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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
6123004a 134to be aliases for d/f, but you never knew that.)
79f69e33 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,
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334but the signal may take more time to get heard. Note that breaking
335out from potentially blocking operations should still work, though.
f39f21d8 336
e1f170bd 337=head2 Unicode Overhaul
f39f21d8 338
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339Unicode in general should be now much more usable than in Perl 5.6.0
340(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
341regular expressions should work now, Unicode in tr/// should work now,
342Unicode in I/O should work now.
f39f21d8 343
e1f170bd 344=over 4
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345
346=item *
347
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348The Unicode Character Database coming with Perl has been upgraded
349to Unicode 3.1.1. For more information, see http://www.unicode.org/.
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350
351=item *
352
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353For developers interested in enhancing Perl's Unicode capabilities:
354almost all the UCD files are included with the Perl distribution in
58175c9b 355the F<lib/unicore subdirectory>. The most notable omission, for space
77c8cf41 356considerations, is the Unihan database.
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357
358=item *
359
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360The properties \p{Blank} and \p{SpacePerl} have been added. "Blank" is like
361C isblank(), that is, it contains only "horizontal whitespace" (the space
362character is, the newline isn't), and the "SpacePerl" is the Unicode
363equivalent of C<\s> (\p{Space} isn't, since that includes the vertical
364tabulator character, whereas C<\s> doesn't.)
365
366See "New Unicode Properties" earlier in this document for additional
367information on changes with Unicode properties.
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368
369=back
370
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371=head2 Understanding of Numbers
372
373In general a lot of fixing has happened in the area of Perl's
374understanding of numbers, both integer and floating point. Since in
375many systems the standard number parsing functions like C<strtoul()>
376and C<atof()> seem to have bugs, Perl tries to work around their
377deficiencies. This results hopefully in more accurate numbers.
f39f21d8 378
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379Perl now tries internally to use integer values in numeric conversions
380and basic arithmetics (+ - * /) if the arguments are integers, and
381tries also to keep the results stored internally as integers.
057b7f2b 382This change leads to often slightly faster and always less lossy
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383arithmetics. (Previously Perl always preferred floating point numbers
384in its math.)
385
58175c9b 386=head2 Miscellaneous Changes
e1f170bd 387
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388=over 4
389
390=item *
391
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392AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
393to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
394
395=item *
396
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397C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
398in multiple arguments.)
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399
400=item *
401
58175c9b 402The builtin dump() now gives an optional warning
66023b77 403C<dump() better written as CORE::dump()>,
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404meaning that by default C<dump(...)> is resolved as the builtin
405dump() which dumps core and aborts, not as (possibly) user-defined
406C<sub dump>. To call the latter, qualify the call as C<&dump(...)>.
407(The whole dump() feature is to considered deprecated, and possibly
408removed/changed in future releases.)
409
410=item *
411
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412chomp() and chop() are now overridable. Note, however, that their
413prototype (as given by C<prototype("CORE::chomp")> is undefined,
414because it cannot be expressed and therefore one cannot really write
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415replacements to override these builtins.
416
417=item *
418
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419END blocks are now run even if you exit/die in a BEGIN block.
420Internally, the execution of END blocks is now controlled by
421PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
422behaviour for Perl embedders. This will default in 5.10. See
423L<perlembed>.
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424
425=item *
426
e1f170bd 427Formats now support zero-padded decimal fields.
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428
429=item *
430
77c8cf41 431Lvalue subroutines can now return C<undef> in list context.
44da0e71 432However, the lvalue subroutine feature still remains experimental.
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433
434=item *
435
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436A lost warning "Can't declare ... dereference in my" has been
437restored (Perl had it earlier but it became lost in later releases.)
438
439=item *
440
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441A new special regular expression variable has been introduced:
442C<$^N>, which contains the most-recently closed group (submatch).
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443
444=item *
445
61947107 446C<no Module;> now works even if there is no "sub unimport" in the Module.
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447
448=item *
449
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450The numerical comparison operators return C<undef> if either operand
451is a NaN. Previously the behaviour was unspecified.
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452
453=item *
454
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455The following builtin functions are now overridable: each(), keys(),
456pop(), push(), shift(), splice(), unshift().
457
458=item *
459
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460C<pack() / unpack()> now can group template letters with C<()> and then
461apply repetition/count modifiers on the groups.
462
463=item *
464
465C<pack() / unpack()> can now process the Perl internal numeric types:
466IVs, UVs, NVs-- and also long doubles, if supported by the platform.
79f69e33 467The template letters are C<j>, C<J>, C<F>, and C<D>.
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468
469=item *
470
61947107 471C<pack('U0a*', ...)> can now be used to force a string to UTF8.
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472
473=item *
474
61947107 475my __PACKAGE__ $obj now works.
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476
477=item *
478
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479The printf() and sprintf() now support parameter reordering using the
480C<%\d+\$> and C<*\d+\$> syntaxes. For example
481
482 print "%2\$s %1\$s\n", "foo", "bar";
483
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484will print "bar foo\n". This feature helps in writing
485internationalised software, and in general when the order
486of the parameters can vary.
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487
488=item *
489
e1f170bd 490prototype(\&) is now available.
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491
492=item *
493
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494prototype(\[$@%&]) is now available to implicitly create references
495(useful for example if you want to emulate the tie() interface).
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496
497=item *
498
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499A new command-line option, C<-t> is available. It is the
500little brother of C<-T>: instead of dieing on taint violations,
501lexical warnings are given. B<This is only meant as a temporary
502debugging aid while securing the code of old legacy applications.
503This is not a substitute for -T.>
504
505=item *
506
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507In other taint news, the C<exec LIST> and C<system LIST> have now been
508considered too risky (think C<exec @ARGV>: it can start any program
509with any arguments), and now the said forms cause a warning.
510You should carefully launder the arguments to guarantee their
511validity. In future releases of Perl the forms will become fatal
512errors so consider starting laundering now.
513
514=item *
515
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516If tr/// is just counting characters, it doesn't attempt to
517modify its target.
518
519=item *
520
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521untie() will now call an UNTIE() hook if it exists. See L<perltie>
522for details.
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523
524=item *
525
526L<utime> now supports C<utime undef, undef, @files> to change the
527file timestamps to the current time.
528
529=item *
530
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531The rules for allowing underscores (underbars) in numeric constants
532have been relaxed and simplified: now you can have an underscore
533simply B<between digits>.
f39f21d8 534
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535=item *
536
537Rather than relying on C's argv[0] (which may not contain a full pathname)
538where possible $^X is now set by asking the operating system.
539(eg by reading F</proc/self/exe> on Linux, F</proc/curproc/file> on FreeBSD)
540
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541=back
542
77c8cf41 543=head1 Modules and Pragmata
f39f21d8 544
1e13d81f 545=head2 New Modules and Pragmata
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546
547=over 4
548
549=item *
550
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551C<Attribute::Handlers> allows a class to define attribute handlers.
552
553 package MyPack;
554 use Attribute::Handlers;
555 sub Wolf :ATTR(SCALAR) { print "howl!\n" }
556
557 # later, in some package using or inheriting from MyPack...
558
559 my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
560
561Both variables and routines can have attribute handlers. Handlers can
562be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
563exact compilation phase (BEGIN, CHECK, INIT, or END).
564
565=item *
566
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567B<B::Concise> is a new compiler backend for walking the Perl syntax
568tree, printing concise info about ops, from Stephen McCamant. The
569output is highly customisable. See L<B::Concise>.
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570
571=item *
572
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573C<Class::ISA> for reporting the search path for a class's ISA tree,
574by Sean Burke, has been added. See L<Class::ISA>.
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575
576=item *
577
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578C<Cwd> has now a split personality: if possible, an XS extension is
579used, (this will hopefully be faster, more secure, and more robust)
580but if not possible, the familiar Perl implementation is used.
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581
582=item *
583
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584C<Devel::PPPort>, originally from Kenneth Albanowski and now
585maintained by Paul Marquess, has been added. It is primarily used
66023b77 586by C<h2xs> to enhance portability of XS modules between different
e1f170bd 587versions of Perl.
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588
589=item *
590
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591C<Digest>, frontend module for calculating digests (checksums), from
592Gisle Aas, has been added. See L<Digest>.
f39f21d8
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593
594=item *
595
61947107
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596C<Digest::MD5> for calculating MD5 digests (checksums) as defined in
597RFC 1321, from Gisle Aas, has been added. See L<Digest::MD5>.
f39f21d8
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598
599 use Digest::MD5 'md5_hex';
600
601 $digest = md5_hex("Thirsty Camel");
602
603 print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
604
61947107 605NOTE: the C<MD5> backward compatibility module is deliberately not
e1f170bd 606included since its further use is discouraged.
f39f21d8 607
f39f21d8
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608=item *
609
61947107 610C<Encode>, by Nick Ing-Simmons, provides a mechanism to translate
f39f21d8
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611between different character encodings. Support for Unicode,
612ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
613compiled in to the module. Several other encodings (like Japanese,
614Chinese, and MacIntosh encodings) are included and will be loaded at
61947107 615runtime. See L<Encode>.
f39f21d8
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616
617Any encoding supported by Encode module is also available to the
618":encoding()" layer if PerlIO is used.
619
61947107
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620=item *
621
622C<I18N::Langinfo> can be use to query locale information.
623See L<I18N::Langinfo>.
f39f21d8
JH
624
625=item *
626
61947107 627C<I18N::LangTags> has functions for dealing with RFC3066-style
bea4d472 628language tags, by Sean Burke. See L<I18N::LangTags>.
61947107
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629
630=item *
631
632C<ExtUtils::Constant> is a new tool for extension writers for
633generating XS code to import C header constants, by Nicholas Clark.
634See L<ExtUtils::Constant>.
635
636=item *
637
638C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
639from Damian Conway. See L<Filter::Simple>.
f39f21d8
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640
641 # in MyFilter.pm:
642
643 package MyFilter;
644
645 use Filter::Simple sub {
646 while (my ($from, $to) = splice @_, 0, 2) {
647 s/$from/$to/g;
648 }
649 };
650
651 1;
652
653 # in user's code:
654
655 use MyFilter qr/red/ => 'green';
656
657 print "red\n"; # this code is filtered, will print "green\n"
658 print "bored\n"; # this code is filtered, will print "bogreen\n"
659
660 no MyFilter;
661
662 print "red\n"; # this code is not filtered, will print "red\n"
663
61947107
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664=item *
665
666C<File::Temp> allows one to create temporary files and directories in
667an easy, portable, and secure way, by Tim Jenness. See L<File::Temp>.
668
669=item *
670
671C<Filter::Util::Call> provides you with the framework to write
672I<Source Filters> in Perl, from Paul Marquess. For most uses the
673frontend Filter::Simple is to be preferred. See L<Filter::Util::Call>.
674
675=item *
676
79f69e33
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677C<if> is a new pragma for conditional inclusion of modules, from
678Ilya Zakharevich.
679
680=item *
681
61947107
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682L<libnet> is a collection of perl5 modules related to network
683programming, from Graham Barr. See L<Net::FTP>, L<Net::NNTP>,
684L<Net::Ping>, L<Net::POP3>, L<Net::SMTP>, and L<Net::Time>.
685
686Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
f39f21d8
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687
688=item *
689
61947107 690C<List::Util> is a selection of general-utility list subroutines, like
bea4d472 691sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
f39f21d8
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692
693=item *
694
61947107
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695C<Locale::Constants>, C<Locale::Country>, C<Locale::Currency>, and
696C<Locale::Language>, from Neil Bowers, have been added. They provide the
697codes for various locale standards, such as "fr" for France, "usd" for
698US Dollar, and "jp" for Japanese.
f39f21d8
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699
700 use Locale::Country;
701
702 $country = code2country('jp'); # $country gets 'Japan'
703 $code = country2code('Norway'); # $code gets 'no'
704
705See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
61947107
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706and L<Locale::Language>.
707
708=item *
709
710C<Locale::Maketext> is localization framework from Sean Burke. See
711L<Locale::Maketext>, and L<Locale::Maketext::TPJ13>. The latter is an
712article about software localization, originally published in The Perl
713Journal #13, republished here with kind permission.
714
715=item *
716
717C<Memoize> can make your functions faster by trading space for time,
718from Mark-Jason Dominus. See L<Memoize>.
f39f21d8
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719
720=item *
721
61947107
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722C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
723as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
724Extensions)>.
f39f21d8
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725
726 use MIME::Base64;
727
728 $encoded = encode_base64('Aladdin:open sesame');
729 $decoded = decode_base64($encoded);
730
731 print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
732
61947107 733See L<MIME::Base64>.
f39f21d8
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734
735=item *
736
61947107
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737C<MIME::QuotedPrint> allows you to encode data in quoted-printable
738encoding, as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
739Extensions)>, from Gisle Aas.
f39f21d8
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740
741 use MIME::QuotedPrint;
742
743 $encoded = encode_qp("Smiley in Unicode: \x{263a}");
744 $decoded = decode_qp($encoded);
745
746 print $encoded, "\n"; # "Smiley in Unicode: =263A"
747
748MIME::QuotedPrint has been enhanced to provide the basic methods
749necessary to use it with PerlIO::Via as in :
750
751 use MIME::QuotedPrint;
057b7f2b 752 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8 753
61947107 754See L<MIME::QuotedPrint>.
f39f21d8
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755
756=item *
757
61947107
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758C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
759See L<NEXT>.
f39f21d8
JH
760
761=item *
762
1e13d81f
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763C<open> is a new pragma for setting the default I/O disciplines
764for open().
765
766=item *
767
61947107
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768C<PerlIO::Scalar> provides the implementation of IO to "in memory"
769Perl scalars as discussed above, from Nick Ing-Simmons. It also
770serves as an example of a loadable PerlIO layer. Other future
771possibilities include PerlIO::Array and PerlIO::Code.
772See L<PerlIO::Scalar>.
773
774=item *
775
776C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
777functionality provided by a class (typically implemented in perl
778code), from Nick Ing-Simmons.
f39f21d8
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779
780 use MIME::QuotedPrint;
057b7f2b 781 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8
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782
783This will automatically convert everything output to C<$fh>
61947107 784to Quoted-Printable. See L<PerlIO::Via>.
f39f21d8
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785
786=item *
787
1e13d81f 788C<Pod::ParseLink>, by Russ Allbery, has been added,
95f0a2f1 789to parse LZ<><> links in pods as described in the new
1e13d81f
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790perlpodspec.
791
792=item *
793
61947107 794C<Pod::Text::Overstrike>, by Joe Smith, has been added.
f39f21d8 795It converts POD data to formatted overstrike text.
61947107 796See L<Pod::Text::Overstrike>.
f39f21d8
JH
797
798=item *
799
61947107
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800C<Scalar::Util> is a selection of general-utility scalar subroutines,
801like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
802
803=item *
804
1e13d81f
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805C<sort> is a new pragma for controlling the behaviour of sort().
806
807=item *
808
61947107
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809C<Storable> gives persistence to Perl data structures by allowing the
810storage and retrieval of Perl data to and from files in a fast and
811compact binary format, from Raphael Manfredi. See L<Storable>.
812
813=item *
814
815C<Switch>, from Damian Conway, has been added. Just by saying
f39f21d8
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816
817 use Switch;
818
819you have C<switch> and C<case> available in Perl.
820
821 use Switch;
822
823 switch ($val) {
824
825 case 1 { print "number 1" }
826 case "a" { print "string a" }
827 case [1..10,42] { print "number in list" }
828 case (@array) { print "number in list" }
829 case /\w+/ { print "pattern" }
830 case qr/\w+/ { print "pattern" }
831 case (%hash) { print "entry in hash" }
832 case (\%hash) { print "entry in hash" }
833 case (\&sub) { print "arg to subroutine" }
834 else { print "previous case not true" }
835 }
836
61947107
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837See L<Switch>.
838
839=item *
840
841C<Test::More> is yet another framework for writing test scripts,
842more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
843
844=item *
845
aecce728 846C<Test::Simple> has basic utilities for writing tests, by Michael
61947107 847Schwern. See L<Test::Simple>.
77c8cf41
JH
848
849=item *
850
61947107
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851C<Text::Balanced> has been added, for extracting delimited text
852sequences from strings, from Damian Conway.
77c8cf41
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853
854 use Text::Balanced 'extract_delimited';
855
856 ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
857
858$a will be "'never say never'", $b will be ', he never said'.
859
860In addition to extract_delimited() there are also extract_bracketed(),
861extract_quotelike(), extract_codeblock(), extract_variable(),
862extract_tagged(), extract_multiple(), gen_delimited_pat(), and
863gen_extract_tagged(). With these you can implement rather advanced
61947107 864parsing algorithms. See L<Text::Balanced>.
77c8cf41
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865
866=item *
867
c2e23569 868C<threads> is an interface to interpreter threads, by Arthur Bergman.
61947107 869Interpreter threads (ithreads) is the new thread model introduced in
c2e23569
JH
870Perl 5.6 but only available as an internal interface for extension
871writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
77c8cf41
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872
873=item *
874
61947107
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875C<threads::shared> allows data sharing for interpreter threads, from
876Arthur Bergman. In the ithreads model any data sharing between
877threads must be explicit, as opposed to the old 5.005 thread model
878where data sharing was implicit. See L<threads::shared>.
77c8cf41
JH
879
880=item *
881
1f089b22
JH
882C<Tie::File>, by Mark-Jason Dominus, associates a Perl array with the
883lines of a file.
b3b08c80
JH
884
885=item *
886
79f69e33
JH
887C<Tie::Memoize>, by Ilya Zakharevich, provides on-demand loaded hashes.
888
889=item *
890
61947107 891C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
ba370e9b
JH
892references (unlike the standard Tie::RefHash) The module is contained
893within Tie::RefHash, see L<Tie::RefHash>.
77c8cf41
JH
894
895=item *
896
61947107
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897C<Time::HiRes> provides high resolution timing (ualarm, usleep,
898and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
77c8cf41
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899
900=item *
901
61947107
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902C<Unicode::UCD> offers a querying interface to the Unicode Character
903Database. See L<Unicode::UCD>.
77c8cf41
JH
904
905=item *
906
61947107
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907C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
908for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
77c8cf41
JH
909
910=item *
911
61947107
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912C<Unicode::Normalize> implements the various Unicode normalization
913forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
77c8cf41
JH
914
915=item *
916
61947107
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917C<XS::Typemap>, by Tim Jenness, is a test extension that exercises XS
918typemaps. Nothing gets installed but for extension writers the code
919is worth studying.
77c8cf41
JH
920
921=back
922
923=head2 Updated And Improved Modules and Pragmata
924
925=over 4
926
927=item *
928
61947107
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929The following independently supported modules have been updated to the
930newest versions from CPAN: CGI, CPAN, DB_File, File::Spec, File::Temp,
931Getopt::Long, Math::BigFloat, Math::BigInt, the podlators bundle
932(Pod::Man, Pod::Text), Pod::LaTeX, Pod::Parser, Storable,
933Term::ANSIColor, Test, Text-Tabs+Wrap.
77c8cf41
JH
934
935=item *
936
61947107 937The attributes::reftype() now works on tied arguments.
77c8cf41
JH
938
939=item *
940
057b7f2b 941AutoLoader can now be disabled with C<no AutoLoader;>.
77c8cf41
JH
942
943=item *
944
1e13d81f
JH
945B::Deparse has been significantly enhanced. It now can deparse almost
946all of the standard test suite (so that the tests still succeed).
947There is a make target "test.deparse" for trying this out.
77c8cf41
JH
948
949=item *
950
1e13d81f 951Class::Struct can now define the classes in compile time.
77c8cf41
JH
952
953=item *
954
1e13d81f
JH
955Class::Struct now assigns the array/hash element if the accessor
956is called with an array/hash element as the B<sole> argument.
77c8cf41
JH
957
958=item *
959
1e13d81f 960Data::Dumper has now an option to sort hashes.
77c8cf41
JH
961
962=item *
963
1e13d81f
JH
964Data::Dumper has now an option to dump code references
965using B::Deparse.
77c8cf41
JH
966
967=item *
968
44da0e71
JH
969DB_File now supports newer Berkeley DB versions, among
970other improvements.
971
972=item *
973
1e13d81f
JH
974The English module can now be used without the infamous performance
975hit by saying
77c8cf41 976
66023b77 977 use English '-no_match_vars';
77c8cf41 978
1e13d81f
JH
979(Assuming, of course, that one doesn't need the troublesome variables
980C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
981C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
77c8cf41
JH
982
983=item *
984
1e13d81f
JH
985Fcntl, Socket, and Sys::Syslog have been rewritten to use the
986new-style constant dispatch section (see L<ExtUtils::Constant>).
987This means that they will be more robust and hopefully faster.
77c8cf41
JH
988
989=item *
990
44da0e71
JH
991File::Find now chdir()s correctly when chasing symbolic links.
992
993=item *
994
1e13d81f
JH
995File::Find now has pre- and post-processing callbacks. It also
996correctly changes directories when chasing symbolic links. Callbacks
997(naughtily) exiting with "next;" instead of "return;" now work.
61947107
JH
998
999=item *
1000
1e13d81f
JH
1001File::Find is now (again) reentrant. It also has been made
1002more portable.
77c8cf41 1003
61947107
JH
1004=item *
1005
1e13d81f
JH
1006File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
1007prototype mismatch with CORE::glob().
61947107
JH
1008
1009=item *
1010
1011File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
1012the returned list of filenames.
77c8cf41
JH
1013
1014=item *
1015
1016Devel::Peek now has an interface for the Perl memory statistics
1017(this works only if you are using perl's malloc, and if you have
1018compiled with debugging).
1019
1020=item *
1021
1e13d81f
JH
1022IPC::Open3 now allows the use of numeric file descriptors.
1023
1024=item *
1025
77c8cf41
JH
1026IO::Socket has now atmark() method, which returns true if the socket
1027is positioned at the out-of-band mark. The method is also exportable
1028as a sockatmark() function.
1029
1030=item *
1031
1032IO::Socket::INET has support for ReusePort option (if your platform
1033supports it). The Reuse option now has an alias, ReuseAddr. For clarity
1034you may want to prefer ReuseAddr.
1035
1036=item *
1037
61947107
JH
1038IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
1039that the operating system will make one up.)
77c8cf41
JH
1040
1041=item *
1042
1e13d81f
JH
1043use lib now works identically to @INC. Removing directories
1044with 'no lib' now works.
1045
1046=item *
1047
58175c9b
JH
1048ExtUtils::MakeMaker now uses File::Spec internally, which hopefully
1049leads into better portability.
1050
1051=item *
1052
1e13d81f
JH
1053Math::BigFloat and Math::BigInt have undergone a full rewrite.
1054They are now magnitudes faster, and they support various
61947107 1055bignum libraries such as GMP and PARI as their backends.
f39f21d8
JH
1056
1057=item *
1058
44da0e71
JH
1059Math::Complex handles inf, NaN etc., better.
1060
1061=item *
1062
58175c9b
JH
1063Net::Ping has been muchly enhanced. Multihoming is now supported.
1064There is now "external" protocol which uses Net::Ping::External module
1065which runs external ping(1) and parses the output. A version of
1066Net::Ping::External is available in CPAN.
f39f21d8 1067
77c8cf41 1068=item *
f39f21d8 1069
da6838c8 1070POSIX::sigaction() is now much more flexible and robust.
61947107
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1071You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
1072handlers, installing new handlers was not atomic.
f39f21d8
JH
1073
1074=item *
1075
da6838c8 1076In Safe the C<%INC> now localised in a Safe compartment so that
76663d67
JH
1077use/require work.
1078
1079=item *
1080
44da0e71
JH
1081In SDBM_File on dosish platforms, some keys went missing because of
1082lack of support for files with "holes". A workaround for the problem
1083has been added.
1084
1085=item *
1086
da6838c8 1087In Search::Dict one can now have a pre-processing hook for the
76663d67 1088lines being searched.
1e13d81f
JH
1089
1090=item *
1091
1092The Shell module now has an OO interface.
1093
1094=item *
1095
61947107 1096The Test module has been significantly enhanced.
f39f21d8
JH
1097
1098=item *
1099
da6838c8 1100The vars pragma now supports declaring fully qualified variables.
77c8cf41 1101(Something that C<our()> does not and will not support.)
f39f21d8 1102
888aee59
JH
1103=item *
1104
58175c9b 1105The C<utf8::> name space (as in the pragma) provides various
61947107
JH
1106Perl-callable functions to provide low level access to Perl's
1107internal Unicode representation. At the moment only length()
1108has been implemented.
888aee59 1109
f39f21d8
JH
1110=back
1111
77c8cf41 1112=head1 Utility Changes
f39f21d8
JH
1113
1114=over 4
1115
1116=item *
1117
61947107 1118Emacs perl mode (emacs/cperl-mode.el) has been updated to version
77c8cf41 11194.31.
f39f21d8
JH
1120
1121=item *
1122
61947107 1123F<emacs/e2ctags.pl> is now much faster.
f39f21d8
JH
1124
1125=item *
1126
1e13d81f
JH
1127C<h2ph> now supports C trigraphs.
1128
1129=item *
1130
1131C<h2xs> now produces a template README.
f39f21d8 1132
77c8cf41
JH
1133=item *
1134
1e13d81f
JH
1135C<h2xs> now uses C<Devel::PPort> for better portability between
1136different versions of Perl.
f39f21d8
JH
1137
1138=item *
1139
1e13d81f 1140C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
61947107
JH
1141newly created extensions that define constants. Since the new code is
1142more correct (if you have two constants where the first one is a
1143prefix of the second one, the first constant B<never> gets defined),
1144less lossy (it uses integers for integer constant, as opposed to the
1145old code that used floating point numbers even for integer constants),
1146and slightly faster, you might want to consider regenerating your
1147extension code (the new scheme makes regenerating easy).
1148L<h2xs> now also supports C trigraphs.
f39f21d8
JH
1149
1150=item *
1151
1e13d81f 1152C<libnetcfg> has been added to configure the libnet.
f39f21d8
JH
1153
1154=item *
1155
1e13d81f 1156C<perlbug> is now much more robust. It also sends the bug report to
61947107 1157perl.org, not perl.com.
f39f21d8
JH
1158
1159=item *
1160
1e13d81f 1161C<perlcc> has been rewritten and its user interface (that is,
61947107 1162command line) is much more like that of the UNIX C compiler, cc.
44da0e71 1163(The perlbc tools has been removed. Use C<perlcc -B> instead.)
f39f21d8
JH
1164
1165=item *
1166
aecce728
JH
1167C<perlivp> is a new Installation Verification Procedure utility
1168for running any time after installing Perl.
f39f21d8
JH
1169
1170=item *
1171
1e13d81f 1172C<pod2html> now allows specifying a cache directory.
f39f21d8
JH
1173
1174=item *
1175
1e13d81f
JH
1176C<s2p> has been completely rewritten in Perl. (It is in fact a full
1177implementation of sed in Perl: you can use the sed functionality by
1178using the C<psed> utility.)
61947107
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1179
1180=item *
1181
1e13d81f 1182C<xsubpp> now understands POD documentation embedded in the *.xs files.
f39f21d8
JH
1183
1184=item *
1185
1e13d81f 1186C<xsubpp> now supports OUT keyword.
f39f21d8
JH
1187
1188=back
1189
77c8cf41 1190=head1 New Documentation
f39f21d8
JH
1191
1192=over 4
1193
1194=item *
1195
77c8cf41
JH
1196perl56delta details the changes between the 5.005 release and the
11975.6.0 release.
f39f21d8
JH
1198
1199=item *
1200
61947107
JH
1201perlclib documents the internal replacements for standard C library
1202functions. (Interesting only for extension writers and Perl core
1203hackers.)
1204
1205=item *
1206
77c8cf41 1207perldebtut is a Perl debugging tutorial.
f39f21d8 1208
77c8cf41 1209=item *
f39f21d8 1210
77c8cf41 1211perlebcdic contains considerations for running Perl on EBCDIC platforms.
f39f21d8 1212
77c8cf41
JH
1213=item *
1214
888aee59
JH
1215perlintro is a gentle introduction to Perl.
1216
1217=item *
1218
61947107
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1219perliol documents the internals of PerlIO with layers.
1220
1221=item *
1222
888aee59
JH
1223perlmodstyle is a style guide for writing modules.
1224
1225=item *
1226
77c8cf41 1227perlnewmod tells about writing and submitting a new module.
f39f21d8
JH
1228
1229=item *
1230
34babc16
JH
1231perlpacktut is a pack() tutorial.
1232
1233=item *
1234
888aee59
JH
1235perlpod has been rewritten to be clearer and to record the best
1236practices gathered over the years.
1237
1238=item *
1239
057b7f2b 1240perlpodspec is a more formal specification of the pod format,
888aee59
JH
1241mainly of interest for writers of pod applications, not to
1242people writing in pod.
1243
1244=item *
1245
77c8cf41 1246perlretut is a regular expression tutorial.
f39f21d8
JH
1247
1248=item *
1249
77c8cf41
JH
1250perlrequick is a regular expressions quick-start guide.
1251Yes, much quicker than perlretut.
f39f21d8 1252
77c8cf41 1253=item *
f39f21d8 1254
61947107
JH
1255perltodo has been updated.
1256
1257=item *
1258
888aee59 1259perltootc has been renamed as perltooc (to not to conflict
61947107 1260with perltoot in filesystems restricted to "8.3" names)
888aee59
JH
1261
1262=item *
1263
58175c9b
JH
1264perluniintro is an introduction to using Unicode in Perl.
1265(perlunicode is more of a detailed reference and background
1266information)
888aee59
JH
1267
1268=item *
1269
77c8cf41
JH
1270perlutil explains the command line utilities packaged with the Perl
1271distribution.
1272
1273=back
f39f21d8 1274
61947107
JH
1275The following platform-specific documents are available before
1276the installation as README.I<platform>, and after the installation
1277as perlI<platform>:
f39f21d8 1278
61947107
JH
1279 perlaix perlamiga perlapollo perlbeos perlbs2000
1280 perlce perlcygwin perldgux perldos perlepoc perlhpux
1281 perlhurd perlmachten perlmacos perlmint perlmpeix
1282 perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
1283 perltru64 perluts perlvmesa perlvms perlvos perlwin32
77c8cf41
JH
1284
1285=over 4
1286
1287=item *
1288
61947107
JH
1289The documentation for the POSIX-BC platform is called "BS2000", to avoid
1290confusion with the Perl POSIX module.
77c8cf41
JH
1291
1292=item *
1293
61947107
JH
1294The documentation for the WinCE platform is called "CE", to avoid
1295confusion with the perlwin32 documentation on 8.3-restricted filesystems.
77c8cf41
JH
1296
1297=back
1298
1299=head1 Performance Enhancements
1300
1301=over 4
1302
1303=item *
1304
44da0e71
JH
1305map() could get pathologically slow when the result list it generates
1306is larger than the source list. The performance has been improved for
1307common scenarios.
77c8cf41
JH
1308
1309=item *
1310
e1f170bd
JH
1311sort() has been changed to use primarily mergesort internally as
1312opposed to the earlier quicksort. For very small lists this may
1313result in slightly slower sorting times, but in general the speedup
1314should be at least 20%. Additional bonuses are that the worst case
1315behaviour of sort() is now better (in computer science terms it now
1316runs in time O(N log N), as opposed to quicksort's Theta(N**2)
1317worst-case run time behaviour), and that sort() is now stable
1318(meaning that elements with identical keys will stay ordered as they
1319were before the sort). See the C<sort> pragma for information.
77c8cf41 1320
05e25c75
JH
1321The story in more detail: suppose you want to serve yourself a little
1322slice of Pi.
1323
1324 @digits = ( 3,1,4,1,5,9 );
1325
1326A numerical sort of the digits will yield (1,1,3,4,5,9), as expected.
1327Which C<1> comes first is hard to know, since one C<1> looks pretty
1328much like any other. You can regard this as totally trivial,
1329or somewhat profound. However, if you just want to sort the even
1330digits ahead of the odd ones, then what will
1331
1332 sort { ($a % 2) <=> ($b % 2) } @digits;
1333
1334yield? The only even digit, C<4>, will come first. But how about
1335the odd numbers, which all compare equal? With the quicksort algorithm
1336used to implement Perl 5.6 and earlier, the order of ties is left up
1337to the sort. So, as you add more and more digits of Pi, the order
1338in which the sorted even and odd digits appear will change.
1339and, for sufficiently large slices of Pi, the quicksort algorithm
1340in Perl 5.8 won't return the same results even if reinvoked with the
1341same input. The justification for this rests with quicksort's
1342worst case behavior. If you run
1343
1344 sort { $a <=> $b } ( 1 .. $N , 1 .. $N );
1345
1346(something you might approximate if you wanted to merge two sorted
1347arrays using sort), doubling $N doesn't just double the quicksort time,
1348it I<quadruples> it. Quicksort has a worst case run time that can
1349grow like N**2, so-called I<quadratic> behaviour, and it can happen
1350on patterns that may well arise in normal use. You won't notice this
1351for small arrays, but you I<will> notice it with larger arrays,
1352and you may not live long enough for the sort to complete on arrays
1353of a million elements. So the 5.8 quicksort scrambles large arrays
1354before sorting them, as a statistical defence against quadratic behaviour.
1355But that means if you sort the same large array twice, ties may be
1356broken in different ways.
1357
1358Because of the unpredictability of tie-breaking order, and the quadratic
1359worst-case behaviour, quicksort was I<almost> replaced completely with
1360a stable mergesort. I<Stable> means that ties are broken to preserve
1361the original order of appearance in the input array. So
1362
1363 sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
1364
1365will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers
1366appear in the output in the same order they appeared in the input.
1367Mergesort has worst case O(NlogN) behaviour, the best value
1368attainable. And, ironically, this mergesort does particularly
1369well where quicksort goes quadratic: mergesort sorts (1..$N, 1..$N)
1370in O(N) time. But quicksort was rescued at the last moment because
1371it is faster than mergesort on certain inputs and platforms.
1372For example, if you really I<don't> care about the order of even
1373and odd digits, quicksort will run in O(N) time; it's very good
1374at sorting many repetitions of a small number of distinct elements.
1375The quicksort divide and conquer strategy works well on platforms
1376with relatively small, very fast, caches. Eventually, the problem gets
1377whittled down to one that fits in the cache, from which point it
1378benefits from the increased memory speed.
1379
1380Quicksort was rescued by implementing a sort pragma to control aspects
1381of the sort. The B<stable> subpragma forces stable behaviour,
1382regardless of algorithm. The B<_quicksort> and B<_mergesort>
1383subpragmas are heavy-handed ways to select the underlying implementation.
1384The leading C<_> is a reminder that these subpragmas may not survive
1385beyond 5.8. More appropriate mechanisms for selecting the implementation
1386exist, but they wouldn't have arrived in time to save quicksort.
1387
77c8cf41
JH
1388=item *
1389
1390Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
1391(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
1392reasonably fast while producing a much better spread of values than
1393the old hashing algorithm (originally by Chris Torek, later tweaked by
1394Ilya Zakharevich). Hash values output from the algorithm on a hash of
1395all 3-char printable ASCII keys comes much closer to passing the
1396DIEHARD random number generation tests. According to perlbench, this
1397change has not affected the overall speed of Perl.
1398
1399=item *
1400
1401unshift() should now be noticeably faster.
1402
1403=back
1404
1405=head1 Installation and Configuration Improvements
1406
1407=head2 Generic Improvements
1408
1409=over 4
1410
1411=item *
1412
1413INSTALL now explains how you can configure Perl to use 64-bit
1414integers even on non-64-bit platforms.
1415
1416=item *
1417
1418Policy.sh policy change: if you are reusing a Policy.sh file
1419(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
1420Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
1421them will now be changed to the new prefix, /foo/bar. (Previously
1422only $prefix changed.) If you do not like this new behaviour,
1423specify prefix, siteprefix, and vendorprefix explicitly.
1424
1425=item *
1426
1427A new optional location for Perl libraries, otherlibdirs, is available.
1428It can be used for example for vendor add-ons without disturbing Perl's
1429own library directories.
1430
1431=item *
1432
1433In many platforms the vendor-supplied 'cc' is too stripped-down to
1434build Perl (basically, 'cc' doesn't do ANSI C). If this seems
1435to be the case and 'cc' does not seem to be the GNU C compiler
1436'gcc', an automatic attempt is made to find and use 'gcc' instead.
1437
1438=item *
1439
1440gcc needs to closely track the operating system release to avoid
1441build problems. If Configure finds that gcc was built for a different
1442operating system release than is running, it now gives a clearly visible
1443warning that there may be trouble ahead.
1444
1445=item *
1446
1447If binary compatibility with the 5.005 release is not wanted, Configure
1448no longer suggests including the 5.005 modules in @INC.
1449
1450=item *
1451
1452Configure C<-S> can now run non-interactively.
1453
1454=item *
1455
44da0e71
JH
1456Configure support for pdp11-style memory models has been removed due
1457to obsolescence.
1458
1459=item *
1460
77c8cf41 1461configure.gnu now works with options with whitespace in them.
f39f21d8 1462
77c8cf41 1463=item *
f39f21d8 1464
77c8cf41 1465installperl now outputs everything to STDERR.
f39f21d8 1466
77c8cf41
JH
1467=item *
1468
1469$Config{byteorder} is now computed dynamically (this is more robust
1470with "fat binaries" where an executable image contains binaries for
1471more than one binary platform.)
f39f21d8
JH
1472
1473=item *
1474
1475Because PerlIO is now the default on most platforms, "-perlio" doesn't
1476get appended to the $Config{archname} (also known as $^O) anymore.
1477Instead, if you explicitly choose not to use perlio (Configure command
1478line option -Uuseperlio), you will get "-stdio" appended.
1479
1480=item *
1481
1482Another change related to the architecture name is that "-64all"
1483(-Duse64bitall, or "maximally 64-bit") is appended only if your
1484pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
1485
1486=item *
1487
77c8cf41
JH
1488In AFS installations one can configure the root of the AFS to be
1489somewhere else than the default F</afs> by using the Configure
1490parameter C<-Dafsroot=/some/where/else>.
1491
1492=item *
1493
61947107
JH
1494APPLLIB_EXP, a less-know configuration-time definition, has been
1495documented. It can be used to prepend site-specific directories
1496to Perl's default search path (@INC), see INSTALL for information.
1497
1498=item *
1499
77c8cf41
JH
1500The version of Berkeley DB used when the Perl (and, presumably, the
1501DB_File extension) was built is now available as
1502C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
1503from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
1504DB_VERSION_PATCH_CFG> from C.
1505
1506=item *
1507
61947107
JH
1508Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
1509has been documented in INSTALL.
77c8cf41
JH
1510
1511=item *
1512
61947107
JH
1513If you have CPAN access (either network or a local copy such as a
1514CD-ROM) you can during specify extra modules to Configure to build and
1515install with Perl using the -Dextras=... option. See INSTALL for
1516more details.
f39f21d8 1517
61947107 1518=item *
f39f21d8 1519
61947107
JH
1520In addition to config.over a new override file, config.arch, is
1521available. That is supposed to be used by hints file writers for
1522architecture-wide changes (as opposed to config.over which is for
1523site-wide changes).
f39f21d8
JH
1524
1525=item *
1526
e1f170bd
JH
1527If your file system supports symbolic links you can build Perl outside
1528of the source directory by
1529
1530 mkdir /tmp/perl/build/directory
1531 cd /tmp/perl/build/directory
1532 sh /path/to/perl/source/Configure -Dmksymlinks ...
1533
1534This will create in /tmp/perl/build/directory a tree of symbolic links
1535pointing to files in /path/to/perl/source. The original files are left
1536unaffected. After Configure has finished you can just say
1537
1538 make all test
1539
1540and Perl will be built and tested, all in /tmp/perl/build/directory.
1541
1542=item *
1543
61947107
JH
1544For Perl developers several new make targets for profiling
1545and debugging have been added, see L<perlhack>.
1546
1547=over 8
f39f21d8
JH
1548
1549=item *
1550
61947107
JH
1551Use of the F<gprof> tool to profile Perl has been documented in
1552L<perlhack>. There is a make target called "perl.gprof" for
1553generating a gprofiled Perl executable.
f39f21d8
JH
1554
1555=item *
1556
61947107
JH
1557If you have GCC 3, there is a make target called "perl.gcov" for
1558creating a gcoved Perl executable for coverage analysis. See
1559L<perlhack>.
f39f21d8
JH
1560
1561=item *
1562
61947107
JH
1563If you are on IRIX or Tru64 platforms, new profiling/debugging options
1564have been added, see L<perlhack> for more information about pixie and
1565Third Degree.
1566
1567=back
f39f21d8
JH
1568
1569=item *
1570
61947107
JH
1571Guidelines of how to construct minimal Perl installations have
1572been added to INSTALL.
f39f21d8
JH
1573
1574=item *
1575
61947107
JH
1576The Thread extension is now not built at all under ithreads
1577(C<Configure -Duseithreads>) because it wouldn't work anyway (the
1578Thread extension requires being Configured with C<-Duse5005threads>).
f39f21d8 1579
61947107
JH
1580But note that the Thread.pm interface is now shared by both
1581thread models.
f39f21d8 1582
61947107 1583=back
f39f21d8 1584
61947107 1585=head2 New Or Improved Platforms
f39f21d8 1586
61947107
JH
1587For the list of platforms known to support Perl,
1588see L<perlport/"Supported Platforms">.
1589
1590=over 4
f39f21d8
JH
1591
1592=item *
1593
61947107 1594AIX dynamic loading should be now better supported.
f39f21d8 1595
f39f21d8
JH
1596=item *
1597
77c8cf41
JH
1598AIX should now work better with gcc, threads, and 64-bitness. Also the
1599long doubles support in AIX should be better now. See L<perlaix>.
f39f21d8
JH
1600
1601=item *
1602
61947107
JH
1603After a long pause, AmigaOS has been verified to be happy with Perl.
1604
1605=item *
1606
77c8cf41 1607AtheOS (http://www.atheos.cx/) is a new platform.
f39f21d8 1608
77c8cf41 1609=item *
f39f21d8 1610
58175c9b
JH
1611BeOS has been reclaimed.
1612
1613=item *
1614
77c8cf41 1615DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
f39f21d8
JH
1616
1617=item *
1618
77c8cf41 1619DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
f39f21d8
JH
1620
1621=item *
1622
61947107
JH
1623EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
1624have been regained. Many test suite tests still fail and the
1625co-existence of Unicode and EBCDIC isn't quite settled, but the
1626situation is much better than with Perl 5.6. See L<perlos390>,
1627L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
f39f21d8
JH
1628
1629=item *
1630
61947107
JH
1631Building perl with -Duseithreads or -Duse5005threads now works under
1632HP-UX 10.20 (previously it only worked under 10.30 or later). You will
1633need a thread library package installed. See README.hpux.
f39f21d8 1634
77c8cf41 1635=item *
f39f21d8 1636
61947107
JH
1637MacOS Classic (MacPerl has of course been available since
1638perl 5.004 but now the source code bases of standard Perl
1639and MacPerl have been synchronised)
f39f21d8 1640
77c8cf41 1641=item *
f39f21d8 1642
61947107
JH
1643MacOS X (or Darwin) should now be able to build Perl even on HFS+
1644filesystems. (The case-insensitivity confused the Perl build process.)
f39f21d8 1645
888aee59
JH
1646=item *
1647
61947107 1648NCR MP-RAS is now supported.
888aee59
JH
1649
1650=item *
1651
58175c9b
JH
1652All the NetBSD specific patches (except for the installation
1653specific ones) have been merged back to the main distribution.
1654
1655=item *
1656
61947107 1657NetWare from Novell is now supported. See L<perlnetware>.
888aee59
JH
1658
1659=item *
1660
61947107 1661NonStop-UX is now supported.
888aee59
JH
1662
1663=item *
1664
44da0e71
JH
1665NEC SUPER-UX is now supported.
1666
1667=item *
1668
58175c9b
JH
1669All the OpenBSD specific patches (except for the installation
1670specific ones) have been merged back to the main distribution.
1671
1672=item *
1673
1674Perl has been tested with the GNU pth userlevel thread package
1675( http://www.gnu.org/software/pth/pth.html ) . All but one thread
1676test worked, and that one failure was because of test results arriving
1677in unexpected order.
1678
1679=item *
1680
61947107 1681Amdahl UTS UNIX mainframe platform is now supported.
888aee59
JH
1682
1683=item *
1684
61947107
JH
1685WinCE is now supported. See L<perlce>.
1686
1687=item *
1688
1689z/OS (formerly known as OS/390, formerly known as MVS OE) has now
1690support for dynamic loading. This is not selected by default,
1691however, you must specify -Dusedl in the arguments of Configure.
888aee59 1692
f39f21d8
JH
1693=back
1694
1695=head1 Selected Bug Fixes
1696
e1f170bd
JH
1697Numerous memory leaks and uninitialized memory accesses have been
1698hunted down. Most importantly anonymous subs used to leak quite
1699a bit.
ba370e9b 1700
f39f21d8
JH
1701=over 4
1702
1703=item *
1704
e1f170bd 1705The autouse pragma didn't work for Multi::Part::Function::Names.
f39f21d8
JH
1706
1707=item *
1708
44da0e71
JH
1709caller() could cause core dumps in certain situations. Carp was sometimes
1710affected by this problem.
1711
1712=item *
1713
e1f170bd
JH
1714chop(@list) in list context returned the characters chopped in
1715reverse order. This has been reversed to be in the right order.
f39f21d8
JH
1716
1717=item *
1718
e1f170bd
JH
1719Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
1720when building the Perl binary. The only exception to this is SunOS 4.x,
1721which needs them.
f39f21d8
JH
1722
1723=item *
1724
e1f170bd
JH
1725The behaviour of non-decimal but numeric string constants such as
1726"0x23" was platform-dependent: in some platforms that was seen as 35,
1727in some as 0, in some as a floating point number (don't ask). This
1728was caused by Perl using the operating system libraries in a situation
1729where the result of the string to number conversion is undefined: now
1730Perl consistently handles such strings as zero in numeric contexts.
f39f21d8
JH
1731
1732=item *
1733
e1f170bd 1734The order of DESTROYs has been made more predictable.
f39f21d8
JH
1735
1736=item *
1737
e1f170bd
JH
1738Several debugger fixes: exit code now reflects the script exit code,
1739condition C<"0"> now treated correctly, the C<d> command now checks
44da0e71
JH
1740line number, the C<$.> no longer gets corrupted, all debugger output
1741now goes correctly to the socket if RemotePort is set.
1742
1743=item *
1744
1745Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
1746when statically building extensions into perl. This has been corrected.
f39f21d8
JH
1747
1748=item *
1749
e1f170bd 1750L<dprofpp> -R didn't work.
f39f21d8
JH
1751
1752=item *
1753
e1f170bd 1754C<*foo{FORMAT}> now works.
44da0e71
JH
1755=item *
1756
1757Infinity is now recognized as a number.
f39f21d8
JH
1758
1759=item *
1760
e1f170bd
JH
1761UNIVERSAL::isa no longer caches methods incorrectly. (This broke
1762the Tk extension with 5.6.0.)
f39f21d8
JH
1763
1764=item *
1765
e1f170bd
JH
1766Lexicals I: lexicals outside an eval "" weren't resolved
1767correctly inside a subroutine definition inside the eval "" if they
1768were not already referenced in the top level of the eval""ed code.
f39f21d8
JH
1769
1770=item *
1771
e1f170bd
JH
1772Lexicals II: lexicals leaked at file scope into subroutines that
1773were declared before the lexicals.
f39f21d8
JH
1774
1775=item *
1776
44da0e71
JH
1777Lexical warnings now propagating correctly between scopes
1778and into C<eval "...">.
1779
1780=item *
1781
1782C<use warnings qw(FATAL all)> did not work as intended. This has been
1783corrected.
1784
1785=item *
1786
1787warnings::enabled() now reports the state of $^W correctly if the caller
1788isn't using lexical warnings.
f39f21d8
JH
1789
1790=item *
1791
e1f170bd 1792Line renumbering with eval and C<#line> now works.
f39f21d8
JH
1793
1794=item *
1795
e1f170bd 1796Fixed numerous memory leaks, especially in eval "".
f39f21d8
JH
1797
1798=item *
1799
e1f170bd
JH
1800mkdir() now ignores trailing slashes in the directory name,
1801as mandated by POSIX.
f39f21d8
JH
1802
1803=item *
1804
e1f170bd
JH
1805Some versions of glibc have a broken modfl(). This affects builds
1806with C<-Duselongdouble>. This version of Perl detects this brokenness
1807and has a workaround for it. The glibc release 2.2.2 is known to have
1808fixed the modfl() bug.
f39f21d8
JH
1809
1810=item *
1811
e1f170bd
JH
1812Modulus of unsigned numbers now works (4063328477 % 65535 used to
1813return 27406, instead of 27047).
f39f21d8
JH
1814
1815=item *
1816
e1f170bd
JH
1817Some "not a number" warnings introduced in 5.6.0 eliminated to be
1818more compatible with 5.005. Infinity is now recognised as a number.
f39f21d8 1819
77c8cf41 1820=item *
f39f21d8 1821
44da0e71
JH
1822Numeric conversions did not recognize changes in the string value
1823properly in certain circumstances.
1824
1825=item *
1826
e1f170bd 1827Attributes (like :shared) didn't work with our().
f39f21d8
JH
1828
1829=item *
1830
e1f170bd 1831our() variables will not cause "will not stay shared" warnings.
f39f21d8
JH
1832
1833=item *
1834
44da0e71
JH
1835"our" variables of the same name declared in two sibling blocks
1836resulted in bogus warnings about "redeclaration" of the variables.
1837The problem has been corrected.
1838
1839=item *
1840
e1f170bd 1841pack "Z" now correctly terminates the string with "\0".
f39f21d8
JH
1842
1843=item *
1844
e1f170bd
JH
1845Fix password routines which in some shadow password platforms
1846(e.g. HP-UX) caused getpwent() to return every other entry.
f39f21d8 1847
77c8cf41 1848=item *
f39f21d8 1849
e1f170bd
JH
1850The PERL5OPT environment variable (for passing command line arguments
1851to Perl) didn't work for more than a single group of options.
f39f21d8 1852
77c8cf41 1853=item *
f39f21d8 1854
e1f170bd 1855PERL5OPT with embedded spaces didn't work.
f39f21d8 1856
77c8cf41 1857=item *
f39f21d8 1858
e1f170bd 1859printf() no longer resets the numeric locale to "C".
f39f21d8 1860
77c8cf41 1861=item *
f39f21d8 1862
44da0e71
JH
1863C<qw(a\\b)> now parses correctly as C<'a\\b'>.
1864
1865=item *
1866
1867pos() did not return the correct value within s///ge in earlier
1868versions. This is now handled correctly.
f39f21d8 1869
77c8cf41 1870=item *
f39f21d8 1871
e1f170bd
JH
1872Printing quads (64-bit integers) with printf/sprintf now works
1873without the q L ll prefixes (assuming you are on a quad-capable platform).
f39f21d8 1874
77c8cf41 1875=item *
f39f21d8 1876
e1f170bd 1877Regular expressions on references and overloaded scalars now work.
f39f21d8 1878
ba370e9b
JH
1879=item *
1880
e1f170bd
JH
1881Right-hand side magic (GMAGIC) could in many cases such as string
1882concatenation be invoked too many times.
ba370e9b
JH
1883
1884=item *
1885
e1f170bd 1886scalar() now forces scalar context even when used in void context.
ba370e9b
JH
1887
1888=item *
1889
e1f170bd 1890SOCKS support is now much more robust.
ba370e9b
JH
1891
1892=item *
1893
e1f170bd
JH
1894sort() arguments are now compiled in the right wantarray context
1895(they were accidentally using the context of the sort() itself).
44da0e71
JH
1896The comparison block is now run in scalar context, and the arguments
1897to be sorted are always provided list context.
ba370e9b
JH
1898
1899=item *
1900
e1f170bd 1901Changed the POSIX character class C<[[:space:]]> to include the (very
c2e23569
JH
1902rarely used) vertical tab character. Added a new POSIX-ish character
1903class C<[[:blank:]]> which stands for horizontal whitespace
1904(currently, the space and the tab).
ba370e9b
JH
1905
1906=item *
1907
1908The tainting behaviour of sprintf() has been rationalized. It does
1909not taint the result of floating point formats anymore, making the
1910behaviour consistent with that of string interpolation.
1911
1912=item *
1913
44da0e71
JH
1914Some cases of inconsistent taint propagation (such as within hash
1915values) have been fixed.
1916
1917=item *
1918
1919The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
1920of simple pattern matches. These are now handled better.
1921
1922=item *
1923
1924Regular expression debug output (whether through C<use re 'debug'>
1925or via C<-Dr>) now looks better.
1926
1927=item *
1928
1929Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
1930bug has been fixed.
1931
1932=item *
1933
1934Use of $& could trigger a core dump under some situations. This
1935is now avoided.
1936
1937=item *
1938
c2e23569
JH
1939The regular expression captured submatches ($1, $2, ...) are now
1940more consistently unset if the match fails, instead of leaving false
1941data lying around in them.
1942
1943=item *
1944
44da0e71
JH
1945readline() on files opened in "slurp" mode could return an extra "" at
1946the end in certain situations. This has been corrected.
1947
1948=item *
1949
1950Autovivification of symbolic references of special variables described
1951in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
1952again now.
1953
1954=item *
1955
da6838c8 1956Sys::Syslog ignored the C<LOG_AUTH> constant.
ba370e9b
JH
1957
1958=item *
1959
e1f170bd 1960All but the first argument of the IO syswrite() method are now optional.
ba370e9b
JH
1961
1962=item *
1963
e1f170bd
JH
1964$AUTOLOAD, sort(), lock(), and spawning subprocesses
1965in multiple threads simultaneously are now thread-safe.
ba370e9b
JH
1966
1967=item *
1968
e1f170bd 1969Tie::ARRAY SPLICE method was broken.
ba370e9b
JH
1970
1971=item *
1972
e1f170bd 1973Allow read-only string on left hand side of non-modifying tr///.
ba370e9b
JH
1974
1975=item *
1976
e1f170bd 1977Several Unicode fixes.
ba370e9b
JH
1978
1979=over 8
1980
1981=item *
1982
e1f170bd
JH
1983BOMs (byte order marks) in the beginning of Perl files
1984(scripts, modules) should now be transparently skipped.
1985UTF-16 (UCS-2) encoded Perl files should now be read correctly.
ba370e9b
JH
1986
1987=item *
1988
e1f170bd 1989The character tables have been updated to Unicode 3.1.1.
ba370e9b
JH
1990
1991=item *
1992
e1f170bd 1993Comparing with utf8 data does not magically upgrade non-utf8 data
58175c9b
JH
1994into utf8. (This was a problem for example if you were mixing data
1995from I/O and Unicode data: your output might have got magically encoded
1996as UTF-8.)
1997
1998=item *
1999
2000Generating illegal Unicode code points like U+FFFE, or the UTF-16
2001surrogates, now also generates an optional warning.
ba370e9b
JH
2002
2003=item *
2004
e1f170bd 2005C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
f39f21d8 2006
77c8cf41 2007=item *
f39f21d8 2008
e1f170bd
JH
2009Concatenation with the C<.> operator or via variable interpolation,
2010C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
2011substitution with C<s///>, single-quoted UTF8, should now work.
f39f21d8 2012
77c8cf41 2013=item *
f39f21d8 2014
e1f170bd
JH
2015The C<tr///> operator now works. Note that the C<tr///CU>
2016functionality has been removed (but see pack('U0', ...)).
f39f21d8 2017
77c8cf41 2018=item *
f39f21d8 2019
e1f170bd 2020C<eval "v200"> now works.
f39f21d8 2021
77c8cf41 2022=item *
f39f21d8 2023
44da0e71
JH
2024Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
2025This has been corrected.
2026
2027=item *
2028
e1f170bd 2029Zero entries were missing from the Unicode classes like C<IsDigit>.
f39f21d8 2030
e1f170bd 2031=back
f39f21d8 2032
44da0e71
JH
2033=item *
2034
2035Large unsigned numbers (those above 2**31) could sometimes lose their
2036unsignedness, causing bogus results in arithmetic operations.
2037
77c8cf41 2038=back
f39f21d8 2039
77c8cf41 2040=head2 Platform Specific Changes and Fixes
f39f21d8
JH
2041
2042=over 4
2043
2044=item *
2045
77c8cf41 2046BSDI 4.*
f39f21d8 2047
77c8cf41 2048Perl now works on post-4.0 BSD/OSes.
f39f21d8
JH
2049
2050=item *
2051
77c8cf41 2052All BSDs
f39f21d8 2053
057b7f2b 2054Setting C<$0> now works (as much as possible; see L<perlvar> for details).
f39f21d8
JH
2055
2056=item *
2057
77c8cf41 2058Cygwin
f39f21d8 2059
439f2f5c 2060Numerous updates; currently synchronised with Cygwin 1.3.10.
f39f21d8
JH
2061
2062=item *
2063
e1f170bd
JH
2064Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
2065
2066=item *
2067
77c8cf41 2068EPOC
f39f21d8 2069
77c8cf41 2070EPOC update after Perl 5.6.0. See README.epoc.
f39f21d8
JH
2071
2072=item *
2073
77c8cf41 2074FreeBSD 3.*
f39f21d8 2075
77c8cf41 2076Perl now works on post-3.0 FreeBSDs.
f39f21d8
JH
2077
2078=item *
2079
77c8cf41
JH
2080HP-UX
2081
439f2f5c 2082README.hpux updated; C<Configure -Duse64bitall> now works.
f39f21d8
JH
2083
2084=item *
2085
77c8cf41 2086IRIX
f39f21d8 2087
77c8cf41
JH
2088Numerous compilation flag and hint enhancements; accidental mixing
2089of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
f39f21d8 2090
77c8cf41 2091=item *
f39f21d8 2092
77c8cf41 2093Linux
f39f21d8 2094
e1f170bd
JH
2095=over 8
2096
2097=item *
2098
77c8cf41 2099Long doubles should now work (see INSTALL).
f39f21d8
JH
2100
2101=item *
2102
e1f170bd
JH
2103Linux previously had problems related to sockaddrlen when using
2104accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
2105
2106=back
2107
2108=item *
2109
77c8cf41 2110MacOS Classic
f39f21d8 2111
77c8cf41
JH
2112Compilation of the standard Perl distribution in MacOS Classic should
2113now work if you have the Metrowerks development environment and
2114the missing Mac-specific toolkit bits. Contact the macperl mailing
2115list for details.
f39f21d8
JH
2116
2117=item *
2118
77c8cf41 2119MPE/iX
f39f21d8 2120
77c8cf41 2121MPE/iX update after Perl 5.6.0. See README.mpeix.
f39f21d8
JH
2122
2123=item *
2124
77c8cf41 2125NetBSD/sparc
f39f21d8 2126
77c8cf41 2127Perl now works on NetBSD/sparc.
f39f21d8
JH
2128
2129=item *
2130
77c8cf41 2131OS/2
f39f21d8 2132
77c8cf41 2133Now works with usethreads (see INSTALL).
f39f21d8
JH
2134
2135=item *
2136
77c8cf41 2137Solaris
f39f21d8 2138
77c8cf41 213964-bitness using the Sun Workshop compiler now works.
f39f21d8
JH
2140
2141=item *
2142
77c8cf41 2143Tru64 (aka Digital UNIX, aka DEC OSF/1)
f39f21d8 2144
77c8cf41
JH
2145The operating system version letter now recorded in $Config{osvers}.
2146Allow compiling with gcc (previously explicitly forbidden). Compiling
2147with gcc still not recommended because buggy code results, even with
2148gcc 2.95.2.
f39f21d8
JH
2149
2150=item *
2151
77c8cf41
JH
2152Unicos
2153
2154Fixed various alignment problems that lead into core dumps either
2155during build or later; no longer dies on math errors at runtime;
2156now using full quad integers (64 bits), previously was using
2157only 46 bit integers for speed.
f39f21d8
JH
2158
2159=item *
2160
77c8cf41
JH
2161VMS
2162
2163chdir() now works better despite a CRT bug; now works with MULTIPLICITY
2164(see INSTALL); now works with Perl's malloc.
f39f21d8 2165
00bb525a
CB
2166The tainting of C<%ENV> elements via C<keys> or C<values> was previously
2167unimplemented. It now works as documented.
2168
2169The C<waitpid> emulation has been improved. The worst bug (now fixed)
2170was that a pid of -1 would cause a wildcard search of all processes on
2171the system. The most significant enhancement is that we can now
2172usually get the completion status of a terminated process.
2173
2174POSIX-style signals are now emulated much better on VMS versions prior
2175to 7.0.
2176
2177The C<system> function and backticks operator have improved
2178functionality and better error handling.
2179
161720b2
CB
2180File access tests now use current process privileges rather than the
2181user's default privileges, which could sometimes result in a mismatch
2182between reported access and actual access.
2183
f39f21d8
JH
2184=item *
2185
77c8cf41 2186Windows
f39f21d8 2187
77c8cf41 2188=over 8
f39f21d8
JH
2189
2190=item *
2191
77c8cf41 2192accept() no longer leaks memory.
f39f21d8
JH
2193
2194=item *
2195
e1f170bd
JH
2196Borland C++ v5.5 is now a supported compiler that can build Perl.
2197However, the generated binaries continue to be incompatible with those
2198generated by the other supported compilers (GCC and Visual C++).
2199
2200=item *
2201
77c8cf41 2202Better chdir() return value for a non-existent directory.
f39f21d8 2203
77c8cf41 2204=item *
f39f21d8 2205
e1f170bd
JH
2206Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
2207
2208=item *
2209
77c8cf41 2210New %ENV entries now propagate to subprocesses.
f39f21d8
JH
2211
2212=item *
2213
44da0e71
JH
2214Current directory entries in %ENV are now correctly propagated to child
2215processes.
2216
2217=item *
2218
77c8cf41
JH
2219$ENV{LIB} now used to search for libs under Visual C.
2220
2221=item *
2222
44da0e71
JH
2223fork() emulation has been improved in various ways, but still continues
2224to be experimental. See L<perlfork> for known bugs and caveats.
e1f170bd
JH
2225
2226=item *
2227
77c8cf41 2228A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
f39f21d8
JH
2229
2230=item *
2231
44da0e71
JH
2232Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
2233Other bugs in chdir() and Cwd::cwd() have also been fixed.
2234
2235=item *
2236
e1f170bd
JH
2237HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
2238
2239=item *
2240
2241The makefiles now provide a single switch to bulk-enable all the features
2242enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
2243
2244=item *
2245
77c8cf41 2246Allow REG_EXPAND_SZ keys in the registry.
f39f21d8
JH
2247
2248=item *
2249
77c8cf41 2250Can now send() from all threads, not just the first one.
f39f21d8
JH
2251
2252=item *
2253
77c8cf41 2254Fake signal handling reenabled, bugs and all.
f39f21d8
JH
2255
2256=item *
2257
44da0e71
JH
2258%SIG has been enabled under USE_ITHREADS, but its use is completely
2259unsupported under all configurations.
2260
2261=item *
2262
77c8cf41
JH
2263Less stack reserved per thread so that more threads can run
2264concurrently. (Still 16M per thread.)
f39f21d8
JH
2265
2266=item *
2267
c2e23569 2268C<File::Spec-&gt;tmpdir()> now prefers C:/temp over /tmp
77c8cf41 2269(works better when perl is running as service).
f39f21d8
JH
2270
2271=item *
2272
77c8cf41 2273Better UNC path handling under ithreads.
f39f21d8
JH
2274
2275=item *
2276
44da0e71
JH
2277wait(), waitpid() and backticks now return the correct exit status under
2278Windows 9x.
f39f21d8
JH
2279
2280=item *
2281
77c8cf41 2282winsock handle leak fixed.
f39f21d8
JH
2283
2284=back
2285
77c8cf41 2286=back
f39f21d8 2287
77c8cf41 2288=head1 New or Changed Diagnostics
f39f21d8 2289
ba370e9b
JH
2290=over 4
2291
2292=item *
2293
12bcd1a6
PM
2294The lexical warnings category "deprecated" is no longer a sub-category
2295of the "syntax" category. It is now a top-level category in its own
2296right.
2297
2298=item *
2299
77c8cf41
JH
2300All regular expression compilation error messages are now hopefully
2301easier to understand both because the error message now comes before
2302the failed regex and because the point of failure is now clearly
ba370e9b
JH
2303marked by a C<E<lt>-- HERE> marker.
2304
2305=item *
f39f21d8 2306
77c8cf41
JH
2307The various "opened only for", "on closed", "never opened" warnings
2308drop the C<main::> prefix for filehandles in the C<main> package,
bea4d472 2309for example C<STDIN> instead of C<main::STDIN>.
f39f21d8 2310
ba370e9b
JH
2311=item *
2312
77c8cf41
JH
2313The "Unrecognized escape" warning has been extended to include C<\8>,
2314C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
f39f21d8 2315
ba370e9b 2316=item *
f39f21d8 2317
77c8cf41
JH
2318Two new debugging options have been added: if you have compiled your
2319Perl with debugging, you can use the -DT and -DR options to trace
2320tokenising and to add reference counts to displaying variables,
2321respectively.
f39f21d8
JH
2322
2323=item *
2324
492652be
RF
2325perl5db.pl has been modified to present a more consistent commands
2326interface, via (CommandSet=580). perl5db.t was also added to test the
2327changes, and as a placeholder for further tests.
2328
2329See L<perldebug>
2330
2331=item *
2332
9000bd02
MJD
2333The debugger has a new C<dumpDepth> option to control the maximum
2334depth to which nested structures are dumped. The C<x> command has
2335been extended so that C<x N EXPR> dumps out the value of I<EXPR> to a
2336depth of at most I<N> levels.
2337
2338=item *
2339
77c8cf41
JH
2340If an attempt to use a (non-blessed) reference as an array index
2341is made, a warning is given.
f39f21d8
JH
2342
2343=item *
2344
77c8cf41
JH
2345C<push @a;> and C<unshift @a;> (with no values to push or unshift)
2346now give a warning. This may be a problem for generated and evaled
2347code.
f39f21d8 2348
ba370e9b
JH
2349=item *
2350
2351If you try to L<perlfunc/pack> a number less than 0 or larger than 255
2352using the C<"C"> format you will get an optional warning. Similarly
2353for the C<"c"> format and a number less than -128 or more than 127.
2354
2355=item *
2356
2357Certain regex modifiers such as C<(?o)> make sense only if applied to
2358the entire regex. You will an optional warning if you try to do otherwise.
2359
2360=item *
2361
c2e23569
JH
2362Using arrays or hashes as references (e.g. C<< %foo-&gt;{bar} >>
2363has been deprecated for a while. Now you will get an optional warning.
ba370e9b 2364
f39f21d8
JH
2365=back
2366
77c8cf41 2367=head1 Changed Internals
f39f21d8
JH
2368
2369=over 4
2370
2371=item *
2372
77c8cf41
JH
2373perlapi.pod (a companion to perlguts) now attempts to document the
2374internal API.
f39f21d8
JH
2375
2376=item *
2377
77c8cf41
JH
2378You can now build a really minimal perl called microperl.
2379Building microperl does not require even running Configure;
2380C<make -f Makefile.micro> should be enough. Beware: microperl makes
2381many assumptions, some of which may be too bold; the resulting
2382executable may crash or otherwise misbehave in wondrous ways.
2383For careful hackers only.
f39f21d8
JH
2384
2385=item *
2386
c2e23569
JH
2387Added rsignal(), whichsig(), do_join(), op_clear, op_null,
2388ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
2389interfaces to the publicised API. For the full list of the available
2390APIs see L<perlapi>.
f39f21d8
JH
2391
2392=item *
2393
77c8cf41 2394Made possible to propagate customised exceptions via croak()ing.
f39f21d8 2395
77c8cf41 2396=item *
f39f21d8 2397
95f0a2f1
SB
2398Now xsubs can have attributes just like subs. (Well, at least the
2399built-in attributes.)
f39f21d8
JH
2400
2401=item *
2402
77c8cf41
JH
2403dTHR and djSP have been obsoleted; the former removed (because it's
2404a no-op) and the latter replaced with dSP.
f39f21d8
JH
2405
2406=item *
2407
61947107
JH
2408PERL_OBJECT has been completely removed.
2409
2410=item *
2411
ba370e9b
JH
2412The MAGIC constants (e.g. C<'P'>) have been macrofied
2413(e.g. C<PERL_MAGIC_TIED>) for better source code readability
2414and maintainability.
2415
2416=item *
2417
2418The regex compiler now maintains a structure that identifies nodes in
2419the compiled bytecode with the corresponding syntactic features of the
2420original regex expression. The information is attached to the new
2421C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
2422complete information.
2423
2424=item *
2425
2426The C code has been made much more C<gcc -Wall> clean. Some warning
2427messages still remain in some platforms, so if you are compiling with
2428gcc you may see some warnings about dubious practices. The warnings
2429are being worked on.
2430
2431=item *
2432
2433F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
2434
2435=item *
2436
61947107
JH
2437Documentation on how to use the Perl source repository has been added
2438to F<Porting/repository.pod>.
f39f21d8 2439
888aee59
JH
2440=item *
2441
c2e23569 2442There are now several profiling make targets.
888aee59 2443
77c8cf41 2444=back
f39f21d8 2445
77c8cf41 2446=head1 Security Vulnerability Closed
f39f21d8 2447
77c8cf41 2448(This change was already made in 5.7.0 but bears repeating here.)
f39f21d8 2449
77c8cf41
JH
2450A potential security vulnerability in the optional suidperl component
2451of Perl was identified in August 2000. suidperl is neither built nor
2452installed by default. As of November 2001 the only known vulnerable
2453platform is Linux, most likely all Linux distributions. CERT and
2454various vendors and distributors have been alerted about the vulnerability.
2455See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
2456for more information.
f39f21d8 2457
77c8cf41
JH
2458The problem was caused by Perl trying to report a suspected security
2459exploit attempt using an external program, /bin/mail. On Linux
2460platforms the /bin/mail program had an undocumented feature which
2461when combined with suidperl gave access to a root shell, resulting in
2462a serious compromise instead of reporting the exploit attempt. If you
2463don't have /bin/mail, or if you have 'safe setuid scripts', or if
2464suidperl is not installed, you are safe.
f39f21d8 2465
77c8cf41
JH
2466The exploit attempt reporting feature has been completely removed from
2467Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
2468from all the Perl 5.7 releases), so that particular vulnerability
2469isn't there anymore. However, further security vulnerabilities are,
ba370e9b
JH
2470unfortunately, always possible. The suidperl functionality is most
2471probably going to be removed in Perl 5.10. In any case, suidperl
2472should only be used by security experts who know exactly what they are
2473doing and why they are using suidperl instead of some other solution
2474such as sudo (see http://www.courtesan.com/sudo/).
77c8cf41
JH
2475
2476=head1 New Tests
2477
76663d67
JH
2478Several new tests have been added, especially for the F<lib>
2479subsection. There are now about 34 000 individual tests (spread over
2480about 530 test scripts), in the regression suite (5.6.1 has about
248111700 tests, in 258 test scripts) Many of the new tests are introduced
2482by the new modules, but still in general Perl is now more thoroughly
2483tested.
2484
2485Because of the large number of tests, running the regression suite
2486will take considerably longer time than it used to: expect the suite
2487to take up to 4-5 times longer to run than in perl 5.6. In a really
2488fast machine you can hope to finish the suite in about 5 minutes
2489(wallclock time).
77c8cf41
JH
2490
2491The tests are now reported in a different order than in earlier Perls.
2492(This happens because the test scripts from under t/lib have been moved
2493to be closer to the library/extension they are testing.)
2494
f39f21d8
JH
2495=head1 Known Problems
2496
f39f21d8
JH
2497=head2 AIX
2498
2499=over 4
2500
2501=item *
2502
2503In AIX 4.2 Perl extensions that use C++ functions that use statics
2504may have problems in that the statics are not getting initialized.
2505In newer AIX releases this has been solved by linking Perl with
2506the libC_r library, but unfortunately in AIX 4.2 the said library
2507has an obscure bug where the various functions related to time
2508(such as time() and gettimeofday()) return broken values, and
2509therefore in AIX 4.2 Perl is not linked against the libC_r.
2510
2511=item *
2512
2513vac 5.0.0.0 May Produce Buggy Code For Perl
2514
2515The AIX C compiler vac version 5.0.0.0 may produce buggy code,
2516resulting in few random tests failing, but when the failing tests
2517are run by hand, they succeed. We suggest upgrading to at least
2518vac version 5.0.1.0, that has been known to compile Perl correctly.
439f2f5c 2519"lslpp -L|grep vac.C" will tell you the vac version. See README.aix.
f39f21d8
JH
2520
2521=back
2522
2523=head2 Amiga Perl Invoking Mystery
2524
2525One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
057b7f2b 2526works, but for example C<bin:perl -v> doesn't. The exact reason isn't
f39f21d8
JH
2527known but the current suspect is the F<ixemul> library.
2528
2529=head2 lib/ftmp-security tests warn 'system possibly insecure'
2530
2531Don't panic. Read INSTALL 'make test' section instead.
2532
fa09c185 2533=head2 FreeBSD 4.3, 4.4, 4.5 fail lib/File/Spec/t/rel2abs2rel.t
ef985a5e 2534
fa09c185
NC
2535F<lib/File/Spec/t/rel2abs2rel.t> tests that "`` works" by running a a perl 1
2536liner in backticks, using "$^X" as the path to perl. It is known to be
2537failing on FreeBSD 4.3, 4.4 and 4.5, but only when run as part of make test.
ef985a5e
NC
2538This seems to be a kernel problem rather than perl - reading the symlink
2539F</proc/curproc/file> returns "unknown" rather than the path to perl, and a
2540kernel debugger reveals that variable C<numfullpathfail2> in
fb6d9fa6 2541F</usr/src/sys/kern/vfs_cache.c> is being incremented whenever
ef985a5e 2542F</proc/curproc/file> fails to return the perl executable's path.
fa09c185
NC
2543[If you find that if fails on other versions of FreeBSD, please use perlbug
2544to report them to us. If you are able to fix the bug, even better.]
ef985a5e 2545
f39f21d8
JH
2546=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
2547
2548If perl is configured with -Duse64bitall, the successful result of the
2549subtest 10 of lib/posix may arrive before the successful result of the
2550subtest 9, which confuses the test harness so much that it thinks the
2551subtest 9 failed.
2552
2553=head2 Linux With Sfio Fails op/misc Test 48
2554
2555No known fix.
2556
a0aae13b
JH
2557=head2 Mac OS X
2558
2559The following tests are known to fail:
2560
2561 Failed Test Stat Wstat Total Fail Failed List of Failed
2562 -------------------------------------------------------------------------
2563 ../ext/DB_File/t/db-btree.t 0 11 ?? ?? % ??
2564 ../ext/DB_File/t/db-recno.t 149 3 2.01% 61 63 65
2565 ../ext/POSIX/t/posix.t 31 1 3.23% 10
a0aae13b 2566
f39f21d8
JH
2567=head2 OS/390
2568
2569OS/390 has rather many test failures but the situation is actually
2570better than it was in 5.6.0, it's just that so many new modules and
2571tests have been added.
2572
6123004a
JH
2573 ../ext/B/t/deparse.t 17 1 5.88% 14
2574 ../ext/IO/lib/IO/t/io_unix.t 5 4 80.00% 2-5
2575 ../lib/utf8.t 94 13 13.83% 27 30-31 43 46 73
2576 76 79 82 85 88 91
2577 94
2578 ../lib/Benchmark.t 1 256 159 1 0.63% 75
2579 ../lib/ExtUtils/t/Embed.t 9 9 100.00% 1-9
2580 ../lib/ExtUtils/t/ExtUtils.t 27 19 70.37% 5-23
2581 op/pat.t 858 9 1.05% 242-243 665 776 785
2582 832-834 845
2583 op/sprintf.t 224 3 1.34% 98 100 136
2584 op/tr.t 97 5 5.15% 63 71-74
2585 uni/fold.t 767 8 1.04% 25-26 62 169 196
2586 648 697-698
8ed7e7ad 258757 tests and 377 subtests skipped.
f39f21d8
JH
2588
2589=head2 op/sprintf tests 129 and 130
2590
2591The op/sprintf tests 129 and 130 are known to fail on some platforms.
2592Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
2593The failing platforms do not comply with the ANSI C Standard, line
259419ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
2595something other than "1" and "-1" when formatting 0.6 and -0.6 using
2596the printf format "%.0f", most often they produce "0" and "-0".)
2597
2598=head2 Failure of Thread tests
2599
fedd8cf1
JH
2600B<Note that support for 5.005-style threading remains experimental
2601and practically unsupported.>
f39f21d8
JH
2602
2603The following tests are known to fail due to fundamental problems in
2604the 5.005 threading implementation. These are not new failures--Perl
26055.005_0x has the same bugs, but didn't have these tests.
2606
6123004a
JH
2607 ../ext/List/Util/t/first.t 255 65280 7 4 57.14% 2 5-7
2608 ../lib/English.t 2 512 54 2 3.70% 2-3
2609 ../lib/Filter/Simple/t/data.t 6 3 50.00% 1-3
2610 ../lib/Filter/Simple/t/filter_onl 9 3 33.33% 1-2 5
2611 ../lib/autouse.t 10 1 10.00% 4
2612 op/flip.t 15 1 6.67% 15
fedd8cf1 2613
8ed7e7ad
JH
2614These failures are unlikely to get fixed as the 5.005-style
2615threads are considered fundamentally broken.
f39f21d8
JH
2616
2617=head2 UNICOS
2618
6123004a
JH
2619 ../ext/Socket/socketpair.t 1 256 45 1 2.22% 12
2620 ../lib/Math/Trig.t 26 1 3.85% 25
2621 ../lib/warnings.t 460 1 0.22% 425
2622 io/fs.t 36 1 2.78% 31
2623 op/numconvert.t 1440 13 0.90% 208 509-510
2624 657-658 665-666 829-830 989-990 1149-1150
f39f21d8 2625
0968fb3b 2626=head2 UNICOS and UNICOS/mk
0f71e040 2627
0968fb3b
JH
2628The io/fs test #31 is failing because in UNICOS and UNICOS/mk
2629truncate() cannot be used to grow the size of filehandles, only
2630to reduce the size. The workaround is to truncate files instead
2631of filehandles.
0f71e040 2632
f39f21d8
JH
2633=head2 UTS
2634
2635There are a few known test failures, see L<perluts>.
2636
2637=head2 VMS
2638
161720b2
CB
2639There should be no reported test failures with a default configuration,
2640though there are a number of tests marked TODO that point to areas
2641needing further debugging and/or porting work.
7207e29d 2642
f39f21d8
JH
2643=head2 Win32
2644
2645In multi-CPU boxes there are some problems with the I/O buffering:
8ed7e7ad
JH
2646some output may appear twice. The Win32 following failures are known
2647as of 5.7.3:
2648
024938dc
JH
2649 ..\ext/Encode/t/JP.t 4 1024 22 4 18.18% 9 14 18 21
2650 ..\ext/threads/t/end.t 6 4 66.67% 3-6
2651 ..\lib/blib.t 3 768 7 3 42.86% 1 4-5
f39f21d8
JH
2652
2653=head2 Localising a Tied Variable Leaks Memory
2654
2655 use Tie::Hash;
2656 tie my %tie_hash => 'Tie::StdHash';
2657
2658 ...
2659
2660 local($tie_hash{Foo}) = 1; # leaks
2661
2662Code like the above is known to leak memory every time the local()
2663is executed.
2664
aecce728
JH
2665=head2 Localising Tied Arrays and Hashes Is Broken
2666
2667 local %tied_array;
2668
2669doesn't work as one would expect: the old value is restored
2670incorrectly.
2671
f39f21d8
JH
2672=head2 Self-tying of Arrays and Hashes Is Forbidden
2673
2674Self-tying of arrays and hashes is broken in rather deep and
2675hard-to-fix ways. As a stop-gap measure to avoid people from getting
2676frustrated at the mysterious results (core dumps, most often) it is
2677for now forbidden (you will get a fatal error even from an attempt).
2678
f39f21d8
JH
2679=head2 Building Extensions Can Fail Because Of Largefiles
2680
2681Some extensions like mod_perl are known to have issues with
2682`largefiles', a change brought by Perl 5.6.0 in which file offsets
2683default to 64 bits wide, where supported. Modules may fail to compile
2684at all or compile and work incorrectly. Currently there is no good
2685solution for the problem, but Configure now provides appropriate
2686non-largefile ccflags, ldflags, libswanted, and libs in the %Config
2687hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
2688having problems can try configuring themselves without the
2689largefileness. This is admittedly not a clean solution, and the
2690solution may not even work at all. One potential failure is whether
2691one can (or, if one can, whether it's a good idea) link together at
2692all binaries with different ideas about file offsets, all this is
2693platform-dependent.
2694
aecce728
JH
2695=head2 Unicode Support on EBCDIC Still Spotty
2696
2697Though mostly working, Unicode support still has problem spots on
2698EBCDIC platforms. One such known spot are the C<\p{}> and C<\P{}>
2699regular expression constructs for code points less than 256: the
2700pP are testing for Unicode code points, not knowing about EBCDIC.
2701
f39f21d8
JH
2702=head2 The Compiler Suite Is Still Experimental
2703
44da0e71
JH
2704The compiler suite is slowly getting better but it continues to be
2705highly experimental. Use in production environments is discouraged.
f39f21d8 2706
c4f1ce08 2707=head2 The Long Double Support Is Still Experimental
f39f21d8
JH
2708
2709The ability to configure Perl's numbers to use "long doubles",
2710floating point numbers of hopefully better accuracy, is still
2711experimental. The implementations of long doubles are not yet
2712widespread and the existing implementations are not quite mature
2713or standardised, therefore trying to support them is a rare
2714and moving target. The gain of more precision may also be offset
2715by slowdown in computations (more bits to move around, and the
2716operations are more likely to be executed by less optimised
2717libraries).
33a87e58 2718
c4f1ce08
JH
2719=head2 Seen In Perl 5.7 But Gone Now
2720
c4f1ce08
JH
2721C<Time::Piece> (previously known as C<Time::Object>) was removed
2722because it was felt that it didn't have enough value in it to be a
2723core module. It is still a useful module, though, and is available
2724from the CPAN.
2725
cc0fca54
GS
2726=head1 Reporting Bugs
2727
d4ad863d
JH
2728If you find what you think is a bug, you might check the articles
2729recently posted to the comp.lang.perl.misc newsgroup and the perl
2730bug database at http://bugs.perl.org. There may also be
06a5f41f 2731information at http://www.perl.com/, the Perl Home Page.
cc0fca54
GS
2732
2733If you believe you have an unreported bug, please run the B<perlbug>
2734program included with your release. Be sure to trim your bug down
2735to a tiny but sufficient test case. Your bug report, along with the
d4ad863d 2736output of C<perl -V>, will be sent off to perlbug@perl.org to be
cc0fca54
GS
2737analysed by the Perl porting team.
2738
2739=head1 SEE ALSO
2740
2741The F<Changes> file for exhaustive details on what changed.
2742
2743The F<INSTALL> file for how to build Perl.
2744
2745The F<README> file for general stuff.
2746
2747The F<Artistic> and F<Copying> files for copyright information.
2748
2749=head1 HISTORY
2750
d468ca04 2751Written by Jarkko Hietaniemi <F<jhi@iki.fi>>.
cc0fca54
GS
2752
2753=cut