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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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FC
245=item <> at require-statement should be quotes
246
247(F) You wrote C<< require <file> >> when you should have written
248C<require 'file'>.
249
2393f1b9 250=item Attempt to access disallowed key '%s' in a restricted hash
1b1f1335 251
49293501 252(F) The failing code has attempted to get or set a key which is not in
2393f1b9 253the current set of allowed keys of a restricted hash.
49293501 254
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255=item Attempt to bless into a freed package
256
257(F) You wrote C<bless $foo> with one argument after somehow causing
258the current package to be freed. Perl cannot figure out what to
259do, so it throws up in hands in despair.
260
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261=item Attempt to bless into a reference
262
263(F) The CLASSNAME argument to the bless() operator is expected to be
57dedab9 264the name of the package to bless the resulting object into. You've
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265supplied instead a reference to something: perhaps you wrote
266
267 bless $self, $proto;
268
269when you intended
270
271 bless $self, ref($proto) || $proto;
272
273If you actually want to bless into the stringified version
274of the reference supplied, you need to stringify it yourself, for
275example by:
276
277 bless $self, "$proto";
278
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279=item Attempt to clear deleted array
280
281(S debugging) An array was assigned to when it was being freed.
282Freed values are not supposed to be visible to Perl code. This
283can also happen if XS code calls C<av_clear> from a custom magic
284callback on the array.
285
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286=item Attempt to delete disallowed key '%s' from a restricted hash
287
288(F) The failing code attempted to delete from a restricted hash a key
289which is not in its key set.
290
291=item Attempt to delete readonly key '%s' from a restricted hash
292
293(F) The failing code attempted to delete a key whose value has been
294declared readonly from a restricted hash.
295
de42a5a9 296=item Attempt to free non-arena SV: 0x%x
a0d0e21e 297
f84fe999 298(S internal) All SV objects are supposed to be allocated from arenas
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299that will be garbage collected on exit. An SV was discovered to be
300outside any of those arenas.
a0d0e21e 301
12578ffb 302=item Attempt to free nonexistent shared string '%s'%s
bbce6d69 303
f84fe999 304(S internal) Perl maintains a reference-counted internal table of
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305strings to optimize the storage and access of hash keys and other
306strings. This indicates someone tried to decrement the reference count
307of a string that can no longer be found in the table.
bbce6d69 308
7d5b40b4 309=item Attempt to free temp prematurely: SV 0x%x
a0d0e21e 310
f84fe999 311(S debugging) Mortalized values are supposed to be freed by the
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312free_tmps() routine. This indicates that something else is freeing the
313SV before the free_tmps() routine gets a chance, which means that the
314free_tmps() routine will be freeing an unreferenced scalar when it does
315try to free it.
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316
317=item Attempt to free unreferenced glob pointers
318
f84fe999 319(S internal) The reference counts got screwed up on symbol aliases.
a0d0e21e 320
7d5b40b4 321=item Attempt to free unreferenced scalar: SV 0x%x
a0d0e21e 322
8f7e4d2c 323(S internal) Perl went to decrement the reference count of a scalar to
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324see if it would go to 0, and discovered that it had already gone to 0
325earlier, and should have been freed, and in fact, probably was freed.
326This could indicate that SvREFCNT_dec() was called too many times, or
327that SvREFCNT_inc() was called too few times, or that the SV was
328mortalized when it shouldn't have been, or that memory has been
329corrupted.
a0d0e21e 330
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331=item Attempt to pack pointer to temporary value
332
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333(W pack) You tried to pass a temporary value (like the result of a
334function, or a computed expression) to the "p" pack() template. This
335means the result contains a pointer to a location that could become
336invalid anytime, even before the end of the current statement. Use
337literals or global values as arguments to the "p" pack() template to
338avoid this warning.
84902520 339
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340=item Attempt to reload %s aborted.
341
342(F) You tried to load a file with C<use> or C<require> that failed to
343compile once already. Perl will not try to compile this file again
344unless you delete its entry from %INC. See L<perlfunc/require> and
345L<perlvar/%INC>.
346
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347=item Attempt to set length of freed array
348
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349(W misc) You tried to set the length of an array which has
350been freed. You can do this by storing a reference to the
351scalar representing the last index of an array and later
352assigning through that reference. For example
1b20cd17
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353
354 $r = do {my @a; \$#a};
355 $$r = 503
356
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357=item Attempt to use reference as lvalue in substr
358
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359(W substr) You supplied a reference as the first argument to substr()
360used as an lvalue, which is pretty strange. Perhaps you forgot to
361dereference it first. See L<perlfunc/substr>.
b7a902f4 362
c32124fe
NC
363=item Attribute "locked" is deprecated
364
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365(D deprecated) You have used the attributes pragma to modify the
366"locked" attribute on a code reference. The :locked attribute is
367obsolete, has had no effect since 5005 threads were removed, and
368will be removed in a future release of Perl 5.
c32124fe 369
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370=item Attribute prototype(%s) discards earlier prototype attribute in same sub
371
372(W misc) A sub was declared as sub foo : prototype(A) : prototype(B) {}, for
373example. Since each sub can only have one prototype, the earlier
374declaration(s) are discarded while the last one is applied.
375
f1a3ce43
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376=item Attribute "unique" is deprecated
377
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378(D deprecated) You have used the attributes pragma to modify
379the "unique" attribute on an array, hash or scalar reference.
380The :unique attribute has had no effect since Perl 5.8.8, and
381will be removed in a future release of Perl 5.
f1a3ce43 382
ccce04a4
FC
383=item av_reify called on tied array
384
385(S debugging) This indicates that something went wrong and Perl got I<very>
386confused about C<@_> or C<@DB::args> being tied.
387
de42a5a9 388=item Bad arg length for %s, is %u, should be %d
a0d0e21e 389
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390(F) You passed a buffer of the wrong size to one of msgctl(), semctl()
391or shmctl(). In C parlance, the correct sizes are, respectively,
5f05dabc 392S<sizeof(struct msqid_ds *)>, S<sizeof(struct semid_ds *)>, and
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393S<sizeof(struct shmid_ds *)>.
394
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395=item Bad evalled substitution pattern
396
496a33f5 397(F) You've used the C</e> switch to evaluate the replacement for a
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398substitution, but perl found a syntax error in the code to evaluate,
399most likely an unexpected right brace '}'.
400
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401=item Bad filehandle: %s
402
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403(F) A symbol was passed to something wanting a filehandle, but the
404symbol has no filehandle associated with it. Perhaps you didn't do an
405open(), or did it in another package.
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406
407=item Bad free() ignored
408
be771a83 409(S malloc) An internal routine called free() on something that had never
fa816bf3 410been malloc()ed in the first place. Mandatory, but can be disabled by
9ea8bc6d 411setting environment variable C<PERL_BADFREE> to 0.
33c8a3fe 412
9ea8bc6d 413This message can be seen quite often with DB_File on systems with "hard"
6903afa2 414dynamic linking, like C<AIX> and C<OS/2>. It is a bug of C<Berkeley DB>
be771a83 415which is left unnoticed if C<DB> uses I<forgiving> system malloc().
a0d0e21e 416
aa689395
PP
417=item Bad hash
418
419(P) One of the internal hash routines was passed a null HV pointer.
420
6df41af2
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421=item Badly placed ()'s
422
423(A) You've accidentally run your script through B<csh> instead
424of Perl. Check the #! line, or manually feed your script into
425Perl yourself.
426
a7cb8dae 427=item Bad name after %s
a0d0e21e 428
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429(F) You started to name a symbol by using a package prefix, and then
430didn't finish the symbol. In particular, you can't interpolate outside
431of quotes, so
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432
433 $var = 'myvar';
434 $sym = mypack::$var;
435
436is not the same as
437
438 $var = 'myvar';
439 $sym = "mypack::$var";
440
88e1f1a2
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441=item Bad plugin affecting keyword '%s'
442
443(F) An extension using the keyword plugin mechanism violated the
444plugin API.
445
4ad56ec9
IZ
446=item Bad realloc() ignored
447
6903afa2
FC
448(S malloc) An internal routine called realloc() on something that
449had never been malloc()ed in the first place. Mandatory, but can
450be disabled by setting the environment variable C<PERL_BADFREE> to 1.
4ad56ec9 451
a0d0e21e
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452=item Bad symbol for array
453
454(P) An internal request asked to add an array entry to something that
455wasn't a symbol table entry.
456
4df3f177
SP
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.
a0d0e21e
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466
467=item Bad symbol for hash
468
469(P) An internal request asked to add a hash entry to something that
470wasn't a symbol table entry.
471
34d09196
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472=item Bareword found in conditional
473
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474(W bareword) The compiler found a bareword where it expected a
475conditional, which often indicates that an || or && was parsed as part
476of the last argument of the previous construct, for example:
34d09196
GS
477
478 open FOO || die;
479
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480It may also indicate a misspelled constant that has been interpreted as
481a bareword:
34d09196
GS
482
483 use constant TYPO => 1;
484 if (TYOP) { print "foo" }
485
486The C<strict> pragma is useful in avoiding such errors.
487
6df41af2
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488=item Bareword "%s" not allowed while "strict subs" in use
489
490(F) With "strict subs" in use, a bareword is only allowed as a
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491subroutine identifier, in curly brackets or to the left of the "=>"
492symbol. Perhaps you need to predeclare a subroutine?
6df41af2
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493
494=item Bareword "%s" refers to nonexistent package
495
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496(W bareword) You used a qualified bareword of the form C<Foo::>, but the
497compiler saw no other uses of that namespace before that point. Perhaps
498you need to predeclare a package?
6df41af2 499
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500=item BEGIN failed--compilation aborted
501
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502(F) An untrapped exception was raised while executing a BEGIN
503subroutine. Compilation stops immediately and the interpreter is
504exited.
a0d0e21e 505
68dc0745
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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
JH
522=item Binary number > 0b11111111111111111111111111111111 non-portable
523
e476b1b5 524(W portable) The binary number you specified is larger than 2**32-1
9e24b6e2
JH
525(4294967295) and therefore non-portable between systems. See
526L<perlport> for more on portability concerns.
252aa082 527
69282e91 528=item bind() on closed socket %s
a0d0e21e 529
be771a83
GS
530(W closed) You tried to do a bind on a closed socket. Did you forget to
531check the return value of your socket() call? See L<perlfunc/bind>.
a0d0e21e 532
c289d2f7
JH
533=item binmode() on closed filehandle %s
534
535(W unopened) You tried binmode() on a filehandle that was never opened.
4dcecea4 536Check your control flow and number of arguments.
c289d2f7 537
c5a0f51a
JH
538=item Bit vector size > 32 non-portable
539
e476b1b5 540(W portable) Using bit vector sizes larger than 32 is non-portable.
c5a0f51a 541
043c750c 542=item Bizarre copy of %s
4633a7c4 543
be771a83 544(P) Perl detected an attempt to copy an internal value that is not
ab830aa0 545copiable.
4633a7c4 546
5a25739d
FC
547=item Bizarre SvTYPE [%d]
548
434f489b 549(P) When starting a new thread or returning values from a thread, Perl
5a25739d
FC
550encountered an invalid data type.
551
f675dbe5
CB
552=item Buffer overflow in prime_env_iter: %s
553
be771a83
GS
554(W internal) A warning peculiar to VMS. While Perl was preparing to
555iterate over %ENV, it encountered a logical name or symbol definition
556which was too long, so it was truncated to the string shown.
f675dbe5 557
a0d0e21e
LW
558=item Callback called exit
559
4929bf7b 560(F) A subroutine invoked from an external package via call_sv()
a0d0e21e
LW
561exited by calling exit.
562
6df41af2 563=item %s() called too early to check prototype
f675dbe5 564
be771a83
GS
565(W prototype) You've called a function that has a prototype before the
566parser saw a definition or declaration for it, and Perl could not check
567that the call conforms to the prototype. You need to either add an
568early prototype declaration for the subroutine in question, or move the
569subroutine definition ahead of the call to get proper prototype
570checking. Alternatively, if you are certain that you're calling the
571function correctly, you may put an ampersand before the name to avoid
572the warning. See L<perlsub>.
f675dbe5 573
56feebad
FC
574=item Calling POSIX::%s() is deprecated
575
576(D deprecated) You called a function whose use is deprecated. See
577the function's name in L<POSIX> for details.
578
0c7df902
JH
579=item Cannot chr %f
580
581(F) You passed an invalid number (like an infinity or not-a-number) to C<chr>.
582
5dee29d4 583=item Cannot compress %f in pack
0c7df902 584
5dee29d4
JH
585(F) You tried compressing an infinity or not-a-number as an unsigned
586integer with BER, which makes no sense.
0c7df902 587
49704364 588=item Cannot compress integer in pack
0258719b 589
717feafc
JH
590(F) An argument to pack("w",...) was too large to compress.
591The BER compressed integer format can only be used with positive
592integers, and you attempted to compress a very large number (> 1e308).
593See L<perlfunc/pack>.
0258719b 594
49704364 595=item Cannot compress negative numbers in pack
0258719b
NC
596
597(F) An argument to pack("w",...) was negative. The BER compressed integer
598format can only be used with positive integers. See L<perlfunc/pack>.
599
5c1f4d79
NC
600=item Cannot convert a reference to %s to typeglob
601
6903afa2
FC
602(F) You manipulated Perl's symbol table directly, stored a reference
603in it, then tried to access that symbol via conventional Perl syntax.
604The access triggers Perl to autovivify that typeglob, but it there is
605no legal conversion from that type of reference to a typeglob.
5c1f4d79 606
4040665a 607=item Cannot copy to %s
ba2fdce6
NC
608
609(P) Perl detected an attempt to copy a value to an internal type that cannot
4dcecea4 610be directly assigned to.
ba2fdce6 611
b5d97229
RGS
612=item Cannot find encoding "%s"
613
614(S io) You tried to apply an encoding that did not exist to a filehandle,
615either with open() or binmode().
616
0c7df902
JH
617=item Cannot pack %f with '%c'
618
5dee29d4 619(F) You tried converting an infinity or not-a-number to an integer,
0c7df902
JH
620which makes no sense.
621
622=item Cannot printf %f with '%c'
623
624(F) You tried printing an infinity or not-a-number as a character (%c),
625which makes no sense. Maybe you meant '%s', or just stringifying it?
626
7355df7e
FC
627=item Cannot set tied @DB::args
628
629(F) C<caller> tried to set C<@DB::args>, but found it tied. Tying C<@DB::args>
630is not supported. (Before this error was added, it used to crash.)
631
ce65bc73
FC
632=item Cannot tie unreifiable array
633
634(P) You somehow managed to call C<tie> on an array that does not
635keep a reference count on its arguments and cannot be made to
636do so. Such arrays are not even supposed to be accessible to
637Perl code, but are only used internally.
638
96ebfdd7
RK
639=item Can only compress unsigned integers in pack
640
641(F) An argument to pack("w",...) was not an integer. The BER compressed
642integer format can only be used with positive integers, and you attempted
643to compress something else. See L<perlfunc/pack>.
644
a0d0e21e
LW
645=item Can't bless non-reference value
646
647(F) Only hard references may be blessed. This is how Perl "enforces"
648encapsulation of objects. See L<perlobj>.
649
dc57907a
RGS
650=item Can't "break" in a loop topicalizer
651
0d863452 652(F) You called C<break>, but you're in a C<foreach> block rather than
6903afa2 653a C<given> block. You probably meant to use C<next> or C<last>.
0d863452
RH
654
655=item Can't "break" outside a given block
dc57907a 656
0d863452
RH
657(F) You called C<break>, but you're not inside a C<given> block.
658
6df41af2
GS
659=item Can't call method "%s" on an undefined value
660
661(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
662object reference or package name contains an undefined value. Something
663like this will reproduce the error:
6df41af2
GS
664
665 $BADREF = undef;
666 process $BADREF 1,2,3;
667 $BADREF->process(1,2,3);
668
a0d0e21e
LW
669=item Can't call method "%s" on unblessed reference
670
54310121 671(F) A method call must know in what package it's supposed to run. It
be771a83
GS
672ordinarily finds this out from the object reference you supply, but you
673didn't supply an object reference in this case. A reference isn't an
674object reference until it has been blessed. See L<perlobj>.
a0d0e21e
LW
675
676=item Can't call method "%s" without a package or object reference
677
678(F) You used the syntax of a method call, but the slot filled by the
be771a83
GS
679object reference or package name contains an expression that returns a
680defined value which is neither an object reference nor a package name.
72b5445b
GS
681Something like this will reproduce the error:
682
683 $BADREF = 42;
684 process $BADREF 1,2,3;
685 $BADREF->process(1,2,3);
686
dfe378f1
FC
687=item Can't call mro_isa_changed_in() on anonymous symbol table
688
689(P) Perl got confused as to whether a hash was a plain hash or a
690symbol table hash when trying to update @ISA caches.
691
2bf7e7b2
FC
692=item Can't call mro_method_changed_in() on anonymous symbol table
693
694(F) An XS module tried to call C<mro_method_changed_in> on a hash that was
695not attached to the symbol table.
696
a0d0e21e
LW
697=item Can't chdir to %s
698
f703fc96 699(F) You called C<perl -x/foo/bar>, but F</foo/bar> is not a directory
a0d0e21e
LW
700that you can chdir to, possibly because it doesn't exist.
701
0545a864 702=item Can't check filesystem of script "%s" for nosuid
104d25b7 703
be771a83
GS
704(P) For some reason you can't check the filesystem of the script for
705nosuid.
104d25b7 706
22e74366 707=item Can't coerce %s to %s in %s
a0d0e21e
LW
708
709(F) Certain types of SVs, in particular real symbol table entries
55497cff 710(typeglobs), can't be forced to stop being what they are. So you can't
a0d0e21e
LW
711say things like:
712
713 *foo += 1;
714
715You CAN say
716
717 $foo = *foo;
718 $foo += 1;
719
720but then $foo no longer contains a glob.
721
0d863452 722=item Can't "continue" outside a when block
dc57907a 723
0d863452
RH
724(F) You called C<continue>, but you're not inside a C<when>
725or C<default> block.
726
a0d0e21e
LW
727=item Can't create pipe mailbox
728
be771a83
GS
729(P) An error peculiar to VMS. The process is suffering from exhausted
730quotas or other plumbing problems.
a0d0e21e 731
eb64745e
GS
732=item Can't declare %s in "%s"
733
30c282f6
NC
734(F) Only scalar, array, and hash variables may be declared as "my", "our" or
735"state" variables. They must have ordinary identifiers as names.
a0d0e21e 736
fc7debfb
FC
737=item Can't "default" outside a topicalizer
738
739(F) You have used a C<default> block that is neither inside a
740C<foreach> loop nor a C<given> block. (Note that this error is
741issued on exit from the C<default> block, so you won't get the
742error if you use an explicit C<continue>.)
743
6df41af2
GS
744=item Can't do inplace edit: %s is not a regular file
745
be771a83 746(S inplace) You tried to use the B<-i> switch on a special file, such as
df7075a8 747a file in /dev, a FIFO or an uneditable directory. The file was ignored.
6df41af2 748
a0d0e21e
LW
749=item Can't do inplace edit on %s: %s
750
be771a83
GS
751(S inplace) The creation of the new file failed for the indicated
752reason.
a0d0e21e 753
54310121 754=item Can't do inplace edit without backup
a0d0e21e 755
be771a83
GS
756(F) You're on a system such as MS-DOS that gets confused if you try
757reading from a deleted (but still opened) file. You have to say
758C<-i.bak>, or some such.
a0d0e21e 759
10f9c03d 760=item Can't do inplace edit: %s would not be unique
a0d0e21e 761
e476b1b5 762(S inplace) Your filesystem does not support filenames longer than 14
10f9c03d
CK
763characters and Perl was unable to create a unique filename during
764inplace editing with the B<-i> switch. The file was ignored.
a0d0e21e 765
a0d0e21e
LW
766=item Can't do waitpid with flags
767
be771a83
GS
768(F) This machine doesn't have either waitpid() or wait4(), so only
769waitpid() without flags is emulated.
a0d0e21e 770
a0d0e21e
LW
771=item Can't emulate -%s on #! line
772
be771a83
GS
773(F) The #! line specifies a switch that doesn't make sense at this
774point. For example, it'd be kind of silly to put a B<-x> on the #!
775line.
a0d0e21e 776
1109a392
MHM
777=item Can't %s %s-endian %ss on this platform
778
779(F) Your platform's byte-order is neither big-endian nor little-endian,
780or it has a very strange pointer size. Packing and unpacking big- or
781little-endian floating point values and pointers may not be possible.
782See L<perlfunc/pack>.
783
a0d0e21e
LW
784=item Can't exec "%s": %s
785
d1be9408 786(W exec) A system(), exec(), or piped open call could not execute the
be771a83
GS
787named program for the indicated reason. Typical reasons include: the
788permissions were wrong on the file, the file wasn't found in
789C<$ENV{PATH}>, the executable in question was compiled for another
790architecture, or the #! line in a script points to an interpreter that
791can't be run for similar reasons. (Or maybe your system doesn't support
792#! at all.)
a0d0e21e
LW
793
794=item Can't exec %s
795
be771a83
GS
796(F) Perl was trying to execute the indicated program for you because
797that's what the #! line said. If that's not what you wanted, you may
798need to mention "perl" on the #! line somewhere.
a0d0e21e
LW
799
800=item Can't execute %s
801
be771a83
GS
802(F) You used the B<-S> switch, but the copies of the script to execute
803found in the PATH did not have correct permissions.
2a92aaa0 804
6df41af2 805=item Can't find an opnumber for "%s"
2a92aaa0 806
be771a83
GS
807(F) A string of a form C<CORE::word> was given to prototype(), but there
808is no builtin with the name C<word>.
6df41af2 809
56ca2fc0
JH
810=item Can't find %s character property "%s"
811
812(F) You used C<\p{}> or C<\P{}> but the character property by that name
6903afa2 813could not be found. Maybe you misspelled the name of the property?
e1b711da 814See L<perluniprops/Properties accessible through \p{} and \P{}>
9b73678d 815for a complete list of available official properties.
56ca2fc0 816
6df41af2
GS
817=item Can't find label %s
818
be771a83
GS
819(F) You said to goto a label that isn't mentioned anywhere that it's
820possible for us to go to. See L<perlfunc/goto>.
2a92aaa0
GS
821
822=item Can't find %s on PATH
823
be771a83
GS
824(F) You used the B<-S> switch, but the script to execute could not be
825found in the PATH.
a0d0e21e 826
6df41af2 827=item Can't find %s on PATH, '.' not in PATH
a0d0e21e 828
be771a83
GS
829(F) You used the B<-S> switch, but the script to execute could not be
830found in the PATH, or at least not with the correct permissions. The
831script exists in the current directory, but PATH prohibits running it.
a0d0e21e
LW
832
833=item Can't find string terminator %s anywhere before EOF
834
be771a83
GS
835(F) Perl strings can stretch over multiple lines. This message means
836that the closing delimiter was omitted. Because bracketed quotes count
837nesting levels, the following is missing its final parenthesis:
a0d0e21e 838
fb73857a
PP
839 print q(The character '(' starts a side comment.);
840
97b3d10f 841If you're getting this error from a here-document, you may have
b6b8cb97
FC
842included unseen whitespace before or after your closing tag or there
843may not be a linebreak after it. A good programmer's editor will have
844a way to help you find these characters (or lack of characters). See
845L<perlop> for the full details on here-documents.
a0d0e21e 846
660a4616
ST
847=item Can't find Unicode property definition "%s"
848
5f8ad6b6
FC
849(F) You may have tried to use C<\p> which means a Unicode
850property (for example C<\p{Lu}> matches all uppercase
fa816bf3 851letters). If you did mean to use a Unicode property, see
e1b711da 852L<perluniprops/Properties accessible through \p{} and \P{}>
6903afa2 853for a complete list of available properties. If you didn't
fa816bf3
FC
854mean to use a Unicode property, escape the C<\p>, either by
855C<\\p> (just the C<\p>) or by C<\Q\p> (the rest of the string, or
5f8ad6b6 856until C<\E>).
660a4616 857
b3647a36 858=item Can't fork: %s
a0d0e21e 859
be771a83
GS
860(F) A fatal error occurred while trying to fork while opening a
861pipeline.
a0d0e21e 862
b3647a36
SR
863=item Can't fork, trying again in 5 seconds
864
c973c02e 865(W pipe) A fork in a piped open failed with EAGAIN and will be retried
b3647a36
SR
866after five seconds.
867
748a9306
LW
868=item Can't get filespec - stale stat buffer?
869
be771a83
GS
870(S) A warning peculiar to VMS. This arises because of the difference
871between access checks under VMS and under the Unix model Perl assumes.
872Under VMS, access checks are done by filename, rather than by bits in
873the stat buffer, so that ACLs and other protections can be taken into
874account. Unfortunately, Perl assumes that the stat buffer contains all
875the necessary information, and passes it, instead of the filespec, to
2fe2bdfd 876the access-checking routine. It will try to retrieve the filespec using
be771a83
GS
877the device name and FID present in the stat buffer, but this works only
878if you haven't made a subsequent call to the CRTL stat() routine,
879because the device name is overwritten with each call. If this warning
2fe2bdfd
FC
880appears, the name lookup failed, and the access-checking routine gave up
881and returned FALSE, just to be conservative. (Note: The access-checking
be771a83
GS
882routine knows about the Perl C<stat> operator and file tests, so you
883shouldn't ever see this warning in response to a Perl command; it arises
884only if some internal code takes stat buffers lightly.)
748a9306 885
a0d0e21e
LW
886=item Can't get pipe mailbox device name
887
be771a83
GS
888(P) An error peculiar to VMS. After creating a mailbox to act as a
889pipe, Perl can't retrieve its name for later use.
a0d0e21e
LW
890
891=item Can't get SYSGEN parameter value for MAXBUF
892
748a9306
LW
893(P) An error peculiar to VMS. Perl asked $GETSYI how big you want your
894mailbox buffers to be, and didn't get an answer.
a0d0e21e 895
6df41af2 896=item Can't "goto" into the middle of a foreach loop
a0d0e21e 897
be771a83
GS
898(F) A "goto" statement was executed to jump into the middle of a foreach
899loop. You can't get there from here. See L<perlfunc/goto>.
6df41af2
GS
900
901=item Can't "goto" out of a pseudo block
902
be771a83
GS
903(F) A "goto" statement was executed to jump out of what might look like
904a block, except that it isn't a proper block. This usually occurs if
905you tried to jump out of a sort() block or subroutine, which is a no-no.
906See L<perlfunc/goto>.
a0d0e21e 907
5a25739d
FC
908=item Can't goto subroutine from an eval-%s
909
910(F) The "goto subroutine" call can't be used to jump out of an eval
911"string" or block.
912
9850bf21 913=item Can't goto subroutine from a sort sub (or similar callback)
cd299c6e 914
9850bf21
RH
915(F) The "goto subroutine" call can't be used to jump out of the
916comparison sub for a sort(), or from a similar callback (such
917as the reduce() function in List::Util).
918
6df41af2
GS
919=item Can't goto subroutine outside a subroutine
920
be771a83
GS
921(F) The deeply magical "goto subroutine" call can only replace one
922subroutine call for another. It can't manufacture one out of whole
923cloth. In general you should be calling it out of only an AUTOLOAD
924routine anyway. See L<perlfunc/goto>.
6df41af2 925
0b5b802d
GS
926=item Can't ignore signal CHLD, forcing to default
927
be771a83
GS
928(W signal) Perl has detected that it is being run with the SIGCHLD
929signal (sometimes known as SIGCLD) disabled. Since disabling this
930signal will interfere with proper determination of exit status of child
931processes, Perl has reset the signal to its default value. This
932situation typically indicates that the parent program under which Perl
933may be running (e.g. cron) is being very careless.
0b5b802d 934
e2c0f81f
DG
935=item Can't kill a non-numeric process ID
936
937(F) Process identifiers must be (signed) integers. It is a fatal error to
938attempt to kill() an undefined, empty-string or otherwise non-numeric
939process identifier.
940
6df41af2 941=item Can't "last" outside a loop block
4633a7c4 942
6df41af2 943(F) A "last" statement was executed to break out of the current block,
be771a83
GS
944except that there's this itty bitty problem called there isn't a current
945block. Note that an "if" or "else" block doesn't count as a "loopish"
946block, as doesn't a block given to sort(), map() or grep(). You can
947usually double the curlies to get the same effect though, because the
948inner curlies will be considered a block that loops once. See
949L<perlfunc/last>.
4633a7c4 950
2c7d6b9c
RGS
951=item Can't linearize anonymous symbol table
952
953(F) Perl tried to calculate the method resolution order (MRO) of a
954package, but failed because the package stash has no name.
955
b8170e59
JB
956=item Can't load '%s' for module %s
957
6903afa2
FC
958(F) The module you tried to load failed to load a dynamic extension.
959This may either mean that you upgraded your version of perl to one
960that is incompatible with your old dynamic extensions (which is known
961to happen between major versions of perl), or (more likely) that your
962dynamic extension was built against an older version of the library
963that is installed on your system. You may need to rebuild your old
964dynamic extensions.
b8170e59 965
748a9306
LW
966=item Can't localize lexical variable %s
967
2ba9eb46 968(F) You used local on a variable name that was previously declared as a
b7e4ecc1
FC
969lexical variable using "my" or "state". This is not allowed. If you
970want to localize a package variable of the same name, qualify it with
971the package name.
748a9306 972
6df41af2 973=item Can't localize through a reference
4727527e 974
6df41af2
GS
975(F) You said something like C<local $$ref>, which Perl can't currently
976handle, because when it goes to restore the old value of whatever $ref
be771a83 977pointed to after the scope of the local() is finished, it can't be sure
64977eb6 978that $ref will still be a reference.
4727527e 979
ea071790 980=item Can't locate %s
ec889f3a 981
fa816bf3
FC
982(F) You said to C<do> (or C<require>, or C<use>) a file that couldn't be found.
983Perl looks for the file in all the locations mentioned in @INC, unless
984the file name included the full path to the file. Perhaps you need
985to set the PERL5LIB or PERL5OPT environment variable to say where the
986extra library is, or maybe the script needs to add the library name
be771a83
GS
987to @INC. Or maybe you just misspelled the name of the file. See
988L<perlfunc/require> and L<lib>.
a0d0e21e 989
6df41af2
GS
990=item Can't locate auto/%s.al in @INC
991
be771a83
GS
992(F) A function (or method) was called in a package which allows
993autoload, but there is no function to autoload. Most probable causes
994are a misprint in a function/method name or a failure to C<AutoSplit>
995the file, say, by doing C<make install>.
6df41af2 996
b8170e59
JB
997=item Can't locate loadable object for module %s in @INC
998
999(F) The module you loaded is trying to load an external library, like
d70d8e57 1000for example, F<foo.so> or F<bar.dll>, but the L<DynaLoader> module was
b8170e59
JB
1001unable to locate this library. See L<DynaLoader>.
1002
a0d0e21e
LW
1003=item Can't locate object method "%s" via package "%s"
1004
1005(F) You called a method correctly, and it correctly indicated a package
1006functioning as a class, but that package doesn't define that particular
2ba9eb46 1007method, nor does any of its base classes. See L<perlobj>.
a0d0e21e 1008
8af56b9d
FC
1009=item Can't locate object method "%s" via package "%s" (perhaps you forgot
1010to load "%s"?)
1011
1012(F) You called a method on a class that did not exist, and the method
1013could not be found in UNIVERSAL. This often means that a method
1014requires a package that has not been loaded.
1015
a0d0e21e
LW
1016=item Can't locate package %s for @%s::ISA
1017
be771a83
GS
1018(W syntax) The @ISA array contained the name of another package that
1019doesn't seem to exist.
a0d0e21e 1020
2f7da168
RK
1021=item Can't locate PerlIO%s
1022
1023(F) You tried to use in open() a PerlIO layer that does not exist,
1024e.g. open(FH, ">:nosuchlayer", "somefile").
1025
f4ad53f4 1026=item Can't make list assignment to %ENV on this system
3e3baf6d 1027
be771a83
GS
1028(F) List assignment to %ENV is not supported on some systems, notably
1029VMS.
3e3baf6d 1030
cd40cd58
NC
1031=item Can't make loaded symbols global on this platform while loading %s
1032
ff9c1ae8 1033(S) A module passed the flag 0x01 to DynaLoader::dl_load_file() to request
cd40cd58
NC
1034that symbols from the stated file are made available globally within the
1035process, but that functionality is not available on this platform. Whilst
1036the module likely will still work, this may prevent the perl interpreter
1037from loading other XS-based extensions which need to link directly to
1038functions defined in the C or XS code in the stated file.
1039
a0d0e21e
LW
1040=item Can't modify %s in %s
1041
be771a83
GS
1042(F) You aren't allowed to assign to the item indicated, or otherwise try
1043to change it, such as with an auto-increment.
a0d0e21e 1044
54310121 1045=item Can't modify nonexistent substring
a0d0e21e
LW
1046
1047(P) The internal routine that does assignment to a substr() was handed
1048a NULL.
1049
6df41af2
GS
1050=item Can't modify non-lvalue subroutine call
1051
1052(F) Subroutines meant to be used in lvalue context should be declared as
2fe2bdfd 1053such. See L<perlsub/"Lvalue subroutines">.
6df41af2 1054
cf6e1fa1
FC
1055=item Can't modify reference to %s in %s assignment
1056
1057(F) Only a limited number of constructs can be used as the argument to a
1058reference constructor on the left-hand side of an assignment, and what
1059you used was not one of them. See L<perlref/Assigning to References>.
1060
1061=item Can't modify reference to localized parenthesized array in list
1062assignment
1063
1064(F) Assigning to C<\local(@array)> or C<\(local @array)> is not supported, as
1065it is not clear exactly what it should do. If you meant to make @array
1066refer to some other array, use C<\@array = \@other_array>. If you want to
1067make the elements of @array aliases of the scalars referenced on the
1068right-hand side, use C<\(@array) = @scalar_refs>.
1069
1070=item Can't modify reference to parenthesized hash in list assignment
1071
1072(F) Assigning to C<\(%hash)> is not supported. If you meant to make %hash
1073refer to some other hash, use C<\%hash = \%other_hash>. If you want to
1074make the elements of %hash into aliases of the scalars referenced on the
1075right-hand side, use a hash slice: C<\@hash{@keys} = @those_scalar_refs>.
1076
5f05dabc 1077=item Can't msgrcv to read-only var
a0d0e21e 1078
5f05dabc 1079(F) The target of a msgrcv must be modifiable to be used as a receive
a0d0e21e
LW
1080buffer.
1081
6df41af2
GS
1082=item Can't "next" outside a loop block
1083
1084(F) A "next" statement was executed to reiterate the current block, but
1085there isn't a current block. Note that an "if" or "else" block doesn't
be771a83
GS
1086count as a "loopish" block, as doesn't a block given to sort(), map() or
1087grep(). You can usually double the curlies to get the same effect
1088though, because the inner curlies will be considered a block that loops
1089once. See L<perlfunc/next>.
6df41af2 1090
a0d0e21e
LW
1091=item Can't open %s: %s
1092
c47ff5f1 1093(S inplace) The implicit opening of a file through use of the C<< <> >>
08e9d68e 1094filehandle, either implicitly under the C<-n> or C<-p> command-line
46fa9b26
FC
1095switches, or explicitly, failed for the indicated reason. Usually
1096this is because you don't have read permission for a file which
1097you named on the command line.
1098
1099(F) You tried to call perl with the B<-e> switch, but F</dev/null> (or
1100your operating system's equivalent) could not be opened.
a0d0e21e 1101
9a869a14
RGS
1102=item Can't open a reference
1103
1104(W io) You tried to open a scalar reference for reading or writing,
2fe2bdfd 1105using the 3-arg open() syntax:
9a869a14
RGS
1106
1107 open FH, '>', $ref;
1108
1109but your version of perl is compiled without perlio, and this form of
1110open is not supported.
1111
a0d0e21e
LW
1112=item Can't open bidirectional pipe
1113
be771a83
GS
1114(W pipe) You tried to say C<open(CMD, "|cmd|")>, which is not supported.
1115You can try any of several modules in the Perl library to do this, such
1116as IPC::Open2. Alternately, direct the pipe's output to a file using
1117">", and then read it in under a different file handle.
a0d0e21e 1118
748a9306
LW
1119=item Can't open error file %s as stderr
1120
be771a83
GS
1121(F) An error peculiar to VMS. Perl does its own command line
1122redirection, and couldn't open the file specified after '2>' or '2>>' on
1123the command line for writing.
748a9306
LW
1124
1125=item Can't open input file %s as stdin
1126
be771a83
GS
1127(F) An error peculiar to VMS. Perl does its own command line
1128redirection, and couldn't open the file specified after '<' on the
1129command line for reading.
748a9306
LW
1130
1131=item Can't open output file %s as stdout
1132
be771a83
GS
1133(F) An error peculiar to VMS. Perl does its own command line
1134redirection, and couldn't open the file specified after '>' or '>>' on
1135the command line for writing.
748a9306
LW
1136
1137=item Can't open output pipe (name: %s)
1138
be771a83
GS
1139(P) An error peculiar to VMS. Perl does its own command line
1140redirection, and couldn't open the pipe into which to send data destined
1141for stdout.
748a9306 1142
3b1cf97d 1143=item Can't open perl script "%s": %s
a0d0e21e
LW
1144
1145(F) The script you specified can't be opened for the indicated reason.
1146
fa3aa65a
JC
1147If you're debugging a script that uses #!, and normally relies on the
1148shell's $PATH search, the -S option causes perl to do that search, so
1149you don't have to type the path or C<`which $scriptname`>.
1150
6df41af2
GS
1151=item Can't read CRTL environ
1152
1153(S) A warning peculiar to VMS. Perl tried to read an element of %ENV
1154from the CRTL's internal environment array and discovered the array was
1155missing. You need to figure out where your CRTL misplaced its environ
be771a83
GS
1156or define F<PERL_ENV_TABLES> (see L<perlvms>) so that environ is not
1157searched.
6df41af2 1158
6df41af2
GS
1159=item Can't "redo" outside a loop block
1160
1161(F) A "redo" statement was executed to restart the current block, but
1162there isn't a current block. Note that an "if" or "else" block doesn't
1163count as a "loopish" block, as doesn't a block given to sort(), map()
1164or grep(). You can usually double the curlies to get the same effect
1165though, because the inner curlies will be considered a block that
1166loops once. See L<perlfunc/redo>.
1167
64977eb6 1168=item Can't remove %s: %s, skipping file
10f9c03d 1169
be771a83
GS
1170(S inplace) You requested an inplace edit without creating a backup
1171file. Perl was unable to remove the original file to replace it with
1172the modified file. The file was left unmodified.
10f9c03d 1173
a0d0e21e
LW
1174=item Can't rename %s to %s: %s, skipping file
1175
e476b1b5 1176(S inplace) The rename done by the B<-i> switch failed for some reason,
10f9c03d 1177probably because you don't have write permission to the directory.
a0d0e21e 1178
748a9306
LW
1179=item Can't reopen input pipe (name: %s) in binary mode
1180
be771a83
GS
1181(P) An error peculiar to VMS. Perl thought stdin was a pipe, and tried
1182to reopen it to accept binary data. Alas, it failed.
748a9306 1183
9415f659
KW
1184=item Can't represent character for Ox%X on this platform
1185
1186(F) There is a hard limit to how big a character code point can be due
1187to the fundamental properties of UTF-8, especially on EBCDIC
1188platforms. The given code point exceeds that. The only work-around is
1189to not use such a large code point.
1190
4f12ec0e
FC
1191=item Can't reset %ENV on this system
1192
1193(F) You called C<reset('E')> or similar, which tried to reset
1194all variables in the current package beginning with "E". In
1195the main package, that includes %ENV. Resetting %ENV is not
1196supported on some systems, notably VMS.
1197
fe13d51d 1198=item Can't resolve method "%s" overloading "%s" in package "%s"
6df41af2 1199
1fa582fa
FC
1200(F)(P) Error resolving overloading specified by a method name (as
1201opposed to a subroutine reference): no such method callable via the
1202package. If the method name is C<???>, this is an internal error.
6df41af2 1203
cd06dffe
GS
1204=item Can't return %s from lvalue subroutine
1205
be771a83
GS
1206(F) Perl detected an attempt to return illegal lvalues (such as
1207temporary or readonly values) from a subroutine used as an lvalue. This
1208is not allowed.
cd06dffe 1209
96ebfdd7
RK
1210=item Can't return outside a subroutine
1211
1212(F) The return statement was executed in mainline code, that is, where
1213there was no subroutine call to return out of. See L<perlsub>.
1214
78f9721b
SM
1215=item Can't return %s to lvalue scalar context
1216
6903afa2
FC
1217(F) You tried to return a complete array or hash from an lvalue
1218subroutine, but you called the subroutine in a way that made Perl
1219think you meant to return only one value. You probably meant to
1220write parentheses around the call to the subroutine, which tell
1221Perl that the call should be in list context.
78f9721b 1222
a0d0e21e
LW
1223=item Can't stat script "%s"
1224
be771a83
GS
1225(P) For some reason you can't fstat() the script even though you have it
1226open already. Bizarre.
a0d0e21e 1227
a0d0e21e
LW
1228=item Can't take log of %g
1229
fb73857a 1230(F) For ordinary real numbers, you can't take the logarithm of a
6903afa2 1231negative number or zero. There's a Math::Complex package that comes
be771a83
GS
1232standard with Perl, though, if you really want to do that for the
1233negative numbers.
a0d0e21e
LW
1234
1235=item Can't take sqrt of %g
1236
1237(F) For ordinary real numbers, you can't take the square root of a
fb73857a
PP
1238negative number. There's a Math::Complex package that comes standard
1239with Perl, though, if you really want to do that.
a0d0e21e
LW
1240
1241=item Can't undef active subroutine
1242
1243(F) You can't undefine a routine that's currently running. You can,
1244however, redefine it while it's running, and you can even undef the
1245redefined subroutine while the old routine is running. Go figure.
1246
c81225bc 1247=item Can't upgrade %s (%d) to %d
a0d0e21e 1248
be771a83
GS
1249(P) The internal sv_upgrade routine adds "members" to an SV, making it
1250into a more specialized kind of SV. The top several SV types are so
1251specialized, however, that they cannot be interconverted. This message
1252indicates that such a conversion was attempted.
a0d0e21e 1253
6651ba0b
FC
1254=item Can't use '%c' after -mname
1255
1256(F) You tried to call perl with the B<-m> switch, but you put something
1257other than "=" after the module name.
1258
1f1ec7b5
KW
1259=item Can't use a hash as a reference
1260
1261(F) You tried to use a hash as a reference, as in
66a1f5ec
FC
1262C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl
1263<= 5.22.0 used to allow this syntax, but shouldn't
1264have. This was deprecated in perl 5.6.1.
1f1ec7b5
KW
1265
1266=item Can't use an array as a reference
1267
1268(F) You tried to use an array as a reference, as in
66a1f5ec
FC
1269C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.22.0
1270used to allow this syntax, but shouldn't have. This
1271was deprecated in perl 5.6.1.
1f1ec7b5 1272
1db89ea5
BS
1273=item Can't use anonymous symbol table for method lookup
1274
e27ad1f2 1275(F) The internal routine that does method lookup was handed a symbol
1db89ea5
BS
1276table that doesn't have a name. Symbol tables can become anonymous
1277for example by undefining stashes: C<undef %Some::Package::>.
1278
96ebfdd7
RK
1279=item Can't use an undefined value as %s reference
1280
1281(F) A value used as either a hard reference or a symbolic reference must
1282be a defined value. This helps to delurk some insidious errors.
1283
6df41af2
GS
1284=item Can't use bareword ("%s") as %s ref while "strict refs" in use
1285
be771a83
GS
1286(F) Only hard references are allowed by "strict refs". Symbolic
1287references are disallowed. See L<perlref>.
6df41af2 1288
90b75b61 1289=item Can't use %! because Errno.pm is not available
1d2dff63 1290
20561843 1291(F) The first time the C<%!> hash is used, perl automatically loads the
6903afa2 1292Errno.pm module. The Errno module is expected to tie the %! hash to
1d2dff63
GS
1293provide symbolic names for C<$!> errno values.
1294
1109a392
MHM
1295=item Can't use both '<' and '>' after type '%c' in %s
1296
1297(F) A type cannot be forced to have both big-endian and little-endian
1298byte-order at the same time, so this combination of modifiers is not
1299allowed. See L<perlfunc/pack>.
1300
e35475de
KW
1301=item Can't use 'defined(@array)' (Maybe you should just omit the defined()?)
1302
1303(F) defined() is not useful on arrays because it
1304checks for an undefined I<scalar> value. If you want to see if the
1305array is empty, just use C<if (@array) { # not empty }> for example.
1306
1307=item Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)
1308
1309(F) C<defined()> is not usually right on hashes.
1310
1311Although C<defined %hash> is false on a plain not-yet-used hash, it
1312becomes true in several non-obvious circumstances, including iterators,
1313weak references, stash names, even remaining true after C<undef %hash>.
1314These things make C<defined %hash> fairly useless in practice, so it now
1315generates a fatal error.
1316
1317If a check for non-empty is what you wanted then just put it in boolean
1318context (see L<perldata/Scalar values>):
1319
1320 if (%hash) {
1321 # not empty
1322 }
1323
1324If you had C<defined %Foo::Bar::QUUX> to check whether such a package
1325variable exists then that's never really been reliable, and isn't
1326a good way to enquire about the features of a package, or whether
1327it's loaded, etc.
1328
6df41af2
GS
1329=item Can't use %s for loop variable
1330
be771a83
GS
1331(F) Only a simple scalar variable may be used as a loop variable on a
1332foreach.
6df41af2 1333
aab6a793 1334=item Can't use global %s in "%s"
6df41af2 1335
be771a83
GS
1336(F) You tried to declare a magical variable as a lexical variable. This
1337is not allowed, because the magic can be tied to only one location
1338(namely the global variable) and it would be incredibly confusing to
1339have variables in your program that looked like magical variables but
6df41af2
GS
1340weren't.
1341
6d3b25aa
RGS
1342=item Can't use '%c' in a group with different byte-order in %s
1343
1344(F) You attempted to force a different byte-order on a type
1345that is already inside a group with a byte-order modifier.
1346For example you cannot force little-endianness on a type that
1347is inside a big-endian group.
1348
c07a80fd
PP
1349=item Can't use "my %s" in sort comparison
1350
1351(F) The global variables $a and $b are reserved for sort comparisons.
c47ff5f1 1352You mentioned $a or $b in the same line as the <=> or cmp operator,
c07a80fd
PP
1353and the variable had earlier been declared as a lexical variable.
1354Either qualify the sort variable with the package name, or rename the
1355lexical variable.
1356
a0d0e21e
LW
1357=item Can't use %s ref as %s ref
1358
1359(F) You've mixed up your reference types. You have to dereference a
1360reference of the type needed. You can use the ref() function to
1361test the type of the reference, if need be.
1362
748a9306 1363=item Can't use string ("%s") as %s ref while "strict refs" in use
a0d0e21e 1364
5e634d20
FC
1365=item Can't use string ("%s"...) as %s ref while "strict refs" in use
1366
b41bf23f
FC
1367(F) You've told Perl to dereference a string, something which
1368C<use strict> blocks to prevent it happening accidentally. See
1369L<perlref/"Symbolic references">. This can be triggered by an C<@> or C<$>
1370in a double-quoted string immediately before interpolating a variable,
1371for example in C<"user @$twitter_id">, which says to treat the contents
1372of C<$twitter_id> as an array reference; use a C<\> to have a literal C<@>
1373symbol followed by the contents of C<$twitter_id>: C<"user \@$twitter_id">.
a0d0e21e 1374
748a9306
LW
1375=item Can't use subscript on %s
1376
1377(F) The compiler tried to interpret a bracketed expression as a
1378subscript. But to the left of the brackets was an expression that
209e7cf1 1379didn't look like a hash or array reference, or anything else subscriptable.
748a9306 1380
6df41af2
GS
1381=item Can't use \%c to mean $%c in expression
1382
75b44862
GS
1383(W syntax) In an ordinary expression, backslash is a unary operator that
1384creates a reference to its argument. The use of backslash to indicate a
1385backreference to a matched substring is valid only as part of a regular
be771a83
GS
1386expression pattern. Trying to do this in ordinary Perl code produces a
1387value that prints out looking like SCALAR(0xdecaf). Use the $1 form
1388instead.
6df41af2 1389
810b8aa5
GS
1390=item Can't weaken a nonreference
1391
1392(F) You attempted to weaken something that was not a reference. Only
1393references can be weakened.
1394
fc7debfb
FC
1395=item Can't "when" outside a topicalizer
1396
1397(F) You have used a when() block that is neither inside a C<foreach>
1398loop nor a C<given> block. (Note that this error is issued on exit
1399from the C<when> block, so you won't get the error if the match fails,
1400or if you use an explicit C<continue>.)
1401
5f05dabc 1402=item Can't x= to read-only value
a0d0e21e 1403
be771a83
GS
1404(F) You tried to repeat a constant value (often the undefined value)
1405with an assignment operator, which implies modifying the value itself.
a0d0e21e
LW
1406Perhaps you need to copy the value to a temporary, and repeat that.
1407
a04e6aad 1408=item Character following "\c" must be printable ASCII
f9d13529 1409
7357bd17 1410(F) In C<\cI<X>>, I<X> must be a printable (non-control) ASCII character.
17a3df4c 1411
727b6379 1412Note that ASCII characters that don't map to control characters are
7357bd17 1413discouraged, and will generate the warning (when enabled)
727b6379 1414L</""\c%c" is more clearly written simply as "%s"">.
f9d13529 1415
f337b084 1416=item Character in 'C' format wrapped in pack
ac7cd81a
SC
1417
1418(W pack) You said
1419
1420 pack("C", $x)
1421
1422where $x is either less than 0 or more than 255; the C<"C"> format is
1423only for encoding native operating system characters (ASCII, EBCDIC,
1424and so on) and not for Unicode characters, so Perl behaved as if you meant
1425
1426 pack("C", $x & 255)
1427
1428If you actually want to pack Unicode codepoints, use the C<"U"> format
1429instead.
1430
f337b084 1431=item Character in 'c' format wrapped in pack
ac7cd81a
SC
1432
1433(W pack) You said
1434
1435 pack("c", $x)
1436
1437where $x is either less than -128 or more than 127; the C<"c"> format
1438is only for encoding native operating system characters (ASCII, EBCDIC,
1439and so on) and not for Unicode characters, so Perl behaved as if you meant
1440
1441 pack("c", $x & 255);
1442
1443If you actually want to pack Unicode codepoints, use the C<"U"> format
1444instead.
1445
f337b084
TH
1446=item Character in '%c' format wrapped in unpack
1447
1448(W unpack) You tried something like
1449
1450 unpack("H", "\x{2a1}")
1451
1a147d38 1452where the format expects to process a byte (a character with a value
6903afa2
FC
1453below 256), but a higher value was provided instead. Perl uses the
1454value modulus 256 instead, as if you had provided:
f337b084
TH
1455
1456 unpack("H", "\x{a1}")
1457
5a25739d
FC
1458=item Character in 'W' format wrapped in pack
1459
1460(W pack) You said
1461
1462 pack("U0W", $x)
1463
1464where $x is either less than 0 or more than 255. However, C<U0>-mode
1465expects all values to fall in the interval [0, 255], so Perl behaved
1466as if you meant:
1467
1468 pack("U0W", $x & 255)
1469
f337b084
TH
1470=item Character(s) in '%c' format wrapped in pack
1471
1472(W pack) You tried something like
1473
1474 pack("u", "\x{1f3}b")
1475
1a147d38 1476where the format expects to process a sequence of bytes (character with a
6903afa2 1477value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1478uses the character values modulus 256 instead, as if you had provided:
1479
1480 pack("u", "\x{f3}b")
1481
1482=item Character(s) in '%c' format wrapped in unpack
1483
1484(W unpack) You tried something like
1485
1486 unpack("s", "\x{1f3}b")
1487
1a147d38 1488where the format expects to process a sequence of bytes (character with a
6903afa2 1489value below 256), but some of the characters had a higher value. Perl
f337b084
TH
1490uses the character values modulus 256 instead, as if you had provided:
1491
1492 unpack("s", "\x{f3}b")
1493
f51551f7
FC
1494=item charnames alias definitions may not contain a sequence of multiple spaces
1495
1496(F) You defined a character name which had multiple space characters
1497in a row. Change them to single spaces. Usually these names are
1498defined in the C<:alias> import argument to C<use charnames>, but they
1499could be defined by a translator installed into C<$^H{charnames}>. See
1500L<charnames/CUSTOM ALIASES>.
1501
1502=item charnames alias definitions may not contain trailing white-space
1503
1504(F) You defined a character name which ended in a space
1505character. Remove the trailing space(s). Usually these names are
1506defined in the C<:alias> import argument to C<use charnames>, but they
1507could be defined by a translator installed into C<$^H{charnames}>.
1508See L<charnames/CUSTOM ALIASES>.
1509
1510=item \C is deprecated in regex; marked by <-- HERE in m/%s/
1511
1512(D deprecated, regexp) The \C character class is deprecated, and will
1513become a compile-time error in a future release of perl (tentatively
3617dbb6
FC
1514v5.24). This construct allows you to match a single byte of what makes
1515up a multi-byte single UTF8 character, and breaks encapsulation. It is
1516currently also very buggy. If you really need to process the individual
f51551f7
FC
1517bytes, you probably want to convert your string to one where each
1518underlying byte is stored as a character, with utf8::encode().
1519
f866a7cd
FC
1520=item "\c%c" is more clearly written simply as "%s"
1521
1522(W syntax) The C<\cI<X>> construct is intended to be a way to specify
7ed0dd93
FC
1523non-printable characters. You used it for a printable one, which
1524is better written as simply itself, perhaps preceded by a backslash
1525for non-word characters. Doing it the way you did is not portable
1526between ASCII and EBCDIC platforms.
f866a7cd 1527
6651ba0b
FC
1528=item Cloning substitution context is unimplemented
1529
1530(F) Creating a new thread inside the C<s///> operator is not supported.
1531
abc7ecad
SP
1532=item closedir() attempted on invalid dirhandle %s
1533
1534(W io) The dirhandle you tried to close is either closed or not really
1535a dirhandle. Check your control flow.
1536
5a25739d
FC
1537=item close() on unopened filehandle %s
1538
1539(W unopened) You tried to close a filehandle that was never opened.
1540
541ed3a9
FC
1541=item Closure prototype called
1542
1543(F) If a closure has attributes, the subroutine passed to an attribute
1544handler is the prototype that is cloned when a new closure is created.
1545This subroutine cannot be called.
1546
49704364
LW
1547=item Code missing after '/'
1548
6903afa2
FC
1549(F) You had a (sub-)template that ends with a '/'. There must be
1550another template code following the slash. See L<perlfunc/pack>.
49704364 1551
5a25739d
FC
1552=item Code point 0x%X is not Unicode, may not be portable
1553
2d88a86a 1554(S non_unicode) You had a code point above the Unicode maximum
1b64326b
FC
1555of U+10FFFF.
1556
1557Perl allows strings to contain a superset of Unicode code points, up
1558to the limit of what is storable in an unsigned integer on your system,
1559but these may not be accepted by other languages/systems. At one time,
1560it was legal in some standards to have code points up to 0x7FFF_FFFF,
1561but not higher. Code points above 0xFFFF_FFFF require larger than a
156232 bit word.
0876b9a0 1563
6df41af2
GS
1564=item %s: Command not found
1565
a892b81a 1566(A) You've accidentally run your script through B<csh> or another shell
66a1f5ec
FC
1567instead of Perl. Check the #! line, or manually feed your script into
1568Perl yourself. The #! line at the top of your file could look like
8f721816
MM
1569
1570 #!/usr/bin/perl -w
6df41af2 1571
7a2e2cd6
PP
1572=item Compilation failed in require
1573
1574(F) Perl could not compile a file specified in a C<require> statement.
be771a83
GS
1575Perl uses this generic message when none of the errors that it
1576encountered were severe enough to halt compilation immediately.
7a2e2cd6 1577
c3464db5
DD
1578=item Complex regular subexpression recursion limit (%d) exceeded
1579
be771a83
GS
1580(W regexp) The regular expression engine uses recursion in complex
1581situations where back-tracking is required. Recursion depth is limited
1582to 32766, or perhaps less in architectures where the stack cannot grow
1583arbitrarily. ("Simple" and "medium" situations are handled without
1584recursion and are not subject to a limit.) Try shortening the string
1585under examination; looping in Perl code (e.g. with C<while>) rather than
1586in the regular expression engine; or rewriting the regular expression so
c2e66d9e 1587that it is simpler or backtracks less. (See L<perlfaq2> for information
be771a83 1588on I<Mastering Regular Expressions>.)
c3464db5 1589
69282e91 1590=item connect() on closed socket %s
a0d0e21e 1591
be771a83
GS
1592(W closed) You tried to do a connect on a closed socket. Did you forget
1593to check the return value of your socket() call? See
1594L<perlfunc/connect>.
a0d0e21e 1595
e21e7c6a
FC
1596=item Constant(%s): Call to &{$^H{%s}} did not return a defined value
1597
1598(F) The subroutine registered to handle constant overloading
1599(see L<overload>) or a custom charnames handler (see
1600L<charnames/CUSTOM TRANSLATORS>) returned an undefined value.
1601
1602=item Constant(%s): $^H{%s} is not defined
1603
1604(F) The parser found inconsistencies while attempting to define an
1605overloaded constant. Perhaps you forgot to load the corresponding
f738a371 1606L<overload> pragma?
e21e7c6a 1607
779c5bc9
GS
1608=item Constant is not %s reference
1609
1610(F) A constant value (perhaps declared using the C<use constant> pragma)
be771a83 1611is being dereferenced, but it amounts to the wrong type of reference.
6903afa2 1612The message indicates the type of reference that was expected. This
be771a83 1613usually indicates a syntax error in dereferencing the constant value.
779c5bc9
GS
1614See L<perlsub/"Constant Functions"> and L<constant>.
1615
0ac016fc
FC
1616=item Constants from lexical variables potentially modified elsewhere are
1617deprecated
1618
1619(D deprecated) You wrote something like
1620
1621 my $var;
1622 $sub = sub () { $var };
1623
1624but $var is referenced elsewhere and could be modified after the C<sub>
1625expression is evaluated. Either it is explicitly modified elsewhere
1626(C<$var = 3>) or it is passed to a subroutine or to an operator like
1627C<printf> or C<map>, which may or may not modify the variable.
1628
1629Traditionally, Perl has captured the value of the variable at that
1630point and turned the subroutine into a constant eligible for inlining.
1631In those cases where the variable can be modified elsewhere, this
1632breaks the behavior of closures, in which the subroutine captures
1633the variable itself, rather than its value, so future changes to the
1634variable are reflected in the subroutine's return value.
1635
1636This usage is deprecated, because the behavior is likely to change
1637in a future version of Perl.
1638
1639If you intended for the subroutine to be eligible for inlining, then
1640make sure the variable is not referenced elsewhere, possibly by
1641copying it:
1642
1643 my $var2 = $var;
1644 $sub = sub () { $var2 };
1645
1646If you do want this subroutine to be a closure that reflects future
1647changes to the variable that it closes over, add an explicit C<return>:
1648
1649 my $var;
1650 $sub = sub () { return $var };
1651
4cee8e80
CS
1652=item Constant subroutine %s redefined
1653
aeb94125
FC
1654(W redefine)(S) You redefined a subroutine which had previously
1655been eligible for inlining. See L<perlsub/"Constant Functions">
1656for commentary and workarounds.
4cee8e80 1657
9607fc9c
PP
1658=item Constant subroutine %s undefined
1659
be771a83
GS
1660(W misc) You undefined a subroutine which had previously been eligible
1661for inlining. See L<perlsub/"Constant Functions"> for commentary and
1662workarounds.
9607fc9c 1663
5a25739d
FC
1664=item Constant(%s) unknown
1665
1666(F) The parser found inconsistencies either while attempting
1667to define an overloaded constant, or when trying to find the
1668character name specified in the C<\N{...}> escape. Perhaps you
1669forgot to load the corresponding L<overload> pragma?.
1670
e7ea3e70
IZ
1671=item Copy method did not return a reference
1672
6903afa2 1673(F) The method which overloads "=" is buggy. See
13a2d996 1674L<overload/Copy Constructor>.
e7ea3e70 1675
4aaa4757
FC
1676=item &CORE::%s cannot be called directly
1677
1678(F) You tried to call a subroutine in the C<CORE::> namespace
8d605c0d 1679with C<&foo> syntax or through a reference. Some subroutines
4aaa4757
FC
1680in this package cannot yet be called that way, but must be
1681called as barewords. Something like this will work:
1682
1683 BEGIN { *shove = \&CORE::push; }
1684 shove @array, 1,2,3; # pushes on to @array
1685
6798c92b
GS
1686=item CORE::%s is not a keyword
1687
1688(F) The CORE:: namespace is reserved for Perl keywords.
1689
675fa9ff
FC
1690=item Corrupted regexp opcode %d > %d
1691
1692(P) This is either an error in Perl, or, if you're using
1693one, your L<custom regular expression engine|perlreapi>. If not the
1694latter, report the problem through the L<perlbug> utility.
1695
a0d0e21e
LW
1696=item corrupted regexp pointers
1697
1698(P) The regular expression engine got confused by what the regular
1699expression compiler gave it.
1700
1701=item corrupted regexp program
1702
be771a83
GS
1703(P) The regular expression engine got passed a regexp program without a
1704valid magic number.
a0d0e21e 1705
de42a5a9 1706=item Corrupt malloc ptr 0x%x at 0x%x
6df41af2
GS
1707
1708(P) The malloc package that comes with Perl had an internal failure.
1709
49704364
LW
1710=item Count after length/code in unpack
1711
1712(F) You had an unpack template indicating a counted-length string, but
1713you have also specified an explicit size for the string. See
1714L<perlfunc/pack>.
1715
f2cccb4c
KW
1716=for comment
1717The following are used in lib/diagnostics.t for testing two =items that
1718share the same description. Changes here need to be propagated to there
1719
6651ba0b
FC
1720=item Deep recursion on anonymous subroutine
1721
a0d0e21e
LW
1722=item Deep recursion on subroutine "%s"
1723
be771a83
GS
1724(W recursion) This subroutine has called itself (directly or indirectly)
1725100 times more than it has returned. This probably indicates an
1726infinite recursion, unless you're writing strange benchmark programs, in
1727which case it indicates something else.
a0d0e21e 1728
aad1d01f
NC
1729This threshold can be changed from 100, by recompiling the F<perl> binary,
1730setting the C pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1731
e0e4a6e3
FC
1732=item (?(DEFINE)....) does not allow branches in regex; marked by
1733S<<-- HERE> in m/%s/
bcb95744 1734
6903afa2 1735(F) You used something like C<(?(DEFINE)...|..)> which is illegal. The
bcb95744
FC
1736most likely cause of this error is that you left out a parenthesis inside
1737of the C<....> part.
1738
9e3ec65c 1739The <-- HERE shows whereabouts in the regular expression the problem was
bcb95744
FC
1740discovered.
1741
62658f4d
PM
1742=item %s defines neither package nor VERSION--version check failed
1743
1744(F) You said something like "use Module 42" but in the Module file
1745there are neither package declarations nor a C<$VERSION>.
1746
36447869
FC
1747=item delete argument is index/value array slice, use array slice
1748
1749(F) You used index/value array slice syntax (C<%array[...]>) as
1750the argument to C<delete>. You probably meant C<@array[...]> with
1751an @ symbol instead.
1752
1753=item delete argument is key/value hash slice, use hash slice
1754
1755(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
1756C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
1757
0ffcbc25
FC
1758=item delete argument is not a HASH or ARRAY element or slice
1759
4a0af295 1760(F) The argument to C<delete> must be either a hash or array element,
0ffcbc25
FC
1761such as:
1762
1763 $foo{$bar}
1764 $ref->{"susie"}[12]
1765
1766or a hash or array slice, such as:
1767
1768 @foo[$bar, $baz, $xyzzy]
1769 @{$ref->[12]}{"susie", "queue"}
1770
fc36a67e
PP
1771=item Delimiter for here document is too long
1772
be771a83
GS
1773(F) In a here document construct like C<<<FOO>, the label C<FOO> is too
1774long for Perl to handle. You have to be seriously twisted to write code
1775that triggers this error.
fc36a67e 1776
6d3b25aa
RGS
1777=item Deprecated use of my() in false conditional
1778
fa816bf3
FC
1779(D deprecated) You used a declaration similar to C<my $x if 0>. There
1780has been a long-standing bug in Perl that causes a lexical variable
6d3b25aa 1781not to be cleared at scope exit when its declaration includes a false
6903afa2 1782conditional. Some people have exploited this bug to achieve a kind of
fa816bf3 1783static variable. Since we intend to fix this bug, we don't want people
6903afa2 1784relying on this behavior. You can achieve a similar static effect by
6d3b25aa 1785declaring the variable in a separate block outside the function, eg
36fb85f3 1786
6d3b25aa
RGS
1787 sub f { my $x if 0; return $x++ }
1788
1789becomes
1790
1791 { my $x; sub f { return $x++ } }
1792
ea9d9ebc 1793Beginning with perl 5.10.0, you can also use C<state> variables to have
fa816bf3 1794lexicals that are initialized only once (see L<feature>):
36fb85f3
RGS
1795
1796 sub f { state $x; return $x++ }
1797
500ab966
RGS
1798=item DESTROY created new reference to dead object '%s'
1799
1800(F) A DESTROY() method created a new reference to the object which is
6903afa2
FC
1801just being DESTROYed. Perl is confused, and prefers to abort rather
1802than to create a dangling reference.
500ab966 1803
3cdd684c
TP
1804=item Did not produce a valid header
1805
1806See Server error.
1807
6df41af2
GS
1808=item %s did not return a true value
1809
1810(F) A required (or used) file must return a true value to indicate that
1811it compiled correctly and ran its initialization code correctly. It's
1812traditional to end such a file with a "1;", though any true value would
1813do. See L<perlfunc/require>.
1814
cc507455 1815=item (Did you mean &%s instead?)
4633a7c4 1816
413ff9f6
FC
1817(W misc) You probably referred to an imported subroutine &FOO as $FOO or
1818some such.
4633a7c4 1819
cc507455 1820=item (Did you mean "local" instead of "our"?)
33633739 1821
be771a83
GS
1822(W misc) Remember that "our" does not localize the declared global
1823variable. You have declared it again in the same lexical scope, which
1824seems superfluous.
33633739 1825
cc507455 1826=item (Did you mean $ or @ instead of %?)
a0d0e21e 1827
be771a83
GS
1828(W) You probably said %hash{$key} when you meant $hash{$key} or
1829@hash{@keys}. On the other hand, maybe you just meant %hash and got
1830carried away.
748a9306 1831
7e1af8bc 1832=item Died
5f05dabc
PP
1833
1834(F) You passed die() an empty string (the equivalent of C<die "">) or
075b00aa 1835you called it with no args and C<$@> was empty.
5f05dabc 1836
3cdd684c
TP
1837=item Document contains no data
1838
1839See Server error.
1840
62658f4d
PM
1841=item %s does not define %s::VERSION--version check failed
1842
1843(F) You said something like "use Module 42" but the Module did not
943fc58e 1844define a C<$VERSION>.
62658f4d 1845
49704364
LW
1846=item '/' does not take a repeat count
1847
1848(F) You cannot put a repeat count of any kind right after the '/' code.
1849See L<perlfunc/pack>.
1850
95cb0d72
FC
1851=item Don't know how to get file name
1852
1853(P) C<PerlIO_getname>, a perl internal I/O function specific to VMS, was
1854somehow called on another platform. This should not happen.
1855
4021c788 1856=item Don't know how to handle magic of type \%o
a0d0e21e
LW
1857
1858(P) The internal handling of magical variables has been cursed.
1859
1860=item do_study: out of memory
1861
1862(P) This should have been caught by safemalloc() instead.
1863
6df41af2
GS
1864=item (Do you need to predeclare %s?)
1865
56da5a46
RGS
1866(S syntax) This is an educated guess made in conjunction with the message
1867"%s found where operator expected". It often means a subroutine or module
6df41af2
GS
1868name is being referenced that hasn't been declared yet. This may be
1869because of ordering problems in your file, or because of a missing
be771a83
GS
1870"sub", "package", "require", or "use" statement. If you're referencing
1871something that isn't defined yet, you don't actually have to define the
1872subroutine or package before the current location. You can use an empty
1873"sub foo;" or "package FOO;" to enter a "forward" declaration.
6df41af2 1874
ac206dc8
RGS
1875=item dump() better written as CORE::dump()
1876
1877(W misc) You used the obsolescent C<dump()> built-in function, without fully
1878qualifying it as C<CORE::dump()>. Maybe it's a typo. See L<perlfunc/dump>.
1879
84d78eb7
YO
1880=item dump is not supported
1881
1882(F) Your machine doesn't support dump/undump.
1883
a0d0e21e
LW
1884=item Duplicate free() ignored
1885
be771a83
GS
1886(S malloc) An internal routine called free() on something that had
1887already been freed.
a0d0e21e 1888
1109a392
MHM
1889=item Duplicate modifier '%c' after '%c' in %s
1890
35f0cd76
FC
1891(W unpack) You have applied the same modifier more than once after a
1892type in a pack template. See L<perlfunc/pack>.
1109a392 1893
0953b66b
FC
1894=item each on reference is experimental
1895
0773cb3e
FC
1896(S experimental::autoderef) C<each> with a scalar argument is experimental
1897and may change or be removed in a future Perl version. If you want to
1898take the risk of using this feature, simply disable this warning:
0953b66b 1899
d401967c 1900 no warnings "experimental::autoderef";
0953b66b 1901
4633a7c4
LW
1902=item elseif should be elsif
1903
fa816bf3
FC
1904(S syntax) There is no keyword "elseif" in Perl because Larry thinks
1905it's ugly. Your code will be interpreted as an attempt to call a method
1906named "elseif" for the class returned by the following block. This is
4633a7c4
LW
1907unlikely to be what you want.
1908
e0e4a6e3 1909=item Empty \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 1910
af6f566e 1911(F) C<\p> and C<\P> are used to introduce a named Unicode property, as
6903afa2 1912described in L<perlunicode> and L<perlre>. You used C<\p> or C<\P> in
af6f566e 1913a regular expression without specifying the property name.
ab13f0c7 1914
85ab1d1d 1915=item entering effective %s failed
5ff3f7a4 1916
85ab1d1d 1917(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
1918effective uids or gids failed.
1919
c038024b
RGS
1920=item %ENV is aliased to %s
1921
1922(F) You're running under taint mode, and the C<%ENV> variable has been
1923aliased to another hash, so it doesn't reflect anymore the state of the
6903afa2 1924program's environment. This is potentially insecure.
c038024b 1925
748a9306
LW
1926=item Error converting file specification %s
1927
5f05dabc 1928(F) An error peculiar to VMS. Because Perl may have to deal with file
748a9306 1929specifications in either VMS or Unix syntax, it converts them to a
be771a83
GS
1930single form when it must operate on them directly. Either you've passed
1931an invalid file specification to Perl, or you've found a case the
1932conversion routines don't handle. Drat.
748a9306 1933
ad19ef22 1934=item Eval-group in insecure regular expression
e4d48cc9 1935
be771a83
GS
1936(F) Perl detected tainted data when trying to compile a regular
1937expression that contains the C<(?{ ... })> zero-width assertion, which
1938is unsafe. See L<perlre/(?{ code })>, and L<perlsec>.
e4d48cc9 1939
ad19ef22 1940=item Eval-group not allowed at runtime, use re 'eval' in regex m/%s/
e4d48cc9 1941
be771a83
GS
1942(F) Perl tried to compile a regular expression containing the
1943C<(?{ ... })> zero-width assertion at run time, as it would when the
f11307f5
FC
1944pattern contains interpolated values. Since that is a security risk,
1945it is not allowed. If you insist, you may still do this by using the
1946C<re 'eval'> pragma or by explicitly building the pattern from an
1947interpolated string at run time and using that in an eval(). See
1948L<perlre/(?{ code })>.
e4d48cc9 1949
ad19ef22 1950=item Eval-group not allowed, use re 'eval' in regex m/%s/
6df41af2 1951
be771a83
GS
1952(F) A regular expression contained the C<(?{ ... })> zero-width
1953assertion, but that construct is only allowed when the C<use re 'eval'>
1954pragma is in effect. See L<perlre/(?{ code })>.
6df41af2 1955
e0e4a6e3
FC
1956=item EVAL without pos change exceeded limit in regex; marked by
1957S<<-- HERE> in m/%s/
1a147d38
YO
1958
1959(F) You used a pattern that nested too many EVAL calls without consuming
6903afa2 1960any text. Restructure the pattern so that text is consumed.
1a147d38 1961
9e3ec65c 1962The <-- HERE shows whereabouts in the regular expression the problem was
1a147d38
YO
1963discovered.
1964
fc36a67e
PP
1965=item Excessively long <> operator
1966
1967(F) The contents of a <> operator may not exceed the maximum size of a
1968Perl identifier. If you're just trying to glob a long list of
1969filenames, try using the glob() operator, or put the filenames into a
1970variable and glob that.
1971
ed9aa3b7
SG
1972=item exec? I'm not *that* kind of operating system
1973
af8bb25a 1974(F) The C<exec> function is not implemented on some systems, e.g., Symbian
6903afa2 1975OS. See L<perlport>.
ed9aa3b7 1976
fe13d51d 1977=item Execution of %s aborted due to compilation errors.
a0d0e21e
LW
1978
1979(F) The final summary message when a Perl compilation fails.
1980
0ffcbc25
FC
1981=item exists argument is not a HASH or ARRAY element or a subroutine
1982
4a0af295 1983(F) The argument to C<exists> must be a hash or array element or a
0ffcbc25
FC
1984subroutine with an ampersand, such as:
1985
1986 $foo{$bar}
1987 $ref->{"susie"}[12]
1988 &do_something
1989
1990=item exists argument is not a subroutine name
1991
ccfc2567
FC
1992(F) The argument to C<exists> for C<exists &sub> must be a subroutine name,
1993and not a subroutine call. C<exists &sub()> will generate this error.
0ffcbc25 1994
a0d0e21e
LW
1995=item Exiting eval via %s
1996
be771a83
GS
1997(W exiting) You are exiting an eval by unconventional means, such as a
1998goto, or a loop control statement.
e476b1b5
GS
1999
2000=item Exiting format via %s
2001
9a2ff54b 2002(W exiting) You are exiting a format by unconventional means, such as a
be771a83 2003goto, or a loop control statement.
a0d0e21e 2004
0a753a76
PP
2005=item Exiting pseudo-block via %s
2006
be771a83
GS
2007(W exiting) You are exiting a rather special block construct (like a
2008sort block or subroutine) by unconventional means, such as a goto, or a
2009loop control statement. See L<perlfunc/sort>.
0a753a76 2010
a0d0e21e
LW
2011=item Exiting subroutine via %s
2012
be771a83
GS
2013(W exiting) You are exiting a subroutine by unconventional means, such
2014as a goto, or a loop control statement.
a0d0e21e
LW
2015
2016=item Exiting substitution via %s
2017
be771a83
GS
2018(W exiting) You are exiting a substitution by unconventional means, such
2019as a return, a goto, or a loop control statement.
a0d0e21e 2020
e0e4a6e3 2021=item Expecting close bracket in regex; marked by S<<-- HERE> in m/%s/
c608e803 2022
675fa9ff 2023(F) You wrote something like
c608e803
KW
2024
2025 (?13
2026
2027to denote a capturing group of the form
2028L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>,
2029but omitted the C<")">.
2030
e0e4a6e3 2031=item Expecting '(?flags:(?[...' in regex; marked by S<<-- HERE> in m/%s/
27350048 2032
8b6fbf55
FC
2033(F) The C<(?[...])> extended character class regular expression construct
2034only allows character classes (including character class escapes like
2035C<\d>), operators, and parentheses. The one exception is C<(?flags:...)>
2036containing at least one flag and exactly one C<(?[...])> construct.
27350048
FC
2037This allows a regular expression containing just C<(?[...])> to be
2038interpolated. If you see this error message, then you probably
2039have some other C<(?...)> construct inside your character class. See
2040L<perlrecharclass/Extended Bracketed Character Classes>.
2041
baabe3fb 2042=item Experimental aliasing via reference not enabled
1f8155a2 2043
baabe3fb 2044(F) To do aliasing via references, you must first enable the feature:
1f8155a2 2045
baabe3fb
FC
2046 no warnings "experimental::refaliasing";
2047 use feature "refaliasing";
1f8155a2
FC
2048 \$x = \$y;
2049
30d9c59b
Z
2050=item Experimental subroutine signatures not enabled
2051
2052(F) To use subroutine signatures, you must first enable them:
2053
caa35032 2054 no warnings "experimental::signatures";
30d9c59b
Z
2055 use feature "signatures";
2056 sub foo ($left, $right) { ... }
2057
6da34ecb
FC
2058=item Experimental "%s" subs not enabled
2059
2060(F) To use lexical subs, you must first enable them:
2061
2062 no warnings 'experimental::lexical_subs';
2063 use feature 'lexical_subs';
2064 my sub foo { ... }
2065
7b8d334a
GS
2066=item Explicit blessing to '' (assuming package main)
2067
be771a83
GS
2068(W misc) You are blessing a reference to a zero length string. This has
2069the effect of blessing the reference into the package main. This is
2070usually not what you want. Consider providing a default target package,
2071e.g. bless($ref, $p || 'MyPackage');
7b8d334a 2072
6df41af2
GS
2073=item %s: Expression syntax
2074
be771a83
GS
2075(A) You've accidentally run your script through B<csh> instead of Perl.
2076Check the #! line, or manually feed your script into Perl yourself.
6df41af2
GS
2077
2078=item %s failed--call queue aborted
2079
3c10abe3
AG
2080(F) An untrapped exception was raised while executing a UNITCHECK,
2081CHECK, INIT, or END subroutine. Processing of the remainder of the
2082queue of such routines has been prematurely ended.
6df41af2 2083
e0e4a6e3 2084=item False [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
73b437c8 2085
98d31c73 2086(W regexp)(F) A character class range must start and end at a literal
7253e4e3 2087character, not another character class like C<\d> or C<[:alpha:]>. The "-"
3c6ca74a
FC
2088in your false range is interpreted as a literal "-". In a C<(?[...])>
2089construct, this is an error, rather than a warning. Consider quoting
e0e4a6e3 2090the "-", "\-". The S<<-- HERE> shows whereabouts in the regular expression
3c6ca74a 2091the problem was discovered. See L<perlre>.
73b437c8 2092
1b1ee2ef 2093=item Fatal VMS error (status=%d) at %s, line %d
a0d0e21e 2094
be771a83
GS
2095(P) An error peculiar to VMS. Something untoward happened in a VMS
2096system service or RTL routine; Perl's exit status should provide more
2097details. The filename in "at %s" and the line number in "line %d" tell
2098you which section of the Perl source code is distressed.
a0d0e21e
LW
2099
2100=item fcntl is not implemented
2101
2102(F) Your machine apparently doesn't implement fcntl(). What is this, a
2103PDP-11 or something?
2104
22846ab4
AB
2105=item FETCHSIZE returned a negative value
2106
2107(F) A tied array claimed to have a negative number of elements, which
2108is not possible.
2109
f337b084
TH
2110=item Field too wide in 'u' format in pack
2111
d8b5cc61 2112(W pack) Each line in an uuencoded string starts with a length indicator
6903afa2
FC
2113which can't encode values above 63. So there is no point in asking for
2114a line length bigger than that. Perl will behave as if you specified
5c96f6f7 2115C<u63> as the format.
f337b084 2116
af8c498a 2117=item Filehandle %s opened only for input
a0d0e21e 2118
6c8d78fb
HS
2119(W io) You tried to write on a read-only filehandle. If you intended
2120it to be a read-write filehandle, you needed to open it with "+<" or
2121"+>" or "+>>" instead of with "<" or nothing. If you intended only to
2122write the file, use ">" or ">>". See L<perlfunc/open>.
a0d0e21e 2123
af8c498a 2124=item Filehandle %s opened only for output
a0d0e21e 2125
6c8d78fb
HS
2126(W io) You tried to read from a filehandle opened only for writing, If
2127you intended it to be a read/write filehandle, you needed to open it
89a1bda8
FC
2128with "+<" or "+>" or "+>>" instead of with ">". If you intended only to
2129read from the file, use "<". See L<perlfunc/open>. Another possibility
2130is that you attempted to open filedescriptor 0 (also known as STDIN) for
2131output (maybe you closed STDIN earlier?).
97828cef
RGS
2132
2133=item Filehandle %s reopened as %s only for input
2134
2135(W io) You opened for reading a filehandle that got the same filehandle id
6903afa2 2136as STDOUT or STDERR. This occurred because you closed STDOUT or STDERR
97828cef
RGS
2137previously.
2138
2139=item Filehandle STDIN reopened as %s only for output
2140
2141(W io) You opened for writing a filehandle that got the same filehandle id
fa816bf3 2142as STDIN. This occurred because you closed STDIN previously.
a0d0e21e
LW
2143
2144=item Final $ should be \$ or $name
2145
2146(F) You must now decide whether the final $ in a string was meant to be
be771a83
GS
2147a literal dollar sign, or was meant to introduce a variable name that
2148happens to be missing. So you have to put either the backslash or the
2149name.
a0d0e21e 2150
56e90b21
GS
2151=item flock() on closed filehandle %s
2152
be771a83 2153(W closed) The filehandle you're attempting to flock() got itself closed
c289d2f7 2154some time before now. Check your control flow. flock() operates on
be771a83
GS
2155filehandles. Are you attempting to call flock() on a dirhandle by the
2156same name?
56e90b21 2157
6df41af2
GS
2158=item Format not terminated
2159
2160(F) A format must be terminated by a line with a solitary dot. Perl got
2161to the end of your file without finding such a line.
2162
a0d0e21e
LW
2163=item Format %s redefined
2164
e476b1b5 2165(W redefine) You redefined a format. To suppress this warning, say
a0d0e21e
LW
2166
2167 {
271595cc 2168 no warnings 'redefine';
a0d0e21e
LW
2169 eval "format NAME =...";
2170 }
2171
a0d0e21e
LW
2172=item Found = in conditional, should be ==
2173
e476b1b5 2174(W syntax) You said
a0d0e21e
LW
2175
2176 if ($foo = 123)
2177
2178when you meant
2179
2180 if ($foo == 123)
2181
2182(or something like that).
2183
6df41af2
GS
2184=item %s found where operator expected
2185
56da5a46
RGS
2186(S syntax) The Perl lexer knows whether to expect a term or an operator.
2187If it sees what it knows to be a term when it was expecting to see an
be771a83
GS
2188operator, it gives you this warning. Usually it indicates that an
2189operator or delimiter was omitted, such as a semicolon.
6df41af2 2190
a0d0e21e
LW
2191=item gdbm store returned %d, errno %d, key "%s"
2192
2193(S) A warning from the GDBM_File extension that a store failed.
2194
2195=item gethostent not implemented
2196
2197(F) Your C library apparently doesn't implement gethostent(), probably
2198because if it did, it'd feel morally obligated to return every hostname
2199on the Internet.
2200
69282e91 2201=item get%sname() on closed socket %s
a0d0e21e 2202
be771a83
GS
2203(W closed) You tried to get a socket or peer socket name on a closed
2204socket. Did you forget to check the return value of your socket() call?
a0d0e21e 2205
748a9306
LW
2206=item getpwnam returned invalid UIC %#o for user "%s"
2207
2208(S) A warning peculiar to VMS. The call to C<sys$getuai> underlying the
2209C<getpwnam> operator returned an invalid UIC.
2210
6df41af2
GS
2211=item getsockopt() on closed socket %s
2212
be771a83
GS
2213(W closed) You tried to get a socket option on a closed socket. Did you
2214forget to check the return value of your socket() call? See
6df41af2
GS
2215L<perlfunc/getsockopt>.
2216
0f539b13
BF
2217=item given is experimental
2218
675fa9ff
FC
2219(S experimental::smartmatch) C<given> depends on smartmatch, which
2220is experimental, so its behavior may change or even be removed
2221in any future release of perl. See the explanation under
2222L<perlsyn/Experimental Details on given and when>.
0f539b13 2223
68567d27
FC
2224=item Global symbol "%s" requires explicit package name (did you forget to
2225declare "my %s"?)
6df41af2 2226
a4edf47d 2227(F) You've said "use strict" or "use strict vars", which indicates
30c282f6 2228that all variables must either be lexically scoped (using "my" or "state"),
a4edf47d
GS
2229declared beforehand using "our", or explicitly qualified to say
2230which package the global variable is in (using "::").
6df41af2 2231
e476b1b5
GS
2232=item glob failed (%s)
2233
5ead438e 2234(S glob) Something went wrong with the external program(s) used
73c4e9dc
FC
2235for C<glob> and C<< <*.c> >>. Usually, this means that you supplied a C<glob>
2236pattern that caused the external program to fail and exit with a
be771a83 2237nonzero status. If the message indicates that the abnormal exit
73c4e9dc
FC
2238resulted in a coredump, this may also mean that your csh (C shell)
2239is broken. If so, you should change all of the csh-related variables
2240in config.sh: If you have tcsh, make the variables refer to it as
2241if it were csh (e.g. C<full_csh='/usr/bin/tcsh'>); otherwise, make them
2242all empty (except that C<d_csh> should be C<'undef'>) so that Perl will
be771a83 2243think csh is missing. In either case, after editing config.sh, run
75b44862 2244C<./Configure -S> and rebuild Perl.
e476b1b5 2245
a0d0e21e
LW
2246=item Glob not terminated
2247
2248(F) The lexer saw a left angle bracket in a place where it was expecting
be771a83
GS
2249a term, so it's looking for the corresponding right angle bracket, and
2250not finding it. Chances are you left some needed parentheses out
2251earlier in the line, and you really meant a "less than".
a0d0e21e 2252
b35b96b6
JH
2253=item gmtime(%f) failed
2254
2255(W overflow) You called C<gmtime> with a number that it could not handle:
2256too large, too small, or NaN. The returned value is C<undef>.
2257
bcd05b94 2258=item gmtime(%f) too large
8b56d6ff 2259
e9200be3 2260(W overflow) You called C<gmtime> with a number that was larger than
fc003d4b 2261it can reliably handle and C<gmtime> probably returned the wrong
6903afa2 2262date. This warning is also triggered with NaN (the special
fc003d4b
MS
2263not-a-number value).
2264
bcd05b94 2265=item gmtime(%f) too small
fc003d4b 2266
e9200be3 2267(W overflow) You called C<gmtime> with a number that was smaller than
e7a1a147 2268it can reliably handle and C<gmtime> probably returned the wrong date.
8b56d6ff 2269
6df41af2 2270=item Got an error from DosAllocMem
a0d0e21e 2271
6df41af2
GS
2272(P) An error peculiar to OS/2. Most probably you're using an obsolete
2273version of Perl, and this should not happen anyway.
a0d0e21e
LW
2274
2275=item goto must have label
2276
2277(F) Unlike with "next" or "last", you're not allowed to goto an
2278unspecified destination. See L<perlfunc/goto>.
2279
6651ba0b
FC
2280=item Goto undefined subroutine%s
2281
2282(F) You tried to call a subroutine with C<goto &sub> syntax, but
2283the indicated subroutine hasn't been defined, or if it was, it
2284has since been undefined.
2285
6fbc9859 2286=item Group name must start with a non-digit word character in regex; marked by
e0e4a6e3 2287S<<-- HERE> in m/%s/
1f4f6bf1
YO
2288
2289(F) Group names must follow the rules for perl identifiers, meaning
f26c79ba
FC
2290they must start with a non-digit word character. A common cause of
2291this error is using (?&0) instead of (?0). See L<perlre>.
1f4f6bf1 2292
5a25739d
FC
2293=item ()-group starts with a count
2294
2295(F) A ()-group started with a count. A count is supposed to follow
2296something: a template character or a ()-group. See L<perlfunc/pack>.
2297
fe13d51d 2298=item %s had compilation errors.
6df41af2
GS
2299
2300(F) The final summary message when a C<perl -c> fails.
2301
a0d0e21e
LW
2302=item Had to create %s unexpectedly
2303
be771a83
GS
2304(S internal) A routine asked for a symbol from a symbol table that ought
2305to have existed already, but for some reason it didn't, and had to be
2306created on an emergency basis to prevent a core dump.
a0d0e21e 2307
6df41af2
GS
2308=item %s has too many errors
2309
2310(F) The parser has given up trying to parse the program after 10 errors.
2311Further error messages would likely be uninformative.
2312
cc4d09e1
KW
2313=item Having more than one /%c regexp modifier is deprecated
2314
2315(D deprecated, regexp) You used the indicated regular expression pattern
2316modifier at least twice in a string of modifiers. It is deprecated to
2317do this with this particular modifier, to allow future extensions to the
2318Perl language.
2319
61e61fbc
JH
2320=item Hexadecimal float: exponent overflow
2321
d8f2b442 2322(W overflow) The hexadecimal floating point has a larger exponent
61e61fbc
JH
2323than the floating point supports.
2324
2325=item Hexadecimal float: exponent underflow
2326
d8f2b442 2327(W overflow) The hexadecimal floating point has a smaller exponent
61e61fbc
JH
2328than the floating point supports.
2329
cf4f6003
JH
2330=item Hexadecimal float: internal error
2331
2332(F) Something went horribly bad in hexadecimal float handling.
2333
61e61fbc
JH
2334=item Hexadecimal float: mantissa overflow
2335
2336(W overflow) The hexadecimal floating point literal had more bits in
2337the mantissa (the part between the 0x and the exponent, also known as
2338the fraction or the significand) than the floating point supports.
2339
40bca5ae
JH
2340=item Hexadecimal float: precision loss
2341
2342(W overflow) The hexadecimal floating point had internally more
2343digits than could be output. This can be caused by unsupported
2344long double formats, or by 64-bit integers not being available
2345(needed to retrieve the digits under some configurations).
2346
2347=item Hexadecimal float: unsupported long double format
2348
2349(F) You have configured Perl to use long doubles but
d8f2b442 2350the internals of the long double format are unknown;
40bca5ae
JH
2351therefore the hexadecimal float output is impossible.
2352
252aa082
JH
2353=item Hexadecimal number > 0xffffffff non-portable
2354
e476b1b5 2355(W portable) The hexadecimal number you specified is larger than 2**32-1
9e24b6e2
JH
2356(4294967295) and therefore non-portable between systems. See
2357L<perlport> for more on portability concerns.
252aa082 2358
8903cb82
PP
2359=item Identifier too long
2360
2361(F) Perl limits identifiers (names for variables, functions, etc.) to
fc36a67e 2362about 250 characters for simple names, and somewhat more for compound
be771a83
GS
2363names (like C<$A::B>). You've exceeded Perl's limits. Future versions
2364of Perl are likely to eliminate these arbitrary limitations.
8903cb82 2365
e0e4a6e3
FC
2366=item Ignoring zero length \N{} in character class in regex; marked by
2367S<<-- HERE> in m/%s/
fc8cd66c 2368
f3ba6905 2369(W regexp) Named Unicode character escapes (C<\N{...}>) may return a
0f44b2a5
FC
2370zero-length sequence. When such an escape is used in a character
2371class its behavior is not well defined. Check that the correct
2372escape has been used, and the correct charname handler is in scope.
fc8cd66c 2373
6df41af2 2374=item Illegal binary digit %s
f675dbe5 2375
6df41af2 2376(F) You used a digit other than 0 or 1 in a binary number.
f675dbe5 2377
6df41af2 2378=item Illegal binary digit %s ignored
a0d0e21e 2379
be771a83
GS
2380(W digit) You may have tried to use a digit other than 0 or 1 in a
2381binary number. Interpretation of the binary number stopped before the
2382offending digit.
a0d0e21e 2383
6597eb22
FC
2384=item Illegal character after '_' in prototype for %s : %s
2385
e4d150f1
FC
2386(W illegalproto) An illegal character was found in a prototype
2387declaration. The '_' in a prototype must be followed by a ';',
2388indicating the rest of the parameters are optional, or one of '@'
2389or '%', since those two will accept 0 or more final parameters.
6597eb22 2390
78d0fecf 2391=item Illegal character \%o (carriage return)
4fdae800 2392
d5898338 2393(F) Perl normally treats carriage returns in the program text as it
be771a83
GS
2394would any other whitespace, which means you should never see this error
2395when Perl was built using standard options. For some reason, your
2396version of Perl appears to have been built without this support. Talk
2397to your Perl administrator.
4fdae800 2398
d37a9538
ST
2399=item Illegal character in prototype for %s : %s
2400
197afce1 2401(W illegalproto) An illegal character was found in a prototype declaration.
2e9cc7ef 2402Legal characters in prototypes are $, @, %, *, ;, [, ], &, \, and +.
30d9c59b
Z
2403Perhaps you were trying to write a subroutine signature but didn't enable
2404that feature first (C<use feature 'signatures'>), so your signature was
2405instead interpreted as a bad prototype.
d37a9538 2406
904d85c5
RGS
2407=item Illegal declaration of anonymous subroutine
2408
2409(F) When using the C<sub> keyword to construct an anonymous subroutine,
6903afa2 2410you must always specify a block of code. See L<perlsub>.
904d85c5 2411
8e742a20
MHM
2412=item Illegal declaration of subroutine %s
2413
6903afa2 2414(F) A subroutine was not declared correctly. See L<perlsub>.
8e742a20 2415
a0d0e21e
LW
2416=item Illegal division by zero
2417
be771a83
GS
2418(F) You tried to divide a number by 0. Either something was wrong in
2419your logic, or you need to put a conditional in to guard against
2420meaningless input.
a0d0e21e 2421
6df41af2
GS
2422=item Illegal hexadecimal digit %s ignored
2423
be771a83
GS
2424(W digit) You may have tried to use a character other than 0 - 9 or
2425A - F, a - f in a hexadecimal number. Interpretation of the hexadecimal
2426number stopped before the illegal character.
6df41af2 2427
a0d0e21e
LW
2428=item Illegal modulus zero
2429
be771a83
GS
2430(F) You tried to divide a number by 0 to get the remainder. Most
2431numbers don't take to this kindly.
a0d0e21e 2432
6df41af2 2433=item Illegal number of bits in vec
399388f4 2434
6df41af2
GS
2435(F) The number of bits in vec() (the third argument) must be a power of
2436two from 1 to 32 (or 64, if your platform supports that).
399388f4
GS
2437
2438=item Illegal octal digit %s
a0d0e21e 2439
d1be9408 2440(F) You used an 8 or 9 in an octal number.
a0d0e21e 2441
399388f4 2442=item Illegal octal digit %s ignored
748a9306 2443
d1be9408 2444(W digit) You may have tried to use an 8 or 9 in an octal number.
75b44862 2445Interpretation of the octal number stopped before the 8 or 9.
748a9306 2446
e0e4a6e3 2447=item Illegal pattern in regex; marked by S<<-- HERE> in m/%s/
c608e803 2448
675fa9ff 2449(F) You wrote something like
c608e803
KW
2450
2451 (?+foo)
2452
2453The C<"+"> is valid only when followed by digits, indicating a
2454capturing group. See
2455L<C<(?I<PARNO>)>|perlre/(?PARNO) (?-PARNO) (?+PARNO) (?R) (?0)>.
2456
375ed12a
JH
2457=item Illegal suidscript
2458
2459(F) The script run under suidperl was somehow illegal.
2460
fe13d51d 2461=item Illegal switch in PERL5OPT: -%c
6ff81951 2462
6df41af2 2463(X) The PERL5OPT environment variable may only be used to set the
646ca9b2 2464following switches: B<-[CDIMUdmtw]>.
6ff81951 2465
6df41af2 2466=item Ill-formed CRTL environ value "%s"
81e118e0 2467
75b44862 2468(W internal) A warning peculiar to VMS. Perl tried to read the CRTL's
be771a83
GS
2469internal environ array, and encountered an element without the C<=>
2470delimiter used to separate keys from values. The element is ignored.
09bef843 2471
6df41af2 2472=item Ill-formed message in prime_env_iter: |%s|
54310121 2473
be771a83
GS
2474(W internal) A warning peculiar to VMS. Perl tried to read a logical
2475name or CLI symbol definition when preparing to iterate over %ENV, and
2476didn't see the expected delimiter between key and value, so the line was
2477ignored.
54310121 2478
6df41af2 2479=item (in cleanup) %s
9607fc9c 2480
be771a83
GS
2481(W misc) This prefix usually indicates that a DESTROY() method raised
2482the indicated exception. Since destructors are usually called by the
2483system at arbitrary points during execution, and often a vast number of
2484times, the warning is issued only once for any number of failures that
2485would otherwise result in the same message being repeated.
6df41af2 2486
be771a83
GS
2487Failure of user callbacks dispatched using the C<G_KEEPERR> flag could
2488also result in this warning. See L<perlcall/G_KEEPERR>.
9607fc9c 2489
e0e4a6e3
FC
2490=item Incomplete expression within '(?[ ])' in regex; marked by S<<-- HERE>
2491in m/%s/
0d0b4b3b 2492
675fa9ff 2493(F) There was a syntax error within the C<(?[ ])>. This can happen if the
0d0b4b3b
KW
2494expression inside the construct was completely empty, or if there are
2495too many or few operands for the number of operators. Perl is not smart
2496enough to give you a more precise indication as to what is wrong.
2497
6fbc9859
MH
2498=item Inconsistent hierarchy during C3 merge of class '%s': merging failed on
2499parent '%s'
2c7d6b9c
RGS
2500
2501(F) The method resolution order (MRO) of the given class is not
2502C3-consistent, and you have enabled the C3 MRO for this class. See the C3
2503documentation in L<mro> for more information.
2504
979699d9
JH
2505=item In EBCDIC the v-string components cannot exceed 2147483647
2506
2507(F) An error peculiar to EBCDIC. Internally, v-strings are stored as
2508Unicode code points, and encoded in EBCDIC as UTF-EBCDIC. The UTF-EBCDIC
2509encoding is limited to code points no larger than 2147483647 (0x7FFFFFFF).
2510
6a2ed79a 2511=item Infinite recursion in regex
1a147d38
YO
2512
2513(F) You used a pattern that references itself without consuming any input
6903afa2 2514text. You should check the pattern to ensure that recursive patterns
1a147d38
YO
2515either consume text or fail.
2516
6dbe9451
NC
2517=item Initialization of state variables in list context currently forbidden
2518
6903afa2
FC
2519(F) Currently the implementation of "state" only permits the
2520initialization of scalar variables in scalar context. Re-write
2521C<state ($a) = 42> as C<state $a = 42> to change from list to scalar
2522context. Constructions such as C<state (@a) = foo()> will be
2523supported in a future perl release.
6dbe9451 2524
2186f873
FC
2525=item %%s[%s] in scalar context better written as $%s[%s]
2526
2527(W syntax) In scalar context, you've used an array index/value slice
2528(indicated by %) to select a single element of an array. Generally
2529it's better to ask for a scalar value (indicated by $). The difference
2530is that C<$foo[&bar]> always behaves like a scalar, both in the value it
2531returns and when evaluating its argument, while C<%foo[&bar]> provides
2532a list context to its subscript, which can do weird things if you're
2533expecting only one subscript. When called in list context, it also
2534returns the index (what C<&bar> returns) in addition to the value.
2535
2536=item %%s{%s} in scalar context better written as $%s{%s}
2537
2538(W syntax) In scalar context, you've used a hash key/value slice
2539(indicated by %) to select a single element of a hash. Generally it's
2540better to ask for a scalar value (indicated by $). The difference
2541is that C<$foo{&bar}> always behaves like a scalar, both in the value
2542it returns and when evaluating its argument, while C<@foo{&bar}> and
2543provides a list context to its subscript, which can do weird things
2544if you're expecting only one subscript. When called in list context,
2545it also returns the key in addition to the value.
2546
a0d0e21e
LW
2547=item Insecure dependency in %s
2548
8b1a09fc 2549(F) You tried to do something that the tainting mechanism didn't like.
be771a83
GS
2550The tainting mechanism is turned on when you're running setuid or
2551setgid, or when you specify B<-T> to turn it on explicitly. The
2552tainting mechanism labels all data that's derived directly or indirectly
2553from the user, who is considered to be unworthy of your trust. If any
2554such data is used in a "dangerous" operation, you get this error. See
2555L<perlsec> for more information.
a0d0e21e
LW
2556
2557=item Insecure directory in %s
2558
be771a83
GS
2559(F) You can't use system(), exec(), or a piped open in a setuid or
2560setgid script if C<$ENV{PATH}> contains a directory that is writable by
df98f984
RGS
2561the world. Also, the PATH must not contain any relative directory.
2562See L<perlsec>.
a0d0e21e 2563
62f468fc 2564=item Insecure $ENV{%s} while running %s
a0d0e21e
LW
2565
2566(F) You can't use system(), exec(), or a piped open in a setuid or
62f468fc 2567setgid script if any of C<$ENV{PATH}>, C<$ENV{IFS}>, C<$ENV{CDPATH}>,
332d5f78
SR
2568C<$ENV{ENV}>, C<$ENV{BASH_ENV}> or C<$ENV{TERM}> are derived from data
2569supplied (or potentially supplied) by the user. The script must set
2570the path to a known value, using trustworthy data. See L<perlsec>.
a0d0e21e 2571
0e9be77f
DM
2572=item Insecure user-defined property %s
2573
2574(F) Perl detected tainted data when trying to compile a regular
2575expression that contains a call to a user-defined character property
2576function, i.e. C<\p{IsFoo}> or C<\p{InFoo}>.
2577See L<perlunicode/User-Defined Character Properties> and L<perlsec>.
2578
b9ef414d
FC
2579=item Integer overflow in format string for %s
2580
2581(F) The indexes and widths specified in the format string of C<printf()>
2582or C<sprintf()> are too large. The numbers must not overflow the size of
2583integers for your architecture.
2584
a7ae9550
GS
2585=item Integer overflow in %s number
2586
35928bc5 2587(S overflow) The hexadecimal, octal or binary number you have specified
be771a83
GS
2588either as a literal or as an argument to hex() or oct() is too big for
2589your architecture, and has been converted to a floating point number.
2590On a 32-bit architecture the largest hexadecimal, octal or binary number
9e24b6e2
JH
2591representable without overflow is 0xFFFFFFFF, 037777777777, or
25920b11111111111111111111111111111111 respectively. Note that Perl
2593transparently promotes all numbers to a floating point representation
2594internally--subject to loss of precision errors in subsequent
2595operations.
bbce6d69 2596
fc89ca81
FC
2597=item Integer overflow in srand
2598
2599(S overflow) The number you have passed to srand is too big to fit
2600in your architecture's integer representation. The number has been
2601replaced with the largest integer supported (0xFFFFFFFF on 32-bit
2602architectures). This means you may be getting less randomness than
2603you expect, because different random seeds above the maximum will
2604return the same sequence of random numbers.
2605
46314c13
JP
2606=item Integer overflow in version
2607
18da5252
FC
2608=item Integer overflow in version %d
2609
784d71ed
FC
2610(W overflow) Some portion of a version initialization is too large for
2611the size of integers for your architecture. This is not a warning
f084e84f 2612because there is no rational reason for a version to try and use an
784d71ed
FC
2613element larger than typically 2**32. This is usually caused by trying
2614to use some odd mathematical operation as a version, like 100/9.
46314c13 2615
e0e4a6e3 2616=item Internal disaster in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2617
2618(P) Something went badly wrong in the regular expression parser.
e0e4a6e3 2619The S<<-- HERE> shows whereabouts in the regular expression the problem was
b45f050a
JF
2620discovered.
2621
748a9306
LW
2622=item Internal inconsistency in tracking vforks
2623
be771a83
GS
2624(S) A warning peculiar to VMS. Perl keeps track of the number of times
2625you've called C<fork> and C<exec>, to determine whether the current call
2626to C<exec> should affect the current script or a subprocess (see
2627L<perlvms/"exec LIST">). Somehow, this count has become scrambled, so
2628Perl is making a guess and treating this C<exec> as a request to
2629terminate the Perl script and execute the specified command.
748a9306 2630
870978ae
FC
2631=item internal %<num>p might conflict with future printf extensions
2632
2633(S internal) Perl's internal routine that handles C<printf> and C<sprintf>
2634formatting follows a slightly different set of rules when called from
2635C or XS code. Specifically, formats consisting of digits followed
2636by "p" (e.g., "%7p") are reserved for future use. If you see this
2637message, then an XS module tried to call that routine with one such
2638reserved format.
2639
e0e4a6e3 2640=item Internal urp in regex; marked by S<<-- HERE> in m/%s/
b45f050a 2641
fa816bf3 2642(P) Something went badly awry in the regular expression parser. The
e0e4a6e3 2643S<<-- HERE> shows whereabouts in the regular expression the problem was
7253e4e3 2644discovered.
a0d0e21e 2645
6df41af2
GS
2646=item %s (...) interpreted as function
2647
75b44862 2648(W syntax) You've run afoul of the rule that says that any list operator
be771a83 2649followed by parentheses turns into a function, with all the list
64977eb6 2650operators arguments found inside the parentheses. See
13a2d996 2651L<perlop/Terms and List Operators (Leftward)>.
6df41af2 2652
f51551f7
FC
2653=item In '(?...)', the '(' and '?' must be adjacent in regex;
2654marked by S<<-- HERE> in m/%s/
2655
2656(F) The two-character sequence C<"(?"> in this context in a regular
2657expression pattern should be an indivisible token, with nothing
2658intervening between the C<"("> and the C<"?">, but you separated them
2659with whitespace.
2660
09bef843
SB
2661=item Invalid %s attribute: %s
2662
a4a4c9e2 2663(F) The indicated attribute for a subroutine or variable was not recognized
09bef843
SB
2664by Perl or by a user-supplied handler. See L<attributes>.
2665
2666=item Invalid %s attributes: %s
2667
a4a4c9e2 2668(F) The indicated attributes for a subroutine or variable were not
be771a83 2669recognized by Perl or by a user-supplied handler. See L<attributes>.
09bef843 2670
e0e4a6e3
FC
2671=item Invalid character in charnames alias definition; marked by
2672S<<-- HERE> in '%s
225fb84f
KW
2673
2674(F) You tried to create a custom alias for a character name, with
2675the C<:alias> option to C<use charnames> and the specified character in
2676the indicated name isn't valid. See L<charnames/CUSTOM ALIASES>.
2677
c8028aa6
TC
2678=item Invalid \0 character in %s for %s: %s\0%s
2679
fa3234e3
FC
2680(W syscalls) Embedded \0 characters in pathnames or other system call
2681arguments produce a warning as of 5.20. The parts after the \0 were
2682formerly ignored by system calls.
c8028aa6 2683
e0e4a6e3 2684=item Invalid character in \N{...}; marked by S<<-- HERE> in \N{%s}
a690c7c4
FC
2685
2686(F) Only certain characters are valid for character names. The
2687indicated one isn't. See L<charnames/CUSTOM ALIASES>.
2688
c635e13b
PP
2689=item Invalid conversion in %s: "%s"
2690
be771a83
GS
2691(W printf) Perl does not understand the given format conversion. See
2692L<perlfunc/sprintf>.
c635e13b 2693
e0e4a6e3
FC
2694=item Invalid escape in the specified encoding in regex; marked by
2695S<<-- HERE> in m/%s/
9e08bc66 2696
98d31c73 2697(W regexp)(F) The numeric escape (for example C<\xHH>) of value < 256
9e08bc66
ST
2698didn't correspond to a single character through the conversion
2699from the encoding specified by the encoding pragma.
98d31c73
FC
2700The escape was replaced with REPLACEMENT CHARACTER (U+FFFD)
2701instead, except within S<C<(?[ ])>>, where it is a fatal error.
e0e4a6e3 2702The S<<-- HERE> shows whereabouts in the regular expression the
9e08bc66
ST
2703escape was discovered.
2704
af5e7be2
FC
2705=item %s: Invalid handshake key got %p needed %p, binaries are mismatched
2706
2707(P) A dynamic loading library C<.so> or C<.dll> was being loaded into the
2708process that was built against a different build of perl than the
2709said library was compiled against. Reinstalling the XS module will
2710likely fix this error.
2711
8149aa9f
FC
2712=item Invalid hexadecimal number in \N{U+...}
2713
e0e4a6e3
FC
2714=item Invalid hexadecimal number in \N{U+...} in regex; marked by
2715S<<-- HERE> in m/%s/
aec0ef10 2716
8149aa9f 2717(F) The character constant represented by C<...> is not a valid hexadecimal
74f8e9e3
FC
2718number. Either it is empty, or you tried to use a character other than
27190 - 9 or A - F, a - f in a hexadecimal number.
8149aa9f 2720
6651ba0b
FC
2721=item Invalid module name %s with -%c option: contains single ':'
2722
2723(F) The module argument to perl's B<-m> and B<-M> command-line options
2724cannot contain single colons in the module name, but only in the
2725arguments after "=". In other words, B<-MFoo::Bar=:baz> is ok, but
2726B<-MFoo:Bar=baz> is not.
2727
2c7d6b9c
RGS
2728=item Invalid mro name: '%s'
2729
162a3e34
FC
2730(F) You tried to C<mro::set_mro("classname", "foo")> or C<use mro 'foo'>,
2731where C<foo> is not a valid method resolution order (MRO). Currently,
2732the only valid ones supported are C<dfs> and C<c3>, unless you have loaded
2733a module that is a MRO plugin. See L<mro> and L<perlmroapi>.
2c7d6b9c 2734
40e4140b
FC
2735=item Invalid negative number (%s) in chr
2736
2737(W utf8) You passed a negative number to C<chr>. Negative numbers are
abc0aa9d 2738not valid character numbers, so it returns the Unicode replacement
40e4140b
FC
2739character (U+FFFD).
2740
6651ba0b
FC
2741=item invalid option -D%c, use -D'' to see choices
2742
8ff21bfe
FC
2743(S debugging) Perl was called with invalid debugger flags. Call perl
2744with the B<-D> option with no flags to see the list of acceptable values.
982c4ecb 2745See also L<perlrun/-Dletters>.
6651ba0b 2746
e0e4a6e3 2747=item Invalid [] range "%s" in regex; marked by S<<-- HERE> in m/%s/
6df41af2
GS
2748
2749(F) The range specified in a character class had a minimum character
7253e4e3
RK
2750greater than the maximum character. One possibility is that you forgot the
2751C<{}> from your ending C<\x{}> - C<\x> without the curly braces can go only
e0e4a6e3 2752up to C<ff>. The S<<-- HERE> shows whereabouts in the regular expression the
7253e4e3 2753problem was discovered. See L<perlre>.
6df41af2 2754
d1573ac7 2755=item Invalid range "%s" in transliteration operator
c2e66d9e
GS
2756
2757(F) The range specified in the tr/// or y/// operator had a minimum
2758character greater than the maximum character. See L<perlop>.
2759
09bef843
SB
2760=item Invalid separator character %s in attribute list
2761
0120eecf 2762(F) Something other than a colon or whitespace was seen between the
be771a83
GS
2763elements of an attribute list. If the previous attribute had a
2764parenthesised parameter list, perhaps that list was terminated too soon.
2765See L<attributes>.
09bef843 2766
b4581f09
JH
2767=item Invalid separator character %s in PerlIO layer specification %s
2768
2bfc5f71
FC
2769(W layer) When pushing layers onto the Perl I/O system, something other
2770than a colon or whitespace was seen between the elements of a layer list.
b4581f09
JH
2771If the previous attribute had a parenthesised parameter list, perhaps that
2772list was terminated too soon.
2773
2c86d456
DG
2774=item Invalid strict version format (%s)
2775
fa816bf3 2776(F) A version number did not meet the "strict" criteria for versions.
2c86d456
DG
2777A "strict" version number is a positive decimal number (integer or
2778decimal-fraction) without exponentiation or else a dotted-decimal
2779v-string with a leading 'v' character and at least three components.
a6485a24 2780The parenthesized text indicates which criteria were not met.
2c86d456
DG
2781See the L<version> module for more details on allowed version formats.
2782
49704364 2783=item Invalid type '%s' in %s
96e4d5b1 2784
49704364
LW
2785(F) The given character is not a valid pack or unpack type.
2786See L<perlfunc/pack>.
6728c851 2787
49704364 2788(W) The given character is not a valid pack or unpack type but used to be
75b44862 2789silently ignored.
96e4d5b1 2790
2c86d456
DG
2791=item Invalid version format (%s)
2792
fa816bf3 2793(F) A version number did not meet the "lax" criteria for versions.
2c86d456
DG
2794A "lax" version number is a positive decimal number (integer or
2795decimal-fraction) without exponentiation or else a dotted-decimal
fa816bf3
FC
2796v-string. If the v-string has fewer than three components, it
2797must have a leading 'v' character. Otherwise, the leading 'v' is
2798optional. Both decimal and dotted-decimal versions may have a
2799trailing "alpha" component separated by an underscore character
2800after a fractional or dotted-decimal component. The parenthesized
2801text indicates which criteria were not met. See the L<version> module
2802for more details on allowed version formats.
46314c13 2803
798ae1b7
DG
2804=item Invalid version object
2805
fa816bf3
FC
2806(F) The internal structure of the version object was invalid.
2807Perhaps the internals were modified directly in some way or
2808an arbitrary reference was blessed into the "version" class.
798ae1b7 2809
cd209d9d 2810=item In '(*VERB...)', the '(' and '*' must be adjacent in regex;
e0e4a6e3 2811marked by S<<-- HERE> in m/%s/
675fa9ff 2812
cd209d9d 2813(F) The two-character sequence C<"(*"> in
675fa9ff
FC
2814this context in a regular expression pattern should be an
2815indivisible token, with nothing intervening between the C<"(">
cd209d9d 2816and the C<"*">, but you separated them.
675fa9ff 2817
a0d0e21e
LW
2818=item ioctl is not implemented
2819
2820(F) Your machine apparently doesn't implement ioctl(), which is pretty
2821strange for a machine that supports C.
2822
c289d2f7
JH
2823=item ioctl() on unopened %s
2824
2825(W unopened) You tried ioctl() on a filehandle that was never opened.
34b6fd5e 2826Check your control flow and number of arguments.
c289d2f7 2827
fe13d51d 2828=item IO layers (like '%s') unavailable
363c40c4
SB
2829
2830(F) Your Perl has not been configured to have PerlIO, and therefore
34b6fd5e 2831you cannot use IO layers. To have PerlIO, Perl must be configured
363c40c4
SB
2832with 'useperlio'.
2833
80cbd5ad
JH
2834=item IO::Socket::atmark not implemented on this architecture
2835
2836(F) Your machine doesn't implement the sockatmark() functionality,
34b6fd5e 2837neither as a system call nor an ioctl call (SIOCATMARK).
80cbd5ad 2838
4f650b80 2839=item $* is no longer supported
b4581f09 2840
4f650b80 2841(D deprecated, syntax) The special variable C<$*>, deprecated in older
ea9d9ebc 2842perls, has been removed as of 5.10.0 and is no longer supported. In
4f650b80
NC
2843previous versions of perl the use of C<$*> enabled or disabled multi-line
2844matching within a string.
4fd19576
B
2845
2846Instead of using C<$*> you should use the C</m> (and maybe C</s>) regexp
6903afa2
FC
2847modifiers. You can enable C</m> for a lexical scope (even a whole file)
2848with C<use re '/m'>. (In older versions: when C<$*> was set to a true value
570dedd4 2849then all regular expressions behaved as if they were written using C</m>.)
b4581f09 2850
8ae1fe26
RGS
2851=item $# is no longer supported
2852
a58ac25e 2853(D deprecated, syntax) The special variable C<$#>, deprecated in older
ea9d9ebc 2854perls, has been removed as of 5.10.0 and is no longer supported. You
a58ac25e 2855should use the printf/sprintf functions instead.
8ae1fe26 2856
ccf3535a 2857=item '%s' is not a code reference
6ad11d81 2858
6903afa2
FC
2859(W overload) The second (fourth, sixth, ...) argument of
2860overload::constant needs to be a code reference. Either
2861an anonymous subroutine, or a reference to a subroutine.
6ad11d81 2862
ccf3535a 2863=item '%s' is not an overloadable type
6ad11d81 2864
04a80ee0
RGS
2865(W overload) You tried to overload a constant type the overload package is
2866unaware of.
6ad11d81 2867
5a25739d
FC
2868=item -i used with no filenames on the command line, reading from STDIN
2869
2870(S inplace) The C<-i> option was passed on the command line, indicating
2871that the script is intended to edit files in place, but no files were
2872given. This is usually a mistake, since editing STDIN in place doesn't
2873make sense, and can be confusing because it can make perl look like
2874it is hanging when it is really just trying to read from STDIN. You
2875should either pass a filename to edit, or remove C<-i> from the command
2876line. See L<perlrun> for more details.
2877
aec0ef10 2878=item Junk on end of regexp in regex m/%s/
a0d0e21e
LW
2879
2880(P) The regular expression parser is confused.
2881
0953b66b
FC
2882=item keys on reference is experimental
2883
0773cb3e
FC
2884(S experimental::autoderef) C<keys> with a scalar argument is experimental
2885and may change or be removed in a future Perl version. If you want to
2886take the risk of using this feature, simply disable this warning:
0953b66b 2887
d401967c 2888 no warnings "experimental::autoderef";
0953b66b 2889
a0d0e21e
LW
2890=item Label not found for "last %s"
2891
be771a83
GS
2892(F) You named a loop to break out of, but you're not currently in a loop
2893of that name, not even if you count where you were called from. See
2894L<perlfunc/last>.
a0d0e21e
LW
2895
2896=item Label not found for "next %s"
2897
2898(F) You named a loop to continue, but you're not currently in a loop of
2899that name, not even if you count where you were called from. See
2900L<perlfunc/last>.
2901
2902=item Label not found for "redo %s"
2903
2904(F) You named a loop to restart, but you're not currently in a loop of
2905that name, not even if you count where you were called from. See
2906L<perlfunc/last>.
2907
85ab1d1d 2908=item leaving effective %s failed
5ff3f7a4 2909
85ab1d1d 2910(F) While under the C<use filetest> pragma, switching the real and
5ff3f7a4
GS
2911effective uids or gids failed.
2912
49704364
LW
2913=item length/code after end of string in unpack
2914
d7f8936a 2915(F) While unpacking, the string buffer was already used up when an unpack
6903afa2
FC
2916length/code combination tried to obtain more data. This results in
2917an undefined value for the length. See L<perlfunc/pack>.
49704364 2918
25e26107 2919=item length() used on %s (did you mean "scalar(%s)"?)
e508c8a4 2920
0d46a4e7
FC
2921(W syntax) You used length() on either an array or a hash when you
2922probably wanted a count of the items.
e508c8a4
MH
2923
2924Array size can be obtained by doing:
2925
2926 scalar(@array);
2927
2928The number of items in a hash can be obtained by doing:
2929
2930 scalar(keys %hash);
2931
f0e67a1d
Z
2932=item Lexing code attempted to stuff non-Latin-1 character into Latin-1 input
2933
d4fe7078
RS
2934(F) An extension is attempting to insert text into the current parse
2935(using L<lex_stuff_pvn|perlapi/lex_stuff_pvn> or similar), but tried to insert a character that
2936couldn't be part of the current input. This is an inherent pitfall
2937of the stuffing mechanism, and one of the reasons to avoid it. Where
6903afa2 2938it is necessary to stuff, stuffing only plain ASCII is recommended.
f0e67a1d
Z
2939
2940=item Lexing code internal error (%s)
2941
2942(F) Lexing code supplied by an extension violated the lexer's API in a
2943detectable way.
2944
69282e91 2945=item listen() on closed socket %s
a0d0e21e 2946
be771a83
GS
2947(W closed) You tried to do a listen on a closed socket. Did you forget
2948to check the return value of your socket() call? See
2949L<perlfunc/listen>.
a0d0e21e 2950
6651ba0b
FC
2951=item List form of piped open not implemented
2952
2953(F) On some platforms, notably Windows, the three-or-more-arguments
2954form of C<open> does not support pipes, such as C<open($pipe, '|-', @args)>.
2955Use the two-argument C<open($pipe, '|prog arg1 arg2...')> form instead.
2956
b35b96b6
JH
2957=item localtime(%f) failed
2958
2959(W overflow) You called C<localtime> with a number that it could not handle:
2960too large, too small, or NaN. The returned value is C<undef>.
2961
bcd05b94 2962=item localtime(%f) too large
8b56d6ff 2963
e9200be3 2964(W overflow) You called C<localtime> with a number that was larger
fc003d4b 2965than it can reliably handle and C<localtime> probably returned the
6903afa2 2966wrong date. This warning is also triggered with NaN (the special
fc003d4b
MS
2967not-a-number value).
2968
bcd05b94 2969=item localtime(%f) too small
fc003d4b 2970
e9200be3 2971(W overflow) You called C<localtime> with a number that was smaller
fc003d4b 2972than it can reliably handle and C<localtime> probably returned the
e7a1a147 2973wrong date.
8b56d6ff 2974
58e23c8d 2975=item Lookbehind longer than %d not implemented in regex m/%s/
b45f050a
JF
2976
2977(F) There is currently a limit on the length of string which lookbehind can
6903afa2 2978handle. This restriction may be eased in a future release.
2e50fd82 2979
b88df990
NC
2980=item Lost precision when %s %f by 1
2981
e63e8a91
FC
2982(W imprecision) The value you attempted to increment or decrement by one
2983is too large for the underlying floating point representation to store
2984accurately, hence the target of C<++> or C<--> is unchanged. Perl issues this
2985warning because it has already switched from integers to floating point
2986when values are too large for integers, and now even floating point is
2987insufficient. You may wish to switch to using L<Math::BigInt> explicitly.
b88df990 2988
93fad930 2989=item lstat() on filehandle%s
2f7da168
RK
2990
2991(W io) You tried to do an lstat on a filehandle. What did you mean
2992by that? lstat() makes sense only on filenames. (Perl did a fstat()
2993instead on the filehandle.)
2994
345d70e3 2995=item lvalue attribute %s already-defined subroutine
bb3abb05 2996
345d70e3
FC
2997(W misc) Although L<attributes.pm|attributes> allows this, turning the lvalue
2998attribute on or off on a Perl subroutine that is already defined
2999does not always work properly. It may or may not do what you
3000want, depending on what code is inside the subroutine, with exact
3001details subject to change between Perl versions. Only do this
3002if you really know what you are doing.
bb3abb05 3003
885ef6f5
GG
3004=item lvalue attribute ignored after the subroutine has been defined
3005
345d70e3
FC
3006(W misc) Using the C<:lvalue> declarative syntax to make a Perl
3007subroutine an lvalue subroutine after it has been defined is
3008not permitted. To make the subroutine an lvalue subroutine,
3009add the lvalue attribute to the definition, or put the C<sub
3010foo :lvalue;> declaration before the definition.
3011
3012See also L<attributes.pm|attributes>.
885ef6f5 3013
6f1b3ab0
FC
3014=item Magical list constants are not supported
3015
3016(F) You assigned a magical array to a stash element, and then tried
3017to use the subroutine from the same slot. You are asking Perl to do
3018something it cannot do, details subject to change between Perl versions.
3019
2db62bbc 3020=item Malformed integer in [] in pack
49704364 3021
2db62bbc 3022(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3023are permitted. See L<perlfunc/pack>.
3024
3025=item Malformed integer in [] in unpack
3026
2db62bbc 3027(F) Between the brackets enclosing a numeric repeat count only digits
49704364
LW
3028are permitted. See L<perlfunc/pack>.
3029
6df41af2
GS
3030=item Malformed PERLLIB_PREFIX
3031
3032(F) An error peculiar to OS/2. PERLLIB_PREFIX should be of the form
3033
3034 prefix1;prefix2
3035
3036or
6df41af2
GS
3037 prefix1 prefix2
3038
be771a83
GS
3039with nonempty prefix1 and prefix2. If C<prefix1> is indeed a prefix of
3040a builtin library search path, prefix2 is substituted. The error may
3041appear if components are not found, or are too long. See
fecfaeb8 3042"PERLLIB_PREFIX" in L<perlos2>.
6df41af2 3043
2f758a16
ST
3044=item Malformed prototype for %s: %s
3045
d37a9538
ST
3046(F) You tried to use a function with a malformed prototype. The
3047syntax of function prototypes is given a brief compile-time check for
3048obvious errors like invalid characters. A more rigorous check is run
3049when the function is called.
30d9c59b
Z
3050Perhaps the function's author was trying to write a subroutine signature
3051but didn't enable that feature first (C<use feature 'signatures'>),
3052so the signature was instead interpreted as a bad prototype.
2f758a16 3053
ba210ebe
JH
3054=item Malformed UTF-8 character (%s)
3055
4d6f11e5 3056(S utf8)(F) Perl detected a string that didn't comply with UTF-8
2575c402 3057encoding rules, even though it had the UTF8 flag on.
ba210ebe 3058
2575c402
JW
3059One possible cause is that you set the UTF8 flag yourself for data that
3060you thought to be in UTF-8 but it wasn't (it was for example legacy
6903afa2 30618-bit data). To guard against this, you can use Encode::decode_utf8.
2575c402
JW
3062
3063If you use the C<:encoding(UTF-8)> PerlIO layer for input, invalid byte
3064sequences are handled gracefully, but if you use C<:utf8>, the flag is
3065set without validating the data, possibly resulting in this error
3066message.
3067
3068See also L<Encode/"Handling Malformed Data">.
901b21bf 3069
107160e2
KW
3070=item Malformed UTF-8 character immediately after '%s'
3071
3072(F) You said C<use utf8>, but the program file doesn't comply with UTF-8
3073encoding rules. The message prints out the properly encoded characters
3074just before the first bad one. If C<utf8> warnings are enabled, a
3075warning is generated that gives more details about the type of
3076malformation.
3077
bde9e88d 3078=item Malformed UTF-8 returned by \N{%s} immediately after '%s'
ff3f963a
KW
3079
3080(F) The charnames handler returned malformed UTF-8.
3081
4a5d3a93
FC
3082=item Malformed UTF-8 string in '%c' format in unpack
3083
3084(F) You tried to unpack something that didn't comply with UTF-8 encoding
3085rules and perl was unable to guess how to make more progress.
3086
f337b084
TH
3087=item Malformed UTF-8 string in pack
3088
3089(F) You tried to pack something that didn't comply with UTF-8 encoding
3090rules and perl was unable to guess how to make more progress.
3091
3092=item Malformed UTF-8 string in unpack
3093
3094(F) You tried to unpack something that didn't comply with UTF-8 encoding
3095rules and perl was unable to guess how to make more progress.
3096
4a5d3a93 3097=item Malformed UTF-16 surrogate
f337b084 3098
4a5d3a93
FC
3099(F) Perl thought it was reading UTF-16 encoded character data but while
3100doing it Perl met a malformed Unicode surrogate.
3101
30d9c59b
Z
3102=item Mandatory parameter follows optional parameter
3103
3104(F) In a subroutine signature, you wrote something like "$a = undef,
3105$b", making an earlier parameter optional and a later one mandatory.
3106Parameters are filled from left to right, so it's impossible for the
3107caller to omit an earlier one and pass a later one. If you want to act
3108as if the parameters are filled from right to left, declare the rightmost
3109optional and then shuffle the parameters around in the subroutine's body.
3110
2d88a86a
KW
3111=item Matched non-Unicode code point 0x%X against Unicode property; may
3112not be portable
3113
3114(S non_unicode) Perl allows strings to contain a superset of
3115Unicode code points; each code point may be as large as what is storable
3116in an unsigned integer on your system, but these may not be accepted by
3117other languages/systems. This message occurs when you matched a string
3118containing such a code point against a regular expression pattern, and
3119the code point was matched against a Unicode property, C<\p{...}> or
3120C<\P{...}>. Unicode properties are only defined on Unicode code points,
3121so the result of this match is undefined by Unicode, but Perl (starting
3122in v5.20) treats non-Unicode code points as if they were typical
3123unassigned Unicode ones, and matched this one accordingly. Whether a
3124given property matches these code points or not is specified in
3125L<perluniprops/Properties accessible through \p{} and \P{}>.
3126
3127This message is suppressed (unless it has been made fatal) if it is
3128immaterial to the results of the match if the code point is Unicode or
3129not. For example, the property C<\p{ASCII_Hex_Digit}> only can match
3130the 22 characters C<[0-9A-Fa-f]>, so obviously all other code points,
3131Unicode or not, won't match it. (And C<\P{ASCII_Hex_Digit}> will match
3132every code point except these 22.)
3133
3134Getting this message indicates that the outcome of the match arguably
3135should have been the opposite of what actually happened. If you think
3136that is the case, you may wish to make the C<non_unicode> warnings
3137category fatal; if you agree with Perl's decision, you may wish to turn
3138off this category.
3139
3140See L<perlunicode/Beyond Unicode code points> for more information.
3141
e0e4a6e3
FC
3142=item %s matches null string many times in regex; marked by S<<-- HERE> in
3143m/%s/
4a5d3a93
FC
3144
3145(W regexp) The pattern you've specified would be an infinite loop if the
e0e4a6e3 3146regular expression engine didn't specifically check for that. The S<<-- HERE>
9e3ec65c 3147shows whereabouts in the regular expression the problem was discovered.
4a5d3a93 3148See L<perlre>.
f337b084 3149
de42a5a9 3150=item Maximal count of pending signals (%u) exceeded
2563cec5 3151
6903afa2 3152(F) Perl aborted due to too high a number of signals pending. This
2563cec5
IZ
3153usually indicates that your operating system tried to deliver signals
3154too fast (with a very high priority), starving the perl process from
3155resources it would need to reach a point where it can process signals
6903afa2 3156safely. (See L<perlipc/"Deferred Signals (Safe Signals)">.)
2563cec5 3157
25f58aea
PN
3158=item "%s" may clash with future reserved word
3159
3160(W) This warning may be due to running a perl5 script through a perl4
3161interpreter, especially if the word that is being warned about is
3162"use" or "my".
3163
0d2487cd 3164=item '%' may not be used in pack
6df41af2
GS
3165
3166(F) You can't pack a string by supplying a checksum, because the
be771a83
GS
3167checksumming process loses information, and you can't go the other way.
3168See L<perlfunc/unpack>.
6df41af2 3169
a0d0e21e
LW
3170=item Method for operation %s not found in package %s during blessing
3171
3172(F) An attempt was made to specify an entry in an overloading table that
e7ea3e70 3173doesn't resolve to a valid subroutine. See L<overload>.
a0d0e21e 3174
3cdd684c
TP
3175=item Method %s not permitted
3176
3177See Server error.
3178
a0d0e21e
LW
3179=item Might be a runaway multi-line %s string starting on line %d
3180
3181(S) An advisory indicating that the previous error may have been caused
3182by a missing delimiter on a string or pattern, because it eventually
3183ended earlier on the current line.
3184
3185=item Misplaced _ in number
3186
d4ced10d
JH
3187(W syntax) An underscore (underbar) in a numeric constant did not
3188separate two digits.
a0d0e21e 3189
7baa4690
HS
3190=item Missing argument in %s
3191
3664866e
AB
3192(W missing) You called a function with fewer arguments than other
3193arguments you supplied indicated would be needed.
3194
3195Currently only emitted when a printf-type format required more
3196arguments than were supplied, but might be used in the future for
3197other cases where we can statically determine that arguments to
3198functions are missing, e.g. for the L<perlfunc/pack> function.
7baa4690 3199
9e81e6a1
RGS
3200=item Missing argument to -%c
3201
3202(F) The argument to the indicated command line switch must follow
3203immediately after the switch, without intervening spaces.
3204
ff3f963a 3205=item Missing braces on \N{}
423cee85 3206
e0e4a6e3 3207=item Missing braces on \N{} in regex; marked by S<<-- HERE> in m/%s/
aec0ef10 3208
4a2d328f 3209(F) Wrong syntax of character name literal C<\N{charname}> within
532cb70d
FC
3210double-quotish context. This can also happen when there is a space
3211(or comment) between the C<\N> and the C<{> in a regex with the C</x> modifier.
3212This modifier does not change the requirement that the brace immediately
3213follow the C<\N>.
423cee85 3214
f0a2b745
KW
3215=item Missing braces on \o{}
3216
3217(F) A C<\o> must be followed immediately by a C<{> in double-quotish context.
3218
a0d0e21e
LW
3219=item Missing comma after first argument to %s function
3220
3221(F) While certain functions allow you to specify a filehandle or an
3222"indirect object" before the argument list, this ain't one of them.
3223
06eaf0bc
GS
3224=item Missing command in piped open
3225
be771a83
GS
3226(W pipe) You used the C<open(FH, "| command")> or
3227C<open(FH, "command |")> construction, but the command was missing or
3228blank.
06eaf0bc 3229
961ce445
RGS
3230=item Missing control char name in \c
3231
3232(F) A double-quoted string ended with "\c", without the required control
3233character name.
3234
591f5ca2
FC
3235=item Missing ']' in prototype for %s : %s
3236
bfe11873 3237(W illegalproto) A grouping was started with C<[> but never closed with C<]>.
591f5ca2 3238
8767b1ab 3239=item Missing name in "%s sub"
6df41af2 3240
87444db5 3241(F) The syntax for lexically scoped subroutines requires that
be771a83 3242they have a name with which they can be found.
6df41af2
GS
3243
3244=item Missing $ on loop variable
3245
be771a83
GS
3246(F) Apparently you've been programming in B<csh> too much. Variables
3247are always mentioned with the $ in Perl, unlike in the shells, where it
3248can vary from one line to the next.
6df41af2 3249
cc507455 3250=item (Missing operator before %s?)
748a9306 3251
56da5a46
RGS
3252(S syntax) This is an educated guess made in conjunction with the message
3253"%s found where operator expected". Often the missing operator is a comma.
748a9306 3254
f51551f7
FC
3255=item Missing or undefined argument to require
3256
3257(F) You tried to call require with no argument or with an undefined
3258value as an argument. Require expects either a package name or a
3259file-specification as an argument. See L<perlfunc/require>.
3260
e0e4a6e3 3261=item Missing right brace on \%c{} in regex; marked by S<<-- HERE> in m/%s/
ab13f0c7 3262
ff3f963a
KW
3263(F) Missing right brace in C<\x{...}>, C<\p{...}>, C<\P{...}>, or C<\N{...}>.
3264
4a68bf9d 3265=item Missing right brace on \N{} or unescaped left brace after \N
ff3f963a 3266
d32207c9
FC
3267(F) C<\N> has two meanings.
3268
3269The traditional one has it followed by a name enclosed in braces,
3270meaning the character (or sequence of characters) given by that
fa816bf3 3271name. Thus C<\N{ASTERISK}> is another way of writing C<*>, valid in both
d32207c9
FC
3272double-quoted strings and regular expression patterns. In patterns,
3273it doesn't have the meaning an unescaped C<*> does.
3274
3275Starting in Perl 5.12.0, C<\N> also can have an additional meaning (only)
3276in patterns, namely to match a non-newline character. (This is short
3277for C<[^\n]>, and like C<.> but is not affected by the C</s> regex modifier.)
3278
3279This can lead to some ambiguities. When C<\N> is not followed immediately
3280by a left brace, Perl assumes the C<[^\n]> meaning. Also, if the braces
3281form a valid quantifier such as C<\N{3}> or C<\N{5,}>, Perl assumes that this
3282means to match the given quantity of non-newlines (in these examples,
32833; and 5 or more, respectively). In all other case, where there is a
3284C<\N{> and a matching C<}>, Perl assumes that a character name is desired.
3285
3286However, if there is no matching C<}>, Perl doesn't know if it was
3287mistakenly omitted, or if C<[^\n]{> was desired, and raises this error.
3288If you meant the former, add the right brace; if you meant the latter,
3289escape the brace with a backslash, like so: C<\N\{>
ab13f0c7 3290
d98d5fff 3291=item Missing right curly or square bracket
a0d0e21e 3292
be771a83
GS
3293(F) The lexer counted more opening curly or square brackets than closing
3294ones. As a general rule, you'll find it's missing near the place you
3295were last editing.
a0d0e21e 3296
6df41af2
GS
3297=item (Missing semicolon on previous line?)
3298
56da5a46
RGS
3299(S syntax) This is an educated guess made in conjunction with the message
3300"%s found where operator expected". Don't automatically put a semicolon on
6df41af2
GS
3301the previous line just because you saw this message.
3302
a0d0e21e
LW
3303=item Modification of a read-only value attempted
3304
3305(F) You tried, directly or indirectly, to change the value of a
5f05dabc 3306constant. You didn't, of course, try "2 = 1", because the compiler
a0d0e21e
LW
3307catches that. But an easy way to do the same thing is:
3308
3309 sub mod { $_[0] = 1 }
3310 mod(2);
3311
3312Another way is to assign to a substr() that's off the end of the string.
3313
c5674021
PDF
3314Yet another way is to assign to a C<foreach> loop I<VAR> when I<VAR>
3315is aliased to a constant in the look I<LIST>:
3316
b7e4ecc1
FC
3317 $x = 1;
3318 foreach my $n ($x, 2) {
3319 $n *= 2; # modifies the $x, but fails on attempt to
3320 } # modify the 2
c5674021 3321
7a4340ed 3322=item Modification of non-creatable array value attempted, %s
a0d0e21e
LW
3323
3324(F) You tried to make an array value spring into existence, and the
3325subscript was probably negative, even counting from end of the array
3326backwards.
3327
7a4340ed 3328=item Modification of non-creatable hash value attempted, %s
a0d0e21e 3329
be771a83
GS
3330(P) You tried to make a hash value spring into existence, and it
3331couldn't be created for some peculiar reason.
a0d0e21e
LW
3332
333