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perldeltify change #4115.
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1=head1 NAME
2
651a3225 3perldelta - what's new for perl v5.6 (as of v5.005_61)
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4
5=head1 DESCRIPTION
6
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7This is an unsupported alpha release, meant for intrepid Perl developers
8only. The included sources may not even build correctly on some platforms.
9Subscribing to perl5-porters is the best way to monitor and contribute
10to the progress of development releases (see www.perl.org for info).
11
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12This document describes differences between the 5.005 release and this one.
13
14=head1 Incompatible Changes
15
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16=head2 Perl Source Incompatibilities
17
f29c64d6 18TODO
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19
20=head2 C Source Incompatibilities
21
22=over 4
23
24=item C<PERL_POLLUTE>
25
26Release 5.005 grandfathered old global symbol names by providing preprocessor
87275199 27macros for extension source compatibility. As of release 5.6, these
e02fdbd2 28preprocessor definitions are not available by default. You need to explicitly
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29compile perl with C<-DPERL_POLLUTE> to get these definitions. For
30extensions still using the old symbols, this option can be
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31specified via MakeMaker:
32
14218588 33 perl Makefile.PL POLLUTE=1
e02fdbd2 34
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35=item C<PERL_IMPLICIT_CONTEXT>
36
37This new build option provides a set of macros for all API functions
38such that an implicit interpreter/thread context argument is passed to
39every API function. As a result of this, something like C<sv_setsv(foo,bar)>
2c2d71f5 40amounts to a macro invocation that actually translates to something like
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41C<Perl_sv_setsv(my_perl,foo,bar)>. While this is generally expected
42to not have any significant source compatibility issues, the difference
43between a macro and a real function call will need to be considered.
44
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45This means that there B<is> a source compatibility issue as a result of
46this if your extensions attempt to use pointers to any of the Perl API
47functions.
48
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49Note that the above issue is not relevant to the default build of
50Perl, whose interfaces continue to match those of prior versions
51(but subject to the other options described here).
52
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53PERL_IMPLICIT_CONTEXT is automatically enabled whenever Perl is built
54with one of -Dusethreads, -Dusemultiplicity, or both.
f29c64d6 55
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56See L<perlguts/"The Perl API"> for detailed information on the
57ramifications of building Perl using this option.
58
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59=item C<PERL_POLLUTE_MALLOC>
60
14218588 61Enabling Perl's malloc in release 5.005 and earlier caused
86058a2d 62the namespace of system versions of the malloc family of functions to
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63be usurped by the Perl versions, since by default they used the
64same names.
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65
66Besides causing problems on platforms that do not allow these functions to
67be cleanly replaced, this also meant that the system versions could not
68be called in programs that used Perl's malloc. Previous versions of Perl
14218588 69have allowed this behaviour to be suppressed with the HIDEMYMALLOC and
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70EMBEDMYMALLOC preprocessor definitions.
71
87275199 72As of release 5.6, Perl's malloc family of functions have default names
86058a2d 73distinct from the system versions. You need to explicitly compile perl with
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74C<-DPERL_POLLUTE_MALLOC> to get the older behaviour. HIDEMYMALLOC
75and EMBEDMYMALLOC have no effect, since the behaviour they enabled is now
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76the default.
77
78Note that these functions do B<not> constitute Perl's memory allocation API.
79See L<perlguts/"Memory Allocation"> for further information about that.
80
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81=item C<PL_na> and C<dTHR> Issues
82
83The C<PL_na> global is now thread local, so a C<dTHR> declaration is needed
14218588 84in the scope in which the global appears. XSUBs should handle this automatically,
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85but if you have used C<PL_na> in support functions, you either need to
86change the C<PL_na> to a local variable (which is recommended), or put in
87a C<dTHR>.
88
89=back
90
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91=head2 Compatible C Source API Changes
92
93=over
94
95=item C<PATCHLEVEL> is now C<PERL_VERSION>
96
14218588 97The cpp macros C<PERL_REVISION>, C<PERL_VERSION>, and C<PERL_SUBVERSION>
cceca5ed 98are now available by default from perl.h, and reflect the base revision,
14218588 99patchlevel, and subversion respectively. C<PERL_REVISION> had no
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100prior equivalent, while C<PERL_VERSION> and C<PERL_SUBVERSION> were
101previously available as C<PATCHLEVEL> and C<SUBVERSION>.
102
14218588 103The new names cause less pollution of the B<cpp> namespace and reflect what
cceca5ed 104the numbers have come to stand for in common practice. For compatibility,
14218588 105the old names are still supported when F<patchlevel.h> is explicitly
cceca5ed 106included (as required before), so there is no source incompatibility
14218588 107from the change.
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108
109=back
110
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111=head2 Binary Incompatibilities
112
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113The default build of this release is binary compatible with the 5.005
114release or its maintenance versions.
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115
116The usethreads or usemultiplicity builds are B<not> binary compatible
117with the corresponding builds in 5.005.
e02fdbd2 118
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119=head1 Core Changes
120
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121=head2 Unicode and UTF-8 support
122
123Perl can optionally use UTF-8 as its internal representation for character
124strings. The C<use utf8> pragma enables this support in the current lexical
125scope. See L<utf8> for more information.
126
127=head2 Lexically scoped warning categories
128
129You can now control the granularity of warnings emitted by perl at a finer
4438c4b7 130level using the C<use warnings> pragma. See L<warnings> and L<perllexwarn>
0453d815 131for details.
9d73390d 132
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133=head2 Binary numbers supported
134
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135Binary numbers are now supported as literals, in s?printf formats, and
136C<oct()>:
137
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138 $answer = 0b101010;
139 printf "The answer is: %b\n", oct("0b101010");
4f19785b 140
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141=head2 syswrite() ease-of-use
142
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143The length argument of C<syswrite()> is now optional.
144
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145=head2 64-bit support
146
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147All platforms that have 64-bit integers either (a) natively as longs
148or ints (b) via special compiler flags (c) using long long are able to
149use "quads" (64-integers) as follows:
150
151=over 4
152
1fad5d67 153=item constants (decimal, hexadecimal, octal, binary) in the code
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154
155=item arguments to oct() and hex()
156
1fad5d67 157=item arguments to print(), printf() and sprintf() (flag prefixes ll, L, q)
9c107f78 158
1fad5d67 159=item printed as such
9c107f78 160
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161=item pack() and unpack() "q" and "Q" formatS
162
163=item in basic arithmetics: + - * / %
9c107f78 164
d0ba1bd2 165=item vec() (but see the below note about bit arithmetics)
c5a0f51a 166
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167=back
168
169Note that unless you have the case (a) you will have to configure
170and compile Perl using the -Duse64bits Configure flag.
171
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172Unfortunately bit arithmetics (&, |, ^, ~, <<, >>) are not 64-bit clean,
173they are explictly forced to be 32-bit.
d0ba1bd2 174
2d4389e4 175Last but not least: note that due to Perl's habit of always using
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176floating point numbers the quads are still not true integers.
177When quads overflow their limits (0...18_446_744_073_709_551_615 unsigned,
178-9_223_372_036_854_775_808...9_223_372_036_854_775_807 signed), they
179are silently promoted to floating point numbers, after which they will
180start losing precision (their lower digits).
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181
182=head2 Large file support
183
184If you have filesystems that support "large files" (files larger than
1852 gigabytes), you may now also be able to create and access them from Perl.
186
187Note that in addition to requiring a proper file system to do this you
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188may also need to adjust your per-process (or even your per-system)
189maximum filesize limits before running Perl scripts that try to handle
190large files, especially if you intend to write such files.
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191
192Adjusting your file system/system limits is outside the scope of Perl.
193For process limits, you may try to increase the limits using your
194shell's limit/ulimit command before running Perl. The BSD::Resource
195extension (not included with the standard Perl distribution) may also
196be of use.
197
198(Large file support is also related to 64-bit support, for obvious reasons)
09bef843 199
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200=head2 Better syntax checks on parenthesized unary operators
201
202Expressions such as:
203
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204 print defined(&foo,&bar,&baz);
205 print uc("foo","bar","baz");
206 undef($foo,&bar);
62c18ce2 207
7711098a 208used to be accidentally allowed in earlier versions, and produced
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209unpredictable behaviour. Some produced ancillary warnings
210when used in this way; others silently did the wrong thing.
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211
212The parenthesized forms of most unary operators that expect a single
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213argument now ensure that they are not called with more than one
214argument, making the cases shown above syntax errors. The usual
215behaviour of:
62c18ce2 216
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217 print defined &foo, &bar, &baz;
218 print uc "foo", "bar", "baz";
219 undef $foo, &bar;
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220
221remains unchanged. See L<perlop>.
222
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223=head2 POSIX character class syntax [: :] supported
224
225For example to match alphabetic characters use /[[:alpha:]]/.
226See L<perlre> for details.
227
5a929a98 228=head2 Improved C<qw//> operator
8127e0e3 229
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230The C<qw//> operator is now evaluated at compile time into a true list
231instead of being replaced with a run time call to C<split()>. This
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232removes the confusing misbehaviour of C<qw//> in scalar context, which
233had inherited that behaviour from split().
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234
235Thus:
236
237 $foo = ($bar) = qw(a b c); print "$foo|$bar\n";
238
239now correctly prints "3|a", instead of "2|a".
8127e0e3 240
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241=head2 pack() format 'Z' supported
242
243The new format type 'Z' is useful for packing and unpacking null-terminated
244strings. See L<perlfunc/"pack">.
245
4d0c1c44 246=head2 pack() format modifier '!' supported
ee3907e2 247
14218588 248The new format type modifier '!' is useful for packing and unpacking
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249native shorts, ints, and longs. See L<perlfunc/"pack">.
250
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251=head2 pack() and unpack() support counted strings
252
253The template character '#' can be used to specify a counted string
254type to be packed or unpacked. See L<perlfunc/"pack">.
255
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256=head2 $^X variables may now have names longer than one character
257
258Formerly, $^X was synonymous with ${"\cX"}, but $^XY was a syntax
259error. Now variable names that begin with a control character may be
260arbitrarily long. However, for compatibility reasons, these variables
261I<must> be written with explicit braces, as C<${^XY}> for example.
14218588 262C<${^XYZ}> is synonymous with ${"\cXYZ"}. Variable names with more
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263than one control character, such as C<${^XY^Z}>, are illegal.
264
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265The old syntax has not changed. As before, `^X' may be either a
266literal control-X character or the two-character sequence `caret' plus
267`X'. When braces are omitted, the variable name stops after the
2b92dfce 268control character. Thus C<"$^XYZ"> continues to be synonymous with
7711098a 269C<$^X . "YZ"> as before.
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270
271As before, lexical variables may not have names beginning with control
272characters. As before, variables whose names begin with a control
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273character are always forced to be in package `main'. All such variables
274are reserved for future extensions, except those that begin with
09bef843 275C<^_>, which may be used by user programs and are guaranteed not to
14218588 276acquire special meaning in any future version of Perl.
2b92dfce 277
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278=head2 C<use attrs> implicit in subroutine attributes
279
280Formerly, if you wanted to mark a subroutine as being a method call or
281as requiring an automatic lock() when it is entered, you had to declare
282that with a C<use attrs> pragma in the body of the subroutine.
283That can now be accomplished with a declaration syntax, like this:
284
285 sub mymethod : locked, method ;
286 ...
287 sub mymethod : locked, method {
288 ...
289 }
290
291F<AutoSplit.pm> and F<SelfLoader.pm> have been updated to keep the attributes
292with the stubs they provide. See L<attributes>.
293
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294=head1 Significant bug fixes
295
296=head2 E<lt>HANDLEE<gt> on empty files
297
298With C<$/> set to C<undef>, slurping an empty file returns a string of
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299zero length (instead of C<undef>, as it used to) the first time the
300HANDLE is read. Further reads yield C<undef>.
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301
302This means that the following will append "foo" to an empty file (it used
14218588 303to do nothing):
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304
305 perl -0777 -pi -e 's/^/foo/' empty_file
306
14218588 307The behaviour of:
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308
309 perl -pi -e 's/^/foo/' empty_file
310
311is unchanged (it continues to leave the file empty).
312
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313=head2 C<eval '...'> improvements
314
315Line numbers (as reflected by caller() and most diagnostics) within
316C<eval '...'> were often incorrect when here documents were involved.
317This has been corrected.
318
319Lexical lookups for variables appearing in C<eval '...'> within
320functions that were themselves called within an C<eval '...'> were
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321searching the wrong place for lexicals. The lexical search now
322correctly ends at the subroutine's block boundary.
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323
324Parsing of here documents used to be flawed when they appeared as
325the replacement expression in C<eval 's/.../.../e'>. This has
326been fixed.
327
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328=head2 Automatic flushing of output buffers
329
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330fork(), exec(), system(), qx//, and pipe open()s now flush buffers
331of all files opened for output when the operation
332was attempted. This mostly eliminates confusing
45bc9206 333buffering mishaps suffered by users unaware of how Perl internally
14218588 334handles I/O.
45bc9206 335
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336=head2 Better diagnostics on meaningless filehandle operations
337
338Constructs such as C<open(E<lt>FHE<gt>)> and C<close(E<lt>FHE<gt>)>
339are compile time errors. Attempting to read from filehandles that
340were opened only for writing will now produce warnings (just as
341writing to read-only filehandles does).
342
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343=head2 Buffered data discarded from input filehandle when dup'ed.
344
345C<open(NEW, "E<lt>&OLD")> now discards any data that was previously
346read and buffered in C<OLD>. The next read operation on C<NEW> will
347return the same data as the corresponding operation on C<OLD>.
348Formerly, it would have returned the data from the start of the
349following disk block instead.
350
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351=head1 Supported Platforms
352
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353=over 4
354
355=item *
356
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357VM/ESA is now supported.
358
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359=item *
360
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361Siemens BS2000 is now supported under the POSIX Shell.
362
363=item *
364
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365The Mach CThreads (NEXTSTEP, OPENSTEP) are now supported by the Thread
366extension.
6c67e1bb 367
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368=item *
369
ee3907e2 370GNU/Hurd is now supported.
6c67e1bb 371
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372=item *
373
374Rhapsody is now supported.
375
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376=item *
377
378EPOC is is now supported (on Psion 5).
379
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380=back
381
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382=head1 New tests
383
384=over 4
385
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386=item lib/attrs
387
388Compatibility tests for C<sub : attrs> vs the older C<use attrs>.
389
390=item lib/io_const
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391
392IO constants (SEEK_*, _IO*).
14218588 393
09bef843 394=item lib/io_dir
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395
396Directory-related IO methods (new, read, close, rewind, tied delete).
397
09bef843 398=item lib/io_multihomed
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399
400INET sockets with multi-homed hosts.
401
09bef843 402=item lib/io_poll
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403
404IO poll().
405
09bef843 406=item lib/io_unix
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407
408UNIX sockets.
409
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410=item op/attrs
411
412Regression tests for C<my ($x,@y,%z) : attrs> and <sub : attrs>.
413
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414=item op/filetest
415
416File test operators.
417
418=item op/lex_assign
419
5fdc711f 420Verify operations that access pad objects (lexicals and temporaries).
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421
422=back
e02fdbd2 423
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424=head1 Modules and Pragmata
425
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426=head2 Modules
427
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428=over 4
429
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430=item attributes
431
432While used internally by Perl as a pragma, this module also
433provides a way to fetch subroutine and variable attributes.
434See L<attributes>.
435
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436=item ByteLoader
437
438The ByteLoader is a dedication extension to generate and run
439Perl bytecode. See L<ByteLoader>.
440
441=item B
442
443The Perl Compiler suite has been extensively reworked for this
444release.
445
446=item Devel::DProf
447
448Devel::DProf, a Perl source code profiler has been added.
449
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450=item Dumpvalue
451
452Added Dumpvalue module provides screen dumps of Perl data.
453
454=item Benchmark
455
868cb350 456You can now run tests for I<n> seconds instead of guessing the right
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457number of tests to run: e.g. timethese(-5, ...) will run each
458code for at least 5 CPU seconds. Zero as the "number of repetitions"
155776c0 459means "for at least 3 CPU seconds". The output format has also
14218588 460changed. For example:
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461
462use Benchmark;$x=3;timethese(-5,{a=>sub{$x*$x},b=>sub{$x**2}})
463
464will now output something like this:
465
466Benchmark: running a, b, each for at least 5 CPU seconds...
467 a: 5 wallclock secs ( 5.77 usr + 0.00 sys = 5.77 CPU) @ 200551.91/s (n=1156516)
468 b: 4 wallclock secs ( 5.00 usr + 0.02 sys = 5.02 CPU) @ 159605.18/s (n=800686)
469
470New features: "each for at least N CPU seconds...", "wallclock secs",
471and the "@ operations/CPU second (n=operations)".
b7d8191e 472
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473=item Devel::Peek
474
475The Devel::Peek module provides access to the internal representation
14218588 476of Perl variables and data. It is a data debugging tool for the XS programmer.
f505c983 477
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478=item Fcntl
479
480More Fcntl constants added: F_SETLK64, F_SETLKW64, O_LARGEFILE for
14218588 481large (more than 4G) file access (64-bit support is not yet
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482working, though, so no need to get overly excited), Free/Net/OpenBSD
483locking behaviour flags F_FLOCK, F_POSIX, Linux F_SHLCK, and
484O_ACCMODE: the mask of O_RDONLY, O_WRONLY, and O_RDWR.
485
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486=item File::Spec
487
488New methods have been added to the File::Spec module: devnull() returns
19799a22 489the name of the null device (/dev/null on Unix) and tmpdir() the name of
14218588 490the temp directory (normally /tmp on Unix). There are now also methods
f505c983 491to convert between absolute and relative filenames: abs2rel() and
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492rel2abs(). For compatibility with operating systems that specify volume
493names in file paths, the splitpath(), splitdir(), and catdir() methods
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494have been added.
495
496=item File::Spec::Functions
497
498The new File::Spec::Functions modules provides a function interface
14218588 499to the File::Spec module. Allows shorthand
f505c983 500
14218588 501 $fullname = catfile($dir1, $dir2, $file);
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502
503instead of
504
14218588 505 $fullname = File::Spec->catfile($dir1, $dir2, $file);
f505c983 506
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507=item Math::BigInt
508
14218588 509The logical operations C<E<lt>E<lt>>, C<E<gt>E<gt>>, C<&>, C<|>,
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510and C<~> are now supported on bigints.
511
b7d8191e 512=item Math::Complex
7711098a 513
14218588 514The accessor methods Re, Im, arg, abs, rho, and theta can now also
868cb350 515act as mutators (accessor $z->Re(), mutator $z->Re(3)).
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516
517=item Math::Trig
518
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519A little bit of radial trigonometry (cylindrical and spherical),
520radial coordinate conversions, and the great circle distance were added.
b7d8191e 521
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522=item SDBM_File
523
524An EXISTS method has been added to this module (and sdbm_exists() has
525been added to the underlying sdbm library), so one can now call exists
14218588 526on an SDBM_File tied hash and get the correct result, rather than a
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527runtime error.
528
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529=item Time::Local
530
531The timelocal() and timegm() functions used to silently return bogus
532results when the date exceeded the machine's integer range. They
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533now consistently croak() if the date falls in an unsupported range--
534but on the other hand they now accept "out-of-limits" day-of-month
535to make "Julian date" conversions easier.
06ef4121 536
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537=item Win32
538
539The error return value in list context has been changed for all functions
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540that return a list of values. Previously these functions returned a list
541with a single element C<undef> if an error occurred. Now these functions
542return the empty list in these situations. This applies to the following
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543functions:
544
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545 Win32::FsType
546 Win32::GetOSVersion
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547
548The remaining functions are unchanged and continue to return C<undef> on
549error even in list context.
550
551The Win32::SetLastError(ERROR) function has been added as a complement
552to the Win32::GetLastError() function.
553
554The new Win32::GetFullPathName(FILENAME) returns the full absolute
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555pathname for FILENAME in scalar context. In list context it returns
556a two-element list containing the fully qualified directory name and
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557the filename.
558
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559=item DBM Filters
560
561A new feature called "DBM Filters" has been added to all the
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562DBM modules--DB_File, GDBM_File, NDBM_File, ODBM_File, and SDBM_File.
563DBM Filters add four new methods to each DBM module:
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564
565 filter_store_key
566 filter_store_value
567 filter_fetch_key
568 filter_fetch_value
569
14218588 570These can be used to filter key-value pairs before the pairs are
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571written to the database or just after they are read from the database.
572See L<perldbmfilter> for further information.
573
b7d8191e 574=back
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575
576=head2 Pragmata
577
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578C<use attrs> is now obsolescent, and is only provided for
579backward-compatibility. It's been replaced by the C<sub : attributes>
580syntax. See L<perlsub/"Subroutine Attributes"> and L<attributes>.
581
14218588 582C<use utf8> to enable UTF-8 and Unicode support.
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583
584C<use caller 'encoding'> allows modules to inherit pragmatic attributes
585from the caller's context. C<encoding> is currently the only supported
586attribute.
9d73390d 587
4438c4b7 588Lexical warnings pragma, C<use warnings;>, to control optional warnings.
6c67e1bb 589
14218588 590C<use filetest> to control the behaviour of filetests (C<-r> C<-w> ...).
6c67e1bb 591Currently only one subpragma implemented, "use filetest 'access';",
14218588 592that enables the use of access(2) or equivalent to check
6c67e1bb 593permissions instead of using stat(2) as usual. This matters
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594in filesystems where there are ACLs (access control lists): the
595stat(2) might lie, but access(2) knows better.
6c67e1bb 596
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597=head1 Utility Changes
598
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599Todo.
600
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601=head1 Documentation Changes
602
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603=over 4
604
605=item perlopentut.pod
f8284313 606
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607A tutorial on using open() effectively.
608
609=item perlreftut.pod
610
611A tutorial that introduces the essentials of references.
612
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613=item perltootc.pod
614
615A tutorial on managing class data for object modules.
616
5fdc711f 617=back
e02fdbd2 618
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619=head1 New Diagnostics
620
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621=item "my sub" not yet implemented
622
623(F) Lexically scoped subroutines are not yet implemented. Don't try that
624yet.
625
626=item %s package attribute may clash with future reserved word: %s
627
628(W) A lowercase attribute name was used that had a package-specific handler.
629That name might have a meaning to Perl itself some day, even though it
630doesn't yet. Perhaps you should use a mixed-case attribute name, instead.
631See L<attributes>.
632
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633=item /%s/: Unrecognized escape \\%c passed through
634
635(W) You used a backslash-character combination which is not recognized
7711098a 636by Perl. This combination appears in an interpolated variable or a
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637C<'>-delimited regular expression.
638
af8c498a 639=item Filehandle %s opened only for output
6b121555 640
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641(W) You tried to read from a filehandle opened only for writing. If you
642intended it to be a read-write filehandle, you needed to open it with
643"+E<lt>" or "+E<gt>" or "+E<gt>E<gt>" instead of with "E<lt>" or nothing. If
644you intended only to read from the file, use "E<lt>". See
645L<perlfunc/open>.
e02fdbd2 646
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647=item Invalid %s attribute: %s
648
649The indicated attribute for a subroutine or variable was not recognized
650by Perl or by a user-supplied handler. See L<attributes>.
651
652=item Invalid %s attributes: %s
653
654The indicated attributes for a subroutine or variable were not recognized
655by Perl or by a user-supplied handler. See L<attributes>.
656
657=item Invalid separator character %s in attribute list
658
659(F) Something other than a comma or whitespace was seen between the
660elements of an attribute list. If the previous attribute
661had a parenthesised parameter list, perhaps that list was terminated
662too soon. See L<attributes>.
663
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664=item Missing command in piped open
665
666(W) You used the C<open(FH, "| command")> or C<open(FH, "command |")>
667construction, but the command was missing or blank.
668
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669=item Missing name in "my sub"
670
671(F) The reserved syntax for lexically scoped subroutines requires that they
672have a name with which they can be found.
673
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674=item Unrecognized escape \\%c passed through
675
676(W) You used a backslash-character combination which is not recognized
677by Perl.
678
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679=item Unterminated attribute parameter in attribute list
680
681(F) The lexer saw an opening (left) parenthesis character while parsing an
682attribute list, but the matching closing (right) parenthesis
683character was not found. You may need to add (or remove) a backslash
684character to get your parentheses to balance. See L<attributes>.
685
686=item Unterminated attribute list
687
688(F) The lexer found something other than a simple identifier at the start
689of an attribute, and it wasn't a semicolon or the start of a
690block. Perhaps you terminated the parameter list of the previous attribute
691too soon. See L<attributes>.
692
f10b0346 693=item defined(@array) is deprecated
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694
695(D) defined() is not usually useful on arrays because it checks for an
696undefined I<scalar> value. If you want to see if the array is empty,
697just use C<if (@array) { # not empty }> for example.
698
f10b0346 699=item defined(%hash) is deprecated
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700
701(D) defined() is not usually useful on hashes because it checks for an
702undefined I<scalar> value. If you want to see if the hash is empty,
703just use C<if (%hash) { # not empty }> for example.
704
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705=item Invalid separator character %s in subroutine attribute list
706
707(F) Something other than a comma or whitespace was seen between the
708elements of a subroutine attribute list. If the previous attribute
709had a parenthesised parameter list, perhaps that list was terminated
710too soon.
711
712=item Unterminated attribute parameter in subroutine attribute list
713
714(F) The lexer saw an opening (left) parenthesis character while parsing a
715subroutine attribute list, but the matching closing (right) parenthesis
716character was not found. You may need to add (or remove) a backslash
717character to get your parentheses to balance.
718
719=item Unterminated subroutine attribute list
720
721(F) The lexer found something other than a simple identifier at the start
722of a subroutine attribute, and it wasn't a semicolon or the start of a
723block. Perhaps you terminated the parameter list of the previous attribute
724too soon.
725
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726=item /%s/ should probably be written as "%s"
727
728(W) You have used a pattern where Perl expected to find a string,
729like in the first argument to C<join>. Perl will treat the true
730or false result of matching the pattern against $_ as the string,
731which is probably not what you had in mind.
732
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733=head1 Obsolete Diagnostics
734
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735Todo.
736
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737=head1 Configuration Changes
738
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739=head2 installusrbinperl
740
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741You can use "Configure -Uinstallusrbinperl" which causes installperl
742to skip installing perl also as /usr/bin/perl. This is useful if you
743prefer not to modify /usr/bin for some reason or another but harmful
744because many scripts assume to find Perl in /usr/bin/perl.
745
27806c82 746=head2 SOCKS support
555834d1 747
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748You can use "Configure -Dusesocks" which causes Perl to probe
749for the SOCKS proxy protocol library, http://www.socks.nec.com/
04d420f9 750
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751=head1 BUGS
752
753If you find what you think is a bug, you might check the headers of
14218588 754articles recently posted to the comp.lang.perl.misc newsgroup.
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755There may also be information at http://www.perl.com/perl/, the Perl
756Home Page.
757
758If you believe you have an unreported bug, please run the B<perlbug>
14218588 759program included with your release. Make sure to trim your bug down
ba8251e8 760to a tiny but sufficient test case. Your bug report, along with the
14218588 761output of C<perl -V>, will be sent off to perlbug@perl.com to be
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762analysed by the Perl porting team.
763
764=head1 SEE ALSO
765
766The F<Changes> file for exhaustive details on what changed.
767
768The F<INSTALL> file for how to build Perl.
769
770The F<README> file for general stuff.
771
772The F<Artistic> and F<Copying> files for copyright information.
773
774=head1 HISTORY
775
776Written by Gurusamy Sarathy <F<gsar@umich.edu>>, with many contributions
777from The Perl Porters.
778
779Send omissions or corrections to <F<perlbug@perl.com>>.
780
781=cut