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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
8and the 5.8.0 release.
f39f21d8 9
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10Many of the bug fixes in 5.8.0 were already seen in the 5.6.1
11maintenance release since the two releases were kept closely
12coordinated.
13
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14If you are upgrading from Perl 5.005_03, you might also want
15to read L<perl56delta>.
16
44da0e71 17=head1 Highlights In 5.8.0
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18
19=over 4
20
21=item *
22
23Better Unicode support
24
25=item *
26
27New Thread Implementation
28
29=item *
30
31Many New Modules
32
33=item *
34
35Better Numeric Accuracy
36
37=item *
38
39Safe Signals
40
41=item *
42
43More Extensive Regression Testing
44
45=back
46
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47=head1 Incompatible Changes
48
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49=head2 64-bit platforms and malloc
50
057b7f2b 51If your pointers are 64 bits wide, the Perl malloc is no longer being
c2e23569 52used because it does not work well with 8-byte pointers. Also,
61947107 53usually the system mallocs on such platforms are much better optimized
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54for such large memory models than the Perl malloc. Some memory-hungry
55Perl applications like the PDL don't work well with Perl's malloc.
56Finally, other applications than Perl (like modperl) tend to prefer
57the system malloc. Such platforms include Alpha and 64-bit HPPA,
58MIPS, PPC, and Sparc.
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59
60=head2 AIX Dynaloading
61
62The AIX dynaloading now uses in AIX releases 4.3 and newer the native
63dlopen interface of AIX instead of the old emulated interface. This
64change will probably break backward compatibility with compiled
65modules. The change was made to make Perl more compliant with other
66applications like modperl which are using the AIX native interface.
67
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68=head2 Attributes for C<my> variables now handled at run-time.
69
70The C<my EXPR : ATTRS> syntax now applies variable attributes at
71run-time. (Subroutine and C<our> variables still get attributes applied
72at compile-time.) See L<attributes> for additional details. In particular,
73however, this allows variable attributes to be useful for C<tie> interfaces,
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74which was a deficiency of earlier releases. Note that the new semantics
75doesn't work with the Attribute::Handlers module (as of version 0.76).
95f0a2f1 76
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77=head2 Socket Extension Dynamic in VMS
78
79The Socket extension is now dynamically loaded instead of being
80statically built in. This may or may not be a problem with ancient
81TCP/IP stacks of VMS: we do not know since we weren't able to test
82Perl in such configurations.
83
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84=head2 IEEE-format Floating Point Default on OpenVMS Alpha
85
86Perl now uses IEEE format (T_FLOAT) as the default internal floating
87point format on OpenVMS Alpha, potentially breaking binary compatibility
88with external libraries or existing data. G_FLOAT is still available as
89a configuration option. The default on VAX (D_FLOAT) has not changed.
90
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91=head2 New Unicode Properties
92
93Unicode I<scripts> are now supported. Scripts are similar to (and superior
94to) Unicode I<blocks>. The difference between scripts and blocks is that
95scripts are the glyphs used by a language or a group of languages, while
96the blocks are more artificial groupings of (mostly) 256 characters based
97on the Unicode numbering.
98
99In general, scripts are more inclusive, but not universally so. For
100example, while the script C<Latin> includes all the Latin characters and
101their various diacritic-adorned versions, it does not include the various
102punctuation or digits (since they are not solely C<Latin>).
103
104A number of other properties are now supported, including C<\p{L&}>,
105C<\p{Any}> C<\p{Assigned}>, C<\p{Unassigned}>, C<\p{Blank}> and
106C<\p{SpacePerl}> (along with their C<\P{...}> versions, of course).
107See L<perlunicode> for details, and more additions.
108
109The C<In> or C<Is> prefix to names used with the C<\p{...}> and C<\P{...}>
110are now almost always optional. The only exception is that a C<In> prefix
111is required to signify a Unicode block when a block name conflicts with a
112script name. For example, C<\p{Tibetan}> refers to the script, while
113C<\p{InTibetan}> refers to the block. When there is no name conflict, you
114can omit the C<In> from the block name (e.g. C<\p{BraillePatterns}>), but
115to be safe, it's probably best to always use the C<In>).
77c8cf41 116
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117=head2 Perl Parser Stress Tested
118
119The Perl parser has been stress tested using both random input and
120Markov chain input and the few found crashes and lockups have been
121fixed.
122
c2e23569 123=head2 REF(...) Instead Of SCALAR(...)
77c8cf41 124
057b7f2b 125A reference to a reference now stringifies as "REF(0x81485ec)" instead
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126of "SCALAR(0x81485ec)" in order to be more consistent with the return
127value of ref().
77c8cf41 128
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129=head2 pack/unpack D/F recycled
130
66023b77 131The undocumented pack/unpack template letters D/F have been recycled
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132for better use: now they stand for long double (if supported by the
133platform) and NV (Perl internal floating point type). (They used
134to be aliases for f/d, but you never knew that.)
135
c2e23569 136=head2 Deprecations
77c8cf41 137
61947107 138=over 4
77c8cf41 139
61947107 140=item *
f39f21d8 141
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142The semantics of bless(REF, REF) were unclear and until someone proves
143it to make some sense, it is forbidden.
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144
145=item *
146
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147The obsolete chat2 library that should never have been allowed
148to escape the laboratory has been decommissioned.
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149
150=item *
151
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152The builtin dump() function has probably outlived most of its
153usefulness. The core-dumping functionality will remain in future
154available as an explicit call to C<CORE::dump()>, but in future
155releases the behaviour of an unqualified C<dump()> call may change.
156
157=item *
158
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159The very dusty examples in the eg/ directory have been removed.
160Suggestions for new shiny examples welcome but the main issue is that
161the examples need to be documented, tested and (most importantly)
162maintained.
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163
164=item *
165
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166The (bogus) escape sequences \8 and \9 now give an optional warning
167("Unrecognized escape passed through"). There is no need to \-escape
168any C<\w> character.
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169
170=item *
171
c2e23569 172The list of filenames from glob() (or <...>) is now by default sorted
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173alphabetically to be csh-compliant (which is what happened before
174in most UNIX platforms). (bsd_glob() does still sort platform
c2e23569 175natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
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176
177=item *
178
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179Spurious syntax errors generated in certain situations, when glob()
180caused File::Glob to be loaded for the first time, have been fixed.
181
182=item *
183
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184Although "you shouldn't do that", it was possible to write code that
185depends on Perl's hashed key order (Data::Dumper does this). The new
186algorithm "One-at-a-Time" produces a different hashed key order.
187More details are in L</"Performance Enhancements">.
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188
189=item *
190
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191lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
192In future releases this may become a fatal error.
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193
194=item *
195
057b7f2b 196The C<package;> syntax (C<package> without an argument) has been
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197deprecated. Its semantics were never that clear and its
198implementation even less so. If you have used that feature to
199disallow all but fully qualified variables, C<use strict;> instead.
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200
201=item *
202
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203The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
204recognised but now cause fatal errors. The previous behaviour of
205ignoring them by default and warning if requested was unacceptable
206since it, in a way, falsely promised that the features could be used.
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207
208=item *
209
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210The current user-visible implementation of pseudo-hashes (the weird
211use of the first array element) is deprecated starting from Perl 5.8.0
212and will be removed in Perl 5.10.0, and the feature will be
213implemented differently. Not only is the current interface rather
214ugly, but the current implementation slows down normal array and hash
215use quite noticeably. The C<fields> pragma interface will remain
216available.
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217
218=item *
219
aecce728 220The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
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221
222=item *
223
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224After years of trying the suidperl is considered to be too complex to
225ever be considered truly secure. The suidperl functionality is likely
226to be removed in a future release.
227
228=item *
229
230The long deprecated uppercase aliases for the string comparison
231operators (EQ, NE, LT, LE, GE, GT) have now been removed.
232
233=item *
234
235The tr///C and tr///U features have been removed and will not return;
236the interface was a mistake. Sorry about that. For similar
237functionality, see pack('U0', ...) and pack('C0', ...).
f39f21d8 238
420cdfc1
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239=item *
240
241Earlier Perls treated "sub foo (@bar)" as equivalent to "sub foo (@)".
242The prototypes are now checked at compile-time for invalid characters.
243An optional warning is generated ("Illegal character in prototype...")
244but this may be upgraded to a fatal error in a future release.
245
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246=back
247
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248=head1 Core Enhancements
249
77c8cf41 250=head2 PerlIO is Now The Default
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251
252=over 4
253
254=item *
255
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256IO is now by default done via PerlIO rather than system's "stdio".
257PerlIO allows "layers" to be "pushed" onto a file handle to alter the
258handle's behaviour. Layers can be specified at open time via 3-arg
259form of open:
f39f21d8 260
77c8cf41 261 open($fh,'>:crlf :utf8', $path) || ...
f39f21d8 262
77c8cf41 263or on already opened handles via extended C<binmode>:
f39f21d8 264
77c8cf41 265 binmode($fh,':encoding(iso-8859-7)');
f39f21d8 266
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267The built-in layers are: unix (low level read/write), stdio (as in
268previous Perls), perlio (re-implementation of stdio buffering in a
269portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
270but available on any platform). A mmap layer may be available if
271platform supports it (mostly UNIXes).
f39f21d8 272
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273Layers to be applied by default may be specified via the 'open' pragma.
274
275See L</"Installation and Configuration Improvements"> for the effects
276of PerlIO on your architecture name.
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277
278=item *
279
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280File handles can be marked as accepting Perl's internal encoding of Unicode
281(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
f39f21d8 282
77c8cf41 283 open($fh,">:utf8","Uni.txt");
f39f21d8 284
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285Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
286for you since it's not UTF-8 what you will be getting but instead
287UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
288http://www.unicode.org/unicode/reports/tr16/ for more information.
289In future releases this naming may change.
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290
291=item *
292
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293File handles can translate character encodings from/to Perl's internal
294Unicode form on read/write via the ":encoding()" layer.
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295
296=item *
297
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298File handles can be opened to "in memory" files held in Perl scalars via:
299
300 open($fh,'>', \$variable) || ...
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301
302=item *
303
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304Anonymous temporary files are available without need to
305'use FileHandle' or other module via
f39f21d8 306
77c8cf41 307 open($fh,"+>", undef) || ...
f39f21d8 308
77c8cf41 309That is a literal undef, not an undefined value.
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310
311=item *
312
77c8cf41 313The list form of C<open> is now implemented for pipes (at least on UNIX):
f39f21d8 314
77c8cf41 315 open($fh,"-|", 'cat', '/etc/motd')
f39f21d8 316
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317creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
318the child process.
f39f21d8 319
e1f170bd 320=back
f39f21d8 321
3e33716f 322=head2 Safe Signals
f39f21d8 323
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324Perl used to be fragile in that signals arriving at inopportune moments
325could corrupt Perl's internal state. Now Perl postpones handling of
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326signals until it's safe (between opcodes).
327
56e5bb57 328This change may have surprising side effects because signals no longer
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329interrupt Perl instantly. Perl will now first finish whatever it was
330doing, like finishing an internal operation (like sort()) or an
331external operation (like an I/O operation), and only then look at any
332arrived signals (and before starting the next operation). No more corrupt
333internal state since the current operation is always finished first,
334but the signal may take more time to get heard.
f39f21d8 335
e1f170bd 336=head2 Unicode Overhaul
f39f21d8 337
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338Unicode in general should be now much more usable than in Perl 5.6.0
339(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
340regular expressions should work now, Unicode in tr/// should work now,
341Unicode in I/O should work now.
f39f21d8 342
e1f170bd 343=over 4
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344
345=item *
346
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347The Unicode Character Database coming with Perl has been upgraded
348to Unicode 3.1.1. For more information, see http://www.unicode.org/.
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349
350=item *
351
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352For developers interested in enhancing Perl's Unicode capabilities:
353almost all the UCD files are included with the Perl distribution in
58175c9b 354the F<lib/unicore subdirectory>. The most notable omission, for space
77c8cf41 355considerations, is the Unihan database.
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356
357=item *
358
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359The properties \p{Blank} and \p{SpacePerl} have been added. "Blank" is like
360C isblank(), that is, it contains only "horizontal whitespace" (the space
361character is, the newline isn't), and the "SpacePerl" is the Unicode
362equivalent of C<\s> (\p{Space} isn't, since that includes the vertical
363tabulator character, whereas C<\s> doesn't.)
364
365See "New Unicode Properties" earlier in this document for additional
366information on changes with Unicode properties.
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367
368=back
369
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370=head2 Understanding of Numbers
371
372In general a lot of fixing has happened in the area of Perl's
373understanding of numbers, both integer and floating point. Since in
374many systems the standard number parsing functions like C<strtoul()>
375and C<atof()> seem to have bugs, Perl tries to work around their
376deficiencies. This results hopefully in more accurate numbers.
f39f21d8 377
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378Perl now tries internally to use integer values in numeric conversions
379and basic arithmetics (+ - * /) if the arguments are integers, and
380tries also to keep the results stored internally as integers.
057b7f2b 381This change leads to often slightly faster and always less lossy
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382arithmetics. (Previously Perl always preferred floating point numbers
383in its math.)
384
58175c9b 385=head2 Miscellaneous Changes
e1f170bd 386
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387=over 4
388
389=item *
390
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391AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
392to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
393
394=item *
395
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396C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
397in multiple arguments.)
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398
399=item *
400
58175c9b 401The builtin dump() now gives an optional warning
66023b77 402C<dump() better written as CORE::dump()>,
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403meaning that by default C<dump(...)> is resolved as the builtin
404dump() which dumps core and aborts, not as (possibly) user-defined
405C<sub dump>. To call the latter, qualify the call as C<&dump(...)>.
406(The whole dump() feature is to considered deprecated, and possibly
407removed/changed in future releases.)
408
409=item *
410
66023b77 411chomp() and chop() have been demoted back to I<not> being overridable
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412because they cannot really be overridden-- the problem is that their
413prototype cannot be expressed and therefore one really cannot write
414replacements to override these builtins.
415
416=item *
417
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418END blocks are now run even if you exit/die in a BEGIN block.
419Internally, the execution of END blocks is now controlled by
420PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
421behaviour for Perl embedders. This will default in 5.10. See
422L<perlembed>.
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423
424=item *
425
e1f170bd 426Formats now support zero-padded decimal fields.
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427
428=item *
429
77c8cf41 430Lvalue subroutines can now return C<undef> in list context.
44da0e71 431However, the lvalue subroutine feature still remains experimental.
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432
433=item *
434
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435A lost warning "Can't declare ... dereference in my" has been
436restored (Perl had it earlier but it became lost in later releases.)
437
438=item *
439
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440A new special regular expression variable has been introduced:
441C<$^N>, which contains the most-recently closed group (submatch).
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442
443=item *
444
61947107 445C<no Module;> now works even if there is no "sub unimport" in the Module.
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446
447=item *
448
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449The numerical comparison operators return C<undef> if either operand
450is a NaN. Previously the behaviour was unspecified.
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451
452=item *
453
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454The following builtin functions are now overridable: each(), keys(),
455pop(), push(), shift(), splice(), unshift().
456
457=item *
458
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459C<pack() / unpack()> now can group template letters with C<()> and then
460apply repetition/count modifiers on the groups.
461
462=item *
463
464C<pack() / unpack()> can now process the Perl internal numeric types:
465IVs, UVs, NVs-- and also long doubles, if supported by the platform.
79f69e33 466The template letters are C<j>, C<J>, C<F>, and C<D>.
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467
468=item *
469
61947107 470C<pack('U0a*', ...)> can now be used to force a string to UTF8.
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471
472=item *
473
61947107 474my __PACKAGE__ $obj now works.
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475
476=item *
477
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478The printf() and sprintf() now support parameter reordering using the
479C<%\d+\$> and C<*\d+\$> syntaxes. For example
480
481 print "%2\$s %1\$s\n", "foo", "bar";
482
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483will print "bar foo\n". This feature helps in writing
484internationalised software, and in general when the order
485of the parameters can vary.
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486
487=item *
488
e1f170bd 489prototype(\&) is now available.
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490
491=item *
492
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493prototype(\[$@%&]) is now available to implicitly create references
494(useful for example if you want to emulate the tie() interface).
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495
496=item *
497
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498A new command-line option, C<-t> is available. It is the
499little brother of C<-T>: instead of dieing on taint violations,
500lexical warnings are given. B<This is only meant as a temporary
501debugging aid while securing the code of old legacy applications.
502This is not a substitute for -T.>
503
504=item *
505
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506In other taint news, the C<exec LIST> and C<system LIST> have now been
507considered too risky (think C<exec @ARGV>: it can start any program
508with any arguments), and now the said forms cause a warning.
509You should carefully launder the arguments to guarantee their
510validity. In future releases of Perl the forms will become fatal
511errors so consider starting laundering now.
512
513=item *
514
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515If tr/// is just counting characters, it doesn't attempt to
516modify its target.
517
518=item *
519
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520untie() will now call an UNTIE() hook if it exists. See L<perltie>
521for details.
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522
523=item *
524
525L<utime> now supports C<utime undef, undef, @files> to change the
526file timestamps to the current time.
527
528=item *
529
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530The rules for allowing underscores (underbars) in numeric constants
531have been relaxed and simplified: now you can have an underscore
532simply B<between digits>.
f39f21d8 533
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534=item *
535
536Rather than relying on C's argv[0] (which may not contain a full pathname)
537where possible $^X is now set by asking the operating system.
538(eg by reading F</proc/self/exe> on Linux, F</proc/curproc/file> on FreeBSD)
539
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540=back
541
77c8cf41 542=head1 Modules and Pragmata
f39f21d8 543
1e13d81f 544=head2 New Modules and Pragmata
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545
546=over 4
547
548=item *
549
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550C<Attribute::Handlers> allows a class to define attribute handlers.
551
552 package MyPack;
553 use Attribute::Handlers;
554 sub Wolf :ATTR(SCALAR) { print "howl!\n" }
555
556 # later, in some package using or inheriting from MyPack...
557
558 my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
559
560Both variables and routines can have attribute handlers. Handlers can
561be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
562exact compilation phase (BEGIN, CHECK, INIT, or END).
563
564=item *
565
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566B<B::Concise> is a new compiler backend for walking the Perl syntax
567tree, printing concise info about ops, from Stephen McCamant. The
568output is highly customisable. See L<B::Concise>.
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569
570=item *
571
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572C<Class::ISA> for reporting the search path for a class's ISA tree,
573by Sean Burke, has been added. See L<Class::ISA>.
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574
575=item *
576
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577C<Cwd> has now a split personality: if possible, an XS extension is
578used, (this will hopefully be faster, more secure, and more robust)
579but if not possible, the familiar Perl implementation is used.
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580
581=item *
582
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583C<Devel::PPPort>, originally from Kenneth Albanowski and now
584maintained by Paul Marquess, has been added. It is primarily used
66023b77 585by C<h2xs> to enhance portability of XS modules between different
e1f170bd 586versions of Perl.
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587
588=item *
589
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590C<Digest>, frontend module for calculating digests (checksums), from
591Gisle Aas, has been added. See L<Digest>.
f39f21d8
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592
593=item *
594
61947107
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595C<Digest::MD5> for calculating MD5 digests (checksums) as defined in
596RFC 1321, from Gisle Aas, has been added. See L<Digest::MD5>.
f39f21d8
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597
598 use Digest::MD5 'md5_hex';
599
600 $digest = md5_hex("Thirsty Camel");
601
602 print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
603
61947107 604NOTE: the C<MD5> backward compatibility module is deliberately not
e1f170bd 605included since its further use is discouraged.
f39f21d8 606
f39f21d8
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607=item *
608
61947107 609C<Encode>, by Nick Ing-Simmons, provides a mechanism to translate
f39f21d8
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610between different character encodings. Support for Unicode,
611ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
612compiled in to the module. Several other encodings (like Japanese,
613Chinese, and MacIntosh encodings) are included and will be loaded at
61947107 614runtime. See L<Encode>.
f39f21d8
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615
616Any encoding supported by Encode module is also available to the
617":encoding()" layer if PerlIO is used.
618
61947107
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619=item *
620
621C<I18N::Langinfo> can be use to query locale information.
622See L<I18N::Langinfo>.
f39f21d8
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623
624=item *
625
61947107 626C<I18N::LangTags> has functions for dealing with RFC3066-style
bea4d472 627language tags, by Sean Burke. See L<I18N::LangTags>.
61947107
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628
629=item *
630
631C<ExtUtils::Constant> is a new tool for extension writers for
632generating XS code to import C header constants, by Nicholas Clark.
633See L<ExtUtils::Constant>.
634
635=item *
636
637C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
638from Damian Conway. See L<Filter::Simple>.
f39f21d8
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639
640 # in MyFilter.pm:
641
642 package MyFilter;
643
644 use Filter::Simple sub {
645 while (my ($from, $to) = splice @_, 0, 2) {
646 s/$from/$to/g;
647 }
648 };
649
650 1;
651
652 # in user's code:
653
654 use MyFilter qr/red/ => 'green';
655
656 print "red\n"; # this code is filtered, will print "green\n"
657 print "bored\n"; # this code is filtered, will print "bogreen\n"
658
659 no MyFilter;
660
661 print "red\n"; # this code is not filtered, will print "red\n"
662
61947107
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663=item *
664
665C<File::Temp> allows one to create temporary files and directories in
666an easy, portable, and secure way, by Tim Jenness. See L<File::Temp>.
667
668=item *
669
670C<Filter::Util::Call> provides you with the framework to write
671I<Source Filters> in Perl, from Paul Marquess. For most uses the
672frontend Filter::Simple is to be preferred. See L<Filter::Util::Call>.
673
674=item *
675
79f69e33
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676C<if> is a new pragma for conditional inclusion of modules, from
677Ilya Zakharevich.
678
679=item *
680
61947107
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681L<libnet> is a collection of perl5 modules related to network
682programming, from Graham Barr. See L<Net::FTP>, L<Net::NNTP>,
683L<Net::Ping>, L<Net::POP3>, L<Net::SMTP>, and L<Net::Time>.
684
685Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
f39f21d8
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686
687=item *
688
61947107 689C<List::Util> is a selection of general-utility list subroutines, like
bea4d472 690sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
f39f21d8
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691
692=item *
693
61947107
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694C<Locale::Constants>, C<Locale::Country>, C<Locale::Currency>, and
695C<Locale::Language>, from Neil Bowers, have been added. They provide the
696codes for various locale standards, such as "fr" for France, "usd" for
697US Dollar, and "jp" for Japanese.
f39f21d8
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698
699 use Locale::Country;
700
701 $country = code2country('jp'); # $country gets 'Japan'
702 $code = country2code('Norway'); # $code gets 'no'
703
704See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
61947107
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705and L<Locale::Language>.
706
707=item *
708
709C<Locale::Maketext> is localization framework from Sean Burke. See
710L<Locale::Maketext>, and L<Locale::Maketext::TPJ13>. The latter is an
711article about software localization, originally published in The Perl
712Journal #13, republished here with kind permission.
713
714=item *
715
716C<Memoize> can make your functions faster by trading space for time,
717from Mark-Jason Dominus. See L<Memoize>.
f39f21d8
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718
719=item *
720
61947107
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721C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
722as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
723Extensions)>.
f39f21d8
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724
725 use MIME::Base64;
726
727 $encoded = encode_base64('Aladdin:open sesame');
728 $decoded = decode_base64($encoded);
729
730 print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
731
61947107 732See L<MIME::Base64>.
f39f21d8
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733
734=item *
735
61947107
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736C<MIME::QuotedPrint> allows you to encode data in quoted-printable
737encoding, as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
738Extensions)>, from Gisle Aas.
f39f21d8
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739
740 use MIME::QuotedPrint;
741
742 $encoded = encode_qp("Smiley in Unicode: \x{263a}");
743 $decoded = decode_qp($encoded);
744
745 print $encoded, "\n"; # "Smiley in Unicode: =263A"
746
747MIME::QuotedPrint has been enhanced to provide the basic methods
748necessary to use it with PerlIO::Via as in :
749
750 use MIME::QuotedPrint;
057b7f2b 751 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8 752
61947107 753See L<MIME::QuotedPrint>.
f39f21d8
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754
755=item *
756
61947107
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757C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
758See L<NEXT>.
f39f21d8
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759
760=item *
761
1e13d81f
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762C<open> is a new pragma for setting the default I/O disciplines
763for open().
764
765=item *
766
61947107
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767C<PerlIO::Scalar> provides the implementation of IO to "in memory"
768Perl scalars as discussed above, from Nick Ing-Simmons. It also
769serves as an example of a loadable PerlIO layer. Other future
770possibilities include PerlIO::Array and PerlIO::Code.
771See L<PerlIO::Scalar>.
772
773=item *
774
775C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
776functionality provided by a class (typically implemented in perl
777code), from Nick Ing-Simmons.
f39f21d8
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778
779 use MIME::QuotedPrint;
057b7f2b 780 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8
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781
782This will automatically convert everything output to C<$fh>
61947107 783to Quoted-Printable. See L<PerlIO::Via>.
f39f21d8
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784
785=item *
786
1e13d81f 787C<Pod::ParseLink>, by Russ Allbery, has been added,
95f0a2f1 788to parse LZ<><> links in pods as described in the new
1e13d81f
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789perlpodspec.
790
791=item *
792
61947107 793C<Pod::Text::Overstrike>, by Joe Smith, has been added.
f39f21d8 794It converts POD data to formatted overstrike text.
61947107 795See L<Pod::Text::Overstrike>.
f39f21d8
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796
797=item *
798
61947107
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799C<Scalar::Util> is a selection of general-utility scalar subroutines,
800like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
801
802=item *
803
1e13d81f
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804C<sort> is a new pragma for controlling the behaviour of sort().
805
806=item *
807
61947107
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808C<Storable> gives persistence to Perl data structures by allowing the
809storage and retrieval of Perl data to and from files in a fast and
810compact binary format, from Raphael Manfredi. See L<Storable>.
811
812=item *
813
814C<Switch>, from Damian Conway, has been added. Just by saying
f39f21d8
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815
816 use Switch;
817
818you have C<switch> and C<case> available in Perl.
819
820 use Switch;
821
822 switch ($val) {
823
824 case 1 { print "number 1" }
825 case "a" { print "string a" }
826 case [1..10,42] { print "number in list" }
827 case (@array) { print "number in list" }
828 case /\w+/ { print "pattern" }
829 case qr/\w+/ { print "pattern" }
830 case (%hash) { print "entry in hash" }
831 case (\%hash) { print "entry in hash" }
832 case (\&sub) { print "arg to subroutine" }
833 else { print "previous case not true" }
834 }
835
61947107
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836See L<Switch>.
837
838=item *
839
840C<Test::More> is yet another framework for writing test scripts,
841more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
842
843=item *
844
aecce728 845C<Test::Simple> has basic utilities for writing tests, by Michael
61947107 846Schwern. See L<Test::Simple>.
77c8cf41
JH
847
848=item *
849
61947107
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850C<Text::Balanced> has been added, for extracting delimited text
851sequences from strings, from Damian Conway.
77c8cf41
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852
853 use Text::Balanced 'extract_delimited';
854
855 ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
856
857$a will be "'never say never'", $b will be ', he never said'.
858
859In addition to extract_delimited() there are also extract_bracketed(),
860extract_quotelike(), extract_codeblock(), extract_variable(),
861extract_tagged(), extract_multiple(), gen_delimited_pat(), and
862gen_extract_tagged(). With these you can implement rather advanced
61947107 863parsing algorithms. See L<Text::Balanced>.
77c8cf41
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864
865=item *
866
c2e23569 867C<threads> is an interface to interpreter threads, by Arthur Bergman.
61947107 868Interpreter threads (ithreads) is the new thread model introduced in
c2e23569
JH
869Perl 5.6 but only available as an internal interface for extension
870writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
77c8cf41
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871
872=item *
873
61947107
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874C<threads::shared> allows data sharing for interpreter threads, from
875Arthur Bergman. In the ithreads model any data sharing between
876threads must be explicit, as opposed to the old 5.005 thread model
877where data sharing was implicit. See L<threads::shared>.
77c8cf41
JH
878
879=item *
880
1f089b22
JH
881C<Tie::File>, by Mark-Jason Dominus, associates a Perl array with the
882lines of a file.
b3b08c80
JH
883
884=item *
885
79f69e33
JH
886C<Tie::Memoize>, by Ilya Zakharevich, provides on-demand loaded hashes.
887
888=item *
889
61947107 890C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
ba370e9b
JH
891references (unlike the standard Tie::RefHash) The module is contained
892within Tie::RefHash, see L<Tie::RefHash>.
77c8cf41
JH
893
894=item *
895
61947107
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896C<Time::HiRes> provides high resolution timing (ualarm, usleep,
897and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
77c8cf41
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898
899=item *
900
61947107
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901C<Unicode::UCD> offers a querying interface to the Unicode Character
902Database. See L<Unicode::UCD>.
77c8cf41
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903
904=item *
905
61947107
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906C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
907for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
77c8cf41
JH
908
909=item *
910
61947107
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911C<Unicode::Normalize> implements the various Unicode normalization
912forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
77c8cf41
JH
913
914=item *
915
61947107
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916C<XS::Typemap>, by Tim Jenness, is a test extension that exercises XS
917typemaps. Nothing gets installed but for extension writers the code
918is worth studying.
77c8cf41
JH
919
920=back
921
922=head2 Updated And Improved Modules and Pragmata
923
924=over 4
925
926=item *
927
61947107
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928The following independently supported modules have been updated to the
929newest versions from CPAN: CGI, CPAN, DB_File, File::Spec, File::Temp,
930Getopt::Long, Math::BigFloat, Math::BigInt, the podlators bundle
931(Pod::Man, Pod::Text), Pod::LaTeX, Pod::Parser, Storable,
932Term::ANSIColor, Test, Text-Tabs+Wrap.
77c8cf41
JH
933
934=item *
935
61947107 936The attributes::reftype() now works on tied arguments.
77c8cf41
JH
937
938=item *
939
057b7f2b 940AutoLoader can now be disabled with C<no AutoLoader;>.
77c8cf41
JH
941
942=item *
943
1e13d81f
JH
944B::Deparse has been significantly enhanced. It now can deparse almost
945all of the standard test suite (so that the tests still succeed).
946There is a make target "test.deparse" for trying this out.
77c8cf41
JH
947
948=item *
949
1e13d81f 950Class::Struct can now define the classes in compile time.
77c8cf41
JH
951
952=item *
953
1e13d81f
JH
954Class::Struct now assigns the array/hash element if the accessor
955is called with an array/hash element as the B<sole> argument.
77c8cf41
JH
956
957=item *
958
1e13d81f 959Data::Dumper has now an option to sort hashes.
77c8cf41
JH
960
961=item *
962
1e13d81f
JH
963Data::Dumper has now an option to dump code references
964using B::Deparse.
77c8cf41
JH
965
966=item *
967
44da0e71
JH
968DB_File now supports newer Berkeley DB versions, among
969other improvements.
970
971=item *
972
1e13d81f
JH
973The English module can now be used without the infamous performance
974hit by saying
77c8cf41 975
66023b77 976 use English '-no_match_vars';
77c8cf41 977
1e13d81f
JH
978(Assuming, of course, that one doesn't need the troublesome variables
979C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
980C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
77c8cf41
JH
981
982=item *
983
1e13d81f
JH
984Fcntl, Socket, and Sys::Syslog have been rewritten to use the
985new-style constant dispatch section (see L<ExtUtils::Constant>).
986This means that they will be more robust and hopefully faster.
77c8cf41
JH
987
988=item *
989
44da0e71
JH
990File::Find now chdir()s correctly when chasing symbolic links.
991
992=item *
993
1e13d81f
JH
994File::Find now has pre- and post-processing callbacks. It also
995correctly changes directories when chasing symbolic links. Callbacks
996(naughtily) exiting with "next;" instead of "return;" now work.
61947107
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997
998=item *
999
1e13d81f
JH
1000File::Find is now (again) reentrant. It also has been made
1001more portable.
77c8cf41 1002
61947107
JH
1003=item *
1004
1e13d81f
JH
1005File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
1006prototype mismatch with CORE::glob().
61947107
JH
1007
1008=item *
1009
1010File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
1011the returned list of filenames.
77c8cf41
JH
1012
1013=item *
1014
1015Devel::Peek now has an interface for the Perl memory statistics
1016(this works only if you are using perl's malloc, and if you have
1017compiled with debugging).
1018
1019=item *
1020
1e13d81f
JH
1021IPC::Open3 now allows the use of numeric file descriptors.
1022
1023=item *
1024
77c8cf41
JH
1025IO::Socket has now atmark() method, which returns true if the socket
1026is positioned at the out-of-band mark. The method is also exportable
1027as a sockatmark() function.
1028
1029=item *
1030
1031IO::Socket::INET has support for ReusePort option (if your platform
1032supports it). The Reuse option now has an alias, ReuseAddr. For clarity
1033you may want to prefer ReuseAddr.
1034
1035=item *
1036
61947107
JH
1037IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
1038that the operating system will make one up.)
77c8cf41
JH
1039
1040=item *
1041
1e13d81f
JH
1042use lib now works identically to @INC. Removing directories
1043with 'no lib' now works.
1044
1045=item *
1046
58175c9b
JH
1047ExtUtils::MakeMaker now uses File::Spec internally, which hopefully
1048leads into better portability.
1049
1050=item *
1051
1e13d81f
JH
1052Math::BigFloat and Math::BigInt have undergone a full rewrite.
1053They are now magnitudes faster, and they support various
61947107 1054bignum libraries such as GMP and PARI as their backends.
f39f21d8
JH
1055
1056=item *
1057
44da0e71
JH
1058Math::Complex handles inf, NaN etc., better.
1059
1060=item *
1061
58175c9b
JH
1062Net::Ping has been muchly enhanced. Multihoming is now supported.
1063There is now "external" protocol which uses Net::Ping::External module
1064which runs external ping(1) and parses the output. A version of
1065Net::Ping::External is available in CPAN.
f39f21d8 1066
77c8cf41 1067=item *
f39f21d8 1068
da6838c8 1069POSIX::sigaction() is now much more flexible and robust.
61947107
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1070You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
1071handlers, installing new handlers was not atomic.
f39f21d8
JH
1072
1073=item *
1074
da6838c8 1075In Safe the C<%INC> now localised in a Safe compartment so that
76663d67
JH
1076use/require work.
1077
1078=item *
1079
44da0e71
JH
1080In SDBM_File on dosish platforms, some keys went missing because of
1081lack of support for files with "holes". A workaround for the problem
1082has been added.
1083
1084=item *
1085
da6838c8 1086In Search::Dict one can now have a pre-processing hook for the
76663d67 1087lines being searched.
1e13d81f
JH
1088
1089=item *
1090
1091The Shell module now has an OO interface.
1092
1093=item *
1094
61947107 1095The Test module has been significantly enhanced.
f39f21d8
JH
1096
1097=item *
1098
da6838c8 1099The vars pragma now supports declaring fully qualified variables.
77c8cf41 1100(Something that C<our()> does not and will not support.)
f39f21d8 1101
888aee59
JH
1102=item *
1103
58175c9b 1104The C<utf8::> name space (as in the pragma) provides various
61947107
JH
1105Perl-callable functions to provide low level access to Perl's
1106internal Unicode representation. At the moment only length()
1107has been implemented.
888aee59 1108
f39f21d8
JH
1109=back
1110
77c8cf41 1111=head1 Utility Changes
f39f21d8
JH
1112
1113=over 4
1114
1115=item *
1116
61947107 1117Emacs perl mode (emacs/cperl-mode.el) has been updated to version
77c8cf41 11184.31.
f39f21d8
JH
1119
1120=item *
1121
61947107 1122F<emacs/e2ctags.pl> is now much faster.
f39f21d8
JH
1123
1124=item *
1125
1e13d81f
JH
1126C<h2ph> now supports C trigraphs.
1127
1128=item *
1129
1130C<h2xs> now produces a template README.
f39f21d8 1131
77c8cf41
JH
1132=item *
1133
1e13d81f
JH
1134C<h2xs> now uses C<Devel::PPort> for better portability between
1135different versions of Perl.
f39f21d8
JH
1136
1137=item *
1138
1e13d81f 1139C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
61947107
JH
1140newly created extensions that define constants. Since the new code is
1141more correct (if you have two constants where the first one is a
1142prefix of the second one, the first constant B<never> gets defined),
1143less lossy (it uses integers for integer constant, as opposed to the
1144old code that used floating point numbers even for integer constants),
1145and slightly faster, you might want to consider regenerating your
1146extension code (the new scheme makes regenerating easy).
1147L<h2xs> now also supports C trigraphs.
f39f21d8
JH
1148
1149=item *
1150
1e13d81f 1151C<libnetcfg> has been added to configure the libnet.
f39f21d8
JH
1152
1153=item *
1154
1e13d81f 1155C<perlbug> is now much more robust. It also sends the bug report to
61947107 1156perl.org, not perl.com.
f39f21d8
JH
1157
1158=item *
1159
1e13d81f 1160C<perlcc> has been rewritten and its user interface (that is,
61947107 1161command line) is much more like that of the UNIX C compiler, cc.
44da0e71 1162(The perlbc tools has been removed. Use C<perlcc -B> instead.)
f39f21d8
JH
1163
1164=item *
1165
aecce728
JH
1166C<perlivp> is a new Installation Verification Procedure utility
1167for running any time after installing Perl.
f39f21d8
JH
1168
1169=item *
1170
1e13d81f 1171C<pod2html> now allows specifying a cache directory.
f39f21d8
JH
1172
1173=item *
1174
1e13d81f
JH
1175C<s2p> has been completely rewritten in Perl. (It is in fact a full
1176implementation of sed in Perl: you can use the sed functionality by
1177using the C<psed> utility.)
61947107
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1178
1179=item *
1180
1e13d81f 1181C<xsubpp> now understands POD documentation embedded in the *.xs files.
f39f21d8
JH
1182
1183=item *
1184
1e13d81f 1185C<xsubpp> now supports OUT keyword.
f39f21d8
JH
1186
1187=back
1188
77c8cf41 1189=head1 New Documentation
f39f21d8
JH
1190
1191=over 4
1192
1193=item *
1194
77c8cf41
JH
1195perl56delta details the changes between the 5.005 release and the
11965.6.0 release.
f39f21d8
JH
1197
1198=item *
1199
61947107
JH
1200perlclib documents the internal replacements for standard C library
1201functions. (Interesting only for extension writers and Perl core
1202hackers.)
1203
1204=item *
1205
77c8cf41 1206perldebtut is a Perl debugging tutorial.
f39f21d8 1207
77c8cf41 1208=item *
f39f21d8 1209
77c8cf41 1210perlebcdic contains considerations for running Perl on EBCDIC platforms.
f39f21d8 1211
77c8cf41
JH
1212=item *
1213
888aee59
JH
1214perlintro is a gentle introduction to Perl.
1215
1216=item *
1217
61947107
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1218perliol documents the internals of PerlIO with layers.
1219
1220=item *
1221
888aee59
JH
1222perlmodstyle is a style guide for writing modules.
1223
1224=item *
1225
77c8cf41 1226perlnewmod tells about writing and submitting a new module.
f39f21d8
JH
1227
1228=item *
1229
34babc16
JH
1230perlpacktut is a pack() tutorial.
1231
1232=item *
1233
888aee59
JH
1234perlpod has been rewritten to be clearer and to record the best
1235practices gathered over the years.
1236
1237=item *
1238
057b7f2b 1239perlpodspec is a more formal specification of the pod format,
888aee59
JH
1240mainly of interest for writers of pod applications, not to
1241people writing in pod.
1242
1243=item *
1244
77c8cf41 1245perlretut is a regular expression tutorial.
f39f21d8
JH
1246
1247=item *
1248
77c8cf41
JH
1249perlrequick is a regular expressions quick-start guide.
1250Yes, much quicker than perlretut.
f39f21d8 1251
77c8cf41 1252=item *
f39f21d8 1253
61947107
JH
1254perltodo has been updated.
1255
1256=item *
1257
888aee59 1258perltootc has been renamed as perltooc (to not to conflict
61947107 1259with perltoot in filesystems restricted to "8.3" names)
888aee59
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1260
1261=item *
1262
58175c9b
JH
1263perluniintro is an introduction to using Unicode in Perl.
1264(perlunicode is more of a detailed reference and background
1265information)
888aee59
JH
1266
1267=item *
1268
77c8cf41
JH
1269perlutil explains the command line utilities packaged with the Perl
1270distribution.
1271
1272=back
f39f21d8 1273
61947107
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1274The following platform-specific documents are available before
1275the installation as README.I<platform>, and after the installation
1276as perlI<platform>:
f39f21d8 1277
61947107
JH
1278 perlaix perlamiga perlapollo perlbeos perlbs2000
1279 perlce perlcygwin perldgux perldos perlepoc perlhpux
1280 perlhurd perlmachten perlmacos perlmint perlmpeix
1281 perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
1282 perltru64 perluts perlvmesa perlvms perlvos perlwin32
77c8cf41
JH
1283
1284=over 4
1285
1286=item *
1287
61947107
JH
1288The documentation for the POSIX-BC platform is called "BS2000", to avoid
1289confusion with the Perl POSIX module.
77c8cf41
JH
1290
1291=item *
1292
61947107
JH
1293The documentation for the WinCE platform is called "CE", to avoid
1294confusion with the perlwin32 documentation on 8.3-restricted filesystems.
77c8cf41
JH
1295
1296=back
1297
1298=head1 Performance Enhancements
1299
1300=over 4
1301
1302=item *
1303
44da0e71
JH
1304map() could get pathologically slow when the result list it generates
1305is larger than the source list. The performance has been improved for
1306common scenarios.
77c8cf41
JH
1307
1308=item *
1309
e1f170bd
JH
1310sort() has been changed to use primarily mergesort internally as
1311opposed to the earlier quicksort. For very small lists this may
1312result in slightly slower sorting times, but in general the speedup
1313should be at least 20%. Additional bonuses are that the worst case
1314behaviour of sort() is now better (in computer science terms it now
1315runs in time O(N log N), as opposed to quicksort's Theta(N**2)
1316worst-case run time behaviour), and that sort() is now stable
1317(meaning that elements with identical keys will stay ordered as they
1318were before the sort). See the C<sort> pragma for information.
77c8cf41 1319
05e25c75
JH
1320The story in more detail: suppose you want to serve yourself a little
1321slice of Pi.
1322
1323 @digits = ( 3,1,4,1,5,9 );
1324
1325A numerical sort of the digits will yield (1,1,3,4,5,9), as expected.
1326Which C<1> comes first is hard to know, since one C<1> looks pretty
1327much like any other. You can regard this as totally trivial,
1328or somewhat profound. However, if you just want to sort the even
1329digits ahead of the odd ones, then what will
1330
1331 sort { ($a % 2) <=> ($b % 2) } @digits;
1332
1333yield? The only even digit, C<4>, will come first. But how about
1334the odd numbers, which all compare equal? With the quicksort algorithm
1335used to implement Perl 5.6 and earlier, the order of ties is left up
1336to the sort. So, as you add more and more digits of Pi, the order
1337in which the sorted even and odd digits appear will change.
1338and, for sufficiently large slices of Pi, the quicksort algorithm
1339in Perl 5.8 won't return the same results even if reinvoked with the
1340same input. The justification for this rests with quicksort's
1341worst case behavior. If you run
1342
1343 sort { $a <=> $b } ( 1 .. $N , 1 .. $N );
1344
1345(something you might approximate if you wanted to merge two sorted
1346arrays using sort), doubling $N doesn't just double the quicksort time,
1347it I<quadruples> it. Quicksort has a worst case run time that can
1348grow like N**2, so-called I<quadratic> behaviour, and it can happen
1349on patterns that may well arise in normal use. You won't notice this
1350for small arrays, but you I<will> notice it with larger arrays,
1351and you may not live long enough for the sort to complete on arrays
1352of a million elements. So the 5.8 quicksort scrambles large arrays
1353before sorting them, as a statistical defence against quadratic behaviour.
1354But that means if you sort the same large array twice, ties may be
1355broken in different ways.
1356
1357Because of the unpredictability of tie-breaking order, and the quadratic
1358worst-case behaviour, quicksort was I<almost> replaced completely with
1359a stable mergesort. I<Stable> means that ties are broken to preserve
1360the original order of appearance in the input array. So
1361
1362 sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
1363
1364will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers
1365appear in the output in the same order they appeared in the input.
1366Mergesort has worst case O(NlogN) behaviour, the best value
1367attainable. And, ironically, this mergesort does particularly
1368well where quicksort goes quadratic: mergesort sorts (1..$N, 1..$N)
1369in O(N) time. But quicksort was rescued at the last moment because
1370it is faster than mergesort on certain inputs and platforms.
1371For example, if you really I<don't> care about the order of even
1372and odd digits, quicksort will run in O(N) time; it's very good
1373at sorting many repetitions of a small number of distinct elements.
1374The quicksort divide and conquer strategy works well on platforms
1375with relatively small, very fast, caches. Eventually, the problem gets
1376whittled down to one that fits in the cache, from which point it
1377benefits from the increased memory speed.
1378
1379Quicksort was rescued by implementing a sort pragma to control aspects
1380of the sort. The B<stable> subpragma forces stable behaviour,
1381regardless of algorithm. The B<_quicksort> and B<_mergesort>
1382subpragmas are heavy-handed ways to select the underlying implementation.
1383The leading C<_> is a reminder that these subpragmas may not survive
1384beyond 5.8. More appropriate mechanisms for selecting the implementation
1385exist, but they wouldn't have arrived in time to save quicksort.
1386
77c8cf41
JH
1387=item *
1388
1389Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
1390(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
1391reasonably fast while producing a much better spread of values than
1392the old hashing algorithm (originally by Chris Torek, later tweaked by
1393Ilya Zakharevich). Hash values output from the algorithm on a hash of
1394all 3-char printable ASCII keys comes much closer to passing the
1395DIEHARD random number generation tests. According to perlbench, this
1396change has not affected the overall speed of Perl.
1397
1398=item *
1399
1400unshift() should now be noticeably faster.
1401
1402=back
1403
1404=head1 Installation and Configuration Improvements
1405
1406=head2 Generic Improvements
1407
1408=over 4
1409
1410=item *
1411
1412INSTALL now explains how you can configure Perl to use 64-bit
1413integers even on non-64-bit platforms.
1414
1415=item *
1416
1417Policy.sh policy change: if you are reusing a Policy.sh file
1418(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
1419Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
1420them will now be changed to the new prefix, /foo/bar. (Previously
1421only $prefix changed.) If you do not like this new behaviour,
1422specify prefix, siteprefix, and vendorprefix explicitly.
1423
1424=item *
1425
1426A new optional location for Perl libraries, otherlibdirs, is available.
1427It can be used for example for vendor add-ons without disturbing Perl's
1428own library directories.
1429
1430=item *
1431
1432In many platforms the vendor-supplied 'cc' is too stripped-down to
1433build Perl (basically, 'cc' doesn't do ANSI C). If this seems
1434to be the case and 'cc' does not seem to be the GNU C compiler
1435'gcc', an automatic attempt is made to find and use 'gcc' instead.
1436
1437=item *
1438
1439gcc needs to closely track the operating system release to avoid
1440build problems. If Configure finds that gcc was built for a different
1441operating system release than is running, it now gives a clearly visible
1442warning that there may be trouble ahead.
1443
1444=item *
1445
1446If binary compatibility with the 5.005 release is not wanted, Configure
1447no longer suggests including the 5.005 modules in @INC.
1448
1449=item *
1450
1451Configure C<-S> can now run non-interactively.
1452
1453=item *
1454
44da0e71
JH
1455Configure support for pdp11-style memory models has been removed due
1456to obsolescence.
1457
1458=item *
1459
77c8cf41 1460configure.gnu now works with options with whitespace in them.
f39f21d8 1461
77c8cf41 1462=item *
f39f21d8 1463
77c8cf41 1464installperl now outputs everything to STDERR.
f39f21d8 1465
77c8cf41
JH
1466=item *
1467
1468$Config{byteorder} is now computed dynamically (this is more robust
1469with "fat binaries" where an executable image contains binaries for
1470more than one binary platform.)
f39f21d8
JH
1471
1472=item *
1473
1474Because PerlIO is now the default on most platforms, "-perlio" doesn't
1475get appended to the $Config{archname} (also known as $^O) anymore.
1476Instead, if you explicitly choose not to use perlio (Configure command
1477line option -Uuseperlio), you will get "-stdio" appended.
1478
1479=item *
1480
1481Another change related to the architecture name is that "-64all"
1482(-Duse64bitall, or "maximally 64-bit") is appended only if your
1483pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
1484
1485=item *
1486
77c8cf41
JH
1487In AFS installations one can configure the root of the AFS to be
1488somewhere else than the default F</afs> by using the Configure
1489parameter C<-Dafsroot=/some/where/else>.
1490
1491=item *
1492
61947107
JH
1493APPLLIB_EXP, a less-know configuration-time definition, has been
1494documented. It can be used to prepend site-specific directories
1495to Perl's default search path (@INC), see INSTALL for information.
1496
1497=item *
1498
77c8cf41
JH
1499The version of Berkeley DB used when the Perl (and, presumably, the
1500DB_File extension) was built is now available as
1501C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
1502from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
1503DB_VERSION_PATCH_CFG> from C.
1504
1505=item *
1506
61947107
JH
1507Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
1508has been documented in INSTALL.
77c8cf41
JH
1509
1510=item *
1511
61947107
JH
1512If you have CPAN access (either network or a local copy such as a
1513CD-ROM) you can during specify extra modules to Configure to build and
1514install with Perl using the -Dextras=... option. See INSTALL for
1515more details.
f39f21d8 1516
61947107 1517=item *
f39f21d8 1518
61947107
JH
1519In addition to config.over a new override file, config.arch, is
1520available. That is supposed to be used by hints file writers for
1521architecture-wide changes (as opposed to config.over which is for
1522site-wide changes).
f39f21d8
JH
1523
1524=item *
1525
e1f170bd
JH
1526If your file system supports symbolic links you can build Perl outside
1527of the source directory by
1528
1529 mkdir /tmp/perl/build/directory
1530 cd /tmp/perl/build/directory
1531 sh /path/to/perl/source/Configure -Dmksymlinks ...
1532
1533This will create in /tmp/perl/build/directory a tree of symbolic links
1534pointing to files in /path/to/perl/source. The original files are left
1535unaffected. After Configure has finished you can just say
1536
1537 make all test
1538
1539and Perl will be built and tested, all in /tmp/perl/build/directory.
1540
1541=item *
1542
61947107
JH
1543For Perl developers several new make targets for profiling
1544and debugging have been added, see L<perlhack>.
1545
1546=over 8
f39f21d8
JH
1547
1548=item *
1549
61947107
JH
1550Use of the F<gprof> tool to profile Perl has been documented in
1551L<perlhack>. There is a make target called "perl.gprof" for
1552generating a gprofiled Perl executable.
f39f21d8
JH
1553
1554=item *
1555
61947107
JH
1556If you have GCC 3, there is a make target called "perl.gcov" for
1557creating a gcoved Perl executable for coverage analysis. See
1558L<perlhack>.
f39f21d8
JH
1559
1560=item *
1561
61947107
JH
1562If you are on IRIX or Tru64 platforms, new profiling/debugging options
1563have been added, see L<perlhack> for more information about pixie and
1564Third Degree.
1565
1566=back
f39f21d8
JH
1567
1568=item *
1569
61947107
JH
1570Guidelines of how to construct minimal Perl installations have
1571been added to INSTALL.
f39f21d8
JH
1572
1573=item *
1574
61947107
JH
1575The Thread extension is now not built at all under ithreads
1576(C<Configure -Duseithreads>) because it wouldn't work anyway (the
1577Thread extension requires being Configured with C<-Duse5005threads>).
f39f21d8 1578
61947107
JH
1579But note that the Thread.pm interface is now shared by both
1580thread models.
f39f21d8 1581
61947107 1582=back
f39f21d8 1583
61947107 1584=head2 New Or Improved Platforms
f39f21d8 1585
61947107
JH
1586For the list of platforms known to support Perl,
1587see L<perlport/"Supported Platforms">.
1588
1589=over 4
f39f21d8
JH
1590
1591=item *
1592
61947107 1593AIX dynamic loading should be now better supported.
f39f21d8 1594
f39f21d8
JH
1595=item *
1596
77c8cf41
JH
1597AIX should now work better with gcc, threads, and 64-bitness. Also the
1598long doubles support in AIX should be better now. See L<perlaix>.
f39f21d8
JH
1599
1600=item *
1601
61947107
JH
1602After a long pause, AmigaOS has been verified to be happy with Perl.
1603
1604=item *
1605
77c8cf41 1606AtheOS (http://www.atheos.cx/) is a new platform.
f39f21d8 1607
77c8cf41 1608=item *
f39f21d8 1609
58175c9b
JH
1610BeOS has been reclaimed.
1611
1612=item *
1613
77c8cf41 1614DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
f39f21d8
JH
1615
1616=item *
1617
77c8cf41 1618DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
f39f21d8
JH
1619
1620=item *
1621
61947107
JH
1622EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
1623have been regained. Many test suite tests still fail and the
1624co-existence of Unicode and EBCDIC isn't quite settled, but the
1625situation is much better than with Perl 5.6. See L<perlos390>,
1626L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
f39f21d8
JH
1627
1628=item *
1629
61947107
JH
1630Building perl with -Duseithreads or -Duse5005threads now works under
1631HP-UX 10.20 (previously it only worked under 10.30 or later). You will
1632need a thread library package installed. See README.hpux.
f39f21d8 1633
77c8cf41 1634=item *
f39f21d8 1635
61947107
JH
1636MacOS Classic (MacPerl has of course been available since
1637perl 5.004 but now the source code bases of standard Perl
1638and MacPerl have been synchronised)
f39f21d8 1639
77c8cf41 1640=item *
f39f21d8 1641
61947107
JH
1642MacOS X (or Darwin) should now be able to build Perl even on HFS+
1643filesystems. (The case-insensitivity confused the Perl build process.)
f39f21d8 1644
888aee59
JH
1645=item *
1646
61947107 1647NCR MP-RAS is now supported.
888aee59
JH
1648
1649=item *
1650
58175c9b
JH
1651All the NetBSD specific patches (except for the installation
1652specific ones) have been merged back to the main distribution.
1653
1654=item *
1655
61947107 1656NetWare from Novell is now supported. See L<perlnetware>.
888aee59
JH
1657
1658=item *
1659
61947107 1660NonStop-UX is now supported.
888aee59
JH
1661
1662=item *
1663
44da0e71
JH
1664NEC SUPER-UX is now supported.
1665
1666=item *
1667
58175c9b
JH
1668All the OpenBSD specific patches (except for the installation
1669specific ones) have been merged back to the main distribution.
1670
1671=item *
1672
1673Perl has been tested with the GNU pth userlevel thread package
1674( http://www.gnu.org/software/pth/pth.html ) . All but one thread
1675test worked, and that one failure was because of test results arriving
1676in unexpected order.
1677
1678=item *
1679
61947107 1680Amdahl UTS UNIX mainframe platform is now supported.
888aee59
JH
1681
1682=item *
1683
61947107
JH
1684WinCE is now supported. See L<perlce>.
1685
1686=item *
1687
1688z/OS (formerly known as OS/390, formerly known as MVS OE) has now
1689support for dynamic loading. This is not selected by default,
1690however, you must specify -Dusedl in the arguments of Configure.
888aee59 1691
f39f21d8
JH
1692=back
1693
1694=head1 Selected Bug Fixes
1695
e1f170bd
JH
1696Numerous memory leaks and uninitialized memory accesses have been
1697hunted down. Most importantly anonymous subs used to leak quite
1698a bit.
ba370e9b 1699
f39f21d8
JH
1700=over 4
1701
1702=item *
1703
e1f170bd 1704The autouse pragma didn't work for Multi::Part::Function::Names.
f39f21d8
JH
1705
1706=item *
1707
44da0e71
JH
1708caller() could cause core dumps in certain situations. Carp was sometimes
1709affected by this problem.
1710
1711=item *
1712
e1f170bd
JH
1713chop(@list) in list context returned the characters chopped in
1714reverse order. This has been reversed to be in the right order.
f39f21d8
JH
1715
1716=item *
1717
e1f170bd
JH
1718Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
1719when building the Perl binary. The only exception to this is SunOS 4.x,
1720which needs them.
f39f21d8
JH
1721
1722=item *
1723
e1f170bd
JH
1724The behaviour of non-decimal but numeric string constants such as
1725"0x23" was platform-dependent: in some platforms that was seen as 35,
1726in some as 0, in some as a floating point number (don't ask). This
1727was caused by Perl using the operating system libraries in a situation
1728where the result of the string to number conversion is undefined: now
1729Perl consistently handles such strings as zero in numeric contexts.
f39f21d8
JH
1730
1731=item *
1732
e1f170bd 1733The order of DESTROYs has been made more predictable.
f39f21d8
JH
1734
1735=item *
1736
e1f170bd
JH
1737Several debugger fixes: exit code now reflects the script exit code,
1738condition C<"0"> now treated correctly, the C<d> command now checks
44da0e71
JH
1739line number, the C<$.> no longer gets corrupted, all debugger output
1740now goes correctly to the socket if RemotePort is set.
1741
1742=item *
1743
1744Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
1745when statically building extensions into perl. This has been corrected.
f39f21d8
JH
1746
1747=item *
1748
e1f170bd 1749L<dprofpp> -R didn't work.
f39f21d8
JH
1750
1751=item *
1752
e1f170bd 1753C<*foo{FORMAT}> now works.
44da0e71
JH
1754=item *
1755
1756Infinity is now recognized as a number.
f39f21d8
JH
1757
1758=item *
1759
e1f170bd
JH
1760UNIVERSAL::isa no longer caches methods incorrectly. (This broke
1761the Tk extension with 5.6.0.)
f39f21d8
JH
1762
1763=item *
1764
e1f170bd
JH
1765Lexicals I: lexicals outside an eval "" weren't resolved
1766correctly inside a subroutine definition inside the eval "" if they
1767were not already referenced in the top level of the eval""ed code.
f39f21d8
JH
1768
1769=item *
1770
e1f170bd
JH
1771Lexicals II: lexicals leaked at file scope into subroutines that
1772were declared before the lexicals.
f39f21d8
JH
1773
1774=item *
1775
44da0e71
JH
1776Lexical warnings now propagating correctly between scopes
1777and into C<eval "...">.
1778
1779=item *
1780
1781C<use warnings qw(FATAL all)> did not work as intended. This has been
1782corrected.
1783
1784=item *
1785
1786warnings::enabled() now reports the state of $^W correctly if the caller
1787isn't using lexical warnings.
f39f21d8
JH
1788
1789=item *
1790
e1f170bd 1791Line renumbering with eval and C<#line> now works.
f39f21d8
JH
1792
1793=item *
1794
e1f170bd 1795Fixed numerous memory leaks, especially in eval "".
f39f21d8
JH
1796
1797=item *
1798
e1f170bd
JH
1799mkdir() now ignores trailing slashes in the directory name,
1800as mandated by POSIX.
f39f21d8
JH
1801
1802=item *
1803
e1f170bd
JH
1804Some versions of glibc have a broken modfl(). This affects builds
1805with C<-Duselongdouble>. This version of Perl detects this brokenness
1806and has a workaround for it. The glibc release 2.2.2 is known to have
1807fixed the modfl() bug.
f39f21d8
JH
1808
1809=item *
1810
e1f170bd
JH
1811Modulus of unsigned numbers now works (4063328477 % 65535 used to
1812return 27406, instead of 27047).
f39f21d8
JH
1813
1814=item *
1815
e1f170bd
JH
1816Some "not a number" warnings introduced in 5.6.0 eliminated to be
1817more compatible with 5.005. Infinity is now recognised as a number.
f39f21d8 1818
77c8cf41 1819=item *
f39f21d8 1820
44da0e71
JH
1821Numeric conversions did not recognize changes in the string value
1822properly in certain circumstances.
1823
1824=item *
1825
e1f170bd 1826Attributes (like :shared) didn't work with our().
f39f21d8
JH
1827
1828=item *
1829
e1f170bd 1830our() variables will not cause "will not stay shared" warnings.
f39f21d8
JH
1831
1832=item *
1833
44da0e71
JH
1834"our" variables of the same name declared in two sibling blocks
1835resulted in bogus warnings about "redeclaration" of the variables.
1836The problem has been corrected.
1837
1838=item *
1839
e1f170bd 1840pack "Z" now correctly terminates the string with "\0".
f39f21d8
JH
1841
1842=item *
1843
e1f170bd
JH
1844Fix password routines which in some shadow password platforms
1845(e.g. HP-UX) caused getpwent() to return every other entry.
f39f21d8 1846
77c8cf41 1847=item *
f39f21d8 1848
e1f170bd
JH
1849The PERL5OPT environment variable (for passing command line arguments
1850to Perl) didn't work for more than a single group of options.
f39f21d8 1851
77c8cf41 1852=item *
f39f21d8 1853
e1f170bd 1854PERL5OPT with embedded spaces didn't work.
f39f21d8 1855
77c8cf41 1856=item *
f39f21d8 1857
e1f170bd 1858printf() no longer resets the numeric locale to "C".
f39f21d8 1859
77c8cf41 1860=item *
f39f21d8 1861
44da0e71
JH
1862C<qw(a\\b)> now parses correctly as C<'a\\b'>.
1863
1864=item *
1865
1866pos() did not return the correct value within s///ge in earlier
1867versions. This is now handled correctly.
f39f21d8 1868
77c8cf41 1869=item *
f39f21d8 1870
e1f170bd
JH
1871Printing quads (64-bit integers) with printf/sprintf now works
1872without the q L ll prefixes (assuming you are on a quad-capable platform).
f39f21d8 1873
77c8cf41 1874=item *
f39f21d8 1875
e1f170bd 1876Regular expressions on references and overloaded scalars now work.
f39f21d8 1877
ba370e9b
JH
1878=item *
1879
e1f170bd
JH
1880Right-hand side magic (GMAGIC) could in many cases such as string
1881concatenation be invoked too many times.
ba370e9b
JH
1882
1883=item *
1884
e1f170bd 1885scalar() now forces scalar context even when used in void context.
ba370e9b
JH
1886
1887=item *
1888
e1f170bd 1889SOCKS support is now much more robust.
ba370e9b
JH
1890
1891=item *
1892
e1f170bd
JH
1893sort() arguments are now compiled in the right wantarray context
1894(they were accidentally using the context of the sort() itself).
44da0e71
JH
1895The comparison block is now run in scalar context, and the arguments
1896to be sorted are always provided list context.
ba370e9b
JH
1897
1898=item *
1899
e1f170bd 1900Changed the POSIX character class C<[[:space:]]> to include the (very
c2e23569
JH
1901rarely used) vertical tab character. Added a new POSIX-ish character
1902class C<[[:blank:]]> which stands for horizontal whitespace
1903(currently, the space and the tab).
ba370e9b
JH
1904
1905=item *
1906
1907The tainting behaviour of sprintf() has been rationalized. It does
1908not taint the result of floating point formats anymore, making the
1909behaviour consistent with that of string interpolation.
1910
1911=item *
1912
44da0e71
JH
1913Some cases of inconsistent taint propagation (such as within hash
1914values) have been fixed.
1915
1916=item *
1917
1918The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
1919of simple pattern matches. These are now handled better.
1920
1921=item *
1922
1923Regular expression debug output (whether through C<use re 'debug'>
1924or via C<-Dr>) now looks better.
1925
1926=item *
1927
1928Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
1929bug has been fixed.
1930
1931=item *
1932
1933Use of $& could trigger a core dump under some situations. This
1934is now avoided.
1935
1936=item *
1937
c2e23569
JH
1938The regular expression captured submatches ($1, $2, ...) are now
1939more consistently unset if the match fails, instead of leaving false
1940data lying around in them.
1941
1942=item *
1943
44da0e71
JH
1944readline() on files opened in "slurp" mode could return an extra "" at
1945the end in certain situations. This has been corrected.
1946
1947=item *
1948
1949Autovivification of symbolic references of special variables described
1950in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
1951again now.
1952
1953=item *
1954
da6838c8 1955Sys::Syslog ignored the C<LOG_AUTH> constant.
ba370e9b
JH
1956
1957=item *
1958
e1f170bd 1959All but the first argument of the IO syswrite() method are now optional.
ba370e9b
JH
1960
1961=item *
1962
e1f170bd
JH
1963$AUTOLOAD, sort(), lock(), and spawning subprocesses
1964in multiple threads simultaneously are now thread-safe.
ba370e9b
JH
1965
1966=item *
1967
e1f170bd 1968Tie::ARRAY SPLICE method was broken.
ba370e9b
JH
1969
1970=item *
1971
e1f170bd 1972Allow read-only string on left hand side of non-modifying tr///.
ba370e9b
JH
1973
1974=item *
1975
e1f170bd 1976Several Unicode fixes.
ba370e9b
JH
1977
1978=over 8
1979
1980=item *
1981
e1f170bd
JH
1982BOMs (byte order marks) in the beginning of Perl files
1983(scripts, modules) should now be transparently skipped.
1984UTF-16 (UCS-2) encoded Perl files should now be read correctly.
ba370e9b
JH
1985
1986=item *
1987
e1f170bd 1988The character tables have been updated to Unicode 3.1.1.
ba370e9b
JH
1989
1990=item *
1991
e1f170bd 1992Comparing with utf8 data does not magically upgrade non-utf8 data
58175c9b
JH
1993into utf8. (This was a problem for example if you were mixing data
1994from I/O and Unicode data: your output might have got magically encoded
1995as UTF-8.)
1996
1997=item *
1998
1999Generating illegal Unicode code points like U+FFFE, or the UTF-16
2000surrogates, now also generates an optional warning.
ba370e9b
JH
2001
2002=item *
2003
e1f170bd 2004C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
f39f21d8 2005
77c8cf41 2006=item *
f39f21d8 2007
e1f170bd
JH
2008Concatenation with the C<.> operator or via variable interpolation,
2009C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
2010substitution with C<s///>, single-quoted UTF8, should now work.
f39f21d8 2011
77c8cf41 2012=item *
f39f21d8 2013
e1f170bd
JH
2014The C<tr///> operator now works. Note that the C<tr///CU>
2015functionality has been removed (but see pack('U0', ...)).
f39f21d8 2016
77c8cf41 2017=item *
f39f21d8 2018
e1f170bd 2019C<eval "v200"> now works.
f39f21d8 2020
77c8cf41 2021=item *
f39f21d8 2022
44da0e71
JH
2023Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
2024This has been corrected.
2025
2026=item *
2027
e1f170bd 2028Zero entries were missing from the Unicode classes like C<IsDigit>.
f39f21d8 2029
e1f170bd 2030=back
f39f21d8 2031
44da0e71
JH
2032=item *
2033
2034Large unsigned numbers (those above 2**31) could sometimes lose their
2035unsignedness, causing bogus results in arithmetic operations.
2036
77c8cf41 2037=back
f39f21d8 2038
77c8cf41 2039=head2 Platform Specific Changes and Fixes
f39f21d8
JH
2040
2041=over 4
2042
2043=item *
2044
77c8cf41 2045BSDI 4.*
f39f21d8 2046
77c8cf41 2047Perl now works on post-4.0 BSD/OSes.
f39f21d8
JH
2048
2049=item *
2050
77c8cf41 2051All BSDs
f39f21d8 2052
057b7f2b 2053Setting C<$0> now works (as much as possible; see L<perlvar> for details).
f39f21d8
JH
2054
2055=item *
2056
77c8cf41 2057Cygwin
f39f21d8 2058
77c8cf41 2059Numerous updates; currently synchronised with Cygwin 1.1.4.
f39f21d8
JH
2060
2061=item *
2062
e1f170bd
JH
2063Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
2064
2065=item *
2066
77c8cf41 2067EPOC
f39f21d8 2068
77c8cf41 2069EPOC update after Perl 5.6.0. See README.epoc.
f39f21d8
JH
2070
2071=item *
2072
77c8cf41 2073FreeBSD 3.*
f39f21d8 2074
77c8cf41 2075Perl now works on post-3.0 FreeBSDs.
f39f21d8
JH
2076
2077=item *
2078
77c8cf41
JH
2079HP-UX
2080
2081README.hpux updated; C<Configure -Duse64bitall> now almost works.
f39f21d8
JH
2082
2083=item *
2084
77c8cf41 2085IRIX
f39f21d8 2086
77c8cf41
JH
2087Numerous compilation flag and hint enhancements; accidental mixing
2088of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
f39f21d8 2089
77c8cf41 2090=item *
f39f21d8 2091
77c8cf41 2092Linux
f39f21d8 2093
e1f170bd
JH
2094=over 8
2095
2096=item *
2097
77c8cf41 2098Long doubles should now work (see INSTALL).
f39f21d8
JH
2099
2100=item *
2101
e1f170bd
JH
2102Linux previously had problems related to sockaddrlen when using
2103accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
2104
2105=back
2106
2107=item *
2108
77c8cf41 2109MacOS Classic
f39f21d8 2110
77c8cf41
JH
2111Compilation of the standard Perl distribution in MacOS Classic should
2112now work if you have the Metrowerks development environment and
2113the missing Mac-specific toolkit bits. Contact the macperl mailing
2114list for details.
f39f21d8
JH
2115
2116=item *
2117
77c8cf41 2118MPE/iX
f39f21d8 2119
77c8cf41 2120MPE/iX update after Perl 5.6.0. See README.mpeix.
f39f21d8
JH
2121
2122=item *
2123
77c8cf41 2124NetBSD/sparc
f39f21d8 2125
77c8cf41 2126Perl now works on NetBSD/sparc.
f39f21d8
JH
2127
2128=item *
2129
77c8cf41 2130OS/2
f39f21d8 2131
77c8cf41 2132Now works with usethreads (see INSTALL).
f39f21d8
JH
2133
2134=item *
2135
77c8cf41 2136Solaris
f39f21d8 2137
77c8cf41 213864-bitness using the Sun Workshop compiler now works.
f39f21d8
JH
2139
2140=item *
2141
77c8cf41 2142Tru64 (aka Digital UNIX, aka DEC OSF/1)
f39f21d8 2143
77c8cf41
JH
2144The operating system version letter now recorded in $Config{osvers}.
2145Allow compiling with gcc (previously explicitly forbidden). Compiling
2146with gcc still not recommended because buggy code results, even with
2147gcc 2.95.2.
f39f21d8
JH
2148
2149=item *
2150
77c8cf41
JH
2151Unicos
2152
2153Fixed various alignment problems that lead into core dumps either
2154during build or later; no longer dies on math errors at runtime;
2155now using full quad integers (64 bits), previously was using
2156only 46 bit integers for speed.
f39f21d8
JH
2157
2158=item *
2159
77c8cf41
JH
2160VMS
2161
2162chdir() now works better despite a CRT bug; now works with MULTIPLICITY
2163(see INSTALL); now works with Perl's malloc.
f39f21d8 2164
00bb525a
CB
2165The tainting of C<%ENV> elements via C<keys> or C<values> was previously
2166unimplemented. It now works as documented.
2167
2168The C<waitpid> emulation has been improved. The worst bug (now fixed)
2169was that a pid of -1 would cause a wildcard search of all processes on
2170the system. The most significant enhancement is that we can now
2171usually get the completion status of a terminated process.
2172
2173POSIX-style signals are now emulated much better on VMS versions prior
2174to 7.0.
2175
2176The C<system> function and backticks operator have improved
2177functionality and better error handling.
2178
161720b2
CB
2179File access tests now use current process privileges rather than the
2180user's default privileges, which could sometimes result in a mismatch
2181between reported access and actual access.
2182
f39f21d8
JH
2183=item *
2184
77c8cf41 2185Windows
f39f21d8 2186
77c8cf41 2187=over 8
f39f21d8
JH
2188
2189=item *
2190
77c8cf41 2191accept() no longer leaks memory.
f39f21d8
JH
2192
2193=item *
2194
e1f170bd
JH
2195Borland C++ v5.5 is now a supported compiler that can build Perl.
2196However, the generated binaries continue to be incompatible with those
2197generated by the other supported compilers (GCC and Visual C++).
2198
2199=item *
2200
77c8cf41 2201Better chdir() return value for a non-existent directory.
f39f21d8 2202
77c8cf41 2203=item *
f39f21d8 2204
e1f170bd
JH
2205Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
2206
2207=item *
2208
77c8cf41 2209New %ENV entries now propagate to subprocesses.
f39f21d8
JH
2210
2211=item *
2212
44da0e71
JH
2213Current directory entries in %ENV are now correctly propagated to child
2214processes.
2215
2216=item *
2217
77c8cf41
JH
2218$ENV{LIB} now used to search for libs under Visual C.
2219
2220=item *
2221
44da0e71
JH
2222fork() emulation has been improved in various ways, but still continues
2223to be experimental. See L<perlfork> for known bugs and caveats.
e1f170bd
JH
2224
2225=item *
2226
77c8cf41 2227A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
f39f21d8
JH
2228
2229=item *
2230
44da0e71
JH
2231Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
2232Other bugs in chdir() and Cwd::cwd() have also been fixed.
2233
2234=item *
2235
e1f170bd
JH
2236HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
2237
2238=item *
2239
2240The makefiles now provide a single switch to bulk-enable all the features
2241enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
2242
2243=item *
2244
77c8cf41 2245Allow REG_EXPAND_SZ keys in the registry.
f39f21d8
JH
2246
2247=item *
2248
77c8cf41 2249Can now send() from all threads, not just the first one.
f39f21d8
JH
2250
2251=item *
2252
77c8cf41 2253Fake signal handling reenabled, bugs and all.
f39f21d8
JH
2254
2255=item *
2256
44da0e71
JH
2257%SIG has been enabled under USE_ITHREADS, but its use is completely
2258unsupported under all configurations.
2259
2260=item *
2261
77c8cf41
JH
2262Less stack reserved per thread so that more threads can run
2263concurrently. (Still 16M per thread.)
f39f21d8
JH
2264
2265=item *
2266
c2e23569 2267C<File::Spec-&gt;tmpdir()> now prefers C:/temp over /tmp
77c8cf41 2268(works better when perl is running as service).
f39f21d8
JH
2269
2270=item *
2271
77c8cf41 2272Better UNC path handling under ithreads.
f39f21d8
JH
2273
2274=item *
2275
44da0e71
JH
2276wait(), waitpid() and backticks now return the correct exit status under
2277Windows 9x.
f39f21d8
JH
2278
2279=item *
2280
77c8cf41 2281winsock handle leak fixed.
f39f21d8
JH
2282
2283=back
2284
77c8cf41 2285=back
f39f21d8 2286
77c8cf41 2287=head1 New or Changed Diagnostics
f39f21d8 2288
ba370e9b
JH
2289=over 4
2290
2291=item *
2292
12bcd1a6
PM
2293The lexical warnings category "deprecated" is no longer a sub-category
2294of the "syntax" category. It is now a top-level category in its own
2295right.
2296
2297=item *
2298
77c8cf41
JH
2299All regular expression compilation error messages are now hopefully
2300easier to understand both because the error message now comes before
2301the failed regex and because the point of failure is now clearly
ba370e9b
JH
2302marked by a C<E<lt>-- HERE> marker.
2303
2304=item *
f39f21d8 2305
77c8cf41
JH
2306The various "opened only for", "on closed", "never opened" warnings
2307drop the C<main::> prefix for filehandles in the C<main> package,
bea4d472 2308for example C<STDIN> instead of C<main::STDIN>.
f39f21d8 2309
ba370e9b
JH
2310=item *
2311
77c8cf41
JH
2312The "Unrecognized escape" warning has been extended to include C<\8>,
2313C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
f39f21d8 2314
ba370e9b 2315=item *
f39f21d8 2316
77c8cf41
JH
2317Two new debugging options have been added: if you have compiled your
2318Perl with debugging, you can use the -DT and -DR options to trace
2319tokenising and to add reference counts to displaying variables,
2320respectively.
f39f21d8
JH
2321
2322=item *
2323
492652be
RF
2324perl5db.pl has been modified to present a more consistent commands
2325interface, via (CommandSet=580). perl5db.t was also added to test the
2326changes, and as a placeholder for further tests.
2327
2328See L<perldebug>
2329
2330=item *
2331
77c8cf41
JH
2332If an attempt to use a (non-blessed) reference as an array index
2333is made, a warning is given.
f39f21d8
JH
2334
2335=item *
2336
77c8cf41
JH
2337C<push @a;> and C<unshift @a;> (with no values to push or unshift)
2338now give a warning. This may be a problem for generated and evaled
2339code.
f39f21d8 2340
ba370e9b
JH
2341=item *
2342
2343If you try to L<perlfunc/pack> a number less than 0 or larger than 255
2344using the C<"C"> format you will get an optional warning. Similarly
2345for the C<"c"> format and a number less than -128 or more than 127.
2346
2347=item *
2348
2349Certain regex modifiers such as C<(?o)> make sense only if applied to
2350the entire regex. You will an optional warning if you try to do otherwise.
2351
2352=item *
2353
c2e23569
JH
2354Using arrays or hashes as references (e.g. C<< %foo-&gt;{bar} >>
2355has been deprecated for a while. Now you will get an optional warning.
ba370e9b 2356
f39f21d8
JH
2357=back
2358
77c8cf41 2359=head1 Changed Internals
f39f21d8
JH
2360
2361=over 4
2362
2363=item *
2364
77c8cf41
JH
2365perlapi.pod (a companion to perlguts) now attempts to document the
2366internal API.
f39f21d8
JH
2367
2368=item *
2369
77c8cf41
JH
2370You can now build a really minimal perl called microperl.
2371Building microperl does not require even running Configure;
2372C<make -f Makefile.micro> should be enough. Beware: microperl makes
2373many assumptions, some of which may be too bold; the resulting
2374executable may crash or otherwise misbehave in wondrous ways.
2375For careful hackers only.
f39f21d8
JH
2376
2377=item *
2378
c2e23569
JH
2379Added rsignal(), whichsig(), do_join(), op_clear, op_null,
2380ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
2381interfaces to the publicised API. For the full list of the available
2382APIs see L<perlapi>.
f39f21d8
JH
2383
2384=item *
2385
77c8cf41 2386Made possible to propagate customised exceptions via croak()ing.
f39f21d8 2387
77c8cf41 2388=item *
f39f21d8 2389
95f0a2f1
SB
2390Now xsubs can have attributes just like subs. (Well, at least the
2391built-in attributes.)
f39f21d8
JH
2392
2393=item *
2394
77c8cf41
JH
2395dTHR and djSP have been obsoleted; the former removed (because it's
2396a no-op) and the latter replaced with dSP.
f39f21d8
JH
2397
2398=item *
2399
61947107
JH
2400PERL_OBJECT has been completely removed.
2401
2402=item *
2403
ba370e9b
JH
2404The MAGIC constants (e.g. C<'P'>) have been macrofied
2405(e.g. C<PERL_MAGIC_TIED>) for better source code readability
2406and maintainability.
2407
2408=item *
2409
2410The regex compiler now maintains a structure that identifies nodes in
2411the compiled bytecode with the corresponding syntactic features of the
2412original regex expression. The information is attached to the new
2413C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
2414complete information.
2415
2416=item *
2417
2418The C code has been made much more C<gcc -Wall> clean. Some warning
2419messages still remain in some platforms, so if you are compiling with
2420gcc you may see some warnings about dubious practices. The warnings
2421are being worked on.
2422
2423=item *
2424
2425F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
2426
2427=item *
2428
61947107
JH
2429Documentation on how to use the Perl source repository has been added
2430to F<Porting/repository.pod>.
f39f21d8 2431
888aee59
JH
2432=item *
2433
c2e23569 2434There are now several profiling make targets.
888aee59 2435
77c8cf41 2436=back
f39f21d8 2437
77c8cf41 2438=head1 Security Vulnerability Closed
f39f21d8 2439
77c8cf41 2440(This change was already made in 5.7.0 but bears repeating here.)
f39f21d8 2441
77c8cf41
JH
2442A potential security vulnerability in the optional suidperl component
2443of Perl was identified in August 2000. suidperl is neither built nor
2444installed by default. As of November 2001 the only known vulnerable
2445platform is Linux, most likely all Linux distributions. CERT and
2446various vendors and distributors have been alerted about the vulnerability.
2447See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
2448for more information.
f39f21d8 2449
77c8cf41
JH
2450The problem was caused by Perl trying to report a suspected security
2451exploit attempt using an external program, /bin/mail. On Linux
2452platforms the /bin/mail program had an undocumented feature which
2453when combined with suidperl gave access to a root shell, resulting in
2454a serious compromise instead of reporting the exploit attempt. If you
2455don't have /bin/mail, or if you have 'safe setuid scripts', or if
2456suidperl is not installed, you are safe.
f39f21d8 2457
77c8cf41
JH
2458The exploit attempt reporting feature has been completely removed from
2459Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
2460from all the Perl 5.7 releases), so that particular vulnerability
2461isn't there anymore. However, further security vulnerabilities are,
ba370e9b
JH
2462unfortunately, always possible. The suidperl functionality is most
2463probably going to be removed in Perl 5.10. In any case, suidperl
2464should only be used by security experts who know exactly what they are
2465doing and why they are using suidperl instead of some other solution
2466such as sudo (see http://www.courtesan.com/sudo/).
77c8cf41
JH
2467
2468=head1 New Tests
2469
76663d67
JH
2470Several new tests have been added, especially for the F<lib>
2471subsection. There are now about 34 000 individual tests (spread over
2472about 530 test scripts), in the regression suite (5.6.1 has about
247311700 tests, in 258 test scripts) Many of the new tests are introduced
2474by the new modules, but still in general Perl is now more thoroughly
2475tested.
2476
2477Because of the large number of tests, running the regression suite
2478will take considerably longer time than it used to: expect the suite
2479to take up to 4-5 times longer to run than in perl 5.6. In a really
2480fast machine you can hope to finish the suite in about 5 minutes
2481(wallclock time).
77c8cf41
JH
2482
2483The tests are now reported in a different order than in earlier Perls.
2484(This happens because the test scripts from under t/lib have been moved
2485to be closer to the library/extension they are testing.)
2486
f39f21d8
JH
2487=head1 Known Problems
2488
f39f21d8
JH
2489=head2 AIX
2490
2491=over 4
2492
2493=item *
2494
2495In AIX 4.2 Perl extensions that use C++ functions that use statics
2496may have problems in that the statics are not getting initialized.
2497In newer AIX releases this has been solved by linking Perl with
2498the libC_r library, but unfortunately in AIX 4.2 the said library
2499has an obscure bug where the various functions related to time
2500(such as time() and gettimeofday()) return broken values, and
2501therefore in AIX 4.2 Perl is not linked against the libC_r.
2502
2503=item *
2504
2505vac 5.0.0.0 May Produce Buggy Code For Perl
2506
2507The AIX C compiler vac version 5.0.0.0 may produce buggy code,
2508resulting in few random tests failing, but when the failing tests
2509are run by hand, they succeed. We suggest upgrading to at least
2510vac version 5.0.1.0, that has been known to compile Perl correctly.
2511"lslpp -L|grep vac.C" will tell you the vac version.
2512
2513=back
2514
2515=head2 Amiga Perl Invoking Mystery
2516
2517One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
057b7f2b 2518works, but for example C<bin:perl -v> doesn't. The exact reason isn't
f39f21d8
JH
2519known but the current suspect is the F<ixemul> library.
2520
2521=head2 lib/ftmp-security tests warn 'system possibly insecure'
2522
2523Don't panic. Read INSTALL 'make test' section instead.
2524
2525=head2 Cygwin intermittent failures of lib/Memoize/t/expire_file 11 and 12
2526
2527The subtests 11 and 12 sometimes fail and sometimes work.
2528
ef985a5e
NC
2529=head2 FreeBSD 4.5 fails lib/File/Spec/t/rel2abs2rel.t
2530
fb6d9fa6
NC
2531F<lib/File/Spec/t/rel2abs2rel.t> tests that "`` works" by running a
2532a perl 1 liner in backticks, using "$^X" as the path to perl.
ef985a5e
NC
2533It is failing on FreeBSD 4.5, but only when run as part of make test.
2534This seems to be a kernel problem rather than perl - reading the symlink
2535F</proc/curproc/file> returns "unknown" rather than the path to perl, and a
2536kernel debugger reveals that variable C<numfullpathfail2> in
fb6d9fa6 2537F</usr/src/sys/kern/vfs_cache.c> is being incremented whenever
ef985a5e
NC
2538F</proc/curproc/file> fails to return the perl executable's path.
2539
f39f21d8
JH
2540=head2 HP-UX lib/io_multihomed Fails When LP64-Configured
2541
2542The lib/io_multihomed test may hang in HP-UX if Perl has been
2543configured to be 64-bit. Because other 64-bit platforms do not hang in
2544this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
2545test attempts to create and connect to "multihomed" sockets (sockets
2546which have multiple IP addresses).
2547
2548=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
2549
2550If perl is configured with -Duse64bitall, the successful result of the
2551subtest 10 of lib/posix may arrive before the successful result of the
2552subtest 9, which confuses the test harness so much that it thinks the
2553subtest 9 failed.
2554
2555=head2 Linux With Sfio Fails op/misc Test 48
2556
2557No known fix.
2558
a0aae13b
JH
2559=head2 Mac OS X
2560
2561The following tests are known to fail:
2562
2563 Failed Test Stat Wstat Total Fail Failed List of Failed
2564 -------------------------------------------------------------------------
2565 ../ext/DB_File/t/db-btree.t 0 11 ?? ?? % ??
2566 ../ext/DB_File/t/db-recno.t 149 3 2.01% 61 63 65
2567 ../ext/POSIX/t/posix.t 31 1 3.23% 10
2568 ../lib/warnings.t 450 1 0.22% 316
2569
f39f21d8
JH
2570=head2 OS/390
2571
2572OS/390 has rather many test failures but the situation is actually
2573better than it was in 5.6.0, it's just that so many new modules and
2574tests have been added.
2575
2576 Failed Test Stat Wstat Total Fail Failed List of Failed
2577 -----------------------------------------------------------------------------
2578 ../ext/B/Deparse.t 14 1 7.14% 14
2579 ../ext/B/Showlex.t 1 1 100.00% 1
2580 ../ext/Encode/Encode/Tcl.t 610 13 2.13% 592 594 596 598
2581 600 602 604-610
2582 ../ext/IO/lib/IO/t/io_unix.t 113 28928 5 3 60.00% 3-5
2583 ../ext/POSIX/POSIX.t 29 1 3.45% 14
2584 ../ext/Storable/t/lock.t 255 65280 5 3 60.00% 3-5
2585 ../lib/locale.t 129 33024 117 19 16.24% 99-117
2586 ../lib/warnings.t 434 1 0.23% 75
2587 ../lib/ExtUtils.t 27 1 3.70% 25
2588 ../lib/Math/BigInt/t/bigintpm.t 1190 1 0.08% 1145
2589 ../lib/Unicode/UCD.t 81 48 59.26% 1-16 49-64 66-81
2590 ../lib/User/pwent.t 9 1 11.11% 4
2591 op/pat.t 660 6 0.91% 242-243 424-425
2592 626-627
2593 op/split.t 0 9 ?? ?? % ??
2594 op/taint.t 174 3 1.72% 156 162 168
2595 op/tr.t 70 3 4.29% 50 58-59
2596 Failed 16/422 test scripts, 96.21% okay. 105/23251 subtests failed, 99.55% okay.
2597
2598=head2 op/sprintf tests 129 and 130
2599
2600The op/sprintf tests 129 and 130 are known to fail on some platforms.
2601Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
2602The failing platforms do not comply with the ANSI C Standard, line
260319ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
2604something other than "1" and "-1" when formatting 0.6 and -0.6 using
2605the printf format "%.0f", most often they produce "0" and "-0".)
2606
2607=head2 Failure of Thread tests
2608
fedd8cf1
JH
2609B<Note that support for 5.005-style threading remains experimental
2610and practically unsupported.>
f39f21d8
JH
2611
2612The following tests are known to fail due to fundamental problems in
2613the 5.005 threading implementation. These are not new failures--Perl
26145.005_0x has the same bugs, but didn't have these tests.
2615
fedd8cf1
JH
2616 ext/List/Util/t/first 2
2617 lib/autouse 4
2618 ext/Thread/thr5005 19-20
2619
2620These failures are unlikely to get fixed.
f39f21d8
JH
2621
2622=head2 UNICOS
2623
2624=over 4
2625
2626=item *
2627
2628ext/POSIX/sigaction subtests 6 and 13 may fail.
2629
2630=item *
2631
2632lib/ExtUtils may spuriously claim that subtest 28 failed,
2633which is interesting since the test only has 27 tests.
2634
2635=item *
2636
2637Numerous numerical test failures
2638
2639 op/numconvert 209,210,217,218
2640 op/override 7
2641 ext/Time/HiRes/HiRes 9
2642 lib/Math/BigInt/t/bigintpm 1145
2643 lib/Math/Trig 25
2644
2645These tests fail because of yet unresolved floating point inaccuracies.
2646
2647=back
2648
0968fb3b 2649=head2 UNICOS and UNICOS/mk
0f71e040 2650
0968fb3b
JH
2651The io/fs test #31 is failing because in UNICOS and UNICOS/mk
2652truncate() cannot be used to grow the size of filehandles, only
2653to reduce the size. The workaround is to truncate files instead
2654of filehandles.
0f71e040 2655
f39f21d8
JH
2656=head2 UTS
2657
2658There are a few known test failures, see L<perluts>.
2659
2660=head2 VMS
2661
161720b2
CB
2662There should be no reported test failures with a default configuration,
2663though there are a number of tests marked TODO that point to areas
2664needing further debugging and/or porting work.
7207e29d 2665
f39f21d8
JH
2666=head2 Win32
2667
2668In multi-CPU boxes there are some problems with the I/O buffering:
2669some output may appear twice.
2670
2671=head2 Localising a Tied Variable Leaks Memory
2672
2673 use Tie::Hash;
2674 tie my %tie_hash => 'Tie::StdHash';
2675
2676 ...
2677
2678 local($tie_hash{Foo}) = 1; # leaks
2679
2680Code like the above is known to leak memory every time the local()
2681is executed.
2682
aecce728
JH
2683=head2 Localising Tied Arrays and Hashes Is Broken
2684
2685 local %tied_array;
2686
2687doesn't work as one would expect: the old value is restored
2688incorrectly.
2689
f39f21d8
JH
2690=head2 Self-tying of Arrays and Hashes Is Forbidden
2691
2692Self-tying of arrays and hashes is broken in rather deep and
2693hard-to-fix ways. As a stop-gap measure to avoid people from getting
2694frustrated at the mysterious results (core dumps, most often) it is
2695for now forbidden (you will get a fatal error even from an attempt).
2696
f39f21d8
JH
2697=head2 Building Extensions Can Fail Because Of Largefiles
2698
2699Some extensions like mod_perl are known to have issues with
2700`largefiles', a change brought by Perl 5.6.0 in which file offsets
2701default to 64 bits wide, where supported. Modules may fail to compile
2702at all or compile and work incorrectly. Currently there is no good
2703solution for the problem, but Configure now provides appropriate
2704non-largefile ccflags, ldflags, libswanted, and libs in the %Config
2705hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
2706having problems can try configuring themselves without the
2707largefileness. This is admittedly not a clean solution, and the
2708solution may not even work at all. One potential failure is whether
2709one can (or, if one can, whether it's a good idea) link together at
2710all binaries with different ideas about file offsets, all this is
2711platform-dependent.
2712
aecce728
JH
2713=head2 Unicode Support on EBCDIC Still Spotty
2714
2715Though mostly working, Unicode support still has problem spots on
2716EBCDIC platforms. One such known spot are the C<\p{}> and C<\P{}>
2717regular expression constructs for code points less than 256: the
2718pP are testing for Unicode code points, not knowing about EBCDIC.
2719
f39f21d8
JH
2720=head2 The Compiler Suite Is Still Experimental
2721
44da0e71
JH
2722The compiler suite is slowly getting better but it continues to be
2723highly experimental. Use in production environments is discouraged.
f39f21d8 2724
c4f1ce08 2725=head2 The Long Double Support Is Still Experimental
f39f21d8
JH
2726
2727The ability to configure Perl's numbers to use "long doubles",
2728floating point numbers of hopefully better accuracy, is still
2729experimental. The implementations of long doubles are not yet
2730widespread and the existing implementations are not quite mature
2731or standardised, therefore trying to support them is a rare
2732and moving target. The gain of more precision may also be offset
2733by slowdown in computations (more bits to move around, and the
2734operations are more likely to be executed by less optimised
2735libraries).
33a87e58 2736
c4f1ce08
JH
2737=head2 Seen In Perl 5.7 But Gone Now
2738
c4f1ce08
JH
2739C<Time::Piece> (previously known as C<Time::Object>) was removed
2740because it was felt that it didn't have enough value in it to be a
2741core module. It is still a useful module, though, and is available
2742from the CPAN.
2743
cc0fca54
GS
2744=head1 Reporting Bugs
2745
d4ad863d
JH
2746If you find what you think is a bug, you might check the articles
2747recently posted to the comp.lang.perl.misc newsgroup and the perl
2748bug database at http://bugs.perl.org. There may also be
06a5f41f 2749information at http://www.perl.com/, the Perl Home Page.
cc0fca54
GS
2750
2751If you believe you have an unreported bug, please run the B<perlbug>
2752program included with your release. Be sure to trim your bug down
2753to a tiny but sufficient test case. Your bug report, along with the
d4ad863d 2754output of C<perl -V>, will be sent off to perlbug@perl.org to be
cc0fca54
GS
2755analysed by the Perl porting team.
2756
2757=head1 SEE ALSO
2758
2759The F<Changes> file for exhaustive details on what changed.
2760
2761The F<INSTALL> file for how to build Perl.
2762
2763The F<README> file for general stuff.
2764
2765The F<Artistic> and F<Copying> files for copyright information.
2766
2767=head1 HISTORY
2768
d468ca04 2769Written by Jarkko Hietaniemi <F<jhi@iki.fi>>.
cc0fca54
GS
2770
2771=cut