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ba370e9b 1=head1 NAME
cc0fca54 2
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
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12=head2 64-bit platforms and malloc
13
057b7f2b 14If your pointers are 64 bits wide, the Perl malloc is no longer being
c2e23569 15used because it does not work well with 8-byte pointers. Also,
61947107 16usually the system mallocs on such platforms are much better optimized
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17for such large memory models than the Perl malloc. Some memory-hungry
18Perl applications like the PDL don't work well with Perl's malloc.
19Finally, other applications than Perl (like modperl) tend to prefer
20the system malloc. Such platforms include Alpha and 64-bit HPPA,
21MIPS, PPC, and Sparc.
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22
23=head2 AIX Dynaloading
24
25The AIX dynaloading now uses in AIX releases 4.3 and newer the native
26dlopen interface of AIX instead of the old emulated interface. This
27change will probably break backward compatibility with compiled
28modules. The change was made to make Perl more compliant with other
29applications like modperl which are using the AIX native interface.
30
31=head2 Socket Extension Dynamic in VMS
32
33The Socket extension is now dynamically loaded instead of being
34statically built in. This may or may not be a problem with ancient
35TCP/IP stacks of VMS: we do not know since we weren't able to test
36Perl in such configurations.
37
38=head2 Different Definition of the Unicode Character Classes \p{In...}
39
40As suggested by the Unicode consortium, the Unicode character classes
41now prefer I<scripts> as opposed to I<blocks> (as defined by Unicode);
42in Perl, when the C<\p{In....}> and the C<\p{In....}> regular expression
43constructs are used. This has changed the definition of some of those
44character classes.
45
46The difference between scripts and blocks is that scripts are the
47glyphs used by a language or a group of languages, while the blocks
48are more artificial groupings of 256 characters based on the Unicode
49numbering.
50
51In general this change results in more inclusive Unicode character
52classes, but changes to the other direction also do take place:
53for example while the script C<Latin> includes all the Latin
54characters and their various diacritic-adorned versions, it
55does not include the various punctuation or digits (since they
56are not solely C<Latin>).
57
58Changes in the character class semantics may have happened if a script
59and a block happen to have the same name, for example C<Hebrew>.
60In such cases the script wins and C<\p{InHebrew}> now means the script
61definition of Hebrew. The block definition in still available,
62though, by appending C<Block> to the name: C<\p{InHebrewBlock}> means
63what C<\p{InHebrew}> meant in perl 5.6.0. For the full list
64of affected character classes, see L<perlunicode/Blocks>.
65
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66=head2 Perl Parser Stress Tested
67
68The Perl parser has been stress tested using both random input and
69Markov chain input and the few found crashes and lockups have been
70fixed.
71
c2e23569 72=head2 REF(...) Instead Of SCALAR(...)
77c8cf41 73
057b7f2b 74A reference to a reference now stringifies as "REF(0x81485ec)" instead
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75of "SCALAR(0x81485ec)" in order to be more consistent with the return
76value of ref().
77c8cf41 77
c2e23569 78=head2 Deprecations
77c8cf41 79
61947107 80=over 4
77c8cf41 81
61947107 82=item *
f39f21d8 83
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84The semantics of bless(REF, REF) were unclear and until someone proves
85it to make some sense, it is forbidden.
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86
87=item *
88
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89The obsolete chat2 library that should never have been allowed
90to escape the laboratory has been decommissioned.
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91
92=item *
93
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94The very dusty examples in the eg/ directory have been removed.
95Suggestions for new shiny examples welcome but the main issue is that
96the examples need to be documented, tested and (most importantly)
97maintained.
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98
99=item *
100
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101The (bogus) escape sequences \8 and \9 now give an optional warning
102("Unrecognized escape passed through"). There is no need to \-escape
103any C<\w> character.
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104
105=item *
106
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107The list of filenames from glob() (or <...>) is now by default sorted
108alphabetically to be csh-compliant. (bsd_glob() does still sort platform
109natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
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110
111=item *
112
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113Although "you shouldn't do that", it was possible to write code that
114depends on Perl's hashed key order (Data::Dumper does this). The new
115algorithm "One-at-a-Time" produces a different hashed key order.
116More details are in L</"Performance Enhancements">.
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117
118=item *
119
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120lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
121In future releases this may become a fatal error.
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122
123=item *
124
057b7f2b 125The C<package;> syntax (C<package> without an argument) has been
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126deprecated. Its semantics were never that clear and its
127implementation even less so. If you have used that feature to
128disallow all but fully qualified variables, C<use strict;> instead.
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129
130=item *
131
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132The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
133recognised but now cause fatal errors. The previous behaviour of
134ignoring them by default and warning if requested was unacceptable
135since it, in a way, falsely promised that the features could be used.
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136
137=item *
138
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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.
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146
147=item *
148
c2e23569 149The syntaxes C<< @a->[...] >> and C<< %h->{...}>> have now been deprecated.
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150
151=item *
152
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153After years of trying the suidperl is considered to be too complex to
154ever be considered truly secure. The suidperl functionality is likely
155to be removed in a future release.
156
157=item *
158
159The long deprecated uppercase aliases for the string comparison
160operators (EQ, NE, LT, LE, GE, GT) have now been removed.
161
162=item *
163
164The tr///C and tr///U features have been removed and will not return;
165the interface was a mistake. Sorry about that. For similar
166functionality, see pack('U0', ...) and pack('C0', ...).
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167
168=back
169
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170=head1 Core Enhancements
171
77c8cf41 172=head2 PerlIO is Now The Default
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173
174=over 4
175
176=item *
177
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178IO is now by default done via PerlIO rather than system's "stdio".
179PerlIO allows "layers" to be "pushed" onto a file handle to alter the
180handle's behaviour. Layers can be specified at open time via 3-arg
181form of open:
f39f21d8 182
77c8cf41 183 open($fh,'>:crlf :utf8', $path) || ...
f39f21d8 184
77c8cf41 185or on already opened handles via extended C<binmode>:
f39f21d8 186
77c8cf41 187 binmode($fh,':encoding(iso-8859-7)');
f39f21d8 188
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189The built-in layers are: unix (low level read/write), stdio (as in
190previous Perls), perlio (re-implementation of stdio buffering in a
191portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
192but available on any platform). A mmap layer may be available if
193platform supports it (mostly UNIXes).
f39f21d8 194
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195Layers to be applied by default may be specified via the 'open' pragma.
196
197See L</"Installation and Configuration Improvements"> for the effects
198of PerlIO on your architecture name.
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199
200=item *
201
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202File handles can be marked as accepting Perl's internal encoding of Unicode
203(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
f39f21d8 204
77c8cf41 205 open($fh,">:utf8","Uni.txt");
f39f21d8 206
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207Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
208for you since it's not UTF-8 what you will be getting but instead
209UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
210http://www.unicode.org/unicode/reports/tr16/ for more information.
211In future releases this naming may change.
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212
213=item *
214
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215File handles can translate character encodings from/to Perl's internal
216Unicode form on read/write via the ":encoding()" layer.
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217
218=item *
219
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220File handles can be opened to "in memory" files held in Perl scalars via:
221
222 open($fh,'>', \$variable) || ...
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223
224=item *
225
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226Anonymous temporary files are available without need to
227'use FileHandle' or other module via
f39f21d8 228
77c8cf41 229 open($fh,"+>", undef) || ...
f39f21d8 230
77c8cf41 231That is a literal undef, not an undefined value.
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232
233=item *
234
77c8cf41 235The list form of C<open> is now implemented for pipes (at least on UNIX):
f39f21d8 236
77c8cf41 237 open($fh,"-|", 'cat', '/etc/motd')
f39f21d8 238
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239creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
240the child process.
f39f21d8 241
e1f170bd 242=back
f39f21d8 243
e1f170bd 244=head2 Signals Are Now Safe
f39f21d8 245
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246Perl used to be fragile in that signals arriving at inopportune moments
247could corrupt Perl's internal state. Now Perl postpones handling of
248signals until it's safe.
f39f21d8 249
e1f170bd 250=head2 Unicode Overhaul
f39f21d8 251
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252Unicode in general should be now much more usable than in Perl 5.6.0
253(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
254regular expressions should work now, Unicode in tr/// should work now,
255Unicode in I/O should work now.
f39f21d8 256
e1f170bd 257=over 4
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258
259=item *
260
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261The Unicode Character Database coming with Perl has been upgraded
262to Unicode 3.1.1. For more information, see http://www.unicode.org/.
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263
264=item *
265
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266For developers interested in enhancing Perl's Unicode capabilities:
267almost all the UCD files are included with the Perl distribution in
e1f170bd 268the lib/unicore subdirectory. The most notable omission, for space
77c8cf41 269considerations, is the Unihan database.
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270
271=item *
272
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273The Unicode character classes \p{Blank} and \p{SpacePerl} have been
274added. "Blank" is like C isblank(), that is, it contains only
275"horizontal whitespace" (the space character is, the newline isn't),
276and the "SpacePerl" is the Unicode equivalent of C<\s> (\p{Space}
277isn't, since that includes the vertical tabulator character, whereas
278C<\s> doesn't.)
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279
280=back
281
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282=head2 Understanding of Numbers
283
284In general a lot of fixing has happened in the area of Perl's
285understanding of numbers, both integer and floating point. Since in
286many systems the standard number parsing functions like C<strtoul()>
287and C<atof()> seem to have bugs, Perl tries to work around their
288deficiencies. This results hopefully in more accurate numbers.
f39f21d8 289
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290Perl now tries internally to use integer values in numeric conversions
291and basic arithmetics (+ - * /) if the arguments are integers, and
292tries also to keep the results stored internally as integers.
057b7f2b 293This change leads to often slightly faster and always less lossy
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294arithmetics. (Previously Perl always preferred floating point numbers
295in its math.)
296
297=head2 Miscellaneous Enhancements
298
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299=over 4
300
301=item *
302
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303AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
304to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
305
306=item *
307
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308C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
309in multiple arguments.)
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310
311=item *
312
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313END blocks are now run even if you exit/die in a BEGIN block.
314Internally, the execution of END blocks is now controlled by
315PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
316behaviour for Perl embedders. This will default in 5.10. See
317L<perlembed>.
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318
319=item *
320
e1f170bd 321Formats now support zero-padded decimal fields.
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322
323=item *
324
77c8cf41 325Lvalue subroutines can now return C<undef> in list context.
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326
327=item *
328
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329A new special regular expression variable has been introduced:
330C<$^N>, which contains the most-recently closed group (submatch).
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331
332=item *
333
61947107 334C<no Module;> now works even if there is no "sub unimport" in the Module.
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335
336=item *
337
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338The numerical comparison operators return C<undef> if either operand
339is a NaN. Previously the behaviour was unspecified.
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340
341=item *
342
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343The following builtin functions are now overridable: each(), keys(),
344pop(), push(), shift(), splice(), unshift().
345
346=item *
347
61947107 348C<pack('U0a*', ...)> can now be used to force a string to UTF8.
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349
350=item *
351
61947107 352my __PACKAGE__ $obj now works.
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353
354=item *
355
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356The printf() and sprintf() now support parameter reordering using the
357C<%\d+\$> and C<*\d+\$> syntaxes. For example
358
359 print "%2\$s %1\$s\n", "foo", "bar";
360
361will print "bar foo\n"; This feature helps in writing
362internationalised software.
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363
364=item *
365
e1f170bd 366prototype(\&) is now available.
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367
368=item *
369
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370prototype(\[$@%&]) is now available to implicitly create references
371(useful for example if you want to emulate the tie() interface).
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372
373=item *
374
e1f170bd 375UNTIE method is now recognised.
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376
377=item *
378
379L<utime> now supports C<utime undef, undef, @files> to change the
380file timestamps to the current time.
381
382=item *
383
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384The rules for allowing underscores (underbars) in numeric constants
385have been relaxed and simplified: now you can have an underscore
386simply B<between digits>.
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387
388=back
389
77c8cf41 390=head1 Modules and Pragmata
f39f21d8 391
1e13d81f 392=head2 New Modules and Pragmata
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393
394=over 4
395
396=item *
397
61947107 398C<Attribute::Handlers> allows a class to define attribute handlers.
f39f21d8 399
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400 package MyPack;
401 use Attribute::Handlers;
402 sub Wolf :ATTR(SCALAR) { print "howl!\n" }
f39f21d8 403
61947107 404 # later, in some package using or inheriting from MyPack...
f39f21d8 405
61947107 406 my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
ba370e9b 407
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408Both variables and routines can have attribute handlers. Handlers can
409be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
410exact compilation phase (BEGIN, CHECK, INIT, or END).
f39f21d8 411
61947107 412=item *
f39f21d8 413
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414B<B::Concise> is a new compiler backend for walking the Perl syntax
415tree, printing concise info about ops, from Stephen McCamant. The
416output is highly customisable. See L<B::Concise>.
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417
418=item *
419
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420C<Class::ISA> for reporting the search path for a class's ISA tree,
421by Sean Burke, has been added. See L<Class::ISA>.
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422
423=item *
424
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425C<Cwd> has now a split personality: if possible, an XS extension is
426used, (this will hopefully be faster, more secure, and more robust)
427but if not possible, the familiar Perl implementation is used.
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428
429=item *
430
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431C<Devel::PPPort>, originally from Kenneth Albanowski and now
432maintained by Paul Marquess, has been added. It is primarily used
433by C<h2xs> to enhance portability of of XS modules between different
434versions of Perl.
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435
436=item *
437
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438C<Digest>, frontend module for calculating digests (checksums), from
439Gisle Aas, has been added. See L<Digest>.
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440
441=item *
442
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443C<Digest::MD5> for calculating MD5 digests (checksums) as defined in
444RFC 1321, from Gisle Aas, has been added. See L<Digest::MD5>.
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445
446 use Digest::MD5 'md5_hex';
447
448 $digest = md5_hex("Thirsty Camel");
449
450 print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
451
61947107 452NOTE: the C<MD5> backward compatibility module is deliberately not
e1f170bd 453included since its further use is discouraged.
f39f21d8 454
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455=item *
456
61947107 457C<Encode>, by Nick Ing-Simmons, provides a mechanism to translate
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458between different character encodings. Support for Unicode,
459ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
460compiled in to the module. Several other encodings (like Japanese,
461Chinese, and MacIntosh encodings) are included and will be loaded at
61947107 462runtime. See L<Encode>.
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463
464Any encoding supported by Encode module is also available to the
465":encoding()" layer if PerlIO is used.
466
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467=item *
468
469C<I18N::Langinfo> can be use to query locale information.
470See L<I18N::Langinfo>.
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471
472=item *
473
61947107 474C<I18N::LangTags> has functions for dealing with RFC3066-style
bea4d472 475language tags, by Sean Burke. See L<I18N::LangTags>.
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476
477=item *
478
479C<ExtUtils::Constant> is a new tool for extension writers for
480generating XS code to import C header constants, by Nicholas Clark.
481See L<ExtUtils::Constant>.
482
483=item *
484
485C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
486from Damian Conway. See L<Filter::Simple>.
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487
488 # in MyFilter.pm:
489
490 package MyFilter;
491
492 use Filter::Simple sub {
493 while (my ($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
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511=item *
512
513C<File::Temp> allows one to create temporary files and directories in
514an easy, portable, and secure way, by Tim Jenness. See L<File::Temp>.
515
516=item *
517
518C<Filter::Util::Call> provides you with the framework to write
519I<Source Filters> in Perl, from Paul Marquess. For most uses the
520frontend Filter::Simple is to be preferred. See L<Filter::Util::Call>.
521
522=item *
523
524L<libnet> is a collection of perl5 modules related to network
525programming, from Graham Barr. See L<Net::FTP>, L<Net::NNTP>,
526L<Net::Ping>, L<Net::POP3>, L<Net::SMTP>, and L<Net::Time>.
527
528Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
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529
530=item *
531
61947107 532C<List::Util> is a selection of general-utility list subroutines, like
bea4d472 533sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
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534
535=item *
536
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537C<Locale::Constants>, C<Locale::Country>, C<Locale::Currency>, and
538C<Locale::Language>, from Neil Bowers, have been added. They provide the
539codes for various locale standards, such as "fr" for France, "usd" for
540US Dollar, and "jp" for Japanese.
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541
542 use Locale::Country;
543
544 $country = code2country('jp'); # $country gets 'Japan'
545 $code = country2code('Norway'); # $code gets 'no'
546
547See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
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548and L<Locale::Language>.
549
550=item *
551
552C<Locale::Maketext> is localization framework from Sean Burke. See
553L<Locale::Maketext>, and L<Locale::Maketext::TPJ13>. The latter is an
554article about software localization, originally published in The Perl
555Journal #13, republished here with kind permission.
556
557=item *
558
559C<Memoize> can make your functions faster by trading space for time,
560from Mark-Jason Dominus. See L<Memoize>.
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561
562=item *
563
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564C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
565as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
566Extensions)>.
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567
568 use MIME::Base64;
569
570 $encoded = encode_base64('Aladdin:open sesame');
571 $decoded = decode_base64($encoded);
572
573 print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
574
61947107 575See L<MIME::Base64>.
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576
577=item *
578
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579C<MIME::QuotedPrint> allows you to encode data in quoted-printable
580encoding, as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
581Extensions)>, from Gisle Aas.
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582
583 use MIME::QuotedPrint;
584
585 $encoded = encode_qp("Smiley in Unicode: \x{263a}");
586 $decoded = decode_qp($encoded);
587
588 print $encoded, "\n"; # "Smiley in Unicode: =263A"
589
590MIME::QuotedPrint has been enhanced to provide the basic methods
591necessary to use it with PerlIO::Via as in :
592
593 use MIME::QuotedPrint;
057b7f2b 594 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8 595
61947107 596See L<MIME::QuotedPrint>.
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597
598=item *
599
61947107
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600C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
601See L<NEXT>.
f39f21d8
JH
602
603=item *
604
1e13d81f
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605C<open> is a new pragma for setting the default I/O disciplines
606for open().
607
608=item *
609
61947107
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610C<PerlIO::Scalar> provides the implementation of IO to "in memory"
611Perl scalars as discussed above, from Nick Ing-Simmons. It also
612serves as an example of a loadable PerlIO layer. Other future
613possibilities include PerlIO::Array and PerlIO::Code.
614See L<PerlIO::Scalar>.
615
616=item *
617
618C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
619functionality provided by a class (typically implemented in perl
620code), from Nick Ing-Simmons.
f39f21d8
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621
622 use MIME::QuotedPrint;
057b7f2b 623 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8
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624
625This will automatically convert everything output to C<$fh>
61947107 626to Quoted-Printable. See L<PerlIO::Via>.
f39f21d8
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627
628=item *
629
1e13d81f 630C<Pod::ParseLink>, by Russ Allbery, has been added,
e1f170bd 631to parse L&lt;&gt; links in pods as described in the new
1e13d81f
JH
632perlpodspec.
633
634=item *
635
61947107 636C<Pod::Text::Overstrike>, by Joe Smith, has been added.
f39f21d8 637It converts POD data to formatted overstrike text.
61947107 638See L<Pod::Text::Overstrike>.
f39f21d8
JH
639
640=item *
641
61947107
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642C<Scalar::Util> is a selection of general-utility scalar subroutines,
643like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
644
645=item *
646
1e13d81f
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647C<sort> is a new pragma for controlling the behaviour of sort().
648
649=item *
650
61947107
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651C<Storable> gives persistence to Perl data structures by allowing the
652storage and retrieval of Perl data to and from files in a fast and
653compact binary format, from Raphael Manfredi. See L<Storable>.
654
655=item *
656
657C<Switch>, from Damian Conway, has been added. Just by saying
f39f21d8
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658
659 use Switch;
660
661you have C<switch> and C<case> available in Perl.
662
663 use Switch;
664
665 switch ($val) {
666
667 case 1 { print "number 1" }
668 case "a" { print "string a" }
669 case [1..10,42] { print "number in list" }
670 case (@array) { print "number in list" }
671 case /\w+/ { print "pattern" }
672 case qr/\w+/ { print "pattern" }
673 case (%hash) { print "entry in hash" }
674 case (\%hash) { print "entry in hash" }
675 case (\&sub) { print "arg to subroutine" }
676 else { print "previous case not true" }
677 }
678
61947107
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679See L<Switch>.
680
681=item *
682
683C<Test::More> is yet another framework for writing test scripts,
684more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
685
686=item *
687
688C<Test::Simple> has the- basic utilities for writing tests, by Michael
689Schwern. See L<Test::Simple>.
77c8cf41
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690
691=item *
692
61947107
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693C<Text::Balanced> has been added, for extracting delimited text
694sequences from strings, from Damian Conway.
77c8cf41
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695
696 use Text::Balanced 'extract_delimited';
697
698 ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
699
700$a will be "'never say never'", $b will be ', he never said'.
701
702In addition to extract_delimited() there are also extract_bracketed(),
703extract_quotelike(), extract_codeblock(), extract_variable(),
704extract_tagged(), extract_multiple(), gen_delimited_pat(), and
705gen_extract_tagged(). With these you can implement rather advanced
61947107 706parsing algorithms. See L<Text::Balanced>.
77c8cf41
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707
708=item *
709
c2e23569 710C<threads> is an interface to interpreter threads, by Arthur Bergman.
61947107 711Interpreter threads (ithreads) is the new thread model introduced in
c2e23569
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712Perl 5.6 but only available as an internal interface for extension
713writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
77c8cf41
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714
715=item *
716
61947107
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717C<threads::shared> allows data sharing for interpreter threads, from
718Arthur Bergman. In the ithreads model any data sharing between
719threads must be explicit, as opposed to the old 5.005 thread model
720where data sharing was implicit. See L<threads::shared>.
77c8cf41
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721
722=item *
723
61947107 724C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
ba370e9b
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725references (unlike the standard Tie::RefHash) The module is contained
726within Tie::RefHash, see L<Tie::RefHash>.
77c8cf41
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727
728=item *
729
61947107
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730C<Time::HiRes> provides high resolution timing (ualarm, usleep,
731and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
77c8cf41
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732
733=item *
734
61947107
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735C<Unicode::UCD> offers a querying interface to the Unicode Character
736Database. See L<Unicode::UCD>.
77c8cf41
JH
737
738=item *
739
61947107
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740C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
741for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
77c8cf41
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742
743=item *
744
61947107
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745C<Unicode::Normalize> implements the various Unicode normalization
746forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
77c8cf41
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747
748=item *
749
61947107
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750C<XS::Typemap>, by Tim Jenness, is a test extension that exercises XS
751typemaps. Nothing gets installed but for extension writers the code
752is worth studying.
77c8cf41
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753
754=back
755
756=head2 Updated And Improved Modules and Pragmata
757
758=over 4
759
760=item *
761
61947107
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762The following independently supported modules have been updated to the
763newest versions from CPAN: CGI, CPAN, DB_File, File::Spec, File::Temp,
764Getopt::Long, Math::BigFloat, Math::BigInt, the podlators bundle
765(Pod::Man, Pod::Text), Pod::LaTeX, Pod::Parser, Storable,
766Term::ANSIColor, Test, Text-Tabs+Wrap.
77c8cf41
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767
768=item *
769
61947107 770The attributes::reftype() now works on tied arguments.
77c8cf41
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771
772=item *
773
057b7f2b 774AutoLoader can now be disabled with C<no AutoLoader;>.
77c8cf41
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775
776=item *
777
1e13d81f
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778B::Deparse has been significantly enhanced. It now can deparse almost
779all of the standard test suite (so that the tests still succeed).
780There is a make target "test.deparse" for trying this out.
77c8cf41
JH
781
782=item *
783
1e13d81f 784Class::Struct can now define the classes in compile time.
77c8cf41
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785
786=item *
787
1e13d81f
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788Class::Struct now assigns the array/hash element if the accessor
789is called with an array/hash element as the B<sole> argument.
77c8cf41
JH
790
791=item *
792
1e13d81f 793Data::Dumper has now an option to sort hashes.
77c8cf41
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794
795=item *
796
1e13d81f
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797Data::Dumper has now an option to dump code references
798using B::Deparse.
77c8cf41
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799
800=item *
801
1e13d81f
JH
802The English module can now be used without the infamous performance
803hit by saying
77c8cf41 804
1e13d81f 805 use English '-no_performance_hit';
77c8cf41 806
1e13d81f
JH
807(Assuming, of course, that one doesn't need the troublesome variables
808C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
809C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
77c8cf41
JH
810
811=item *
812
1e13d81f
JH
813Fcntl, Socket, and Sys::Syslog have been rewritten to use the
814new-style constant dispatch section (see L<ExtUtils::Constant>).
815This means that they will be more robust and hopefully faster.
77c8cf41
JH
816
817=item *
818
1e13d81f
JH
819File::Find now has pre- and post-processing callbacks. It also
820correctly changes directories when chasing symbolic links. Callbacks
821(naughtily) exiting with "next;" instead of "return;" now work.
61947107
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822
823=item *
824
1e13d81f
JH
825File::Find is now (again) reentrant. It also has been made
826more portable.
77c8cf41 827
61947107
JH
828=item *
829
1e13d81f
JH
830File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
831prototype mismatch with CORE::glob().
61947107
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832
833=item *
834
835File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
836the returned list of filenames.
77c8cf41
JH
837
838=item *
839
840Devel::Peek now has an interface for the Perl memory statistics
841(this works only if you are using perl's malloc, and if you have
842compiled with debugging).
843
844=item *
845
1e13d81f
JH
846IPC::Open3 now allows the use of numeric file descriptors.
847
848=item *
849
77c8cf41
JH
850IO::Socket has now atmark() method, which returns true if the socket
851is positioned at the out-of-band mark. The method is also exportable
852as a sockatmark() function.
853
854=item *
855
856IO::Socket::INET has support for ReusePort option (if your platform
857supports it). The Reuse option now has an alias, ReuseAddr. For clarity
858you may want to prefer ReuseAddr.
859
860=item *
861
61947107
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862IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
863that the operating system will make one up.)
77c8cf41
JH
864
865=item *
866
1e13d81f
JH
867use lib now works identically to @INC. Removing directories
868with 'no lib' now works.
869
870=item *
871
872Math::BigFloat and Math::BigInt have undergone a full rewrite.
873They are now magnitudes faster, and they support various
61947107 874bignum libraries such as GMP and PARI as their backends.
f39f21d8
JH
875
876=item *
877
61947107
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878Net::Ping has been enhanced. There is now "external" protocol which
879uses Net::Ping::External module which runs external ping(1) and parses
880the output. An alpha version of Net::Ping::External is available in
881CPAN and in 5.7.2 the Net::Ping::External may be integrated to Perl.
f39f21d8 882
77c8cf41 883=item *
f39f21d8 884
c2e23569 885C<POSIX::sigaction()> is now much more flexible and robust.
61947107
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886You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
887handlers, installing new handlers was not atomic.
f39f21d8
JH
888
889=item *
890
1e13d81f
JH
891C<%INC> now localised in a Safe compartment so that use/require work.
892
893=item *
894
895The Shell module now has an OO interface.
896
897=item *
898
61947107 899The Test module has been significantly enhanced.
f39f21d8
JH
900
901=item *
902
61947107 903The C<vars> pragma now supports declaring fully qualified variables.
77c8cf41 904(Something that C<our()> does not and will not support.)
f39f21d8 905
888aee59
JH
906=item *
907
61947107
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908The utf8:: name space (as in the pragma) provides various
909Perl-callable functions to provide low level access to Perl's
910internal Unicode representation. At the moment only length()
911has been implemented.
888aee59 912
f39f21d8
JH
913=back
914
77c8cf41 915=head1 Utility Changes
f39f21d8
JH
916
917=over 4
918
919=item *
920
61947107 921Emacs perl mode (emacs/cperl-mode.el) has been updated to version
77c8cf41 9224.31.
f39f21d8
JH
923
924=item *
925
61947107 926F<emacs/e2ctags.pl> is now much faster.
f39f21d8
JH
927
928=item *
929
1e13d81f
JH
930C<h2ph> now supports C trigraphs.
931
932=item *
933
934C<h2xs> now produces a template README.
f39f21d8 935
77c8cf41
JH
936=item *
937
1e13d81f
JH
938C<h2xs> now uses C<Devel::PPort> for better portability between
939different versions of Perl.
f39f21d8
JH
940
941=item *
942
1e13d81f 943C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
61947107
JH
944newly created extensions that define constants. Since the new code is
945more correct (if you have two constants where the first one is a
946prefix of the second one, the first constant B<never> gets defined),
947less lossy (it uses integers for integer constant, as opposed to the
948old code that used floating point numbers even for integer constants),
949and slightly faster, you might want to consider regenerating your
950extension code (the new scheme makes regenerating easy).
951L<h2xs> now also supports C trigraphs.
f39f21d8
JH
952
953=item *
954
1e13d81f 955C<libnetcfg> has been added to configure the libnet.
f39f21d8
JH
956
957=item *
958
1e13d81f 959C<perlbug> is now much more robust. It also sends the bug report to
61947107 960perl.org, not perl.com.
f39f21d8
JH
961
962=item *
963
1e13d81f 964C<perlcc> has been rewritten and its user interface (that is,
61947107 965command line) is much more like that of the UNIX C compiler, cc.
f39f21d8
JH
966
967=item *
968
1e13d81f 969C<perlivp> is a new utility for doing Installation Verification
61947107 970Procedure after installing Perl.
f39f21d8
JH
971
972=item *
973
1e13d81f 974C<pod2html> now allows specifying a cache directory.
f39f21d8
JH
975
976=item *
977
1e13d81f
JH
978C<s2p> has been completely rewritten in Perl. (It is in fact a full
979implementation of sed in Perl: you can use the sed functionality by
980using the C<psed> utility.)
61947107
JH
981
982=item *
983
1e13d81f 984C<xsubpp> now understands POD documentation embedded in the *.xs files.
f39f21d8
JH
985
986=item *
987
1e13d81f 988C<xsubpp> now supports OUT keyword.
f39f21d8
JH
989
990=back
991
77c8cf41 992=head1 New Documentation
f39f21d8
JH
993
994=over 4
995
996=item *
997
77c8cf41
JH
998perl56delta details the changes between the 5.005 release and the
9995.6.0 release.
f39f21d8
JH
1000
1001=item *
1002
61947107
JH
1003perlclib documents the internal replacements for standard C library
1004functions. (Interesting only for extension writers and Perl core
1005hackers.)
1006
1007=item *
1008
77c8cf41 1009perldebtut is a Perl debugging tutorial.
f39f21d8 1010
77c8cf41 1011=item *
f39f21d8 1012
77c8cf41 1013perlebcdic contains considerations for running Perl on EBCDIC platforms.
057b7f2b
SG
1014Note that unfortunately EBCDIC platforms that used to be supported back
1015in Perl 5.005 are still unsupported by Perl 5.8.0; the plan, however, is
1016to bring them back to the fold.
f39f21d8 1017
77c8cf41
JH
1018=item *
1019
888aee59
JH
1020perlintro is a gentle introduction to Perl.
1021
1022=item *
1023
61947107
JH
1024perliol documents the internals of PerlIO with layers.
1025
1026=item *
1027
888aee59
JH
1028perlmodstyle is a style guide for writing modules.
1029
1030=item *
1031
77c8cf41 1032perlnewmod tells about writing and submitting a new module.
f39f21d8
JH
1033
1034=item *
1035
888aee59
JH
1036perlpod has been rewritten to be clearer and to record the best
1037practices gathered over the years.
1038
1039=item *
1040
057b7f2b 1041perlpodspec is a more formal specification of the pod format,
888aee59
JH
1042mainly of interest for writers of pod applications, not to
1043people writing in pod.
1044
1045=item *
1046
77c8cf41
JH
1047perlposix-bc explains using Perl on the POSIX-BC platform
1048(an EBCDIC mainframe platform).
f39f21d8
JH
1049
1050=item *
1051
77c8cf41 1052perlretut is a regular expression tutorial.
f39f21d8
JH
1053
1054=item *
1055
77c8cf41
JH
1056perlrequick is a regular expressions quick-start guide.
1057Yes, much quicker than perlretut.
f39f21d8 1058
77c8cf41 1059=item *
f39f21d8 1060
61947107
JH
1061perltodo has been updated.
1062
1063=item *
1064
888aee59 1065perltootc has been renamed as perltooc (to not to conflict
61947107 1066with perltoot in filesystems restricted to "8.3" names)
888aee59
JH
1067
1068=item *
1069
1070perluniintro is an introduction to using Unicode in Perl
1071(perlunicode is more of a reference)
1072
1073=item *
1074
77c8cf41
JH
1075perlutil explains the command line utilities packaged with the Perl
1076distribution.
1077
1078=back
f39f21d8 1079
61947107
JH
1080The following platform-specific documents are available before
1081the installation as README.I<platform>, and after the installation
1082as perlI<platform>:
f39f21d8 1083
61947107
JH
1084 perlaix perlamiga perlapollo perlbeos perlbs2000
1085 perlce perlcygwin perldgux perldos perlepoc perlhpux
1086 perlhurd perlmachten perlmacos perlmint perlmpeix
1087 perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
1088 perltru64 perluts perlvmesa perlvms perlvos perlwin32
77c8cf41
JH
1089
1090=over 4
1091
1092=item *
1093
61947107
JH
1094The documentation for the POSIX-BC platform is called "BS2000", to avoid
1095confusion with the Perl POSIX module.
77c8cf41
JH
1096
1097=item *
1098
61947107
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1099The documentation for the WinCE platform is called "CE", to avoid
1100confusion with the perlwin32 documentation on 8.3-restricted filesystems.
77c8cf41
JH
1101
1102=back
1103
1104=head1 Performance Enhancements
1105
1106=over 4
1107
1108=item *
1109
1110map() that changes the size of the list should now work faster.
1111
1112=item *
1113
e1f170bd
JH
1114sort() has been changed to use primarily mergesort internally as
1115opposed to the earlier quicksort. For very small lists this may
1116result in slightly slower sorting times, but in general the speedup
1117should be at least 20%. Additional bonuses are that the worst case
1118behaviour of sort() is now better (in computer science terms it now
1119runs in time O(N log N), as opposed to quicksort's Theta(N**2)
1120worst-case run time behaviour), and that sort() is now stable
1121(meaning that elements with identical keys will stay ordered as they
1122were before the sort). See the C<sort> pragma for information.
77c8cf41
JH
1123
1124=item *
1125
1126Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
1127(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
1128reasonably fast while producing a much better spread of values than
1129the old hashing algorithm (originally by Chris Torek, later tweaked by
1130Ilya Zakharevich). Hash values output from the algorithm on a hash of
1131all 3-char printable ASCII keys comes much closer to passing the
1132DIEHARD random number generation tests. According to perlbench, this
1133change has not affected the overall speed of Perl.
1134
1135=item *
1136
1137unshift() should now be noticeably faster.
1138
1139=back
1140
1141=head1 Installation and Configuration Improvements
1142
1143=head2 Generic Improvements
1144
1145=over 4
1146
1147=item *
1148
1149INSTALL now explains how you can configure Perl to use 64-bit
1150integers even on non-64-bit platforms.
1151
1152=item *
1153
1154Policy.sh policy change: if you are reusing a Policy.sh file
1155(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
1156Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
1157them will now be changed to the new prefix, /foo/bar. (Previously
1158only $prefix changed.) If you do not like this new behaviour,
1159specify prefix, siteprefix, and vendorprefix explicitly.
1160
1161=item *
1162
1163A new optional location for Perl libraries, otherlibdirs, is available.
1164It can be used for example for vendor add-ons without disturbing Perl's
1165own library directories.
1166
1167=item *
1168
1169In many platforms the vendor-supplied 'cc' is too stripped-down to
1170build Perl (basically, 'cc' doesn't do ANSI C). If this seems
1171to be the case and 'cc' does not seem to be the GNU C compiler
1172'gcc', an automatic attempt is made to find and use 'gcc' instead.
1173
1174=item *
1175
1176gcc needs to closely track the operating system release to avoid
1177build problems. If Configure finds that gcc was built for a different
1178operating system release than is running, it now gives a clearly visible
1179warning that there may be trouble ahead.
1180
1181=item *
1182
1183If binary compatibility with the 5.005 release is not wanted, Configure
1184no longer suggests including the 5.005 modules in @INC.
1185
1186=item *
1187
1188Configure C<-S> can now run non-interactively.
1189
1190=item *
1191
1192configure.gnu now works with options with whitespace in them.
f39f21d8 1193
77c8cf41 1194=item *
f39f21d8 1195
77c8cf41 1196installperl now outputs everything to STDERR.
f39f21d8 1197
77c8cf41
JH
1198=item *
1199
1200$Config{byteorder} is now computed dynamically (this is more robust
1201with "fat binaries" where an executable image contains binaries for
1202more than one binary platform.)
f39f21d8
JH
1203
1204=item *
1205
1206Because PerlIO is now the default on most platforms, "-perlio" doesn't
1207get appended to the $Config{archname} (also known as $^O) anymore.
1208Instead, if you explicitly choose not to use perlio (Configure command
1209line option -Uuseperlio), you will get "-stdio" appended.
1210
1211=item *
1212
1213Another change related to the architecture name is that "-64all"
1214(-Duse64bitall, or "maximally 64-bit") is appended only if your
1215pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
1216
1217=item *
1218
77c8cf41
JH
1219In AFS installations one can configure the root of the AFS to be
1220somewhere else than the default F</afs> by using the Configure
1221parameter C<-Dafsroot=/some/where/else>.
1222
1223=item *
1224
61947107
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1225APPLLIB_EXP, a less-know configuration-time definition, has been
1226documented. It can be used to prepend site-specific directories
1227to Perl's default search path (@INC), see INSTALL for information.
1228
1229=item *
1230
77c8cf41
JH
1231The version of Berkeley DB used when the Perl (and, presumably, the
1232DB_File extension) was built is now available as
1233C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
1234from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
1235DB_VERSION_PATCH_CFG> from C.
1236
1237=item *
1238
61947107
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1239Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
1240has been documented in INSTALL.
77c8cf41
JH
1241
1242=item *
1243
61947107
JH
1244If you have CPAN access (either network or a local copy such as a
1245CD-ROM) you can during specify extra modules to Configure to build and
1246install with Perl using the -Dextras=... option. See INSTALL for
1247more details.
f39f21d8 1248
61947107 1249=item *
f39f21d8 1250
61947107
JH
1251In addition to config.over a new override file, config.arch, is
1252available. That is supposed to be used by hints file writers for
1253architecture-wide changes (as opposed to config.over which is for
1254site-wide changes).
f39f21d8
JH
1255
1256=item *
1257
e1f170bd
JH
1258If your file system supports symbolic links you can build Perl outside
1259of the source directory by
1260
1261 mkdir /tmp/perl/build/directory
1262 cd /tmp/perl/build/directory
1263 sh /path/to/perl/source/Configure -Dmksymlinks ...
1264
1265This will create in /tmp/perl/build/directory a tree of symbolic links
1266pointing to files in /path/to/perl/source. The original files are left
1267unaffected. After Configure has finished you can just say
1268
1269 make all test
1270
1271and Perl will be built and tested, all in /tmp/perl/build/directory.
1272
1273=item *
1274
61947107
JH
1275For Perl developers several new make targets for profiling
1276and debugging have been added, see L<perlhack>.
1277
1278=over 8
f39f21d8
JH
1279
1280=item *
1281
61947107
JH
1282Use of the F<gprof> tool to profile Perl has been documented in
1283L<perlhack>. There is a make target called "perl.gprof" for
1284generating a gprofiled Perl executable.
f39f21d8
JH
1285
1286=item *
1287
61947107
JH
1288If you have GCC 3, there is a make target called "perl.gcov" for
1289creating a gcoved Perl executable for coverage analysis. See
1290L<perlhack>.
f39f21d8
JH
1291
1292=item *
1293
61947107
JH
1294If you are on IRIX or Tru64 platforms, new profiling/debugging options
1295have been added, see L<perlhack> for more information about pixie and
1296Third Degree.
1297
1298=back
f39f21d8
JH
1299
1300=item *
1301
61947107
JH
1302Guidelines of how to construct minimal Perl installations have
1303been added to INSTALL.
f39f21d8
JH
1304
1305=item *
1306
61947107
JH
1307The Thread extension is now not built at all under ithreads
1308(C<Configure -Duseithreads>) because it wouldn't work anyway (the
1309Thread extension requires being Configured with C<-Duse5005threads>).
f39f21d8 1310
61947107
JH
1311But note that the Thread.pm interface is now shared by both
1312thread models.
f39f21d8 1313
61947107 1314=back
f39f21d8 1315
61947107 1316=head2 New Or Improved Platforms
f39f21d8 1317
61947107
JH
1318For the list of platforms known to support Perl,
1319see L<perlport/"Supported Platforms">.
1320
1321=over 4
f39f21d8
JH
1322
1323=item *
1324
61947107 1325AIX dynamic loading should be now better supported.
f39f21d8 1326
f39f21d8
JH
1327=item *
1328
77c8cf41
JH
1329AIX should now work better with gcc, threads, and 64-bitness. Also the
1330long doubles support in AIX should be better now. See L<perlaix>.
f39f21d8
JH
1331
1332=item *
1333
61947107
JH
1334After a long pause, AmigaOS has been verified to be happy with Perl.
1335
1336=item *
1337
77c8cf41 1338AtheOS (http://www.atheos.cx/) is a new platform.
f39f21d8 1339
77c8cf41 1340=item *
f39f21d8 1341
77c8cf41 1342DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
f39f21d8
JH
1343
1344=item *
1345
77c8cf41 1346DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
f39f21d8
JH
1347
1348=item *
1349
61947107
JH
1350EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
1351have been regained. Many test suite tests still fail and the
1352co-existence of Unicode and EBCDIC isn't quite settled, but the
1353situation is much better than with Perl 5.6. See L<perlos390>,
1354L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
f39f21d8
JH
1355
1356=item *
1357
61947107
JH
1358Building perl with -Duseithreads or -Duse5005threads now works under
1359HP-UX 10.20 (previously it only worked under 10.30 or later). You will
1360need a thread library package installed. See README.hpux.
f39f21d8 1361
77c8cf41 1362=item *
f39f21d8 1363
61947107
JH
1364MacOS Classic (MacPerl has of course been available since
1365perl 5.004 but now the source code bases of standard Perl
1366and MacPerl have been synchronised)
f39f21d8 1367
77c8cf41 1368=item *
f39f21d8 1369
61947107
JH
1370MacOS X (or Darwin) should now be able to build Perl even on HFS+
1371filesystems. (The case-insensitivity confused the Perl build process.)
f39f21d8 1372
888aee59
JH
1373=item *
1374
61947107 1375NCR MP-RAS is now supported.
888aee59
JH
1376
1377=item *
1378
61947107 1379NetWare from Novell is now supported. See L<perlnetware>.
888aee59
JH
1380
1381=item *
1382
61947107 1383NonStop-UX is now supported.
888aee59
JH
1384
1385=item *
1386
61947107 1387Amdahl UTS UNIX mainframe platform is now supported.
888aee59
JH
1388
1389=item *
1390
61947107
JH
1391WinCE is now supported. See L<perlce>.
1392
1393=item *
1394
1395z/OS (formerly known as OS/390, formerly known as MVS OE) has now
1396support for dynamic loading. This is not selected by default,
1397however, you must specify -Dusedl in the arguments of Configure.
888aee59 1398
f39f21d8
JH
1399=back
1400
1401=head1 Selected Bug Fixes
1402
e1f170bd
JH
1403Numerous memory leaks and uninitialized memory accesses have been
1404hunted down. Most importantly anonymous subs used to leak quite
1405a bit.
ba370e9b 1406
f39f21d8
JH
1407=over 4
1408
1409=item *
1410
e1f170bd 1411The autouse pragma didn't work for Multi::Part::Function::Names.
f39f21d8
JH
1412
1413=item *
1414
e1f170bd
JH
1415chop(@list) in list context returned the characters chopped in
1416reverse order. This has been reversed to be in the right order.
f39f21d8
JH
1417
1418=item *
1419
e1f170bd
JH
1420Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
1421when building the Perl binary. The only exception to this is SunOS 4.x,
1422which needs them.
f39f21d8
JH
1423
1424=item *
1425
e1f170bd
JH
1426The behaviour of non-decimal but numeric string constants such as
1427"0x23" was platform-dependent: in some platforms that was seen as 35,
1428in some as 0, in some as a floating point number (don't ask). This
1429was caused by Perl using the operating system libraries in a situation
1430where the result of the string to number conversion is undefined: now
1431Perl consistently handles such strings as zero in numeric contexts.
f39f21d8
JH
1432
1433=item *
1434
e1f170bd 1435The order of DESTROYs has been made more predictable.
f39f21d8
JH
1436
1437=item *
1438
e1f170bd
JH
1439Several debugger fixes: exit code now reflects the script exit code,
1440condition C<"0"> now treated correctly, the C<d> command now checks
1441line number, the C<$.> no longer gets corrupted, all debugger output now
1442goes correctly to the socket if RemotePort is set.
f39f21d8
JH
1443
1444=item *
1445
e1f170bd 1446L<dprofpp> -R didn't work.
f39f21d8
JH
1447
1448=item *
1449
e1f170bd 1450C<*foo{FORMAT}> now works.
f39f21d8
JH
1451
1452=item *
1453
e1f170bd
JH
1454UNIVERSAL::isa no longer caches methods incorrectly. (This broke
1455the Tk extension with 5.6.0.)
f39f21d8
JH
1456
1457=item *
1458
e1f170bd
JH
1459Lexicals I: lexicals outside an eval "" weren't resolved
1460correctly inside a subroutine definition inside the eval "" if they
1461were not already referenced in the top level of the eval""ed code.
f39f21d8
JH
1462
1463=item *
1464
e1f170bd
JH
1465Lexicals II: lexicals leaked at file scope into subroutines that
1466were declared before the lexicals.
f39f21d8
JH
1467
1468=item *
1469
e1f170bd 1470Lexical warnings now propagating correctly between scopes.
f39f21d8
JH
1471
1472=item *
1473
e1f170bd 1474Line renumbering with eval and C<#line> now works.
f39f21d8
JH
1475
1476=item *
1477
e1f170bd 1478Fixed numerous memory leaks, especially in eval "".
f39f21d8
JH
1479
1480=item *
1481
e1f170bd
JH
1482mkdir() now ignores trailing slashes in the directory name,
1483as mandated by POSIX.
f39f21d8
JH
1484
1485=item *
1486
e1f170bd
JH
1487Some versions of glibc have a broken modfl(). This affects builds
1488with C<-Duselongdouble>. This version of Perl detects this brokenness
1489and has a workaround for it. The glibc release 2.2.2 is known to have
1490fixed the modfl() bug.
f39f21d8
JH
1491
1492=item *
1493
e1f170bd
JH
1494Modulus of unsigned numbers now works (4063328477 % 65535 used to
1495return 27406, instead of 27047).
f39f21d8
JH
1496
1497=item *
1498
e1f170bd
JH
1499Some "not a number" warnings introduced in 5.6.0 eliminated to be
1500more compatible with 5.005. Infinity is now recognised as a number.
f39f21d8 1501
77c8cf41 1502=item *
f39f21d8 1503
e1f170bd 1504Attributes (like :shared) didn't work with our().
f39f21d8
JH
1505
1506=item *
1507
e1f170bd 1508our() variables will not cause "will not stay shared" warnings.
f39f21d8
JH
1509
1510=item *
1511
e1f170bd 1512pack "Z" now correctly terminates the string with "\0".
f39f21d8
JH
1513
1514=item *
1515
e1f170bd
JH
1516Fix password routines which in some shadow password platforms
1517(e.g. HP-UX) caused getpwent() to return every other entry.
f39f21d8 1518
77c8cf41 1519=item *
f39f21d8 1520
e1f170bd
JH
1521The PERL5OPT environment variable (for passing command line arguments
1522to Perl) didn't work for more than a single group of options.
f39f21d8 1523
77c8cf41 1524=item *
f39f21d8 1525
e1f170bd 1526PERL5OPT with embedded spaces didn't work.
f39f21d8 1527
77c8cf41 1528=item *
f39f21d8 1529
e1f170bd 1530printf() no longer resets the numeric locale to "C".
f39f21d8 1531
77c8cf41 1532=item *
f39f21d8 1533
e1f170bd 1534C<q(a\\b)> now parses correctly as C<'a\\b'>.
f39f21d8 1535
77c8cf41 1536=item *
f39f21d8 1537
e1f170bd
JH
1538Printing quads (64-bit integers) with printf/sprintf now works
1539without the q L ll prefixes (assuming you are on a quad-capable platform).
f39f21d8 1540
77c8cf41 1541=item *
f39f21d8 1542
e1f170bd 1543Regular expressions on references and overloaded scalars now work.
f39f21d8 1544
ba370e9b
JH
1545=item *
1546
e1f170bd
JH
1547Right-hand side magic (GMAGIC) could in many cases such as string
1548concatenation be invoked too many times.
ba370e9b
JH
1549
1550=item *
1551
e1f170bd 1552scalar() now forces scalar context even when used in void context.
ba370e9b
JH
1553
1554=item *
1555
e1f170bd 1556SOCKS support is now much more robust.
ba370e9b
JH
1557
1558=item *
1559
e1f170bd
JH
1560sort() arguments are now compiled in the right wantarray context
1561(they were accidentally using the context of the sort() itself).
ba370e9b
JH
1562
1563=item *
1564
e1f170bd 1565Changed the POSIX character class C<[[:space:]]> to include the (very
c2e23569
JH
1566rarely used) vertical tab character. Added a new POSIX-ish character
1567class C<[[:blank:]]> which stands for horizontal whitespace
1568(currently, the space and the tab).
ba370e9b
JH
1569
1570=item *
1571
1572The tainting behaviour of sprintf() has been rationalized. It does
1573not taint the result of floating point formats anymore, making the
1574behaviour consistent with that of string interpolation.
1575
1576=item *
1577
c2e23569
JH
1578The regular expression captured submatches ($1, $2, ...) are now
1579more consistently unset if the match fails, instead of leaving false
1580data lying around in them.
1581
1582=item *
1583
1584C<Sys::Syslog> ignored the C<LOG_AUTH> constant.
ba370e9b
JH
1585
1586=item *
1587
e1f170bd 1588All but the first argument of the IO syswrite() method are now optional.
ba370e9b
JH
1589
1590=item *
1591
e1f170bd
JH
1592$AUTOLOAD, sort(), lock(), and spawning subprocesses
1593in multiple threads simultaneously are now thread-safe.
ba370e9b
JH
1594
1595=item *
1596
e1f170bd 1597Tie::ARRAY SPLICE method was broken.
ba370e9b
JH
1598
1599=item *
1600
e1f170bd 1601Allow read-only string on left hand side of non-modifying tr///.
ba370e9b
JH
1602
1603=item *
1604
e1f170bd 1605Several Unicode fixes.
ba370e9b
JH
1606
1607=over 8
1608
1609=item *
1610
e1f170bd
JH
1611BOMs (byte order marks) in the beginning of Perl files
1612(scripts, modules) should now be transparently skipped.
1613UTF-16 (UCS-2) encoded Perl files should now be read correctly.
ba370e9b
JH
1614
1615=item *
1616
e1f170bd 1617The character tables have been updated to Unicode 3.1.1.
ba370e9b
JH
1618
1619=item *
1620
e1f170bd
JH
1621Comparing with utf8 data does not magically upgrade non-utf8 data
1622into utf8.
ba370e9b
JH
1623
1624=item *
1625
e1f170bd 1626C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
f39f21d8 1627
77c8cf41 1628=item *
f39f21d8 1629
e1f170bd
JH
1630Concatenation with the C<.> operator or via variable interpolation,
1631C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
1632substitution with C<s///>, single-quoted UTF8, should now work.
f39f21d8 1633
77c8cf41 1634=item *
f39f21d8 1635
e1f170bd
JH
1636The C<tr///> operator now works. Note that the C<tr///CU>
1637functionality has been removed (but see pack('U0', ...)).
f39f21d8 1638
77c8cf41 1639=item *
f39f21d8 1640
e1f170bd 1641C<eval "v200"> now works.
f39f21d8 1642
77c8cf41 1643=item *
f39f21d8 1644
e1f170bd 1645Zero entries were missing from the Unicode classes like C<IsDigit>.
f39f21d8 1646
e1f170bd 1647=back
f39f21d8 1648
77c8cf41 1649=back
f39f21d8 1650
77c8cf41 1651=head2 Platform Specific Changes and Fixes
f39f21d8
JH
1652
1653=over 4
1654
1655=item *
1656
77c8cf41 1657BSDI 4.*
f39f21d8 1658
77c8cf41 1659Perl now works on post-4.0 BSD/OSes.
f39f21d8
JH
1660
1661=item *
1662
77c8cf41 1663All BSDs
f39f21d8 1664
057b7f2b 1665Setting C<$0> now works (as much as possible; see L<perlvar> for details).
f39f21d8
JH
1666
1667=item *
1668
77c8cf41 1669Cygwin
f39f21d8 1670
77c8cf41 1671Numerous updates; currently synchronised with Cygwin 1.1.4.
f39f21d8
JH
1672
1673=item *
1674
e1f170bd
JH
1675Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
1676
1677=item *
1678
77c8cf41 1679EPOC
f39f21d8 1680
77c8cf41 1681EPOC update after Perl 5.6.0. See README.epoc.
f39f21d8
JH
1682
1683=item *
1684
77c8cf41 1685FreeBSD 3.*
f39f21d8 1686
77c8cf41 1687Perl now works on post-3.0 FreeBSDs.
f39f21d8
JH
1688
1689=item *
1690
77c8cf41
JH
1691HP-UX
1692
1693README.hpux updated; C<Configure -Duse64bitall> now almost works.
f39f21d8
JH
1694
1695=item *
1696
77c8cf41 1697IRIX
f39f21d8 1698
77c8cf41
JH
1699Numerous compilation flag and hint enhancements; accidental mixing
1700of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
f39f21d8 1701
77c8cf41 1702=item *
f39f21d8 1703
77c8cf41 1704Linux
f39f21d8 1705
e1f170bd
JH
1706=over 8
1707
1708=item *
1709
77c8cf41 1710Long doubles should now work (see INSTALL).
f39f21d8
JH
1711
1712=item *
1713
e1f170bd
JH
1714Linux previously had problems related to sockaddrlen when using
1715accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
1716
1717=back
1718
1719=item *
1720
77c8cf41 1721MacOS Classic
f39f21d8 1722
77c8cf41
JH
1723Compilation of the standard Perl distribution in MacOS Classic should
1724now work if you have the Metrowerks development environment and
1725the missing Mac-specific toolkit bits. Contact the macperl mailing
1726list for details.
f39f21d8
JH
1727
1728=item *
1729
77c8cf41 1730MPE/iX
f39f21d8 1731
77c8cf41 1732MPE/iX update after Perl 5.6.0. See README.mpeix.
f39f21d8
JH
1733
1734=item *
1735
77c8cf41 1736NetBSD/sparc
f39f21d8 1737
77c8cf41 1738Perl now works on NetBSD/sparc.
f39f21d8
JH
1739
1740=item *
1741
77c8cf41 1742OS/2
f39f21d8 1743
77c8cf41 1744Now works with usethreads (see INSTALL).
f39f21d8
JH
1745
1746=item *
1747
77c8cf41 1748Solaris
f39f21d8 1749
77c8cf41 175064-bitness using the Sun Workshop compiler now works.
f39f21d8
JH
1751
1752=item *
1753
77c8cf41 1754Tru64 (aka Digital UNIX, aka DEC OSF/1)
f39f21d8 1755
77c8cf41
JH
1756The operating system version letter now recorded in $Config{osvers}.
1757Allow compiling with gcc (previously explicitly forbidden). Compiling
1758with gcc still not recommended because buggy code results, even with
1759gcc 2.95.2.
f39f21d8
JH
1760
1761=item *
1762
77c8cf41
JH
1763Unicos
1764
1765Fixed various alignment problems that lead into core dumps either
1766during build or later; no longer dies on math errors at runtime;
1767now using full quad integers (64 bits), previously was using
1768only 46 bit integers for speed.
f39f21d8
JH
1769
1770=item *
1771
77c8cf41
JH
1772VMS
1773
1774chdir() now works better despite a CRT bug; now works with MULTIPLICITY
1775(see INSTALL); now works with Perl's malloc.
f39f21d8
JH
1776
1777=item *
1778
77c8cf41 1779Windows
f39f21d8 1780
77c8cf41 1781=over 8
f39f21d8
JH
1782
1783=item *
1784
77c8cf41 1785accept() no longer leaks memory.
f39f21d8
JH
1786
1787=item *
1788
e1f170bd
JH
1789Borland C++ v5.5 is now a supported compiler that can build Perl.
1790However, the generated binaries continue to be incompatible with those
1791generated by the other supported compilers (GCC and Visual C++).
1792
1793=item *
1794
77c8cf41 1795Better chdir() return value for a non-existent directory.
f39f21d8 1796
77c8cf41 1797=item *
f39f21d8 1798
e1f170bd
JH
1799Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
1800
1801=item *
1802
77c8cf41 1803New %ENV entries now propagate to subprocesses.
f39f21d8
JH
1804
1805=item *
1806
77c8cf41
JH
1807$ENV{LIB} now used to search for libs under Visual C.
1808
1809=item *
1810
e1f170bd
JH
1811Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
1812Other bugs in chdir() and Cwd::cwd() have also been fixed.
1813
1814=item *
1815
77c8cf41 1816A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
f39f21d8
JH
1817
1818=item *
1819
e1f170bd
JH
1820HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
1821
1822=item *
1823
1824The makefiles now provide a single switch to bulk-enable all the features
1825enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
1826
1827=item *
1828
77c8cf41 1829Allow REG_EXPAND_SZ keys in the registry.
f39f21d8
JH
1830
1831=item *
1832
77c8cf41 1833Can now send() from all threads, not just the first one.
f39f21d8
JH
1834
1835=item *
1836
77c8cf41 1837Fake signal handling reenabled, bugs and all.
f39f21d8
JH
1838
1839=item *
1840
77c8cf41
JH
1841Less stack reserved per thread so that more threads can run
1842concurrently. (Still 16M per thread.)
f39f21d8
JH
1843
1844=item *
1845
c2e23569 1846C<File::Spec-&gt;tmpdir()> now prefers C:/temp over /tmp
77c8cf41 1847(works better when perl is running as service).
f39f21d8
JH
1848
1849=item *
1850
77c8cf41 1851Better UNC path handling under ithreads.
f39f21d8
JH
1852
1853=item *
1854
77c8cf41 1855wait() and waitpid() now work much better.
f39f21d8
JH
1856
1857=item *
1858
77c8cf41 1859winsock handle leak fixed.
f39f21d8
JH
1860
1861=back
1862
77c8cf41 1863=back
f39f21d8 1864
77c8cf41 1865=head1 New or Changed Diagnostics
f39f21d8 1866
ba370e9b
JH
1867=over 4
1868
1869=item *
1870
77c8cf41
JH
1871All regular expression compilation error messages are now hopefully
1872easier to understand both because the error message now comes before
1873the failed regex and because the point of failure is now clearly
ba370e9b
JH
1874marked by a C<E<lt>-- HERE> marker.
1875
1876=item *
f39f21d8 1877
77c8cf41
JH
1878The various "opened only for", "on closed", "never opened" warnings
1879drop the C<main::> prefix for filehandles in the C<main> package,
bea4d472 1880for example C<STDIN> instead of C<main::STDIN>.
f39f21d8 1881
ba370e9b
JH
1882=item *
1883
77c8cf41
JH
1884The "Unrecognized escape" warning has been extended to include C<\8>,
1885C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
f39f21d8 1886
ba370e9b 1887=item *
f39f21d8 1888
77c8cf41
JH
1889Two new debugging options have been added: if you have compiled your
1890Perl with debugging, you can use the -DT and -DR options to trace
1891tokenising and to add reference counts to displaying variables,
1892respectively.
f39f21d8
JH
1893
1894=item *
1895
77c8cf41
JH
1896If an attempt to use a (non-blessed) reference as an array index
1897is made, a warning is given.
f39f21d8
JH
1898
1899=item *
1900
77c8cf41
JH
1901C<push @a;> and C<unshift @a;> (with no values to push or unshift)
1902now give a warning. This may be a problem for generated and evaled
1903code.
f39f21d8 1904
ba370e9b
JH
1905=item *
1906
1907If you try to L<perlfunc/pack> a number less than 0 or larger than 255
1908using the C<"C"> format you will get an optional warning. Similarly
1909for the C<"c"> format and a number less than -128 or more than 127.
1910
1911=item *
1912
1913Certain regex modifiers such as C<(?o)> make sense only if applied to
1914the entire regex. You will an optional warning if you try to do otherwise.
1915
1916=item *
1917
c2e23569
JH
1918Using arrays or hashes as references (e.g. C<< %foo-&gt;{bar} >>
1919has been deprecated for a while. Now you will get an optional warning.
ba370e9b 1920
f39f21d8
JH
1921=back
1922
77c8cf41 1923=head1 Changed Internals
f39f21d8
JH
1924
1925=over 4
1926
1927=item *
1928
77c8cf41
JH
1929perlapi.pod (a companion to perlguts) now attempts to document the
1930internal API.
f39f21d8
JH
1931
1932=item *
1933
77c8cf41
JH
1934You can now build a really minimal perl called microperl.
1935Building microperl does not require even running Configure;
1936C<make -f Makefile.micro> should be enough. Beware: microperl makes
1937many assumptions, some of which may be too bold; the resulting
1938executable may crash or otherwise misbehave in wondrous ways.
1939For careful hackers only.
f39f21d8
JH
1940
1941=item *
1942
c2e23569
JH
1943Added rsignal(), whichsig(), do_join(), op_clear, op_null,
1944ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
1945interfaces to the publicised API. For the full list of the available
1946APIs see L<perlapi>.
f39f21d8
JH
1947
1948=item *
1949
77c8cf41 1950Made possible to propagate customised exceptions via croak()ing.
f39f21d8 1951
77c8cf41 1952=item *
f39f21d8 1953
77c8cf41 1954Now xsubs can have attributes just like subs.
f39f21d8
JH
1955
1956=item *
1957
77c8cf41
JH
1958dTHR and djSP have been obsoleted; the former removed (because it's
1959a no-op) and the latter replaced with dSP.
f39f21d8
JH
1960
1961=item *
1962
61947107
JH
1963PERL_OBJECT has been completely removed.
1964
1965=item *
1966
ba370e9b
JH
1967The MAGIC constants (e.g. C<'P'>) have been macrofied
1968(e.g. C<PERL_MAGIC_TIED>) for better source code readability
1969and maintainability.
1970
1971=item *
1972
1973The regex compiler now maintains a structure that identifies nodes in
1974the compiled bytecode with the corresponding syntactic features of the
1975original regex expression. The information is attached to the new
1976C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
1977complete information.
1978
1979=item *
1980
1981The C code has been made much more C<gcc -Wall> clean. Some warning
1982messages still remain in some platforms, so if you are compiling with
1983gcc you may see some warnings about dubious practices. The warnings
1984are being worked on.
1985
1986=item *
1987
1988F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
1989
1990=item *
1991
61947107
JH
1992Documentation on how to use the Perl source repository has been added
1993to F<Porting/repository.pod>.
f39f21d8 1994
888aee59
JH
1995=item *
1996
c2e23569 1997There are now several profiling make targets.
888aee59 1998
77c8cf41 1999=back
f39f21d8 2000
77c8cf41 2001=head1 Security Vulnerability Closed
f39f21d8 2002
77c8cf41 2003(This change was already made in 5.7.0 but bears repeating here.)
f39f21d8 2004
77c8cf41
JH
2005A potential security vulnerability in the optional suidperl component
2006of Perl was identified in August 2000. suidperl is neither built nor
2007installed by default. As of November 2001 the only known vulnerable
2008platform is Linux, most likely all Linux distributions. CERT and
2009various vendors and distributors have been alerted about the vulnerability.
2010See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
2011for more information.
f39f21d8 2012
77c8cf41
JH
2013The problem was caused by Perl trying to report a suspected security
2014exploit attempt using an external program, /bin/mail. On Linux
2015platforms the /bin/mail program had an undocumented feature which
2016when combined with suidperl gave access to a root shell, resulting in
2017a serious compromise instead of reporting the exploit attempt. If you
2018don't have /bin/mail, or if you have 'safe setuid scripts', or if
2019suidperl is not installed, you are safe.
f39f21d8 2020
77c8cf41
JH
2021The exploit attempt reporting feature has been completely removed from
2022Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
2023from all the Perl 5.7 releases), so that particular vulnerability
2024isn't there anymore. However, further security vulnerabilities are,
ba370e9b
JH
2025unfortunately, always possible. The suidperl functionality is most
2026probably going to be removed in Perl 5.10. In any case, suidperl
2027should only be used by security experts who know exactly what they are
2028doing and why they are using suidperl instead of some other solution
2029such as sudo (see http://www.courtesan.com/sudo/).
77c8cf41
JH
2030
2031=head1 New Tests
2032
2033Several new tests have been added, especially for the F<lib> subsection.
2034
2035The tests are now reported in a different order than in earlier Perls.
2036(This happens because the test scripts from under t/lib have been moved
2037to be closer to the library/extension they are testing.)
2038
f39f21d8
JH
2039=head1 Known Problems
2040
2041Note that unlike other sections in this document (which describe
2042changes since 5.7.0) this section is cumulative containing known
2043problems for all the 5.7 releases.
2044
2045=head2 AIX
2046
2047=over 4
2048
2049=item *
2050
2051In AIX 4.2 Perl extensions that use C++ functions that use statics
2052may have problems in that the statics are not getting initialized.
2053In newer AIX releases this has been solved by linking Perl with
2054the libC_r library, but unfortunately in AIX 4.2 the said library
2055has an obscure bug where the various functions related to time
2056(such as time() and gettimeofday()) return broken values, and
2057therefore in AIX 4.2 Perl is not linked against the libC_r.
2058
2059=item *
2060
2061vac 5.0.0.0 May Produce Buggy Code For Perl
2062
2063The AIX C compiler vac version 5.0.0.0 may produce buggy code,
2064resulting in few random tests failing, but when the failing tests
2065are run by hand, they succeed. We suggest upgrading to at least
2066vac version 5.0.1.0, that has been known to compile Perl correctly.
2067"lslpp -L|grep vac.C" will tell you the vac version.
2068
2069=back
2070
2071=head2 Amiga Perl Invoking Mystery
2072
2073One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
057b7f2b 2074works, but for example C<bin:perl -v> doesn't. The exact reason isn't
f39f21d8
JH
2075known but the current suspect is the F<ixemul> library.
2076
2077=head2 lib/ftmp-security tests warn 'system possibly insecure'
2078
2079Don't panic. Read INSTALL 'make test' section instead.
2080
2081=head2 Cygwin intermittent failures of lib/Memoize/t/expire_file 11 and 12
2082
2083The subtests 11 and 12 sometimes fail and sometimes work.
2084
2085=head2 HP-UX lib/io_multihomed Fails When LP64-Configured
2086
2087The lib/io_multihomed test may hang in HP-UX if Perl has been
2088configured to be 64-bit. Because other 64-bit platforms do not hang in
2089this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
2090test attempts to create and connect to "multihomed" sockets (sockets
2091which have multiple IP addresses).
2092
2093=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
2094
2095If perl is configured with -Duse64bitall, the successful result of the
2096subtest 10 of lib/posix may arrive before the successful result of the
2097subtest 9, which confuses the test harness so much that it thinks the
2098subtest 9 failed.
2099
2100=head2 Linux With Sfio Fails op/misc Test 48
2101
2102No known fix.
2103
2104=head2 OS/390
2105
2106OS/390 has rather many test failures but the situation is actually
2107better than it was in 5.6.0, it's just that so many new modules and
2108tests have been added.
2109
2110 Failed Test Stat Wstat Total Fail Failed List of Failed
2111 -----------------------------------------------------------------------------
2112 ../ext/B/Deparse.t 14 1 7.14% 14
2113 ../ext/B/Showlex.t 1 1 100.00% 1
2114 ../ext/Encode/Encode/Tcl.t 610 13 2.13% 592 594 596 598
2115 600 602 604-610
2116 ../ext/IO/lib/IO/t/io_unix.t 113 28928 5 3 60.00% 3-5
2117 ../ext/POSIX/POSIX.t 29 1 3.45% 14
2118 ../ext/Storable/t/lock.t 255 65280 5 3 60.00% 3-5
2119 ../lib/locale.t 129 33024 117 19 16.24% 99-117
2120 ../lib/warnings.t 434 1 0.23% 75
2121 ../lib/ExtUtils.t 27 1 3.70% 25
2122 ../lib/Math/BigInt/t/bigintpm.t 1190 1 0.08% 1145
2123 ../lib/Unicode/UCD.t 81 48 59.26% 1-16 49-64 66-81
2124 ../lib/User/pwent.t 9 1 11.11% 4
2125 op/pat.t 660 6 0.91% 242-243 424-425
2126 626-627
2127 op/split.t 0 9 ?? ?? % ??
2128 op/taint.t 174 3 1.72% 156 162 168
2129 op/tr.t 70 3 4.29% 50 58-59
2130 Failed 16/422 test scripts, 96.21% okay. 105/23251 subtests failed, 99.55% okay.
2131
2132=head2 op/sprintf tests 129 and 130
2133
2134The op/sprintf tests 129 and 130 are known to fail on some platforms.
2135Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
2136The failing platforms do not comply with the ANSI C Standard, line
213719ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
2138something other than "1" and "-1" when formatting 0.6 and -0.6 using
2139the printf format "%.0f", most often they produce "0" and "-0".)
2140
2141=head2 Failure of Thread tests
2142
2143B<Note that support for 5.005-style threading remains experimental.>
2144
2145The following tests are known to fail due to fundamental problems in
2146the 5.005 threading implementation. These are not new failures--Perl
21475.005_0x has the same bugs, but didn't have these tests.
2148
2149 lib/autouse.t 4
2150 t/lib/thr5005.t 19-20
2151
2152=head2 UNICOS
2153
2154=over 4
2155
2156=item *
2157
2158ext/POSIX/sigaction subtests 6 and 13 may fail.
2159
2160=item *
2161
2162lib/ExtUtils may spuriously claim that subtest 28 failed,
2163which is interesting since the test only has 27 tests.
2164
2165=item *
2166
2167Numerous numerical test failures
2168
2169 op/numconvert 209,210,217,218
2170 op/override 7
2171 ext/Time/HiRes/HiRes 9
2172 lib/Math/BigInt/t/bigintpm 1145
2173 lib/Math/Trig 25
2174
2175These tests fail because of yet unresolved floating point inaccuracies.
2176
2177=back
2178
2179=head2 UTS
2180
2181There are a few known test failures, see L<perluts>.
2182
2183=head2 VMS
2184
057b7f2b
SG
2185Rather a lot of tests are failing in VMS, but actually more tests
2186succeed in VMS than they used to; it's just that there are many,
f39f21d8
JH
2187many more tests than there used to be.
2188
2189Here are the known failures from some compiler/platform combinations.
2190
2191DEC C V5.3-006 on OpenVMS VAX V6.2
ba370e9b 2192
f39f21d8
JH
2193 [-.ext.list.util.t]tainted..............FAILED on test 3
2194 [-.ext.posix]sigaction..................FAILED on test 7
2195 [-.ext.time.hires]hires.................FAILED on test 14
2196 [-.lib.file.find]taint..................FAILED on test 17
2197 [-.lib.math.bigint.t]bigintpm...........FAILED on test 1183
2198 [-.lib.test.simple.t]exit...............FAILED on test 1
2199 [.lib]vmsish............................FAILED on test 13
2200 [.op]sprintf............................FAILED on test 12
2201 Failed 8/399 tests, 91.23% okay.
2202
2203DEC C V6.0-001 on OpenVMS Alpha V7.2-1 and
2204Compaq C V6.2-008 on OpenVMS Alpha V7.1
2205
2206 [-.ext.list.util.t]tainted..............FAILED on test 3
2207 [-.lib.file.find]taint..................FAILED on test 17
2208 [-.lib.test.simple.t]exit...............FAILED on test 1
2209 [.lib]vmsish............................FAILED on test 13
2210 Failed 4/399 tests, 92.48% okay.
2211
2212Compaq C V6.4-005 on OpenVMS Alpha 7.2.1
2213
2214 [-.ext.b]showlex........................FAILED on test 1
2215 [-.ext.list.util.t]tainted..............FAILED on test 3
2216 [-.lib.file.find]taint..................FAILED on test 17
2217 [-.lib.test.simple.t]exit...............FAILED on test 1
2218 [.lib]vmsish............................FAILED on test 13
2219 [.op]misc...............................FAILED on test 49
2220 Failed 6/401 tests, 92.77% okay.
2221
2222=head2 Win32
2223
2224In multi-CPU boxes there are some problems with the I/O buffering:
2225some output may appear twice.
2226
2227=head2 Localising a Tied Variable Leaks Memory
2228
2229 use Tie::Hash;
2230 tie my %tie_hash => 'Tie::StdHash';
2231
2232 ...
2233
2234 local($tie_hash{Foo}) = 1; # leaks
2235
2236Code like the above is known to leak memory every time the local()
2237is executed.
2238
2239=head2 Self-tying of Arrays and Hashes Is Forbidden
2240
2241Self-tying of arrays and hashes is broken in rather deep and
2242hard-to-fix ways. As a stop-gap measure to avoid people from getting
2243frustrated at the mysterious results (core dumps, most often) it is
2244for now forbidden (you will get a fatal error even from an attempt).
2245
2246=head2 Variable Attributes are not Currently Usable for Tieing
2247
2248This limitation will hopefully be fixed in future. (Subroutine
2249attributes work fine for tieing, see L<Attribute::Handlers>).
2250
2251=head2 Building Extensions Can Fail Because Of Largefiles
2252
2253Some extensions like mod_perl are known to have issues with
2254`largefiles', a change brought by Perl 5.6.0 in which file offsets
2255default to 64 bits wide, where supported. Modules may fail to compile
2256at all or compile and work incorrectly. Currently there is no good
2257solution for the problem, but Configure now provides appropriate
2258non-largefile ccflags, ldflags, libswanted, and libs in the %Config
2259hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
2260having problems can try configuring themselves without the
2261largefileness. This is admittedly not a clean solution, and the
2262solution may not even work at all. One potential failure is whether
2263one can (or, if one can, whether it's a good idea) link together at
2264all binaries with different ideas about file offsets, all this is
2265platform-dependent.
2266
2267=head2 The Compiler Suite Is Still Experimental
2268
2269The compiler suite is slowly getting better but is nowhere near
2270working order yet.
2271
2272=head2 The Long Double Support is Still Experimental
2273
2274The ability to configure Perl's numbers to use "long doubles",
2275floating point numbers of hopefully better accuracy, is still
2276experimental. The implementations of long doubles are not yet
2277widespread and the existing implementations are not quite mature
2278or standardised, therefore trying to support them is a rare
2279and moving target. The gain of more precision may also be offset
2280by slowdown in computations (more bits to move around, and the
2281operations are more likely to be executed by less optimised
2282libraries).
33a87e58 2283
cc0fca54
GS
2284=head1 Reporting Bugs
2285
d4ad863d
JH
2286If you find what you think is a bug, you might check the articles
2287recently posted to the comp.lang.perl.misc newsgroup and the perl
2288bug database at http://bugs.perl.org. There may also be
2289information at http://www.perl.com/perl/, the Perl Home Page.
cc0fca54
GS
2290
2291If you believe you have an unreported bug, please run the B<perlbug>
2292program included with your release. Be sure to trim your bug down
2293to a tiny but sufficient test case. Your bug report, along with the
d4ad863d 2294output of C<perl -V>, will be sent off to perlbug@perl.org to be
cc0fca54
GS
2295analysed by the Perl porting team.
2296
2297=head1 SEE ALSO
2298
2299The F<Changes> file for exhaustive details on what changed.
2300
2301The F<INSTALL> file for how to build Perl.
2302
2303The F<README> file for general stuff.
2304
2305The F<Artistic> and F<Copying> files for copyright information.
2306
2307=head1 HISTORY
2308
d468ca04 2309Written by Jarkko Hietaniemi <F<jhi@iki.fi>>.
cc0fca54
GS
2310
2311=cut