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888aee59 1M=head1 NAME
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f39f21d8 3perldelta - what is new for perl v5.8.0
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4
5=head1 DESCRIPTION
6
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7This document describes differences between the 5.6.0 release and the
85.8.0 release.
9
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10=head1 Incompatible Changes
11
12=over 4
13
14=item *
15
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16The semantics of bless(REF, REF) were unclear and until someone proves
17it to make some sense, it is forbidden.
18
19=item *
20
21A reference to a reference now stringify as "REF(0x81485ec)" instead
22of "SCALAR(0x81485ec)" in order to be more consistent with the return
23value of ref().
24
25=item *
26
27The very dusty examples in the eg/ directory have been removed.
28Suggestions for new shiny examples welcome but the main issue is that
29the examples need to be documented, tested and (most importantly)
30maintained.
31
32=item *
33
34The obsolete chat2 library that should never have been allowed
35to escape the laboratory has been decommissioned.
36
37=item *
38
39The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
40recognised but now cause fatal errors. The previous behaviour of
41ignoring them by default and warning if requested was unacceptable
42since it, in a way, falsely promised that the features could be used.
43
44=item *
45
46The (bogus) escape sequences \8 and \9 now give an optional warning
47("Unrecognized escape passed through"). There is no need to \-escape
48any C<\w> character.
49
50=item *
51
52lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
53In future releases this may become a fatal error.
54
55=item *
56
57The long deprecated uppercase aliases for the string comparison
58operators (EQ, NE, LT, LE, GE, GT) have now been removed.
59
60=item *
61
62The regular expression captured submatches ($1, $2, ...) are now
63more consistently unset if the match fails, instead of leaving false
64data lying around in them.
65
66=item *
67
68The tr///C and tr///U features have been removed and will not return;
69the interface was a mistake. Sorry about that. For similar
70functionality, see pack('U0', ...) and pack('C0', ...).
71
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72=item *
73
74Although "you shouldn't do that", it was possible to write code that
75depends on Perl's hashed key order (Data::Dumper does this). The new
76algorithm "One-at-a-Time" produces a different hashed key order.
77More details are in L</"Performance Enhancements">.
78
79=item *
80
81The list of filenames from glob() (or <...>) is now by default sorted
82alphabetically to be csh-compliant. (bsd_glob() does still sort platform
83natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
84
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85=back
86
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87=head2 64-bit platforms and malloc
88
89If your pointers are 64 bits wide, the Perl malloc is no more being
90used because it simply does not work with 8-byte pointers. Also,
91usually the system malloc on such platforms are much better optimized
92for such large memory models than the Perl malloc.
93
94=head2 AIX Dynaloading
95
96The AIX dynaloading now uses in AIX releases 4.3 and newer the native
97dlopen interface of AIX instead of the old emulated interface. This
98change will probably break backward compatibility with compiled
99modules. The change was made to make Perl more compliant with other
100applications like modperl which are using the AIX native interface.
101
102=head2 Socket Extension Dynamic in VMS
103
104The Socket extension is now dynamically loaded instead of being
105statically built in. This may or may not be a problem with ancient
106TCP/IP stacks of VMS: we do not know since we weren't able to test
107Perl in such configurations.
108
109=head2 Different Definition of the Unicode Character Classes \p{In...}
110
111As suggested by the Unicode consortium, the Unicode character classes
112now prefer I<scripts> as opposed to I<blocks> (as defined by Unicode);
113in Perl, when the C<\p{In....}> and the C<\p{In....}> regular expression
114constructs are used. This has changed the definition of some of those
115character classes.
116
117The difference between scripts and blocks is that scripts are the
118glyphs used by a language or a group of languages, while the blocks
119are more artificial groupings of 256 characters based on the Unicode
120numbering.
121
122In general this change results in more inclusive Unicode character
123classes, but changes to the other direction also do take place:
124for example while the script C<Latin> includes all the Latin
125characters and their various diacritic-adorned versions, it
126does not include the various punctuation or digits (since they
127are not solely C<Latin>).
128
129Changes in the character class semantics may have happened if a script
130and a block happen to have the same name, for example C<Hebrew>.
131In such cases the script wins and C<\p{InHebrew}> now means the script
132definition of Hebrew. The block definition in still available,
133though, by appending C<Block> to the name: C<\p{InHebrewBlock}> means
134what C<\p{InHebrew}> meant in perl 5.6.0. For the full list
135of affected character classes, see L<perlunicode/Blocks>.
136
137=head2 Deprecations
138
139The current user-visible implementation of pseudo-hashes (the weird
140use of the first array element) is deprecated starting from Perl 5.8.0
141and will be removed in Perl 5.10.0, and the feature will be
142implemented differently. Not only is the current interface rather
143ugly, but the current implementation slows down normal array and hash
144use quite noticeably. The C<fields> pragma interface will remain
145available.
146
147The syntaxes C<@a->[...]> and C<@h->{...}> have now been deprecated.
148
149The suidperl is also considered to be too much a risk to continue
150maintaining and the suidperl code is likely to be removed in a future
151release.
152
153The C<package;> syntax (C<package> without an argument has been
154deprecated. Its semantics were never that clear and its
155implementation even less so. If you have used that feature to
156disallow all but fully qualified variables, C<use strict;> instead.
157
158The chdir(undef) and chdir('') behaviors to match chdir() has been
159deprecated. In future versions, chdir(undef) and chdir('') will
160simply fail.
161
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162=head1 Core Enhancements
163
164=over 4
165
166=item *
167
168C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
169in multiple arguments.)
170
171=item *
172
173my __PACKAGE__ $obj now works.
174
175=item *
176
177C<no Module;> now works even if there is no "sub unimport" in the Module.
178
179=item *
180
181The numerical comparison operators return C<undef> if either operand
182is a NaN. Previously the behaviour was unspecified.
183
184=item *
185
186C<pack('U0a*', ...)> can now be used to force a string to UTF8.
187
188=item *
189
190prototype(\&) is now available.
191
192=item *
193
194There is now an UNTIE method.
195
196=back
197
77c8cf41 198=head2 AUTOLOAD Is Now Lvaluable
f39f21d8 199
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200AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
201to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
202
203=head2 PerlIO is Now The Default
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204
205=over 4
206
207=item *
208
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209IO is now by default done via PerlIO rather than system's "stdio".
210PerlIO allows "layers" to be "pushed" onto a file handle to alter the
211handle's behaviour. Layers can be specified at open time via 3-arg
212form of open:
f39f21d8 213
77c8cf41 214 open($fh,'>:crlf :utf8', $path) || ...
f39f21d8 215
77c8cf41 216or on already opened handles via extended C<binmode>:
f39f21d8 217
77c8cf41 218 binmode($fh,':encoding(iso-8859-7)');
f39f21d8 219
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220The built-in layers are: unix (low level read/write), stdio (as in
221previous Perls), perlio (re-implementation of stdio buffering in a
222portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
223but available on any platform). A mmap layer may be available if
224platform supports it (mostly UNIXes).
f39f21d8 225
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226Layers to be applied by default may be specified via the 'open' pragma.
227
228See L</"Installation and Configuration Improvements"> for the effects
229of PerlIO on your architecture name.
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230
231=item *
232
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233File handles can be marked as accepting Perl's internal encoding of Unicode
234(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
f39f21d8 235
77c8cf41 236 open($fh,">:utf8","Uni.txt");
f39f21d8 237
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238Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
239for you since it's not UTF-8 what you will be getting but instead
240UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
241http://www.unicode.org/unicode/reports/tr16/ for more information.
242In future releases this naming may change.
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243
244=item *
245
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246File handles can translate character encodings from/to Perl's internal
247Unicode form on read/write via the ":encoding()" layer.
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248
249=item *
250
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251File handles can be opened to "in memory" files held in Perl scalars via:
252
253 open($fh,'>', \$variable) || ...
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254
255=item *
256
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257Anonymous temporary files are available without need to
258'use FileHandle' or other module via
f39f21d8 259
77c8cf41 260 open($fh,"+>", undef) || ...
f39f21d8 261
77c8cf41 262That is a literal undef, not an undefined value.
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263
264=item *
265
77c8cf41 266The list form of C<open> is now implemented for pipes (at least on UNIX):
f39f21d8 267
77c8cf41 268 open($fh,"-|", 'cat', '/etc/motd')
f39f21d8 269
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270creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
271the child process.
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272
273=item *
274
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275The following builtin functions are now overridable: chop(), chomp(),
276each(), keys(), pop(), push(), shift(), splice(), unshift().
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277
278=item *
279
77c8cf41 280Formats now support zero-padded decimal fields.
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281
282=item *
283
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284Perl now tries internally to use integer values in numeric conversions
285and basic arithmetics (+ - * /) if the arguments are integers, and
286tries also to keep the results stored internally as integers.
287This change leads into often slightly faster and always less lossy
288arithmetics. (Previously Perl always preferred floating point numbers
289in its math.)
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290
291=item *
292
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293The printf() and sprintf() now support parameter reordering using the
294C<%\d+\$> and C<*\d+\$> syntaxes. For example
f39f21d8 295
77c8cf41 296 print "%2\$s %1\$s\n", "foo", "bar";
f39f21d8 297
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298will print "bar foo\n"; This feature helps in writing
299internationalised software.
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300
301=item *
302
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303Unicode in general should be now much more usable. Unicode can be
304used in hash keys, Unicode in regular expressions should work now,
305Unicode in tr/// should work now (though tr/// seems to be a
306particularly tricky to get right, so you have been warned)
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307
308=item *
309
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310The Unicode Character Database coming with Perl has been upgraded
311to Unicode 3.1. For more information, see http://www.unicode.org/,
312and http://www.unicode.org/unicode/reports/tr27/
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314For developers interested in enhancing Perl's Unicode capabilities:
315almost all the UCD files are included with the Perl distribution in
316the lib/unicode subdirectory. The most notable omission, for space
317considerations, is the Unihan database.
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318
319=item *
320
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321The Unicode character classes \p{Blank} and \p{SpacePerl} have been
322added. "Blank" is like C isblank(), that is, it contains only
323"horizontal whitespace" (the space character is, the newline isn't),
324and the "SpacePerl" is the Unicode equivalent of C<\s> (\p{Space}
325isn't, since that includes the vertical tabulator character, whereas
326C<\s> doesn't.)
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327
328=back
329
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330=head2 Signals Are Now Safe
331
332Perl used to be fragile in that signals arriving at inopportune moments
333could corrupt Perl's internal state.
334
335=head2 Understanding of Numbers
336
337In general a lot of fixing has happened in the area of Perl's
338understanding of numbers, both integer and floating point. Since in
339many systems the standard number parsing functions like C<strtoul()>
340and C<atof()> seem to have bugs, Perl tries to work around their
341deficiencies. This results hopefully in more accurate numbers.
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342
343=over 4
344
345=item *
346
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347The rules for allowing underscores (underbars) in numeric constants
348have been relaxed and simplified: now you can have an underscore
349B<between digits>.
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350
351=item *
352
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353GMAGIC (right-hand side magic) could in many cases such as string
354concatenation be invoked too many times.
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355
356=item *
357
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358Lexicals I: lexicals outside an eval "" weren't resolved
359correctly inside a subroutine definition inside the eval "" if they
360were not already referenced in the top level of the eval""ed code.
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361
362=item *
363
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364Lexicals II: lexicals leaked at file scope into subroutines that
365were declared before the lexicals.
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366
367=item *
368
77c8cf41 369Lvalue subroutines can now return C<undef> in list context.
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370
371=item *
372
77c8cf41 373The C<op_clear> and C<op_null> are now exported.
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374
375=item *
376
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377A new special regular expression variable has been introduced:
378C<$^N>, which contains the most-recently closed group (submatch).
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379
380=item *
381
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382L<utime> now supports C<utime undef, undef, @files> to change the
383file timestamps to the current time.
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384
385=item *
386
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387The Perl parser has been stress tested using both random input and
388Markov chain input.
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389
390=item *
391
77c8cf41 392C<eval "v200"> now works.
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393
394=item *
395
77c8cf41 396VMS now works under PerlIO.
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397
398=item *
399
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400END blocks are now run even if you exit/die in a BEGIN block.
401The execution of END blocks is now controlled by
402PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
403behaviour for perl embedders. This will default in 5.10. See
404L<perlembed>.
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405
406=back
407
77c8cf41 408=head1 Modules and Pragmata
f39f21d8 409
77c8cf41 410=head2 New Modules
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411
412=over 4
413
414=item *
415
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416File::Temp allows one to create temporary files and directories in an
417easy, portable, and secure way.
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418
419=item *
420
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421Storable gives persistence to Perl data structures by allowing the
422storage and retrieval of Perl data to and from files in a fast and
423compact binary format.
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424
425=item *
426
427B::Concise, by Stephen McCamant, is a new compiler backend for
428walking the Perl syntax tree, printing concise info about ops.
429The output is highly customisable.
430
431See L<B::Concise> for more information.
432
433=item *
434
435Class::ISA, by Sean Burke, for reporting the search path for a
436class's ISA tree, has been added.
437
438See L<Class::ISA> for more information.
439
440=item *
441
442Cwd has now a split personality: if possible, an extension is used,
443(this will hopefully be both faster and more secure and robust) but
444if not possible, the familiar Perl library implementation is used.
445
446=item *
447
448Digest, a frontend module for calculating digests (checksums),
449from Gisle Aas, has been added.
450
451See L<Digest> for more information.
452
453=item *
454
455Digest::MD5 for calculating MD5 digests (checksums), by Gisle Aas,
456has been added.
457
458 use Digest::MD5 'md5_hex';
459
460 $digest = md5_hex("Thirsty Camel");
461
462 print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
463
464NOTE: the MD5 backward compatibility module is deliberately not
465included since its use is discouraged.
466
467See L<Digest::MD5> for more information.
468
469=item *
470
471Encode, by Nick Ing-Simmons, provides a mechanism to translate
472between different character encodings. Support for Unicode,
473ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
474compiled in to the module. Several other encodings (like Japanese,
475Chinese, and MacIntosh encodings) are included and will be loaded at
476runtime.
477
478Any encoding supported by Encode module is also available to the
479":encoding()" layer if PerlIO is used.
480
481See L<Encode> for more information.
482
483=item *
484
485Filter::Simple is an easy-to-use frontend to Filter::Util::Call,
486from Damian Conway.
487
488 # in MyFilter.pm:
489
490 package MyFilter;
491
492 use Filter::Simple sub {
493 while (my ($from, $to) = splice @_, 0, 2) {
494 s/$from/$to/g;
495 }
496 };
497
498 1;
499
500 # in user's code:
501
502 use MyFilter qr/red/ => 'green';
503
504 print "red\n"; # this code is filtered, will print "green\n"
505 print "bored\n"; # this code is filtered, will print "bogreen\n"
506
507 no MyFilter;
508
509 print "red\n"; # this code is not filtered, will print "red\n"
510
511See L<Filter::Simple> for more information.
512
513=item *
514
515Filter::Util::Call, by Paul Marquess, provides you with the
516framework to write I<Source Filters> in Perl. For most uses
517the frontend Filter::Simple is to be preferred.
518See L<Filter::Util::Call> for more information.
519
520=item *
521
522Locale::Constants, Locale::Country, Locale::Currency, and Locale::Language,
523from Neil Bowers, have been added. They provide the codes for various
524locale standards, such as "fr" for France, "usd" for US Dollar, and
525"jp" for Japanese.
526
527 use Locale::Country;
528
529 $country = code2country('jp'); # $country gets 'Japan'
530 $code = country2code('Norway'); # $code gets 'no'
531
532See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
533and L<Locale::Language> for more information.
534
535=item *
536
537MIME::Base64, by Gisle Aas, allows you to encode data in base64.
538
539 use MIME::Base64;
540
541 $encoded = encode_base64('Aladdin:open sesame');
542 $decoded = decode_base64($encoded);
543
544 print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
545
546See L<MIME::Base64> for more information.
547
548=item *
549
550MIME::QuotedPrint, by Gisle Aas, allows you to encode data in
551quoted-printable encoding.
552
553 use MIME::QuotedPrint;
554
555 $encoded = encode_qp("Smiley in Unicode: \x{263a}");
556 $decoded = decode_qp($encoded);
557
558 print $encoded, "\n"; # "Smiley in Unicode: =263A"
559
560MIME::QuotedPrint has been enhanced to provide the basic methods
561necessary to use it with PerlIO::Via as in :
562
563 use MIME::QuotedPrint;
564 open($fh,">Via(MIME::QuotedPrint)",$path)
565
566See L<MIME::QuotedPrint> for more information.
567
568=item *
569
570PerlIO::Scalar, by Nick Ing-Simmons, provides the implementation of
571IO to "in memory" Perl scalars as discussed above. It also serves as
572an example of a loadable layer. Other future possibilities include
573PerlIO::Array and PerlIO::Code. See L<PerlIO::Scalar> for more
574information.
575
576=item *
577
578PerlIO::Via, by Nick Ing-Simmons, acts as a PerlIO layer and wraps
579PerlIO layer functionality provided by a class (typically implemented
580in perl code).
581
582 use MIME::QuotedPrint;
583 open($fh,">Via(MIME::QuotedPrint)",$path)
584
585This will automatically convert everything output to C<$fh>
586to Quoted-Printable. See L<PerlIO::Via> for more information.
587
588=item *
589
590Pod::Text::Overstrike, by Joe Smith, has been added.
591It converts POD data to formatted overstrike text.
592See L<Pod::Text::Overstrike> for more information.
593
594=item *
595
596Switch from Damian Conway has been added. Just by saying
597
598 use Switch;
599
600you have C<switch> and C<case> available in Perl.
601
602 use Switch;
603
604 switch ($val) {
605
606 case 1 { print "number 1" }
607 case "a" { print "string a" }
608 case [1..10,42] { print "number in list" }
609 case (@array) { print "number in list" }
610 case /\w+/ { print "pattern" }
611 case qr/\w+/ { print "pattern" }
612 case (%hash) { print "entry in hash" }
613 case (\%hash) { print "entry in hash" }
614 case (\&sub) { print "arg to subroutine" }
615 else { print "previous case not true" }
616 }
617
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618See L<Switch> for more information.
619
620=item *
621
622Text::Balanced from Damian Conway has been added, for
623extracting delimited text sequences from strings.
624
625 use Text::Balanced 'extract_delimited';
626
627 ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
628
629$a will be "'never say never'", $b will be ', he never said'.
630
631In addition to extract_delimited() there are also extract_bracketed(),
632extract_quotelike(), extract_codeblock(), extract_variable(),
633extract_tagged(), extract_multiple(), gen_delimited_pat(), and
634gen_extract_tagged(). With these you can implement rather advanced
635parsing algorithms. See L<Text::Balanced> for more information.
636
637=item *
638
639Tie::RefHash::Nestable, by Edward Avis, allows storing hash references
640(unlike the standard Tie::RefHash) The module is contained within
641Tie::RefHash.
642
643=item *
644
645XS::Typemap, by Tim Jenness, is a test extension that exercises XS
646typemaps. Nothing gets installed but for extension writers the code
647is worth studying.
648
649=item *
650
651L<Attribute::Handlers> - Simpler definition of attribute handlers
652
653=item *
654
655L<ExtUtils::Constant> - generate XS code to import C header constants
656
657=item *
658
659L<I18N::Langinfo> - query locale information
660
661=item *
662
663L<I18N::LangTags> - functions for dealing with RFC3066-style language tags
664
665=item *
666
667L<libnet> - a collection of perl5 modules related to network programming
668
669Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
670
671=item *
672
673L<List::Util> - selection of general-utility list subroutines
674
675=item *
676
677L<Locale::Maketext> - framework for localization
678
679=item *
680
681L<Memoize> - Make your functions faster by trading space for time
682
683=item *
684
685L<NEXT> - pseudo-class for method redispatch
686
687=item *
688
689L<Scalar::Util> - selection of general-utility scalar subroutines
690
691=item *
692
693L<Test::More> - yet another framework for writing test scripts
694
695=item *
696
697L<Test::Simple> - Basic utilities for writing tests
698
699=item *
700
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701L<threads> - interpreter threads
702
703=item *
704
705L<threads::shared> - data sharing for interpreter threads
706
707=item *
708
77c8cf41
JH
709L<Time::HiRes> - high resolution ualarm, usleep, and gettimeofday
710
711=item *
712
713L<Time::Piece> - Object Oriented time objects
714
715(Previously known as L<Time::Object>.)
716
717=item *
718
719L<Time::Seconds> - a simple API to convert seconds to other date values
720
721=item *
722
888aee59
JH
723L<Unicode::CD> - Unicode Character Database
724
725=item *
726
727Unicode::Collate - Unicode collation
728
729=item *
730
731Unicode::Normalize - Unicode normalization
77c8cf41
JH
732
733=back
734
735=head2 Updated And Improved Modules and Pragmata
736
737=over 4
738
739=item *
740
741The following independently supported modules have been updated to
742newer versions from CPAN: CGI, CPAN, DB_File, File::Spec, Getopt::Long,
743the podlators bundle, Pod::LaTeX, Pod::Parser, Term::ANSIColor, Test.
744
745=item *
746
747Bug fixes and minor enhancements have been applied to B::Deparse,
748Data::Dumper, IO::Poll, IO::Socket::INET, Math::BigFloat,
749Math::Complex, Math::Trig, Net::protoent, the re pragma, SelfLoader,
750Sys::SysLog, Test::Harness, Text::Wrap, UNIVERSAL, and the warnings
751pragma.
752
753=item *
754
755The attributes::reftype() now works on tied arguments.
756
757=item *
758
759AutoLoader can now be disabled with C<no AutoLoader;>,
760
761=item *
762
763The English module can now be used without the infamous performance
764hit by saying
765
766 use English '-no_performance_hit';
767
768(Assuming, of course, that one doesn't need the troublesome variables
769C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
770C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
771
772=item *
773
774File::Find now has pre- and post-processing callbacks. It also
775correctly changes directories when chasing symbolic links. Callbacks
776(naughtily) exiting with "next;" instead of "return;" now work.
777
778=item *
779
780File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
781prototype mismatch with CORE::glob().
782
783=item *
784
785IPC::Open3 now allows the use of numeric file descriptors.
786
787=item *
788
789use lib now works identically to @INC. Removing directories
790with 'no lib' now works.
791
792=item *
793
794C<%INC> now localised in a Safe compartment so that use/require work.
795
796=item *
797
798The Shell module now has an OO interface.
799
800=item *
801
802B::Deparse should be now more robust. It still far from providing a full
803round trip for any random piece of Perl code, though, and is under active
804development: expect more robustness in 5.7.2.
805
806=item *
807
808Class::Struct can now define the classes in compile time.
809
810=item *
811
812Math::BigFloat has undergone much fixing, and in addition the fmod()
813function now supports modulus operations.
814
815(The fixed Math::BigFloat module is also available in CPAN for those
816who can't upgrade their Perl: http://www.cpan.org/authors/id/J/JP/JPEACOCK/)
817
818=item *
819
820Devel::Peek now has an interface for the Perl memory statistics
821(this works only if you are using perl's malloc, and if you have
822compiled with debugging).
823
824=item *
825
826IO::Socket has now atmark() method, which returns true if the socket
827is positioned at the out-of-band mark. The method is also exportable
828as a sockatmark() function.
829
830=item *
831
832IO::Socket::INET has support for ReusePort option (if your platform
833supports it). The Reuse option now has an alias, ReuseAddr. For clarity
834you may want to prefer ReuseAddr.
835
836=item *
837
838Net::Ping has been enhanced. There is now "external" protocol which
839uses Net::Ping::External module which runs external ping(1) and parses
840the output. An alpha version of Net::Ping::External is available in
841CPAN and in 5.7.2 the Net::Ping::External may be integrated to Perl.
842
843=item *
844
845The C<open> pragma allows layers other than ":raw" and ":crlf" when
846using PerlIO.
847
848=item *
849
850POSIX::sigaction() is now much more flexible and robust.
851You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
852handlers, installing new handlers was not atomic.
853
854=item *
855
856The Test module has been significantly enhanced. Its use is
857greatly recommended for module writers.
858
859=item *
860
861The utf8:: name space (as in the pragma) provides various
862Perl-callable functions to provide low level access to Perl's
863internal Unicode representation. At the moment only length()
864has been implemented.
865
866=back
867
868The following modules have been upgraded from the versions at CPAN:
869CPAN, CGI, DB_File, File::Temp, Getopt::Long, Pod::Man, Pod::Text,
870Storable, Text-Tabs+Wrap.
871
872=item *
873
874L<B::Deparse> module has been significantly enhanced. It now
875can deparse almost all of the standard test suite (so that the
876tests still succeed). There is a make target "test.deparse"
877for trying this out.
878
879=item *
880
881L<Class::Struct> now assigns the array/hash element if the accessor
882is called with an array/hash element as the B<sole> argument.
883
884=item *
885
886L<Cwd> extension is now (even) faster.
887
888=item *
889
890L<DB_File> extension has been updated to version 1.77.
f39f21d8
JH
891
892=item *
893
77c8cf41
JH
894L<Fcntl>, L<Socket>, and L<Sys::Syslog> have been rewritten to use the
895new-style constant dispatch section (see L<ExtUtils::Constant>).
f39f21d8 896
77c8cf41 897=item *
f39f21d8 898
77c8cf41
JH
899L<File::Find> is now (again) reentrant. It also has been made
900more portable.
f39f21d8 901
77c8cf41 902=item *
f39f21d8 903
77c8cf41
JH
904L<File::Glob> now supports C<GLOB_LIMIT> constant to limit the
905size of the returned list of filenames.
f39f21d8
JH
906
907=item *
908
77c8cf41
JH
909L<IO::Socket::INET> now supports C<LocalPort> of zero (usually meaning
910that the operating system will make one up.)
f39f21d8
JH
911
912=item *
913
77c8cf41
JH
914The L<vars> pragma now supports declaring fully qualified variables.
915(Something that C<our()> does not and will not support.)
f39f21d8 916
888aee59
JH
917=item *
918
919List::Util now has shuffle() for randomizing a list.
920
f39f21d8
JH
921=back
922
77c8cf41 923=head1 Utility Changes
f39f21d8
JH
924
925=over 4
926
927=item *
928
77c8cf41
JH
929The Emacs perl mode (emacs/cperl-mode.el) has been updated to version
9304.31.
f39f21d8
JH
931
932=item *
933
77c8cf41
JH
934Perlbug is now much more robust. It also sends the bug report to
935perl.org, not perl.com.
f39f21d8
JH
936
937=item *
938
77c8cf41
JH
939The perlcc utility has been rewritten and its user interface (that is,
940command line) is much more like that of the UNIX C compiler, cc.
f39f21d8 941
77c8cf41
JH
942=item *
943
944The xsubpp utility for extension writers now understands POD
945documentation embedded in the *.xs files.
f39f21d8
JH
946
947=item *
948
77c8cf41 949h2xs now produces template README.
f39f21d8
JH
950
951=item *
952
77c8cf41
JH
953s2p has been completely rewritten in Perl. (It is in fact a full
954implementation of sed in Perl.)
f39f21d8
JH
955
956=item *
957
77c8cf41 958xsubpp now supports OUT keyword.
f39f21d8
JH
959
960=item *
961
77c8cf41 962The F<emacs/e2ctags.pl> is now much faster.
f39f21d8
JH
963
964=item *
965
77c8cf41 966L<h2ph> now supports C trigraphs.
f39f21d8
JH
967
968=item *
969
77c8cf41
JH
970L<h2xs> uses the new L<ExtUtils::Constant> module which will affect
971newly created extensions that define constants. Since the new code is
972more correct (if you have two constants where the first one is a
973prefix of the second one, the first constant B<never> gets defined),
974less lossy (it uses integers for integer constant, as opposed to the
975old code that used floating point numbers even for integer constants),
976and slightly faster, you might want to consider regenerating your
977extension code (the new scheme makes regenerating easy).
978L<h2xs> now also supports C trigraphs.
f39f21d8
JH
979
980=item *
981
77c8cf41 982L<libnetcfg> has been added to configure the libnet.
f39f21d8
JH
983
984=item *
985
77c8cf41
JH
986The F<Pod::Html> (and thusly L<pod2html>) now allows specifying
987a cache directory.
f39f21d8
JH
988
989=back
990
77c8cf41 991=head1 New Documentation
f39f21d8
JH
992
993=over 4
994
995=item *
996
77c8cf41
JH
997perl56delta details the changes between the 5.005 release and the
9985.6.0 release.
f39f21d8
JH
999
1000=item *
1001
77c8cf41 1002perldebtut is a Perl debugging tutorial.
f39f21d8 1003
77c8cf41 1004=item *
f39f21d8 1005
77c8cf41
JH
1006perlebcdic contains considerations for running Perl on EBCDIC platforms.
1007Note that unfortunately EBCDIC platforms that used to supported back in
1008Perl 5.005 are still unsupported by Perl 5.7.0; the plan, however, is to
1009bring them back to the fold.
f39f21d8 1010
77c8cf41
JH
1011=item *
1012
888aee59
JH
1013perlintro is a gentle introduction to Perl.
1014
1015=item *
1016
1017perlmodstyle is a style guide for writing modules.
1018
1019=item *
1020
77c8cf41 1021perlnewmod tells about writing and submitting a new module.
f39f21d8
JH
1022
1023=item *
1024
888aee59
JH
1025perlpod has been rewritten to be clearer and to record the best
1026practices gathered over the years.
1027
1028=item *
1029
1030perlpodstyle is a more formal specification of the pod format,
1031mainly of interest for writers of pod applications, not to
1032people writing in pod.
1033
1034=item *
1035
77c8cf41
JH
1036perlposix-bc explains using Perl on the POSIX-BC platform
1037(an EBCDIC mainframe platform).
f39f21d8
JH
1038
1039=item *
1040
77c8cf41 1041perlretut is a regular expression tutorial.
f39f21d8
JH
1042
1043=item *
1044
77c8cf41
JH
1045perlrequick is a regular expressions quick-start guide.
1046Yes, much quicker than perlretut.
f39f21d8 1047
77c8cf41 1048=item *
f39f21d8 1049
888aee59
JH
1050perltootc has been renamed as perltooc (to not to conflict
1051with perltoot in filesystem restricted to "8.3" names)
1052
1053=item *
1054
1055perluniintro is an introduction to using Unicode in Perl
1056(perlunicode is more of a reference)
1057
1058=item *
1059
77c8cf41
JH
1060perlutil explains the command line utilities packaged with the Perl
1061distribution.
1062
1063=back
f39f21d8
JH
1064
1065=head2 perlclib
1066
1067Internal replacements for standard C library functions.
1068(Interesting only for extension writers and Perl core hackers.)
1069
1070=head2 perliol
1071
1072Internals of PerlIO with layers.
1073
1074=head2 README.aix
1075
1076Documentation on compiling Perl on AIX has been added. AIX has
1077several different C compilers and getting the right patch level
1078is essential. On install README.aix will be installed as L<perlaix>.
1079
1080=head2 README.bs2000
1081
1082Documentation on compiling Perl on the POSIX-BC platform (an EBCDIC
1083mainframe environment) has been added.
1084
1085This was formerly known as README.posix-bc but the name was considered
1086to be too confusing (it has nothing to do with the POSIX module or the
1087POSIX standard). On install README.bs2000 will be installed as L<perlbs2000>.
1088
1089=head2 README.macos
1090
1091In perl 5.7.1 (and in the 5.6.1) the MacPerl sources have been
1092synchronised with the standard Perl sources. To compile MacPerl
1093some additional steps are required, and this file documents those
1094steps. On install README.macos will be installed as L<perlmacos>.
1095
1096=head2 README.mpeix
1097
1098The README.mpeix has been podified, which means that this information
1099about compiling and using Perl on the MPE/iX miniframe platform will
1100be installed as L<perlmpeix>.
1101
1102=head2 README.solaris
1103
1104README.solaris has been created and Solaris wisdom from elsewhere
1105in the Perl documentation has been collected there. On install
1106README.solaris will be installed as L<perlsolaris>.
1107
1108=head2 README.vos
1109
1110The README.vos has been podified, which means that this information
1111about compiling and using Perl on the Stratus VOS miniframe platform
1112will be installed as L<perlvos>.
1113
77c8cf41
JH
1114=head2 Porting/repository.pod
1115
1116Documentation on how to use the Perl source repository has been added.
1117
1118=over 4
1119
1120=item *
1121
1122L<Locale::Maketext::TPJ13> is an article about software localization,
1123originally published in The Perl Journal #13, republished here with
1124kind permission.
1125
1126=item *
1127
1128More README.$PLATFORM files have been converted into pod, which also
1129means that they also be installed as perl$PLATFORM documentation
1130files. The new files are L<perlapollo>, L<perlbeos>, L<perldgux>,
1131L<perlhurd>, L<perlmint>, L<perlnetware>, L<perlplan9>, L<perlqnx>,
1132and L<perltru64>.
1133
1134=item *
1135
1136The F<Todo> and F<Todo-5.6> files have been merged into L<perltodo>.
1137
1138=item *
1139
1140Use of the F<gprof> tool to profile Perl has been documented in
1141L<perlhack>. There is a make target "perl.gprof" for generating a
1142gprofiled Perl executable.
1143
1144=back
1145
1146=head1 Performance Enhancements
1147
1148=over 4
1149
1150=item *
1151
1152map() that changes the size of the list should now work faster.
1153
1154=item *
1155
1156sort() has been changed to use mergesort internally as opposed to the
1157earlier quicksort. For very small lists this may result in slightly
1158slower sorting times, but in general the speedup should be at least
115920%. Additional bonuses are that the worst case behaviour of sort()
1160is now better (in computer science terms it now runs in time O(N log N),
1161as opposed to quicksort's Theta(N**2) worst-case run time behaviour),
1162and that sort() is now stable (meaning that elements with identical
1163keys will stay ordered as they were before the sort).
1164
1165=item *
1166
1167Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
1168(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
1169reasonably fast while producing a much better spread of values than
1170the old hashing algorithm (originally by Chris Torek, later tweaked by
1171Ilya Zakharevich). Hash values output from the algorithm on a hash of
1172all 3-char printable ASCII keys comes much closer to passing the
1173DIEHARD random number generation tests. According to perlbench, this
1174change has not affected the overall speed of Perl.
1175
1176=item *
1177
1178unshift() should now be noticeably faster.
1179
1180=back
1181
1182=head1 Installation and Configuration Improvements
1183
1184=head2 Generic Improvements
1185
1186=over 4
1187
1188=item *
1189
1190INSTALL now explains how you can configure Perl to use 64-bit
1191integers even on non-64-bit platforms.
1192
1193=item *
1194
1195Policy.sh policy change: if you are reusing a Policy.sh file
1196(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
1197Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
1198them will now be changed to the new prefix, /foo/bar. (Previously
1199only $prefix changed.) If you do not like this new behaviour,
1200specify prefix, siteprefix, and vendorprefix explicitly.
1201
1202=item *
1203
1204A new optional location for Perl libraries, otherlibdirs, is available.
1205It can be used for example for vendor add-ons without disturbing Perl's
1206own library directories.
1207
1208=item *
1209
1210In many platforms the vendor-supplied 'cc' is too stripped-down to
1211build Perl (basically, 'cc' doesn't do ANSI C). If this seems
1212to be the case and 'cc' does not seem to be the GNU C compiler
1213'gcc', an automatic attempt is made to find and use 'gcc' instead.
1214
1215=item *
1216
1217gcc needs to closely track the operating system release to avoid
1218build problems. If Configure finds that gcc was built for a different
1219operating system release than is running, it now gives a clearly visible
1220warning that there may be trouble ahead.
1221
1222=item *
1223
1224If binary compatibility with the 5.005 release is not wanted, Configure
1225no longer suggests including the 5.005 modules in @INC.
1226
1227=item *
1228
1229Configure C<-S> can now run non-interactively.
1230
1231=item *
1232
1233configure.gnu now works with options with whitespace in them.
f39f21d8 1234
77c8cf41 1235=item *
f39f21d8 1236
77c8cf41 1237installperl now outputs everything to STDERR.
f39f21d8 1238
77c8cf41
JH
1239=item *
1240
1241$Config{byteorder} is now computed dynamically (this is more robust
1242with "fat binaries" where an executable image contains binaries for
1243more than one binary platform.)
f39f21d8
JH
1244
1245=item *
1246
1247Because PerlIO is now the default on most platforms, "-perlio" doesn't
1248get appended to the $Config{archname} (also known as $^O) anymore.
1249Instead, if you explicitly choose not to use perlio (Configure command
1250line option -Uuseperlio), you will get "-stdio" appended.
1251
1252=item *
1253
1254Another change related to the architecture name is that "-64all"
1255(-Duse64bitall, or "maximally 64-bit") is appended only if your
1256pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
1257
1258=item *
1259
1260APPLLIB_EXP, a less-know configuration-time definition, has been
1261documented. It can be used to prepend site-specific directories
1262to Perl's default search path (@INC), see INSTALL for information.
1263
1264=item *
1265
1266Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
1267has been documented in INSTALL.
1268
1269=item *
1270
1271If you are on IRIX or Tru64 platforms, new profiling/debugging options
1272have been added, see L<perlhack> for more information about pixie and
1273Third Degree.
1274
77c8cf41
JH
1275=item *
1276
1277In AFS installations one can configure the root of the AFS to be
1278somewhere else than the default F</afs> by using the Configure
1279parameter C<-Dafsroot=/some/where/else>.
1280
1281=item *
1282
1283The version of Berkeley DB used when the Perl (and, presumably, the
1284DB_File extension) was built is now available as
1285C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
1286from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
1287DB_VERSION_PATCH_CFG> from C.
1288
1289=item *
1290
1291The Thread extension is now not built at all under ithreads
1292(C<Configure -Duseithreads>) because it wouldn't work anyway (the
1293Thread extension requires being Configured with C<-Duse5005threads>).
1294
1295=item *
1296
1297The C<B::Deparse> compiler backend has been so significantly improved
1298that almost the whole Perl test suite passes after being deparsed. A
1299make target has been added to help in further testing: C<make test.deparse>.
1300
f39f21d8
JH
1301=back
1302
1303=head2 New Or Improved Platforms
1304
1305For the list of platforms known to support Perl,
1306see L<perlport/"Supported Platforms">.
1307
1308=over 4
1309
1310=item *
1311
1312AIX dynamic loading should be now better supported.
1313
1314=item *
1315
1316After a long pause, AmigaOS has been verified to be happy with Perl.
1317
1318=item *
1319
1320EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
1321have been regained. Many test suite tests still fail and the
1322co-existence of Unicode and EBCDIC isn't quite settled, but the
1323situation is much better than with Perl 5.6. See L<perlos390>,
1324L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
1325
1326=item *
1327
1328Building perl with -Duseithreads or -Duse5005threads now works under
1329HP-UX 10.20 (previously it only worked under 10.30 or later). You will
1330need a thread library package installed. See README.hpux.
1331
1332=item *
1333
1334MacOS Classic (MacPerl has of course been available since
1335perl 5.004 but now the source code bases of standard Perl
1336and MacPerl have been synchronised)
1337
1338=item *
1339
1340NCR MP-RAS is now supported.
1341
1342=item *
1343
1344NonStop-UX is now supported.
1345
1346=item *
1347
1348Amdahl UTS is now supported.
1349
1350=item *
1351
1352z/OS (formerly known as OS/390, formerly known as MVS OE) has now
1353support for dynamic loading. This is not selected by default,
1354however, you must specify -Dusedl in the arguments of Configure.
1355
f39f21d8
JH
1356=item *
1357
77c8cf41
JH
1358AIX should now work better with gcc, threads, and 64-bitness. Also the
1359long doubles support in AIX should be better now. See L<perlaix>.
f39f21d8
JH
1360
1361=item *
1362
77c8cf41 1363AtheOS (http://www.atheos.cx/) is a new platform.
f39f21d8 1364
77c8cf41 1365=item *
f39f21d8 1366
77c8cf41 1367DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
f39f21d8
JH
1368
1369=item *
1370
77c8cf41 1371DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
f39f21d8
JH
1372
1373=item *
1374
77c8cf41
JH
1375Several MacOS (Classic) portability patches have been applied. We
1376hope to get a fully working port by 5.8.0. (The remaining problems
1377relate to the changed IO model of Perl.) See L<perlmacos>.
f39f21d8
JH
1378
1379=item *
1380
77c8cf41
JH
1381MacOS X (or Darwin) should now be able to build Perl even on HFS+
1382filesystems. (The case-insensitivity confused the Perl build process.)
f39f21d8 1383
77c8cf41 1384=item *
f39f21d8 1385
77c8cf41 1386NetWare from Novell is now supported. See L<perlnetware>.
f39f21d8 1387
77c8cf41 1388=item *
f39f21d8 1389
77c8cf41 1390The Amdahl UTS UNIX mainframe platform is now supported.
f39f21d8 1391
888aee59
JH
1392=item *
1393
1394WinCE is now supported. See L<perlce>.
1395
1396=item *
1397
1398If you have CPAN access you can during specify extra modules to
1399Configure to build and install with Perl using the -Dextras=...
1400option. See INSTALL for more details.
1401
1402=item *
1403
1404In addition to config.over a new override file, config.arch, is
1405available. That is supposed to be used by hints file writers for
1406architecture-wide changes (as opposed to config.over which is for
1407site-wide changes).
1408
1409=item *
1410
1411Guidelines of how to construct minimal Perl installations have
1412been added to INSTALL.
1413
1414=item *
1415
1416For Perl developers several new make targets for profiling
1417have been added, see L<perlhack>.
1418
f39f21d8
JH
1419=back
1420
1421=head1 Selected Bug Fixes
1422
f39f21d8
JH
1423=over 4
1424
1425=item *
1426
77c8cf41
JH
1427Several debugger fixes: exit code now reflects the script exit code,
1428condition C<"0"> now treated correctly, the C<d> command now checks
1429line number, the C<$.> no longer gets corrupted, all debugger output now
1430goes correctly to the socket if RemotePort is set.
f39f21d8
JH
1431
1432=item *
1433
77c8cf41 1434C<*foo{FORMAT}> now works.
f39f21d8
JH
1435
1436=item *
1437
77c8cf41 1438Lexical warnings now propagating correctly between scopes.
f39f21d8
JH
1439
1440=item *
1441
77c8cf41 1442Line renumbering with eval and C<#line> now works.
f39f21d8
JH
1443
1444=item *
1445
77c8cf41 1446Fixed numerous memory leaks, especially in eval "".
f39f21d8
JH
1447
1448=item *
1449
77c8cf41
JH
1450Modulus of unsigned numbers now works (4063328477 % 65535 used to
1451return 27406, instead of 27047).
f39f21d8
JH
1452
1453=item *
1454
77c8cf41
JH
1455Some "not a number" warnings introduced in 5.6.0 eliminated to be
1456more compatible with 5.005. Infinity is now recognised as a number.
f39f21d8
JH
1457
1458=item *
1459
77c8cf41 1460our() variables will not cause "will not stay shared" warnings.
f39f21d8
JH
1461
1462=item *
1463
77c8cf41 1464pack "Z" now correctly terminates the string with "\0".
f39f21d8
JH
1465
1466=item *
1467
77c8cf41
JH
1468Fix password routines which in some shadow password platforms
1469(e.g. HP-UX) caused getpwent() to return every other entry.
f39f21d8
JH
1470
1471=item *
1472
77c8cf41 1473printf() no longer resets the numeric locale to "C".
f39f21d8
JH
1474
1475=item *
1476
77c8cf41 1477C<q(a\\b)> now parses correctly as C<'a\\b'>.
f39f21d8
JH
1478
1479=item *
1480
77c8cf41
JH
1481Printing quads (64-bit integers) with printf/sprintf now works
1482without the q L ll prefixes (assuming you are on a quad-capable platform).
f39f21d8
JH
1483
1484=item *
1485
77c8cf41 1486Regular expressions on references and overloaded scalars now work.
f39f21d8
JH
1487
1488=item *
1489
77c8cf41 1490scalar() now forces scalar context even when used in void context.
f39f21d8
JH
1491
1492=item *
1493
77c8cf41
JH
1494sort() arguments are now compiled in the right wantarray context
1495(they were accidentally using the context of the sort() itself).
f39f21d8
JH
1496
1497=item *
1498
77c8cf41
JH
1499Changed the POSIX character class C<[[:space:]]> to include the (very
1500rare) vertical tab character. Added a new POSIX-ish character class
1501C<[[:blank:]]> which stands for horizontal whitespace (currently,
1502the space and the tab).
f39f21d8
JH
1503
1504=item *
1505
77c8cf41
JH
1506$AUTOLOAD, sort(), lock(), and spawning subprocesses
1507in multiple threads simultaneously are now thread-safe.
f39f21d8
JH
1508
1509=item *
1510
77c8cf41 1511Allow read-only string on left hand side of non-modifying tr///.
f39f21d8 1512
77c8cf41 1513=item *
f39f21d8 1514
77c8cf41 1515Several Unicode fixes (but still not perfect).
f39f21d8 1516
77c8cf41 1517=over 8
f39f21d8
JH
1518
1519=item *
1520
77c8cf41
JH
1521BOMs (byte order marks) in the beginning of Perl files
1522(scripts, modules) should now be transparently skipped.
1523UTF-16 (UCS-2) encoded Perl files should now be read correctly.
f39f21d8
JH
1524
1525=item *
1526
77c8cf41 1527The character tables have been updated to Unicode 3.0.1.
f39f21d8
JH
1528
1529=item *
1530
77c8cf41
JH
1531chr() for values greater than 127 now create utf8 when under use
1532utf8.
f39f21d8 1533
77c8cf41 1534=item *
f39f21d8 1535
77c8cf41
JH
1536Comparing with utf8 data does not magically upgrade non-utf8 data into
1537utf8.
f39f21d8 1538
77c8cf41 1539=item *
f39f21d8 1540
77c8cf41 1541C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
f39f21d8 1542
77c8cf41 1543=item *
f39f21d8 1544
77c8cf41
JH
1545Concatenation with the C<.> operator or via variable interpolation,
1546C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
1547substitution with C<s///>, single-quoted UTF8, should now work--in
1548theory.
f39f21d8 1549
77c8cf41 1550=item *
f39f21d8 1551
77c8cf41
JH
1552The C<tr///> operator now works I<slightly> better but is still rather
1553broken. Note that the C<tr///CU> functionality has been removed (but
1554see pack('U0', ...)).
f39f21d8 1555
77c8cf41 1556=item *
f39f21d8 1557
77c8cf41 1558vec() now refuses to deal with characters >255.
f39f21d8 1559
77c8cf41 1560=item *
f39f21d8 1561
77c8cf41 1562Zero entries were missing from the Unicode classes like C<IsDigit>.
f39f21d8 1563
77c8cf41 1564=back
f39f21d8 1565
77c8cf41 1566=item *
f39f21d8 1567
77c8cf41
JH
1568UNIVERSAL::isa no longer caches methods incorrectly. (This broke
1569the Tk extension with 5.6.0.)
f39f21d8 1570
77c8cf41 1571=item *
f39f21d8 1572
77c8cf41
JH
1573Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
1574when building the Perl binary. The only exception to this is SunOS 4.x,
1575which needs them.
f39f21d8 1576
77c8cf41 1577=item *
f39f21d8 1578
77c8cf41 1579Some new Configure symbols, useful for extension writers:
f39f21d8 1580
77c8cf41 1581=over 8
f39f21d8 1582
77c8cf41 1583=item d_cmsghdr
f39f21d8 1584
77c8cf41 1585For struct cmsghdr.
f39f21d8 1586
77c8cf41 1587=item d_fcntl_can_lock
f39f21d8 1588
77c8cf41 1589Whether fcntl() can be used for file locking.
f39f21d8 1590
77c8cf41 1591=item d_fsync
f39f21d8 1592
77c8cf41 1593=item d_getitimer
f39f21d8 1594
77c8cf41 1595=item d_getpagsz
f39f21d8 1596
77c8cf41 1597For getpagesize(), though you should prefer POSIX::sysconf(_SC_PAGE_SIZE))
f39f21d8 1598
77c8cf41 1599=item d_msghdr_s
f39f21d8 1600
77c8cf41 1601For struct msghdr.
f39f21d8 1602
77c8cf41 1603=item need_va_copy
f39f21d8 1604
77c8cf41 1605Whether one needs to use Perl_va_copy() to copy varargs.
f39f21d8 1606
77c8cf41 1607=item d_readv
f39f21d8 1608
77c8cf41 1609=item d_recvmsg
f39f21d8 1610
77c8cf41 1611=item d_sendmsg
f39f21d8 1612
77c8cf41 1613=item sig_size
f39f21d8 1614
77c8cf41 1615The number of elements in an array needed to hold all the available signals.
f39f21d8 1616
77c8cf41 1617=item d_sockatmark
f39f21d8 1618
77c8cf41 1619=item d_strtoq
f39f21d8 1620
77c8cf41 1621=item d_u32align
f39f21d8 1622
77c8cf41 1623Whether one needs to access character data aligned by U32 sized pointers.
f39f21d8 1624
77c8cf41 1625=item d_ualarm
f39f21d8 1626
77c8cf41 1627=item d_usleep
f39f21d8 1628
77c8cf41 1629=back
f39f21d8 1630
77c8cf41 1631=item *
f39f21d8 1632
77c8cf41
JH
1633Removed Configure symbols: the PDP-11 memory model settings: huge,
1634large, medium, models.
f39f21d8 1635
77c8cf41 1636=item *
f39f21d8 1637
77c8cf41 1638SOCKS support is now much more robust.
f39f21d8 1639
77c8cf41 1640=item *
f39f21d8 1641
77c8cf41
JH
1642If your file system supports symbolic links you can build Perl outside
1643of the source directory by
f39f21d8 1644
77c8cf41
JH
1645 mkdir /tmp/perl/build/directory
1646 cd /tmp/perl/build/directory
1647 sh /path/to/perl/source/Configure -Dmksymlinks ...
f39f21d8 1648
77c8cf41
JH
1649This will create in /tmp/perl/build/directory a tree of symbolic links
1650pointing to files in /path/to/perl/source. The original files are left
1651unaffected. After Configure has finished you can just say
f39f21d8 1652
77c8cf41 1653 make all test
f39f21d8 1654
77c8cf41 1655and Perl will be built and tested, all in /tmp/perl/build/directory.
f39f21d8 1656
77c8cf41 1657=back
f39f21d8 1658
77c8cf41 1659=head2 Platform Specific Changes and Fixes
f39f21d8
JH
1660
1661=over 4
1662
1663=item *
1664
77c8cf41 1665BSDI 4.*
f39f21d8 1666
77c8cf41 1667Perl now works on post-4.0 BSD/OSes.
f39f21d8
JH
1668
1669=item *
1670
77c8cf41 1671All BSDs
f39f21d8 1672
77c8cf41 1673Setting C<$0> now works (as much as possible; see perlvar for details).
f39f21d8
JH
1674
1675=item *
1676
77c8cf41 1677Cygwin
f39f21d8 1678
77c8cf41 1679Numerous updates; currently synchronised with Cygwin 1.1.4.
f39f21d8
JH
1680
1681=item *
1682
77c8cf41 1683EPOC
f39f21d8 1684
77c8cf41 1685EPOC update after Perl 5.6.0. See README.epoc.
f39f21d8
JH
1686
1687=item *
1688
77c8cf41 1689FreeBSD 3.*
f39f21d8 1690
77c8cf41 1691Perl now works on post-3.0 FreeBSDs.
f39f21d8
JH
1692
1693=item *
1694
77c8cf41
JH
1695HP-UX
1696
1697README.hpux updated; C<Configure -Duse64bitall> now almost works.
f39f21d8
JH
1698
1699=item *
1700
77c8cf41 1701IRIX
f39f21d8 1702
77c8cf41
JH
1703Numerous compilation flag and hint enhancements; accidental mixing
1704of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
f39f21d8 1705
77c8cf41 1706=item *
f39f21d8 1707
77c8cf41 1708Linux
f39f21d8 1709
77c8cf41 1710Long doubles should now work (see INSTALL).
f39f21d8
JH
1711
1712=item *
1713
77c8cf41 1714MacOS Classic
f39f21d8 1715
77c8cf41
JH
1716Compilation of the standard Perl distribution in MacOS Classic should
1717now work if you have the Metrowerks development environment and
1718the missing Mac-specific toolkit bits. Contact the macperl mailing
1719list for details.
f39f21d8
JH
1720
1721=item *
1722
77c8cf41 1723MPE/iX
f39f21d8 1724
77c8cf41 1725MPE/iX update after Perl 5.6.0. See README.mpeix.
f39f21d8
JH
1726
1727=item *
1728
77c8cf41 1729NetBSD/sparc
f39f21d8 1730
77c8cf41 1731Perl now works on NetBSD/sparc.
f39f21d8
JH
1732
1733=item *
1734
77c8cf41 1735OS/2
f39f21d8 1736
77c8cf41 1737Now works with usethreads (see INSTALL).
f39f21d8
JH
1738
1739=item *
1740
77c8cf41 1741Solaris
f39f21d8 1742
77c8cf41 174364-bitness using the Sun Workshop compiler now works.
f39f21d8
JH
1744
1745=item *
1746
77c8cf41 1747Tru64 (aka Digital UNIX, aka DEC OSF/1)
f39f21d8 1748
77c8cf41
JH
1749The operating system version letter now recorded in $Config{osvers}.
1750Allow compiling with gcc (previously explicitly forbidden). Compiling
1751with gcc still not recommended because buggy code results, even with
1752gcc 2.95.2.
f39f21d8
JH
1753
1754=item *
1755
77c8cf41
JH
1756Unicos
1757
1758Fixed various alignment problems that lead into core dumps either
1759during build or later; no longer dies on math errors at runtime;
1760now using full quad integers (64 bits), previously was using
1761only 46 bit integers for speed.
f39f21d8
JH
1762
1763=item *
1764
77c8cf41
JH
1765VMS
1766
1767chdir() now works better despite a CRT bug; now works with MULTIPLICITY
1768(see INSTALL); now works with Perl's malloc.
f39f21d8
JH
1769
1770=item *
1771
77c8cf41 1772Windows
f39f21d8 1773
77c8cf41 1774=over 8
f39f21d8
JH
1775
1776=item *
1777
77c8cf41 1778accept() no longer leaks memory.
f39f21d8
JH
1779
1780=item *
1781
77c8cf41 1782Better chdir() return value for a non-existent directory.
f39f21d8 1783
77c8cf41 1784=item *
f39f21d8 1785
77c8cf41 1786New %ENV entries now propagate to subprocesses.
f39f21d8
JH
1787
1788=item *
1789
77c8cf41
JH
1790$ENV{LIB} now used to search for libs under Visual C.
1791
1792=item *
1793
1794A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
f39f21d8
JH
1795
1796=item *
1797
77c8cf41 1798Allow REG_EXPAND_SZ keys in the registry.
f39f21d8
JH
1799
1800=item *
1801
77c8cf41 1802Can now send() from all threads, not just the first one.
f39f21d8
JH
1803
1804=item *
1805
77c8cf41 1806Fake signal handling reenabled, bugs and all.
f39f21d8
JH
1807
1808=item *
1809
77c8cf41
JH
1810Less stack reserved per thread so that more threads can run
1811concurrently. (Still 16M per thread.)
f39f21d8
JH
1812
1813=item *
1814
77c8cf41
JH
1815C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
1816(works better when perl is running as service).
f39f21d8
JH
1817
1818=item *
1819
77c8cf41 1820Better UNC path handling under ithreads.
f39f21d8
JH
1821
1822=item *
1823
77c8cf41 1824wait() and waitpid() now work much better.
f39f21d8
JH
1825
1826=item *
1827
77c8cf41 1828winsock handle leak fixed.
f39f21d8
JH
1829
1830=back
1831
77c8cf41 1832=back
f39f21d8 1833
77c8cf41 1834=head1 New or Changed Diagnostics
f39f21d8 1835
77c8cf41
JH
1836All regular expression compilation error messages are now hopefully
1837easier to understand both because the error message now comes before
1838the failed regex and because the point of failure is now clearly
1839marked.
f39f21d8 1840
77c8cf41
JH
1841The various "opened only for", "on closed", "never opened" warnings
1842drop the C<main::> prefix for filehandles in the C<main> package,
1843for example C<STDIN> instead of <main::STDIN>.
f39f21d8 1844
77c8cf41
JH
1845The "Unrecognized escape" warning has been extended to include C<\8>,
1846C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
f39f21d8 1847
77c8cf41 1848=over 4
f39f21d8 1849
77c8cf41
JH
1850Two new debugging options have been added: if you have compiled your
1851Perl with debugging, you can use the -DT and -DR options to trace
1852tokenising and to add reference counts to displaying variables,
1853respectively.
f39f21d8
JH
1854
1855=item *
1856
77c8cf41
JH
1857If an attempt to use a (non-blessed) reference as an array index
1858is made, a warning is given.
f39f21d8
JH
1859
1860=item *
1861
77c8cf41
JH
1862C<push @a;> and C<unshift @a;> (with no values to push or unshift)
1863now give a warning. This may be a problem for generated and evaled
1864code.
f39f21d8
JH
1865
1866=back
1867
77c8cf41 1868=head1 Changed Internals
f39f21d8
JH
1869
1870=over 4
1871
1872=item *
1873
77c8cf41
JH
1874perlapi.pod (a companion to perlguts) now attempts to document the
1875internal API.
f39f21d8
JH
1876
1877=item *
1878
77c8cf41
JH
1879You can now build a really minimal perl called microperl.
1880Building microperl does not require even running Configure;
1881C<make -f Makefile.micro> should be enough. Beware: microperl makes
1882many assumptions, some of which may be too bold; the resulting
1883executable may crash or otherwise misbehave in wondrous ways.
1884For careful hackers only.
f39f21d8
JH
1885
1886=item *
1887
77c8cf41 1888Added rsignal(), whichsig(), do_join() to the publicised API.
f39f21d8
JH
1889
1890=item *
1891
77c8cf41 1892Made possible to propagate customised exceptions via croak()ing.
f39f21d8 1893
77c8cf41 1894=item *
f39f21d8 1895
77c8cf41 1896Added is_utf8_char(), is_utf8_string(), bytes_to_utf8(), and utf8_to_bytes().
f39f21d8 1897
77c8cf41 1898=item *
f39f21d8 1899
77c8cf41 1900Now xsubs can have attributes just like subs.
f39f21d8
JH
1901
1902=item *
1903
77c8cf41
JH
1904Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv().
1905For the full list of the available APIs see L<perlapi>.
f39f21d8
JH
1906
1907=item *
1908
77c8cf41
JH
1909dTHR and djSP have been obsoleted; the former removed (because it's
1910a no-op) and the latter replaced with dSP.
f39f21d8
JH
1911
1912=item *
1913
77c8cf41
JH
1914Perl now uses system malloc instead of Perl malloc on all 64-bit
1915platforms, and even in some not-always-64-bit platforms like AIX,
1916IRIX, and Solaris. This change breaks backward compatibility but
1917Perl's malloc has problems with large address spaces and also the
1918speed of vendors' malloc is generally better in large address space
1919machines (Perl's malloc is mostly tuned for space).
f39f21d8 1920
888aee59
JH
1921=item *
1922
1923PERL_OBJECT has been completely removed.
1924
77c8cf41 1925=back
f39f21d8 1926
77c8cf41 1927=head1 Security Vulnerability Closed
f39f21d8 1928
77c8cf41 1929(This change was already made in 5.7.0 but bears repeating here.)
f39f21d8 1930
77c8cf41
JH
1931A potential security vulnerability in the optional suidperl component
1932of Perl was identified in August 2000. suidperl is neither built nor
1933installed by default. As of November 2001 the only known vulnerable
1934platform is Linux, most likely all Linux distributions. CERT and
1935various vendors and distributors have been alerted about the vulnerability.
1936See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
1937for more information.
f39f21d8 1938
77c8cf41
JH
1939The problem was caused by Perl trying to report a suspected security
1940exploit attempt using an external program, /bin/mail. On Linux
1941platforms the /bin/mail program had an undocumented feature which
1942when combined with suidperl gave access to a root shell, resulting in
1943a serious compromise instead of reporting the exploit attempt. If you
1944don't have /bin/mail, or if you have 'safe setuid scripts', or if
1945suidperl is not installed, you are safe.
f39f21d8 1946
77c8cf41
JH
1947The exploit attempt reporting feature has been completely removed from
1948Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
1949from all the Perl 5.7 releases), so that particular vulnerability
1950isn't there anymore. However, further security vulnerabilities are,
1951unfortunately, always possible. The suidperl code is being reviewed
1952and if deemed too risky to continue to be supported, it may be
1953completely removed from future releases. In any case, suidperl should
1954only be used by security experts who know exactly what they are doing
1955and why they are using suidperl instead of some other solution such as
1956sudo (see http://www.courtesan.com/sudo/).
f39f21d8 1957
77c8cf41 1958=head1 Selected Bug Fixes
f39f21d8 1959
77c8cf41
JH
1960Numerous memory leaks and uninitialized memory accesses have been hunted down.
1961Most importantly anonymous subs used to leak quite a bit.
1962
1963=over 4
f39f21d8
JH
1964
1965=item *
1966
77c8cf41
JH
1967chop(@list) in list context returned the characters chopped in
1968reverse order. This has been reversed to be in the right order.
f39f21d8 1969
77c8cf41 1970=item *
f39f21d8 1971
77c8cf41 1972The order of DESTROYs has been made more predictable.
f39f21d8 1973
77c8cf41
JH
1974=item *
1975
1976mkdir() now ignores trailing slashes in the directory name,
1977as mandated by POSIX.
f39f21d8
JH
1978
1979=item *
1980
77c8cf41 1981Attributes (like :shared) didn't work with our().
f39f21d8
JH
1982
1983=item *
1984
77c8cf41
JH
1985The PERL5OPT environment variable (for passing command line arguments
1986to Perl) didn't work for more than a single group of options.
f39f21d8
JH
1987
1988=item *
1989
77c8cf41
JH
1990The tainting behaviour of sprintf() has been rationalized. It does
1991not taint the result of floating point formats anymore, making the
1992behaviour consistent with that of string interpolation.
f39f21d8
JH
1993
1994=item *
1995
77c8cf41 1996All but the first argument of the IO syswrite() method are now optional.
f39f21d8 1997
77c8cf41 1998=item *
f39f21d8 1999
77c8cf41
JH
2000Tie::ARRAY SPLICE method was broken.
2001
2002=item *
f39f21d8 2003
77c8cf41
JH
2004vec() now tries to work with characters <= 255 when possible, but it leaves
2005higher character values in place. In that case, if vec() was used to modify
2006the string, it is no longer considered to be utf8-encoded.
f39f21d8
JH
2007
2008=item *
2009
2010The autouse pragma didn't work for Multi::Part::Function::Names.
2011
2012=item *
2013
2014The behaviour of non-decimal but numeric string constants such as
2015"0x23" was platform-dependent: in some platforms that was seen as 35,
2016in some as 0, in some as a floating point number (don't ask). This
2017was caused by Perl using the operating system libraries in a situation
2018where the result of the string to number conversion is undefined: now
2019Perl consistently handles such strings as zero in numeric contexts.
2020
2021=item *
2022
2023L<dprofpp> -R didn't work.
2024
2025=item *
2026
2027PERL5OPT with embedded spaces didn't work.
2028
2029=item *
2030
2031L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
2032
2033=back
2034
2035=head2 Platform Specific Changes and Fixes
2036
2037=over 4
2038
2039=item *
2040
2041Some versions of glibc have a broken modfl(). This affects builds
2042with C<-Duselongdouble>. This version of Perl detects this brokenness
2043and has a workaround for it. The glibc release 2.2.2 is known to have
2044fixed the modfl() bug.
2045
2046=back
2047
77c8cf41
JH
2048=head2 Platform Specific Changes and Fixes
2049
2050=over 4
2051
2052=item *
2053
2054Linux previously had problems related to sockaddrlen when using
2055accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
2056
2057=item *
2058
2059Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
2060
2061=item *
2062
2063Windows
2064
2065=over 8
2066
2067=item *
2068
2069Borland C++ v5.5 is now a supported compiler that can build Perl.
2070However, the generated binaries continue to be incompatible with those
2071generated by the other supported compilers (GCC and Visual C++).
2072
2073=item *
2074
2075Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
2076Other bugs in chdir() and Cwd::cwd() have also been fixed.
2077
2078=item *
2079
2080Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
2081
2082=item *
2083
2084HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
2085
2086=item *
2087
2088The makefiles now provide a single switch to bulk-enable all the features
2089enabled in ActiveState ActivePerl (a popular binary distribution).
2090
2091=back
2092
2093=head1 New Tests
2094
2095Several new tests have been added, especially for the F<lib> subsection.
2096
2097The tests are now reported in a different order than in earlier Perls.
2098(This happens because the test scripts from under t/lib have been moved
2099to be closer to the library/extension they are testing.)
2100
f39f21d8
JH
2101=head1 New or Changed Diagnostics
2102
2103=over 4
2104
2105=item *
2106
2107In the regular expression diagnostics the C<E<lt>E<lt> HERE> marker
2108introduced in 5.7.0 has been changed to be C<E<lt>-- HERE> since too
2109many people found the C<E<lt>E<lt>> to be too similar to here-document
2110starters.
2111
2112=item *
2113
2114If you try to L<perlfunc/pack> a number less than 0 or larger than 255
2115using the C<"C"> format you will get an optional warning. Similarly
2116for the C<"c"> format and a number less than -128 or more than 127.
2117
2118=item *
2119
2120Certain regex modifiers such as C<(?o)> make sense only if applied to
2121the entire regex. You will an optional warning if you try to do otherwise.
2122
2123=item *
2124
2125Using arrays or hashes as references (e.g. C<%foo->{bar}> has been
2126deprecated for a while. Now you will get an optional warning.
2127
2128=back
2129
2130=head1 Source Code Enhancements
2131
2132=head2 MAGIC constants
2133
2134The MAGIC constants (e.g. C<'P'>) have been macrofied
2135(e.g. C<PERL_MAGIC_TIED>) for better source code readability
2136and maintainability.
2137
2138=head2 Better commented code
2139
2140F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
2141
2142=head2 Regex pre-/post-compilation items matched up
2143
2144The regex compiler now maintains a structure that identifies nodes in
2145the compiled bytecode with the corresponding syntactic features of the
2146original regex expression. The information is attached to the new
2147C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
2148complete information.
2149
2150=head2 gcc -Wall
2151
2152The C code has been made much more C<gcc -Wall> clean. Some warning
2153messages still remain, though, so if you are compiling with gcc you
2154will see some warnings about dubious practices. The warnings are
2155being worked on.
2156
f39f21d8
JH
2157=head1 Known Problems
2158
2159Note that unlike other sections in this document (which describe
2160changes since 5.7.0) this section is cumulative containing known
2161problems for all the 5.7 releases.
2162
2163=head2 AIX
2164
2165=over 4
2166
2167=item *
2168
2169In AIX 4.2 Perl extensions that use C++ functions that use statics
2170may have problems in that the statics are not getting initialized.
2171In newer AIX releases this has been solved by linking Perl with
2172the libC_r library, but unfortunately in AIX 4.2 the said library
2173has an obscure bug where the various functions related to time
2174(such as time() and gettimeofday()) return broken values, and
2175therefore in AIX 4.2 Perl is not linked against the libC_r.
2176
2177=item *
2178
2179vac 5.0.0.0 May Produce Buggy Code For Perl
2180
2181The AIX C compiler vac version 5.0.0.0 may produce buggy code,
2182resulting in few random tests failing, but when the failing tests
2183are run by hand, they succeed. We suggest upgrading to at least
2184vac version 5.0.1.0, that has been known to compile Perl correctly.
2185"lslpp -L|grep vac.C" will tell you the vac version.
2186
2187=back
2188
2189=head2 Amiga Perl Invoking Mystery
2190
2191One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
2192works, but for example C<bin:perl -v> doesn't. The exact reason is
2193known but the current suspect is the F<ixemul> library.
2194
2195=head2 lib/ftmp-security tests warn 'system possibly insecure'
2196
2197Don't panic. Read INSTALL 'make test' section instead.
2198
2199=head2 Cygwin intermittent failures of lib/Memoize/t/expire_file 11 and 12
2200
2201The subtests 11 and 12 sometimes fail and sometimes work.
2202
2203=head2 HP-UX lib/io_multihomed Fails When LP64-Configured
2204
2205The lib/io_multihomed test may hang in HP-UX if Perl has been
2206configured to be 64-bit. Because other 64-bit platforms do not hang in
2207this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
2208test attempts to create and connect to "multihomed" sockets (sockets
2209which have multiple IP addresses).
2210
2211=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
2212
2213If perl is configured with -Duse64bitall, the successful result of the
2214subtest 10 of lib/posix may arrive before the successful result of the
2215subtest 9, which confuses the test harness so much that it thinks the
2216subtest 9 failed.
2217
2218=head2 Linux With Sfio Fails op/misc Test 48
2219
2220No known fix.
2221
2222=head2 OS/390
2223
2224OS/390 has rather many test failures but the situation is actually
2225better than it was in 5.6.0, it's just that so many new modules and
2226tests have been added.
2227
2228 Failed Test Stat Wstat Total Fail Failed List of Failed
2229 -----------------------------------------------------------------------------
2230 ../ext/B/Deparse.t 14 1 7.14% 14
2231 ../ext/B/Showlex.t 1 1 100.00% 1
2232 ../ext/Encode/Encode/Tcl.t 610 13 2.13% 592 594 596 598
2233 600 602 604-610
2234 ../ext/IO/lib/IO/t/io_unix.t 113 28928 5 3 60.00% 3-5
2235 ../ext/POSIX/POSIX.t 29 1 3.45% 14
2236 ../ext/Storable/t/lock.t 255 65280 5 3 60.00% 3-5
2237 ../lib/locale.t 129 33024 117 19 16.24% 99-117
2238 ../lib/warnings.t 434 1 0.23% 75
2239 ../lib/ExtUtils.t 27 1 3.70% 25
2240 ../lib/Math/BigInt/t/bigintpm.t 1190 1 0.08% 1145
2241 ../lib/Unicode/UCD.t 81 48 59.26% 1-16 49-64 66-81
2242 ../lib/User/pwent.t 9 1 11.11% 4
2243 op/pat.t 660 6 0.91% 242-243 424-425
2244 626-627
2245 op/split.t 0 9 ?? ?? % ??
2246 op/taint.t 174 3 1.72% 156 162 168
2247 op/tr.t 70 3 4.29% 50 58-59
2248 Failed 16/422 test scripts, 96.21% okay. 105/23251 subtests failed, 99.55% okay.
2249
2250=head2 op/sprintf tests 129 and 130
2251
2252The op/sprintf tests 129 and 130 are known to fail on some platforms.
2253Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
2254The failing platforms do not comply with the ANSI C Standard, line
225519ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
2256something other than "1" and "-1" when formatting 0.6 and -0.6 using
2257the printf format "%.0f", most often they produce "0" and "-0".)
2258
2259=head2 Failure of Thread tests
2260
2261B<Note that support for 5.005-style threading remains experimental.>
2262
2263The following tests are known to fail due to fundamental problems in
2264the 5.005 threading implementation. These are not new failures--Perl
22655.005_0x has the same bugs, but didn't have these tests.
2266
2267 lib/autouse.t 4
2268 t/lib/thr5005.t 19-20
2269
2270=head2 UNICOS
2271
2272=over 4
2273
2274=item *
2275
2276ext/POSIX/sigaction subtests 6 and 13 may fail.
2277
2278=item *
2279
2280lib/ExtUtils may spuriously claim that subtest 28 failed,
2281which is interesting since the test only has 27 tests.
2282
2283=item *
2284
2285Numerous numerical test failures
2286
2287 op/numconvert 209,210,217,218
2288 op/override 7
2289 ext/Time/HiRes/HiRes 9
2290 lib/Math/BigInt/t/bigintpm 1145
2291 lib/Math/Trig 25
2292
2293These tests fail because of yet unresolved floating point inaccuracies.
2294
2295=back
2296
2297=head2 UTS
2298
2299There are a few known test failures, see L<perluts>.
2300
2301=head2 VMS
2302
2303Rather many tests are failing in VMS but that actually more tests
2304succeed in VMS than they used to, it's just that there are many,
2305many more tests than there used to be.
2306
2307Here are the known failures from some compiler/platform combinations.
2308
2309DEC C V5.3-006 on OpenVMS VAX V6.2
2310
2311 [-.ext.list.util.t]tainted..............FAILED on test 3
2312 [-.ext.posix]sigaction..................FAILED on test 7
2313 [-.ext.time.hires]hires.................FAILED on test 14
2314 [-.lib.file.find]taint..................FAILED on test 17
2315 [-.lib.math.bigint.t]bigintpm...........FAILED on test 1183
2316 [-.lib.test.simple.t]exit...............FAILED on test 1
2317 [.lib]vmsish............................FAILED on test 13
2318 [.op]sprintf............................FAILED on test 12
2319 Failed 8/399 tests, 91.23% okay.
2320
2321DEC C V6.0-001 on OpenVMS Alpha V7.2-1 and
2322Compaq C V6.2-008 on OpenVMS Alpha V7.1
2323
2324 [-.ext.list.util.t]tainted..............FAILED on test 3
2325 [-.lib.file.find]taint..................FAILED on test 17
2326 [-.lib.test.simple.t]exit...............FAILED on test 1
2327 [.lib]vmsish............................FAILED on test 13
2328 Failed 4/399 tests, 92.48% okay.
2329
2330Compaq C V6.4-005 on OpenVMS Alpha 7.2.1
2331
2332 [-.ext.b]showlex........................FAILED on test 1
2333 [-.ext.list.util.t]tainted..............FAILED on test 3
2334 [-.lib.file.find]taint..................FAILED on test 17
2335 [-.lib.test.simple.t]exit...............FAILED on test 1
2336 [.lib]vmsish............................FAILED on test 13
2337 [.op]misc...............................FAILED on test 49
2338 Failed 6/401 tests, 92.77% okay.
2339
2340=head2 Win32
2341
2342In multi-CPU boxes there are some problems with the I/O buffering:
2343some output may appear twice.
2344
2345=head2 Localising a Tied Variable Leaks Memory
2346
2347 use Tie::Hash;
2348 tie my %tie_hash => 'Tie::StdHash';
2349
2350 ...
2351
2352 local($tie_hash{Foo}) = 1; # leaks
2353
2354Code like the above is known to leak memory every time the local()
2355is executed.
2356
2357=head2 Self-tying of Arrays and Hashes Is Forbidden
2358
2359Self-tying of arrays and hashes is broken in rather deep and
2360hard-to-fix ways. As a stop-gap measure to avoid people from getting
2361frustrated at the mysterious results (core dumps, most often) it is
2362for now forbidden (you will get a fatal error even from an attempt).
2363
2364=head2 Variable Attributes are not Currently Usable for Tieing
2365
2366This limitation will hopefully be fixed in future. (Subroutine
2367attributes work fine for tieing, see L<Attribute::Handlers>).
2368
2369=head2 Building Extensions Can Fail Because Of Largefiles
2370
2371Some extensions like mod_perl are known to have issues with
2372`largefiles', a change brought by Perl 5.6.0 in which file offsets
2373default to 64 bits wide, where supported. Modules may fail to compile
2374at all or compile and work incorrectly. Currently there is no good
2375solution for the problem, but Configure now provides appropriate
2376non-largefile ccflags, ldflags, libswanted, and libs in the %Config
2377hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
2378having problems can try configuring themselves without the
2379largefileness. This is admittedly not a clean solution, and the
2380solution may not even work at all. One potential failure is whether
2381one can (or, if one can, whether it's a good idea) link together at
2382all binaries with different ideas about file offsets, all this is
2383platform-dependent.
2384
2385=head2 The Compiler Suite Is Still Experimental
2386
2387The compiler suite is slowly getting better but is nowhere near
2388working order yet.
2389
2390=head2 The Long Double Support is Still Experimental
2391
2392The ability to configure Perl's numbers to use "long doubles",
2393floating point numbers of hopefully better accuracy, is still
2394experimental. The implementations of long doubles are not yet
2395widespread and the existing implementations are not quite mature
2396or standardised, therefore trying to support them is a rare
2397and moving target. The gain of more precision may also be offset
2398by slowdown in computations (more bits to move around, and the
2399operations are more likely to be executed by less optimised
2400libraries).
33a87e58 2401
cc0fca54
GS
2402=head1 Reporting Bugs
2403
d4ad863d
JH
2404If you find what you think is a bug, you might check the articles
2405recently posted to the comp.lang.perl.misc newsgroup and the perl
2406bug database at http://bugs.perl.org. There may also be
2407information at http://www.perl.com/perl/, the Perl Home Page.
cc0fca54
GS
2408
2409If you believe you have an unreported bug, please run the B<perlbug>
2410program included with your release. Be sure to trim your bug down
2411to a tiny but sufficient test case. Your bug report, along with the
d4ad863d 2412output of C<perl -V>, will be sent off to perlbug@perl.org to be
cc0fca54
GS
2413analysed by the Perl porting team.
2414
2415=head1 SEE ALSO
2416
2417The F<Changes> file for exhaustive details on what changed.
2418
2419The F<INSTALL> file for how to build Perl.
2420
2421The F<README> file for general stuff.
2422
2423The F<Artistic> and F<Copying> files for copyright information.
2424
2425=head1 HISTORY
2426
d468ca04 2427Written by Jarkko Hietaniemi <F<jhi@iki.fi>>.
cc0fca54
GS
2428
2429=cut