Commit | Line | Data |
d468ca04 |
1 | =head1 NAME |
2 | |
3 | perl571delta - what's new for perl v5.7.1 |
4 | |
5 | =head1 DESCRIPTION |
6 | |
7 | This document describes differences between the 5.7.0 release and the |
8 | 5.7.1 release. |
9 | |
10 | (To view the differences between the 5.6.0 release and the 5.7.0 |
11 | release, see L<perl570delta>). |
12 | |
6a9b4349 |
13 | =head1 Security Vulnerability Closed |
14 | |
15 | (This change was already made in 5.7.0 but bears repeating here.) |
16 | |
17 | A potential security vulnerability in the optional suidperl component |
18 | of Perl was identified in August 2000. suidperl is neither built nor |
19 | installed by default. As of April 2001 the only known vulnerable |
20 | platform is Linux, most likely all Linux distributions. CERT and |
21 | various vendors and distributors have been alerted about the vulnerability. |
22 | See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt |
23 | for more information. |
24 | |
25 | The problem was caused by Perl trying to report a suspected security |
26 | exploit attempt using an external program, /bin/mail. On Linux |
27 | platforms the /bin/mail program had an undocumented feature which |
28 | when combined with suidperl gave access to a root shell, resulting in |
29 | a serious compromise instead of reporting the exploit attempt. If you |
30 | don't have /bin/mail, or if you have 'safe setuid scripts', or if |
31 | suidperl is not installed, you are safe. |
32 | |
33 | The exploit attempt reporting feature has been completely removed from |
34 | all the Perl 5.7 releases (and will be gone also from the maintenance |
35 | release 5.6.1), so that particular vulnerability isn't there anymore. |
36 | However, further security vulnerabilities are, unfortunately, always |
37 | possible. The suidperl code is being reviewed and if deemed too risky |
38 | to continue to be supported, it may be completely removed from future |
39 | releases. In any case, suidperl should only be used by security |
40 | experts who know exactly what they are doing and why they are using |
41 | suidperl instead of some other solution such as sudo (see |
42 | http://www.courtesan.com/sudo/). |
43 | |
d468ca04 |
44 | =head1 Incompatible Changes |
45 | |
46 | =over 4 |
47 | |
48 | =item * |
49 | |
50 | Although "you shouldn't do that", it was possible to write code that |
51 | depends on Perl's hashed key order (Data::Dumper does this). The new |
52 | algorithm "One-at-a-Time" produces a different hashed key order. |
6a9b4349 |
53 | More details are in L</"Performance Enhancements">. |
54 | |
55 | =item * |
56 | |
57 | The list of filenames from glob() (or <...>) is now by default sorted |
58 | alphabetically to be csh-compliant. (bsd_glob() does still sort platform |
59 | natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.) |
d468ca04 |
60 | |
61 | =back |
62 | |
63 | =head1 Core Enhancements |
64 | |
65 | =over 4 |
66 | |
67 | =item * |
68 | |
66917b5b |
69 | AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute |
70 | to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value. |
65db4721 |
71 | |
72 | =item * |
73 | |
74 | IO is now by default done via PerlIO rather than system's "stdio". |
75 | PerlIO allows "layers" to be "pushed" onto a file handle to alter the |
76 | handle's behaviour. Layers can be specified at open time via 3-arg |
77 | form of open: |
78 | |
79 | open($fh,'>:crlf :utf8', $path) || ... |
80 | |
81 | or on already opened handles via extended C<binmode>: |
82 | |
83 | binmode($fh,':encoding(iso-8859-7)'); |
84 | |
85 | The built-in layers are: unix (low level read/write), stdio (as in |
86 | previous Perls), perlio (re-implementation of stdio buffering in a |
87 | portable manner), crlf (does CRLF <=> "\n" translation as on Win32, |
88 | but available on any platform). A mmap layer may be available if |
89 | platform supports it (mostly UNIXes). |
90 | |
91 | Layers to be applied by default may be specified via the 'open' pragma. |
92 | |
6a9b4349 |
93 | See L</"Installation and Configuration Improvements"> for the effects |
94 | of PerlIO on your architecture name. |
95 | |
65db4721 |
96 | =item * |
97 | |
98 | File handles can be marked as accepting Perl's internal encoding of Unicode |
e49a87d3 |
99 | (UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" : |
65db4721 |
100 | |
101 | open($fh,">:utf8","Uni.txt"); |
102 | |
7221edc9 |
103 | Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named |
104 | for you since it's not UTF-8 what you will be getting but instead |
105 | UTF-EBCDIC. See L<perlunicode>, L<utf8>, and |
106 | http://www.unicode.org/unicode/reports/tr16/ for more information. |
107 | In future releases this naming may change. |
66917b5b |
108 | |
65db4721 |
109 | =item * |
110 | |
111 | File handles can translate character encodings from/to Perl's internal |
112 | Unicode form on read/write via the ":encoding()" layer. |
113 | |
114 | =item * |
115 | |
116 | File handles can be opened to "in memory" files held in Perl scalars via: |
117 | |
118 | open($fh,'>', \$variable) || ... |
119 | |
120 | =item * |
121 | |
6a9b4349 |
122 | Anonymous temporary files are available without need to |
123 | 'use FileHandle' or other module via |
124 | |
125 | open($fh,"+>", undef) || ... |
126 | |
127 | That is a literal undef, not an undefined value. |
d468ca04 |
128 | |
129 | =item * |
65db4721 |
130 | |
131 | The list form of C<open> is now implemented for pipes (at least on UNIX): |
132 | |
133 | open($fh,"-|", 'cat', '/etc/motd') |
134 | |
135 | creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in |
136 | the child process. |
137 | |
138 | =item * |
6a9b4349 |
139 | |
31d2fa6a |
140 | The following builtin functions are now overridable: chop(), chomp(), |
66917b5b |
141 | each(), keys(), pop(), push(), shift(), splice(), unshift(). |
6a9b4349 |
142 | |
143 | =item * |
144 | |
145 | Formats now support zero-padded decimal fields. |
146 | |
147 | =item * |
148 | |
149 | Perl now tries internally to use integer values in numeric conversions |
150 | and basic arithmetics (+ - * /) if the arguments are integers, and |
151 | tries also to keep the results stored internally as integers. |
152 | This change leads into often slightly faster and always less lossy |
3a2c142b |
153 | arithmetics. (Previously Perl always preferred floating point numbers |
154 | in its math.) |
6a9b4349 |
155 | |
156 | =item * |
3b131e01 |
157 | |
66917b5b |
158 | The printf() and sprintf() now support parameter reordering using the |
159 | C<%\d+\$> and C<*\d+\$> syntaxes. For example |
160 | |
161 | print "%2\$s %1\$s\n", "foo", "bar"; |
162 | |
163 | will print "bar foo\n"; This feature helps in writing |
164 | internationalised software. |
d468ca04 |
165 | |
6a9b4349 |
166 | =item * |
167 | |
168 | Unicode in general should be now much more usable. Unicode can be |
169 | used in hash keys, Unicode in regular expressions should work now, |
170 | Unicode in tr/// should work now (though tr/// seems to be a |
171 | particularly tricky to get right, so you have been warned) |
172 | |
173 | =item * |
174 | |
175 | The Unicode Character Database coming with Perl has been upgraded |
66917b5b |
176 | to Unicode 3.1. For more information, see http://www.unicode.org/, |
177 | and http://www.unicode.org/unicode/reports/tr27/ |
178 | |
31d2fa6a |
179 | For developers interested in enhancing Perl's Unicode capabilities: |
66917b5b |
180 | almost all the UCD files are included with the Perl distribution in |
181 | the lib/unicode subdirectory. The most notable omission, for space |
182 | considerations, is the Unihan database. |
6a9b4349 |
183 | |
184 | =item * |
185 | |
186 | The Unicode character classes \p{Blank} and \p{SpacePerl} have been |
187 | added. "Blank" is like C isblank(), that is, it contains only |
188 | "horizontal whitespace" (the space character is, the newline isn't), |
189 | and the "SpacePerl" is the Unicode equivalent of C<\s> (\p{Space} |
190 | isn't, since that includes the vertical tabulator character, whereas |
191 | C<\s> doesn't.) |
192 | |
193 | =back |
194 | |
3b131e01 |
195 | =head1 Modules and Pragmata |
6a9b4349 |
196 | |
197 | =head2 New Modules |
198 | |
199 | =over 4 |
200 | |
201 | =item * |
202 | |
7221edc9 |
203 | B::Concise, by Stephen McCamant, is a new compiler backend for |
31d2fa6a |
204 | walking the Perl syntax tree, printing concise info about ops. |
205 | The output is highly customisable. |
206 | |
207 | See L<B::Concise> for more information. |
6a9b4349 |
208 | |
209 | =item * |
210 | |
7221edc9 |
211 | Class::ISA, by Sean Burke, for reporting the search path for a |
212 | class's ISA tree, has been added. |
6a9b4349 |
213 | |
31d2fa6a |
214 | See L<Class::ISA> for more information. |
215 | |
6a9b4349 |
216 | =item * |
217 | |
218 | Cwd has now a split personality: if possible, an extension is used, |
219 | (this will hopefully be both faster and more secure and robust) but |
220 | if not possible, the familiar Perl library implementation is used. |
221 | |
222 | =item * |
223 | |
8b40ef3a |
224 | Digest, a frontend module for calculating digests (checksums), |
6a9b4349 |
225 | from Gisle Aas, has been added. |
226 | |
31d2fa6a |
227 | See L<Digest> for more information. |
228 | |
6a9b4349 |
229 | =item * |
230 | |
7221edc9 |
231 | Digest::MD5 for calculating MD5 digests (checksums), by Gisle Aas, |
6a9b4349 |
232 | has been added. |
233 | |
3b131e01 |
234 | use Digest::MD5 'md5_hex'; |
235 | |
236 | $digest = md5_hex("Thirsty Camel"); |
237 | |
238 | print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1 |
239 | |
3a2c142b |
240 | NOTE: the MD5 backward compatibility module is deliberately not |
6a9b4349 |
241 | included since its use is discouraged. |
242 | |
31d2fa6a |
243 | See L<Digest::MD5> for more information. |
244 | |
6a9b4349 |
245 | =item * |
246 | |
7221edc9 |
247 | Encode, by Nick Ing-Simmons, provides a mechanism to translate |
31d2fa6a |
248 | between different character encodings. Support for Unicode, |
249 | ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are |
250 | compiled in to the module. Several other encodings (like Japanese, |
251 | Chinese, and MacIntosh encodings) are included and will be loaded at |
252 | runtime. |
6a9b4349 |
253 | |
254 | Any encoding supported by Encode module is also available to the |
255 | ":encoding()" layer if PerlIO is used. |
256 | |
31d2fa6a |
257 | See L<Encode> for more information. |
258 | |
6a9b4349 |
259 | =item * |
260 | |
8b40ef3a |
261 | Filter::Simple is an easy-to-use frontend to Filter::Util::Call, |
6a9b4349 |
262 | from Damian Conway. |
263 | |
3b131e01 |
264 | # in MyFilter.pm: |
265 | |
266 | package MyFilter; |
267 | |
268 | use Filter::Simple sub { |
269 | while (my ($from, $to) = splice @_, 0, 2) { |
270 | s/$from/$to/g; |
271 | } |
272 | }; |
273 | |
274 | 1; |
275 | |
276 | # in user's code: |
277 | |
278 | use MyFilter qr/red/ => 'green'; |
279 | |
280 | print "red\n"; # this code is filtered, will print "green\n" |
281 | print "bored\n"; # this code is filtered, will print "bogreen\n" |
282 | |
283 | no MyFilter; |
284 | |
285 | print "red\n"; # this code is not filtered, will print "red\n" |
286 | |
31d2fa6a |
287 | See L<Filter::Simple> for more information. |
288 | |
6a9b4349 |
289 | =item * |
290 | |
7221edc9 |
291 | Filter::Util::Call, by Paul Marquess, provides you with the |
6a9b4349 |
292 | framework to write I<Source Filters> in Perl. For most uses |
8b40ef3a |
293 | the frontend Filter::Simple is to be preferred. |
31d2fa6a |
294 | See L<Filter::Util::Call> for more information. |
6a9b4349 |
295 | |
296 | =item * |
297 | |
298 | Locale::Constants, Locale::Country, Locale::Currency, and Locale::Language, |
299 | from Neil Bowers, have been added. They provide the codes for various |
300 | locale standards, such as "fr" for France, "usd" for US Dollar, and |
301 | "jp" for Japanese. |
302 | |
3b131e01 |
303 | use Locale::Country; |
31d2fa6a |
304 | |
3b131e01 |
305 | $country = code2country('jp'); # $country gets 'Japan' |
306 | $code = country2code('Norway'); # $code gets 'no' |
307 | |
31d2fa6a |
308 | See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>, |
309 | and L<Locale::Language> for more information. |
310 | |
6a9b4349 |
311 | =item * |
312 | |
7221edc9 |
313 | MIME::Base64, by Gisle Aas, allows you to encode data in base64. |
6a9b4349 |
314 | |
3b131e01 |
315 | use MIME::Base64; |
316 | |
317 | $encoded = encode_base64('Aladdin:open sesame'); |
318 | $decoded = decode_base64($encoded); |
319 | |
320 | print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ==" |
321 | |
31d2fa6a |
322 | See L<MIME::Base64> for more information. |
323 | |
6a9b4349 |
324 | =item * |
325 | |
7221edc9 |
326 | MIME::QuotedPrint, by Gisle Aas, allows you to encode data in |
6a9b4349 |
327 | quoted-printable encoding. |
328 | |
3b131e01 |
329 | use MIME::QuotedPrint; |
330 | |
331 | $encoded = encode_qp("Smiley in Unicode: \x{263a}"); |
332 | $decoded = decode_qp($encoded); |
333 | |
334 | print $encoded, "\n"; # "Smiley in Unicode: =263A" |
335 | |
6a9b4349 |
336 | MIME::QuotedPrint has been enhanced to provide the basic methods |
337 | necessary to use it with PerlIO::Via as in : |
338 | |
3b131e01 |
339 | use MIME::QuotedPrint; |
340 | open($fh,">Via(MIME::QuotedPrint)",$path) |
6a9b4349 |
341 | |
31d2fa6a |
342 | See L<MIME::QuotedPrint> for more information. |
343 | |
6a9b4349 |
344 | =item * |
345 | |
7221edc9 |
346 | PerlIO::Scalar, by Nick Ing-Simmons, provides the implementation of |
31d2fa6a |
347 | IO to "in memory" Perl scalars as discussed above. It also serves as |
348 | an example of a loadable layer. Other future possibilities include |
349 | PerlIO::Array and PerlIO::Code. See L<PerlIO::Scalar> for more |
350 | information. |
6a9b4349 |
351 | |
352 | =item * |
353 | |
7221edc9 |
354 | PerlIO::Via, by Nick Ing-Simmons, acts as a PerlIO layer and wraps |
31d2fa6a |
355 | PerlIO layer functionality provided by a class (typically implemented |
356 | in perl code). |
6a9b4349 |
357 | |
3b131e01 |
358 | use MIME::QuotedPrint; |
359 | open($fh,">Via(MIME::QuotedPrint)",$path) |
360 | |
361 | This will automatically convert everything output to C<$fh> |
31d2fa6a |
362 | to Quoted-Printable. See L<PerlIO::Via> for more information. |
3b131e01 |
363 | |
6a9b4349 |
364 | =item * |
365 | |
7221edc9 |
366 | Pod::Text::Overstrike, by Joe Smith, has been added. |
6a9b4349 |
367 | It converts POD data to formatted overstrike text. |
31d2fa6a |
368 | See L<Pod::Text::Overstrike> for more information. |
6a9b4349 |
369 | |
370 | =item * |
371 | |
66917b5b |
372 | Switch from Damian Conway has been added. Just by saying |
6a9b4349 |
373 | |
66917b5b |
374 | use Switch; |
6a9b4349 |
375 | |
66917b5b |
376 | you have C<switch> and C<case> available in Perl. |
6a9b4349 |
377 | |
3b131e01 |
378 | use Switch; |
379 | |
380 | switch ($val) { |
381 | |
382 | case 1 { print "number 1" } |
383 | case "a" { print "string a" } |
384 | case [1..10,42] { print "number in list" } |
385 | case (@array) { print "number in list" } |
386 | case /\w+/ { print "pattern" } |
387 | case qr/\w+/ { print "pattern" } |
388 | case (%hash) { print "entry in hash" } |
389 | case (\%hash) { print "entry in hash" } |
390 | case (\&sub) { print "arg to subroutine" } |
391 | else { print "previous case not true" } |
392 | } |
393 | |
31d2fa6a |
394 | See L<Switch> for more information. |
395 | |
6a9b4349 |
396 | =item * |
397 | |
398 | Text::Balanced from Damian Conway has been added, for |
399 | extracting delimited text sequences from strings. |
400 | |
3b131e01 |
401 | use Text::Balanced 'extract_delimited'; |
31d2fa6a |
402 | |
3b131e01 |
403 | ($a, $b) = extract_delimited("'never say never', he never said", "'", ''); |
404 | |
7221edc9 |
405 | $a will be "'never say never'", $b will be ', he never said'. |
3b131e01 |
406 | |
407 | In addition to extract_delimited() there are also extract_bracketed(), |
408 | extract_quotelike(), extract_codeblock(), extract_variable(), |
409 | extract_tagged(), extract_multiple(), gen_delimited_pat(), and |
7221edc9 |
410 | gen_extract_tagged(). With these you can implement rather advanced |
411 | parsing algorithms. See L<Text::Balanced> for more information. |
3b131e01 |
412 | |
6a9b4349 |
413 | =item * |
414 | |
7221edc9 |
415 | Tie::RefHash::Nestable, by Edward Avis, allows storing hash references |
31d2fa6a |
416 | (unlike the standard Tie::Refhash) The module is contained within |
417 | Tie::RefHash. |
6a9b4349 |
418 | |
419 | =item * |
420 | |
7221edc9 |
421 | XS::Typemap, by Tim Jenness, is a test extension that exercises XS |
422 | typemaps. Nothing gets installed but for extension writers the code |
423 | is worth studying. |
6a9b4349 |
424 | |
425 | =back |
426 | |
427 | =head2 Updated And Improved Modules and Pragmata |
428 | |
429 | =over 4 |
430 | |
431 | =item * |
432 | |
3b131e01 |
433 | B::Deparse should be now more robust. It still far from providing a full |
31d2fa6a |
434 | round trip for any random piece of Perl code, though, and is under active |
3b131e01 |
435 | development: expect more robustness in 5.7.2. |
6a9b4349 |
436 | |
437 | =item * |
438 | |
3b131e01 |
439 | Class::Struct can now define the classes in compile time. |
6a9b4349 |
440 | |
441 | =item * |
442 | |
31d2fa6a |
443 | Math::BigFloat has undergone much fixing, and in addition the fmod() |
444 | function now supports modulus operations. |
3b131e01 |
445 | |
446 | (The fixed Math::BigFloat module is also available in CPAN for those |
447 | who can't upgrade their Perl: http://www.cpan.org/authors/id/J/JP/JPEACOCK/) |
6a9b4349 |
448 | |
449 | =item * |
450 | |
451 | Devel::Peek now has an interface for the Perl memory statistics |
452 | (this works only if you are using perl's malloc, and if you have |
453 | compiled with debugging). |
454 | |
455 | =item * |
456 | |
457 | IO::Socket has now atmark() method, which returns true if the socket |
458 | is positioned at the out-of-band mark. The method is also exportable |
459 | as a sockatmark() function. |
460 | |
3b131e01 |
461 | =item * |
6a9b4349 |
462 | |
463 | IO::Socket::INET has support for ReusePort option (if your platform |
3b131e01 |
464 | supports it). The Reuse option now has an alias, ReuseAddr. For clarity |
465 | you may want to prefer ReuseAddr. |
6a9b4349 |
466 | |
467 | =item * |
468 | |
3b131e01 |
469 | Net::Ping has been enhanced. There is now "external" protocol which |
470 | uses Net::Ping::External module which runs external ping(1) and parses |
471 | the output. An alpha version of Net::Ping::External is available in |
472 | CPAN and in 5.7.2 the Net::Ping::External may be integrated to Perl. |
6a9b4349 |
473 | |
474 | =item * |
475 | |
476 | The C<open> pragma allows layers other than ":raw" and ":crlf" when |
477 | using PerlIO. |
478 | |
479 | =item * |
480 | |
481 | POSIX::sigaction() is now much more flexible and robust. |
3b131e01 |
482 | You can now install coderef handlers, 'DEFAULT', and 'IGNORE' |
483 | handlers, installing new handlers was not atomic. |
6a9b4349 |
484 | |
485 | =item * |
486 | |
487 | The Test module has been significantly enhanced. Its use is |
488 | greatly recommended for module writers. |
489 | |
490 | =item * |
491 | |
492 | The utf8:: name space (as in the pragma) provides various |
493 | Perl-callable functions to provide low level access to Perl's |
494 | internal Unicode representation. At the moment only length() |
495 | has been implemented. |
496 | |
d468ca04 |
497 | =back |
498 | |
66917b5b |
499 | The following modules have been upgraded from the versions at CPAN: |
7221edc9 |
500 | CPAN, CGI, DB_File, File::Temp, Getopt::Long, Pod::Man, Pod::Text, |
3b131e01 |
501 | Storable, Text-Tabs+Wrap. |
6a9b4349 |
502 | |
d468ca04 |
503 | =head1 Performance Enhancements |
504 | |
505 | =over 4 |
506 | |
507 | =item * |
508 | |
509 | Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm |
7221edc9 |
510 | (http://burtleburtle.net/bob/hash/doobs.html). This algorithm is |
511 | reasonably fast while producing a much better spread of values than |
512 | the old hashing algorithm (originally by Chris Torek, later tweaked by |
513 | Ilya Zakharevich). Hash values output from the algorithm on a hash of |
514 | all 3-char printable ASCII keys comes much closer to passing the |
515 | DIEHARD random number generation tests. According to perlbench, this |
516 | change has not affected the overall speed of Perl. |
d468ca04 |
517 | |
6a9b4349 |
518 | =item * |
519 | |
520 | unshift() should now be noticeably faster. |
521 | |
d468ca04 |
522 | =back |
523 | |
6a9b4349 |
524 | =head1 Utility Changes |
525 | |
526 | =over 4 |
527 | |
528 | =item * |
529 | |
530 | h2xs now produces template README. |
531 | |
532 | =item * |
533 | |
534 | s2p has been completely rewritten in Perl. (It is in fact a full |
535 | implementation of sed in Perl.) |
536 | |
537 | =item * |
538 | |
539 | xsubpp now supports OUT keyword. |
540 | |
541 | =back |
542 | |
543 | =head1 New Documentation |
544 | |
545 | =head2 perlclib |
546 | |
547 | Internal replacements for standard C library functions. |
66917b5b |
548 | (Interesting only for extension writers and Perl core hackers.) |
6a9b4349 |
549 | |
550 | =head2 perliol |
551 | |
552 | Internals of PerlIO with layers. |
553 | |
554 | =head2 README.aix |
555 | |
556 | Documentation on compiling Perl on AIX has been added. AIX has |
e49a87d3 |
557 | several different C compilers and getting the right patch level |
6a9b4349 |
558 | is essential. On install README.aix will be installed as L<perlaix>. |
559 | |
560 | =head2 README.bs2000 |
561 | |
e49a87d3 |
562 | Documentation on compiling Perl on the POSIX-BC platform (an EBCDIC |
6a9b4349 |
563 | mainframe environment) has been added. |
564 | |
565 | This was formerly known as README.posix-bc but the name was considered |
566 | to be too confusing (it has nothing to do with the POSIX module or the |
567 | POSIX standard). On install README.bs2000 will be installed as L<perlbs2000>. |
568 | |
569 | =head2 README.macos |
570 | |
571 | In perl 5.7.1 (and in the 5.6.1) the MacPerl sources have been |
8b40ef3a |
572 | synchronised with the standard Perl sources. To compile MacPerl |
6a9b4349 |
573 | some additional steps are required, and this file documents those |
574 | steps. On install README.macos will be installed as L<perlmacos>. |
575 | |
576 | =head2 README.mpeix |
577 | |
578 | The README.mpeix has been podified, which means that this information |
579 | about compiling and using Perl on the MPE/iX miniframe platform will |
66917b5b |
580 | be installed as L<perlmpeix>. |
6a9b4349 |
581 | |
582 | =head2 README.solaris |
583 | |
584 | README.solaris has been created and Solaris wisdom from elsewhere |
585 | in the Perl documentation has been collected there. On install |
586 | README.solaris will be installed as L<perlsolaris>. |
587 | |
588 | =head2 README.vos |
589 | |
590 | The README.vos has been podified, which means that this information |
66917b5b |
591 | about compiling and using Perl on the Stratus VOS miniframe platform |
592 | will be installed as L<perlvos>. |
6a9b4349 |
593 | |
594 | =head2 Porting/repository.pod |
595 | |
596 | Documentation on how to use the Perl source repository has been added. |
597 | |
d468ca04 |
598 | =head1 Installation and Configuration Improvements |
599 | |
66917b5b |
600 | =over 4 |
601 | |
602 | =item * |
603 | |
6a9b4349 |
604 | Because PerlIO is now the default on most platforms, "-perlio" doesn't |
605 | get appended to the $Config{archname} (also known as $^O) anymore. |
606 | Instead, if you explicitly choose not to use perlio (Configure command |
607 | line option -Uuseperlio), you will get "-stdio" appended. |
608 | |
66917b5b |
609 | =item * |
610 | |
6a9b4349 |
611 | Another change related to the architecture name is that "-64all" |
3b131e01 |
612 | (-Duse64bitall, or "maximally 64-bit") is appended only if your |
613 | pointers are 64 bits wide. (To be exact, the use64bitall is ignored.) |
6a9b4349 |
614 | |
66917b5b |
615 | =item * |
616 | |
6a9b4349 |
617 | APPLLIB_EXP, a less-know configuration-time definition, has been |
618 | documented. It can be used to prepend site-specific directories |
619 | to Perl's default search path (@INC), see INSTALL for information. |
620 | |
66917b5b |
621 | =item * |
622 | |
6a9b4349 |
623 | Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM |
624 | has been documented in INSTALL. |
625 | |
66917b5b |
626 | =item * |
627 | |
6a9b4349 |
628 | If you are on IRIX or Tru64 platforms, new profiling/debugging options |
3b131e01 |
629 | have been added, see L<perlhack> for more information about pixie and |
6a9b4349 |
630 | Third Degree. |
631 | |
66917b5b |
632 | =back |
633 | |
6a9b4349 |
634 | =head2 New Or Improved Platforms |
635 | |
66917b5b |
636 | For the list of platforms known to support Perl, |
637 | see L<perlport/"Supported Platforms">. |
638 | |
6a9b4349 |
639 | =over 4 |
640 | |
641 | =item * |
642 | |
643 | AIX dynamic loading should be now better supported. |
644 | |
645 | =item * |
646 | |
66917b5b |
647 | After a long pause, AmigaOS has been verified to be happy with Perl. |
648 | |
649 | =item * |
650 | |
651 | EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA) |
652 | have been regained. Many test suite tests still fail and the |
653 | co-existence of Unicode and EBCDIC isn't quite settled, but the |
654 | situation is much better than with Perl 5.6. See L<perlos390>, |
655 | L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information. |
656 | |
657 | =item * |
658 | |
7221edc9 |
659 | Building perl with -Duseithreads or -Duse5005threads now works under |
660 | HP-UX 10.20 (previously it only worked under 10.30 or later). You will |
661 | need a thread library package installed. See README.hpux. |
6a9b4349 |
662 | |
663 | =item * |
664 | |
665 | MacOS Classic (MacPerl has of course been available since |
666 | perl 5.004 but now the source code bases of standard Perl |
8b40ef3a |
667 | and MacPerl have been synchronised) |
6a9b4349 |
668 | |
669 | =item * |
670 | |
31d2fa6a |
671 | NCR MP-RAS is now supported. |
6a9b4349 |
672 | |
673 | =item * |
674 | |
31d2fa6a |
675 | NonStop-UX is now supported. |
6a9b4349 |
676 | |
677 | =item * |
678 | |
31d2fa6a |
679 | Amdahl UTS is now supported. |
6a9b4349 |
680 | |
681 | =item * |
682 | |
683 | z/OS (formerly known as OS/390, formerly known as MVS OE) has now |
684 | support for dynamic loading. This is not selected by default, |
685 | however, you must specify -Dusedl in the arguments of Configure. |
686 | |
687 | =back |
688 | |
689 | =head2 Generic Improvements |
690 | |
d468ca04 |
691 | =over 4 |
692 | |
693 | =item * |
694 | |
695 | Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm) |
6a9b4349 |
696 | when building the Perl binary. The only exception to this is SunOS 4.x, |
d468ca04 |
697 | which needs them. |
698 | |
6a9b4349 |
699 | =item * |
700 | |
8b40ef3a |
701 | Some new Configure symbols, useful for extension writers: |
702 | |
703 | =over 8 |
704 | |
705 | =item d_cmsghdr |
706 | |
707 | For struct cmsghdr. |
708 | |
709 | =item d_fcntl_can_lock |
710 | |
711 | Whether fcntl() can be used for file locking. |
712 | |
713 | =item d_fsync |
714 | |
715 | =item d_getitimer |
716 | |
717 | =item d_getpagsz |
718 | |
719 | For getpagesize(), though you should prefer POSIX::sysconf(_SC_PAGE_SIZE)) |
720 | |
721 | =item d_msghdr_s |
722 | |
723 | For struct msghdr. |
724 | |
725 | =item need_va_copy |
726 | |
727 | Whether one needs to use Perl_va_copy() to copy varargs. |
728 | |
729 | =item d_readv |
730 | |
731 | =item d_recvmsg |
732 | |
733 | =item d_sendmsg |
734 | |
735 | =item sig_size |
736 | |
737 | The number of elements in an array needed to hold all the available signals. |
738 | |
739 | =item d_sockatmark |
740 | |
741 | =item d_strtoq |
742 | |
743 | =item d_u32align |
744 | |
745 | Whether one needs to access character data aligned by U32 sized pointers. |
746 | |
747 | =item d_ualarm |
748 | |
749 | =item d_usleep |
750 | |
751 | =back |
6a9b4349 |
752 | |
753 | =item * |
754 | |
755 | Removed Configure symbols: the PDP-11 memory model settings: huge, |
756 | large, medium, models. |
757 | |
758 | =item * |
759 | |
760 | SOCKS support is now much more robust. |
761 | |
762 | =item * |
763 | |
764 | If your file system supports symbolic links you can build Perl outside |
765 | of the source directory by |
3b131e01 |
766 | |
6a9b4349 |
767 | mkdir /tmp/perl/build/directory |
768 | cd /tmp/perl/build/directory |
769 | sh /path/to/perl/source/Configure -Dmksymlinks ... |
770 | |
771 | This will create in /tmp/perl/build/directory a tree of symbolic links |
772 | pointing to files in /path/to/perl/source. The original files are left |
773 | unaffected. After Configure has finished you can just say |
774 | |
775 | make all test |
776 | |
777 | and Perl will be built and tested, all in /tmp/perl/build/directory. |
778 | |
d468ca04 |
779 | =back |
780 | |
781 | =head1 Selected Bug Fixes |
782 | |
7221edc9 |
783 | Numerous memory leaks and uninitialized memory accesses have been hunted down. |
31d2fa6a |
784 | Most importantly anonymous subs used to leak quite a bit. |
6a9b4349 |
785 | |
d468ca04 |
786 | =over 4 |
787 | |
788 | =item * |
789 | |
7221edc9 |
790 | chop(@list) in list context returned the characters chopped in |
791 | reverse order. This has been reversed to be in the right order. |
31d2fa6a |
792 | |
793 | =item * |
794 | |
3a2c142b |
795 | The order of DESTROYs has been made more predictable. |
6a9b4349 |
796 | |
797 | =item * |
798 | |
799 | mkdir() now ignores trailing slashes in the directory name, |
800 | as mandated by POSIX. |
801 | |
802 | =item * |
803 | |
66917b5b |
804 | Attributes (like :shared) didn't work with our(). |
805 | |
806 | =item * |
807 | |
808 | The PERL5OPT environment variable (for passing command line arguments |
809 | to Perl) didn't work for more than a single group of options. |
6a9b4349 |
810 | |
811 | =item * |
812 | |
31d2fa6a |
813 | The tainting behaviour of sprintf() has been rationalized. It does |
814 | not taint the result of floating point formats anymore, making the |
815 | behaviour consistent with that of string interpolation. |
816 | |
817 | =item * |
818 | |
6a9b4349 |
819 | All but the first argument of the IO syswrite() method are now optional. |
820 | |
821 | =item * |
822 | |
823 | Tie::ARRAY SPLICE method was broken. |
824 | |
825 | =item * |
826 | |
d468ca04 |
827 | vec() now tries to work with characters <= 255 when possible, but it leaves |
828 | higher character values in place. In that case, if vec() was used to modify |
829 | the string, it is no longer considered to be utf8-encoded. |
830 | |
831 | =back |
832 | |
6a9b4349 |
833 | =head2 Platform Specific Changes and Fixes |
65db4721 |
834 | |
835 | =over 4 |
836 | |
837 | =item * |
838 | |
6a9b4349 |
839 | Linux previously had problems related to sockaddrlen when using |
840 | accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname(). |
65db4721 |
841 | |
842 | =item * |
843 | |
66917b5b |
844 | Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O. |
65db4721 |
845 | |
31d2fa6a |
846 | =item * |
847 | |
848 | Windows |
849 | |
850 | =over 8 |
851 | |
852 | =item * |
853 | |
854 | Borland C++ v5.5 is now a supported compiler that can build Perl. |
855 | However, the generated binaries continue to be incompatible with those |
856 | generated by the other supported compilers (GCC and Visual C++). |
857 | |
858 | =item * |
859 | |
860 | Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root. |
861 | Other bugs in chdir() and Cwd::cwd() have also been fixed. |
862 | |
863 | =item * |
864 | |
865 | Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x. |
866 | |
867 | =item * |
868 | |
7221edc9 |
869 | HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html |
870 | |
871 | =item * |
872 | |
31d2fa6a |
873 | The makefiles now provide a single switch to bulk-enable all the features |
874 | enabled in ActiveState ActivePerl (a popular binary distribution). |
875 | |
876 | =back |
877 | |
6a9b4349 |
878 | =back |
65db4721 |
879 | |
6a9b4349 |
880 | =head1 New or Changed Diagnostics |
65db4721 |
881 | |
6a9b4349 |
882 | Two new debugging options have been added: if you have compiled your |
883 | Perl with debugging, you can use the -DT and -DR options to trace |
8b40ef3a |
884 | tokenising and to add reference counts to displaying variables, |
6a9b4349 |
885 | respectively. |
65db4721 |
886 | |
6a9b4349 |
887 | =over 4 |
65db4721 |
888 | |
889 | =item * |
890 | |
7221edc9 |
891 | If an attempt to use a (non-blessed) reference as an array index |
6a9b4349 |
892 | is made, a warning is given. |
65db4721 |
893 | |
6a9b4349 |
894 | =item * |
895 | |
896 | C<push @a;> and C<unshift @a;> (with no values to push or unshift) |
897 | now give a warning. This may be a problem for generated and evaled |
898 | code. |
65db4721 |
899 | |
900 | =back |
901 | |
6a9b4349 |
902 | =head1 Changed Internals |
65db4721 |
903 | |
904 | =over 4 |
905 | |
906 | =item * |
907 | |
66917b5b |
908 | Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv(). |
909 | For the full list of the available APIs see L<perlapi>. |
65db4721 |
910 | |
911 | =item * |
912 | |
66917b5b |
913 | dTHR and djSP have been obsoleted; the former removed (because it's |
914 | a no-op) and the latter replaced with dSP. |
6a9b4349 |
915 | |
916 | =item * |
917 | |
3a2c142b |
918 | Perl now uses system malloc instead of Perl malloc on all 64-bit |
31d2fa6a |
919 | platforms, and even in some not-always-64-bit platforms like AIX, |
920 | IRIX, and Solaris. This change breaks backward compatibility but |
921 | Perl's malloc has problems with large address spaces and also the |
922 | speed of vendors' malloc is generally better in large address space |
923 | machines (Perl's malloc is mostly tuned for space). |
65db4721 |
924 | |
925 | =back |
926 | |
b1085720 |
927 | =head1 New Tests |
928 | |
929 | Many new tests have been added. The most notable is probably the |
930 | lib/1_compile: it is very notable because running it takes quite a |
931 | long time -- it test compiles all the Perl modules in the distribution. |
932 | Please be patient. |
933 | |
d468ca04 |
934 | =head1 Known Problems |
935 | |
7221edc9 |
936 | Note that unlike other sections in this document (which describe |
937 | changes since 5.7.0) this section is cumulative containing known |
938 | problems for all the 5.7 releases. |
31d2fa6a |
939 | |
7221edc9 |
940 | =head2 AIX vac 5.0.0.0 May Produce Buggy Code For Perl |
6a9b4349 |
941 | |
7221edc9 |
942 | The AIX C compiler vac version 5.0.0.0 may produce buggy code, |
943 | resulting in few random tests failing, but when the failing tests |
944 | are run by hand, they succeed. We suggest upgrading to at least |
945 | vac version 5.0.1.0, that has been known to compile Perl correctly. |
946 | "lslpp -L|grep vac.C" will tell you the vac version. |
6a9b4349 |
947 | |
7221edc9 |
948 | =head2 lib/ftmp-security tests warn 'system possibly insecure' |
6a9b4349 |
949 | |
7221edc9 |
950 | Don't panic. Read INSTALL 'make test' section instead. |
6a9b4349 |
951 | |
7221edc9 |
952 | =head2 lib/io_multihomed Fails In LP64-Configured HP-UX |
6a9b4349 |
953 | |
7221edc9 |
954 | The lib/io_multihomed test may hang in HP-UX if Perl has been |
955 | configured to be 64-bit. Because other 64-bit platforms do not hang in |
956 | this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The |
957 | test attempts to create and connect to "multihomed" sockets (sockets |
958 | which have multiple IP addresses). |
6a9b4349 |
959 | |
7221edc9 |
960 | =head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX |
961 | |
962 | If perl is configured with -Duse64bitall, the successful result of the |
963 | subtest 10 of lib/posix may arrive before the successful result of the |
964 | subtest 9, which confuses the test harness so much that it thinks the |
965 | subtest 9 failed. |
966 | |
967 | =head2 lib/b test 19 |
968 | |
3a2c142b |
969 | The test fails on various platforms (PA64 and IA64 are known), but the |
7221edc9 |
970 | exact cause is still being investigated. |
971 | |
972 | =head2 Linux With Sfio Fails op/misc Test 48 |
973 | |
974 | No known fix. |
6a9b4349 |
975 | |
976 | =head2 sigaction test 13 in VMS |
977 | |
3a2c142b |
978 | The test is known to fail; whether it's because of VMS of because |
979 | of faulty test is not known. |
6a9b4349 |
980 | |
d468ca04 |
981 | =head2 sprintf tests 129 and 130 |
982 | |
3a2c142b |
983 | The op/sprintf tests 129 and 130 are known to fail on some platforms. |
7221edc9 |
984 | Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX. |
d468ca04 |
985 | The failing platforms do not comply with the ANSI C Standard, line |
986 | 19ff on page 134 of ANSI X3.159 1989 to be exact. (They produce |
987 | something else than "1" and "-1" when formatting 0.6 and -0.6 using |
988 | the printf format "%.0f", most often they produce "0" and "-0".) |
989 | |
7221edc9 |
990 | =head2 Failure of Thread tests |
991 | |
992 | The subtests 19 and 20 of lib/thr5005.t test are known to fail due to |
993 | fundamental problems in the 5.005 threading implementation. These are |
994 | not new failures--Perl 5.005_0x has the same bugs, but didn't have |
995 | these tests. (Note that support for 5.005-style threading remains |
996 | experimental.) |
997 | |
998 | =head2 Localising a Tied Variable Leaks Memory |
999 | |
1000 | use Tie::Hash; |
1001 | tie my %tie_hash => 'Tie::StdHash'; |
1002 | |
1003 | ... |
1004 | |
1005 | local($tie_hash{Foo}) = 1; # leaks |
1006 | |
1007 | Code like the above is known to leak memory every time the local() |
1008 | is executed. |
1009 | |
6a9b4349 |
1010 | =head2 Self-tying of Arrays and Hashes Is Forbidden |
1011 | |
1012 | Self-tying of arrays and hashes is broken in rather deep and |
1013 | hard-to-fix ways. As a stop-gap measure to avoid people from getting |
1014 | frustrated at the mysterious results (core dumps, most often) it is |
1015 | for now forbidden (you will get a fatal error even from an attempt). |
1016 | |
7221edc9 |
1017 | =head2 Building Extensions Can Fail Because Of Largefiles |
1018 | |
1019 | Some extensions like mod_perl are known to have issues with |
1020 | `largefiles', a change brought by Perl 5.6.0 in which file offsets |
1021 | default to 64 bits wide, where supported. Modules may fail to compile |
1022 | at all or compile and work incorrectly. Currently there is no good |
1023 | solution for the problem, but Configure now provides appropriate |
1024 | non-largefile ccflags, ldflags, libswanted, and libs in the %Config |
1025 | hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are |
1026 | having problems can try configuring themselves without the |
1027 | largefileness. This is admittedly not a clean solution, and the |
1028 | solution may not even work at all. One potential failure is whether |
1029 | one can (or, if one can, whether it's a good idea) link together at |
1030 | all binaries with different ideas about file offsets, all this is |
1031 | platform-dependent. |
1032 | |
1033 | =head2 The Compiler Suite Is Still Experimental |
1034 | |
1035 | The compiler suite is slowly getting better but is nowhere near |
1036 | working order yet. |
1037 | |
d468ca04 |
1038 | =head1 Reporting Bugs |
1039 | |
1040 | If you find what you think is a bug, you might check the articles |
1041 | recently posted to the comp.lang.perl.misc newsgroup and the perl |
1042 | bug database at http://bugs.perl.org. There may also be |
1043 | information at http://www.perl.com/perl/, the Perl Home Page. |
1044 | |
1045 | If you believe you have an unreported bug, please run the B<perlbug> |
1046 | program included with your release. Be sure to trim your bug down |
1047 | to a tiny but sufficient test case. Your bug report, along with the |
1048 | output of C<perl -V>, will be sent off to perlbug@perl.org to be |
8b40ef3a |
1049 | analysed by the Perl porting team. |
d468ca04 |
1050 | |
1051 | =head1 SEE ALSO |
1052 | |
1053 | The F<Changes> file for exhaustive details on what changed. |
1054 | |
1055 | The F<INSTALL> file for how to build Perl. |
1056 | |
1057 | The F<README> file for general stuff. |
1058 | |
1059 | The F<Artistic> and F<Copying> files for copyright information. |
1060 | |
1061 | =head1 HISTORY |
1062 | |
1063 | Written by Jarkko Hietaniemi <F<jhi@iki.fi>>, with many contributions |
1064 | from The Perl Porters and Perl Users submitting feedback and patches. |
1065 | |
1066 | Send omissions or corrections to <F<perlbug@perl.org>>. |
1067 | |
1068 | =cut |