074make the elements of @array aliases of the scalars referenced on the
1075right-hand side, use C<\(@array) = @scalar_refs>.
1076
1077=item Can't modify reference to parenthesized hash in list assignment
1078
1079(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1080refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1081make the elements of %hash into aliases of the scalars referenced on the
1082right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1083
5f05dabc 1084=item Can't msgrcv to read-only var
a0d0e21e 1085
5f05dabc 1086(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1087buffer.
1088
6df41af2
GS
1089=item Can't "next" outside a loop block
1090
1091(F) A "next" statement was executed to reiterate the current block, but
1092there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1093count as a "loopish" block, as doesn't a block given to sort(), map() or
1094grep(). You can usually double the curlies to get the same effect
1095though, because the inner curlies will be considered a block that loops
1096once. See L<perlfunc/next>.
6df41af2 1097
a0d0e21e
LW
1098=item Can't open %s: %s
1099
c47ff5f1 1100(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1101filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1102switches, or explicitly, failed for the indicated reason. Usually
1103this is because you don't have read permission for a file which
1104you named on the command line.
1105
1106(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1107your operating system's equivalent) could not be opened.
a0d0e21e 1108
9a869a14
RGS
1109=item Can't open a reference
1110
1111(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1112using the 3-arg open() syntax:
9a869a14
RGS
1113
1114 open FH, '>', $ref;
1115
1116but your version of perl is compiled without perlio, and this form of
1117open is not supported.
1118
a0d0e21e
LW
1119=item Can't open bidirectional pipe
1120
be771a83
GS
1121(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1122You can try any of several modules in the Perl library to do this, such
1123as IPC::Open2. Alternately, direct the pipe's output to a file using
1124">", and then read it in under a different file handle.
a0d0e21e 1125
748a9306
LW
1126=item Can't open error file %s as stderr
1127
be771a83
GS
1128(F) An error peculiar to VMS. Perl does its own command line
1129redirection, and couldn't open the file specified after '2>' or '2>>' on
1130the command line for writing.
748a9306
LW
1131
1132=item Can't open input file %s as stdin
1133
be771a83
GS
1134(F) An error peculiar to VMS. Perl does its own command line
1135redirection, and couldn't open the file specified after '<' on the
1136command line for reading.
748a9306
LW
1137
1138=item Can't open output file %s as stdout
1139
be771a83
GS
1140(F) An error peculiar to VMS. Perl does its own command line
1141redirection, and couldn't open the file specified after '>' or '>>' on
1142the command line for writing.
748a9306
LW
1143
1144=item Can't open output pipe (name: %s)
1145
be771a83
GS
1146(P) An error peculiar to VMS. Perl does its own command line
1147redirection, and couldn't open the pipe into which to send data destined
1148for stdout.
748a9306 1149
3b1cf97d 1150=item Can't open perl script "%s": %s
a0d0e21e
LW
1151
1152(F) The script you specified can't be opened for the indicated reason.
1153
fa3aa65a
JC
1154If you're debugging a script that uses #!, and normally relies on the
1155shell's $PATH search, the -S option causes perl to do that search, so
1156you don't have to type the path or C<`which $scriptname`>.
1157
6df41af2
GS
1158=item Can't read CRTL environ
1159
1160(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1161from the CRTL's internal environment array and discovered the array was
1162missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1163or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1164searched.
6df41af2 1165
6df41af2
GS
1166=item Can't "redo" outside a loop block
1167
1168(F) A "redo" statement was executed to restart the current block, but
1169there isn't a current block. Note that an "if" or "else" block doesn't
1170count as a "loopish" block, as doesn't a block given to sort(), map()
1171or grep(). You can usually double the curlies to get the same effect
1172though, because the inner curlies will be considered a block that
1173loops once. See L<perlfunc/redo>.
1174
64977eb6 1175=item Can't remove %s: %s, skipping file
10f9c03d 1176
be771a83
GS
1177(S inplace) You requested an inplace edit without creating a backup
1178file. Perl was unable to remove the original file to replace it with
1179the modified file. The file was left unmodified.
10f9c03d 1180
a0d0e21e
LW
1181=item Can't rename %s to %s: %s, skipping file
1182
e476b1b5 1183(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1184probably because you don't have write permission to the directory.
a0d0e21e 1185
748a9306
LW
1186=item Can't reopen input pipe (name: %s) in binary mode
1187
be771a83
GS
1188(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1189to reopen it to accept binary data. Alas, it failed.
748a9306 1190
9415f659
KW
1191=item Can't represent character for Ox%X on this platform
1192
1193(F) There is a hard limit to how big a character code point can be due
1194to the fundamental properties of UTF-8, especially on EBCDIC
1195platforms. The given code point exceeds that. The only work-around is
1196to not use such a large code point.
1197
4f12ec0e
FC
1198=item Can't reset %ENV on this system
1199
1200(F) You called C<reset('E')> or similar, which tried to reset
1201all variables in the current package beginning with "E". In
1202the main package, that includes %ENV. Resetting %ENV is not
1203supported on some systems, notably VMS.
1204
fe13d51d 1205=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1206
1fa582fa
FC
1207(F)(P) Error resolving overloading specified by a method name (as
1208opposed to a subroutine reference): no such method callable via the
1209package. If the method name is C<???>, this is an internal error.
6df41af2 1210
cd06dffe
GS
1211=item Can't return %s from lvalue subroutine
1212
be771a83
GS
1213(F) Perl detected an attempt to return illegal lvalues (such as
1214temporary or readonly values) from a subroutine used as an lvalue. This
1215is not allowed.
cd06dffe 1216
96ebfdd7
RK
1217=item Can't return outside a subroutine
1218
1219(F) The return statement was executed in mainline code, that is, where
1220there was no subroutine call to return out of. See L<perlsub>.
1221
78f9721b
SM
1222=item Can't return %s to lvalue scalar context
1223
6903afa2
FC
1224(F) You tried to return a complete array or hash from an lvalue
1225subroutine, but you called the subroutine in a way that made Perl
1226think you meant to return only one value. You probably meant to
1227write parentheses around the call to the subroutine, which tell
1228Perl that the call should be in list context.
78f9721b 1229
a0d0e21e
LW
1230=item Can't stat script "%s"
1231
be771a83
GS
1232(P) For some reason you can't fstat() the script even though you have it
1233open already. Bizarre.
a0d0e21e 1234
a0d0e21e
LW
1235=item Can't take log of %g
1236
fb73857a 1237(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1238negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1239standard with Perl, though, if you really want to do that for the
1240negative numbers.
a0d0e21e
LW
1241
1242=item Can't take sqrt of %g
1243
1244(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1245negative number. There's a Math::Complex package that comes standard
1246with Perl, though, if you really want to do that.
a0d0e21e
LW
1247
1248=item Can't undef active subroutine
1249
1250(F) You can't undefine a routine that's currently running. You can,
1251however, redefine it while it's running, and you can even undef the
1252redefined subroutine while the old routine is running. Go figure.
1253
c81225bc 1254=item Can't upgrade %s (%d) to %d
a0d0e21e 1255
be771a83
GS
1256(P) The internal sv_upgrade routine adds "members" to an SV, making it
1257into a more specialized kind of SV. The top several SV types are so
1258specialized, however, that they cannot be interconverted. This message
1259indicates that such a conversion was attempted.
a0d0e21e 1260
6651ba0b
FC
1261=item Can't use '%c' after -mname
1262
1263(F) You tried to call perl with the B<-m> switch, but you put something
1264other than "=" after the module name.
1265
1f1ec7b5
KW
1266=item Can't use a hash as a reference
1267
1268(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1269C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1270<= 5.22.0 used to allow this syntax, but shouldn't
1271have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1272
1273=item Can't use an array as a reference
1274
1275(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1276C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1277used to allow this syntax, but shouldn't have. This
1278was deprecated in perl 5.6.1.
1f1ec7b5 1279
1db89ea5
BS
1280=item Can't use anonymous symbol table for method lookup
1281
e27ad1f2 1282(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1283table that doesn't have a name. Symbol tables can become anonymous
1284for example by undefining stashes: C<undef %Some::Package::>.
1285
96ebfdd7
RK
1286=item Can't use an undefined value as %s reference
1287
1288(F) A value used as either a hard reference or a symbolic reference must
1289be a defined value. This helps to delurk some insidious errors.
1290
6df41af2
GS
1291=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1292
be771a83
GS
1293(F) Only hard references are allowed by "strict refs". Symbolic
1294references are disallowed. See L<perlref>.
6df41af2 1295
90b75b61 1296=item Can't use %! because Errno.pm is not available
1d2dff63 1297
20561843 1298(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1299Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1300provide symbolic names for C<$!> errno values.
1301
1109a392
MHM
1302=item Can't use both '<' and '>' after type '%c' in %s
1303
1304(F) A type cannot be forced to have both big-endian and little-endian
1305byte-order at the same time, so this combination of modifiers is not
1306allowed. See L<perlfunc/pack>.
1307
e35475de
KW
1308=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1309
1310(F) defined() is not useful on arrays because it
1311checks for an undefined I<scalar> value. If you want to see if the
1312array is empty, just use C<if (@array) { # not empty }> for example.
1313
1314=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1315
1316(F) C<defined()> is not usually right on hashes.
1317
1318Although C<defined %hash> is false on a plain not-yet-used hash, it
1319becomes true in several non-obvious circumstances, including iterators,
1320weak references, stash names, even remaining true after C<undef %hash>.
1321These things make C<defined %hash> fairly useless in practice, so it now
1322generates a fatal error.
1323
1324If a check for non-empty is what you wanted then just put it in boolean
1325context (see L<perldata/Scalar values>):
1326
1327 if (%hash) {
1328 # not empty
1329 }
1330
1331If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1332variable exists then that's never really been reliable, and isn't
1333a good way to enquire about the features of a package, or whether
1334it's loaded, etc.
1335
6df41af2
GS
1336=item Can't use %s for loop variable
1337
be771a83
GS
1338(F) Only a simple scalar variable may be used as a loop variable on a
1339foreach.
6df41af2 1340
aab6a793 1341=item Can't use global %s in "%s"
6df41af2 1342
be771a83
GS
1343(F) You tried to declare a magical variable as a lexical variable. This
1344is not allowed, because the magic can be tied to only one location
1345(namely the global variable) and it would be incredibly confusing to
1346have variables in your program that looked like magical variables but
6df41af2
GS
1347weren't.
1348
6d3b25aa
RGS
1349=item Can't use '%c' in a group with different byte-order in %s
1350
1351(F) You attempted to force a different byte-order on a type
1352that is already inside a group with a byte-order modifier.
1353For example you cannot force little-endianness on a type that
1354is inside a big-endian group.
1355
c07a80fd
PP
1356=item Can't use "my %s" in sort comparison
1357
1358(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1359You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1360and the variable had earlier been declared as a lexical variable.
1361Either qualify the sort variable with the package name, or rename the
1362lexical variable.
1363
a0d0e21e
LW
1364=item Can't use %s ref as %s ref
1365
1366(F) You've mixed up your reference types. You have to dereference a
1367reference of the type needed. You can use the ref() function to
1368test the type of the reference, if need be.
1369
748a9306 1370=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1371
5e634d20
FC
1372=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1373
b41bf23f
FC
1374(F) You've told Perl to dereference a string, something which
1375C<use strict> blocks to prevent it happening accidentally. See
1376L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1377in a double-quoted string immediately before interpolating a variable,
1378for example in C<"user @$twitter_id">, which says to treat the contents
1379of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1380symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1381
748a9306
LW
1382=item Can't use subscript on %s
1383
1384(F) The compiler tried to interpret a bracketed expression as a
1385subscript. But to the left of the brackets was an expression that
209e7cf1 1386didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1387
6df41af2
GS
1388=item Can't use \%c to mean $%c in expression
1389
75b44862
GS
1390(W syntax) In an ordinary expression, backslash is a unary operator that
1391creates a reference to its argument. The use of backslash to indicate a
1392backreference to a matched substring is valid only as part of a regular
be771a83
GS
1393expression pattern. Trying to do this in ordinary Perl code produces a
1394value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1395instead.
6df41af2 1396
810b8aa5
GS
1397=item Can't weaken a nonreference
1398
1399(F) You attempted to weaken something that was not a reference. Only
1400references can be weakened.
1401
fc7debfb
FC
1402=item Can't "when" outside a topicalizer
1403
1404(F) You have used a when() block that is neither inside a C<foreach>
1405loop nor a C<given> block. (Note that this error is issued on exit
1406from the C<when> block, so you won't get the error if the match fails,
1407or if you use an explicit C<continue>.)
1408
5f05dabc 1409=item Can't x= to read-only value
a0d0e21e 1410
be771a83
GS
1411(F) You tried to repeat a constant value (often the undefined value)
1412with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1413Perhaps you need to copy the value to a temporary, and repeat that.
1414
a04e6aad 1415=item Character following "\c" must be printable ASCII
f9d13529 1416
7357bd17 1417(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1418
727b6379 1419Note that ASCII characters that don't map to control characters are
7357bd17 1420discouraged, and will generate the warning (when enabled)
727b6379 1421L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1422
f337b084 1423=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1424
1425(W pack) You said
1426
1427 pack("C", $x)
1428
1429where $x is either less than 0 or more than 255; the C<"C"> format is
1430only for encoding native operating system characters (ASCII, EBCDIC,
1431and so on) and not for Unicode characters, so Perl behaved as if you meant
1432
1433 pack("C", $x & 255)
1434
1435If you actually want to pack Unicode codepoints, use the C<"U"> format
1436instead.
1437
f337b084 1438=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1439
1440(W pack) You said
1441
1442 pack("c", $x)
1443
1444where $x is either less than -128 or more than 127; the C<"c"> format
1445is only for encoding native operating system characters (ASCII, EBCDIC,
1446and so on) and not for Unicode characters, so Perl behaved as if you meant
1447
1448 pack("c", $x & 255);
1449
1450If you actually want to pack Unicode codepoints, use the C<"U"> format
1451instead.
1452
f337b084
TH
1453=item Character in '%c' format wrapped in unpack
1454
1455(W unpack) You tried something like
1456
1457 unpack("H", "\x{2a1}")
1458
1a147d38 1459where the format expects to process a byte (a character with a value
6903afa2
FC
1460below 256), but a higher value was provided instead. Perl uses the
1461value modulus 256 instead, as if you had provided:
f337b084
TH
1462
1463 unpack("H", "\x{a1}")
1464
5a25739d
FC
1465=item Character in 'W' format wrapped in pack
1466
1467(W pack) You said
1468
1469 pack("U0W", $x)
1470
1471where $x is either less than 0 or more than 255. However, C<U0>-mode
1472expects all values to fall in the interval [0, 255], so Perl behaved
1473as if you meant:
1474
1475 pack("U0W", $x & 255)
1476
f337b084
TH
1477=item Character(s) in '%c' format wrapped in pack
1478
1479(W pack) You tried something like
1480
1481 pack("u", "\x{1f3}b")
1482
1a147d38 1483where the format expects to process a sequence of bytes (character with a
6903afa2 1484value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1485uses the character values modulus 256 instead, as if you had provided:
1486
1487 pack("u", "\x{f3}b")
1488
1489=item Character(s) in '%c' format wrapped in unpack
1490
1491(W unpack) You tried something like
1492
1493 unpack("s", "\x{1f3}b")
1494
1a147d38 1495where the format expects to process a sequence of bytes (character with a
6903afa2 1496value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1497uses the character values modulus 256 instead, as if you had provided:
1498
1499 unpack("s", "\x{f3}b")
1500
f51551f7
FC
1501=item charnames alias definitions may not contain a sequence of multiple spaces
1502
1503(F) You defined a character name which had multiple space characters
1504in a row. Change them to single spaces. Usually these names are
1505defined in the C<:alias> import argument to C<use charnames>, but they
1506could be defined by a translator installed into C<$^H{charnames}>. See
1507L<charnames/CUSTOM ALIASES>.
1508
1509=item charnames alias definitions may not contain trailing white-space
1510
1511(F) You defined a character name which ended in a space
1512character. Remove the trailing space(s). Usually these names are
1513defined in the C<:alias> import argument to C<use charnames>, but they
1514could be defined by a translator installed into C<$^H{charnames}>.
1515See L<charnames/CUSTOM ALIASES>.
1516
1517=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1518
1519(D deprecated, regexp) The \C character class is deprecated, and will
1520become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1521v5.24). This construct allows you to match a single byte of what makes
1522up a multi-byte single UTF8 character, and breaks encapsulation. It is
1523currently also very buggy. If you really need to process the individual
f51551f7
FC
1524bytes, you probably want to convert your string to one where each
1525underlying byte is stored as a character, with utf8::encode().
1526
f866a7cd
FC
1527=item "\c%c" is more clearly written simply as "%s"
1528
1529(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1530non-printable characters. You used it for a printable one, which
1531is better written as simply itself, perhaps preceded by a backslash
1532for non-word characters. Doing it the way you did is not portable
1533between ASCII and EBCDIC platforms.
f866a7cd 1534
6651ba0b
FC
1535=item Cloning substitution context is unimplemented
1536
1537(F) Creating a new thread inside the C<s///> operator is not supported.
1538
abc7ecad
SP
1539=item closedir() attempted on invalid dirhandle %s
1540
1541(W io) The dirhandle you tried to close is either closed or not really
1542a dirhandle. Check your control flow.
1543
5a25739d
FC
1544=item close() on unopened filehandle %s
1545
1546(W unopened) You tried to close a filehandle that was never opened.
1547
541ed3a9
FC
1548=item Closure prototype called
1549
1550(F) If a closure has attributes, the subroutine passed to an attribute
1551handler is the prototype that is cloned when a new closure is created.
1552This subroutine cannot be called.
1553
49704364
LW
1554=item Code missing after '/'
1555
6903afa2
FC
1556(F) You had a (sub-)template that ends with a '/'. There must be
1557another template code following the slash. See L<perlfunc/pack>.
49704364 1558
5a25739d
FC
1559=item Code point 0x%X is not Unicode, may not be portable
1560
2d88a86a 1561(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1562of U+10FFFF.
1563
1564Perl allows strings to contain a superset of Unicode code points, up
1565to the limit of what is storable in an unsigned integer on your system,
1566but these may not be accepted by other languages/systems. At one time,
1567it was legal in some standards to have code points up to 0x7FFF_FFFF,
1568but not higher. Code points above 0xFFFF_FFFF require larger than a
156932 bit word.
0876b9a0 1570
6df41af2
GS
1571=item %s: Command not found
1572
a892b81a 1573(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1574instead of Perl. Check the #! line, or manually feed your script into
1575Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1576
1577 #!/usr/bin/perl -w
6df41af2 1578
7a2e2cd6
PP
1579=item Compilation failed in require
1580
1581(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1582Perl uses this generic message when none of the errors that it
1583encountered were severe enough to halt compilation immediately.
7a2e2cd6 1584
c3464db5
DD
1585=item Complex regular subexpression recursion limit (%d) exceeded
1586
be771a83
GS
1587(W regexp) The regular expression engine uses recursion in complex
1588situations where back-tracking is required. Recursion depth is limited
1589to 32766, or perhaps less in architectures where the stack cannot grow
1590arbitrarily. ("Simple" and "medium" situations are handled without
1591recursion and are not subject to a limit.) Try shortening the string
1592under examination; looping in Perl code (e.g. with C<while>) rather than
1593in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1594that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1595on I<Mastering Regular Expressions>.)
c3464db5 1596
69282e91 1597=item connect() on closed socket %s
a0d0e21e 1598
be771a83
GS
1599(W closed) You tried to do a connect on a closed socket. Did you forget
1600to check the return value of your socket() call? See
1601L<perlfunc/connect>.
a0d0e21e 1602
e21e7c6a
FC
1603=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1604
1605(F) The subroutine registered to handle constant overloading
1606(see L<overload>) or a custom charnames handler (see
1607L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1608
1609=item Constant(%s): $^H{%s} is not defined
1610
1611(F) The parser found inconsistencies while attempting to define an
1612overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1613L<overload> pragma?
e21e7c6a 1614
779c5bc9
GS
1615=item Constant is not %s reference
1616
1617(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1618is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1619The message indicates the type of reference that was expected. This
be771a83 1620usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1621See L<perlsub/"Constant Functions"> and L<constant>.
1622
4cee8e80
CS
1623=item Constant subroutine %s redefined
1624
aeb94125
FC
1625(W redefine)(S) You redefined a subroutine which had previously
1626been eligible for inlining. See L<perlsub/"Constant Functions">
1627for commentary and workarounds.
4cee8e80 1628
9607fc9c
PP
1629=item Constant subroutine %s undefined
1630
be771a83
GS
1631(W misc) You undefined a subroutine which had previously been eligible
1632for inlining. See L<perlsub/"Constant Functions"> for commentary and
1633workarounds.
9607fc9c 1634
5a25739d
FC
1635=item Constant(%s) unknown
1636
1637(F) The parser found inconsistencies either while attempting
1638to define an overloaded constant, or when trying to find the
1639character name specified in the C<\N{...}> escape. Perhaps you
1640forgot to load the corresponding L<overload> pragma?.
1641
e7ea3e70
IZ
1642=item Copy method did not return a reference
1643
6903afa2 1644(F) The method which overloads "=" is buggy. See
13a2d996 1645L<overload/Copy Constructor>.
e7ea3e70 1646
4aaa4757
FC
1647=item &CORE::%s cannot be called directly
1648
1649(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1650with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1651in this package cannot yet be called that way, but must be
1652called as barewords. Something like this will work:
1653
1654 BEGIN { *shove = \&CORE::push; }
1655 shove @array, 1,2,3; # pushes on to @array
1656
6798c92b
GS
1657=item CORE::%s is not a keyword
1658
1659(F) The CORE:: namespace is reserved for Perl keywords.
1660
675fa9ff
FC
1661=item Corrupted regexp opcode %d > %d
1662
1663(P) This is either an error in Perl, or, if you're using
1664one, your L<custom regular expression engine|perlreapi>. If not the
1665latter, report the problem through the L<perlbug> utility.
1666
a0d0e21e
LW
1667=item corrupted regexp pointers
1668
1669(P) The regular expression engine got confused by what the regular
1670expression compiler gave it.
1671
1672=item corrupted regexp program
1673
be771a83
GS
1674(P) The regular expression engine got passed a regexp program without a
1675valid magic number.
a0d0e21e 1676
de42a5a9 1677=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1678
1679(P) The malloc package that comes with Perl had an internal failure.
1680
49704364
LW
1681=item Count after length/code in unpack
1682
1683(F) You had an unpack template indicating a counted-length string, but
1684you have also specified an explicit size for the string. See
1685L<perlfunc/pack>.
1686
f2cccb4c
KW
1687=for comment
1688The following are used in lib/diagnostics.t for testing two =items that
1689share the same description. Changes here need to be propagated to there
1690
6651ba0b
FC
1691=item Deep recursion on anonymous subroutine
1692
a0d0e21e
LW
1693=item Deep recursion on subroutine "%s"
1694
be771a83
GS
1695(W recursion) This subroutine has called itself (directly or indirectly)
1696100 times more than it has returned. This probably indicates an
1697infinite recursion, unless you're writing strange benchmark programs, in
1698which case it indicates something else.
a0d0e21e 1699
aad1d01f
NC
1700This threshold can be changed from 100, by recompiling the F<perl> binary,
1701setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1702
e0e4a6e3
FC
1703=item (?(DEFINE)....) does not allow branches in regex; marked by
1704S<<-- HERE> in m/%s/
bcb95744 1705
6903afa2 1706(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1707most likely cause of this error is that you left out a parenthesis inside
1708of the C<....> part.
1709
9e3ec65c 1710The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1711discovered.
1712
62658f4d
PM
1713=item %s defines neither package nor VERSION--version check failed
1714
1715(F) You said something like "use Module 42" but in the Module file
1716there are neither package declarations nor a C<$VERSION>.
1717
36447869
FC
1718=item delete argument is index/value array slice, use array slice
1719
1720(F) You used index/value array slice syntax (C<%array[...]>) as
1721the argument to C<delete>. You probably meant C<@array[...]> with
1722an @ symbol instead.
1723
1724=item delete argument is key/value hash slice, use hash slice
1725
1726(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1727C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1728
0ffcbc25
FC
1729=item delete argument is not a HASH or ARRAY element or slice
1730
4a0af295 1731(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1732such as:
1733
1734 $foo{$bar}
1735 $ref->{"susie"}[12]
1736
1737or a hash or array slice, such as:
1738
1739 @foo[$bar, $baz, $xyzzy]
1740 @{$ref->[12]}{"susie", "queue"}
1741
fc36a67e
PP
1742=item Delimiter for here document is too long
1743
be771a83
GS
1744(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1745long for Perl to handle. You have to be seriously twisted to write code
1746that triggers this error.
fc36a67e 1747
6d3b25aa
RGS
1748=item Deprecated use of my() in false conditional
1749
fa816bf3
FC
1750(D deprecated) You used a declaration similar to C<my $x if 0>. There
1751has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1752not to be cleared at scope exit when its declaration includes a false
6903afa2 1753conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1754static variable. Since we intend to fix this bug, we don't want people
6903afa2 1755relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1756declaring the variable in a separate block outside the function, eg
36fb85f3 1757
6d3b25aa
RGS
1758 sub f { my $x if 0; return $x++ }
1759
1760becomes
1761
1762 { my $x; sub f { return $x++ } }
1763
ea9d9ebc 1764Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1765lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1766
1767 sub f { state $x; return $x++ }
1768
500ab966
RGS
1769=item DESTROY created new reference to dead object '%s'
1770
1771(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1772just being DESTROYed. Perl is confused, and prefers to abort rather
1773than to create a dangling reference.
500ab966 1774
3cdd684c
TP
1775=item Did not produce a valid header
1776
1777See Server error.
1778
6df41af2
GS
1779=item %s did not return a true value
1780
1781(F) A required (or used) file must return a true value to indicate that
1782it compiled correctly and ran its initialization code correctly. It's
1783traditional to end such a file with a "1;", though any true value would
1784do. See L<perlfunc/require>.
1785
cc507455 1786=item (Did you mean &%s instead?)
4633a7c4 1787
413ff9f6
FC
1788(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1789some such.
4633a7c4 1790
cc507455 1791=item (Did you mean "local" instead of "our"?)
33633739 1792
be771a83
GS
1793(W misc) Remember that "our" does not localize the declared global
1794variable. You have declared it again in the same lexical scope, which
1795seems superfluous.
33633739 1796
cc507455 1797=item (Did you mean $ or @ instead of %?)
a0d0e21e 1798
be771a83
GS
1799(W) You probably said %hash{$key} when you meant $hash{$key} or
1800@hash{@keys}. On the other hand, maybe you just meant %hash and got
1801carried away.
748a9306 1802
7e1af8bc 1803=item Died
5f05dabc
PP
1804
1805(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1806you called it with no args and C<$@> was empty.
5f05dabc 1807
3cdd684c
TP
1808=item Document contains no data
1809
1810See Server error.
1811
62658f4d
PM
1812=item %s does not define %s::VERSION--version check failed
1813
1814(F) You said something like "use Module 42" but the Module did not
943fc58e 1815define a C<$VERSION>.
62658f4d 1816
49704364
LW
1817=item '/' does not take a repeat count
1818
1819(F) You cannot put a repeat count of any kind right after the '/' code.
1820See L<perlfunc/pack>.
1821
95cb0d72
FC
1822=item Don't know how to get file name
1823
1824(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1825somehow called on another platform. This should not happen.
1826
4021c788 1827=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1828
1829(P) The internal handling of magical variables has been cursed.
1830
1831=item do_study: out of memory
1832
1833(P) This should have been caught by safemalloc() instead.
1834
6df41af2
GS
1835=item (Do you need to predeclare %s?)
1836
56da5a46
RGS
1837(S syntax) This is an educated guess made in conjunction with the message
1838"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1839name is being referenced that hasn't been declared yet. This may be
1840because of ordering problems in your file, or because of a missing
be771a83
GS
1841"sub", "package", "require", or "use" statement. If you're referencing
1842something that isn't defined yet, you don't actually have to define the
1843subroutine or package before the current location. You can use an empty
1844"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1845
ac206dc8
RGS
1846=item dump() better written as CORE::dump()
1847
1848(W misc) You used the obsolescent C<dump()> built-in function, without fully
1849qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1850
84d78eb7
YO
1851=item dump is not supported
1852
1853(F) Your machine doesn't support dump/undump.
1854
a0d0e21e
LW
1855=item Duplicate free() ignored
1856
be771a83
GS
1857(S malloc) An internal routine called free() on something that had
1858already been freed.
a0d0e21e 1859
1109a392
MHM
1860=item Duplicate modifier '%c' after '%c' in %s
1861
35f0cd76
FC
1862(W unpack) You have applied the same modifier more than once after a
1863type in a pack template. See L<perlfunc/pack>.
1109a392 1864
0953b66b
FC
1865=item each on reference is experimental
1866
0773cb3e
FC
1867(S experimental::autoderef) C<each> with a scalar argument is experimental
1868and may change or be removed in a future Perl version. If you want to
1869take the risk of using this feature, simply disable this warning:
0953b66b 1870
d401967c 1871 no warnings "experimental::autoderef";
0953b66b 1872
4633a7c4
LW
1873=item elseif should be elsif
1874
fa816bf3
FC
1875(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1876it's ugly. Your code will be interpreted as an attempt to call a method
1877named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1878unlikely to be what you want.
1879
e0e4a6e3 1880=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1881
af6f566e 1882(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1883described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1884a regular expression without specifying the property name.
ab13f0c7 1885
85ab1d1d 1886=item entering effective %s failed
5ff3f7a4 1887
85ab1d1d 1888(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1889effective uids or gids failed.
1890
c038024b
RGS
1891=item %ENV is aliased to %s
1892
1893(F) You're running under taint mode, and the C<%ENV> variable has been
1894aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1895program's environment. This is potentially insecure.
c038024b 1896
748a9306
LW
1897=item Error converting file specification %s
1898
5f05dabc 1899(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1900specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1901single form when it must operate on them directly. Either you've passed
1902an invalid file specification to Perl, or you've found a case the
1903conversion routines don't handle. Drat.
748a9306 1904
ad19ef22 1905=item Eval-group in insecure regular expression
e4d48cc9 1906
be771a83
GS
1907(F) Perl detected tainted data when trying to compile a regular
1908expression that contains the C<(?{ ... })> zero-width assertion, which
1909is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1910
ad19ef22 1911=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1912
be771a83
GS
1913(F) Perl tried to compile a regular expression containing the
1914C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1915pattern contains interpolated values. Since that is a security risk,
1916it is not allowed. If you insist, you may still do this by using the
1917C<re 'eval'> pragma or by explicitly building the pattern from an
1918interpolated string at run time and using that in an eval(). See
1919L<perlre/(?{ code })>.
e4d48cc9 1920
ad19ef22 1921=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1922
be771a83
GS
1923(F) A regular expression contained the C<(?{ ... })> zero-width
1924assertion, but that construct is only allowed when the C<use re 'eval'>
1925pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1926
e0e4a6e3
FC
1927=item EVAL without pos change exceeded limit in regex; marked by
1928S<<-- HERE> in m/%s/
1a147d38
YO
1929
1930(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1931any text. Restructure the pattern so that text is consumed.
1a147d38 1932
9e3ec65c 1933The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1934discovered.
1935
fc36a67e
PP
1936=item Excessively long <> operator
1937
1938(F) The contents of a <> operator may not exceed the maximum size of a
1939Perl identifier. If you're just trying to glob a long list of
1940filenames, try using the glob() operator, or put the filenames into a
1941variable and glob that.
1942
ed9aa3b7
SG
1943=item exec? I'm not *that* kind of operating system
1944
af8bb25a 1945(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1946OS. See L<perlport>.
ed9aa3b7 1947
fe13d51d 1948=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1949
1950(F) The final summary message when a Perl compilation fails.
1951
0ffcbc25
FC
1952=item exists argument is not a HASH or ARRAY element or a subroutine
1953
4a0af295 1954(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1955subroutine with an ampersand, such as:
1956
1957 $foo{$bar}
1958 $ref->{"susie"}[12]
1959 &do_something
1960
1961=item exists argument is not a subroutine name
1962
ccfc2567
FC
1963(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1964and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1965
a0d0e21e
LW
1966=item Exiting eval via %s
1967
be771a83
GS
1968(W exiting) You are exiting an eval by unconventional means, such as a
1969goto, or a loop control statement.
e476b1b5
GS
1970
1971=item Exiting format via %s
1972
9a2ff54b 1973(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1974goto, or a loop control statement.
a0d0e21e 1975
0a753a76
PP
1976=item Exiting pseudo-block via %s
1977
be771a83
GS
1978(W exiting) You are exiting a rather special block construct (like a
1979sort block or subroutine) by unconventional means, such as a goto, or a
1980loop control statement. See L<perlfunc/sort>.
0a753a76 1981
a0d0e21e
LW
1982=item Exiting subroutine via %s
1983
be771a83
GS
1984(W exiting) You are exiting a subroutine by unconventional means, such
1985as a goto, or a loop control statement.
a0d0e21e
LW
1986
1987=item Exiting substitution via %s
1988
be771a83
GS
1989(W exiting) You are exiting a substitution by unconventional means, such
1990as a return, a goto, or a loop control statement.
a0d0e21e 1991
e0e4a6e3 1992=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1993
675fa9ff 1994(F) You wrote something like
c608e803
KW
1995
1996 (?13
1997
1998to denote a capturing group of the form
1999L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2000but omitted the C<")">.
2001
e0e4a6e3 2002=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2003
8b6fbf55
FC
2004(F) The C<(?[...])> extended character class regular expression construct
2005only allows character classes (including character class escapes like
2006C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2007containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2008This allows a regular expression containing just C<(?[...])> to be
2009interpolated. If you see this error message, then you probably
2010have some other C<(?...)> construct inside your character class. See
2011L<perlrecharclass/Extended Bracketed Character Classes>.
2012
baabe3fb 2013=item Experimental aliasing via reference not enabled
1f8155a2 2014
baabe3fb 2015(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2016
baabe3fb
FC
2017 no warnings "experimental::refaliasing";
2018 use feature "refaliasing";
1f8155a2
FC
2019 \$x = \$y;
2020
30d9c59b
Z
2021=item Experimental subroutine signatures not enabled
2022
2023(F) To use subroutine signatures, you must first enable them:
2024
caa35032 2025 no warnings "experimental::signatures";
30d9c59b
Z
2026 use feature "signatures";
2027 sub foo ($left, $right) { ... }
2028
6da34ecb
FC
2029=item Experimental "%s" subs not enabled
2030
2031(F) To use lexical subs, you must first enable them:
2032
2033 no warnings 'experimental::lexical_subs';
2034 use feature 'lexical_subs';
2035 my sub foo { ... }
2036
7b8d334a
GS
2037=item Explicit blessing to '' (assuming package main)
2038
be771a83
GS
2039(W misc) You are blessing a reference to a zero length string. This has
2040the effect of blessing the reference into the package main. This is
2041usually not what you want. Consider providing a default target package,
2042e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2043
6df41af2
GS
2044=item %s: Expression syntax
2045
be771a83
GS
2046(A) You've accidentally run your script through B<csh> instead of Perl.
2047Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2048
2049=item %s failed--call queue aborted
2050
3c10abe3
AG
2051(F) An untrapped exception was raised while executing a UNITCHECK,
2052CHECK, INIT, or END subroutine. Processing of the remainder of the
2053queue of such routines has been prematurely ended.
6df41af2 2054
e0e4a6e3 2055=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2056
98d31c73 2057(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2058character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2059in your false range is interpreted as a literal "-". In a C<(?[...])>
2060construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2061the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2062the problem was discovered. See L<perlre>.
73b437c8 2063
1b1ee2ef 2064=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2065
be771a83
GS
2066(P) An error peculiar to VMS. Something untoward happened in a VMS
2067system service or RTL routine; Perl's exit status should provide more
2068details. The filename in "at %s" and the line number in "line %d" tell
2069you which section of the Perl source code is distressed.
a0d0e21e
LW
2070
2071=item fcntl is not implemented
2072
2073(F) Your machine apparently doesn't implement fcntl(). What is this, a
2074PDP-11 or something?
2075
22846ab4
AB
2076=item FETCHSIZE returned a negative value
2077
2078(F) A tied array claimed to have a negative number of elements, which
2079is not possible.
2080
f337b084
TH
2081=item Field too wide in 'u' format in pack
2082
d8b5cc61 2083(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2084which can't encode values above 63. So there is no point in asking for
2085a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2086C<u63> as the format.
f337b084 2087
af8c498a 2088=item Filehandle %s opened only for input
a0d0e21e 2089
6c8d78fb
HS
2090(W io) You tried to write on a read-only filehandle. If you intended
2091it to be a read-write filehandle, you needed to open it with "+<" or
2092"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2093write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2094
af8c498a 2095=item Filehandle %s opened only for output
a0d0e21e 2096
6c8d78fb
HS
2097(W io) You tried to read from a filehandle opened only for writing, If
2098you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2099with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2100read from the file, use "<". See L<perlfunc/open>. Another possibility
2101is that you attempted to open filedescriptor 0 (also known as STDIN) for
2102output (maybe you closed STDIN earlier?).
97828cef
RGS
2103
2104=item Filehandle %s reopened as %s only for input
2105
2106(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2107as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2108previously.
2109
2110=item Filehandle STDIN reopened as %s only for output
2111
2112(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2113as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2114
2115=item Final $ should be \$ or $name
2116
2117(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2118a literal dollar sign, or was meant to introduce a variable name that
2119happens to be missing. So you have to put either the backslash or the
2120name.
a0d0e21e 2121
56e90b21
GS
2122=item flock() on closed filehandle %s
2123
be771a83 2124(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2125some time before now. Check your control flow. flock() operates on
be771a83
GS
2126filehandles. Are you attempting to call flock() on a dirhandle by the
2127same name?
56e90b21 2128
6df41af2
GS
2129=item Format not terminated
2130
2131(F) A format must be terminated by a line with a solitary dot. Perl got
2132to the end of your file without finding such a line.
2133
a0d0e21e
LW
2134=item Format %s redefined
2135
e476b1b5 2136(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2137
2138 {
271595cc 2139 no warnings 'redefine';
a0d0e21e
LW
2140 eval "format NAME =...";
2141 }
2142
a0d0e21e
LW
2143=item Found = in conditional, should be ==
2144
e476b1b5 2145(W syntax) You said
a0d0e21e
LW
2146
2147 if ($foo = 123)
2148
2149when you meant
2150
2151 if ($foo == 123)
2152
2153(or something like that).
2154
6df41af2
GS
2155=item %s found where operator expected
2156
56da5a46
RGS
2157(S syntax) The Perl lexer knows whether to expect a term or an operator.
2158If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2159operator, it gives you this warning. Usually it indicates that an
2160operator or delimiter was omitted, such as a semicolon.
6df41af2 2161
a0d0e21e
LW
2162=item gdbm store returned %d, errno %d, key "%s"
2163
2164(S) A warning from the GDBM_File extension that a store failed.
2165
2166=item gethostent not implemented
2167
2168(F) Your C library apparently doesn't implement gethostent(), probably
2169because if it did, it'd feel morally obligated to return every hostname
2170on the Internet.
2171
69282e91 2172=item get%sname() on closed socket %s
a0d0e21e 2173
be771a83
GS
2174(W closed) You tried to get a socket or peer socket name on a closed
2175socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2176
748a9306
LW
2177=item getpwnam returned invalid UIC %#o for user "%s"
2178
2179(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2180C<getpwnam> operator returned an invalid UIC.
2181
6df41af2
GS
2182=item getsockopt() on closed socket %s
2183
be771a83
GS
2184(W closed) You tried to get a socket option on a closed socket. Did you
2185forget to check the return value of your socket() call? See
6df41af2
GS
2186L<perlfunc/getsockopt>.
2187
0f539b13
BF
2188=item given is experimental
2189
675fa9ff
FC
2190(S experimental::smartmatch) C<given> depends on smartmatch, which
2191is experimental, so its behavior may change or even be removed
2192in any future release of perl. See the explanation under
2193L<perlsyn/Experimental Details on given and when>.
0f539b13 2194
68567d27
FC
2195=item Global symbol "%s" requires explicit package name (did you forget to
2196declare "my %s"?)
6df41af2 2197
a4edf47d 2198(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2199that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2200declared beforehand using "our", or explicitly qualified to say
2201which package the global variable is in (using "::").
6df41af2 2202
e476b1b5
GS
2203=item glob failed (%s)
2204
5ead438e 2205(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2206for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2207pattern that caused the external program to fail and exit with a
be771a83 2208nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2209resulted in a coredump, this may also mean that your csh (C shell)
2210is broken. If so, you should change all of the csh-related variables
2211in config.sh: If you have tcsh, make the variables refer to it as
2212if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2213all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2214think csh is missing. In either case, after editing config.sh, run
75b44862 2215C<./Configure -S> and rebuild Perl.
e476b1b5 2216
a0d0e21e
LW
2217=item Glob not terminated
2218
2219(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2220a term, so it's looking for the corresponding right angle bracket, and
2221not finding it. Chances are you left some needed parentheses out
2222earlier in the line, and you really meant a "less than".
a0d0e21e 2223
b35b96b6
JH
2224=item gmtime(%f) failed
2225
2226(W overflow) You called C<gmtime> with a number that it could not handle:
2227too large, too small, or NaN. The returned value is C<undef>.
2228
bcd05b94 2229=item gmtime(%f) too large
8b56d6ff 2230
e9200be3 2231(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2232it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2233date. This warning is also triggered with NaN (the special
fc003d4b
MS
2234not-a-number value).
2235
bcd05b94 2236=item gmtime(%f) too small
fc003d4b 2237
e9200be3 2238(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2239it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2240
6df41af2 2241=item Got an error from DosAllocMem
a0d0e21e 2242
6df41af2
GS
2243(P) An error peculiar to OS/2. Most probably you're using an obsolete
2244version of Perl, and this should not happen anyway.
a0d0e21e
LW
2245
2246=item goto must have label
2247
2248(F) Unlike with "next" or "last", you're not allowed to goto an
2249unspecified destination. See L<perlfunc/goto>.
2250
6651ba0b
FC
2251=item Goto undefined subroutine%s
2252
2253(F) You tried to call a subroutine with C<goto &sub> syntax, but
2254the indicated subroutine hasn't been defined, or if it was, it
2255has since been undefined.
2256
6fbc9859 2257=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2258S<<-- HERE> in m/%s/
1f4f6bf1
YO
2259
2260(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2261they must start with a non-digit word character. A common cause of
2262this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2263
5a25739d
FC
2264=item ()-group starts with a count
2265
2266(F) A ()-group started with a count. A count is supposed to follow
2267something: a template character or a ()-group. See L<perlfunc/pack>.
2268
fe13d51d 2269=item %s had compilation errors.
6df41af2
GS
2270
2271(F) The final summary message when a C<perl -c> fails.
2272
a0d0e21e
LW
2273=item Had to create %s unexpectedly
2274
be771a83
GS
2275(S internal) A routine asked for a symbol from a symbol table that ought
2276to have existed already, but for some reason it didn't, and had to be
2277created on an emergency basis to prevent a core dump.
a0d0e21e 2278
6df41af2
GS
2279=item %s has too many errors
2280
2281(F) The parser has given up trying to parse the program after 10 errors.
2282Further error messages would likely be uninformative.
2283
cc4d09e1
KW
2284=item Having more than one /%c regexp modifier is deprecated
2285
2286(D deprecated, regexp) You used the indicated regular expression pattern
2287modifier at least twice in a string of modifiers. It is deprecated to
2288do this with this particular modifier, to allow future extensions to the
2289Perl language.
2290
61e61fbc
JH
2291=item Hexadecimal float: exponent overflow
2292
d8f2b442 2293(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2294than the floating point supports.
2295
2296=item Hexadecimal float: exponent underflow
2297
d8f2b442 2298(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2299than the floating point supports.
2300
cf4f6003
JH
2301=item Hexadecimal float: internal error
2302
2303(F) Something went horribly bad in hexadecimal float handling.
2304
61e61fbc
JH
2305=item Hexadecimal float: mantissa overflow
2306
2307(W overflow) The hexadecimal floating point literal had more bits in
2308the mantissa (the part between the 0x and the exponent, also known as
2309the fraction or the significand) than the floating point supports.
2310
40bca5ae
JH
2311=item Hexadecimal float: precision loss
2312
2313(W overflow) The hexadecimal floating point had internally more
2314digits than could be output. This can be caused by unsupported
2315long double formats, or by 64-bit integers not being available
2316(needed to retrieve the digits under some configurations).
2317
2318=item Hexadecimal float: unsupported long double format
2319
2320(F) You have configured Perl to use long doubles but
d8f2b442 2321the internals of the long double format are unknown;
40bca5ae
JH
2322therefore the hexadecimal float output is impossible.
2323
252aa082
JH
2324=item Hexadecimal number > 0xffffffff non-portable
2325
e476b1b5 2326(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2327(4294967295) and therefore non-portable between systems. See
2328L<perlport> for more on portability concerns.
252aa082 2329
8903cb82
PP
2330=item Identifier too long
2331
2332(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2333about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2334names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2335of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2336
e0e4a6e3
FC
2337=item Ignoring zero length \N{} in character class in regex; marked by
2338S<<-- HERE> in m/%s/
fc8cd66c 2339
f3ba6905 2340(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2341zero-length sequence. When such an escape is used in a character class
2342its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2343been used, and the correct charname handler is in scope.
2344
6df41af2 2345=item Illegal binary digit %s
f675dbe5 2346
6df41af2 2347(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2348
6df41af2 2349=item Illegal binary digit %s ignored
a0d0e21e 2350
be771a83
GS
2351(W digit) You may have tried to use a digit other than 0 or 1 in a
2352binary number. Interpretation of the binary number stopped before the
2353offending digit.
a0d0e21e 2354
6597eb22
FC
2355=item Illegal character after '_' in prototype for %s : %s
2356
e4d150f1
FC
2357(W illegalproto) An illegal character was found in a prototype
2358declaration. The '_' in a prototype must be followed by a ';',
2359indicating the rest of the parameters are optional, or one of '@'
2360or '%', since those two will accept 0 or more final parameters.
6597eb22 2361
78d0fecf 2362=item Illegal character \%o (carriage return)
4fdae800 2363
d5898338 2364(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2365would any other whitespace, which means you should never see this error
2366when Perl was built using standard options. For some reason, your
2367version of Perl appears to have been built without this support. Talk
2368to your Perl administrator.
4fdae800 2369
d37a9538
ST
2370=item Illegal character in prototype for %s : %s
2371
197afce1 2372(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2373Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2374Perhaps you were trying to write a subroutine signature but didn't enable
2375that feature first (C<use feature 'signatures'>), so your signature was
2376instead interpreted as a bad prototype.
d37a9538 2377
904d85c5
RGS
2378=item Illegal declaration of anonymous subroutine
2379
2380(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2381you must always specify a block of code. See L<perlsub>.
904d85c5 2382
8e742a20
MHM
2383=item Illegal declaration of subroutine %s
2384
6903afa2 2385(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2386
a0d0e21e
LW
2387=item Illegal division by zero
2388
be771a83
GS
2389(F) You tried to divide a number by 0. Either something was wrong in
2390your logic, or you need to put a conditional in to guard against
2391meaningless input.
a0d0e21e 2392
6df41af2
GS
2393=item Illegal hexadecimal digit %s ignored
2394
be771a83
GS
2395(W digit) You may have tried to use a character other than 0 - 9 or
2396A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2397number stopped before the illegal character.
6df41af2 2398
a0d0e21e
LW
2399=item Illegal modulus zero
2400
be771a83
GS
2401(F) You tried to divide a number by 0 to get the remainder. Most
2402numbers don't take to this kindly.
a0d0e21e 2403
6df41af2 2404=item Illegal number of bits in vec
399388f4 2405
6df41af2
GS
2406(F) The number of bits in vec() (the third argument) must be a power of
2407two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2408
2409=item Illegal octal digit %s
a0d0e21e 2410
d1be9408 2411(F) You used an 8 or 9 in an octal number.
a0d0e21e 2412
399388f4 2413=item Illegal octal digit %s ignored
748a9306 2414
d1be9408 2415(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2416Interpretation of the octal number stopped before the 8 or 9.
748a9306 2417
e0e4a6e3 2418=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2419
675fa9ff 2420(F) You wrote something like
c608e803
KW
2421
2422 (?+foo)
2423
2424The C<"+"> is valid only when followed by digits, indicating a
2425capturing group. See
2426L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2427
375ed12a
JH
2428=item Illegal suidscript
2429
2430(F) The script run under suidperl was somehow illegal.
2431
fe13d51d 2432=item Illegal switch in PERL5OPT: -%c
6ff81951 2433
6df41af2 2434(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2435following switches: B<-[CDIMUdmtw]>.
6ff81951 2436
6df41af2 2437=item Ill-formed CRTL environ value "%s"
81e118e0 2438
75b44862 2439(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2440internal environ array, and encountered an element without the C<=>
2441delimiter used to separate keys from values. The element is ignored.
09bef843 2442
6df41af2 2443=item Ill-formed message in prime_env_iter: |%s|
54310121 2444
be771a83
GS
2445(W internal) A warning peculiar to VMS. Perl tried to read a logical
2446name or CLI symbol definition when preparing to iterate over %ENV, and
2447didn't see the expected delimiter between key and value, so the line was
2448ignored.
54310121 2449
6df41af2 2450=item (in cleanup) %s
9607fc9c 2451
be771a83
GS
2452(W misc) This prefix usually indicates that a DESTROY() method raised
2453the indicated exception. Since destructors are usually called by the
2454system at arbitrary points during execution, and often a vast number of
2455times, the warning is issued only once for any number of failures that
2456would otherwise result in the same message being repeated.
6df41af2 2457
be771a83
GS
2458Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2459also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2460
e0e4a6e3
FC
2461=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2462in m/%s/
0d0b4b3b 2463
675fa9ff 2464(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2465expression inside the construct was completely empty, or if there are
2466too many or few operands for the number of operators. Perl is not smart
2467enough to give you a more precise indication as to what is wrong.
2468
6fbc9859
MH
2469=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2470parent '%s'
2c7d6b9c
RGS
2471
2472(F) The method resolution order (MRO) of the given class is not
2473C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2474documentation in L<mro> for more information.
2475
979699d9
JH
2476=item In EBCDIC the v-string components cannot exceed 2147483647
2477
2478(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2479Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2480encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2481
6a2ed79a 2482=item Infinite recursion in regex
1a147d38
YO
2483
2484(F) You used a pattern that references itself without consuming any input
6903afa2 2485text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2486either consume text or fail.
2487
6dbe9451
NC
2488=item Initialization of state variables in list context currently forbidden
2489
6903afa2
FC
2490(F) Currently the implementation of "state" only permits the
2491initialization of scalar variables in scalar context. Re-write
2492C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2493context. Constructions such as C<state (@a) = foo()> will be
2494supported in a future perl release.
6dbe9451 2495
2186f873
FC
2496=item %%s[%s] in scalar context better written as $%s[%s]
2497
2498(W syntax) In scalar context, you've used an array index/value slice
2499(indicated by %) to select a single element of an array. Generally
2500it's better to ask for a scalar value (indicated by $). The difference
2501is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2502returns and when evaluating its argument, while C<%foo[&bar]> provides
2503a list context to its subscript, which can do weird things if you're
2504expecting only one subscript. When called in list context, it also
2505returns the index (what C<&bar> returns) in addition to the value.
2506
2507=item %%s{%s} in scalar context better written as $%s{%s}
2508
2509(W syntax) In scalar context, you've used a hash key/value slice
2510(indicated by %) to select a single element of a hash. Generally it's
2511better to ask for a scalar value (indicated by $). The difference
2512is that C<$foo{&bar}> always behaves like a scalar, both in the value
2513it returns and when evaluating its argument, while C<@foo{&bar}> and
2514provides a list context to its subscript, which can do weird things
2515if you're expecting only one subscript. When called in list context,
2516it also returns the key in addition to the value.
2517
a0d0e21e
LW
2518=item Insecure dependency in %s
2519
8b1a09fc 2520(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2521The tainting mechanism is turned on when you're running setuid or
2522setgid, or when you specify B<-T> to turn it on explicitly. The
2523tainting mechanism labels all data that's derived directly or indirectly
2524from the user, who is considered to be unworthy of your trust. If any
2525such data is used in a "dangerous" operation, you get this error. See
2526L<perlsec> for more information.
a0d0e21e
LW
2527
2528=item Insecure directory in %s
2529
be771a83
GS
2530(F) You can't use system(), exec(), or a piped open in a setuid or
2531setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2532the world. Also, the PATH must not contain any relative directory.
2533See L<perlsec>.
a0d0e21e 2534
62f468fc 2535=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2536
2537(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2538setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2539C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2540supplied (or potentially supplied) by the user. The script must set
2541the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2542
0e9be77f
DM
2543=item Insecure user-defined property %s
2544
2545(F) Perl detected tainted data when trying to compile a regular
2546expression that contains a call to a user-defined character property
2547function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2548See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2549
b9ef414d
FC
2550=item Integer overflow in format string for %s
2551
2552(F) The indexes and widths specified in the format string of C<printf()>
2553or C<sprintf()> are too large. The numbers must not overflow the size of
2554integers for your architecture.
2555
a7ae9550
GS
2556=item Integer overflow in %s number
2557
35928bc5 2558(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2559either as a literal or as an argument to hex() or oct() is too big for
2560your architecture, and has been converted to a floating point number.
2561On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2562representable without overflow is 0xFFFFFFFF, 037777777777, or
25630b11111111111111111111111111111111 respectively. Note that Perl
2564transparently promotes all numbers to a floating point representation
2565internally--subject to loss of precision errors in subsequent
2566operations.
bbce6d69 2567
fc89ca81
FC
2568=item Integer overflow in srand
2569
2570(S overflow) The number you have passed to srand is too big to fit
2571in your architecture's integer representation. The number has been
2572replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2573architectures). This means you may be getting less randomness than
2574you expect, because different random seeds above the maximum will
2575return the same sequence of random numbers.
2576
46314c13
JP
2577=item Integer overflow in version
2578
18da5252
FC
2579=item Integer overflow in version %d
2580
784d71ed
FC
2581(W overflow) Some portion of a version initialization is too large for
2582the size of integers for your architecture. This is not a warning
f084e84f 2583because there is no rational reason for a version to try and use an
784d71ed
FC
2584element larger than typically 2**32. This is usually caused by trying
2585to use some odd mathematical operation as a version, like 100/9.
46314c13 2586
e0e4a6e3 2587=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2588
2589(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2590The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2591discovered.
2592
748a9306
LW
2593=item Internal inconsistency in tracking vforks
2594
be771a83
GS
2595(S) A warning peculiar to VMS. Perl keeps track of the number of times
2596you've called C<fork> and C<exec>, to determine whether the current call
2597to C<exec> should affect the current script or a subprocess (see
2598L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2599Perl is making a guess and treating this C<exec> as a request to
2600terminate the Perl script and execute the specified command.
748a9306 2601
870978ae
FC
2602=item internal %<num>p might conflict with future printf extensions
2603
2604(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2605formatting follows a slightly different set of rules when called from
2606C or XS code. Specifically, formats consisting of digits followed
2607by "p" (e.g., "%7p") are reserved for future use. If you see this
2608message, then an XS module tried to call that routine with one such
2609reserved format.
2610
e0e4a6e3 2611=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2612
fa816bf3 2613(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2614S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2615discovered.
a0d0e21e 2616
6df41af2
GS
2617=item %s (...) interpreted as function
2618
75b44862 2619(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2620followed by parentheses turns into a function, with all the list
64977eb6 2621operators arguments found inside the parentheses. See
13a2d996 2622L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2623
f51551f7
FC
2624=item In '(?...)', the '(' and '?' must be adjacent in regex;
2625marked by S<<-- HERE> in m/%s/
2626
2627(F) The two-character sequence C<"(?"> in this context in a regular
2628expression pattern should be an indivisible token, with nothing
2629intervening between the C<"("> and the C<"?">, but you separated them
2630with whitespace.
2631
09bef843
SB
2632=item Invalid %s attribute: %s
2633
a4a4c9e2 2634(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2635by Perl or by a user-supplied handler. See L<attributes>.
2636
2637=item Invalid %s attributes: %s
2638
a4a4c9e2 2639(F) The indicated attributes for a subroutine or variable were not
be771a83 2640recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2641
e0e4a6e3
FC
2642=item Invalid character in charnames alias definition; marked by
2643S<<-- HERE> in '%s
225fb84f
KW
2644
2645(F) You tried to create a custom alias for a character name, with
2646the C<:alias> option to C<use charnames> and the specified character in
2647the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2648
c8028aa6
TC
2649=item Invalid \0 character in %s for %s: %s\0%s
2650
fa3234e3
FC
2651(W syscalls) Embedded \0 characters in pathnames or other system call
2652arguments produce a warning as of 5.20. The parts after the \0 were
2653formerly ignored by system calls.
c8028aa6 2654
e0e4a6e3 2655=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2656
2657(F) Only certain characters are valid for character names. The
2658indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2659
c635e13b
PP
2660=item Invalid conversion in %s: "%s"
2661
be771a83
GS
2662(W printf) Perl does not understand the given format conversion. See
2663L<perlfunc/sprintf>.
c635e13b 2664
e0e4a6e3
FC
2665=item Invalid escape in the specified encoding in regex; marked by
2666S<<-- HERE> in m/%s/
9e08bc66 2667
98d31c73 2668(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2669didn't correspond to a single character through the conversion
2670from the encoding specified by the encoding pragma.
98d31c73
FC
2671The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2672instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2673The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2674escape was discovered.
2675
8149aa9f
FC
2676=item Invalid hexadecimal number in \N{U+...}
2677
e0e4a6e3
FC
2678=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2679S<<-- HERE> in m/%s/
aec0ef10 2680
8149aa9f 2681(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2682number. Either it is empty, or you tried to use a character other than
26830 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2684
6651ba0b
FC
2685=item Invalid module name %s with -%c option: contains single ':'
2686
2687(F) The module argument to perl's B<-m> and B<-M> command-line options
2688cannot contain single colons in the module name, but only in the
2689arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2690B<-MFoo:Bar=baz> is not.
2691
2c7d6b9c
RGS
2692=item Invalid mro name: '%s'
2693
162a3e34
FC
2694(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2695where C<foo> is not a valid method resolution order (MRO). Currently,
2696the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2697a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2698
40e4140b
FC
2699=item Invalid negative number (%s) in chr
2700
2701(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2702not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2703character (U+FFFD).
2704
6651ba0b
FC
2705=item invalid option -D%c, use -D'' to see choices
2706
8ff21bfe
FC
2707(S debugging) Perl was called with invalid debugger flags. Call perl
2708with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2709See also L<perlrun/-Dletters>.
6651ba0b 2710
e0e4a6e3 2711=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2712
2713(F) The range specified in a character class had a minimum character
7253e4e3
RK
2714greater than the maximum character. One possibility is that you forgot the
2715C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2716up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2717problem was discovered. See L<perlre>.
6df41af2 2718
d1573ac7 2719=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2720
2721(F) The range specified in the tr/// or y/// operator had a minimum
2722character greater than the maximum character. See L<perlop>.
2723
09bef843
SB
2724=item Invalid separator character %s in attribute list
2725
0120eecf 2726(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2727elements of an attribute list. If the previous attribute had a
2728parenthesised parameter list, perhaps that list was terminated too soon.
2729See L<attributes>.
09bef843 2730
b4581f09
JH
2731=item Invalid separator character %s in PerlIO layer specification %s
2732
2bfc5f71
FC
2733(W layer) When pushing layers onto the Perl I/O system, something other
2734than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2735If the previous attribute had a parenthesised parameter list, perhaps that
2736list was terminated too soon.
2737
2c86d456
DG
2738=item Invalid strict version format (%s)
2739
fa816bf3 2740(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2741A "strict" version number is a positive decimal number (integer or
2742decimal-fraction) without exponentiation or else a dotted-decimal
2743v-string with a leading 'v' character and at least three components.
a6485a24 2744The parenthesized text indicates which criteria were not met.
2c86d456
DG
2745See the L<version> module for more details on allowed version formats.
2746
49704364 2747=item Invalid type '%s' in %s
96e4d5b1 2748
49704364
LW
2749(F) The given character is not a valid pack or unpack type.
2750See L<perlfunc/pack>.
6728c851 2751
49704364 2752(W) The given character is not a valid pack or unpack type but used to be
75b44862 2753silently ignored.
96e4d5b1 2754
2c86d456
DG
2755=item Invalid version format (%s)
2756
fa816bf3 2757(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2758A "lax" version number is a positive decimal number (integer or
2759decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2760v-string. If the v-string has fewer than three components, it
2761must have a leading 'v' character. Otherwise, the leading 'v' is
2762optional. Both decimal and dotted-decimal versions may have a
2763trailing "alpha" component separated by an underscore character
2764after a fractional or dotted-decimal component. The parenthesized
2765text indicates which criteria were not met. See the L<version> module
2766for more details on allowed version formats.
46314c13 2767
798ae1b7
DG
2768=item Invalid version object
2769
fa816bf3
FC
2770(F) The internal structure of the version object was invalid.
2771Perhaps the internals were modified directly in some way or
2772an arbitrary reference was blessed into the "version" class.
798ae1b7 2773
cd209d9d 2774=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2775marked by S<<-- HERE> in m/%s/
675fa9ff 2776
cd209d9d 2777(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2778this context in a regular expression pattern should be an
2779indivisible token, with nothing intervening between the C<"(">
cd209d9d 2780and the C<"*">, but you separated them.
675fa9ff 2781
a0d0e21e
LW
2782=item ioctl is not implemented
2783
2784(F) Your machine apparently doesn't implement ioctl(), which is pretty
2785strange for a machine that supports C.
2786
c289d2f7
JH
2787=item ioctl() on unopened %s
2788
2789(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2790Check your control flow and number of arguments.
c289d2f7 2791
fe13d51d 2792=item IO layers (like '%s') unavailable
363c40c4
SB
2793
2794(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2795you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2796with 'useperlio'.
2797
80cbd5ad
JH
2798=item IO::Socket::atmark not implemented on this architecture
2799
2800(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2801neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2802
4f650b80 2803=item $* is no longer supported
b4581f09 2804
4f650b80 2805(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2806perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2807previous versions of perl the use of C<$*> enabled or disabled multi-line
2808matching within a string.
4fd19576
B
2809
2810Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2811modifiers. You can enable C</m> for a lexical scope (even a whole file)
2812with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2813then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2814
8ae1fe26
RGS
2815=item $# is no longer supported
2816
a58ac25e 2817(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2818perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2819should use the printf/sprintf functions instead.
8ae1fe26 2820
ccf3535a 2821=item '%s' is not a code reference
6ad11d81 2822
6903afa2
FC
2823(W overload) The second (fourth, sixth, ...) argument of
2824overload::constant needs to be a code reference. Either
2825an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2826
ccf3535a 2827=item '%s' is not an overloadable type
6ad11d81 2828
04a80ee0
RGS
2829(W overload) You tried to overload a constant type the overload package is
2830unaware of.
6ad11d81 2831
5a25739d
FC
2832=item -i used with no filenames on the command line, reading from STDIN
2833
2834(S inplace) The C<-i> option was passed on the command line, indicating
2835that the script is intended to edit files in place, but no files were
2836given. This is usually a mistake, since editing STDIN in place doesn't
2837make sense, and can be confusing because it can make perl look like
2838it is hanging when it is really just trying to read from STDIN. You
2839should either pass a filename to edit, or remove C<-i> from the command
2840line. See L<perlrun> for more details.
2841
aec0ef10 2842=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2843
2844(P) The regular expression parser is confused.
2845
0953b66b
FC
2846=item keys on reference is experimental
2847
0773cb3e
FC
2848(S experimental::autoderef) C<keys> with a scalar argument is experimental
2849and may change or be removed in a future Perl version. If you want to
2850take the risk of using this feature, simply disable this warning:
0953b66b 2851
d401967c 2852 no warnings "experimental::autoderef";
0953b66b 2853
a0d0e21e
LW
2854=item Label not found for "last %s"
2855
be771a83
GS
2856(F) You named a loop to break out of, but you're not currently in a loop
2857of that name, not even if you count where you were called from. See
2858L<perlfunc/last>.
a0d0e21e
LW
2859
2860=item Label not found for "next %s"
2861
2862(F) You named a loop to continue, but you're not currently in a loop of
2863that name, not even if you count where you were called from. See
2864L<perlfunc/last>.
2865
2866=item Label not found for "redo %s"
2867
2868(F) You named a loop to restart, but you're not currently in a loop of
2869that name, not even if you count where you were called from. See
2870L<perlfunc/last>.
2871
85ab1d1d 2872=item leaving effective %s failed
5ff3f7a4 2873
85ab1d1d 2874(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2875effective uids or gids failed.
2876
49704364
LW
2877=item length/code after end of string in unpack
2878
d7f8936a 2879(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2880length/code combination tried to obtain more data. This results in
2881an undefined value for the length. See L<perlfunc/pack>.
49704364 2882
25e26107 2883=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2884
0d46a4e7
FC
2885(W syntax) You used length() on either an array or a hash when you
2886probably wanted a count of the items.
e508c8a4
MH
2887
2888Array size can be obtained by doing:
2889
2890 scalar(@array);
2891
2892The number of items in a hash can be obtained by doing:
2893
2894 scalar(keys %hash);
2895
f0e67a1d
Z
2896=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2897
d4fe7078
RS
2898(F) An extension is attempting to insert text into the current parse
2899(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2900couldn't be part of the current input. This is an inherent pitfall
2901of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2902it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2903
2904=item Lexing code internal error (%s)
2905
2906(F) Lexing code supplied by an extension violated the lexer's API in a
2907detectable way.
2908
69282e91 2909=item listen() on closed socket %s
a0d0e21e 2910
be771a83
GS
2911(W closed) You tried to do a listen on a closed socket. Did you forget
2912to check the return value of your socket() call? See
2913L<perlfunc/listen>.
a0d0e21e 2914
6651ba0b
FC
2915=item List form of piped open not implemented
2916
2917(F) On some platforms, notably Windows, the three-or-more-arguments
2918form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2919Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2920
b35b96b6
JH
2921=item localtime(%f) failed
2922
2923(W overflow) You called C<localtime> with a number that it could not handle:
2924too large, too small, or NaN. The returned value is C<undef>.
2925
bcd05b94 2926=item localtime(%f) too large
8b56d6ff 2927
e9200be3 2928(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2929than it can reliably handle and C<localtime> probably returned the
6903afa2 2930wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2931not-a-number value).
2932
bcd05b94 2933=item localtime(%f) too small
fc003d4b 2934
e9200be3 2935(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2936than it can reliably handle and C<localtime> probably returned the
e7a1a147 2937wrong date.
8b56d6ff 2938
58e23c8d 2939=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2940
2941(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2942handle. This restriction may be eased in a future release.
2e50fd82 2943
b88df990
NC
2944=item Lost precision when %s %f by 1
2945
e63e8a91
FC
2946(W imprecision) The value you attempted to increment or decrement by one
2947is too large for the underlying floating point representation to store
2948accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2949warning because it has already switched from integers to floating point
2950when values are too large for integers, and now even floating point is
2951insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2952
93fad930 2953=item lstat() on filehandle%s
2f7da168
RK
2954
2955(W io) You tried to do an lstat on a filehandle. What did you mean
2956by that? lstat() makes sense only on filenames. (Perl did a fstat()
2957instead on the filehandle.)
2958
345d70e3 2959=item lvalue attribute %s already-defined subroutine
bb3abb05 2960
345d70e3
FC
2961(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2962attribute on or off on a Perl subroutine that is already defined
2963does not always work properly. It may or may not do what you
2964want, depending on what code is inside the subroutine, with exact
2965details subject to change between Perl versions. Only do this
2966if you really know what you are doing.
bb3abb05 2967
885ef6f5
GG
2968=item lvalue attribute ignored after the subroutine has been defined
2969
345d70e3
FC
2970(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2971subroutine an lvalue subroutine after it has been defined is
2972not permitted. To make the subroutine an lvalue subroutine,
2973add the lvalue attribute to the definition, or put the C<sub
2974foo :lvalue;> declaration before the definition.
2975
2976See also L<attributes.pm|attributes>.
885ef6f5 2977
6f1b3ab0
FC
2978=item Magical list constants are not supported
2979
2980(F) You assigned a magical array to a stash element, and then tried
2981to use the subroutine from the same slot. You are asking Perl to do
2982something it cannot do, details subject to change between Perl versions.
2983
2db62bbc 2984=item Malformed integer in [] in pack
49704364 2985
2db62bbc 2986(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2987are permitted. See L<perlfunc/pack>.
2988
2989=item Malformed integer in [] in unpack
2990
2db62bbc 2991(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2992are permitted. See L<perlfunc/pack>.
2993
6df41af2
GS
2994=item Malformed PERLLIB_PREFIX
2995
2996(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2997
2998 prefix1;prefix2
2999
3000or
6df41af2
GS
3001 prefix1 prefix2
3002
be771a83
GS
3003with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3004a builtin library search path, prefix2 is substituted. The error may
3005appear if components are not found, or are too long. See
fecfaeb8 3006"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3007
2f758a16
ST
3008=item Malformed prototype for %s: %s
3009
d37a9538
ST
3010(F) You tried to use a function with a malformed prototype. The
3011syntax of function prototypes is given a brief compile-time check for
3012obvious errors like invalid characters. A more rigorous check is run
3013when the function is called.
30d9c59b
Z
3014Perhaps the function's author was trying to write a subroutine signature
3015but didn't enable that feature first (C<use feature 'signatures'>),
3016so the signature was instead interpreted as a bad prototype.
2f758a16 3017
ba210ebe
JH
3018=item Malformed UTF-8 character (%s)
3019
4d6f11e5 3020(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3021encoding rules, even though it had the UTF8 flag on.
ba210ebe 3022
2575c402
JW
3023One possible cause is that you set the UTF8 flag yourself for data that
3024you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 30258-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3026
3027If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3028sequences are handled gracefully, but if you use C<:utf8>, the flag is
3029set without validating the data, possibly resulting in this error
3030message.
3031
3032See also L<Encode/"Handling Malformed Data">.
901b21bf 3033
107160e2
KW
3034=item Malformed UTF-8 character immediately after '%s'
3035
3036(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3037encoding rules. The message prints out the properly encoded characters
3038just before the first bad one. If C<utf8> warnings are enabled, a
3039warning is generated that gives more details about the type of
3040malformation.
3041
bde9e88d 3042=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3043
3044(F) The charnames handler returned malformed UTF-8.
3045
4a5d3a93
FC
3046=item Malformed UTF-8 string in '%c' format in unpack
3047
3048(F) You tried to unpack something that didn't comply with UTF-8 encoding
3049rules and perl was unable to guess how to make more progress.
3050
f337b084
TH
3051=item Malformed UTF-8 string in pack
3052
3053(F) You tried to pack something that didn't comply with UTF-8 encoding
3054rules and perl was unable to guess how to make more progress.
3055
3056=item Malformed UTF-8 string in unpack
3057
3058(F) You tried to unpack something that didn't comply with UTF-8 encoding
3059rules and perl was unable to guess how to make more progress.
3060
4a5d3a93 3061=item Malformed UTF-16 surrogate
f337b084 3062
4a5d3a93
FC
3063(F) Perl thought it was reading UTF-16 encoded character data but while
3064doing it Perl met a malformed Unicode surrogate.
3065
30d9c59b
Z
3066=item Mandatory parameter follows optional parameter
3067
3068(F) In a subroutine signature, you wrote something like "$a = undef,
3069$b", making an earlier parameter optional and a later one mandatory.
3070Parameters are filled from left to right, so it's impossible for the
3071caller to omit an earlier one and pass a later one. If you want to act
3072as if the parameters are filled from right to left, declare the rightmost
3073optional and then shuffle the parameters around in the subroutine's body.
3074
2d88a86a
KW
3075=item Matched non-Unicode code point 0x%X against Unicode property; may
3076not be portable
3077
3078(S non_unicode) Perl allows strings to contain a superset of
3079Unicode code points; each code point may be as large as what is storable
3080in an unsigned integer on your system, but these may not be accepted by
3081other languages/systems. This message occurs when you matched a string
3082containing such a code point against a regular expression pattern, and
3083the code point was matched against a Unicode property, C<\p{...}> or
3084C<\P{...}>. Unicode properties are only defined on Unicode code points,
3085so the result of this match is undefined by Unicode, but Perl (starting
3086in v5.20) treats non-Unicode code points as if they were typical
3087unassigned Unicode ones, and matched this one accordingly. Whether a
3088given property matches these code points or not is specified in
3089L<perluniprops/Properties accessible through \p{} and \P{}>.
3090
3091This message is suppressed (unless it has been made fatal) if it is
3092immaterial to the results of the match if the code point is Unicode or
3093not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3094the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3095Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3096every code point except these 22.)
3097
3098Getting this message indicates that the outcome of the match arguably
3099should have been the opposite of what actually happened. If you think
3100that is the case, you may wish to make the C<non_unicode> warnings
3101category fatal; if you agree with Perl's decision, you may wish to turn
3102off this category.
3103
3104See L<perlunicode/Beyond Unicode code points> for more information.
3105
e0e4a6e3
FC
3106=item %s matches null string many times in regex; marked by S<<-- HERE> in
3107m/%s/
4a5d3a93
FC
3108
3109(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3110regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3111shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3112See L<perlre>.
f337b084 3113
de42a5a9 3114=item Maximal count of pending signals (%u) exceeded
2563cec5 3115
6903afa2 3116(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3117usually indicates that your operating system tried to deliver signals
3118too fast (with a very high priority), starving the perl process from
3119resources it would need to reach a point where it can process signals
6903afa2 3120safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3121
25f58aea
PN
3122=item "%s" may clash with future reserved word
3123
3124(W) This warning may be due to running a perl5 script through a perl4
3125interpreter, especially if the word that is being warned about is
3126"use" or "my".
3127
0d2487cd 3128=item '%' may not be used in pack
6df41af2
GS
3129
3130(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3131checksumming process loses information, and you can't go the other way.
3132See L<perlfunc/unpack>.
6df41af2 3133
a0d0e21e
LW
3134=item Method for operation %s not found in package %s during blessing
3135
3136(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3137doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3138
3cdd684c
TP
3139=item Method %s not permitted
3140
3141See Server error.
3142
a0d0e21e
LW
3143=item Might be a runaway multi-line %s string starting on line %d
3144
3145(S) An advisory indicating that the previous error may have been caused
3146by a missing delimiter on a string or pattern, because it eventually
3147ended earlier on the current line.
3148
3149=item Misplaced _ in number
3150
d4ced10d
JH
3151(W syntax) An underscore (underbar) in a numeric constant did not
3152separate two digits.
a0d0e21e 3153
7baa4690
HS
3154=item Missing argument in %s
3155
3664866e
AB
3156(W missing) You called a function with fewer arguments than other
3157arguments you supplied indicated would be needed.
3158
3159Currently only emitted when a printf-type format required more
3160arguments than were supplied, but might be used in the future for
3161other cases where we can statically determine that arguments to
3162functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3163
9e81e6a1
RGS
3164=item Missing argument to -%c
3165
3166(F) The argument to the indicated command line switch must follow
3167immediately after the switch, without intervening spaces.
3168
ff3f963a 3169=item Missing braces on \N{}
423cee85 3170
e0e4a6e3 3171=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3172
4a2d328f 3173(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3174double-quotish context. This can also happen when there is a space
3175(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3176This modifier does not change the requirement that the brace immediately
3177follow the C<\N>.
423cee85 3178
f0a2b745
KW
3179=item Missing braces on \o{}
3180
3181(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3182
a0d0e21e
LW
3183=item Missing comma after first argument to %s function
3184
3185(F) While certain functions allow you to specify a filehandle or an
3186"indirect object" before the argument list, this ain't one of them.
3187
06eaf0bc
GS
3188=item Missing command in piped open
3189
be771a83
GS
3190(W pipe) You used the C<open(FH, "| command")> or
3191C<open(FH, "command |")> construction, but the command was missing or
3192blank.
06eaf0bc 3193
961ce445
RGS
3194=item Missing control char name in \c
3195
3196(F) A double-quoted string ended with "\c", without the required control
3197character name.
3198
591f5ca2
FC
3199=item Missing ']' in prototype for %s : %s
3200
bfe11873 3201(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3202
8767b1ab 3203=item Missing name in "%s sub"
6df41af2 3204
87444db5 3205(F) The syntax for lexically scoped subroutines requires that
be771a83 3206they have a name with which they can be found.
6df41af2
GS
3207
3208=item Missing $ on loop variable
3209
be771a83
GS
3210(F) Apparently you've been programming in B<csh> too much. Variables
3211are always mentioned with the $ in Perl, unlike in the shells, where it
3212can vary from one line to the next.
6df41af2 3213
cc507455 3214=item (Missing operator before %s?)
748a9306 3215
56da5a46
RGS
3216(S syntax) This is an educated guess made in conjunction with the message
3217"%s found where operator expected". Often the missing operator is a comma.
748a9306 3218
f51551f7
FC
3219=item Missing or undefined argument to require
3220
3221(F) You tried to call require with no argument or with an undefined
3222value as an argument. Require expects either a package name or a
3223file-specification as an argument. See L<perlfunc/require>.
3224
e0e4a6e3 3225=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3226
ff3f963a
KW
3227(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3228
4a68bf9d 3229=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3230
d32207c9
FC
3231(F) C<\N> has two meanings.
3232
3233The traditional one has it followed by a name enclosed in braces,
3234meaning the character (or sequence of characters) given by that
fa816bf3 3235name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3236double-quoted strings and regular expression patterns. In patterns,
3237it doesn't have the meaning an unescaped C<*> does.
3238
3239Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3240in patterns, namely to match a non-newline character. (This is short
3241for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3242
3243This can lead to some ambiguities. When C<\N> is not followed immediately
3244by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3245form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3246means to match the given quantity of non-newlines (in these examples,
32473; and 5 or more, respectively). In all other case, where there is a
3248C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3249
3250However, if there is no matching C<}>, Perl doesn't know if it was
3251mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3252If you meant the former, add the right brace; if you meant the latter,
3253escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3254
d98d5fff 3255=item Missing right curly or square bracket
a0d0e21e 3256
be771a83
GS
3257(F) The lexer counted more opening curly or square brackets than closing
3258ones. As a general rule, you'll find it's missing near the place you
3259were last editing.
a0d0e21e 3260
6df41af2
GS
3261=item (Missing semicolon on previous line?)
3262
56da5a46
RGS
3263(S syntax) This is an educated guess made in conjunction with the message
3264"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3265the previous line just because you saw this message.
3266
a0d0e21e
LW
3267=item Modification of a read-only value attempted
3268
3269(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3270constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3271catches that. But an easy way to do the same thing is:
3272
3273 sub mod { $_[0] = 1 }
3274 mod(2);
3275
3276Another way is to assign to a substr() that's off the end of the string.
3277
c5674021
PDF
3278Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3279is aliased to a constant in the look I<LIST>:
3280
b7e4ecc1
FC
3281 $x = 1;
3282 foreach my $n ($x, 2) {
3283 $n *= 2; # modifies the $x, but fails on attempt to
3284 } # modify the 2
c5674021 3285
7a4340ed 3286=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3287
3288(F) You tried to make an array value spring into existence, and the
3289subscript was probably negative, even counting from end of the array
3290backwards.
3291
7a4340ed 3292=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3293
be771a83
GS
3294(P) You tried to make a hash value spring into existence, and it
3295couldn't be created for some peculiar reason.
a0d0e21e
LW
3296
3297=item Module name must be constant
3298
3299(F) Only a bare module name is allowed as the first argument to a "use".
3300
be98fb35 3301=item Module name required with -%c option
6df41af2 3302
be98fb35
GS
3303(F) The C<-M> or C<-m> options say that Perl should load some module, but
3304you omitted the name of the module. Consult L<perlrun> for full details
3305about C<-M> and C<-m>.
6df41af2 3306
fe13d51d 3307=item More than one argument to '%s' open
ed9aa3b7 3308
6903afa2 3309(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3310can happen if you are trying to open a pipe to a command that takes a
3311list of arguments, but have forgotten to specify a piped open mode.
3312See L<perlfunc/open> for details.
3313
85396b18
FC
3314=item mprotect for COW string %p %u failed with %d
3315
3316(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3317L<perlguts/"Copy on Write">), but a shared string buffer
3318could not be made read-only.
3319
92951bce
FC
3320=item mprotect for %p %u failed with %d
3321
85396b18
FC
3322(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),