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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 Binary Incompatibility
50
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51B<Perl 5.8 is not binary compatible with earlier releases of Perl.>
52
53B<You have to recompile your XS modules.>
54
55(Pure Perl modules should continue to work.)
56
57The major reason for the discontinity is the new IO architecture
365d6a78 58called PerlIO. PerlIO is the default configuration because
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59without it many new features of Perl 5.8 cannot be used. In other
60words: you just have to recompile your modules, sorry about that.
6cc60dfb 61
365d6a78 62In future releases of Perl, non-PerlIO aware XS modules may become
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63completely unsupported. This shouldn't be too difficult for module
64authors, however: PerlIO has been designed as a drop-in replacement
65(at the source code level) for the stdio interface.
66
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67Depending on your platform, there are also other reasons why
68we decided to break binary compatibility, please read on.
69
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70=head2 64-bit platforms and malloc
71
057b7f2b 72If your pointers are 64 bits wide, the Perl malloc is no longer being
c2e23569 73used because it does not work well with 8-byte pointers. Also,
61947107 74usually the system mallocs on such platforms are much better optimized
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75for such large memory models than the Perl malloc. Some memory-hungry
76Perl applications like the PDL don't work well with Perl's malloc.
77Finally, other applications than Perl (like modperl) tend to prefer
78the system malloc. Such platforms include Alpha and 64-bit HPPA,
79MIPS, PPC, and Sparc.
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80
81=head2 AIX Dynaloading
82
83The AIX dynaloading now uses in AIX releases 4.3 and newer the native
84dlopen interface of AIX instead of the old emulated interface. This
85change will probably break backward compatibility with compiled
86modules. The change was made to make Perl more compliant with other
87applications like modperl which are using the AIX native interface.
88
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89=head2 Attributes for C<my> variables now handled at run-time.
90
91The C<my EXPR : ATTRS> syntax now applies variable attributes at
92run-time. (Subroutine and C<our> variables still get attributes applied
93at compile-time.) See L<attributes> for additional details. In particular,
94however, this allows variable attributes to be useful for C<tie> interfaces,
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95which was a deficiency of earlier releases. Note that the new semantics
96doesn't work with the Attribute::Handlers module (as of version 0.76).
95f0a2f1 97
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98=head2 Socket Extension Dynamic in VMS
99
100The Socket extension is now dynamically loaded instead of being
101statically built in. This may or may not be a problem with ancient
102TCP/IP stacks of VMS: we do not know since we weren't able to test
103Perl in such configurations.
104
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105=head2 IEEE-format Floating Point Default on OpenVMS Alpha
106
107Perl now uses IEEE format (T_FLOAT) as the default internal floating
108point format on OpenVMS Alpha, potentially breaking binary compatibility
109with external libraries or existing data. G_FLOAT is still available as
110a configuration option. The default on VAX (D_FLOAT) has not changed.
111
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112=head2 New Unicode Properties
113
114Unicode I<scripts> are now supported. Scripts are similar to (and superior
115to) Unicode I<blocks>. The difference between scripts and blocks is that
116scripts are the glyphs used by a language or a group of languages, while
117the blocks are more artificial groupings of (mostly) 256 characters based
118on the Unicode numbering.
119
120In general, scripts are more inclusive, but not universally so. For
121example, while the script C<Latin> includes all the Latin characters and
122their various diacritic-adorned versions, it does not include the various
123punctuation or digits (since they are not solely C<Latin>).
124
125A number of other properties are now supported, including C<\p{L&}>,
126C<\p{Any}> C<\p{Assigned}>, C<\p{Unassigned}>, C<\p{Blank}> and
127C<\p{SpacePerl}> (along with their C<\P{...}> versions, of course).
128See L<perlunicode> for details, and more additions.
129
130The C<In> or C<Is> prefix to names used with the C<\p{...}> and C<\P{...}>
131are now almost always optional. The only exception is that a C<In> prefix
132is required to signify a Unicode block when a block name conflicts with a
133script name. For example, C<\p{Tibetan}> refers to the script, while
134C<\p{InTibetan}> refers to the block. When there is no name conflict, you
135can omit the C<In> from the block name (e.g. C<\p{BraillePatterns}>), but
136to be safe, it's probably best to always use the C<In>).
77c8cf41 137
c2e23569 138=head2 REF(...) Instead Of SCALAR(...)
77c8cf41 139
057b7f2b 140A reference to a reference now stringifies as "REF(0x81485ec)" instead
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141of "SCALAR(0x81485ec)" in order to be more consistent with the return
142value of ref().
77c8cf41 143
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144=head2 pack/unpack D/F recycled
145
66023b77 146The undocumented pack/unpack template letters D/F have been recycled
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147for better use: now they stand for long double (if supported by the
148platform) and NV (Perl internal floating point type). (They used
6123004a 149to be aliases for d/f, but you never knew that.)
79f69e33 150
c2e23569 151=head2 Deprecations
77c8cf41 152
61947107 153=over 4
77c8cf41 154
61947107 155=item *
f39f21d8 156
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157The semantics of bless(REF, REF) were unclear and until someone proves
158it to make some sense, it is forbidden.
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159
160=item *
161
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162The obsolete chat2 library that should never have been allowed
163to escape the laboratory has been decommissioned.
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164
165=item *
166
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167The builtin dump() function has probably outlived most of its
168usefulness. The core-dumping functionality will remain in future
169available as an explicit call to C<CORE::dump()>, but in future
170releases the behaviour of an unqualified C<dump()> call may change.
171
172=item *
173
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174The very dusty examples in the eg/ directory have been removed.
175Suggestions for new shiny examples welcome but the main issue is that
176the examples need to be documented, tested and (most importantly)
177maintained.
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178
179=item *
180
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181The (bogus) escape sequences \8 and \9 now give an optional warning
182("Unrecognized escape passed through"). There is no need to \-escape
183any C<\w> character.
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184
185=item *
186
c2e23569 187The list of filenames from glob() (or <...>) is now by default sorted
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188alphabetically to be csh-compliant (which is what happened before
189in most UNIX platforms). (bsd_glob() does still sort platform
c2e23569 190natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
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191
192=item *
193
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194Spurious syntax errors generated in certain situations, when glob()
195caused File::Glob to be loaded for the first time, have been fixed.
196
197=item *
198
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199Although "you shouldn't do that", it was possible to write code that
200depends on Perl's hashed key order (Data::Dumper does this). The new
201algorithm "One-at-a-Time" produces a different hashed key order.
202More details are in L</"Performance Enhancements">.
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203
204=item *
205
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206lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
207In future releases this may become a fatal error.
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208
209=item *
210
057b7f2b 211The C<package;> syntax (C<package> without an argument) has been
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212deprecated. Its semantics were never that clear and its
213implementation even less so. If you have used that feature to
214disallow all but fully qualified variables, C<use strict;> instead.
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215
216=item *
217
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218The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
219recognised but now cause fatal errors. The previous behaviour of
220ignoring them by default and warning if requested was unacceptable
221since it, in a way, falsely promised that the features could be used.
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222
223=item *
224
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225The current user-visible implementation of pseudo-hashes (the weird
226use of the first array element) is deprecated starting from Perl 5.8.0
227and will be removed in Perl 5.10.0, and the feature will be
228implemented differently. Not only is the current interface rather
229ugly, but the current implementation slows down normal array and hash
230use quite noticeably. The C<fields> pragma interface will remain
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231available. The I<restricted hashes> interface is expected to
232be the replacement interface (see L<Hash::Util>).
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233
234=item *
235
aecce728 236The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
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237
238=item *
239
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240After years of trying the suidperl is considered to be too complex to
241ever be considered truly secure. The suidperl functionality is likely
242to be removed in a future release.
243
244=item *
245
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246The 5.005 threads model (module C<Thread>) is deprecated and expected
247to be removed in Perl 5.10. Multithreaded code should be migrated to
248the new ithreads model (see L<threads> and L<threads::shared>).
249
250=item *
251
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252The long deprecated uppercase aliases for the string comparison
253operators (EQ, NE, LT, LE, GE, GT) have now been removed.
254
255=item *
256
257The tr///C and tr///U features have been removed and will not return;
258the interface was a mistake. Sorry about that. For similar
259functionality, see pack('U0', ...) and pack('C0', ...).
f39f21d8 260
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261=item *
262
263Earlier Perls treated "sub foo (@bar)" as equivalent to "sub foo (@)".
264The prototypes are now checked at compile-time for invalid characters.
265An optional warning is generated ("Illegal character in prototype...")
266but this may be upgraded to a fatal error in a future release.
267
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268=back
269
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270=head1 Core Enhancements
271
77c8cf41 272=head2 PerlIO is Now The Default
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273
274=over 4
275
276=item *
277
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278IO is now by default done via PerlIO rather than system's "stdio".
279PerlIO allows "layers" to be "pushed" onto a file handle to alter the
280handle's behaviour. Layers can be specified at open time via 3-arg
281form of open:
f39f21d8 282
77c8cf41 283 open($fh,'>:crlf :utf8', $path) || ...
f39f21d8 284
77c8cf41 285or on already opened handles via extended C<binmode>:
f39f21d8 286
77c8cf41 287 binmode($fh,':encoding(iso-8859-7)');
f39f21d8 288
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289The built-in layers are: unix (low level read/write), stdio (as in
290previous Perls), perlio (re-implementation of stdio buffering in a
291portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
292but available on any platform). A mmap layer may be available if
293platform supports it (mostly UNIXes).
f39f21d8 294
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295Layers to be applied by default may be specified via the 'open' pragma.
296
297See L</"Installation and Configuration Improvements"> for the effects
298of PerlIO on your architecture name.
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299
300=item *
301
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302File handles can be marked as accepting Perl's internal encoding of Unicode
303(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
f39f21d8 304
77c8cf41 305 open($fh,">:utf8","Uni.txt");
f39f21d8 306
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307Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
308for you since it's not UTF-8 what you will be getting but instead
309UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
310http://www.unicode.org/unicode/reports/tr16/ for more information.
311In future releases this naming may change.
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312
313=item *
314
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315File handles can translate character encodings from/to Perl's internal
316Unicode form on read/write via the ":encoding()" layer.
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317
318=item *
319
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320File handles can be opened to "in memory" files held in Perl scalars via:
321
322 open($fh,'>', \$variable) || ...
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323
324=item *
325
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326Anonymous temporary files are available without need to
327'use FileHandle' or other module via
f39f21d8 328
77c8cf41 329 open($fh,"+>", undef) || ...
f39f21d8 330
77c8cf41 331That is a literal undef, not an undefined value.
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332
333=item *
334
77c8cf41 335The list form of C<open> is now implemented for pipes (at least on UNIX):
f39f21d8 336
77c8cf41 337 open($fh,"-|", 'cat', '/etc/motd')
f39f21d8 338
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339creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
340the child process.
f39f21d8 341
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342=item *
343
344If your locale environment variables (LANGUAGE, LC_ALL, LC_CTYPE, LANG)
345contain the strings 'UTF-8' or 'UTF8' (case-insensitive matching),
346the default encoding of your STDIN, STDOUT, and STDERR, and of
347B<any subsequent file open>, is UTF-8.
348
e1f170bd 349=back
f39f21d8 350
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351=head2 Restricted Hashes
352
353A restricted hash is restricted to a certain set of keys, no keys
354outside the set can be added. Also individual keys can be restricted
355so that the key cannot be deleted and the value cannot be changed.
356No new syntax is involved: the Hash::Util module is the interface.
357
3e33716f 358=head2 Safe Signals
f39f21d8 359
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360Perl used to be fragile in that signals arriving at inopportune moments
361could corrupt Perl's internal state. Now Perl postpones handling of
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362signals until it's safe (between opcodes).
363
56e5bb57 364This change may have surprising side effects because signals no longer
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365interrupt Perl instantly. Perl will now first finish whatever it was
366doing, like finishing an internal operation (like sort()) or an
367external operation (like an I/O operation), and only then look at any
368arrived signals (and before starting the next operation). No more corrupt
369internal state since the current operation is always finished first,
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370but the signal may take more time to get heard. Note that breaking
371out from potentially blocking operations should still work, though.
f39f21d8 372
e1f170bd 373=head2 Unicode Overhaul
f39f21d8 374
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375Unicode in general should be now much more usable than in Perl 5.6.0
376(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
377regular expressions should work now, Unicode in tr/// should work now,
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378Unicode in I/O should work now. See L<perluniintro> for introduction
379and L<perlunicode> for details.
f39f21d8 380
e1f170bd 381=over 4
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382
383=item *
384
e1f170bd 385The Unicode Character Database coming with Perl has been upgraded
822ebcc8 386to Unicode 3.2.0. For more information, see http://www.unicode.org/ .
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387
388=item *
389
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390For developers interested in enhancing Perl's Unicode capabilities:
391almost all the UCD files are included with the Perl distribution in
58175c9b 392the F<lib/unicore subdirectory>. The most notable omission, for space
77c8cf41 393considerations, is the Unihan database.
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394
395=item *
396
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397The properties \p{Blank} and \p{SpacePerl} have been added. "Blank" is like
398C isblank(), that is, it contains only "horizontal whitespace" (the space
399character is, the newline isn't), and the "SpacePerl" is the Unicode
400equivalent of C<\s> (\p{Space} isn't, since that includes the vertical
401tabulator character, whereas C<\s> doesn't.)
402
403See "New Unicode Properties" earlier in this document for additional
404information on changes with Unicode properties.
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405
406=back
407
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408=head2 Understanding of Numbers
409
410In general a lot of fixing has happened in the area of Perl's
411understanding of numbers, both integer and floating point. Since in
412many systems the standard number parsing functions like C<strtoul()>
413and C<atof()> seem to have bugs, Perl tries to work around their
414deficiencies. This results hopefully in more accurate numbers.
f39f21d8 415
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416Perl now tries internally to use integer values in numeric conversions
417and basic arithmetics (+ - * /) if the arguments are integers, and
418tries also to keep the results stored internally as integers.
057b7f2b 419This change leads to often slightly faster and always less lossy
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420arithmetics. (Previously Perl always preferred floating point numbers
421in its math.)
422
58175c9b 423=head2 Miscellaneous Changes
e1f170bd 424
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425=over 4
426
427=item *
428
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429AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
430to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
431
432=item *
433
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434C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
435in multiple arguments.)
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436
437=item *
438
58175c9b 439The builtin dump() now gives an optional warning
66023b77 440C<dump() better written as CORE::dump()>,
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441meaning that by default C<dump(...)> is resolved as the builtin
442dump() which dumps core and aborts, not as (possibly) user-defined
443C<sub dump>. To call the latter, qualify the call as C<&dump(...)>.
444(The whole dump() feature is to considered deprecated, and possibly
445removed/changed in future releases.)
446
447=item *
448
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449chomp() and chop() are now overridable. Note, however, that their
450prototype (as given by C<prototype("CORE::chomp")> is undefined,
451because it cannot be expressed and therefore one cannot really write
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452replacements to override these builtins.
453
454=item *
455
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456END blocks are now run even if you exit/die in a BEGIN block.
457Internally, the execution of END blocks is now controlled by
458PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
459behaviour for Perl embedders. This will default in 5.10. See
460L<perlembed>.
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461
462=item *
463
e1f170bd 464Formats now support zero-padded decimal fields.
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465
466=item *
467
77c8cf41 468Lvalue subroutines can now return C<undef> in list context.
44da0e71 469However, the lvalue subroutine feature still remains experimental.
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470
471=item *
472
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473A lost warning "Can't declare ... dereference in my" has been
474restored (Perl had it earlier but it became lost in later releases.)
475
476=item *
477
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478A new special regular expression variable has been introduced:
479C<$^N>, which contains the most-recently closed group (submatch).
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480
481=item *
482
61947107 483C<no Module;> now works even if there is no "sub unimport" in the Module.
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484
485=item *
486
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487The numerical comparison operators return C<undef> if either operand
488is a NaN. Previously the behaviour was unspecified.
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489
490=item *
491
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492The following builtin functions are now overridable: each(), keys(),
493pop(), push(), shift(), splice(), unshift().
494
495=item *
496
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497C<pack() / unpack()> now can group template letters with C<()> and then
498apply repetition/count modifiers on the groups.
499
500=item *
501
502C<pack() / unpack()> can now process the Perl internal numeric types:
503IVs, UVs, NVs-- and also long doubles, if supported by the platform.
79f69e33 504The template letters are C<j>, C<J>, C<F>, and C<D>.
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505
506=item *
507
61947107 508C<pack('U0a*', ...)> can now be used to force a string to UTF8.
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509
510=item *
511
61947107 512my __PACKAGE__ $obj now works.
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513
514=item *
515
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516The printf() and sprintf() now support parameter reordering using the
517C<%\d+\$> and C<*\d+\$> syntaxes. For example
518
519 print "%2\$s %1\$s\n", "foo", "bar";
520
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521will print "bar foo\n". This feature helps in writing
522internationalised software, and in general when the order
523of the parameters can vary.
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524
525=item *
526
e1f170bd 527prototype(\&) is now available.
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528
529=item *
530
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531prototype(\[$@%&]) is now available to implicitly create references
532(useful for example if you want to emulate the tie() interface).
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533
534=item *
535
58175c9b 536A new command-line option, C<-t> is available. It is the
b0c3fc92 537little brother of C<-T>: instead of dying on taint violations,
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538lexical warnings are given. B<This is only meant as a temporary
539debugging aid while securing the code of old legacy applications.
540This is not a substitute for -T.>
541
542=item *
543
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544In other taint news, the C<exec LIST> and C<system LIST> have now been
545considered too risky (think C<exec @ARGV>: it can start any program
546with any arguments), and now the said forms cause a warning.
547You should carefully launder the arguments to guarantee their
548validity. In future releases of Perl the forms will become fatal
549errors so consider starting laundering now.
550
551=item *
552
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553Tied hash interfaces are now required to have the EXISTS and DELETE
554methods (either own or inherited).
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555
556=item *
557
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558If tr/// is just counting characters, it doesn't attempt to
559modify its target.
560
561=item *
562
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563untie() will now call an UNTIE() hook if it exists. See L<perltie>
564for details.
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565
566=item *
567
568L<utime> now supports C<utime undef, undef, @files> to change the
569file timestamps to the current time.
570
571=item *
572
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573The rules for allowing underscores (underbars) in numeric constants
574have been relaxed and simplified: now you can have an underscore
575simply B<between digits>.
f39f21d8 576
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577=item *
578
579Rather than relying on C's argv[0] (which may not contain a full pathname)
580where possible $^X is now set by asking the operating system.
581(eg by reading F</proc/self/exe> on Linux, F</proc/curproc/file> on FreeBSD)
582
608dbdb1
RGS
583=item *
584
585A new variable, C<${^TAINT}>, indicates whether taint mode is enabled.
586
587=item *
588
589You can now override the readline() builtin, and this overrides also
590the <FILEHANDLE> angle bracket operator.
591
592=item *
593
594The command-line options -s and -F are now recognized on the shebang
595(#!) line.
596
4ac733c9
MJD
597=item *
598
599Use of the C</c> match modifier without an accompanying C</g> modifier
600elicits a new warning: C<Use of /c modifier is meaningless without /g>.
f34840d8 601
64e578a2 602Use of C</c> in substitutions, even with C</g>, elicits
f34840d8
MJD
603C<Use of /c modifier is meaningless in s///>.
604
476a4411 605Use of C</g> with C<split> elicits C<Use of /g modifier is meaningless
f34840d8 606in split>.
4ac733c9 607
f39f21d8
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608=back
609
77c8cf41 610=head1 Modules and Pragmata
f39f21d8 611
1e13d81f 612=head2 New Modules and Pragmata
f39f21d8
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613
614=over 4
615
616=item *
617
0e9b9e0c
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618C<Attribute::Handlers> allows a class to define attribute handlers.
619
620 package MyPack;
621 use Attribute::Handlers;
622 sub Wolf :ATTR(SCALAR) { print "howl!\n" }
623
624 # later, in some package using or inheriting from MyPack...
625
626 my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
627
628Both variables and routines can have attribute handlers. Handlers can
629be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
630exact compilation phase (BEGIN, CHECK, INIT, or END).
631
632=item *
633
61947107
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634B<B::Concise> is a new compiler backend for walking the Perl syntax
635tree, printing concise info about ops, from Stephen McCamant. The
636output is highly customisable. See L<B::Concise>.
f39f21d8
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637
638=item *
639
381874f1
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640The new bignum, bigint, and bigrat pragmas implement transparent
641bignum support (using the Math::BigInt, Math::BigFloat, and
642Math::BigRat backends), by Tels.
643
644=item *
645
61947107
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646C<Class::ISA> for reporting the search path for a class's ISA tree,
647by Sean Burke, has been added. See L<Class::ISA>.
f39f21d8
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648
649=item *
650
61947107
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651C<Cwd> has now a split personality: if possible, an XS extension is
652used, (this will hopefully be faster, more secure, and more robust)
653but if not possible, the familiar Perl implementation is used.
f39f21d8
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654
655=item *
656
e1f170bd
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657C<Devel::PPPort>, originally from Kenneth Albanowski and now
658maintained by Paul Marquess, has been added. It is primarily used
66023b77 659by C<h2xs> to enhance portability of XS modules between different
e1f170bd 660versions of Perl.
1e13d81f
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661
662=item *
663
61947107
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664C<Digest>, frontend module for calculating digests (checksums), from
665Gisle Aas, has been added. See L<Digest>.
f39f21d8
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666
667=item *
668
61947107
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669C<Digest::MD5> for calculating MD5 digests (checksums) as defined in
670RFC 1321, from Gisle Aas, has been added. See L<Digest::MD5>.
f39f21d8
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671
672 use Digest::MD5 'md5_hex';
673
674 $digest = md5_hex("Thirsty Camel");
675
676 print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
677
61947107 678NOTE: the C<MD5> backward compatibility module is deliberately not
e1f170bd 679included since its further use is discouraged.
f39f21d8 680
f39f21d8
JH
681=item *
682
f14caa53
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683C<Encode>, orginally by Nick Ing-Simmons and now maintained by Dan
684Kogai, provides a mechanism to translate between different character
685encodings. Support for Unicode, ISO-8859-1, and ASCII are compiled in
686to the module. Several other encodings (like the rest of the
687ISO-8859, CP*/Win*, Mac, KOI8-R, three variants EBCDIC, Chinese,
688Japanese, and Korean encodings) are included and can be loaded at
689runtime. (For space considerations, the largest Chinese encodings
690have been separated into their own CPAN module, Encode::HanExtra,
691which Encode will use if available). See L<Encode>.
f39f21d8
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692
693Any encoding supported by Encode module is also available to the
694":encoding()" layer if PerlIO is used.
695
61947107
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696=item *
697
a6d3fe4f 698C<Hash::Util> is the interface to the new I<restricted hashes>
02e156f1 699feature. (Implemented by Jeffrey Friedl, Nick Ing-Simmons, and
a6d3fe4f
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700Michael Schwern.)
701
702=item *
703
61947107
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704C<I18N::Langinfo> can be use to query locale information.
705See L<I18N::Langinfo>.
f39f21d8
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706
707=item *
708
61947107 709C<I18N::LangTags> has functions for dealing with RFC3066-style
bea4d472 710language tags, by Sean Burke. See L<I18N::LangTags>.
61947107
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711
712=item *
713
714C<ExtUtils::Constant> is a new tool for extension writers for
715generating XS code to import C header constants, by Nicholas Clark.
716See L<ExtUtils::Constant>.
717
718=item *
719
720C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
721from Damian Conway. See L<Filter::Simple>.
f39f21d8
JH
722
723 # in MyFilter.pm:
724
725 package MyFilter;
726
727 use Filter::Simple sub {
728 while (my ($from, $to) = splice @_, 0, 2) {
729 s/$from/$to/g;
730 }
731 };
732
733 1;
734
735 # in user's code:
736
737 use MyFilter qr/red/ => 'green';
738
739 print "red\n"; # this code is filtered, will print "green\n"
740 print "bored\n"; # this code is filtered, will print "bogreen\n"
741
742 no MyFilter;
743
744 print "red\n"; # this code is not filtered, will print "red\n"
745
61947107
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746=item *
747
748C<File::Temp> allows one to create temporary files and directories in
749an easy, portable, and secure way, by Tim Jenness. See L<File::Temp>.
750
751=item *
752
753C<Filter::Util::Call> provides you with the framework to write
754I<Source Filters> in Perl, from Paul Marquess. For most uses the
755frontend Filter::Simple is to be preferred. See L<Filter::Util::Call>.
756
757=item *
758
79f69e33
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759C<if> is a new pragma for conditional inclusion of modules, from
760Ilya Zakharevich.
761
762=item *
763
61947107
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764L<libnet> is a collection of perl5 modules related to network
765programming, from Graham Barr. See L<Net::FTP>, L<Net::NNTP>,
b929be1d
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766L<Net::Ping> (not part of libnet, but related), L<Net::POP3>,
767L<Net::SMTP>, and L<Net::Time>.
61947107
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768
769Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
f39f21d8
JH
770
771=item *
772
61947107 773C<List::Util> is a selection of general-utility list subroutines, like
bea4d472 774sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
f39f21d8
JH
775
776=item *
777
f14caa53
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778C<Locale::Constants>, C<Locale::Country>, C<Locale::Currency>
779C<Locale::Language>, and L<Locale::Script>, from Neil Bowers, have
780been added. They provide the codes for various locale standards, such
9d81ddc1 781as "fr" for France, "usd" for US Dollar, and "ja" for Japanese.
f39f21d8
JH
782
783 use Locale::Country;
784
785 $country = code2country('jp'); # $country gets 'Japan'
786 $code = country2code('Norway'); # $code gets 'no'
787
788See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
61947107
JH
789and L<Locale::Language>.
790
791=item *
792
793C<Locale::Maketext> is localization framework from Sean Burke. See
794L<Locale::Maketext>, and L<Locale::Maketext::TPJ13>. The latter is an
795article about software localization, originally published in The Perl
796Journal #13, republished here with kind permission.
797
798=item *
799
f14caa53 800C<Math::BigRat> for big rational numbers, to accompany Math::BigInt and
381874f1
JH
801Math::BigFloat, from Tels.
802
803=item *
804
61947107
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805C<Memoize> can make your functions faster by trading space for time,
806from Mark-Jason Dominus. See L<Memoize>.
f39f21d8
JH
807
808=item *
809
61947107
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810C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
811as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
812Extensions)>.
f39f21d8
JH
813
814 use MIME::Base64;
815
816 $encoded = encode_base64('Aladdin:open sesame');
817 $decoded = decode_base64($encoded);
818
819 print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
820
61947107 821See L<MIME::Base64>.
f39f21d8
JH
822
823=item *
824
61947107
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825C<MIME::QuotedPrint> allows you to encode data in quoted-printable
826encoding, as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
827Extensions)>, from Gisle Aas.
f39f21d8
JH
828
829 use MIME::QuotedPrint;
830
831 $encoded = encode_qp("Smiley in Unicode: \x{263a}");
832 $decoded = decode_qp($encoded);
833
834 print $encoded, "\n"; # "Smiley in Unicode: =263A"
835
836MIME::QuotedPrint has been enhanced to provide the basic methods
837necessary to use it with PerlIO::Via as in :
838
839 use MIME::QuotedPrint;
057b7f2b 840 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8 841
61947107 842See L<MIME::QuotedPrint>.
f39f21d8
JH
843
844=item *
845
61947107
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846C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
847See L<NEXT>.
f39f21d8
JH
848
849=item *
850
1e13d81f
JH
851C<open> is a new pragma for setting the default I/O disciplines
852for open().
853
854=item *
855
61947107
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856C<PerlIO::Scalar> provides the implementation of IO to "in memory"
857Perl scalars as discussed above, from Nick Ing-Simmons. It also
858serves as an example of a loadable PerlIO layer. Other future
859possibilities include PerlIO::Array and PerlIO::Code.
860See L<PerlIO::Scalar>.
861
862=item *
863
864C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
865functionality provided by a class (typically implemented in perl
866code), from Nick Ing-Simmons.
f39f21d8
JH
867
868 use MIME::QuotedPrint;
057b7f2b 869 open($fh,">Via(MIME::QuotedPrint)",$path);
f39f21d8
JH
870
871This will automatically convert everything output to C<$fh>
61947107 872to Quoted-Printable. See L<PerlIO::Via>.
f39f21d8
JH
873
874=item *
875
1e13d81f 876C<Pod::ParseLink>, by Russ Allbery, has been added,
95f0a2f1 877to parse LZ<><> links in pods as described in the new
1e13d81f
JH
878perlpodspec.
879
880=item *
881
61947107 882C<Pod::Text::Overstrike>, by Joe Smith, has been added.
f39f21d8 883It converts POD data to formatted overstrike text.
61947107 884See L<Pod::Text::Overstrike>.
f39f21d8
JH
885
886=item *
887
61947107
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888C<Scalar::Util> is a selection of general-utility scalar subroutines,
889like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
890
891=item *
892
1e13d81f
JH
893C<sort> is a new pragma for controlling the behaviour of sort().
894
895=item *
896
61947107
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897C<Storable> gives persistence to Perl data structures by allowing the
898storage and retrieval of Perl data to and from files in a fast and
e27159c9
JH
899compact binary format. Because in effect Storable does serialisation
900of Perl data structues, with it you can also clone deep, hierarchical
901datastructures. Storable was created by Raphael Manfredi but it is
902now maintained by the Perl development team. Storable has been
903enhanced to understand the two new hash features, Unicode keys and
904restricted hashes. See L<Storable>.
61947107
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905
906=item *
907
908C<Switch>, from Damian Conway, has been added. Just by saying
f39f21d8
JH
909
910 use Switch;
911
912you have C<switch> and C<case> available in Perl.
913
914 use Switch;
915
916 switch ($val) {
917
918 case 1 { print "number 1" }
919 case "a" { print "string a" }
920 case [1..10,42] { print "number in list" }
921 case (@array) { print "number in list" }
922 case /\w+/ { print "pattern" }
923 case qr/\w+/ { print "pattern" }
924 case (%hash) { print "entry in hash" }
925 case (\%hash) { print "entry in hash" }
926 case (\&sub) { print "arg to subroutine" }
927 else { print "previous case not true" }
928 }
929
61947107
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930See L<Switch>.
931
932=item *
933
934C<Test::More> is yet another framework for writing test scripts,
935more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
936
937=item *
938
aecce728 939C<Test::Simple> has basic utilities for writing tests, by Michael
61947107 940Schwern. See L<Test::Simple>.
77c8cf41
JH
941
942=item *
943
61947107
JH
944C<Text::Balanced> has been added, for extracting delimited text
945sequences from strings, from Damian Conway.
77c8cf41
JH
946
947 use Text::Balanced 'extract_delimited';
948
949 ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
950
951$a will be "'never say never'", $b will be ', he never said'.
952
953In addition to extract_delimited() there are also extract_bracketed(),
954extract_quotelike(), extract_codeblock(), extract_variable(),
955extract_tagged(), extract_multiple(), gen_delimited_pat(), and
956gen_extract_tagged(). With these you can implement rather advanced
61947107 957parsing algorithms. See L<Text::Balanced>.
77c8cf41
JH
958
959=item *
960
c2e23569 961C<threads> is an interface to interpreter threads, by Arthur Bergman.
61947107 962Interpreter threads (ithreads) is the new thread model introduced in
c2e23569
JH
963Perl 5.6 but only available as an internal interface for extension
964writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
77c8cf41
JH
965
966=item *
967
61947107
JH
968C<threads::shared> allows data sharing for interpreter threads, from
969Arthur Bergman. In the ithreads model any data sharing between
970threads must be explicit, as opposed to the old 5.005 thread model
971where data sharing was implicit. See L<threads::shared>.
77c8cf41
JH
972
973=item *
974
1f089b22
JH
975C<Tie::File>, by Mark-Jason Dominus, associates a Perl array with the
976lines of a file.
b3b08c80
JH
977
978=item *
979
79f69e33
JH
980C<Tie::Memoize>, by Ilya Zakharevich, provides on-demand loaded hashes.
981
982=item *
983
61947107 984C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
ba370e9b
JH
985references (unlike the standard Tie::RefHash) The module is contained
986within Tie::RefHash, see L<Tie::RefHash>.
77c8cf41
JH
987
988=item *
989
61947107
JH
990C<Time::HiRes> provides high resolution timing (ualarm, usleep,
991and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
77c8cf41
JH
992
993=item *
994
61947107
JH
995C<Unicode::UCD> offers a querying interface to the Unicode Character
996Database. See L<Unicode::UCD>.
77c8cf41
JH
997
998=item *
999
61947107
JH
1000C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
1001for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
77c8cf41
JH
1002
1003=item *
1004
61947107
JH
1005C<Unicode::Normalize> implements the various Unicode normalization
1006forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
77c8cf41
JH
1007
1008=item *
1009
61947107
JH
1010C<XS::Typemap>, by Tim Jenness, is a test extension that exercises XS
1011typemaps. Nothing gets installed but for extension writers the code
1012is worth studying.
77c8cf41
JH
1013
1014=back
1015
1016=head2 Updated And Improved Modules and Pragmata
1017
1018=over 4
1019
1020=item *
1021
61947107
JH
1022The following independently supported modules have been updated to the
1023newest versions from CPAN: CGI, CPAN, DB_File, File::Spec, File::Temp,
1024Getopt::Long, Math::BigFloat, Math::BigInt, the podlators bundle
1025(Pod::Man, Pod::Text), Pod::LaTeX, Pod::Parser, Storable,
1026Term::ANSIColor, Test, Text-Tabs+Wrap.
77c8cf41
JH
1027
1028=item *
1029
61947107 1030The attributes::reftype() now works on tied arguments.
77c8cf41
JH
1031
1032=item *
1033
057b7f2b 1034AutoLoader can now be disabled with C<no AutoLoader;>.
77c8cf41
JH
1035
1036=item *
1037
1e13d81f
JH
1038B::Deparse has been significantly enhanced. It now can deparse almost
1039all of the standard test suite (so that the tests still succeed).
1040There is a make target "test.deparse" for trying this out.
77c8cf41
JH
1041
1042=item *
1043
1e13d81f 1044Class::Struct can now define the classes in compile time.
77c8cf41
JH
1045
1046=item *
1047
1e13d81f
JH
1048Class::Struct now assigns the array/hash element if the accessor
1049is called with an array/hash element as the B<sole> argument.
77c8cf41
JH
1050
1051=item *
1052
797ec949
RGS
1053The return value of Cwd::fastcwd() is now tainted.
1054
1055=item *
1056
1e13d81f 1057Data::Dumper has now an option to sort hashes.
77c8cf41
JH
1058
1059=item *
1060
1e13d81f
JH
1061Data::Dumper has now an option to dump code references
1062using B::Deparse.
77c8cf41
JH
1063
1064=item *
1065
44da0e71
JH
1066DB_File now supports newer Berkeley DB versions, among
1067other improvements.
1068
1069=item *
1070
797ec949
RGS
1071Devel::Peek now has an interface for the Perl memory statistics
1072(this works only if you are using perl's malloc, and if you have
1073compiled with debugging).
1074
1075=item *
1076
1e13d81f
JH
1077The English module can now be used without the infamous performance
1078hit by saying
77c8cf41 1079
66023b77 1080 use English '-no_match_vars';
77c8cf41 1081
1e13d81f
JH
1082(Assuming, of course, that one doesn't need the troublesome variables
1083C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
1084C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
77c8cf41
JH
1085
1086=item *
1087
797ec949
RGS
1088ExtUtils::MakeMaker now uses File::Spec internally, which hopefully
1089leads into better portability.
1090
1091=item *
1092
1e13d81f
JH
1093Fcntl, Socket, and Sys::Syslog have been rewritten to use the
1094new-style constant dispatch section (see L<ExtUtils::Constant>).
1095This means that they will be more robust and hopefully faster.
77c8cf41
JH
1096
1097=item *
1098
44da0e71
JH
1099File::Find now chdir()s correctly when chasing symbolic links.
1100
1101=item *
1102
1e13d81f
JH
1103File::Find now has pre- and post-processing callbacks. It also
1104correctly changes directories when chasing symbolic links. Callbacks
1105(naughtily) exiting with "next;" instead of "return;" now work.
61947107
JH
1106
1107=item *
1108
1e13d81f
JH
1109File::Find is now (again) reentrant. It also has been made
1110more portable.
77c8cf41 1111
61947107
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1112=item *
1113
608dbdb1
RGS
1114The warnings issued by File::Find now belong to their own category.
1115You can enable/disable them with C<use/no warnings 'File::Find';>.
1116
1117=item *
1118
1e13d81f
JH
1119File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
1120prototype mismatch with CORE::glob().
61947107
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1121
1122=item *
1123
1124File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
1125the returned list of filenames.
77c8cf41
JH
1126
1127=item *
1128
1e13d81f
JH
1129IPC::Open3 now allows the use of numeric file descriptors.
1130
1131=item *
1132
77c8cf41
JH
1133IO::Socket has now atmark() method, which returns true if the socket
1134is positioned at the out-of-band mark. The method is also exportable
1135as a sockatmark() function.
1136
1137=item *
1138
1139IO::Socket::INET has support for ReusePort option (if your platform
1140supports it). The Reuse option now has an alias, ReuseAddr. For clarity
1141you may want to prefer ReuseAddr.
1142
1143=item *
1144
61947107
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1145IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
1146that the operating system will make one up.)
77c8cf41
JH
1147
1148=item *
1149
1e13d81f
JH
1150use lib now works identically to @INC. Removing directories
1151with 'no lib' now works.
1152
1153=item *
1154
1155Math::BigFloat and Math::BigInt have undergone a full rewrite.
1156They are now magnitudes faster, and they support various
61947107 1157bignum libraries such as GMP and PARI as their backends.
f39f21d8
JH
1158
1159=item *
1160
44da0e71
JH
1161Math::Complex handles inf, NaN etc., better.
1162
1163=item *
1164
b929be1d
JH
1165Net::Ping has been muchly enhanced: multihoming is now supported,
1166Win32 functionality is better, there is now time measuring
1167functionality (optionally high-resolution using Time::HiRes),
1168and there is now "external" protocol which uses Net::Ping::External
1169module which runs your external ping utility and parses the output.
1170A version of Net::Ping::External is available in CPAN.
1171
1172Note that some of the Net::Ping tests are disabled when running
1173under the Perl distribution since one cannot assume one or more
1174of the following: enabled echo port at localhost, full Internet
1175connectivity, or sympathetic firewalls. You can set the environment
1176variable PERL_TEST_Net_Ping to "1" (one) before running the Perl test
1177suite to enable all the Net::Ping tests.
f39f21d8 1178
77c8cf41 1179=item *
f39f21d8 1180
da6838c8 1181POSIX::sigaction() is now much more flexible and robust.
61947107
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1182You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
1183handlers, installing new handlers was not atomic.
f39f21d8
JH
1184
1185=item *
1186
da6838c8 1187In Safe the C<%INC> now localised in a Safe compartment so that
76663d67
JH
1188use/require work.
1189
1190=item *
1191
44da0e71
JH
1192In SDBM_File on dosish platforms, some keys went missing because of
1193lack of support for files with "holes". A workaround for the problem
1194has been added.
1195
1196=item *
1197
da6838c8 1198In Search::Dict one can now have a pre-processing hook for the
76663d67 1199lines being searched.
1e13d81f
JH
1200
1201=item *
1202
1203The Shell module now has an OO interface.
1204
1205=item *
1206
903fdac2
JH
1207In Sys::Syslog there is now a failover mechanism that will go
1208through alternative connection mechanisms until the message
1209is successfully logged.
1210
1211=item *
1212
61947107 1213The Test module has been significantly enhanced.
f39f21d8
JH
1214
1215=item *
1216
1cfd00ad
SR
1217Time::Local::timelocal() does not handle fractional seconds anymore.
1218The rationale is that neither does localtime(), and timelocal() and
1219localtime() are supposed to be inverses of each other.
1220
1221=item *
1222
da6838c8 1223The vars pragma now supports declaring fully qualified variables.
77c8cf41 1224(Something that C<our()> does not and will not support.)
f39f21d8 1225
888aee59
JH
1226=item *
1227
58175c9b 1228The C<utf8::> name space (as in the pragma) provides various
61947107
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1229Perl-callable functions to provide low level access to Perl's
1230internal Unicode representation. At the moment only length()
1231has been implemented.
888aee59 1232
f39f21d8
JH
1233=back
1234
77c8cf41 1235=head1 Utility Changes
f39f21d8
JH
1236
1237=over 4
1238
1239=item *
1240
61947107 1241Emacs perl mode (emacs/cperl-mode.el) has been updated to version
77c8cf41 12424.31.
f39f21d8
JH
1243
1244=item *
1245
61947107 1246F<emacs/e2ctags.pl> is now much faster.
f39f21d8
JH
1247
1248=item *
1249
54ba6336
JH
1250C<enc2xs> is a tool for people adding their own encodings to the
1251Encode module.
1252
1253=item *
1254
1e13d81f
JH
1255C<h2ph> now supports C trigraphs.
1256
1257=item *
1258
1259C<h2xs> now produces a template README.
f39f21d8 1260
77c8cf41
JH
1261=item *
1262
1e13d81f
JH
1263C<h2xs> now uses C<Devel::PPort> for better portability between
1264different versions of Perl.
f39f21d8
JH
1265
1266=item *
1267
1e13d81f 1268C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
61947107
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1269newly created extensions that define constants. Since the new code is
1270more correct (if you have two constants where the first one is a
1271prefix of the second one, the first constant B<never> gets defined),
1272less lossy (it uses integers for integer constant, as opposed to the
1273old code that used floating point numbers even for integer constants),
1274and slightly faster, you might want to consider regenerating your
1275extension code (the new scheme makes regenerating easy).
1276L<h2xs> now also supports C trigraphs.
f39f21d8
JH
1277
1278=item *
1279
1e13d81f 1280C<libnetcfg> has been added to configure the libnet.
f39f21d8
JH
1281
1282=item *
1283
1e13d81f 1284C<perlbug> is now much more robust. It also sends the bug report to
61947107 1285perl.org, not perl.com.
f39f21d8
JH
1286
1287=item *
1288
1e13d81f 1289C<perlcc> has been rewritten and its user interface (that is,
61947107 1290command line) is much more like that of the UNIX C compiler, cc.
44da0e71 1291(The perlbc tools has been removed. Use C<perlcc -B> instead.)
f39f21d8
JH
1292
1293=item *
1294
aecce728
JH
1295C<perlivp> is a new Installation Verification Procedure utility
1296for running any time after installing Perl.
f39f21d8
JH
1297
1298=item *
1299
54ba6336
JH
1300C<piconv> is an implementation of the character conversion utility
1301C<iconv>, demonstrating the new Encode module.
1302
1303=item *
1304
1e13d81f 1305C<pod2html> now allows specifying a cache directory.
f39f21d8
JH
1306
1307=item *
1308
bbed45f6
JH
1309C<pod2html> now produces XHTML 1.0.
1310
1311=item *
1312
9b856ef5 1313C<pod2html> now understands POD written using different line endings
bbed45f6
JH
1314(PC-like CRLF versus UNIX-like LF versus MacClassic-like CR).
1315
1316=item *
1317
1e13d81f
JH
1318C<s2p> has been completely rewritten in Perl. (It is in fact a full
1319implementation of sed in Perl: you can use the sed functionality by
1320using the C<psed> utility.)
61947107
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1321
1322=item *
1323
1e13d81f 1324C<xsubpp> now understands POD documentation embedded in the *.xs files.
f39f21d8
JH
1325
1326=item *
1327
1e13d81f 1328C<xsubpp> now supports OUT keyword.
f39f21d8
JH
1329
1330=back
1331
77c8cf41 1332=head1 New Documentation
f39f21d8
JH
1333
1334=over 4
1335
1336=item *
1337
77c8cf41
JH
1338perl56delta details the changes between the 5.005 release and the
13395.6.0 release.
f39f21d8
JH
1340
1341=item *
1342
61947107
JH
1343perlclib documents the internal replacements for standard C library
1344functions. (Interesting only for extension writers and Perl core
1345hackers.)
1346
1347=item *
1348
77c8cf41 1349perldebtut is a Perl debugging tutorial.
f39f21d8 1350
77c8cf41 1351=item *
f39f21d8 1352
77c8cf41 1353perlebcdic contains considerations for running Perl on EBCDIC platforms.
f39f21d8 1354
77c8cf41
JH
1355=item *
1356
888aee59
JH
1357perlintro is a gentle introduction to Perl.
1358
1359=item *
1360
61947107
JH
1361perliol documents the internals of PerlIO with layers.
1362
1363=item *
1364
888aee59
JH
1365perlmodstyle is a style guide for writing modules.
1366
1367=item *
1368
77c8cf41 1369perlnewmod tells about writing and submitting a new module.
f39f21d8
JH
1370
1371=item *
1372
34babc16
JH
1373perlpacktut is a pack() tutorial.
1374
1375=item *
1376
888aee59
JH
1377perlpod has been rewritten to be clearer and to record the best
1378practices gathered over the years.
1379
1380=item *
1381
057b7f2b 1382perlpodspec is a more formal specification of the pod format,
888aee59
JH
1383mainly of interest for writers of pod applications, not to
1384people writing in pod.
1385
1386=item *
1387
77c8cf41 1388perlretut is a regular expression tutorial.
f39f21d8
JH
1389
1390=item *
1391
77c8cf41
JH
1392perlrequick is a regular expressions quick-start guide.
1393Yes, much quicker than perlretut.
f39f21d8 1394
77c8cf41 1395=item *
f39f21d8 1396
61947107
JH
1397perltodo has been updated.
1398
1399=item *
1400
888aee59 1401perltootc has been renamed as perltooc (to not to conflict
61947107 1402with perltoot in filesystems restricted to "8.3" names)
888aee59
JH
1403
1404=item *
1405
58175c9b
JH
1406perluniintro is an introduction to using Unicode in Perl.
1407(perlunicode is more of a detailed reference and background
1408information)
888aee59
JH
1409
1410=item *
1411
77c8cf41
JH
1412perlutil explains the command line utilities packaged with the Perl
1413distribution.
1414
1415=back
f39f21d8 1416
61947107
JH
1417The following platform-specific documents are available before
1418the installation as README.I<platform>, and after the installation
1419as perlI<platform>:
f39f21d8 1420
61947107
JH
1421 perlaix perlamiga perlapollo perlbeos perlbs2000
1422 perlce perlcygwin perldgux perldos perlepoc perlhpux
1423 perlhurd perlmachten perlmacos perlmint perlmpeix
1424 perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
1425 perltru64 perluts perlvmesa perlvms perlvos perlwin32
77c8cf41
JH
1426
1427=over 4
1428
1429=item *
1430
61947107
JH
1431The documentation for the POSIX-BC platform is called "BS2000", to avoid
1432confusion with the Perl POSIX module.
77c8cf41
JH
1433
1434=item *
1435
6cd7d6d6
JH
1436The documentation for the WinCE platform is called perlce (README.ce
1437in the source code kit), to avoid confusion with the perlwin32
1438documentation on 8.3-restricted filesystems.
77c8cf41
JH
1439
1440=back
1441
1442=head1 Performance Enhancements
1443
1444=over 4
1445
1446=item *
1447
44da0e71
JH
1448map() could get pathologically slow when the result list it generates
1449is larger than the source list. The performance has been improved for
1450common scenarios.
77c8cf41
JH
1451
1452=item *
1453
e1f170bd
JH
1454sort() has been changed to use primarily mergesort internally as
1455opposed to the earlier quicksort. For very small lists this may
1456result in slightly slower sorting times, but in general the speedup
1457should be at least 20%. Additional bonuses are that the worst case
1458behaviour of sort() is now better (in computer science terms it now
1459runs in time O(N log N), as opposed to quicksort's Theta(N**2)
1460worst-case run time behaviour), and that sort() is now stable
1461(meaning that elements with identical keys will stay ordered as they
1462were before the sort). See the C<sort> pragma for information.
77c8cf41 1463
05e25c75
JH
1464The story in more detail: suppose you want to serve yourself a little
1465slice of Pi.
1466
1467 @digits = ( 3,1,4,1,5,9 );
1468
1469A numerical sort of the digits will yield (1,1,3,4,5,9), as expected.
1470Which C<1> comes first is hard to know, since one C<1> looks pretty
1471much like any other. You can regard this as totally trivial,
1472or somewhat profound. However, if you just want to sort the even
1473digits ahead of the odd ones, then what will
1474
1475 sort { ($a % 2) <=> ($b % 2) } @digits;
1476
1477yield? The only even digit, C<4>, will come first. But how about
1478the odd numbers, which all compare equal? With the quicksort algorithm
1479used to implement Perl 5.6 and earlier, the order of ties is left up
1480to the sort. So, as you add more and more digits of Pi, the order
1481in which the sorted even and odd digits appear will change.
1482and, for sufficiently large slices of Pi, the quicksort algorithm
1483in Perl 5.8 won't return the same results even if reinvoked with the
1484same input. The justification for this rests with quicksort's
1485worst case behavior. If you run
1486
1487 sort { $a <=> $b } ( 1 .. $N , 1 .. $N );
1488
1489(something you might approximate if you wanted to merge two sorted
1490arrays using sort), doubling $N doesn't just double the quicksort time,
1491it I<quadruples> it. Quicksort has a worst case run time that can
1492grow like N**2, so-called I<quadratic> behaviour, and it can happen
1493on patterns that may well arise in normal use. You won't notice this
1494for small arrays, but you I<will> notice it with larger arrays,
1495and you may not live long enough for the sort to complete on arrays
1496of a million elements. So the 5.8 quicksort scrambles large arrays
1497before sorting them, as a statistical defence against quadratic behaviour.
1498But that means if you sort the same large array twice, ties may be
1499broken in different ways.
1500
1501Because of the unpredictability of tie-breaking order, and the quadratic
1502worst-case behaviour, quicksort was I<almost> replaced completely with
1503a stable mergesort. I<Stable> means that ties are broken to preserve
1504the original order of appearance in the input array. So
1505
1506 sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
1507
1508will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers
1509appear in the output in the same order they appeared in the input.
1510Mergesort has worst case O(NlogN) behaviour, the best value
1511attainable. And, ironically, this mergesort does particularly
1512well where quicksort goes quadratic: mergesort sorts (1..$N, 1..$N)
1513in O(N) time. But quicksort was rescued at the last moment because
1514it is faster than mergesort on certain inputs and platforms.
1515For example, if you really I<don't> care about the order of even
1516and odd digits, quicksort will run in O(N) time; it's very good
1517at sorting many repetitions of a small number of distinct elements.
1518The quicksort divide and conquer strategy works well on platforms
1519with relatively small, very fast, caches. Eventually, the problem gets
1520whittled down to one that fits in the cache, from which point it
1521benefits from the increased memory speed.
1522
1523Quicksort was rescued by implementing a sort pragma to control aspects
1524of the sort. The B<stable> subpragma forces stable behaviour,
1525regardless of algorithm. The B<_quicksort> and B<_mergesort>
1526subpragmas are heavy-handed ways to select the underlying implementation.
1527The leading C<_> is a reminder that these subpragmas may not survive
1528beyond 5.8. More appropriate mechanisms for selecting the implementation
1529exist, but they wouldn't have arrived in time to save quicksort.
1530
77c8cf41
JH
1531=item *
1532
1533Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
f224927c 1534( http://burtleburtle.net/bob/hash/doobs.html ). This algorithm is
77c8cf41
JH
1535reasonably fast while producing a much better spread of values than
1536the old hashing algorithm (originally by Chris Torek, later tweaked by
1537Ilya Zakharevich). Hash values output from the algorithm on a hash of
1538all 3-char printable ASCII keys comes much closer to passing the
1539DIEHARD random number generation tests. According to perlbench, this
1540change has not affected the overall speed of Perl.
1541
1542=item *
1543
1544unshift() should now be noticeably faster.
1545
1546=back
1547
1548=head1 Installation and Configuration Improvements
1549
1550=head2 Generic Improvements
1551
1552=over 4
1553
1554=item *
1555
1556INSTALL now explains how you can configure Perl to use 64-bit
1557integers even on non-64-bit platforms.
1558
1559=item *
1560
1561Policy.sh policy change: if you are reusing a Policy.sh file
1562(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
1563Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
1564them will now be changed to the new prefix, /foo/bar. (Previously
1565only $prefix changed.) If you do not like this new behaviour,
1566specify prefix, siteprefix, and vendorprefix explicitly.
1567
1568=item *
1569
1570A new optional location for Perl libraries, otherlibdirs, is available.
1571It can be used for example for vendor add-ons without disturbing Perl's
1572own library directories.
1573
1574=item *
1575
1576In many platforms the vendor-supplied 'cc' is too stripped-down to
1577build Perl (basically, 'cc' doesn't do ANSI C). If this seems
1578to be the case and 'cc' does not seem to be the GNU C compiler
1579'gcc', an automatic attempt is made to find and use 'gcc' instead.
1580
1581=item *
1582
1583gcc needs to closely track the operating system release to avoid
1584build problems. If Configure finds that gcc was built for a different
1585operating system release than is running, it now gives a clearly visible
1586warning that there may be trouble ahead.
1587
1588=item *
1589
11d33b1d
PG
1590Since Perl 5.8 is not binary-compatible with previous releases
1591of Perl, Configure no longer suggests including the 5.005
1592modules in @INC.
77c8cf41
JH
1593
1594=item *
1595
1596Configure C<-S> can now run non-interactively.
1597
1598=item *
1599
44da0e71
JH
1600Configure support for pdp11-style memory models has been removed due
1601to obsolescence.
1602
1603=item *
1604
77c8cf41 1605configure.gnu now works with options with whitespace in them.
f39f21d8 1606
77c8cf41 1607=item *
f39f21d8 1608
77c8cf41 1609installperl now outputs everything to STDERR.
f39f21d8 1610
77c8cf41
JH
1611=item *
1612
1613$Config{byteorder} is now computed dynamically (this is more robust
1614with "fat binaries" where an executable image contains binaries for
1615more than one binary platform.)
f39f21d8
JH
1616
1617=item *
1618
1619Because PerlIO is now the default on most platforms, "-perlio" doesn't
1620get appended to the $Config{archname} (also known as $^O) anymore.
1621Instead, if you explicitly choose not to use perlio (Configure command
1622line option -Uuseperlio), you will get "-stdio" appended.
1623
1624=item *
1625
1626Another change related to the architecture name is that "-64all"
1627(-Duse64bitall, or "maximally 64-bit") is appended only if your
1628pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
1629
1630=item *
1631
77c8cf41
JH
1632In AFS installations one can configure the root of the AFS to be
1633somewhere else than the default F</afs> by using the Configure
1634parameter C<-Dafsroot=/some/where/else>.
1635
1636=item *
1637
61947107
JH
1638APPLLIB_EXP, a less-know configuration-time definition, has been
1639documented. It can be used to prepend site-specific directories
1640to Perl's default search path (@INC), see INSTALL for information.
1641
1642=item *
1643
77c8cf41
JH
1644The version of Berkeley DB used when the Perl (and, presumably, the
1645DB_File extension) was built is now available as
1646C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
1647from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
1648DB_VERSION_PATCH_CFG> from C.
1649
1650=item *
1651
61947107
JH
1652Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
1653has been documented in INSTALL.
77c8cf41
JH
1654
1655=item *
1656
61947107
JH
1657If you have CPAN access (either network or a local copy such as a
1658CD-ROM) you can during specify extra modules to Configure to build and
1659install with Perl using the -Dextras=... option. See INSTALL for
1660more details.
f39f21d8 1661
61947107 1662=item *
f39f21d8 1663
61947107
JH
1664In addition to config.over a new override file, config.arch, is
1665available. That is supposed to be used by hints file writers for
1666architecture-wide changes (as opposed to config.over which is for
1667site-wide changes).
f39f21d8
JH
1668
1669=item *
1670
e1f170bd
JH
1671If your file system supports symbolic links you can build Perl outside
1672of the source directory by
1673
1674 mkdir /tmp/perl/build/directory
1675 cd /tmp/perl/build/directory
1676 sh /path/to/perl/source/Configure -Dmksymlinks ...
1677
1678This will create in /tmp/perl/build/directory a tree of symbolic links
1679pointing to files in /path/to/perl/source. The original files are left
1680unaffected. After Configure has finished you can just say
1681
1682 make all test
1683
1684and Perl will be built and tested, all in /tmp/perl/build/directory.
1685
1686=item *
1687
61947107
JH
1688For Perl developers several new make targets for profiling
1689and debugging have been added, see L<perlhack>.
1690
1691=over 8
f39f21d8
JH
1692
1693=item *
1694
61947107
JH
1695Use of the F<gprof> tool to profile Perl has been documented in
1696L<perlhack>. There is a make target called "perl.gprof" for
1697generating a gprofiled Perl executable.
f39f21d8
JH
1698
1699=item *
1700
61947107
JH
1701If you have GCC 3, there is a make target called "perl.gcov" for
1702creating a gcoved Perl executable for coverage analysis. See
1703L<perlhack>.
f39f21d8
JH
1704
1705=item *
1706
61947107
JH
1707If you are on IRIX or Tru64 platforms, new profiling/debugging options
1708have been added, see L<perlhack> for more information about pixie and
1709Third Degree.
1710
1711=back
f39f21d8
JH
1712
1713=item *
1714
61947107
JH
1715Guidelines of how to construct minimal Perl installations have
1716been added to INSTALL.
f39f21d8
JH
1717
1718=item *
1719
61947107
JH
1720The Thread extension is now not built at all under ithreads
1721(C<Configure -Duseithreads>) because it wouldn't work anyway (the
1722Thread extension requires being Configured with C<-Duse5005threads>).
f39f21d8 1723
61947107
JH
1724But note that the Thread.pm interface is now shared by both
1725thread models.
f39f21d8 1726
d1eb8299
YST
1727=item *
1728
1729The Gconvert macro ($Config{d_Gconvert}) used by perl for stringifying
1730floating-point numbers is now more picky about using sprintf %.*g
1731rules for the conversion. Some platforms that used to use gcvt may
1732now resort to the slower sprintf.
1733
11d33b1d
PG
1734=item *
1735
1736The obsolete method of making a special (e.g., debugging) flavor
1737of perl by saying
1738
1739 make LIBPERL=libperld.a
1740
1741has been removed. Use -DDEBUGGING instead.
1742
61947107 1743=back
f39f21d8 1744
61947107 1745=head2 New Or Improved Platforms
f39f21d8 1746
61947107
JH
1747For the list of platforms known to support Perl,
1748see L<perlport/"Supported Platforms">.
1749
1750=over 4
f39f21d8
JH
1751
1752=item *
1753
61947107 1754AIX dynamic loading should be now better supported.
f39f21d8 1755
f39f21d8
JH
1756=item *
1757
77c8cf41
JH
1758AIX should now work better with gcc, threads, and 64-bitness. Also the
1759long doubles support in AIX should be better now. See L<perlaix>.
f39f21d8
JH
1760
1761=item *
1762
f224927c 1763AtheOS ( http://www.atheos.cx/ ) is a new platform.
f39f21d8 1764
77c8cf41 1765=item *
f39f21d8 1766
58175c9b
JH
1767BeOS has been reclaimed.
1768
1769=item *
1770
77c8cf41 1771DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
f39f21d8
JH
1772
1773=item *
1774
77c8cf41 1775DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
f39f21d8
JH
1776
1777=item *
1778
61947107
JH
1779EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
1780have been regained. Many test suite tests still fail and the
1781co-existence of Unicode and EBCDIC isn't quite settled, but the
1782situation is much better than with Perl 5.6. See L<perlos390>,
1783L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
f39f21d8
JH
1784
1785=item *
1786
61947107
JH
1787Building perl with -Duseithreads or -Duse5005threads now works under
1788HP-UX 10.20 (previously it only worked under 10.30 or later). You will
1789need a thread library package installed. See README.hpux.
f39f21d8 1790
77c8cf41 1791=item *
f39f21d8 1792
61947107
JH
1793MacOS Classic (MacPerl has of course been available since
1794perl 5.004 but now the source code bases of standard Perl
1795and MacPerl have been synchronised)
f39f21d8 1796
77c8cf41 1797=item *
f39f21d8 1798
61947107
JH
1799MacOS X (or Darwin) should now be able to build Perl even on HFS+
1800filesystems. (The case-insensitivity confused the Perl build process.)
f39f21d8 1801
888aee59
JH
1802=item *
1803
61947107 1804NCR MP-RAS is now supported.
888aee59
JH
1805
1806=item *
1807
58175c9b
JH
1808All the NetBSD specific patches (except for the installation
1809specific ones) have been merged back to the main distribution.
1810
1811=item *
1812
61947107 1813NetWare from Novell is now supported. See L<perlnetware>.
888aee59
JH
1814
1815=item *
1816
61947107 1817NonStop-UX is now supported.
888aee59
JH
1818
1819=item *
1820
44da0e71
JH
1821NEC SUPER-UX is now supported.
1822
1823=item *
1824
58175c9b
JH
1825All the OpenBSD specific patches (except for the installation
1826specific ones) have been merged back to the main distribution.
1827
1828=item *
1829
1830Perl has been tested with the GNU pth userlevel thread package
1831( http://www.gnu.org/software/pth/pth.html ) . All but one thread
1832test worked, and that one failure was because of test results arriving
1833in unexpected order.
1834
1835=item *
1836
11d33b1d
PG
1837Stratus VOS is now supported using Perl's native build method
1838(Configure). This is the recommended method to build Perl on
1839VOS. The older methods, which build miniperl, are still
1840available. See L<perlvos>.
1841
1842=item *
1843
61947107 1844Amdahl UTS UNIX mainframe platform is now supported.
888aee59
JH
1845
1846=item *
1847
61947107
JH
1848WinCE is now supported. See L<perlce>.
1849
1850=item *
1851
1852z/OS (formerly known as OS/390, formerly known as MVS OE) has now
1853support for dynamic loading. This is not selected by default,
1854however, you must specify -Dusedl in the arguments of Configure.
888aee59 1855
f39f21d8
JH
1856=back
1857
1858=head1 Selected Bug Fixes
1859
e1f170bd
JH
1860Numerous memory leaks and uninitialized memory accesses have been
1861hunted down. Most importantly anonymous subs used to leak quite
1862a bit.
ba370e9b 1863
f39f21d8
JH
1864=over 4
1865
1866=item *
1867
e1f170bd 1868The autouse pragma didn't work for Multi::Part::Function::Names.
f39f21d8
JH
1869
1870=item *
1871
44da0e71
JH
1872caller() could cause core dumps in certain situations. Carp was sometimes
1873affected by this problem.
1874
1875=item *
1876
e1f170bd
JH
1877chop(@list) in list context returned the characters chopped in
1878reverse order. This has been reversed to be in the right order.
f39f21d8
JH
1879
1880=item *
1881
e1f170bd
JH
1882Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
1883when building the Perl binary. The only exception to this is SunOS 4.x,
1884which needs them.
f39f21d8
JH
1885
1886=item *
1887
e1f170bd
JH
1888The behaviour of non-decimal but numeric string constants such as
1889"0x23" was platform-dependent: in some platforms that was seen as 35,
1890in some as 0, in some as a floating point number (don't ask). This
1891was caused by Perl using the operating system libraries in a situation
1892where the result of the string to number conversion is undefined: now
1893Perl consistently handles such strings as zero in numeric contexts.
f39f21d8
JH
1894
1895=item *
1896
e1f170bd 1897The order of DESTROYs has been made more predictable.
f39f21d8
JH
1898
1899=item *
1900
e1f170bd
JH
1901Several debugger fixes: exit code now reflects the script exit code,
1902condition C<"0"> now treated correctly, the C<d> command now checks
44da0e71
JH
1903line number, the C<$.> no longer gets corrupted, all debugger output
1904now goes correctly to the socket if RemotePort is set.
1905
1906=item *
1907
1908Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
1909when statically building extensions into perl. This has been corrected.
f39f21d8
JH
1910
1911=item *
1912
e1f170bd 1913L<dprofpp> -R didn't work.
f39f21d8
JH
1914
1915=item *
1916
e1f170bd 1917C<*foo{FORMAT}> now works.
44da0e71
JH
1918=item *
1919
1920Infinity is now recognized as a number.
f39f21d8
JH
1921
1922=item *
1923
e1f170bd
JH
1924UNIVERSAL::isa no longer caches methods incorrectly. (This broke
1925the Tk extension with 5.6.0.)
f39f21d8
JH
1926
1927=item *
1928
e1f170bd
JH
1929Lexicals I: lexicals outside an eval "" weren't resolved
1930correctly inside a subroutine definition inside the eval "" if they
1931were not already referenced in the top level of the eval""ed code.
f39f21d8
JH
1932
1933=item *
1934
e1f170bd
JH
1935Lexicals II: lexicals leaked at file scope into subroutines that
1936were declared before the lexicals.
f39f21d8
JH
1937
1938=item *
1939
44da0e71
JH
1940Lexical warnings now propagating correctly between scopes
1941and into C<eval "...">.
1942
1943=item *
1944
1945C<use warnings qw(FATAL all)> did not work as intended. This has been
1946corrected.
1947
1948=item *
1949
1950warnings::enabled() now reports the state of $^W correctly if the caller
1951isn't using lexical warnings.
f39f21d8
JH
1952
1953=item *
1954
e1f170bd 1955Line renumbering with eval and C<#line> now works.
f39f21d8
JH
1956
1957=item *
1958
e1f170bd 1959Fixed numerous memory leaks, especially in eval "".
f39f21d8
JH
1960
1961=item *
1962
0b2c215a
JH
1963Localised tied variables no more leak memory
1964
1965 use Tie::Hash;
1966 tie my %tied_hash => 'Tie::StdHash';
1967
1968 ...
1969
1970 # Used to leak memory every time local() was called,
1971 # in a loop this added up.
1972 local($tied_hash{Foo}) = 1;
1973
1974=item *
1975
159ad915 1976Localised hash elements (and %ENV) are correctly unlocalised to not to
136430a4 1977exist, if that's what they were.
0b2c215a
JH
1978
1979
1980 use Tie::Hash;
1981 tie my %tied_hash => 'Tie::StdHash';
1982
1983 ...
1984
1985 # Nothing has set the FOO element so far
1986
1987 { local $tied_hash{FOO} = 'Bar' }
1988
1989 # Here the FOO element would have been C<undef>,
1990 # but no more so.
1991
1992As a side effect of this fix, tied hash interfaces B<must> define
159ad915 1993the EXISTS and DELETE methods.
0b2c215a
JH
1994
1995=item *
1996
e1f170bd
JH
1997mkdir() now ignores trailing slashes in the directory name,
1998as mandated by POSIX.
f39f21d8
JH
1999
2000=item *
2001
e1f170bd
JH
2002Some versions of glibc have a broken modfl(). This affects builds
2003with C<-Duselongdouble>. This version of Perl detects this brokenness
2004and has a workaround for it. The glibc release 2.2.2 is known to have
2005fixed the modfl() bug.
f39f21d8
JH
2006
2007=item *
2008
e1f170bd
JH
2009Modulus of unsigned numbers now works (4063328477 % 65535 used to
2010return 27406, instead of 27047).
f39f21d8
JH
2011
2012=item *
2013
e1f170bd
JH
2014Some "not a number" warnings introduced in 5.6.0 eliminated to be
2015more compatible with 5.005. Infinity is now recognised as a number.
f39f21d8 2016
77c8cf41 2017=item *
f39f21d8 2018
44da0e71
JH
2019Numeric conversions did not recognize changes in the string value
2020properly in certain circumstances.
2021
2022=item *
2023
e1f170bd 2024Attributes (like :shared) didn't work with our().
f39f21d8
JH
2025
2026=item *
2027
e1f170bd 2028our() variables will not cause "will not stay shared" warnings.
f39f21d8
JH
2029
2030=item *
2031
44da0e71
JH
2032"our" variables of the same name declared in two sibling blocks
2033resulted in bogus warnings about "redeclaration" of the variables.
2034The problem has been corrected.
2035
2036=item *
2037
e1f170bd 2038pack "Z" now correctly terminates the string with "\0".
f39f21d8
JH
2039
2040=item *
2041
e1f170bd
JH
2042Fix password routines which in some shadow password platforms
2043(e.g. HP-UX) caused getpwent() to return every other entry.
f39f21d8 2044
77c8cf41 2045=item *
f39f21d8 2046
e1f170bd
JH
2047The PERL5OPT environment variable (for passing command line arguments
2048to Perl) didn't work for more than a single group of options.
f39f21d8 2049
77c8cf41 2050=item *
f39f21d8 2051
e1f170bd 2052PERL5OPT with embedded spaces didn't work.
f39f21d8 2053
77c8cf41 2054=item *
f39f21d8 2055
e1f170bd 2056printf() no longer resets the numeric locale to "C".
f39f21d8 2057
77c8cf41 2058=item *
f39f21d8 2059
44da0e71
JH
2060C<qw(a\\b)> now parses correctly as C<'a\\b'>.
2061
2062=item *
2063
2064pos() did not return the correct value within s///ge in earlier
2065versions. This is now handled correctly.
f39f21d8 2066
77c8cf41 2067=item *
f39f21d8 2068
e1f170bd
JH
2069Printing quads (64-bit integers) with printf/sprintf now works
2070without the q L ll prefixes (assuming you are on a quad-capable platform).
f39f21d8 2071
77c8cf41 2072=item *
f39f21d8 2073
e1f170bd 2074Regular expressions on references and overloaded scalars now work.
f39f21d8 2075
ba370e9b
JH
2076=item *
2077
e1f170bd
JH
2078Right-hand side magic (GMAGIC) could in many cases such as string
2079concatenation be invoked too many times.
ba370e9b
JH
2080
2081=item *
2082
e1f170bd 2083scalar() now forces scalar context even when used in void context.
ba370e9b
JH
2084
2085=item *
2086
e1f170bd 2087SOCKS support is now much more robust.
ba370e9b
JH
2088
2089=item *
2090
e1f170bd
JH
2091sort() arguments are now compiled in the right wantarray context
2092(they were accidentally using the context of the sort() itself).
44da0e71
JH
2093The comparison block is now run in scalar context, and the arguments
2094to be sorted are always provided list context.
ba370e9b
JH
2095
2096=item *
2097
e1f170bd 2098Changed the POSIX character class C<[[:space:]]> to include the (very
c2e23569
JH
2099rarely used) vertical tab character. Added a new POSIX-ish character
2100class C<[[:blank:]]> which stands for horizontal whitespace
2101(currently, the space and the tab).
ba370e9b
JH
2102
2103=item *
2104
2105The tainting behaviour of sprintf() has been rationalized. It does
2106not taint the result of floating point formats anymore, making the
2107behaviour consistent with that of string interpolation.
2108
2109=item *
2110
44da0e71
JH
2111Some cases of inconsistent taint propagation (such as within hash
2112values) have been fixed.
2113
2114=item *
2115
2116The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
2117of simple pattern matches. These are now handled better.
2118
2119=item *
2120
2121Regular expression debug output (whether through C<use re 'debug'>
2122or via C<-Dr>) now looks better.
2123
2124=item *
2125
2126Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
2127bug has been fixed.
2128
2129=item *
2130
2131Use of $& could trigger a core dump under some situations. This
2132is now avoided.
2133
2134=item *
2135
c2e23569
JH
2136The regular expression captured submatches ($1, $2, ...) are now
2137more consistently unset if the match fails, instead of leaving false
2138data lying around in them.
2139
2140=item *
2141
44da0e71
JH
2142readline() on files opened in "slurp" mode could return an extra "" at
2143the end in certain situations. This has been corrected.
2144
2145=item *
2146
2147Autovivification of symbolic references of special variables described
2148in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
2149again now.
2150
2151=item *
2152
da6838c8 2153Sys::Syslog ignored the C<LOG_AUTH> constant.
ba370e9b
JH
2154
2155=item *
2156
e1f170bd 2157All but the first argument of the IO syswrite() method are now optional.
ba370e9b
JH
2158
2159=item *
2160
e1f170bd
JH
2161$AUTOLOAD, sort(), lock(), and spawning subprocesses
2162in multiple threads simultaneously are now thread-safe.
ba370e9b
JH
2163
2164=item *
2165
e1f170bd 2166Tie::ARRAY SPLICE method was broken.
ba370e9b
JH
2167
2168=item *
2169
e1f170bd 2170Allow read-only string on left hand side of non-modifying tr///.
ba370e9b
JH
2171
2172=item *
2173
ed788108
AT
2174If C<STDERR> is tied, warnings caused by C<warn> and C<die> now
2175correctly pass to it.
2176
2177=item *
2178
e1f170bd 2179Several Unicode fixes.
ba370e9b
JH
2180
2181=over 8
2182
2183=item *
2184
e1f170bd
JH
2185BOMs (byte order marks) in the beginning of Perl files
2186(scripts, modules) should now be transparently skipped.
2187UTF-16 (UCS-2) encoded Perl files should now be read correctly.
ba370e9b
JH
2188
2189=item *
2190
26f08e12 2191The character tables have been updated to Unicode 3.2.0.
ba370e9b
JH
2192
2193=item *
2194
e1f170bd 2195Comparing with utf8 data does not magically upgrade non-utf8 data
58175c9b
JH
2196into utf8. (This was a problem for example if you were mixing data
2197from I/O and Unicode data: your output might have got magically encoded
2198as UTF-8.)
2199
2200=item *
2201
2202Generating illegal Unicode code points like U+FFFE, or the UTF-16
2203surrogates, now also generates an optional warning.
ba370e9b
JH
2204
2205=item *
2206
e1f170bd 2207C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
f39f21d8 2208
77c8cf41 2209=item *
f39f21d8 2210
e1f170bd
JH
2211Concatenation with the C<.> operator or via variable interpolation,
2212C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
2213substitution with C<s///>, single-quoted UTF8, should now work.
f39f21d8 2214
77c8cf41 2215=item *
f39f21d8 2216
e1f170bd
JH
2217The C<tr///> operator now works. Note that the C<tr///CU>
2218functionality has been removed (but see pack('U0', ...)).
f39f21d8 2219
77c8cf41 2220=item *
f39f21d8 2221
e1f170bd 2222C<eval "v200"> now works.
f39f21d8 2223
77c8cf41 2224=item *
f39f21d8 2225
44da0e71
JH
2226Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
2227This has been corrected.
2228
2229=item *
2230
e1f170bd 2231Zero entries were missing from the Unicode classes like C<IsDigit>.
f39f21d8 2232
e1f170bd 2233=back
f39f21d8 2234
44da0e71
JH
2235=item *
2236
2237Large unsigned numbers (those above 2**31) could sometimes lose their
2238unsignedness, causing bogus results in arithmetic operations.
2239
77c8cf41 2240=back
f39f21d8 2241
77c8cf41 2242=head2 Platform Specific Changes and Fixes
f39f21d8
JH
2243
2244=over 4
2245
2246=item *
2247
77c8cf41 2248BSDI 4.*
f39f21d8 2249
77c8cf41 2250Perl now works on post-4.0 BSD/OSes.
f39f21d8
JH
2251
2252=item *
2253
77c8cf41 2254All BSDs
f39f21d8 2255
057b7f2b 2256Setting C<$0> now works (as much as possible; see L<perlvar> for details).
f39f21d8
JH
2257
2258=item *
2259
77c8cf41 2260Cygwin
f39f21d8 2261
439f2f5c 2262Numerous updates; currently synchronised with Cygwin 1.3.10.
f39f21d8
JH
2263
2264=item *
2265
e1f170bd
JH
2266Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
2267
2268=item *
2269
77c8cf41 2270EPOC
f39f21d8 2271
77c8cf41 2272EPOC update after Perl 5.6.0. See README.epoc.
f39f21d8
JH
2273
2274=item *
2275
77c8cf41 2276FreeBSD 3.*
f39f21d8 2277
77c8cf41 2278Perl now works on post-3.0 FreeBSDs.
f39f21d8
JH
2279
2280=item *
2281
77c8cf41
JH
2282HP-UX
2283
439f2f5c 2284README.hpux updated; C<Configure -Duse64bitall> now works.
f39f21d8
JH
2285
2286=item *
2287
77c8cf41 2288IRIX
f39f21d8 2289
77c8cf41
JH
2290Numerous compilation flag and hint enhancements; accidental mixing
2291of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
f39f21d8 2292
77c8cf41 2293=item *
f39f21d8 2294
77c8cf41 2295Linux
f39f21d8 2296
e1f170bd
JH
2297=over 8
2298
2299=item *
2300
77c8cf41 2301Long doubles should now work (see INSTALL).
f39f21d8
JH
2302
2303=item *
2304
e1f170bd
JH
2305Linux previously had problems related to sockaddrlen when using
2306accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
2307
2308=back
2309
2310=item *
2311
77c8cf41 2312MacOS Classic
f39f21d8 2313
77c8cf41
JH
2314Compilation of the standard Perl distribution in MacOS Classic should
2315now work if you have the Metrowerks development environment and
2316the missing Mac-specific toolkit bits. Contact the macperl mailing
2317list for details.
f39f21d8
JH
2318
2319=item *
2320
77c8cf41 2321MPE/iX
f39f21d8 2322
77c8cf41 2323MPE/iX update after Perl 5.6.0. See README.mpeix.
f39f21d8
JH
2324
2325=item *
2326
27cc4b77
JH
2327NetBSD/threads: try installing the GNU pth (should be in the
2328packages collection, or http://www.gnu.org/software/pth/),
2329and Configure with -Duseithreads.
2330
2331=item *
2332
77c8cf41 2333NetBSD/sparc
f39f21d8 2334
77c8cf41 2335Perl now works on NetBSD/sparc.
f39f21d8
JH
2336
2337=item *
2338
77c8cf41 2339OS/2
f39f21d8 2340
77c8cf41 2341Now works with usethreads (see INSTALL).
f39f21d8
JH
2342
2343=item *
2344
77c8cf41 2345Solaris
f39f21d8 2346
77c8cf41 234764-bitness using the Sun Workshop compiler now works.
f39f21d8
JH
2348
2349=item *
2350
11d33b1d
PG
2351Stratus VOS
2352
2353The native build method requires at least VOS Release 14.5.0
2354and GNU C++/GNU Tools 2.0.1 or later. The Perl pack function
2355now maps overflowed values to +infinity and underflowed values
2356to -infinity.
2357
2358=item *
2359
77c8cf41 2360Tru64 (aka Digital UNIX, aka DEC OSF/1)
f39f21d8 2361
77c8cf41
JH
2362The operating system version letter now recorded in $Config{osvers}.
2363Allow compiling with gcc (previously explicitly forbidden). Compiling
2364with gcc still not recommended because buggy code results, even with
2365gcc 2.95.2.
f39f21d8
JH
2366
2367=item *
2368
77c8cf41
JH
2369Unicos
2370
2371Fixed various alignment problems that lead into core dumps either
2372during build or later; no longer dies on math errors at runtime;
2373now using full quad integers (64 bits), previously was using
2374only 46 bit integers for speed.
f39f21d8
JH
2375
2376=item *
2377
77c8cf41
JH
2378VMS
2379
2380chdir() now works better despite a CRT bug; now works with MULTIPLICITY
2381(see INSTALL); now works with Perl's malloc.
f39f21d8 2382
00bb525a
CB
2383The tainting of C<%ENV> elements via C<keys> or C<values> was previously
2384unimplemented. It now works as documented.
2385
2386The C<waitpid> emulation has been improved. The worst bug (now fixed)
2387was that a pid of -1 would cause a wildcard search of all processes on
2388the system. The most significant enhancement is that we can now
2389usually get the completion status of a terminated process.
2390
2391POSIX-style signals are now emulated much better on VMS versions prior
2392to 7.0.
2393
2394The C<system> function and backticks operator have improved
2395functionality and better error handling.
2396
161720b2
CB
2397File access tests now use current process privileges rather than the
2398user's default privileges, which could sometimes result in a mismatch
2399between reported access and actual access.
2400
f39f21d8
JH
2401=item *
2402
77c8cf41 2403Windows
f39f21d8 2404
77c8cf41 2405=over 8
f39f21d8
JH
2406
2407=item *
2408
77c8cf41 2409accept() no longer leaks memory.
f39f21d8
JH
2410
2411=item *
2412
e1f170bd
JH
2413Borland C++ v5.5 is now a supported compiler that can build Perl.
2414However, the generated binaries continue to be incompatible with those
2415generated by the other supported compilers (GCC and Visual C++).
2416
2417=item *
2418
77c8cf41 2419Better chdir() return value for a non-existent directory.
f39f21d8 2420
77c8cf41 2421=item *
f39f21d8 2422
e1f170bd
JH
2423Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
2424
2425=item *
2426
77c8cf41 2427New %ENV entries now propagate to subprocesses.
f39f21d8
JH
2428
2429=item *
2430
44da0e71
JH
2431Current directory entries in %ENV are now correctly propagated to child
2432processes.
2433
2434=item *
2435
77c8cf41
JH
2436$ENV{LIB} now used to search for libs under Visual C.
2437
2438=item *
2439
44da0e71
JH
2440fork() emulation has been improved in various ways, but still continues
2441to be experimental. See L<perlfork> for known bugs and caveats.
e1f170bd
JH
2442
2443=item *
2444
77c8cf41 2445A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
f39f21d8
JH
2446
2447=item *
2448
44da0e71
JH
2449Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
2450Other bugs in chdir() and Cwd::cwd() have also been fixed.
2451
2452=item *
2453
e1f170bd
JH
2454HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
2455
2456=item *
2457
2458The makefiles now provide a single switch to bulk-enable all the features
2459enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
2460
2461=item *
2462
77c8cf41 2463Allow REG_EXPAND_SZ keys in the registry.
f39f21d8
JH
2464
2465=item *
2466
77c8cf41 2467Can now send() from all threads, not just the first one.
f39f21d8
JH
2468
2469=item *
2470
77c8cf41 2471Fake signal handling reenabled, bugs and all.
f39f21d8
JH
2472
2473=item *
2474
44da0e71
JH
2475%SIG has been enabled under USE_ITHREADS, but its use is completely
2476unsupported under all configurations.
2477
2478=item *
2479
77c8cf41
JH
2480Less stack reserved per thread so that more threads can run
2481concurrently. (Still 16M per thread.)
f39f21d8
JH
2482
2483=item *
2484
c2e23569 2485C<File::Spec-&gt;tmpdir()> now prefers C:/temp over /tmp
77c8cf41 2486(works better when perl is running as service).
f39f21d8
JH
2487
2488=item *
2489
77c8cf41 2490Better UNC path handling under ithreads.
f39f21d8
JH
2491
2492=item *
2493
44da0e71
JH
2494wait(), waitpid() and backticks now return the correct exit status under
2495Windows 9x.
f39f21d8
JH
2496
2497=item *
2498
77c8cf41 2499winsock handle leak fixed.
f39f21d8 2500
d1eb8299
YST
2501=item *
2502
2503The Perl parser has been stress tested using both random input and
2504Markov chain input and the few found crashes and lockups have been
2505fixed.
2506
f39f21d8
JH
2507=back
2508
77c8cf41 2509=back
f39f21d8 2510
77c8cf41 2511=head1 New or Changed Diagnostics
f39f21d8 2512
ba370e9b
JH
2513=over 4
2514
2515=item *
2516
12bcd1a6
PM
2517The lexical warnings category "deprecated" is no longer a sub-category
2518of the "syntax" category. It is now a top-level category in its own
2519right.
2520
2521=item *
2522
77c8cf41
JH
2523All regular expression compilation error messages are now hopefully
2524easier to understand both because the error message now comes before
2525the failed regex and because the point of failure is now clearly
ba370e9b
JH
2526marked by a C<E<lt>-- HERE> marker.
2527
2528=item *
f39f21d8 2529
77c8cf41
JH
2530The various "opened only for", "on closed", "never opened" warnings
2531drop the C<main::> prefix for filehandles in the C<main> package,
bea4d472 2532for example C<STDIN> instead of C<main::STDIN>.
f39f21d8 2533
ba370e9b
JH
2534=item *
2535
77c8cf41
JH
2536The "Unrecognized escape" warning has been extended to include C<\8>,
2537C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
f39f21d8 2538
ba370e9b 2539=item *
f39f21d8 2540
77c8cf41
JH
2541Two new debugging options have been added: if you have compiled your
2542Perl with debugging, you can use the -DT and -DR options to trace
2543tokenising and to add reference counts to displaying variables,
2544respectively.
f39f21d8
JH
2545
2546=item *
2547
2bcb0b45
JH
2548The debugger (perl5db.pl) has been modified to present a more
2549consistent commands interface, via (CommandSet=580). perl5db.t was
2550also added to test the changes, and as a placeholder for further tests.
492652be 2551
2bcb0b45 2552See L<perldebug>.
492652be
RF
2553
2554=item *
2555
9000bd02
MJD
2556The debugger has a new C<dumpDepth> option to control the maximum
2557depth to which nested structures are dumped. The C<x> command has
2558been extended so that C<x N EXPR> dumps out the value of I<EXPR> to a
2559depth of at most I<N> levels.
2560
2561=item *
2562
2bcb0b45
JH
2563The debugger can now show lexical variables if you have the CPAN
2564module PadWalker installed.
2565
2566=item *
2567
77c8cf41
JH
2568If an attempt to use a (non-blessed) reference as an array index
2569is made, a warning is given.
f39f21d8
JH
2570
2571=item *
2572
77c8cf41 2573C<push @a;> and C<unshift @a;> (with no values to push or unshift)
6e6372ba 2574now give a warning. This may be a problem for generated and evaled
77c8cf41 2575code.
f39f21d8 2576
ba370e9b
JH
2577=item *
2578
2579If you try to L<perlfunc/pack> a number less than 0 or larger than 255
2580using the C<"C"> format you will get an optional warning. Similarly
2581for the C<"c"> format and a number less than -128 or more than 127.
2582
2583=item *
2584
2585Certain regex modifiers such as C<(?o)> make sense only if applied to
0d4213c3
MJD
2586the entire regex. You will get an optional warning if you try to do
2587otherwise.
ba370e9b
JH
2588
2589=item *
2590
0d4213c3 2591Using arrays or hashes as references (e.g. C<< %foo->{bar} >>
c2e23569 2592has been deprecated for a while. Now you will get an optional warning.
ba370e9b 2593
608dbdb1
RGS
2594=item *
2595
2596Using C<sort> in scalar context now issues an optional warning.
2597This didn't do anything useful, as the sort was not performed.
2598
f39f21d8
JH
2599=back
2600
77c8cf41 2601=head1 Changed Internals
f39f21d8
JH
2602
2603=over 4
2604
2605=item *
2606
77c8cf41
JH
2607perlapi.pod (a companion to perlguts) now attempts to document the
2608internal API.
f39f21d8
JH
2609
2610=item *
2611
77c8cf41
JH
2612You can now build a really minimal perl called microperl.
2613Building microperl does not require even running Configure;
2614C<make -f Makefile.micro> should be enough. Beware: microperl makes
2615many assumptions, some of which may be too bold; the resulting
2616executable may crash or otherwise misbehave in wondrous ways.
2617For careful hackers only.
f39f21d8
JH
2618
2619=item *
2620
c2e23569
JH
2621Added rsignal(), whichsig(), do_join(), op_clear, op_null,
2622ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
2623interfaces to the publicised API. For the full list of the available
2624APIs see L<perlapi>.
f39f21d8
JH
2625
2626=item *
2627
77c8cf41 2628Made possible to propagate customised exceptions via croak()ing.
f39f21d8 2629
77c8cf41 2630=item *
f39f21d8 2631
95f0a2f1
SB
2632Now xsubs can have attributes just like subs. (Well, at least the
2633built-in attributes.)
f39f21d8
JH
2634
2635=item *
2636
77c8cf41
JH
2637dTHR and djSP have been obsoleted; the former removed (because it's
2638a no-op) and the latter replaced with dSP.
f39f21d8
JH
2639
2640=item *
2641
61947107
JH
2642PERL_OBJECT has been completely removed.
2643
2644=item *
2645
ba370e9b
JH
2646The MAGIC constants (e.g. C<'P'>) have been macrofied
2647(e.g. C<PERL_MAGIC_TIED>) for better source code readability
2648and maintainability.
2649
2650=item *
2651
2652The regex compiler now maintains a structure that identifies nodes in
2653the compiled bytecode with the corresponding syntactic features of the
2654original regex expression. The information is attached to the new
2655C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
2656complete information.
2657
2658=item *
2659
2660The C code has been made much more C<gcc -Wall> clean. Some warning
2661messages still remain in some platforms, so if you are compiling with
2662gcc you may see some warnings about dubious practices. The warnings
2663are being worked on.
2664
2665=item *
2666
2667F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
2668
2669=item *
2670
61947107
JH
2671Documentation on how to use the Perl source repository has been added
2672to F<Porting/repository.pod>.
f39f21d8 2673
888aee59
JH
2674=item *
2675
c2e23569 2676There are now several profiling make targets.
888aee59 2677
77c8cf41 2678=back
f39f21d8 2679
77c8cf41 2680=head1 Security Vulnerability Closed
f39f21d8 2681
77c8cf41 2682(This change was already made in 5.7.0 but bears repeating here.)
f39f21d8 2683
77c8cf41
JH
2684A potential security vulnerability in the optional suidperl component
2685of Perl was identified in August 2000. suidperl is neither built nor
2686installed by default. As of November 2001 the only known vulnerable
2687platform is Linux, most likely all Linux distributions. CERT and
2688various vendors and distributors have been alerted about the vulnerability.
2689See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
2690for more information.
f39f21d8 2691
77c8cf41
JH
2692The problem was caused by Perl trying to report a suspected security
2693exploit attempt using an external program, /bin/mail. On Linux
2694platforms the /bin/mail program had an undocumented feature which
2695when combined with suidperl gave access to a root shell, resulting in
2696a serious compromise instead of reporting the exploit attempt. If you
2697don't have /bin/mail, or if you have 'safe setuid scripts', or if
2698suidperl is not installed, you are safe.
f39f21d8 2699
77c8cf41
JH
2700The exploit attempt reporting feature has been completely removed from
2701Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
2702from all the Perl 5.7 releases), so that particular vulnerability
2703isn't there anymore. However, further security vulnerabilities are,
ba370e9b
JH
2704unfortunately, always possible. The suidperl functionality is most
2705probably going to be removed in Perl 5.10. In any case, suidperl
2706should only be used by security experts who know exactly what they are
2707doing and why they are using suidperl instead of some other solution
1577cd80 2708such as sudo ( see http://www.courtesan.com/sudo/ ).
77c8cf41
JH
2709
2710=head1 New Tests
2711
76663d67 2712Several new tests have been added, especially for the F<lib>
d1eb8299
YST
2713subsection. There are now about 56 000 individual tests (spread over
2714about 620 test scripts), in the regression suite (5.6.1 has about
76663d67
JH
271511700 tests, in 258 test scripts) Many of the new tests are introduced
2716by the new modules, but still in general Perl is now more thoroughly
2717tested.
2718
2719Because of the large number of tests, running the regression suite
2720will take considerably longer time than it used to: expect the suite
2721to take up to 4-5 times longer to run than in perl 5.6. In a really
d1eb8299 2722fast machine you can hope to finish the suite in about 6-8 minutes
76663d67 2723(wallclock time).
77c8cf41
JH
2724
2725The tests are now reported in a different order than in earlier Perls.
2726(This happens because the test scripts from under t/lib have been moved
2727to be closer to the library/extension they are testing.)
2728
f39f21d8
JH
2729=head1 Known Problems
2730
f39f21d8
JH
2731=head2 AIX
2732
2733=over 4
2734
2735=item *
2736
2737In AIX 4.2 Perl extensions that use C++ functions that use statics
2738may have problems in that the statics are not getting initialized.
2739In newer AIX releases this has been solved by linking Perl with
2740the libC_r library, but unfortunately in AIX 4.2 the said library
2741has an obscure bug where the various functions related to time
2742(such as time() and gettimeofday()) return broken values, and
2743therefore in AIX 4.2 Perl is not linked against the libC_r.
2744
2745=item *
2746
2747vac 5.0.0.0 May Produce Buggy Code For Perl
2748
2749The AIX C compiler vac version 5.0.0.0 may produce buggy code,
2750resulting in few random tests failing, but when the failing tests
2751are run by hand, they succeed. We suggest upgrading to at least
2752vac version 5.0.1.0, that has been known to compile Perl correctly.
439f2f5c 2753"lslpp -L|grep vac.C" will tell you the vac version. See README.aix.
f39f21d8 2754
0ea5284e
JH
2755=item *
2756
2757If building threaded Perl, you may get compilation warning from pp_sys.c:
2758
2759 "pp_sys.c", line 4651.39: 1506-280 (W) Function argument assignment between types "unsigned char*" and "const void*" is not allowed.
2760
2761This is harmless; it is caused by the getnetbyaddr() and getnetbyaddr_r()
2762having slightly different types for their first argument.
2763
f39f21d8
JH
2764=back
2765
2766=head2 Amiga Perl Invoking Mystery
2767
2768One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
057b7f2b 2769works, but for example C<bin:perl -v> doesn't. The exact reason isn't
f39f21d8
JH
2770known but the current suspect is the F<ixemul> library.
2771
bdcfa4c7
JH
2772=head2 ext/threads/t/libc
2773
2774If this test fails, it indicates that your libc (C library) is not
2775threadsafe. This particular test stress tests the localtime() call to
2776find out whether it is threadsafe. See L<perlthrtut> for more information.
2777
9ffc0d0c
JH
2778=head2 FreeBSD Failing locale Test 117 For ISO8859-15 Locales
2779
2780The ISO8859-15 locales may fail the locale test 117 in FreeBSD.
2781This is caused by the characters \xFF (y with diaeresis) and \xBE
2782(Y with diaeresis) not behaving correctly when being matched
2783case-insensitively.
2784
be61827f
JH
2785=head2 Modifying $_ Inside for(..)
2786
2787 for (1..5) { $_++ }
2788
2789works without complaint. It shouldn't. (You should be able to
2790modify only lvalue elements inside the loops.) You can see the
2791correct behaviour by replacing the 1..5 with 1, 2, 3, 4, 5.
2792
696235b6
JH
2793=head2 mod_perl 1.26 Doesn't Build With Threaded Perl
2794
2795Use mod_perl 1.27 or higher.
a08f42e9 2796
f39f21d8
JH
2797=head2 lib/ftmp-security tests warn 'system possibly insecure'
2798
2799Don't panic. Read INSTALL 'make test' section instead.
2800
be61827f 2801=head2 HP-UX lib/posix Subtest 9 Fails When LP64-Configured
f39f21d8
JH
2802
2803If perl is configured with -Duse64bitall, the successful result of the
2804subtest 10 of lib/posix may arrive before the successful result of the
2805subtest 9, which confuses the test harness so much that it thinks the
2806subtest 9 failed.
2807
2808=head2 Linux With Sfio Fails op/misc Test 48
2809
2810No known fix.
2811
a0aae13b
JH
2812=head2 Mac OS X
2813
6aaad45d
JH
2814Please remember to set your environment variable LC_ALL to "C"
2815(setenv LC_ALL C) before running "make test" to avoid a lot of
2816warnings about the broken locales of Mac OS X.
2817
a0aae13b
JH
2818The following tests are known to fail:
2819
2820 Failed Test Stat Wstat Total Fail Failed List of Failed
2821 -------------------------------------------------------------------------
2822 ../ext/DB_File/t/db-btree.t 0 11 ?? ?? % ??
2823 ../ext/DB_File/t/db-recno.t 149 3 2.01% 61 63 65
a0aae13b 2824
3f1f789b 2825If you are building on a UFS partition, you will also probably see
f5dcdc4e
JH
2826t/op/stat.t subtest #9 fail. This is caused by Darwin's UFS not
2827supporting inode change time.
3f1f789b 2828
7830a95b
JH
2829Also the ext/POSIX/t/posix.t subtest #10 fails but it is skipped for
2830now because the failure is Apple's fault, not Perl's (blocked signals
2831are lost).
2832
2833If you Configure with ithreads, ext/threads/t/libc.t will fail, again
2834not Perl's fault-- the libc of Mac OS X is not threadsafe (in this
2835particular test the localtime() call is found to be threadunsafe.)
2836
7fc79a86 2837=head2 op/sprintf tests 91, 129, and 130
f39f21d8 2838
7fc79a86
JH
2839The op/sprintf tests 91, 129, and 130 are known to fail on some platforms.
2840Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
f39f21d8 2841
7fc79a86
JH
2842The test 91 is known to fail at QNX6 (nto), because C<sprintf '%e',0>
2843incorrectly produces C<0.000000e+0> instead of C<0.000000e+00>.
f39f21d8 2844
7fc79a86
JH
2845For the tests 129 and 130 the failing platforms do not comply with
2846the ANSI C Standard, line 19ff on page 134 of ANSI X3.159 1989 to
2847be exact. (They produce something other than "1" and "-1" when
2848formatting 0.6 and -0.6 using the printf format "%.0f", most often
2849they produce "0" and "-0".)
f39f21d8 2850
0646842f
JH
2851=head2 Solaris 2.5
2852
2853In case you are still using Solaris 2.5 (aka SunOS 5.5), you may
2854experience failures (the test core dumping) in lib/locale.t.
2855The suggested cure is to upgrade your Solaris.
2856
11d33b1d
PG
2857=head2 Stratus VOS
2858
2859When Perl is built using the native build process on VOS Release
286014.5.0 and GNU C++/GNU Tools 2.0.1, all attempted tests either
2861pass or result in TODO (ignored) failures.
2862
7fc79a86 2863=head2 Failure of Thread (5.005-style) tests
f39f21d8 2864
6ba475fe
JH
2865B<Note that support for 5.005-style threading is deprecated,
2866experimental and practically unsupported. In 5.10 it is expected
2867to be removed.>
f39f21d8
JH
2868
2869The following tests are known to fail due to fundamental problems in
2870the 5.005 threading implementation. These are not new failures--Perl
28715.005_0x has the same bugs, but didn't have these tests.
2872
6123004a
JH
2873 ../ext/List/Util/t/first.t 255 65280 7 4 57.14% 2 5-7
2874 ../lib/English.t 2 512 54 2 3.70% 2-3
2875 ../lib/Filter/Simple/t/data.t 6 3 50.00% 1-3
2876 ../lib/Filter/Simple/t/filter_onl 9 3 33.33% 1-2 5
2877 ../lib/autouse.t 10 1 10.00% 4
2878 op/flip.t 15 1 6.67% 15
fedd8cf1 2879
9972c7af
JH
2880These failures are unlikely to get fixed as the 5.005-style threads
2881are considered fundamentally broken. (Basically what happens is that
2882competing threads can corrupt shared global state.)
f39f21d8
JH
2883
2884=head2 UNICOS
2885
c0f17b39
JH
2886 Failed Test Stat Wstat Total Fail Failed List of Failed
2887 -------------------------------------------------------------------------
6123004a
JH
2888 ../lib/Math/Trig.t 26 1 3.85% 25
2889 ../lib/warnings.t 460 1 0.22% 425
6123004a
JH
2890 op/numconvert.t 1440 13 0.90% 208 509-510
2891 657-658 665-666 829-830 989-990 1149-1150
f39f21d8 2892
9972c7af
JH
2893The Trig and numconvert failures are caused by the slighly differing
2894(from IEEE) floating point implementation of UNICOS. The warnings
2895failure is also related: the test assumes a certain floating point
2896output format, this assumption fails in UNICOS.
2897
cb3f5972
JH
2898=head2 UNICOS/mk
2899
3d7e8424
JH
2900=over 4
2901
2902=item *
2903
cb3f5972
JH
2904During Configure the test
2905
2906 Guessing which symbols your C compiler and preprocessor define...
2907
2908will probably fail with error messages like
2909
2910 CC-20 cc: ERROR File = try.c, Line = 3
2911 The identifier "bad" is undefined.
2912
2913 bad switch yylook 79bad switch yylook 79bad switch yylook 79bad switch yylook 79#ifdef A29K
2914 ^
2915
2916 CC-65 cc: ERROR File = try.c, Line = 3
2917 A semicolon is expected at this point.
2918
2919This is caused by a bug in awk utility of UNICOS/mk. You can ignore
2920the error, but it does cause a slight problem: you cannot fully
2921benefit from the h2ph utility (see L<h2ph>) that can be used to
2922convert C headers to Perl libraries, mainly used to be able to access
2923from Perl the constants defined using C preprocessor, cpp. Because of
2924the above error parts of the converted headers will be invisible.
2925Luckily, these days the need for h2ph is rare.
2926
3d7e8424
JH
2927=item *
2928
2929If building Perl with the interpreter threads (ithreads), the
2930getgrent(), getgrnam(), and getgrgid() functions cannot return the
2931list of the group members due to a bug in the multithreaded support of
2932UNICOS/mk. What this means that in list context the functions will
2933return only three values, not four.
2934
2935=back
2936
f39f21d8
JH
2937=head2 UTS
2938
2939There are a few known test failures, see L<perluts>.
2940
2941=head2 VMS
2942
161720b2
CB
2943There should be no reported test failures with a default configuration,
2944though there are a number of tests marked TODO that point to areas
2945needing further debugging and/or porting work.
7207e29d 2946
f39f21d8
JH
2947=head2 Win32
2948
2949In multi-CPU boxes there are some problems with the I/O buffering:
cd34865e 2950some output may appear twice.
f39f21d8 2951
d34c32a4
JH
2952=head2 XML::Parser not working
2953
2954Use XML::Parser 2.31 or later.
2955
7fc79a86
JH
2956=head2 z/OS (OS/390)
2957
2958z/OS has rather many test failures but the situation is actually
2959better than it was in 5.6.0, it's just that so many new modules and
2960tests have been added.
2961
dad95037 2962 Failed Test Stat Wstat Total Fail Failed List of Failed
c151f1b7
JH
2963 ---------------------------------------------------------------------------
2964 ../ext/Data/Dumper/t/dumper.t 357 8 2.24% 311 314 325 327
84fad863 2965 331 333 337 339
7fc79a86 2966 ../ext/IO/lib/IO/t/io_unix.t 5 4 80.00% 2-5
e363f566 2967 ../ext/Storable/t/downgrade.t 12 3072 169 12 7.10% 14-15 46-47 78-79
60d6f83c 2968 110-111 150 161
84fad863 2969 ../lib/ExtUtils/t/Constant.t 121 30976 48 48 100.00% 1-48
7fc79a86 2970 ../lib/ExtUtils/t/Embed.t 9 9 100.00% 1-9
e363f566
JH
2971 op/pat.t 910 7 0.77% 665 776 785 832-
2972 834 845
7fc79a86
JH
2973 op/sprintf.t 224 3 1.34% 98 100 136
2974 op/tr.t 97 5 5.15% 63 71-74
dcdcee7d
JH
2975 uni/fold.t 780 6 0.77% 61 169 196 661
2976 710-711
7fc79a86 2977
9972c7af
JH
2978The dumper.t and downgrade.t are problems in the tests, the io_unix
2979and sprintf are problems in the USS (UDP sockets and printf formats).
2980The pat, tr, and fold are genuine Perl problems caused by EBCDIC (and
2981in the pat and fold cases, combining that with Unicode). The Constant
2982and Embed are probably problems in the tests (since they test Perl's
2983ability to build extensions, and that seems to be working reasonably well.)
2984
aecce728
JH
2985=head2 Localising Tied Arrays and Hashes Is Broken
2986
2987 local %tied_array;
2988
2989doesn't work as one would expect: the old value is restored
2990incorrectly.
2991
f39f21d8
JH
2992=head2 Self-tying of Arrays and Hashes Is Forbidden
2993
2994Self-tying of arrays and hashes is broken in rather deep and
2995hard-to-fix ways. As a stop-gap measure to avoid people from getting
2996frustrated at the mysterious results (core dumps, most often) it is
2997for now forbidden (you will get a fatal error even from an attempt).
2998
f39f21d8
JH
2999=head2 Building Extensions Can Fail Because Of Largefiles
3000
3001Some extensions like mod_perl are known to have issues with
3002`largefiles', a change brought by Perl 5.6.0 in which file offsets
3003default to 64 bits wide, where supported. Modules may fail to compile
3004at all or compile and work incorrectly. Currently there is no good
3005solution for the problem, but Configure now provides appropriate
3006non-largefile ccflags, ldflags, libswanted, and libs in the %Config
3007hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
3008having problems can try configuring themselves without the
3009largefileness. This is admittedly not a clean solution, and the
3010solution may not even work at all. One potential failure is whether
3011one can (or, if one can, whether it's a good idea) link together at
3012all binaries with different ideas about file offsets, all this is
3013platform-dependent.
3014
aecce728
JH
3015=head2 Unicode Support on EBCDIC Still Spotty
3016
3017Though mostly working, Unicode support still has problem spots on
3018EBCDIC platforms. One such known spot are the C<\p{}> and C<\P{}>
3019regular expression constructs for code points less than 256: the
3020pP are testing for Unicode code points, not knowing about EBCDIC.
3021
f39f21d8
JH
3022=head2 The Compiler Suite Is Still Experimental
3023
44da0e71
JH
3024The compiler suite is slowly getting better but it continues to be
3025highly experimental. Use in production environments is discouraged.
f39f21d8 3026
c4f1ce08 3027=head2 The Long Double Support Is Still Experimental
f39f21d8
JH
3028
3029The ability to configure Perl's numbers to use "long doubles",
3030floating point numbers of hopefully better accuracy, is still
3031experimental. The implementations of long doubles are not yet
3032widespread and the existing implementations are not quite mature
3033or standardised, therefore trying to support them is a rare
3034and moving target. The gain of more precision may also be offset
3035by slowdown in computations (more bits to move around, and the
3036operations are more likely to be executed by less optimised
3037libraries).
33a87e58 3038
c4f1ce08
JH
3039=head2 Seen In Perl 5.7 But Gone Now
3040
c4f1ce08
JH
3041C<Time::Piece> (previously known as C<Time::Object>) was removed
3042because it was felt that it didn't have enough value in it to be a
3043core module. It is still a useful module, though, and is available
3044from the CPAN.
3045
cc0fca54
GS
3046=head1 Reporting Bugs
3047
d4ad863d
JH
3048If you find what you think is a bug, you might check the articles
3049recently posted to the comp.lang.perl.misc newsgroup and the perl
f224927c
JH
3050bug database at http://bugs.perl.org/ There may also be
3051information at http://www.perl.com/ , the Perl Home Page.
cc0fca54
GS
3052
3053If you believe you have an unreported bug, please run the B<perlbug>
3054program included with your release. Be sure to trim your bug down
3055to a tiny but sufficient test case. Your bug report, along with the
d4ad863d 3056output of C<perl -V>, will be sent off to perlbug@perl.org to be
cc0fca54
GS
3057analysed by the Perl porting team.
3058
3059=head1 SEE ALSO
3060
3061The F<Changes> file for exhaustive details on what changed.
3062
3063The F<INSTALL> file for how to build Perl.
3064
3065The F<README> file for general stuff.
3066
3067The F<Artistic> and F<Copying> files for copyright information.
3068
3069=head1 HISTORY
3070
d468ca04 3071Written by Jarkko Hietaniemi <F<jhi@iki.fi>>.
cc0fca54
GS
3072
3073=cut