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perldelta for refaliasing
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1=head1 NAME
2
3perldiag - various Perl diagnostics
4
5=head1 DESCRIPTION
6
7These messages are classified as follows (listed in increasing order of
8desperation):
9
10 (W) A warning (optional).
d1d15184 11 (D) A deprecation (enabled by default).
00eb3f2b 12 (S) A severe warning (enabled by default).
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13 (F) A fatal error (trappable).
14 (P) An internal error you should never see (trappable).
54310121 15 (X) A very fatal error (nontrappable).
cb1a09d0 16 (A) An alien error message (not generated by Perl).
a0d0e21e 17
75b44862 18The majority of messages from the first three classifications above
64977eb6 19(W, D & S) can be controlled using the C<warnings> pragma.
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20
21If a message can be controlled by the C<warnings> pragma, its warning
22category is included with the classification letter in the description
466416ed 23below. E.g. C<(W closed)> means a warning in the C<closed> category.
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24
25Optional warnings are enabled by using the C<warnings> pragma or the B<-w>
fa816bf3 26and B<-W> switches. Warnings may be captured by setting C<$SIG{__WARN__}>
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27to a reference to a routine that will be called on each warning instead
28of printing it. See L<perlvar>.
29
b7eceb5b 30Severe warnings are always enabled, unless they are explicitly disabled
e476b1b5 31with the C<warnings> pragma or the B<-X> switch.
4438c4b7 32
748a9306 33Trappable errors may be trapped using the eval operator. See
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34L<perlfunc/eval>. In almost all cases, warnings may be selectively
35disabled or promoted to fatal errors using the C<warnings> pragma.
36See L<warnings>.
a0d0e21e 37
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38The messages are in alphabetical order, without regard to upper or
39lower-case. Some of these messages are generic. Spots that vary are
40denoted with a %s or other printf-style escape. These escapes are
41ignored by the alphabetical order, as are all characters other than
42letters. To look up your message, just ignore anything that is not a
43letter.
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44
45=over 4
46
6df41af2 47=item accept() on closed socket %s
33633739 48
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49(W closed) You tried to do an accept on a closed socket. Did you forget
50to check the return value of your socket() call? See
51L<perlfunc/accept>.
33633739 52
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53=item Aliasing via reference is experimental
54
55(S experimental::refaliasing) This warning is emitted if you use
56a reference constructor on the left-hand side of an assignment to
57alias one variable to another. Simply suppress the warning if you
58want to use the feature, but know that in doing so you are taking
59the risk of using an experimental feature which may change or be
60removed in a future Perl version:
61
62 no warnings "experimental::refaliasing";
63 use feature "refaliasing";
64 \$x = \$y;
65
de42a5a9 66=item Allocation too large: %x
a0d0e21e 67
6df41af2 68(X) You can't allocate more than 64K on an MS-DOS machine.
a0d0e21e 69
04f74579 70=item '%c' allowed only after types %s in %s
ef54e1a4 71
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72(F) The modifiers '!', '<' and '>' are allowed in pack() or unpack() only
73after certain types. See L<perlfunc/pack>.
ef54e1a4 74
6df41af2 75=item Ambiguous call resolved as CORE::%s(), qualify as such or use &
43192e07 76
75b44862 77(W ambiguous) A subroutine you have declared has the same name as a Perl
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78keyword, and you have used the name without qualification for calling
79one or the other. Perl decided to call the builtin because the
80subroutine is not imported.
43192e07 81
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82To force interpretation as a subroutine call, either put an ampersand
83before the subroutine name, or qualify the name with its package.
84Alternatively, you can import the subroutine (or pretend that it's
85imported with the C<use subs> pragma).
43192e07 86
6df41af2 87To silently interpret it as the Perl operator, use the C<CORE::> prefix
496a33f5 88on the operator (e.g. C<CORE::log($x)>) or declare the subroutine
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89to be an object method (see L<perlsub/"Subroutine Attributes"> or
90L<attributes>).
43192e07 91
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92=item Ambiguous range in transliteration operator
93
94(F) You wrote something like C<tr/a-z-0//> which doesn't mean anything at
95all. To include a C<-> character in a transliteration, put it either
96first or last. (In the past, C<tr/a-z-0//> was synonymous with
97C<tr/a-y//>, which was probably not what you would have expected.)
98
6df41af2 99=item Ambiguous use of %s resolved as %s
43192e07 100
7c7af292 101(S ambiguous) You said something that may not be interpreted the way
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102you thought. Normally it's pretty easy to disambiguate it by supplying
103a missing quote, operator, parenthesis pair or declaration.
a0d0e21e 104
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105=item Ambiguous use of -%s resolved as -&%s()
106
107(S ambiguous) You wrote something like C<-foo>, which might be the
108string C<"-foo">, or a call to the function C<foo>, negated. If you meant
109the string, just write C<"-foo">. If you meant the function call,
110write C<-foo()>.
111
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112=item Ambiguous use of %c resolved as operator %c
113
7c7af292 114(S ambiguous) C<%>, C<&>, and C<*> are both infix operators (modulus,
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115bitwise and, and multiplication) I<and> initial special characters
116(denoting hashes, subroutines and typeglobs), and you said something
117like C<*foo * foo> that might be interpreted as either of them. We
118assumed you meant the infix operator, but please try to make it more
119clear -- in the example given, you might write C<*foo * foo()> if you
120really meant to multiply a glob by the result of calling a function.
d8225693 121
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122=item Ambiguous use of %c{%s} resolved to %c%s
123
124(W ambiguous) You wrote something like C<@{foo}>, which might be
125asking for the variable C<@foo>, or it might be calling a function
126named foo, and dereferencing it as an array reference. If you wanted
1cecf2c0 127the variable, you can just write C<@foo>. If you wanted to call the
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128function, write C<@{foo()}> ... or you could just not have a variable
129and a function with the same name, and save yourself a lot of trouble.
130
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131=item Ambiguous use of %c{%s[...]} resolved to %c%s[...]
132
133=item Ambiguous use of %c{%s{...}} resolved to %c%s{...}
4da60377 134
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135(W ambiguous) You wrote something like C<${foo[2]}> (where foo represents
136the name of a Perl keyword), which might be looking for element number
1372 of the array named C<@foo>, in which case please write C<$foo[2]>, or you
138might have meant to pass an anonymous arrayref to the function named
139foo, and then do a scalar deref on the value it returns. If you meant
140that, write C<${foo([2])}>.
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141
142In regular expressions, the C<${foo[2]}> syntax is sometimes necessary
143to disambiguate between array subscripts and character classes.
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144C</$length[2345]/>, for instance, will be interpreted as C<$length> followed
145by the character class C<[2345]>. If an array subscript is what you
146want, you can avoid the warning by changing C</${length[2345]}/> to the
147unsightly C</${\$length[2345]}/>, by renaming your array to something
148that does not coincide with a built-in keyword, or by simply turning
149off warnings with C<no warnings 'ambiguous';>.
4da60377 150
6df41af2 151=item '|' and '<' may not both be specified on command line
a0d0e21e 152
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153(F) An error peculiar to VMS. Perl does its own command line
154redirection, and found that STDIN was a pipe, and that you also tried to
155redirect STDIN using '<'. Only one STDIN stream to a customer, please.
c9f97d15 156
6df41af2 157=item '|' and '>' may not both be specified on command line
1028017a 158
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159(F) An error peculiar to VMS. Perl does its own command line
160redirection, and thinks you tried to redirect stdout both to a file and
161into a pipe to another command. You need to choose one or the other,
162though nothing's stopping you from piping into a program or Perl script
163which 'splits' output into two streams, such as
1028017a 164
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165 open(OUT,">$ARGV[0]") or die "Can't write to $ARGV[0]: $!";
166 while (<STDIN>) {
167 print;
168 print OUT;
169 }
170 close OUT;
c9f97d15 171
6df41af2 172=item Applying %s to %s will act on scalar(%s)
eb6e2d6f 173
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174(W misc) The pattern match (C<//>), substitution (C<s///>), and
175transliteration (C<tr///>) operators work on scalar values. If you apply
be771a83 176one of them to an array or a hash, it will convert the array or hash to
ac036724 177a scalar value (the length of an array, or the population info of a
178hash) and then work on that scalar value. This is probably not what
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179you meant to do. See L<perlfunc/grep> and L<perlfunc/map> for
180alternatives.
eb6e2d6f 181
6df41af2 182=item Arg too short for msgsnd
76cd736e 183
6df41af2 184(F) msgsnd() requires a string at least as long as sizeof(long).
76cd736e 185
f86702cc 186=item Argument "%s" isn't numeric%s
a0d0e21e 187
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188(W numeric) The indicated string was fed as an argument to an operator
189that expected a numeric value instead. If you're fortunate the message
190will identify which operator was so unfortunate.
a0d0e21e 191
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192=item Argument list not closed for PerlIO layer "%s"
193
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194(W layer) When pushing a layer with arguments onto the Perl I/O
195system you forgot the ) that closes the argument list. (Layers
196take care of transforming data between external and internal
197representations.) Perl stopped parsing the layer list at this
198point and did not attempt to push this layer. If your program
199didn't explicitly request the failing operation, it may be the
200result of the value of the environment variable PERLIO.
b4581f09 201
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202=item Argument "%s" treated as 0 in increment (++)
203
204(W numeric) The indicated string was fed as an argument to the C<++>
205operator which expects either a number or a string matching
206C</^[a-zA-Z]*[0-9]*\z/>. See L<perlop/Auto-increment and
207Auto-decrement> for details.
208
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209=item assertion botched: %s
210
21b5e840 211(X) The malloc package that comes with Perl had an internal failure.
a0d0e21e 212
0eacef8e 213=item Assertion %s failed: file "%s", line %d
a0d0e21e 214
21b5e840 215(X) A general assertion failed. The file in question must be examined.
a0d0e21e 216
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217=item Assigned value is not a reference
218
219(F) You tried to assign something that was not a reference to an lvalue
220reference (e.g., C<\$x = $y>). If you meant to make $x an alias to $y, use
221C<\$x = \$y>.
222
223=item Assigned value is not %s reference
224
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225(F) You tried to assign a reference to a reference constructor, but the
226two references were not of the same type. You cannot alias a scalar to
227an array, or an array to a hash; the two types must match.
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228
229 \$x = \@y; # error
230 \@x = \%y; # error
231 $y = [];
232 \$x = $y; # error; did you mean \$y?
233
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234=item Assigning non-zero to $[ is no longer possible
235
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236(F) When the "array_base" feature is disabled (e.g., under C<use v5.16;>)
237the special variable C<$[>, which is deprecated, is now a fixed zero value.
82122228 238
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239=item Assignment to both a list and a scalar
240
241(F) If you assign to a conditional operator, the 2nd and 3rd arguments
242must either both be scalars or both be lists. Otherwise Perl won't
243know which context to supply to the right side.
244
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245=item <> at require-statement should be quotes
246
247(F) You wrote C<< require <file> >> when you should have written
248C<require 'file'>.
249
2393f1b9 250=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 251
49293501 252(F) The failing code has attempted to get or set a key which is not in
2393f1b9 253the current set of allowed keys of a restricted hash.
49293501 254
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255=item Attempt to bless into a freed package
256
257(F) You wrote C<bless $foo> with one argument after somehow causing
258the current package to be freed. Perl cannot figure out what to
259do, so it throws up in hands in despair.
260
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261=item Attempt to bless into a reference
262
263(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 264the name of the package to bless the resulting object into. You've
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265supplied instead a reference to something: perhaps you wrote
266
267 bless $self, $proto;
268
269when you intended
270
271 bless $self, ref($proto) || $proto;
272
273If you actually want to bless into the stringified version
274of the reference supplied, you need to stringify it yourself, for
275example by:
276
277 bless $self, "$proto";
278
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279=item Attempt to clear deleted array
280
281(S debugging) An array was assigned to when it was being freed.
282Freed values are not supposed to be visible to Perl code. This
283can also happen if XS code calls C<av_clear> from a custom magic
284callback on the array.
285
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286=item Attempt to delete disallowed key '%s' from a restricted hash
287
288(F) The failing code attempted to delete from a restricted hash a key
289which is not in its key set.
290
291=item Attempt to delete readonly key '%s' from a restricted hash
292
293(F) The failing code attempted to delete a key whose value has been
294declared readonly from a restricted hash.
295
de42a5a9 296=item Attempt to free non-arena SV: 0x%x
a0d0e21e 297
f84fe999 298(S internal) All SV objects are supposed to be allocated from arenas
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299that will be garbage collected on exit. An SV was discovered to be
300outside any of those arenas.
a0d0e21e 301
12578ffb 302=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 303
f84fe999 304(S internal) Perl maintains a reference-counted internal table of
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305strings to optimize the storage and access of hash keys and other
306strings. This indicates someone tried to decrement the reference count
307of a string that can no longer be found in the table.
bbce6d69 308
7d5b40b4 309=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 310
f84fe999 311(S debugging) Mortalized values are supposed to be freed by the
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312free_tmps() routine. This indicates that something else is freeing the
313SV before the free_tmps() routine gets a chance, which means that the
314free_tmps() routine will be freeing an unreferenced scalar when it does
315try to free it.
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316
317=item Attempt to free unreferenced glob pointers
318
f84fe999 319(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 320
7d5b40b4 321=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 322
8f7e4d2c 323(S internal) Perl went to decrement the reference count of a scalar to
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324see if it would go to 0, and discovered that it had already gone to 0
325earlier, and should have been freed, and in fact, probably was freed.
326This could indicate that SvREFCNT_dec() was called too many times, or
327that SvREFCNT_inc() was called too few times, or that the SV was
328mortalized when it shouldn't have been, or that memory has been
329corrupted.
a0d0e21e 330
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331=item Attempt to pack pointer to temporary value
332
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333(W pack) You tried to pass a temporary value (like the result of a
334function, or a computed expression) to the "p" pack() template. This
335means the result contains a pointer to a location that could become
336invalid anytime, even before the end of the current statement. Use
337literals or global values as arguments to the "p" pack() template to
338avoid this warning.
84902520 339
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340=item Attempt to reload %s aborted.
341
342(F) You tried to load a file with C<use> or C<require> that failed to
343compile once already. Perl will not try to compile this file again
344unless you delete its entry from %INC. See L<perlfunc/require> and
345L<perlvar/%INC>.
346
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347=item Attempt to set length of freed array
348
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349(W misc) You tried to set the length of an array which has
350been freed. You can do this by storing a reference to the
351scalar representing the last index of an array and later
352assigning through that reference. For example
1b20cd17
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353
354 $r = do {my @a; \$#a};
355 $$r = 503
356
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357=item Attempt to use reference as lvalue in substr
358
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359(W substr) You supplied a reference as the first argument to substr()
360used as an lvalue, which is pretty strange. Perhaps you forgot to
361dereference it first. See L<perlfunc/substr>.
b7a902f4 362
c32124fe
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363=item Attribute "locked" is deprecated
364
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365(D deprecated) You have used the attributes pragma to modify the
366"locked" attribute on a code reference. The :locked attribute is
367obsolete, has had no effect since 5005 threads were removed, and
368will be removed in a future release of Perl 5.
c32124fe 369
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370=item Attribute prototype(%s) discards earlier prototype attribute in same sub
371
372(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
373example. Since each sub can only have one prototype, the earlier
374declaration(s) are discarded while the last one is applied.
375
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376=item Attribute "unique" is deprecated
377
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378(D deprecated) You have used the attributes pragma to modify
379the "unique" attribute on an array, hash or scalar reference.
380The :unique attribute has had no effect since Perl 5.8.8, and
381will be removed in a future release of Perl 5.
f1a3ce43 382
ccce04a4
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383=item av_reify called on tied array
384
385(S debugging) This indicates that something went wrong and Perl got I<very>
386confused about C<@_> or C<@DB::args> being tied.
387
de42a5a9 388=item Bad arg length for %s, is %u, should be %d
a0d0e21e 389
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390(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
391or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 392S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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393S<sizeof(struct shmid_ds *)>.
394
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395=item Bad evalled substitution pattern
396
496a33f5 397(F) You've used the C</e> switch to evaluate the replacement for a
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398substitution, but perl found a syntax error in the code to evaluate,
399most likely an unexpected right brace '}'.
400
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401=item Bad filehandle: %s
402
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403(F) A symbol was passed to something wanting a filehandle, but the
404symbol has no filehandle associated with it. Perhaps you didn't do an
405open(), or did it in another package.
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406
407=item Bad free() ignored
408
be771a83 409(S malloc) An internal routine called free() on something that had never
fa816bf3 410been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 411setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 412
9ea8bc6d 413This message can be seen quite often with DB_File on systems with "hard"
6903afa2 414dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 415which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 416
aa689395
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417=item Bad hash
418
419(P) One of the internal hash routines was passed a null HV pointer.
420
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421=item Badly placed ()'s
422
423(A) You've accidentally run your script through B<csh> instead
424of Perl. Check the #! line, or manually feed your script into
425Perl yourself.
426
a7cb8dae 427=item Bad name after %s
a0d0e21e 428
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429(F) You started to name a symbol by using a package prefix, and then
430didn't finish the symbol. In particular, you can't interpolate outside
431of quotes, so
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432
433 $var = 'myvar';
434 $sym = mypack::$var;
435
436is not the same as
437
438 $var = 'myvar';
439 $sym = "mypack::$var";
440
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441=item Bad plugin affecting keyword '%s'
442
443(F) An extension using the keyword plugin mechanism violated the
444plugin API.
445
4ad56ec9
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446=item Bad realloc() ignored
447
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448(S malloc) An internal routine called realloc() on something that
449had never been malloc()ed in the first place. Mandatory, but can
450be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 451
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452=item Bad symbol for array
453
454(P) An internal request asked to add an array entry to something that
455wasn't a symbol table entry.
456
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457=item Bad symbol for dirhandle
458
459(P) An internal request asked to add a dirhandle entry to something
460that wasn't a symbol table entry.
461
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462=item Bad symbol for filehandle
463
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464(P) An internal request asked to add a filehandle entry to something
465that wasn't a symbol table entry.
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466
467=item Bad symbol for hash
468
469(P) An internal request asked to add a hash entry to something that
470wasn't a symbol table entry.
471
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472=item Bareword found in conditional
473
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474(W bareword) The compiler found a bareword where it expected a
475conditional, which often indicates that an || or && was parsed as part
476of the last argument of the previous construct, for example:
34d09196
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477
478 open FOO || die;
479
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480It may also indicate a misspelled constant that has been interpreted as
481a bareword:
34d09196
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482
483 use constant TYPO => 1;
484 if (TYOP) { print "foo" }
485
486The C<strict> pragma is useful in avoiding such errors.
487
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488=item Bareword "%s" not allowed while "strict subs" in use
489
490(F) With "strict subs" in use, a bareword is only allowed as a
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491subroutine identifier, in curly brackets or to the left of the "=>"
492symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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493
494=item Bareword "%s" refers to nonexistent package
495
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496(W bareword) You used a qualified bareword of the form C<Foo::>, but the
497compiler saw no other uses of that namespace before that point. Perhaps
498you need to predeclare a package?
6df41af2 499
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500=item BEGIN failed--compilation aborted
501
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502(F) An untrapped exception was raised while executing a BEGIN
503subroutine. Compilation stops immediately and the interpreter is
504exited.
a0d0e21e 505
68dc0745
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506=item BEGIN not safe after errors--compilation aborted
507
508(F) Perl found a C<BEGIN {}> subroutine (or a C<use> directive, which
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509implies a C<BEGIN {}>) after one or more compilation errors had already
510occurred. Since the intended environment for the C<BEGIN {}> could not
511be guaranteed (due to the errors), and since subsequent code likely
512depends on its correct operation, Perl just gave up.
68dc0745 513
c782d7ee 514=item \%d better written as $%d
6df41af2 515
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516(W syntax) Outside of patterns, backreferences live on as variables.
517The use of backslashes is grandfathered on the right-hand side of a
518substitution, but stylistically it's better to use the variable form
519because other Perl programmers will expect it, and it works better if
520there are more than 9 backreferences.
6df41af2 521
252aa082
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522=item Binary number > 0b11111111111111111111111111111111 non-portable
523
e476b1b5 524(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
525(4294967295) and therefore non-portable between systems. See
526L<perlport> for more on portability concerns.
252aa082 527
69282e91 528=item bind() on closed socket %s
a0d0e21e 529
be771a83
GS
530(W closed) You tried to do a bind on a closed socket. Did you forget to
531check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 532
c289d2f7
JH
533=item binmode() on closed filehandle %s
534
535(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 536Check your control flow and number of arguments.
c289d2f7 537
c5a0f51a
JH
538=item Bit vector size > 32 non-portable
539
e476b1b5 540(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 541
043c750c 542=item Bizarre copy of %s
4633a7c4 543
be771a83 544(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 545copiable.
4633a7c4 546
5a25739d
FC
547=item Bizarre SvTYPE [%d]
548
434f489b 549(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
550encountered an invalid data type.
551
f675dbe5
CB
552=item Buffer overflow in prime_env_iter: %s
553
be771a83
GS
554(W internal) A warning peculiar to VMS. While Perl was preparing to
555iterate over %ENV, it encountered a logical name or symbol definition
556which was too long, so it was truncated to the string shown.
f675dbe5 557
a0d0e21e
LW
558=item Callback called exit
559
4929bf7b 560(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
561exited by calling exit.
562
6df41af2 563=item %s() called too early to check prototype
f675dbe5 564
be771a83
GS
565(W prototype) You've called a function that has a prototype before the
566parser saw a definition or declaration for it, and Perl could not check
567that the call conforms to the prototype. You need to either add an
568early prototype declaration for the subroutine in question, or move the
569subroutine definition ahead of the call to get proper prototype
570checking. Alternatively, if you are certain that you're calling the
571function correctly, you may put an ampersand before the name to avoid
572the warning. See L<perlsub>.
f675dbe5 573
56feebad
FC
574=item Calling POSIX::%s() is deprecated
575
576(D deprecated) You called a function whose use is deprecated. See
577the function's name in L<POSIX> for details.
578
0c7df902
JH
579=item Cannot chr %f
580
581(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
582
5dee29d4 583=item Cannot compress %f in pack
0c7df902 584
5dee29d4
JH
585(F) You tried compressing an infinity or not-a-number as an unsigned
586integer with BER, which makes no sense.
0c7df902 587
49704364 588=item Cannot compress integer in pack
0258719b 589
717feafc
JH
590(F) An argument to pack("w",...) was too large to compress.
591The BER compressed integer format can only be used with positive
592integers, and you attempted to compress a very large number (> 1e308).
593See L<perlfunc/pack>.
0258719b 594
49704364 595=item Cannot compress negative numbers in pack
0258719b
NC
596
597(F) An argument to pack("w",...) was negative. The BER compressed integer
598format can only be used with positive integers. See L<perlfunc/pack>.
599
5c1f4d79
NC
600=item Cannot convert a reference to %s to typeglob
601
6903afa2
FC
602(F) You manipulated Perl's symbol table directly, stored a reference
603in it, then tried to access that symbol via conventional Perl syntax.
604The access triggers Perl to autovivify that typeglob, but it there is
605no legal conversion from that type of reference to a typeglob.
5c1f4d79 606
4040665a 607=item Cannot copy to %s
ba2fdce6
NC
608
609(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 610be directly assigned to.
ba2fdce6 611
b5d97229
RGS
612=item Cannot find encoding "%s"
613
614(S io) You tried to apply an encoding that did not exist to a filehandle,
615either with open() or binmode().
616
0c7df902
JH
617=item Cannot pack %f with '%c'
618
5dee29d4 619(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
620which makes no sense.
621
622=item Cannot printf %f with '%c'
623
624(F) You tried printing an infinity or not-a-number as a character (%c),
625which makes no sense. Maybe you meant '%s', or just stringifying it?
626
7355df7e
FC
627=item Cannot set tied @DB::args
628
629(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
630is not supported. (Before this error was added, it used to crash.)
631
ce65bc73
FC
632=item Cannot tie unreifiable array
633
634(P) You somehow managed to call C<tie> on an array that does not
635keep a reference count on its arguments and cannot be made to
636do so. Such arrays are not even supposed to be accessible to
637Perl code, but are only used internally.
638
96ebfdd7
RK
639=item Can only compress unsigned integers in pack
640
641(F) An argument to pack("w",...) was not an integer. The BER compressed
642integer format can only be used with positive integers, and you attempted
643to compress something else. See L<perlfunc/pack>.
644
a0d0e21e
LW
645=item Can't bless non-reference value
646
647(F) Only hard references may be blessed. This is how Perl "enforces"
648encapsulation of objects. See L<perlobj>.
649
dc57907a
RGS
650=item Can't "break" in a loop topicalizer
651
0d863452 652(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 653a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
654
655=item Can't "break" outside a given block
dc57907a 656
0d863452
RH
657(F) You called C<break>, but you're not inside a C<given> block.
658
6df41af2
GS
659=item Can't call method "%s" on an undefined value
660
661(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
662object reference or package name contains an undefined value. Something
663like this will reproduce the error:
6df41af2
GS
664
665 $BADREF = undef;
666 process $BADREF 1,2,3;
667 $BADREF->process(1,2,3);
668
a0d0e21e
LW
669=item Can't call method "%s" on unblessed reference
670
54310121 671(F) A method call must know in what package it's supposed to run. It
be771a83
GS
672ordinarily finds this out from the object reference you supply, but you
673didn't supply an object reference in this case. A reference isn't an
674object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
675
676=item Can't call method "%s" without a package or object reference
677
678(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
679object reference or package name contains an expression that returns a
680defined value which is neither an object reference nor a package name.
72b5445b
GS
681Something like this will reproduce the error:
682
683 $BADREF = 42;
684 process $BADREF 1,2,3;
685 $BADREF->process(1,2,3);
686
dfe378f1
FC
687=item Can't call mro_isa_changed_in() on anonymous symbol table
688
689(P) Perl got confused as to whether a hash was a plain hash or a
690symbol table hash when trying to update @ISA caches.
691
2bf7e7b2
FC
692=item Can't call mro_method_changed_in() on anonymous symbol table
693
694(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
695not attached to the symbol table.
696
a0d0e21e
LW
697=item Can't chdir to %s
698
f703fc96 699(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
700that you can chdir to, possibly because it doesn't exist.
701
0545a864 702=item Can't check filesystem of script "%s" for nosuid
104d25b7 703
be771a83
GS
704(P) For some reason you can't check the filesystem of the script for
705nosuid.
104d25b7 706
22e74366 707=item Can't coerce %s to %s in %s
a0d0e21e
LW
708
709(F) Certain types of SVs, in particular real symbol table entries
55497cff 710(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
711say things like:
712
713 *foo += 1;
714
715You CAN say
716
717 $foo = *foo;
718 $foo += 1;
719
720but then $foo no longer contains a glob.
721
0d863452 722=item Can't "continue" outside a when block
dc57907a 723
0d863452
RH
724(F) You called C<continue>, but you're not inside a C<when>
725or C<default> block.
726
a0d0e21e
LW
727=item Can't create pipe mailbox
728
be771a83
GS
729(P) An error peculiar to VMS. The process is suffering from exhausted
730quotas or other plumbing problems.
a0d0e21e 731
eb64745e
GS
732=item Can't declare %s in "%s"
733
30c282f6
NC
734(F) Only scalar, array, and hash variables may be declared as "my", "our" or
735"state" variables. They must have ordinary identifiers as names.
a0d0e21e 736
fc7debfb
FC
737=item Can't "default" outside a topicalizer
738
739(F) You have used a C<default> block that is neither inside a
740C<foreach> loop nor a C<given> block. (Note that this error is
741issued on exit from the C<default> block, so you won't get the
742error if you use an explicit C<continue>.)
743
6df41af2
GS
744=item Can't do inplace edit: %s is not a regular file
745
be771a83 746(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 747a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 748
a0d0e21e
LW
749=item Can't do inplace edit on %s: %s
750
be771a83
GS
751(S inplace) The creation of the new file failed for the indicated
752reason.
a0d0e21e 753
54310121 754=item Can't do inplace edit without backup
a0d0e21e 755
be771a83
GS
756(F) You're on a system such as MS-DOS that gets confused if you try
757reading from a deleted (but still opened) file. You have to say
758C<-i.bak>, or some such.
a0d0e21e 759
10f9c03d 760=item Can't do inplace edit: %s would not be unique
a0d0e21e 761
e476b1b5 762(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
763characters and Perl was unable to create a unique filename during
764inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 765
a0d0e21e
LW
766=item Can't do waitpid with flags
767
be771a83
GS
768(F) This machine doesn't have either waitpid() or wait4(), so only
769waitpid() without flags is emulated.
a0d0e21e 770
a0d0e21e
LW
771=item Can't emulate -%s on #! line
772
be771a83
GS
773(F) The #! line specifies a switch that doesn't make sense at this
774point. For example, it'd be kind of silly to put a B<-x> on the #!
775line.
a0d0e21e 776
1109a392
MHM
777=item Can't %s %s-endian %ss on this platform
778
779(F) Your platform's byte-order is neither big-endian nor little-endian,
780or it has a very strange pointer size. Packing and unpacking big- or
781little-endian floating point values and pointers may not be possible.
782See L<perlfunc/pack>.
783
a0d0e21e
LW
784=item Can't exec "%s": %s
785
d1be9408 786(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
787named program for the indicated reason. Typical reasons include: the
788permissions were wrong on the file, the file wasn't found in
789C<$ENV{PATH}>, the executable in question was compiled for another
790architecture, or the #! line in a script points to an interpreter that
791can't be run for similar reasons. (Or maybe your system doesn't support
792#! at all.)
a0d0e21e
LW
793
794=item Can't exec %s
795
be771a83
GS
796(F) Perl was trying to execute the indicated program for you because
797that's what the #! line said. If that's not what you wanted, you may
798need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
799
800=item Can't execute %s
801
be771a83
GS
802(F) You used the B<-S> switch, but the copies of the script to execute
803found in the PATH did not have correct permissions.
2a92aaa0 804
6df41af2 805=item Can't find an opnumber for "%s"
2a92aaa0 806
be771a83
GS
807(F) A string of a form C<CORE::word> was given to prototype(), but there
808is no builtin with the name C<word>.
6df41af2 809
56ca2fc0
JH
810=item Can't find %s character property "%s"
811
812(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 813could not be found. Maybe you misspelled the name of the property?
e1b711da 814See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 815for a complete list of available official properties.
56ca2fc0 816
6df41af2
GS
817=item Can't find label %s
818
be771a83
GS
819(F) You said to goto a label that isn't mentioned anywhere that it's
820possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
821
822=item Can't find %s on PATH
823
be771a83
GS
824(F) You used the B<-S> switch, but the script to execute could not be
825found in the PATH.
a0d0e21e 826
6df41af2 827=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 828
be771a83
GS
829(F) You used the B<-S> switch, but the script to execute could not be
830found in the PATH, or at least not with the correct permissions. The
831script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
832
833=item Can't find string terminator %s anywhere before EOF
834
be771a83
GS
835(F) Perl strings can stretch over multiple lines. This message means
836that the closing delimiter was omitted. Because bracketed quotes count
837nesting levels, the following is missing its final parenthesis:
a0d0e21e 838
fb73857a
PP
839 print q(The character '(' starts a side comment.);
840
97b3d10f 841If you're getting this error from a here-document, you may have
b6b8cb97
FC
842included unseen whitespace before or after your closing tag or there
843may not be a linebreak after it. A good programmer's editor will have
844a way to help you find these characters (or lack of characters). See
845L<perlop> for the full details on here-documents.
a0d0e21e 846
660a4616
ST
847=item Can't find Unicode property definition "%s"
848
5f8ad6b6
FC
849(F) You may have tried to use C<\p> which means a Unicode
850property (for example C<\p{Lu}> matches all uppercase
fa816bf3 851letters). If you did mean to use a Unicode property, see
e1b711da 852L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 853for a complete list of available properties. If you didn't
fa816bf3
FC
854mean to use a Unicode property, escape the C<\p>, either by
855C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 856until C<\E>).
660a4616 857
b3647a36 858=item Can't fork: %s
a0d0e21e 859
be771a83
GS
860(F) A fatal error occurred while trying to fork while opening a
861pipeline.
a0d0e21e 862
b3647a36
SR
863=item Can't fork, trying again in 5 seconds
864
c973c02e 865(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
866after five seconds.
867
748a9306
LW
868=item Can't get filespec - stale stat buffer?
869
be771a83
GS
870(S) A warning peculiar to VMS. This arises because of the difference
871between access checks under VMS and under the Unix model Perl assumes.
872Under VMS, access checks are done by filename, rather than by bits in
873the stat buffer, so that ACLs and other protections can be taken into
874account. Unfortunately, Perl assumes that the stat buffer contains all
875the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 876the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
877the device name and FID present in the stat buffer, but this works only
878if you haven't made a subsequent call to the CRTL stat() routine,
879because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
880appears, the name lookup failed, and the access-checking routine gave up
881and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
882routine knows about the Perl C<stat> operator and file tests, so you
883shouldn't ever see this warning in response to a Perl command; it arises
884only if some internal code takes stat buffers lightly.)
748a9306 885
a0d0e21e
LW
886=item Can't get pipe mailbox device name
887
be771a83
GS
888(P) An error peculiar to VMS. After creating a mailbox to act as a
889pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
890
891=item Can't get SYSGEN parameter value for MAXBUF
892
748a9306
LW
893(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
894mailbox buffers to be, and didn't get an answer.
a0d0e21e 895
6df41af2 896=item Can't "goto" into the middle of a foreach loop
a0d0e21e 897
be771a83
GS
898(F) A "goto" statement was executed to jump into the middle of a foreach
899loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
900
901=item Can't "goto" out of a pseudo block
902
be771a83
GS
903(F) A "goto" statement was executed to jump out of what might look like
904a block, except that it isn't a proper block. This usually occurs if
905you tried to jump out of a sort() block or subroutine, which is a no-no.
906See L<perlfunc/goto>.
a0d0e21e 907
5a25739d
FC
908=item Can't goto subroutine from an eval-%s
909
910(F) The "goto subroutine" call can't be used to jump out of an eval
911"string" or block.
912
9850bf21 913=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 914
9850bf21
RH
915(F) The "goto subroutine" call can't be used to jump out of the
916comparison sub for a sort(), or from a similar callback (such
917as the reduce() function in List::Util).
918
6df41af2
GS
919=item Can't goto subroutine outside a subroutine
920
be771a83
GS
921(F) The deeply magical "goto subroutine" call can only replace one
922subroutine call for another. It can't manufacture one out of whole
923cloth. In general you should be calling it out of only an AUTOLOAD
924routine anyway. See L<perlfunc/goto>.
6df41af2 925
0b5b802d
GS
926=item Can't ignore signal CHLD, forcing to default
927
be771a83
GS
928(W signal) Perl has detected that it is being run with the SIGCHLD
929signal (sometimes known as SIGCLD) disabled. Since disabling this
930signal will interfere with proper determination of exit status of child
931processes, Perl has reset the signal to its default value. This
932situation typically indicates that the parent program under which Perl
933may be running (e.g. cron) is being very careless.
0b5b802d 934
e2c0f81f
DG
935=item Can't kill a non-numeric process ID
936
937(F) Process identifiers must be (signed) integers. It is a fatal error to
938attempt to kill() an undefined, empty-string or otherwise non-numeric
939process identifier.
940
6df41af2 941=item Can't "last" outside a loop block
4633a7c4 942
6df41af2 943(F) A "last" statement was executed to break out of the current block,
be771a83
GS
944except that there's this itty bitty problem called there isn't a current
945block. Note that an "if" or "else" block doesn't count as a "loopish"
946block, as doesn't a block given to sort(), map() or grep(). You can
947usually double the curlies to get the same effect though, because the
948inner curlies will be considered a block that loops once. See
949L<perlfunc/last>.
4633a7c4 950
2c7d6b9c
RGS
951=item Can't linearize anonymous symbol table
952
953(F) Perl tried to calculate the method resolution order (MRO) of a
954package, but failed because the package stash has no name.
955
b8170e59
JB
956=item Can't load '%s' for module %s
957
6903afa2
FC
958(F) The module you tried to load failed to load a dynamic extension.
959This may either mean that you upgraded your version of perl to one
960that is incompatible with your old dynamic extensions (which is known
961to happen between major versions of perl), or (more likely) that your
962dynamic extension was built against an older version of the library
963that is installed on your system. You may need to rebuild your old
964dynamic extensions.
b8170e59 965
748a9306
LW
966=item Can't localize lexical variable %s
967
2ba9eb46 968(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
969lexical variable using "my" or "state". This is not allowed. If you
970want to localize a package variable of the same name, qualify it with
971the package name.
748a9306 972
6df41af2 973=item Can't localize through a reference
4727527e 974
6df41af2
GS
975(F) You said something like C<local $$ref>, which Perl can't currently
976handle, because when it goes to restore the old value of whatever $ref
be771a83 977pointed to after the scope of the local() is finished, it can't be sure
64977eb6 978that $ref will still be a reference.
4727527e 979
ea071790 980=item Can't locate %s
ec889f3a 981
fa816bf3
FC
982(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
983Perl looks for the file in all the locations mentioned in @INC, unless
984the file name included the full path to the file. Perhaps you need
985to set the PERL5LIB or PERL5OPT environment variable to say where the
986extra library is, or maybe the script needs to add the library name
be771a83
GS
987to @INC. Or maybe you just misspelled the name of the file. See
988L<perlfunc/require> and L<lib>.
a0d0e21e 989
6df41af2
GS
990=item Can't locate auto/%s.al in @INC
991
be771a83
GS
992(F) A function (or method) was called in a package which allows
993autoload, but there is no function to autoload. Most probable causes
994are a misprint in a function/method name or a failure to C<AutoSplit>
995the file, say, by doing C<make install>.
6df41af2 996
b8170e59
JB
997=item Can't locate loadable object for module %s in @INC
998
999(F) The module you loaded is trying to load an external library, like
d70d8e57 1000for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1001unable to locate this library. See L<DynaLoader>.
1002
a0d0e21e
LW
1003=item Can't locate object method "%s" via package "%s"
1004
1005(F) You called a method correctly, and it correctly indicated a package
1006functioning as a class, but that package doesn't define that particular
2ba9eb46 1007method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1008
8af56b9d
FC
1009=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1010to load "%s"?)
1011
1012(F) You called a method on a class that did not exist, and the method
1013could not be found in UNIVERSAL. This often means that a method
1014requires a package that has not been loaded.
1015
a0d0e21e
LW
1016=item Can't locate package %s for @%s::ISA
1017
be771a83
GS
1018(W syntax) The @ISA array contained the name of another package that
1019doesn't seem to exist.
a0d0e21e 1020
2f7da168
RK
1021=item Can't locate PerlIO%s
1022
1023(F) You tried to use in open() a PerlIO layer that does not exist,
1024e.g. open(FH, ">:nosuchlayer", "somefile").
1025
f4ad53f4 1026=item Can't make list assignment to %ENV on this system
3e3baf6d 1027
be771a83
GS
1028(F) List assignment to %ENV is not supported on some systems, notably
1029VMS.
3e3baf6d 1030
cd40cd58
NC
1031=item Can't make loaded symbols global on this platform while loading %s
1032
ff9c1ae8 1033(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1034that symbols from the stated file are made available globally within the
1035process, but that functionality is not available on this platform. Whilst
1036the module likely will still work, this may prevent the perl interpreter
1037from loading other XS-based extensions which need to link directly to
1038functions defined in the C or XS code in the stated file.
1039
a0d0e21e
LW
1040=item Can't modify %s in %s
1041
be771a83
GS
1042(F) You aren't allowed to assign to the item indicated, or otherwise try
1043to change it, such as with an auto-increment.
a0d0e21e 1044
54310121 1045=item Can't modify nonexistent substring
a0d0e21e
LW
1046
1047(P) The internal routine that does assignment to a substr() was handed
1048a NULL.
1049
6df41af2
GS
1050=item Can't modify non-lvalue subroutine call
1051
1052(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1053such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1054
5f05dabc 1055=item Can't msgrcv to read-only var
a0d0e21e 1056
5f05dabc 1057(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1058buffer.
1059
6df41af2
GS
1060=item Can't "next" outside a loop block
1061
1062(F) A "next" statement was executed to reiterate the current block, but
1063there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1064count as a "loopish" block, as doesn't a block given to sort(), map() or
1065grep(). You can usually double the curlies to get the same effect
1066though, because the inner curlies will be considered a block that loops
1067once. See L<perlfunc/next>.
6df41af2 1068
a0d0e21e
LW
1069=item Can't open %s: %s
1070
c47ff5f1 1071(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1072filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1073switches, or explicitly, failed for the indicated reason. Usually
1074this is because you don't have read permission for a file which
1075you named on the command line.
1076
1077(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1078your operating system's equivalent) could not be opened.
a0d0e21e 1079
9a869a14
RGS
1080=item Can't open a reference
1081
1082(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1083using the 3-arg open() syntax:
9a869a14
RGS
1084
1085 open FH, '>', $ref;
1086
1087but your version of perl is compiled without perlio, and this form of
1088open is not supported.
1089
a0d0e21e
LW
1090=item Can't open bidirectional pipe
1091
be771a83
GS
1092(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1093You can try any of several modules in the Perl library to do this, such
1094as IPC::Open2. Alternately, direct the pipe's output to a file using
1095">", and then read it in under a different file handle.
a0d0e21e 1096
748a9306
LW
1097=item Can't open error file %s as stderr
1098
be771a83
GS
1099(F) An error peculiar to VMS. Perl does its own command line
1100redirection, and couldn't open the file specified after '2>' or '2>>' on
1101the command line for writing.
748a9306
LW
1102
1103=item Can't open input file %s as stdin
1104
be771a83
GS
1105(F) An error peculiar to VMS. Perl does its own command line
1106redirection, and couldn't open the file specified after '<' on the
1107command line for reading.
748a9306
LW
1108
1109=item Can't open output file %s as stdout
1110
be771a83
GS
1111(F) An error peculiar to VMS. Perl does its own command line
1112redirection, and couldn't open the file specified after '>' or '>>' on
1113the command line for writing.
748a9306
LW
1114
1115=item Can't open output pipe (name: %s)
1116
be771a83
GS
1117(P) An error peculiar to VMS. Perl does its own command line
1118redirection, and couldn't open the pipe into which to send data destined
1119for stdout.
748a9306 1120
3b1cf97d 1121=item Can't open perl script "%s": %s
a0d0e21e
LW
1122
1123(F) The script you specified can't be opened for the indicated reason.
1124
fa3aa65a
JC
1125If you're debugging a script that uses #!, and normally relies on the
1126shell's $PATH search, the -S option causes perl to do that search, so
1127you don't have to type the path or C<`which $scriptname`>.
1128
6df41af2
GS
1129=item Can't read CRTL environ
1130
1131(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1132from the CRTL's internal environment array and discovered the array was
1133missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1134or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1135searched.
6df41af2 1136
6df41af2
GS
1137=item Can't "redo" outside a loop block
1138
1139(F) A "redo" statement was executed to restart the current block, but
1140there isn't a current block. Note that an "if" or "else" block doesn't
1141count as a "loopish" block, as doesn't a block given to sort(), map()
1142or grep(). You can usually double the curlies to get the same effect
1143though, because the inner curlies will be considered a block that
1144loops once. See L<perlfunc/redo>.
1145
64977eb6 1146=item Can't remove %s: %s, skipping file
10f9c03d 1147
be771a83
GS
1148(S inplace) You requested an inplace edit without creating a backup
1149file. Perl was unable to remove the original file to replace it with
1150the modified file. The file was left unmodified.
10f9c03d 1151
a0d0e21e
LW
1152=item Can't rename %s to %s: %s, skipping file
1153
e476b1b5 1154(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1155probably because you don't have write permission to the directory.
a0d0e21e 1156
748a9306
LW
1157=item Can't reopen input pipe (name: %s) in binary mode
1158
be771a83
GS
1159(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1160to reopen it to accept binary data. Alas, it failed.
748a9306 1161
4f12ec0e
FC
1162=item Can't reset %ENV on this system
1163
1164(F) You called C<reset('E')> or similar, which tried to reset
1165all variables in the current package beginning with "E". In
1166the main package, that includes %ENV. Resetting %ENV is not
1167supported on some systems, notably VMS.
1168
fe13d51d 1169=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1170
1fa582fa
FC
1171(F)(P) Error resolving overloading specified by a method name (as
1172opposed to a subroutine reference): no such method callable via the
1173package. If the method name is C<???>, this is an internal error.
6df41af2 1174
cd06dffe
GS
1175=item Can't return %s from lvalue subroutine
1176
be771a83
GS
1177(F) Perl detected an attempt to return illegal lvalues (such as
1178temporary or readonly values) from a subroutine used as an lvalue. This
1179is not allowed.
cd06dffe 1180
96ebfdd7
RK
1181=item Can't return outside a subroutine
1182
1183(F) The return statement was executed in mainline code, that is, where
1184there was no subroutine call to return out of. See L<perlsub>.
1185
78f9721b
SM
1186=item Can't return %s to lvalue scalar context
1187
6903afa2
FC
1188(F) You tried to return a complete array or hash from an lvalue
1189subroutine, but you called the subroutine in a way that made Perl
1190think you meant to return only one value. You probably meant to
1191write parentheses around the call to the subroutine, which tell
1192Perl that the call should be in list context.
78f9721b 1193
a0d0e21e
LW
1194=item Can't stat script "%s"
1195
be771a83
GS
1196(P) For some reason you can't fstat() the script even though you have it
1197open already. Bizarre.
a0d0e21e 1198
a0d0e21e
LW
1199=item Can't take log of %g
1200
fb73857a 1201(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1202negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1203standard with Perl, though, if you really want to do that for the
1204negative numbers.
a0d0e21e
LW
1205
1206=item Can't take sqrt of %g
1207
1208(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1209negative number. There's a Math::Complex package that comes standard
1210with Perl, though, if you really want to do that.
a0d0e21e
LW
1211
1212=item Can't undef active subroutine
1213
1214(F) You can't undefine a routine that's currently running. You can,
1215however, redefine it while it's running, and you can even undef the
1216redefined subroutine while the old routine is running. Go figure.
1217
c81225bc 1218=item Can't upgrade %s (%d) to %d
a0d0e21e 1219
be771a83
GS
1220(P) The internal sv_upgrade routine adds "members" to an SV, making it
1221into a more specialized kind of SV. The top several SV types are so
1222specialized, however, that they cannot be interconverted. This message
1223indicates that such a conversion was attempted.
a0d0e21e 1224
6651ba0b
FC
1225=item Can't use '%c' after -mname
1226
1227(F) You tried to call perl with the B<-m> switch, but you put something
1228other than "=" after the module name.
1229
1f1ec7b5
KW
1230=item Can't use a hash as a reference
1231
1232(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1233C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1234<= 5.22.0 used to allow this syntax, but shouldn't
1235have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1236
1237=item Can't use an array as a reference
1238
1239(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1240C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1241used to allow this syntax, but shouldn't have. This
1242was deprecated in perl 5.6.1.
1f1ec7b5 1243
1db89ea5
BS
1244=item Can't use anonymous symbol table for method lookup
1245
e27ad1f2 1246(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1247table that doesn't have a name. Symbol tables can become anonymous
1248for example by undefining stashes: C<undef %Some::Package::>.
1249
96ebfdd7
RK
1250=item Can't use an undefined value as %s reference
1251
1252(F) A value used as either a hard reference or a symbolic reference must
1253be a defined value. This helps to delurk some insidious errors.
1254
6df41af2
GS
1255=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1256
be771a83
GS
1257(F) Only hard references are allowed by "strict refs". Symbolic
1258references are disallowed. See L<perlref>.
6df41af2 1259
90b75b61 1260=item Can't use %! because Errno.pm is not available
1d2dff63 1261
20561843 1262(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1263Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1264provide symbolic names for C<$!> errno values.
1265
1109a392
MHM
1266=item Can't use both '<' and '>' after type '%c' in %s
1267
1268(F) A type cannot be forced to have both big-endian and little-endian
1269byte-order at the same time, so this combination of modifiers is not
1270allowed. See L<perlfunc/pack>.
1271
e35475de
KW
1272=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1273
1274(F) defined() is not useful on arrays because it
1275checks for an undefined I<scalar> value. If you want to see if the
1276array is empty, just use C<if (@array) { # not empty }> for example.
1277
1278=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1279
1280(F) C<defined()> is not usually right on hashes.
1281
1282Although C<defined %hash> is false on a plain not-yet-used hash, it
1283becomes true in several non-obvious circumstances, including iterators,
1284weak references, stash names, even remaining true after C<undef %hash>.
1285These things make C<defined %hash> fairly useless in practice, so it now
1286generates a fatal error.
1287
1288If a check for non-empty is what you wanted then just put it in boolean
1289context (see L<perldata/Scalar values>):
1290
1291 if (%hash) {
1292 # not empty
1293 }
1294
1295If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1296variable exists then that's never really been reliable, and isn't
1297a good way to enquire about the features of a package, or whether
1298it's loaded, etc.
1299
6df41af2
GS
1300=item Can't use %s for loop variable
1301
be771a83
GS
1302(F) Only a simple scalar variable may be used as a loop variable on a
1303foreach.
6df41af2 1304
aab6a793 1305=item Can't use global %s in "%s"
6df41af2 1306
be771a83
GS
1307(F) You tried to declare a magical variable as a lexical variable. This
1308is not allowed, because the magic can be tied to only one location
1309(namely the global variable) and it would be incredibly confusing to
1310have variables in your program that looked like magical variables but
6df41af2
GS
1311weren't.
1312
6d3b25aa
RGS
1313=item Can't use '%c' in a group with different byte-order in %s
1314
1315(F) You attempted to force a different byte-order on a type
1316that is already inside a group with a byte-order modifier.
1317For example you cannot force little-endianness on a type that
1318is inside a big-endian group.
1319
c07a80fd
PP
1320=item Can't use "my %s" in sort comparison
1321
1322(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1323You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1324and the variable had earlier been declared as a lexical variable.
1325Either qualify the sort variable with the package name, or rename the
1326lexical variable.
1327
a0d0e21e
LW
1328=item Can't use %s ref as %s ref
1329
1330(F) You've mixed up your reference types. You have to dereference a
1331reference of the type needed. You can use the ref() function to
1332test the type of the reference, if need be.
1333
748a9306 1334=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1335
5e634d20
FC
1336=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1337
b41bf23f
FC
1338(F) You've told Perl to dereference a string, something which
1339C<use strict> blocks to prevent it happening accidentally. See
1340L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1341in a double-quoted string immediately before interpolating a variable,
1342for example in C<"user @$twitter_id">, which says to treat the contents
1343of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1344symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1345
748a9306
LW
1346=item Can't use subscript on %s
1347
1348(F) The compiler tried to interpret a bracketed expression as a
1349subscript. But to the left of the brackets was an expression that
209e7cf1 1350didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1351
6df41af2
GS
1352=item Can't use \%c to mean $%c in expression
1353
75b44862
GS
1354(W syntax) In an ordinary expression, backslash is a unary operator that
1355creates a reference to its argument. The use of backslash to indicate a
1356backreference to a matched substring is valid only as part of a regular
be771a83
GS
1357expression pattern. Trying to do this in ordinary Perl code produces a
1358value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1359instead.
6df41af2 1360
810b8aa5
GS
1361=item Can't weaken a nonreference
1362
1363(F) You attempted to weaken something that was not a reference. Only
1364references can be weakened.
1365
fc7debfb
FC
1366=item Can't "when" outside a topicalizer
1367
1368(F) You have used a when() block that is neither inside a C<foreach>
1369loop nor a C<given> block. (Note that this error is issued on exit
1370from the C<when> block, so you won't get the error if the match fails,
1371or if you use an explicit C<continue>.)
1372
5f05dabc 1373=item Can't x= to read-only value
a0d0e21e 1374
be771a83
GS
1375(F) You tried to repeat a constant value (often the undefined value)
1376with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1377Perhaps you need to copy the value to a temporary, and repeat that.
1378
a04e6aad 1379=item Character following "\c" must be printable ASCII
f9d13529 1380
7357bd17 1381(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1382
727b6379 1383Note that ASCII characters that don't map to control characters are
7357bd17 1384discouraged, and will generate the warning (when enabled)
727b6379 1385L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1386
f337b084 1387=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1388
1389(W pack) You said
1390
1391 pack("C", $x)
1392
1393where $x is either less than 0 or more than 255; the C<"C"> format is
1394only for encoding native operating system characters (ASCII, EBCDIC,
1395and so on) and not for Unicode characters, so Perl behaved as if you meant
1396
1397 pack("C", $x & 255)
1398
1399If you actually want to pack Unicode codepoints, use the C<"U"> format
1400instead.
1401
f337b084 1402=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1403
1404(W pack) You said
1405
1406 pack("c", $x)
1407
1408where $x is either less than -128 or more than 127; the C<"c"> format
1409is only for encoding native operating system characters (ASCII, EBCDIC,
1410and so on) and not for Unicode characters, so Perl behaved as if you meant
1411
1412 pack("c", $x & 255);
1413
1414If you actually want to pack Unicode codepoints, use the C<"U"> format
1415instead.
1416
f337b084
TH
1417=item Character in '%c' format wrapped in unpack
1418
1419(W unpack) You tried something like
1420
1421 unpack("H", "\x{2a1}")
1422
1a147d38 1423where the format expects to process a byte (a character with a value
6903afa2
FC
1424below 256), but a higher value was provided instead. Perl uses the
1425value modulus 256 instead, as if you had provided:
f337b084
TH
1426
1427 unpack("H", "\x{a1}")
1428
5a25739d
FC
1429=item Character in 'W' format wrapped in pack
1430
1431(W pack) You said
1432
1433 pack("U0W", $x)
1434
1435where $x is either less than 0 or more than 255. However, C<U0>-mode
1436expects all values to fall in the interval [0, 255], so Perl behaved
1437as if you meant:
1438
1439 pack("U0W", $x & 255)
1440
f337b084
TH
1441=item Character(s) in '%c' format wrapped in pack
1442
1443(W pack) You tried something like
1444
1445 pack("u", "\x{1f3}b")
1446
1a147d38 1447where the format expects to process a sequence of bytes (character with a
6903afa2 1448value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1449uses the character values modulus 256 instead, as if you had provided:
1450
1451 pack("u", "\x{f3}b")
1452
1453=item Character(s) in '%c' format wrapped in unpack
1454
1455(W unpack) You tried something like
1456
1457 unpack("s", "\x{1f3}b")
1458
1a147d38 1459where the format expects to process a sequence of bytes (character with a
6903afa2 1460value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1461uses the character values modulus 256 instead, as if you had provided:
1462
1463 unpack("s", "\x{f3}b")
1464
f51551f7
FC
1465=item charnames alias definitions may not contain a sequence of multiple spaces
1466
1467(F) You defined a character name which had multiple space characters
1468in a row. Change them to single spaces. Usually these names are
1469defined in the C<:alias> import argument to C<use charnames>, but they
1470could be defined by a translator installed into C<$^H{charnames}>. See
1471L<charnames/CUSTOM ALIASES>.
1472
1473=item charnames alias definitions may not contain trailing white-space
1474
1475(F) You defined a character name which ended in a space
1476character. Remove the trailing space(s). Usually these names are
1477defined in the C<:alias> import argument to C<use charnames>, but they
1478could be defined by a translator installed into C<$^H{charnames}>.
1479See L<charnames/CUSTOM ALIASES>.
1480
1481=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1482
1483(D deprecated, regexp) The \C character class is deprecated, and will
1484become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1485v5.24). This construct allows you to match a single byte of what makes
1486up a multi-byte single UTF8 character, and breaks encapsulation. It is
1487currently also very buggy. If you really need to process the individual
f51551f7
FC
1488bytes, you probably want to convert your string to one where each
1489underlying byte is stored as a character, with utf8::encode().
1490
f866a7cd
FC
1491=item "\c%c" is more clearly written simply as "%s"
1492
1493(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1494non-printable characters. You used it for a printable one, which
1495is better written as simply itself, perhaps preceded by a backslash
1496for non-word characters. Doing it the way you did is not portable
1497between ASCII and EBCDIC platforms.
f866a7cd 1498
6651ba0b
FC
1499=item Cloning substitution context is unimplemented
1500
1501(F) Creating a new thread inside the C<s///> operator is not supported.
1502
abc7ecad
SP
1503=item closedir() attempted on invalid dirhandle %s
1504
1505(W io) The dirhandle you tried to close is either closed or not really
1506a dirhandle. Check your control flow.
1507
5a25739d
FC
1508=item close() on unopened filehandle %s
1509
1510(W unopened) You tried to close a filehandle that was never opened.
1511
541ed3a9
FC
1512=item Closure prototype called
1513
1514(F) If a closure has attributes, the subroutine passed to an attribute
1515handler is the prototype that is cloned when a new closure is created.
1516This subroutine cannot be called.
1517
49704364
LW
1518=item Code missing after '/'
1519
6903afa2
FC
1520(F) You had a (sub-)template that ends with a '/'. There must be
1521another template code following the slash. See L<perlfunc/pack>.
49704364 1522
5a25739d
FC
1523=item Code point 0x%X is not Unicode, may not be portable
1524
2d88a86a 1525(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1526of U+10FFFF.
1527
1528Perl allows strings to contain a superset of Unicode code points, up
1529to the limit of what is storable in an unsigned integer on your system,
1530but these may not be accepted by other languages/systems. At one time,
1531it was legal in some standards to have code points up to 0x7FFF_FFFF,
1532but not higher. Code points above 0xFFFF_FFFF require larger than a
153332 bit word.
0876b9a0 1534
6df41af2
GS
1535=item %s: Command not found
1536
a892b81a 1537(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1538instead of Perl. Check the #! line, or manually feed your script into
1539Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1540
1541 #!/usr/bin/perl -w
6df41af2 1542
7a2e2cd6
PP
1543=item Compilation failed in require
1544
1545(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1546Perl uses this generic message when none of the errors that it
1547encountered were severe enough to halt compilation immediately.
7a2e2cd6 1548
c3464db5
DD
1549=item Complex regular subexpression recursion limit (%d) exceeded
1550
be771a83
GS
1551(W regexp) The regular expression engine uses recursion in complex
1552situations where back-tracking is required. Recursion depth is limited
1553to 32766, or perhaps less in architectures where the stack cannot grow
1554arbitrarily. ("Simple" and "medium" situations are handled without
1555recursion and are not subject to a limit.) Try shortening the string
1556under examination; looping in Perl code (e.g. with C<while>) rather than
1557in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1558that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1559on I<Mastering Regular Expressions>.)
c3464db5 1560
69282e91 1561=item connect() on closed socket %s
a0d0e21e 1562
be771a83
GS
1563(W closed) You tried to do a connect on a closed socket. Did you forget
1564to check the return value of your socket() call? See
1565L<perlfunc/connect>.
a0d0e21e 1566
e21e7c6a
FC
1567=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1568
1569(F) The subroutine registered to handle constant overloading
1570(see L<overload>) or a custom charnames handler (see
1571L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1572
1573=item Constant(%s): $^H{%s} is not defined
1574
1575(F) The parser found inconsistencies while attempting to define an
1576overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1577L<overload> pragma?
e21e7c6a 1578
779c5bc9
GS
1579=item Constant is not %s reference
1580
1581(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1582is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1583The message indicates the type of reference that was expected. This
be771a83 1584usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1585See L<perlsub/"Constant Functions"> and L<constant>.
1586
4cee8e80
CS
1587=item Constant subroutine %s redefined
1588
aeb94125
FC
1589(W redefine)(S) You redefined a subroutine which had previously
1590been eligible for inlining. See L<perlsub/"Constant Functions">
1591for commentary and workarounds.
4cee8e80 1592
9607fc9c
PP
1593=item Constant subroutine %s undefined
1594
be771a83
GS
1595(W misc) You undefined a subroutine which had previously been eligible
1596for inlining. See L<perlsub/"Constant Functions"> for commentary and
1597workarounds.
9607fc9c 1598
5a25739d
FC
1599=item Constant(%s) unknown
1600
1601(F) The parser found inconsistencies either while attempting
1602to define an overloaded constant, or when trying to find the
1603character name specified in the C<\N{...}> escape. Perhaps you
1604forgot to load the corresponding L<overload> pragma?.
1605
e7ea3e70
IZ
1606=item Copy method did not return a reference
1607
6903afa2 1608(F) The method which overloads "=" is buggy. See
13a2d996 1609L<overload/Copy Constructor>.
e7ea3e70 1610
4aaa4757
FC
1611=item &CORE::%s cannot be called directly
1612
1613(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1614with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1615in this package cannot yet be called that way, but must be
1616called as barewords. Something like this will work:
1617
1618 BEGIN { *shove = \&CORE::push; }
1619 shove @array, 1,2,3; # pushes on to @array
1620
6798c92b
GS
1621=item CORE::%s is not a keyword
1622
1623(F) The CORE:: namespace is reserved for Perl keywords.
1624
675fa9ff
FC
1625=item Corrupted regexp opcode %d > %d
1626
1627(P) This is either an error in Perl, or, if you're using
1628one, your L<custom regular expression engine|perlreapi>. If not the
1629latter, report the problem through the L<perlbug> utility.
1630
a0d0e21e
LW
1631=item corrupted regexp pointers
1632
1633(P) The regular expression engine got confused by what the regular
1634expression compiler gave it.
1635
1636=item corrupted regexp program
1637
be771a83
GS
1638(P) The regular expression engine got passed a regexp program without a
1639valid magic number.
a0d0e21e 1640
de42a5a9 1641=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1642
1643(P) The malloc package that comes with Perl had an internal failure.
1644
49704364
LW
1645=item Count after length/code in unpack
1646
1647(F) You had an unpack template indicating a counted-length string, but
1648you have also specified an explicit size for the string. See
1649L<perlfunc/pack>.
1650
f2cccb4c
KW
1651=for comment
1652The following are used in lib/diagnostics.t for testing two =items that
1653share the same description. Changes here need to be propagated to there
1654
6651ba0b
FC
1655=item Deep recursion on anonymous subroutine
1656
a0d0e21e
LW
1657=item Deep recursion on subroutine "%s"
1658
be771a83
GS
1659(W recursion) This subroutine has called itself (directly or indirectly)
1660100 times more than it has returned. This probably indicates an
1661infinite recursion, unless you're writing strange benchmark programs, in
1662which case it indicates something else.
a0d0e21e 1663
aad1d01f
NC
1664This threshold can be changed from 100, by recompiling the F<perl> binary,
1665setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1666
e0e4a6e3
FC
1667=item (?(DEFINE)....) does not allow branches in regex; marked by
1668S<<-- HERE> in m/%s/
bcb95744 1669
6903afa2 1670(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1671most likely cause of this error is that you left out a parenthesis inside
1672of the C<....> part.
1673
9e3ec65c 1674The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1675discovered.
1676
62658f4d
PM
1677=item %s defines neither package nor VERSION--version check failed
1678
1679(F) You said something like "use Module 42" but in the Module file
1680there are neither package declarations nor a C<$VERSION>.
1681
36447869
FC
1682=item delete argument is index/value array slice, use array slice
1683
1684(F) You used index/value array slice syntax (C<%array[...]>) as
1685the argument to C<delete>. You probably meant C<@array[...]> with
1686an @ symbol instead.
1687
1688=item delete argument is key/value hash slice, use hash slice
1689
1690(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1691C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1692
0ffcbc25
FC
1693=item delete argument is not a HASH or ARRAY element or slice
1694
4a0af295 1695(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1696such as:
1697
1698 $foo{$bar}
1699 $ref->{"susie"}[12]
1700
1701or a hash or array slice, such as:
1702
1703 @foo[$bar, $baz, $xyzzy]
1704 @{$ref->[12]}{"susie", "queue"}
1705
fc36a67e
PP
1706=item Delimiter for here document is too long
1707
be771a83
GS
1708(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1709long for Perl to handle. You have to be seriously twisted to write code
1710that triggers this error.
fc36a67e 1711
6d3b25aa
RGS
1712=item Deprecated use of my() in false conditional
1713
fa816bf3
FC
1714(D deprecated) You used a declaration similar to C<my $x if 0>. There
1715has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1716not to be cleared at scope exit when its declaration includes a false
6903afa2 1717conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1718static variable. Since we intend to fix this bug, we don't want people
6903afa2 1719relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1720declaring the variable in a separate block outside the function, eg
36fb85f3 1721
6d3b25aa
RGS
1722 sub f { my $x if 0; return $x++ }
1723
1724becomes
1725
1726 { my $x; sub f { return $x++ } }
1727
ea9d9ebc 1728Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1729lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1730
1731 sub f { state $x; return $x++ }
1732
500ab966
RGS
1733=item DESTROY created new reference to dead object '%s'
1734
1735(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1736just being DESTROYed. Perl is confused, and prefers to abort rather
1737than to create a dangling reference.
500ab966 1738
3cdd684c
TP
1739=item Did not produce a valid header
1740
1741See Server error.
1742
6df41af2
GS
1743=item %s did not return a true value
1744
1745(F) A required (or used) file must return a true value to indicate that
1746it compiled correctly and ran its initialization code correctly. It's
1747traditional to end such a file with a "1;", though any true value would
1748do. See L<perlfunc/require>.
1749
cc507455 1750=item (Did you mean &%s instead?)
4633a7c4 1751
413ff9f6
FC
1752(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1753some such.
4633a7c4 1754
cc507455 1755=item (Did you mean "local" instead of "our"?)
33633739 1756
be771a83
GS
1757(W misc) Remember that "our" does not localize the declared global
1758variable. You have declared it again in the same lexical scope, which
1759seems superfluous.
33633739 1760
cc507455 1761=item (Did you mean $ or @ instead of %?)
a0d0e21e 1762
be771a83
GS
1763(W) You probably said %hash{$key} when you meant $hash{$key} or
1764@hash{@keys}. On the other hand, maybe you just meant %hash and got
1765carried away.
748a9306 1766
7e1af8bc 1767=item Died
5f05dabc
PP
1768
1769(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1770you called it with no args and C<$@> was empty.
5f05dabc 1771
3cdd684c
TP
1772=item Document contains no data
1773
1774See Server error.
1775
62658f4d
PM
1776=item %s does not define %s::VERSION--version check failed
1777
1778(F) You said something like "use Module 42" but the Module did not
943fc58e 1779define a C<$VERSION>.
62658f4d 1780
49704364
LW
1781=item '/' does not take a repeat count
1782
1783(F) You cannot put a repeat count of any kind right after the '/' code.
1784See L<perlfunc/pack>.
1785
95cb0d72
FC
1786=item Don't know how to get file name
1787
1788(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1789somehow called on another platform. This should not happen.
1790
4021c788 1791=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1792
1793(P) The internal handling of magical variables has been cursed.
1794
1795=item do_study: out of memory
1796
1797(P) This should have been caught by safemalloc() instead.
1798
6df41af2
GS
1799=item (Do you need to predeclare %s?)
1800
56da5a46
RGS
1801(S syntax) This is an educated guess made in conjunction with the message
1802"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1803name is being referenced that hasn't been declared yet. This may be
1804because of ordering problems in your file, or because of a missing
be771a83
GS
1805"sub", "package", "require", or "use" statement. If you're referencing
1806something that isn't defined yet, you don't actually have to define the
1807subroutine or package before the current location. You can use an empty
1808"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1809
ac206dc8
RGS
1810=item dump() better written as CORE::dump()
1811
1812(W misc) You used the obsolescent C<dump()> built-in function, without fully
1813qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1814
84d78eb7
YO
1815=item dump is not supported
1816
1817(F) Your machine doesn't support dump/undump.
1818
a0d0e21e
LW
1819=item Duplicate free() ignored
1820
be771a83
GS
1821(S malloc) An internal routine called free() on something that had
1822already been freed.
a0d0e21e 1823
1109a392
MHM
1824=item Duplicate modifier '%c' after '%c' in %s
1825
35f0cd76
FC
1826(W unpack) You have applied the same modifier more than once after a
1827type in a pack template. See L<perlfunc/pack>.
1109a392 1828
0953b66b
FC
1829=item each on reference is experimental
1830
0773cb3e
FC
1831(S experimental::autoderef) C<each> with a scalar argument is experimental
1832and may change or be removed in a future Perl version. If you want to
1833take the risk of using this feature, simply disable this warning:
0953b66b 1834
d401967c 1835 no warnings "experimental::autoderef";
0953b66b 1836
4633a7c4
LW
1837=item elseif should be elsif
1838
fa816bf3
FC
1839(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1840it's ugly. Your code will be interpreted as an attempt to call a method
1841named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1842unlikely to be what you want.
1843
e0e4a6e3 1844=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1845
af6f566e 1846(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1847described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1848a regular expression without specifying the property name.
ab13f0c7 1849
85ab1d1d 1850=item entering effective %s failed
5ff3f7a4 1851
85ab1d1d 1852(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1853effective uids or gids failed.
1854
c038024b
RGS
1855=item %ENV is aliased to %s
1856
1857(F) You're running under taint mode, and the C<%ENV> variable has been
1858aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1859program's environment. This is potentially insecure.
c038024b 1860
748a9306
LW
1861=item Error converting file specification %s
1862
5f05dabc 1863(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1864specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1865single form when it must operate on them directly. Either you've passed
1866an invalid file specification to Perl, or you've found a case the
1867conversion routines don't handle. Drat.
748a9306 1868
ad19ef22 1869=item Eval-group in insecure regular expression
e4d48cc9 1870
be771a83
GS
1871(F) Perl detected tainted data when trying to compile a regular
1872expression that contains the C<(?{ ... })> zero-width assertion, which
1873is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1874
ad19ef22 1875=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1876
be771a83
GS
1877(F) Perl tried to compile a regular expression containing the
1878C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1879pattern contains interpolated values. Since that is a security risk,
1880it is not allowed. If you insist, you may still do this by using the
1881C<re 'eval'> pragma or by explicitly building the pattern from an
1882interpolated string at run time and using that in an eval(). See
1883L<perlre/(?{ code })>.
e4d48cc9 1884
ad19ef22 1885=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1886
be771a83
GS
1887(F) A regular expression contained the C<(?{ ... })> zero-width
1888assertion, but that construct is only allowed when the C<use re 'eval'>
1889pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1890
e0e4a6e3
FC
1891=item EVAL without pos change exceeded limit in regex; marked by
1892S<<-- HERE> in m/%s/
1a147d38
YO
1893
1894(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1895any text. Restructure the pattern so that text is consumed.
1a147d38 1896
9e3ec65c 1897The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1898discovered.
1899
fc36a67e
PP
1900=item Excessively long <> operator
1901
1902(F) The contents of a <> operator may not exceed the maximum size of a
1903Perl identifier. If you're just trying to glob a long list of
1904filenames, try using the glob() operator, or put the filenames into a
1905variable and glob that.
1906
ed9aa3b7
SG
1907=item exec? I'm not *that* kind of operating system
1908
af8bb25a 1909(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1910OS. See L<perlport>.
ed9aa3b7 1911
fe13d51d 1912=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1913
1914(F) The final summary message when a Perl compilation fails.
1915
0ffcbc25
FC
1916=item exists argument is not a HASH or ARRAY element or a subroutine
1917
4a0af295 1918(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1919subroutine with an ampersand, such as:
1920
1921 $foo{$bar}
1922 $ref->{"susie"}[12]
1923 &do_something
1924
1925=item exists argument is not a subroutine name
1926
ccfc2567
FC
1927(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1928and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1929
a0d0e21e
LW
1930=item Exiting eval via %s
1931
be771a83
GS
1932(W exiting) You are exiting an eval by unconventional means, such as a
1933goto, or a loop control statement.
e476b1b5
GS
1934
1935=item Exiting format via %s
1936
9a2ff54b 1937(W exiting) You are exiting a format by unconventional means, such as a
be771a83 1938goto, or a loop control statement.
a0d0e21e 1939
0a753a76
PP
1940=item Exiting pseudo-block via %s
1941
be771a83
GS
1942(W exiting) You are exiting a rather special block construct (like a
1943sort block or subroutine) by unconventional means, such as a goto, or a
1944loop control statement. See L<perlfunc/sort>.
0a753a76 1945
a0d0e21e
LW
1946=item Exiting subroutine via %s
1947
be771a83
GS
1948(W exiting) You are exiting a subroutine by unconventional means, such
1949as a goto, or a loop control statement.
a0d0e21e
LW
1950
1951=item Exiting substitution via %s
1952
be771a83
GS
1953(W exiting) You are exiting a substitution by unconventional means, such
1954as a return, a goto, or a loop control statement.
a0d0e21e 1955
e0e4a6e3 1956=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 1957
675fa9ff 1958(F) You wrote something like
c608e803
KW
1959
1960 (?13
1961
1962to denote a capturing group of the form
1963L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
1964but omitted the C<")">.
1965
e0e4a6e3 1966=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 1967
8b6fbf55
FC
1968(F) The C<(?[...])> extended character class regular expression construct
1969only allows character classes (including character class escapes like
1970C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
1971containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
1972This allows a regular expression containing just C<(?[...])> to be
1973interpolated. If you see this error message, then you probably
1974have some other C<(?...)> construct inside your character class. See
1975L<perlrecharclass/Extended Bracketed Character Classes>.
1976
baabe3fb 1977=item Experimental aliasing via reference not enabled
1f8155a2 1978
baabe3fb 1979(F) To do aliasing via references, you must first enable the feature:
1f8155a2 1980
baabe3fb
FC
1981 no warnings "experimental::refaliasing";
1982 use feature "refaliasing";
1f8155a2
FC
1983 \$x = \$y;
1984
30d9c59b
Z
1985=item Experimental subroutine signatures not enabled
1986
1987(F) To use subroutine signatures, you must first enable them:
1988
caa35032 1989 no warnings "experimental::signatures";
30d9c59b
Z
1990 use feature "signatures";
1991 sub foo ($left, $right) { ... }
1992
6da34ecb
FC
1993=item Experimental "%s" subs not enabled
1994
1995(F) To use lexical subs, you must first enable them:
1996
1997 no warnings 'experimental::lexical_subs';
1998 use feature 'lexical_subs';
1999 my sub foo { ... }
2000
7b8d334a
GS
2001=item Explicit blessing to '' (assuming package main)
2002
be771a83
GS
2003(W misc) You are blessing a reference to a zero length string. This has
2004the effect of blessing the reference into the package main. This is
2005usually not what you want. Consider providing a default target package,
2006e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2007
6df41af2
GS
2008=item %s: Expression syntax
2009
be771a83
GS
2010(A) You've accidentally run your script through B<csh> instead of Perl.
2011Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2012
2013=item %s failed--call queue aborted
2014
3c10abe3
AG
2015(F) An untrapped exception was raised while executing a UNITCHECK,
2016CHECK, INIT, or END subroutine. Processing of the remainder of the
2017queue of such routines has been prematurely ended.
6df41af2 2018
e0e4a6e3 2019=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2020
98d31c73 2021(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2022character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2023in your false range is interpreted as a literal "-". In a C<(?[...])>
2024construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2025the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2026the problem was discovered. See L<perlre>.
73b437c8 2027
1b1ee2ef 2028=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2029
be771a83
GS
2030(P) An error peculiar to VMS. Something untoward happened in a VMS
2031system service or RTL routine; Perl's exit status should provide more
2032details. The filename in "at %s" and the line number in "line %d" tell
2033you which section of the Perl source code is distressed.
a0d0e21e
LW
2034
2035=item fcntl is not implemented
2036
2037(F) Your machine apparently doesn't implement fcntl(). What is this, a
2038PDP-11 or something?
2039
22846ab4
AB
2040=item FETCHSIZE returned a negative value
2041
2042(F) A tied array claimed to have a negative number of elements, which
2043is not possible.
2044
f337b084
TH
2045=item Field too wide in 'u' format in pack
2046
d8b5cc61 2047(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2048which can't encode values above 63. So there is no point in asking for
2049a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2050C<u63> as the format.
f337b084 2051
af8c498a 2052=item Filehandle %s opened only for input
a0d0e21e 2053
6c8d78fb
HS
2054(W io) You tried to write on a read-only filehandle. If you intended
2055it to be a read-write filehandle, you needed to open it with "+<" or
2056"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2057write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2058
af8c498a 2059=item Filehandle %s opened only for output
a0d0e21e 2060
6c8d78fb
HS
2061(W io) You tried to read from a filehandle opened only for writing, If
2062you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2063with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2064read from the file, use "<". See L<perlfunc/open>. Another possibility
2065is that you attempted to open filedescriptor 0 (also known as STDIN) for
2066output (maybe you closed STDIN earlier?).
97828cef
RGS
2067
2068=item Filehandle %s reopened as %s only for input
2069
2070(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2071as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2072previously.
2073
2074=item Filehandle STDIN reopened as %s only for output
2075
2076(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2077as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2078
2079=item Final $ should be \$ or $name
2080
2081(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2082a literal dollar sign, or was meant to introduce a variable name that
2083happens to be missing. So you have to put either the backslash or the
2084name.
a0d0e21e 2085
56e90b21
GS
2086=item flock() on closed filehandle %s
2087
be771a83 2088(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2089some time before now. Check your control flow. flock() operates on
be771a83
GS
2090filehandles. Are you attempting to call flock() on a dirhandle by the
2091same name?
56e90b21 2092
6df41af2
GS
2093=item Format not terminated
2094
2095(F) A format must be terminated by a line with a solitary dot. Perl got
2096to the end of your file without finding such a line.
2097
a0d0e21e
LW
2098=item Format %s redefined
2099
e476b1b5 2100(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2101
2102 {
271595cc 2103 no warnings 'redefine';
a0d0e21e
LW
2104 eval "format NAME =...";
2105 }
2106
a0d0e21e
LW
2107=item Found = in conditional, should be ==
2108
e476b1b5 2109(W syntax) You said
a0d0e21e
LW
2110
2111 if ($foo = 123)
2112
2113when you meant
2114
2115 if ($foo == 123)
2116
2117(or something like that).
2118
6df41af2
GS
2119=item %s found where operator expected
2120
56da5a46
RGS
2121(S syntax) The Perl lexer knows whether to expect a term or an operator.
2122If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2123operator, it gives you this warning. Usually it indicates that an
2124operator or delimiter was omitted, such as a semicolon.
6df41af2 2125
a0d0e21e
LW
2126=item gdbm store returned %d, errno %d, key "%s"
2127
2128(S) A warning from the GDBM_File extension that a store failed.
2129
2130=item gethostent not implemented
2131
2132(F) Your C library apparently doesn't implement gethostent(), probably
2133because if it did, it'd feel morally obligated to return every hostname
2134on the Internet.
2135
69282e91 2136=item get%sname() on closed socket %s
a0d0e21e 2137
be771a83
GS
2138(W closed) You tried to get a socket or peer socket name on a closed
2139socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2140
748a9306
LW
2141=item getpwnam returned invalid UIC %#o for user "%s"
2142
2143(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2144C<getpwnam> operator returned an invalid UIC.
2145
6df41af2
GS
2146=item getsockopt() on closed socket %s
2147
be771a83
GS
2148(W closed) You tried to get a socket option on a closed socket. Did you
2149forget to check the return value of your socket() call? See
6df41af2
GS
2150L<perlfunc/getsockopt>.
2151
0f539b13
BF
2152=item given is experimental
2153
675fa9ff
FC
2154(S experimental::smartmatch) C<given> depends on smartmatch, which
2155is experimental, so its behavior may change or even be removed
2156in any future release of perl. See the explanation under
2157L<perlsyn/Experimental Details on given and when>.
0f539b13 2158
68567d27
FC
2159=item Global symbol "%s" requires explicit package name (did you forget to
2160declare "my %s"?)
6df41af2 2161
a4edf47d 2162(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2163that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2164declared beforehand using "our", or explicitly qualified to say
2165which package the global variable is in (using "::").
6df41af2 2166
e476b1b5
GS
2167=item glob failed (%s)
2168
5ead438e 2169(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2170for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2171pattern that caused the external program to fail and exit with a
be771a83 2172nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2173resulted in a coredump, this may also mean that your csh (C shell)
2174is broken. If so, you should change all of the csh-related variables
2175in config.sh: If you have tcsh, make the variables refer to it as
2176if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2177all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2178think csh is missing. In either case, after editing config.sh, run
75b44862 2179C<./Configure -S> and rebuild Perl.
e476b1b5 2180
a0d0e21e
LW
2181=item Glob not terminated
2182
2183(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2184a term, so it's looking for the corresponding right angle bracket, and
2185not finding it. Chances are you left some needed parentheses out
2186earlier in the line, and you really meant a "less than".
a0d0e21e 2187
b35b96b6
JH
2188=item gmtime(%f) failed
2189
2190(W overflow) You called C<gmtime> with a number that it could not handle:
2191too large, too small, or NaN. The returned value is C<undef>.
2192
bcd05b94 2193=item gmtime(%f) too large
8b56d6ff 2194
e9200be3 2195(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2196it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2197date. This warning is also triggered with NaN (the special
fc003d4b
MS
2198not-a-number value).
2199
bcd05b94 2200=item gmtime(%f) too small
fc003d4b 2201
e9200be3 2202(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2203it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2204
6df41af2 2205=item Got an error from DosAllocMem
a0d0e21e 2206
6df41af2
GS
2207(P) An error peculiar to OS/2. Most probably you're using an obsolete
2208version of Perl, and this should not happen anyway.
a0d0e21e
LW
2209
2210=item goto must have label
2211
2212(F) Unlike with "next" or "last", you're not allowed to goto an
2213unspecified destination. See L<perlfunc/goto>.
2214
6651ba0b
FC
2215=item Goto undefined subroutine%s
2216
2217(F) You tried to call a subroutine with C<goto &sub> syntax, but
2218the indicated subroutine hasn't been defined, or if it was, it
2219has since been undefined.
2220
6fbc9859 2221=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2222S<<-- HERE> in m/%s/
1f4f6bf1
YO
2223
2224(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2225they must start with a non-digit word character. A common cause of
2226this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2227
5a25739d
FC
2228=item ()-group starts with a count
2229
2230(F) A ()-group started with a count. A count is supposed to follow
2231something: a template character or a ()-group. See L<perlfunc/pack>.
2232
fe13d51d 2233=item %s had compilation errors.
6df41af2
GS
2234
2235(F) The final summary message when a C<perl -c> fails.
2236
a0d0e21e
LW
2237=item Had to create %s unexpectedly
2238
be771a83
GS
2239(S internal) A routine asked for a symbol from a symbol table that ought
2240to have existed already, but for some reason it didn't, and had to be
2241created on an emergency basis to prevent a core dump.
a0d0e21e 2242
6df41af2
GS
2243=item %s has too many errors
2244
2245(F) The parser has given up trying to parse the program after 10 errors.
2246Further error messages would likely be uninformative.
2247
cc4d09e1
KW
2248=item Having more than one /%c regexp modifier is deprecated
2249
2250(D deprecated, regexp) You used the indicated regular expression pattern
2251modifier at least twice in a string of modifiers. It is deprecated to
2252do this with this particular modifier, to allow future extensions to the
2253Perl language.
2254
61e61fbc
JH
2255=item Hexadecimal float: exponent overflow
2256
d8f2b442 2257(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2258than the floating point supports.
2259
2260=item Hexadecimal float: exponent underflow
2261
d8f2b442 2262(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2263than the floating point supports.
2264
cf4f6003
JH
2265=item Hexadecimal float: internal error
2266
2267(F) Something went horribly bad in hexadecimal float handling.
2268
61e61fbc
JH
2269=item Hexadecimal float: mantissa overflow
2270
2271(W overflow) The hexadecimal floating point literal had more bits in
2272the mantissa (the part between the 0x and the exponent, also known as
2273the fraction or the significand) than the floating point supports.
2274
40bca5ae
JH
2275=item Hexadecimal float: precision loss
2276
2277(W overflow) The hexadecimal floating point had internally more
2278digits than could be output. This can be caused by unsupported
2279long double formats, or by 64-bit integers not being available
2280(needed to retrieve the digits under some configurations).
2281
2282=item Hexadecimal float: unsupported long double format
2283
2284(F) You have configured Perl to use long doubles but
d8f2b442 2285the internals of the long double format are unknown;
40bca5ae
JH
2286therefore the hexadecimal float output is impossible.
2287
252aa082
JH
2288=item Hexadecimal number > 0xffffffff non-portable
2289
e476b1b5 2290(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2291(4294967295) and therefore non-portable between systems. See
2292L<perlport> for more on portability concerns.
252aa082 2293
8903cb82
PP
2294=item Identifier too long
2295
2296(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2297about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2298names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2299of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2300
e0e4a6e3
FC
2301=item Ignoring zero length \N{} in character class in regex; marked by
2302S<<-- HERE> in m/%s/
fc8cd66c 2303
f3ba6905 2304(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
b5e3739b
FC
2305zero-length sequence. When such an escape is used in a character class
2306its behaviour is not well defined. Check that the correct escape has
fc8cd66c
YO
2307been used, and the correct charname handler is in scope.
2308
6df41af2 2309=item Illegal binary digit %s
f675dbe5 2310
6df41af2 2311(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2312
6df41af2 2313=item Illegal binary digit %s ignored
a0d0e21e 2314
be771a83
GS
2315(W digit) You may have tried to use a digit other than 0 or 1 in a
2316binary number. Interpretation of the binary number stopped before the
2317offending digit.
a0d0e21e 2318
6597eb22
FC
2319=item Illegal character after '_' in prototype for %s : %s
2320
e4d150f1
FC
2321(W illegalproto) An illegal character was found in a prototype
2322declaration. The '_' in a prototype must be followed by a ';',
2323indicating the rest of the parameters are optional, or one of '@'
2324or '%', since those two will accept 0 or more final parameters.
6597eb22 2325
78d0fecf 2326=item Illegal character \%o (carriage return)
4fdae800 2327
d5898338 2328(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2329would any other whitespace, which means you should never see this error
2330when Perl was built using standard options. For some reason, your
2331version of Perl appears to have been built without this support. Talk
2332to your Perl administrator.
4fdae800 2333
d37a9538
ST
2334=item Illegal character in prototype for %s : %s
2335
197afce1 2336(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2337Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2338Perhaps you were trying to write a subroutine signature but didn't enable
2339that feature first (C<use feature 'signatures'>), so your signature was
2340instead interpreted as a bad prototype.
d37a9538 2341
904d85c5
RGS
2342=item Illegal declaration of anonymous subroutine
2343
2344(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2345you must always specify a block of code. See L<perlsub>.
904d85c5 2346
8e742a20
MHM
2347=item Illegal declaration of subroutine %s
2348
6903afa2 2349(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2350
a0d0e21e
LW
2351=item Illegal division by zero
2352
be771a83
GS
2353(F) You tried to divide a number by 0. Either something was wrong in
2354your logic, or you need to put a conditional in to guard against
2355meaningless input.
a0d0e21e 2356
6df41af2
GS
2357=item Illegal hexadecimal digit %s ignored
2358
be771a83
GS
2359(W digit) You may have tried to use a character other than 0 - 9 or
2360A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2361number stopped before the illegal character.
6df41af2 2362
a0d0e21e
LW
2363=item Illegal modulus zero
2364
be771a83
GS
2365(F) You tried to divide a number by 0 to get the remainder. Most
2366numbers don't take to this kindly.
a0d0e21e 2367
6df41af2 2368=item Illegal number of bits in vec
399388f4 2369
6df41af2
GS
2370(F) The number of bits in vec() (the third argument) must be a power of
2371two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2372
2373=item Illegal octal digit %s
a0d0e21e 2374
d1be9408 2375(F) You used an 8 or 9 in an octal number.
a0d0e21e 2376
399388f4 2377=item Illegal octal digit %s ignored
748a9306 2378
d1be9408 2379(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2380Interpretation of the octal number stopped before the 8 or 9.
748a9306 2381
e0e4a6e3 2382=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2383
675fa9ff 2384(F) You wrote something like
c608e803
KW
2385
2386 (?+foo)
2387
2388The C<"+"> is valid only when followed by digits, indicating a
2389capturing group. See
2390L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2391
375ed12a
JH
2392=item Illegal suidscript
2393
2394(F) The script run under suidperl was somehow illegal.
2395
fe13d51d 2396=item Illegal switch in PERL5OPT: -%c
6ff81951 2397
6df41af2 2398(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2399following switches: B<-[CDIMUdmtw]>.
6ff81951 2400
6df41af2 2401=item Ill-formed CRTL environ value "%s"
81e118e0 2402
75b44862 2403(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2404internal environ array, and encountered an element without the C<=>
2405delimiter used to separate keys from values. The element is ignored.
09bef843 2406
6df41af2 2407=item Ill-formed message in prime_env_iter: |%s|
54310121 2408
be771a83
GS
2409(W internal) A warning peculiar to VMS. Perl tried to read a logical
2410name or CLI symbol definition when preparing to iterate over %ENV, and
2411didn't see the expected delimiter between key and value, so the line was
2412ignored.
54310121 2413
6df41af2 2414=item (in cleanup) %s
9607fc9c 2415
be771a83
GS
2416(W misc) This prefix usually indicates that a DESTROY() method raised
2417the indicated exception. Since destructors are usually called by the
2418system at arbitrary points during execution, and often a vast number of
2419times, the warning is issued only once for any number of failures that
2420would otherwise result in the same message being repeated.
6df41af2 2421
be771a83
GS
2422Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2423also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2424
e0e4a6e3
FC
2425=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2426in m/%s/
0d0b4b3b 2427
675fa9ff 2428(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2429expression inside the construct was completely empty, or if there are
2430too many or few operands for the number of operators. Perl is not smart
2431enough to give you a more precise indication as to what is wrong.
2432
6fbc9859
MH
2433=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2434parent '%s'
2c7d6b9c
RGS
2435
2436(F) The method resolution order (MRO) of the given class is not
2437C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2438documentation in L<mro> for more information.
2439
979699d9
JH
2440=item In EBCDIC the v-string components cannot exceed 2147483647
2441
2442(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2443Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2444encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2445
6a2ed79a 2446=item Infinite recursion in regex
1a147d38
YO
2447
2448(F) You used a pattern that references itself without consuming any input
6903afa2 2449text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2450either consume text or fail.
2451
6dbe9451
NC
2452=item Initialization of state variables in list context currently forbidden
2453
6903afa2
FC
2454(F) Currently the implementation of "state" only permits the
2455initialization of scalar variables in scalar context. Re-write
2456C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2457context. Constructions such as C<state (@a) = foo()> will be
2458supported in a future perl release.
6dbe9451 2459
2186f873
FC
2460=item %%s[%s] in scalar context better written as $%s[%s]
2461
2462(W syntax) In scalar context, you've used an array index/value slice
2463(indicated by %) to select a single element of an array. Generally
2464it's better to ask for a scalar value (indicated by $). The difference
2465is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2466returns and when evaluating its argument, while C<%foo[&bar]> provides
2467a list context to its subscript, which can do weird things if you're
2468expecting only one subscript. When called in list context, it also
2469returns the index (what C<&bar> returns) in addition to the value.
2470
2471=item %%s{%s} in scalar context better written as $%s{%s}
2472
2473(W syntax) In scalar context, you've used a hash key/value slice
2474(indicated by %) to select a single element of a hash. Generally it's
2475better to ask for a scalar value (indicated by $). The difference
2476is that C<$foo{&bar}> always behaves like a scalar, both in the value
2477it returns and when evaluating its argument, while C<@foo{&bar}> and
2478provides a list context to its subscript, which can do weird things
2479if you're expecting only one subscript. When called in list context,
2480it also returns the key in addition to the value.
2481
a0d0e21e
LW
2482=item Insecure dependency in %s
2483
8b1a09fc 2484(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2485The tainting mechanism is turned on when you're running setuid or
2486setgid, or when you specify B<-T> to turn it on explicitly. The
2487tainting mechanism labels all data that's derived directly or indirectly
2488from the user, who is considered to be unworthy of your trust. If any
2489such data is used in a "dangerous" operation, you get this error. See
2490L<perlsec> for more information.
a0d0e21e
LW
2491
2492=item Insecure directory in %s
2493
be771a83
GS
2494(F) You can't use system(), exec(), or a piped open in a setuid or
2495setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2496the world. Also, the PATH must not contain any relative directory.
2497See L<perlsec>.
a0d0e21e 2498
62f468fc 2499=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2500
2501(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2502setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2503C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2504supplied (or potentially supplied) by the user. The script must set
2505the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2506
0e9be77f
DM
2507=item Insecure user-defined property %s
2508
2509(F) Perl detected tainted data when trying to compile a regular
2510expression that contains a call to a user-defined character property
2511function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2512See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2513
b9ef414d
FC
2514=item Integer overflow in format string for %s
2515
2516(F) The indexes and widths specified in the format string of C<printf()>
2517or C<sprintf()> are too large. The numbers must not overflow the size of
2518integers for your architecture.
2519
a7ae9550
GS
2520=item Integer overflow in %s number
2521
35928bc5 2522(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2523either as a literal or as an argument to hex() or oct() is too big for
2524your architecture, and has been converted to a floating point number.
2525On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2526representable without overflow is 0xFFFFFFFF, 037777777777, or
25270b11111111111111111111111111111111 respectively. Note that Perl
2528transparently promotes all numbers to a floating point representation
2529internally--subject to loss of precision errors in subsequent
2530operations.
bbce6d69 2531
fc89ca81
FC
2532=item Integer overflow in srand
2533
2534(S overflow) The number you have passed to srand is too big to fit
2535in your architecture's integer representation. The number has been
2536replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2537architectures). This means you may be getting less randomness than
2538you expect, because different random seeds above the maximum will
2539return the same sequence of random numbers.
2540
46314c13
JP
2541=item Integer overflow in version
2542
18da5252
FC
2543=item Integer overflow in version %d
2544
784d71ed
FC
2545(W overflow) Some portion of a version initialization is too large for
2546the size of integers for your architecture. This is not a warning
f084e84f 2547because there is no rational reason for a version to try and use an
784d71ed
FC
2548element larger than typically 2**32. This is usually caused by trying
2549to use some odd mathematical operation as a version, like 100/9.
46314c13 2550
e0e4a6e3 2551=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2552
2553(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2554The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2555discovered.
2556
748a9306
LW
2557=item Internal inconsistency in tracking vforks
2558
be771a83
GS
2559(S) A warning peculiar to VMS. Perl keeps track of the number of times
2560you've called C<fork> and C<exec>, to determine whether the current call
2561to C<exec> should affect the current script or a subprocess (see
2562L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2563Perl is making a guess and treating this C<exec> as a request to
2564terminate the Perl script and execute the specified command.
748a9306 2565
870978ae
FC
2566=item internal %<num>p might conflict with future printf extensions
2567
2568(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2569formatting follows a slightly different set of rules when called from
2570C or XS code. Specifically, formats consisting of digits followed
2571by "p" (e.g., "%7p") are reserved for future use. If you see this
2572message, then an XS module tried to call that routine with one such
2573reserved format.
2574
e0e4a6e3 2575=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2576
fa816bf3 2577(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2578S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2579discovered.
a0d0e21e 2580
6df41af2
GS
2581=item %s (...) interpreted as function
2582
75b44862 2583(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2584followed by parentheses turns into a function, with all the list
64977eb6 2585operators arguments found inside the parentheses. See
13a2d996 2586L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2587
f51551f7
FC
2588=item In '(?...)', the '(' and '?' must be adjacent in regex;
2589marked by S<<-- HERE> in m/%s/
2590
2591(F) The two-character sequence C<"(?"> in this context in a regular
2592expression pattern should be an indivisible token, with nothing
2593intervening between the C<"("> and the C<"?">, but you separated them
2594with whitespace.
2595
09bef843
SB
2596=item Invalid %s attribute: %s
2597
a4a4c9e2 2598(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2599by Perl or by a user-supplied handler. See L<attributes>.
2600
2601=item Invalid %s attributes: %s
2602
a4a4c9e2 2603(F) The indicated attributes for a subroutine or variable were not
be771a83 2604recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2605
e0e4a6e3
FC
2606=item Invalid character in charnames alias definition; marked by
2607S<<-- HERE> in '%s
225fb84f
KW
2608
2609(F) You tried to create a custom alias for a character name, with
2610the C<:alias> option to C<use charnames> and the specified character in
2611the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2612
c8028aa6
TC
2613=item Invalid \0 character in %s for %s: %s\0%s
2614
fa3234e3
FC
2615(W syscalls) Embedded \0 characters in pathnames or other system call
2616arguments produce a warning as of 5.20. The parts after the \0 were
2617formerly ignored by system calls.
c8028aa6 2618
e0e4a6e3 2619=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2620
2621(F) Only certain characters are valid for character names. The
2622indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2623
c635e13b
PP
2624=item Invalid conversion in %s: "%s"
2625
be771a83
GS
2626(W printf) Perl does not understand the given format conversion. See
2627L<perlfunc/sprintf>.
c635e13b 2628
e0e4a6e3
FC
2629=item Invalid escape in the specified encoding in regex; marked by
2630S<<-- HERE> in m/%s/
9e08bc66 2631
98d31c73 2632(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2633didn't correspond to a single character through the conversion
2634from the encoding specified by the encoding pragma.
98d31c73
FC
2635The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2636instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2637The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2638escape was discovered.
2639
8149aa9f
FC
2640=item Invalid hexadecimal number in \N{U+...}
2641
e0e4a6e3
FC
2642=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2643S<<-- HERE> in m/%s/
aec0ef10 2644
8149aa9f 2645(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2646number. Either it is empty, or you tried to use a character other than
26470 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2648
6651ba0b
FC
2649=item Invalid module name %s with -%c option: contains single ':'
2650
2651(F) The module argument to perl's B<-m> and B<-M> command-line options
2652cannot contain single colons in the module name, but only in the
2653arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2654B<-MFoo:Bar=baz> is not.
2655
2c7d6b9c
RGS
2656=item Invalid mro name: '%s'
2657
162a3e34
FC
2658(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2659where C<foo> is not a valid method resolution order (MRO). Currently,
2660the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2661a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2662
40e4140b
FC
2663=item Invalid negative number (%s) in chr
2664
2665(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2666not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2667character (U+FFFD).
2668
6651ba0b
FC
2669=item invalid option -D%c, use -D'' to see choices
2670
8ff21bfe
FC
2671(S debugging) Perl was called with invalid debugger flags. Call perl
2672with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2673See also L<perlrun/-Dletters>.
6651ba0b 2674
e0e4a6e3 2675=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2676
2677(F) The range specified in a character class had a minimum character
7253e4e3
RK
2678greater than the maximum character. One possibility is that you forgot the
2679C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2680up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2681problem was discovered. See L<perlre>.
6df41af2 2682
d1573ac7 2683=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2684
2685(F) The range specified in the tr/// or y/// operator had a minimum
2686character greater than the maximum character. See L<perlop>.
2687
09bef843
SB
2688=item Invalid separator character %s in attribute list
2689
0120eecf 2690(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2691elements of an attribute list. If the previous attribute had a
2692parenthesised parameter list, perhaps that list was terminated too soon.
2693See L<attributes>.
09bef843 2694
b4581f09
JH
2695=item Invalid separator character %s in PerlIO layer specification %s
2696
2bfc5f71
FC
2697(W layer) When pushing layers onto the Perl I/O system, something other
2698than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2699If the previous attribute had a parenthesised parameter list, perhaps that
2700list was terminated too soon.
2701
2c86d456
DG
2702=item Invalid strict version format (%s)
2703
fa816bf3 2704(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2705A "strict" version number is a positive decimal number (integer or
2706decimal-fraction) without exponentiation or else a dotted-decimal
2707v-string with a leading 'v' character and at least three components.
a6485a24 2708The parenthesized text indicates which criteria were not met.
2c86d456
DG
2709See the L<version> module for more details on allowed version formats.
2710
49704364 2711=item Invalid type '%s' in %s
96e4d5b1 2712
49704364
LW
2713(F) The given character is not a valid pack or unpack type.
2714See L<perlfunc/pack>.
6728c851 2715
49704364 2716(W) The given character is not a valid pack or unpack type but used to be
75b44862 2717silently ignored.
96e4d5b1 2718
2c86d456
DG
2719=item Invalid version format (%s)
2720
fa816bf3 2721(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2722A "lax" version number is a positive decimal number (integer or
2723decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2724v-string. If the v-string has fewer than three components, it
2725must have a leading 'v' character. Otherwise, the leading 'v' is
2726optional. Both decimal and dotted-decimal versions may have a
2727trailing "alpha" component separated by an underscore character
2728after a fractional or dotted-decimal component. The parenthesized
2729text indicates which criteria were not met. See the L<version> module
2730for more details on allowed version formats.
46314c13 2731
798ae1b7
DG
2732=item Invalid version object
2733
fa816bf3
FC
2734(F) The internal structure of the version object was invalid.
2735Perhaps the internals were modified directly in some way or
2736an arbitrary reference was blessed into the "version" class.
798ae1b7 2737
cd209d9d 2738=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2739marked by S<<-- HERE> in m/%s/
675fa9ff 2740
cd209d9d 2741(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2742this context in a regular expression pattern should be an
2743indivisible token, with nothing intervening between the C<"(">
cd209d9d 2744and the C<"*">, but you separated them.
675fa9ff 2745
a0d0e21e
LW
2746=item ioctl is not implemented
2747
2748(F) Your machine apparently doesn't implement ioctl(), which is pretty
2749strange for a machine that supports C.
2750
c289d2f7
JH
2751=item ioctl() on unopened %s
2752
2753(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2754Check your control flow and number of arguments.
c289d2f7 2755
fe13d51d 2756=item IO layers (like '%s') unavailable
363c40c4
SB
2757
2758(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2759you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2760with 'useperlio'.
2761
80cbd5ad
JH
2762=item IO::Socket::atmark not implemented on this architecture
2763
2764(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2765neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2766
4f650b80 2767=item $* is no longer supported
b4581f09 2768
4f650b80 2769(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2770perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2771previous versions of perl the use of C<$*> enabled or disabled multi-line
2772matching within a string.
4fd19576
B
2773
2774Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2775modifiers. You can enable C</m> for a lexical scope (even a whole file)
2776with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2777then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2778
8ae1fe26
RGS
2779=item $# is no longer supported
2780
a58ac25e 2781(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2782perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2783should use the printf/sprintf functions instead.
8ae1fe26 2784
ccf3535a 2785=item '%s' is not a code reference
6ad11d81 2786
6903afa2
FC
2787(W overload) The second (fourth, sixth, ...) argument of
2788overload::constant needs to be a code reference. Either
2789an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2790
ccf3535a 2791=item '%s' is not an overloadable type
6ad11d81 2792
04a80ee0
RGS
2793(W overload) You tried to overload a constant type the overload package is
2794unaware of.
6ad11d81 2795
5a25739d
FC
2796=item -i used with no filenames on the command line, reading from STDIN
2797
2798(S inplace) The C<-i> option was passed on the command line, indicating
2799that the script is intended to edit files in place, but no files were
2800given. This is usually a mistake, since editing STDIN in place doesn't
2801make sense, and can be confusing because it can make perl look like
2802it is hanging when it is really just trying to read from STDIN. You
2803should either pass a filename to edit, or remove C<-i> from the command
2804line. See L<perlrun> for more details.
2805
aec0ef10 2806=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2807
2808(P) The regular expression parser is confused.
2809
0953b66b
FC
2810=item keys on reference is experimental
2811
0773cb3e
FC
2812(S experimental::autoderef) C<keys> with a scalar argument is experimental
2813and may change or be removed in a future Perl version. If you want to
2814take the risk of using this feature, simply disable this warning:
0953b66b 2815
d401967c 2816 no warnings "experimental::autoderef";
0953b66b 2817
a0d0e21e
LW
2818=item Label not found for "last %s"
2819
be771a83
GS
2820(F) You named a loop to break out of, but you're not currently in a loop
2821of that name, not even if you count where you were called from. See
2822L<perlfunc/last>.
a0d0e21e
LW
2823
2824=item Label not found for "next %s"
2825
2826(F) You named a loop to continue, but you're not currently in a loop of
2827that name, not even if you count where you were called from. See
2828L<perlfunc/last>.
2829
2830=item Label not found for "redo %s"
2831
2832(F) You named a loop to restart, but you're not currently in a loop of
2833that name, not even if you count where you were called from. See
2834L<perlfunc/last>.
2835
85ab1d1d 2836=item leaving effective %s failed
5ff3f7a4 2837
85ab1d1d 2838(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2839effective uids or gids failed.
2840
49704364
LW
2841=item length/code after end of string in unpack
2842
d7f8936a 2843(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2844length/code combination tried to obtain more data. This results in
2845an undefined value for the length. See L<perlfunc/pack>.
49704364 2846
25e26107 2847=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2848
0d46a4e7
FC
2849(W syntax) You used length() on either an array or a hash when you
2850probably wanted a count of the items.
e508c8a4
MH
2851
2852Array size can be obtained by doing:
2853
2854 scalar(@array);
2855
2856The number of items in a hash can be obtained by doing:
2857
2858 scalar(keys %hash);
2859
f0e67a1d
Z
2860=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2861
d4fe7078
RS
2862(F) An extension is attempting to insert text into the current parse
2863(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2864couldn't be part of the current input. This is an inherent pitfall
2865of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2866it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2867
2868=item Lexing code internal error (%s)
2869
2870(F) Lexing code supplied by an extension violated the lexer's API in a
2871detectable way.
2872
69282e91 2873=item listen() on closed socket %s
a0d0e21e 2874
be771a83
GS
2875(W closed) You tried to do a listen on a closed socket. Did you forget
2876to check the return value of your socket() call? See
2877L<perlfunc/listen>.
a0d0e21e 2878
6651ba0b
FC
2879=item List form of piped open not implemented
2880
2881(F) On some platforms, notably Windows, the three-or-more-arguments
2882form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2883Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2884
b35b96b6
JH
2885=item localtime(%f) failed
2886
2887(W overflow) You called C<localtime> with a number that it could not handle:
2888too large, too small, or NaN. The returned value is C<undef>.
2889
bcd05b94 2890=item localtime(%f) too large
8b56d6ff 2891
e9200be3 2892(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2893than it can reliably handle and C<localtime> probably returned the
6903afa2 2894wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2895not-a-number value).
2896
bcd05b94 2897=item localtime(%f) too small
fc003d4b 2898
e9200be3 2899(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2900than it can reliably handle and C<localtime> probably returned the
e7a1a147 2901wrong date.
8b56d6ff 2902
58e23c8d 2903=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2904
2905(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2906handle. This restriction may be eased in a future release.
2e50fd82 2907
b88df990
NC
2908=item Lost precision when %s %f by 1
2909
e63e8a91
FC
2910(W imprecision) The value you attempted to increment or decrement by one
2911is too large for the underlying floating point representation to store
2912accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2913warning because it has already switched from integers to floating point
2914when values are too large for integers, and now even floating point is
2915insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2916
93fad930 2917=item lstat() on filehandle%s
2f7da168
RK
2918
2919(W io) You tried to do an lstat on a filehandle. What did you mean
2920by that? lstat() makes sense only on filenames. (Perl did a fstat()
2921instead on the filehandle.)
2922
345d70e3 2923=item lvalue attribute %s already-defined subroutine
bb3abb05 2924
345d70e3
FC
2925(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2926attribute on or off on a Perl subroutine that is already defined
2927does not always work properly. It may or may not do what you
2928want, depending on what code is inside the subroutine, with exact
2929details subject to change between Perl versions. Only do this
2930if you really know what you are doing.
bb3abb05 2931
885ef6f5
GG
2932=item lvalue attribute ignored after the subroutine has been defined
2933
345d70e3
FC
2934(W misc) Using the C<:lvalue> declarative syntax to make a Perl
2935subroutine an lvalue subroutine after it has been defined is
2936not permitted. To make the subroutine an lvalue subroutine,
2937add the lvalue attribute to the definition, or put the C<sub
2938foo :lvalue;> declaration before the definition.
2939
2940See also L<attributes.pm|attributes>.
885ef6f5 2941
6f1b3ab0
FC
2942=item Magical list constants are not supported
2943
2944(F) You assigned a magical array to a stash element, and then tried
2945to use the subroutine from the same slot. You are asking Perl to do
2946something it cannot do, details subject to change between Perl versions.
2947
2db62bbc 2948=item Malformed integer in [] in pack
49704364 2949
2db62bbc 2950(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2951are permitted. See L<perlfunc/pack>.
2952
2953=item Malformed integer in [] in unpack
2954
2db62bbc 2955(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
2956are permitted. See L<perlfunc/pack>.
2957
6df41af2
GS
2958=item Malformed PERLLIB_PREFIX
2959
2960(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
2961
2962 prefix1;prefix2
2963
2964or
6df41af2
GS
2965 prefix1 prefix2
2966
be771a83
GS
2967with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
2968a builtin library search path, prefix2 is substituted. The error may
2969appear if components are not found, or are too long. See
fecfaeb8 2970"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 2971
2f758a16
ST
2972=item Malformed prototype for %s: %s
2973
d37a9538
ST
2974(F) You tried to use a function with a malformed prototype. The
2975syntax of function prototypes is given a brief compile-time check for
2976obvious errors like invalid characters. A more rigorous check is run
2977when the function is called.
30d9c59b
Z
2978Perhaps the function's author was trying to write a subroutine signature
2979but didn't enable that feature first (C<use feature 'signatures'>),
2980so the signature was instead interpreted as a bad prototype.
2f758a16 2981
ba210ebe
JH
2982=item Malformed UTF-8 character (%s)
2983
4d6f11e5 2984(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 2985encoding rules, even though it had the UTF8 flag on.
ba210ebe 2986
2575c402
JW
2987One possible cause is that you set the UTF8 flag yourself for data that
2988you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 29898-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
2990
2991If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
2992sequences are handled gracefully, but if you use C<:utf8>, the flag is
2993set without validating the data, possibly resulting in this error
2994message.
2995
2996See also L<Encode/"Handling Malformed Data">.
901b21bf 2997
107160e2
KW
2998=item Malformed UTF-8 character immediately after '%s'
2999
3000(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3001encoding rules. The message prints out the properly encoded characters
3002just before the first bad one. If C<utf8> warnings are enabled, a
3003warning is generated that gives more details about the type of
3004malformation.
3005
bde9e88d 3006=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3007
3008(F) The charnames handler returned malformed UTF-8.
3009
4a5d3a93
FC
3010=item Malformed UTF-8 string in '%c' format in unpack
3011
3012(F) You tried to unpack something that didn't comply with UTF-8 encoding
3013rules and perl was unable to guess how to make more progress.
3014
f337b084
TH
3015=item Malformed UTF-8 string in pack
3016
3017(F) You tried to pack something that didn't comply with UTF-8 encoding
3018rules and perl was unable to guess how to make more progress.
3019
3020=item Malformed UTF-8 string in unpack
3021
3022(F) You tried to unpack something that didn't comply with UTF-8 encoding
3023rules and perl was unable to guess how to make more progress.
3024
4a5d3a93 3025=item Malformed UTF-16 surrogate
f337b084 3026
4a5d3a93
FC
3027(F) Perl thought it was reading UTF-16 encoded character data but while
3028doing it Perl met a malformed Unicode surrogate.
3029
30d9c59b
Z
3030=item Mandatory parameter follows optional parameter
3031
3032(F) In a subroutine signature, you wrote something like "$a = undef,
3033$b", making an earlier parameter optional and a later one mandatory.
3034Parameters are filled from left to right, so it's impossible for the
3035caller to omit an earlier one and pass a later one. If you want to act
3036as if the parameters are filled from right to left, declare the rightmost
3037optional and then shuffle the parameters around in the subroutine's body.
3038
2d88a86a
KW
3039=item Matched non-Unicode code point 0x%X against Unicode property; may
3040not be portable
3041
3042(S non_unicode) Perl allows strings to contain a superset of
3043Unicode code points; each code point may be as large as what is storable
3044in an unsigned integer on your system, but these may not be accepted by
3045other languages/systems. This message occurs when you matched a string
3046containing such a code point against a regular expression pattern, and
3047the code point was matched against a Unicode property, C<\p{...}> or
3048C<\P{...}>. Unicode properties are only defined on Unicode code points,
3049so the result of this match is undefined by Unicode, but Perl (starting
3050in v5.20) treats non-Unicode code points as if they were typical
3051unassigned Unicode ones, and matched this one accordingly. Whether a
3052given property matches these code points or not is specified in
3053L<perluniprops/Properties accessible through \p{} and \P{}>.
3054
3055This message is suppressed (unless it has been made fatal) if it is
3056immaterial to the results of the match if the code point is Unicode or
3057not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3058the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3059Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3060every code point except these 22.)
3061
3062Getting this message indicates that the outcome of the match arguably
3063should have been the opposite of what actually happened. If you think
3064that is the case, you may wish to make the C<non_unicode> warnings
3065category fatal; if you agree with Perl's decision, you may wish to turn
3066off this category.
3067
3068See L<perlunicode/Beyond Unicode code points> for more information.
3069
e0e4a6e3
FC
3070=item %s matches null string many times in regex; marked by S<<-- HERE> in
3071m/%s/
4a5d3a93
FC
3072
3073(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3074regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3075shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3076See L<perlre>.
f337b084 3077
de42a5a9 3078=item Maximal count of pending signals (%u) exceeded
2563cec5 3079
6903afa2 3080(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3081usually indicates that your operating system tried to deliver signals
3082too fast (with a very high priority), starving the perl process from
3083resources it would need to reach a point where it can process signals
6903afa2 3084safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3085
25f58aea
PN
3086=item "%s" may clash with future reserved word
3087
3088(W) This warning may be due to running a perl5 script through a perl4
3089interpreter, especially if the word that is being warned about is
3090"use" or "my".
3091
0d2487cd 3092=item '%' may not be used in pack
6df41af2
GS
3093
3094(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3095checksumming process loses information, and you can't go the other way.
3096See L<perlfunc/unpack>.
6df41af2 3097
a0d0e21e
LW
3098=item Method for operation %s not found in package %s during blessing
3099
3100(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3101doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3102
3cdd684c
TP
3103=item Method %s not permitted
3104
3105See Server error.
3106
a0d0e21e
LW
3107=item Might be a runaway multi-line %s string starting on line %d
3108
3109(S) An advisory indicating that the previous error may have been caused
3110by a missing delimiter on a string or pattern, because it eventually
3111ended earlier on the current line.
3112
3113=item Misplaced _ in number
3114
d4ced10d
JH
3115(W syntax) An underscore (underbar) in a numeric constant did not
3116separate two digits.
a0d0e21e 3117
7baa4690
HS
3118=item Missing argument in %s
3119
3664866e
AB
3120(W missing) You called a function with fewer arguments than other
3121arguments you supplied indicated would be needed.
3122
3123Currently only emitted when a printf-type format required more
3124arguments than were supplied, but might be used in the future for
3125other cases where we can statically determine that arguments to
3126functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3127
9e81e6a1
RGS
3128=item Missing argument to -%c
3129
3130(F) The argument to the indicated command line switch must follow
3131immediately after the switch, without intervening spaces.
3132
ff3f963a 3133=item Missing braces on \N{}
423cee85 3134
e0e4a6e3 3135=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3136
4a2d328f 3137(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3138double-quotish context. This can also happen when there is a space
3139(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3140This modifier does not change the requirement that the brace immediately
3141follow the C<\N>.
423cee85 3142
f0a2b745
KW
3143=item Missing braces on \o{}
3144
3145(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3146
a0d0e21e
LW
3147=item Missing comma after first argument to %s function
3148
3149(F) While certain functions allow you to specify a filehandle or an
3150"indirect object" before the argument list, this ain't one of them.
3151
06eaf0bc
GS
3152=item Missing command in piped open
3153
be771a83
GS
3154(W pipe) You used the C<open(FH, "| command")> or
3155C<open(FH, "command |")> construction, but the command was missing or
3156blank.
06eaf0bc 3157
961ce445
RGS
3158=item Missing control char name in \c
3159
3160(F) A double-quoted string ended with "\c", without the required control
3161character name.
3162
591f5ca2
FC
3163=item Missing ']' in prototype for %s : %s
3164
bfe11873 3165(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3166
8767b1ab 3167=item Missing name in "%s sub"
6df41af2 3168
87444db5 3169(F) The syntax for lexically scoped subroutines requires that
be771a83 3170they have a name with which they can be found.
6df41af2
GS
3171
3172=item Missing $ on loop variable
3173
be771a83
GS
3174(F) Apparently you've been programming in B<csh> too much. Variables
3175are always mentioned with the $ in Perl, unlike in the shells, where it
3176can vary from one line to the next.
6df41af2 3177
cc507455 3178=item (Missing operator before %s?)
748a9306 3179
56da5a46
RGS
3180(S syntax) This is an educated guess made in conjunction with the message
3181"%s found where operator expected". Often the missing operator is a comma.
748a9306 3182
f51551f7
FC
3183=item Missing or undefined argument to require
3184
3185(F) You tried to call require with no argument or with an undefined
3186value as an argument. Require expects either a package name or a
3187file-specification as an argument. See L<perlfunc/require>.
3188
e0e4a6e3 3189=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3190
ff3f963a
KW
3191(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3192
4a68bf9d 3193=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3194
d32207c9
FC
3195(F) C<\N> has two meanings.
3196
3197The traditional one has it followed by a name enclosed in braces,
3198meaning the character (or sequence of characters) given by that
fa816bf3 3199name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3200double-quoted strings and regular expression patterns. In patterns,
3201it doesn't have the meaning an unescaped C<*> does.
3202
3203Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3204in patterns, namely to match a non-newline character. (This is short
3205for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3206
3207This can lead to some ambiguities. When C<\N> is not followed immediately
3208by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3209form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3210means to match the given quantity of non-newlines (in these examples,
32113; and 5 or more, respectively). In all other case, where there is a
3212C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3213
3214However, if there is no matching C<}>, Perl doesn't know if it was
3215mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3216If you meant the former, add the right brace; if you meant the latter,
3217escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3218
d98d5fff 3219=item Missing right curly or square bracket
a0d0e21e 3220
be771a83
GS
3221(F) The lexer counted more opening curly or square brackets than closing
3222ones. As a general rule, you'll find it's missing near the place you
3223were last editing.
a0d0e21e 3224
6df41af2
GS
3225=item (Missing semicolon on previous line?)
3226
56da5a46
RGS
3227(S syntax) This is an educated guess made in conjunction with the message
3228"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3229the previous line just because you saw this message.
3230
a0d0e21e
LW
3231=item Modification of a read-only value attempted
3232
3233(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3234constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3235catches that. But an easy way to do the same thing is:
3236
3237 sub mod { $_[0] = 1 }
3238 mod(2);
3239
3240Another way is to assign to a substr() that's off the end of the string.
3241
c5674021
PDF
3242Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3243is aliased to a constant in the look I<LIST>:
3244
b7e4ecc1
FC
3245 $x = 1;
3246 foreach my $n ($x, 2) {
3247 $n *= 2; # modifies the $x, but fails on attempt to
3248 } # modify the 2
c5674021 3249
7a4340ed 3250=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3251
3252(F) You tried to make an array value spring into existence, and the
3253subscript was probably negative, even counting from end of the array
3254backwards.
3255
7a4340ed 3256=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3257
be771a83
GS
3258(P) You tried to make a hash value spring into existence, and it
3259couldn't be created for some peculiar reason.
a0d0e21e
LW
3260
3261=item Module name must be constant
3262
3263(F) Only a bare module name is allowed as the first argument to a "use".
3264
be98fb35 3265=item Module name required with -%c option
6df41af2 3266
be98fb35
GS
3267(F) The C<-M> or C<-m> options say that Perl should load some module, but
3268you omitted the name of the module. Consult L<perlrun> for full details
3269about C<-M> and C<-m>.
6df41af2 3270
fe13d51d 3271=item More than one argument to '%s' open
ed9aa3b7 3272
6903afa2 3273(F) The C<open> function has been asked to open multiple files. This
ed9aa3b7
SG
3274can happen if you are trying to open a pipe to a command that takes a
3275list of arguments, but have forgotten to specify a piped open mode.
3276See L<perlfunc/open> for details.
3277
85396b18
FC
3278=item mprotect for COW string %p %u failed with %d
3279
3280(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3281L<perlguts/"Copy on Write">), but a shared string buffer
3282could not be made read-only.
3283
92951bce
FC
3284=item mprotect for %p %u failed with %d
3285
85396b18
FC
3286(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see L<perlhacktips>),
3287but an op tree could not be made read-only.
3288
3289=item mprotect RW for COW string %p %u failed with %d
3290
3291(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_COW (see
3292L<perlguts/"Copy on Write">), but a read-only shared string
3293buffer could not be made mutable.
3294
92951bce
FC
3295=item mprotect RW for %p %u failed with %d
3296
3297(S) You compiled perl with B<-D>PERL_DEBUG_READONLY_OPS (see
85396b18
FC
3298L<perlhacktips>), but a read-only op tree could not be made
3299mutable before freeing the ops.
92951bce 3300
a0d0e21e
LW
3301=item msg%s not implemented
3302
3303(F) You don't have System V message IPC on your system.
3304
3305=item Multidimensional syntax %s not supported
3306
75b44862
GS
3307(W syntax) Multidimensional arrays aren't written like C<$foo[1,2,3]>.
3308They're written like C<$foo[1][2][3]>, as in C.
8b1a09fc 3309
49704364 3310=item '/' must follow a numeric type in unpack
6df41af2 3311
49704364
LW
3312(F) You had an unpack template that contained a '/', but this did not
3313follow some unpack specification producing a numeric value.
3314See L<perlfunc/pack>.
6df41af2
GS
3315
3316=item "my sub" not yet implemented
3317
be771a83
GS
3318(F) Lexically scoped subroutines are not yet implemented. Don't try
3319that yet.
6df41af2 3320