-M=head1 NAME
+=head1 NAME
perldelta - what is new for perl v5.8.0
=head1 DESCRIPTION
-This document describes differences between the 5.6.0 release and the
-5.8.0 release.
+This document describes differences between the 5.6.0 release
+and the 5.8.0 release.
+
+Many of the bug fixes in 5.8.0 were already seen in the 5.6.1
+maintenance release since the two releases were kept closely
+coordinated.
+
+If you are upgrading from Perl 5.005_03, you might also want
+to read L<perl56delta>.
+
+=head1 Highlights In 5.8.0
+
+=over 4
+
+=item *
+
+Better Unicode support
+
+=item *
+
+New Thread Implementation
+
+=item *
+
+Many New Modules
+
+=item *
+
+Better Numeric Accuracy
+
+=item *
+
+Safe Signals
+
+=item *
+
+More Extensive Regression Testing
+
+=back
=head1 Incompatible Changes
=head2 64-bit platforms and malloc
-If your pointers are 64 bits wide, the Perl malloc is no more being
-used because it simply does not work with 8-byte pointers. Also,
+If your pointers are 64 bits wide, the Perl malloc is no longer being
+used because it does not work well with 8-byte pointers. Also,
usually the system mallocs on such platforms are much better optimized
-for such large memory models than the Perl malloc. Such platforms
-include 64-bit Alpha, MIPS, HPPA, PPC, and Sparc.
+for such large memory models than the Perl malloc. Some memory-hungry
+Perl applications like the PDL don't work well with Perl's malloc.
+Finally, other applications than Perl (like modperl) tend to prefer
+the system malloc. Such platforms include Alpha and 64-bit HPPA,
+MIPS, PPC, and Sparc.
=head2 AIX Dynaloading
modules. The change was made to make Perl more compliant with other
applications like modperl which are using the AIX native interface.
+=head2 Attributes for C<my> variables now handled at run-time.
+
+The C<my EXPR : ATTRS> syntax now applies variable attributes at
+run-time. (Subroutine and C<our> variables still get attributes applied
+at compile-time.) See L<attributes> for additional details. In particular,
+however, this allows variable attributes to be useful for C<tie> interfaces,
+which was a deficiency of earlier releases. Note that the new semantics
+doesn't work with the Attribute::Handlers module (as of version 0.76).
+
=head2 Socket Extension Dynamic in VMS
The Socket extension is now dynamically loaded instead of being
TCP/IP stacks of VMS: we do not know since we weren't able to test
Perl in such configurations.
+=head2 IEEE-format Floating Point Default on OpenVMS Alpha
+
+Perl now uses IEEE format (T_FLOAT) as the default internal floating
+point format on OpenVMS Alpha, potentially breaking binary compatibility
+with external libraries or existing data. G_FLOAT is still available as
+a configuration option. The default on VAX (D_FLOAT) has not changed.
+
=head2 Different Definition of the Unicode Character Classes \p{In...}
As suggested by the Unicode consortium, the Unicode character classes
Markov chain input and the few found crashes and lockups have been
fixed.
-=head2 Deprecations
-
-The current user-visible implementation of pseudo-hashes (the weird
-use of the first array element) is deprecated starting from Perl 5.8.0
-and will be removed in Perl 5.10.0, and the feature will be
-implemented differently. Not only is the current interface rather
-ugly, but the current implementation slows down normal array and hash
-use quite noticeably. The C<fields> pragma interface will remain
-available.
-
-The syntaxes C<@a->[...]> and C<@h->{...}> have now been deprecated.
+=head2 REF(...) Instead Of SCALAR(...)
-After years of trying the suidperl is considered to be too complex to
-ever be considered truly secure. The suidperl functionality is likely
-to be removed in a future release.
+A reference to a reference now stringifies as "REF(0x81485ec)" instead
+of "SCALAR(0x81485ec)" in order to be more consistent with the return
+value of ref().
-The C<package;> syntax (C<package> without an argument has been
-deprecated. Its semantics were never that clear and its
-implementation even less so. If you have used that feature to
-disallow all but fully qualified variables, C<use strict;> instead.
+=head2 Deprecations
=over 4
=item *
-A reference to a reference now stringify as "REF(0x81485ec)" instead
-of "SCALAR(0x81485ec)" in order to be more consistent with the return
-value of ref().
+The obsolete chat2 library that should never have been allowed
+to escape the laboratory has been decommissioned.
=item *
=item *
-The obsolete chat2 library that should never have been allowed
-to escape the laboratory has been decommissioned.
+The (bogus) escape sequences \8 and \9 now give an optional warning
+("Unrecognized escape passed through"). There is no need to \-escape
+any C<\w> character.
=item *
-The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
-recognised but now cause fatal errors. The previous behaviour of
-ignoring them by default and warning if requested was unacceptable
-since it, in a way, falsely promised that the features could be used.
+The list of filenames from glob() (or <...>) is now by default sorted
+alphabetically to be csh-compliant (which is what happened before
+in most UNIX platforms). (bsd_glob() does still sort platform
+natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
=item *
-The (bogus) escape sequences \8 and \9 now give an optional warning
-("Unrecognized escape passed through"). There is no need to \-escape
-any C<\w> character.
+Spurious syntax errors generated in certain situations, when glob()
+caused File::Glob to be loaded for the first time, have been fixed.
+
+=item *
+
+Although "you shouldn't do that", it was possible to write code that
+depends on Perl's hashed key order (Data::Dumper does this). The new
+algorithm "One-at-a-Time" produces a different hashed key order.
+More details are in L</"Performance Enhancements">.
=item *
=item *
-The long deprecated uppercase aliases for the string comparison
-operators (EQ, NE, LT, LE, GE, GT) have now been removed.
+The C<package;> syntax (C<package> without an argument) has been
+deprecated. Its semantics were never that clear and its
+implementation even less so. If you have used that feature to
+disallow all but fully qualified variables, C<use strict;> instead.
=item *
-The regular expression captured submatches ($1, $2, ...) are now
-more consistently unset if the match fails, instead of leaving false
-data lying around in them.
+The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
+recognised but now cause fatal errors. The previous behaviour of
+ignoring them by default and warning if requested was unacceptable
+since it, in a way, falsely promised that the features could be used.
=item *
-The tr///C and tr///U features have been removed and will not return;
-the interface was a mistake. Sorry about that. For similar
-functionality, see pack('U0', ...) and pack('C0', ...).
+The current user-visible implementation of pseudo-hashes (the weird
+use of the first array element) is deprecated starting from Perl 5.8.0
+and will be removed in Perl 5.10.0, and the feature will be
+implemented differently. Not only is the current interface rather
+ugly, but the current implementation slows down normal array and hash
+use quite noticeably. The C<fields> pragma interface will remain
+available.
=item *
-Although "you shouldn't do that", it was possible to write code that
-depends on Perl's hashed key order (Data::Dumper does this). The new
-algorithm "One-at-a-Time" produces a different hashed key order.
-More details are in L</"Performance Enhancements">.
+The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
=item *
-The list of filenames from glob() (or <...>) is now by default sorted
-alphabetically to be csh-compliant. (bsd_glob() does still sort platform
-natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
+After years of trying the suidperl is considered to be too complex to
+ever be considered truly secure. The suidperl functionality is likely
+to be removed in a future release.
-=back
+=item *
-=head1 Core Enhancements
+The long deprecated uppercase aliases for the string comparison
+operators (EQ, NE, LT, LE, GE, GT) have now been removed.
-=head2 AUTOLOAD Is Now Lvaluable
+=item *
-AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
-to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
+The tr///C and tr///U features have been removed and will not return;
+the interface was a mistake. Sorry about that. For similar
+functionality, see pack('U0', ...) and pack('C0', ...).
+
+=back
+
+=head1 Core Enhancements
=head2 PerlIO is Now The Default
creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
the child process.
-=item *
-
-The following builtin functions are now overridable: chop(), chomp(),
-each(), keys(), pop(), push(), shift(), splice(), unshift().
-
-=item *
-
-Formats now support zero-padded decimal fields.
+=back
-=item *
+=head2 Safe Signals
-Perl now tries internally to use integer values in numeric conversions
-and basic arithmetics (+ - * /) if the arguments are integers, and
-tries also to keep the results stored internally as integers.
-This change leads into often slightly faster and always less lossy
-arithmetics. (Previously Perl always preferred floating point numbers
-in its math.)
+Perl used to be fragile in that signals arriving at inopportune moments
+could corrupt Perl's internal state. Now Perl postpones handling of
+signals until it's safe (between opcodes).
-=item *
+This change may have surprising side effects because signals no more
+interrupt Perl instantly. Perl will now first finish whatever it was
+doing, like finishing an internal operation (like sort()) or an
+external operation (like an I/O operation), and only then look at any
+arrived signals (and before starting the next operation). No more corrupt
+internal state since the current operation is always finished first,
+but the signal may take more time to get heard.
-The printf() and sprintf() now support parameter reordering using the
-C<%\d+\$> and C<*\d+\$> syntaxes. For example
+=head2 Unicode Overhaul
- print "%2\$s %1\$s\n", "foo", "bar";
+Unicode in general should be now much more usable than in Perl 5.6.0
+(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
+regular expressions should work now, Unicode in tr/// should work now,
+Unicode in I/O should work now.
-will print "bar foo\n"; This feature helps in writing
-internationalised software.
+=over 4
=item *
-Unicode in general should be now much more usable. Unicode can be
-used in hash keys, Unicode in regular expressions should work now,
-Unicode in tr/// should work now (though tr/// seems to be a
-particularly tricky to get right, so you have been warned)
+The Unicode Character Database coming with Perl has been upgraded
+to Unicode 3.1.1. For more information, see http://www.unicode.org/.
=item *
-The Unicode Character Database coming with Perl has been upgraded
-to Unicode 3.1. For more information, see http://www.unicode.org/,
-and http://www.unicode.org/unicode/reports/tr27/
-
For developers interested in enhancing Perl's Unicode capabilities:
almost all the UCD files are included with the Perl distribution in
-the lib/unicode subdirectory. The most notable omission, for space
+the lib/unicore subdirectory. The most notable omission, for space
considerations, is the Unihan database.
=item *
=back
-=head2 Signals Are Now Safe
-
-Perl used to be fragile in that signals arriving at inopportune moments
-could corrupt Perl's internal state.
-
=head2 Understanding of Numbers
In general a lot of fixing has happened in the area of Perl's
and C<atof()> seem to have bugs, Perl tries to work around their
deficiencies. This results hopefully in more accurate numbers.
+Perl now tries internally to use integer values in numeric conversions
+and basic arithmetics (+ - * /) if the arguments are integers, and
+tries also to keep the results stored internally as integers.
+This change leads to often slightly faster and always less lossy
+arithmetics. (Previously Perl always preferred floating point numbers
+in its math.)
+
+=head2 Miscellaneous Enhancements
+
=over 4
=item *
+AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
+to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
+
+=item *
+
C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
in multiple arguments.)
=item *
-Lexicals I: lexicals outside an eval "" weren't resolved
-correctly inside a subroutine definition inside the eval "" if they
-were not already referenced in the top level of the eval""ed code.
-
-=item *
-
-Lexicals II: lexicals leaked at file scope into subroutines that
-were declared before the lexicals.
+Formats now support zero-padded decimal fields.
=item *
Lvalue subroutines can now return C<undef> in list context.
+However, the lvalue subroutine feature still remains experimental.
=item *
=item *
+The following builtin functions are now overridable: each(), keys(),
+pop(), push(), shift(), splice(), unshift().
+
+=item *
+
C<pack('U0a*', ...)> can now be used to force a string to UTF8.
=item *
=item *
-prototype(\&) is now available.
+The printf() and sprintf() now support parameter reordering using the
+C<%\d+\$> and C<*\d+\$> syntaxes. For example
+
+ print "%2\$s %1\$s\n", "foo", "bar";
+
+will print "bar foo\n". This feature helps in writing
+internationalised software, and in general when the order
+of the parameters can vary.
=item *
-Right-hand side magic (GMAGIC) could in many cases such as string
-concatenation be invoked too many times.
+prototype(\&) is now available.
=item *
-The rules for allowing underscores (underbars) in numeric constants
-have been relaxed and simplified: now you can have an underscore
-simply B<between digits>.
+prototype(\[$@%&]) is now available to implicitly create references
+(useful for example if you want to emulate the tie() interface).
=item *
-An UNTIE method is now available.
+untie() will now call an UNTIE() hook if it exists. See L<perltie>
+for details.
=item *
=item *
-C<eval "v200"> now works.
+The rules for allowing underscores (underbars) in numeric constants
+have been relaxed and simplified: now you can have an underscore
+simply B<between digits>.
=back
=head1 Modules and Pragmata
-=head2 New Modules
+=head2 New Modules and Pragmata
=over 4
# later, in some package using or inheriting from MyPack...
my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
-
+
Both variables and routines can have attribute handlers. Handlers can
be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
exact compilation phase (BEGIN, CHECK, INIT, or END).
=item *
+C<Devel::PPPort>, originally from Kenneth Albanowski and now
+maintained by Paul Marquess, has been added. It is primarily used
+by C<h2xs> to enhance portability of of XS modules between different
+versions of Perl.
+
+=item *
+
C<Digest>, frontend module for calculating digests (checksums), from
Gisle Aas, has been added. See L<Digest>.
print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
NOTE: the C<MD5> backward compatibility module is deliberately not
-included since its use is discouraged.
+included since its further use is discouraged.
=item *
=item *
C<I18N::LangTags> has functions for dealing with RFC3066-style
-language tags, by Sean Burke. See <I18N::LangTags>.
+language tags, by Sean Burke. See L<I18N::LangTags>.
=item *
=item *
C<List::Util> is a selection of general-utility list subroutines, like
-sum(), min(), first(), and shuffle(), by Graham barr. See L<List::Util>.
+sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
=item *
necessary to use it with PerlIO::Via as in :
use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+ open($fh,">Via(MIME::QuotedPrint)",$path);
See L<MIME::QuotedPrint>.
=item *
+C<open> is a new pragma for setting the default I/O disciplines
+for open().
+
+=item *
+
C<PerlIO::Scalar> provides the implementation of IO to "in memory"
Perl scalars as discussed above, from Nick Ing-Simmons. It also
serves as an example of a loadable PerlIO layer. Other future
code), from Nick Ing-Simmons.
use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+ open($fh,">Via(MIME::QuotedPrint)",$path);
This will automatically convert everything output to C<$fh>
to Quoted-Printable. See L<PerlIO::Via>.
=item *
+C<Pod::ParseLink>, by Russ Allbery, has been added,
+to parse LZ<><> links in pods as described in the new
+perlpodspec.
+
+=item *
+
C<Pod::Text::Overstrike>, by Joe Smith, has been added.
It converts POD data to formatted overstrike text.
See L<Pod::Text::Overstrike>.
=item *
+C<sort> is a new pragma for controlling the behaviour of sort().
+
+=item *
+
C<Storable> gives persistence to Perl data structures by allowing the
storage and retrieval of Perl data to and from files in a fast and
compact binary format, from Raphael Manfredi. See L<Storable>.
=item *
-C<Test::Simple> has the- basic utilities for writing tests, by Michael
+C<Test::Simple> has basic utilities for writing tests, by Michael
Schwern. See L<Test::Simple>.
=item *
=item *
-C<threads> is an interface interpreter threads, by Arthur Bergman.
+C<threads> is an interface to interpreter threads, by Arthur Bergman.
Interpreter threads (ithreads) is the new thread model introduced in
-Perl 5.6 but then available only as an internal interface for
-extension writers. See L<threads>.
+Perl 5.6 but only available as an internal interface for extension
+writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
=item *
=item *
C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
-references (unlike the standard Tie::RefHash) The module is contained
-within Tie::RefHash, see L<Tie::RefHash).
+references (unlike the standard Tie::RefHash) The module is contained
+within Tie::RefHash, see L<Tie::RefHash>.
=item *
=item *
-AutoLoader can now be disabled with C<no AutoLoader;>,
+AutoLoader can now be disabled with C<no AutoLoader;>.
=item *
-Data::Dumper has now an option to sort hashes.
+B::Deparse has been significantly enhanced. It now can deparse almost
+all of the standard test suite (so that the tests still succeed).
+There is a make target "test.deparse" for trying this out.
=item *
-The English module can now be used without the infamous performance
-hit by saying
-
- use English '-no_performance_hit';
-
-(Assuming, of course, that one doesn't need the troublesome variables
-C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
-C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
+Class::Struct can now define the classes in compile time.
=item *
-File::Find now has pre- and post-processing callbacks. It also
-correctly changes directories when chasing symbolic links. Callbacks
-(naughtily) exiting with "next;" instead of "return;" now work.
+Class::Struct now assigns the array/hash element if the accessor
+is called with an array/hash element as the B<sole> argument.
=item *
-File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
-prototype mismatch with CORE::glob().
+Data::Dumper has now an option to sort hashes.
=item *
-IPC::Open3 now allows the use of numeric file descriptors.
+Data::Dumper has now an option to dump code references
+using B::Deparse.
=item *
-use lib now works identically to @INC. Removing directories
-with 'no lib' now works.
+DB_File now supports newer Berkeley DB versions, among
+other improvements.
=item *
-C<%INC> now localised in a Safe compartment so that use/require work.
+The English module can now be used without the infamous performance
+hit by saying
-=item *
+ use English '-no_performance_hit';
-The Shell module now has an OO interface.
+(Assuming, of course, that one doesn't need the troublesome variables
+C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
+C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
=item *
-B::Deparse has been significantly enhanced. It now can deparse almost
-all of the standard test suite (so that the tests still succeed).
-There is a make target "test.deparse" for trying this out.
+Fcntl, Socket, and Sys::Syslog have been rewritten to use the
+new-style constant dispatch section (see L<ExtUtils::Constant>).
+This means that they will be more robust and hopefully faster.
=item *
-Class::Struct can now define the classes in compile time.
+File::Find now chdir()s correctly when chasing symbolic links.
=item *
-Class::Struct now assigns the array/hash element if the accessor
-is called with an array/hash element as the B<sole> argument.
+File::Find now has pre- and post-processing callbacks. It also
+correctly changes directories when chasing symbolic links. Callbacks
+(naughtily) exiting with "next;" instead of "return;" now work.
=item *
-Fcntl, Socket, and Sys::Syslog have been rewritten to use the
-new-style constant dispatch section (see L<ExtUtils::Constant>).
+File::Find is now (again) reentrant. It also has been made
+more portable.
=item *
-File::Find is now (again) reentrant. It also has been made
-more portable.
+File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
+prototype mismatch with CORE::glob().
=item *
=item *
+IPC::Open3 now allows the use of numeric file descriptors.
+
+=item *
+
IO::Socket has now atmark() method, which returns true if the socket
is positioned at the out-of-band mark. The method is also exportable
as a sockatmark() function.
=item *
-Math::BigFloat and Math::BigInt have undergone much fixing,
-they are now magnitudes faster, and they support various
-bignum libraries such as GMP and PARI as their backends.
+use lib now works identically to @INC. Removing directories
+with 'no lib' now works.
=item *
-Net::Ping has been enhanced. There is now "external" protocol which
-uses Net::Ping::External module which runs external ping(1) and parses
-the output. An alpha version of Net::Ping::External is available in
-CPAN and in 5.7.2 the Net::Ping::External may be integrated to Perl.
+Math::BigFloat and Math::BigInt have undergone a full rewrite.
+They are now magnitudes faster, and they support various
+bignum libraries such as GMP and PARI as their backends.
+
+=item *
+
+Math::Complex handles inf, NaN etc., better.
=item *
-The C<open> pragma allows layers other than ":raw" and ":crlf" when
-using PerlIO.
+Net::Ping has been enhanced. There is now "external" protocol which
+uses Net::Ping::External module which runs external ping(1) and parses
+the output. A version of Net::Ping::External is available in CPAN.
=item *
=item *
+In Safe the C<%INC> now localised in a Safe compartment so that
+use/require work.
+
+=item *
+
+In SDBM_File on dosish platforms, some keys went missing because of
+lack of support for files with "holes". A workaround for the problem
+has been added.
+
+=item *
+
+In Search::Dict one can now have a pre-processing hook for the
+lines being searched.
+
+=item *
+
+The Shell module now has an OO interface.
+
+=item *
+
The Test module has been significantly enhanced.
=item *
-The C<vars> pragma now supports declaring fully qualified variables.
+The vars pragma now supports declaring fully qualified variables.
(Something that C<our()> does not and will not support.)
=item *
=item *
-h2xs now produces a template README.
+C<h2ph> now supports C trigraphs.
=item *
-L<h2ph> now supports C trigraphs.
+C<h2xs> now produces a template README.
=item *
-L<h2xs> uses the new L<ExtUtils::Constant> module which will affect
+C<h2xs> now uses C<Devel::PPort> for better portability between
+different versions of Perl.
+
+=item *
+
+C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
newly created extensions that define constants. Since the new code is
more correct (if you have two constants where the first one is a
prefix of the second one, the first constant B<never> gets defined),
=item *
-L<libnetcfg> has been added to configure the libnet.
+C<libnetcfg> has been added to configure the libnet.
=item *
-perlbug is now much more robust. It also sends the bug report to
+C<perlbug> is now much more robust. It also sends the bug report to
perl.org, not perl.com.
=item *
-perlcc has been rewritten and its user interface (that is,
+C<perlcc> has been rewritten and its user interface (that is,
command line) is much more like that of the UNIX C compiler, cc.
+(The perlbc tools has been removed. Use C<perlcc -B> instead.)
=item *
-perlivp is a new utility for doing Installation Verification
-Procedure after installing Perl.
+C<perlivp> is a new Installation Verification Procedure utility
+for running any time after installing Perl.
=item *
-pod2html now allows specifying a cache directory.
+C<pod2html> now allows specifying a cache directory.
=item *
-s2p has been completely rewritten in Perl. (It is in fact a full
-implementation of sed in Perl.)
+C<s2p> has been completely rewritten in Perl. (It is in fact a full
+implementation of sed in Perl: you can use the sed functionality by
+using the C<psed> utility.)
=item *
-xsubpp now understands POD documentation embedded in the *.xs files.
+C<xsubpp> now understands POD documentation embedded in the *.xs files.
=item *
-xsubpp now supports OUT keyword.
+C<xsubpp> now supports OUT keyword.
=back
=item *
perlebcdic contains considerations for running Perl on EBCDIC platforms.
-Note that unfortunately EBCDIC platforms that used to supported back in
-Perl 5.005 are still unsupported by Perl 5.7.0; the plan, however, is to
-bring them back to the fold.
=item *
=item *
+perlpacktut is a pack() tutorial.
+
+=item *
+
perlpod has been rewritten to be clearer and to record the best
practices gathered over the years.
=item *
-perlpodstyle is a more formal specification of the pod format,
+perlpodspec is a more formal specification of the pod format,
mainly of interest for writers of pod applications, not to
people writing in pod.
=item *
-perlposix-bc explains using Perl on the POSIX-BC platform
-(an EBCDIC mainframe platform).
-
-=item *
-
perlretut is a regular expression tutorial.
=item *
=item *
-map() that changes the size of the list should now work faster.
-
-=item *
-
-sort() has been changed to use mergesort internally as opposed to the
-earlier quicksort. For very small lists this may result in slightly
-slower sorting times, but in general the speedup should be at least
-20%. Additional bonuses are that the worst case behaviour of sort()
-is now better (in computer science terms it now runs in time O(N log N),
-as opposed to quicksort's Theta(N**2) worst-case run time behaviour),
-and that sort() is now stable (meaning that elements with identical
-keys will stay ordered as they were before the sort).
+map() could get pathologically slow when the result list it generates
+is larger than the source list. The performance has been improved for
+common scenarios.
+
+=item *
+
+sort() has been changed to use primarily mergesort internally as
+opposed to the earlier quicksort. For very small lists this may
+result in slightly slower sorting times, but in general the speedup
+should be at least 20%. Additional bonuses are that the worst case
+behaviour of sort() is now better (in computer science terms it now
+runs in time O(N log N), as opposed to quicksort's Theta(N**2)
+worst-case run time behaviour), and that sort() is now stable
+(meaning that elements with identical keys will stay ordered as they
+were before the sort). See the C<sort> pragma for information.
+
+The story in more detail: suppose you want to serve yourself a little
+slice of Pi.
+
+ @digits = ( 3,1,4,1,5,9 );
+
+A numerical sort of the digits will yield (1,1,3,4,5,9), as expected.
+Which C<1> comes first is hard to know, since one C<1> looks pretty
+much like any other. You can regard this as totally trivial,
+or somewhat profound. However, if you just want to sort the even
+digits ahead of the odd ones, then what will
+
+ sort { ($a % 2) <=> ($b % 2) } @digits;
+
+yield? The only even digit, C<4>, will come first. But how about
+the odd numbers, which all compare equal? With the quicksort algorithm
+used to implement Perl 5.6 and earlier, the order of ties is left up
+to the sort. So, as you add more and more digits of Pi, the order
+in which the sorted even and odd digits appear will change.
+and, for sufficiently large slices of Pi, the quicksort algorithm
+in Perl 5.8 won't return the same results even if reinvoked with the
+same input. The justification for this rests with quicksort's
+worst case behavior. If you run
+
+ sort { $a <=> $b } ( 1 .. $N , 1 .. $N );
+
+(something you might approximate if you wanted to merge two sorted
+arrays using sort), doubling $N doesn't just double the quicksort time,
+it I<quadruples> it. Quicksort has a worst case run time that can
+grow like N**2, so-called I<quadratic> behaviour, and it can happen
+on patterns that may well arise in normal use. You won't notice this
+for small arrays, but you I<will> notice it with larger arrays,
+and you may not live long enough for the sort to complete on arrays
+of a million elements. So the 5.8 quicksort scrambles large arrays
+before sorting them, as a statistical defence against quadratic behaviour.
+But that means if you sort the same large array twice, ties may be
+broken in different ways.
+
+Because of the unpredictability of tie-breaking order, and the quadratic
+worst-case behaviour, quicksort was I<almost> replaced completely with
+a stable mergesort. I<Stable> means that ties are broken to preserve
+the original order of appearance in the input array. So
+
+ sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
+
+will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers
+appear in the output in the same order they appeared in the input.
+Mergesort has worst case O(NlogN) behaviour, the best value
+attainable. And, ironically, this mergesort does particularly
+well where quicksort goes quadratic: mergesort sorts (1..$N, 1..$N)
+in O(N) time. But quicksort was rescued at the last moment because
+it is faster than mergesort on certain inputs and platforms.
+For example, if you really I<don't> care about the order of even
+and odd digits, quicksort will run in O(N) time; it's very good
+at sorting many repetitions of a small number of distinct elements.
+The quicksort divide and conquer strategy works well on platforms
+with relatively small, very fast, caches. Eventually, the problem gets
+whittled down to one that fits in the cache, from which point it
+benefits from the increased memory speed.
+
+Quicksort was rescued by implementing a sort pragma to control aspects
+of the sort. The B<stable> subpragma forces stable behaviour,
+regardless of algorithm. The B<_quicksort> and B<_mergesort>
+subpragmas are heavy-handed ways to select the underlying implementation.
+The leading C<_> is a reminder that these subpragmas may not survive
+beyond 5.8. More appropriate mechanisms for selecting the implementation
+exist, but they wouldn't have arrived in time to save quicksort.
=item *
=item *
+Configure support for pdp11-style memory models has been removed due
+to obsolescence.
+
+=item *
+
configure.gnu now works with options with whitespace in them.
=item *
=item *
+If your file system supports symbolic links you can build Perl outside
+of the source directory by
+
+ mkdir /tmp/perl/build/directory
+ cd /tmp/perl/build/directory
+ sh /path/to/perl/source/Configure -Dmksymlinks ...
+
+This will create in /tmp/perl/build/directory a tree of symbolic links
+pointing to files in /path/to/perl/source. The original files are left
+unaffected. After Configure has finished you can just say
+
+ make all test
+
+and Perl will be built and tested, all in /tmp/perl/build/directory.
+
+=item *
+
For Perl developers several new make targets for profiling
and debugging have been added, see L<perlhack>.
=item *
+NEC SUPER-UX is now supported.
+
+=item *
+
Amdahl UTS UNIX mainframe platform is now supported.
=item *
=head1 Selected Bug Fixes
+Numerous memory leaks and uninitialized memory accesses have been
+hunted down. Most importantly anonymous subs used to leak quite
+a bit.
+
=over 4
=item *
+The autouse pragma didn't work for Multi::Part::Function::Names.
+
+=item *
+
+caller() could cause core dumps in certain situations. Carp was sometimes
+affected by this problem.
+
+=item *
+
+chop(@list) in list context returned the characters chopped in
+reverse order. This has been reversed to be in the right order.
+
+=item *
+
+Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
+when building the Perl binary. The only exception to this is SunOS 4.x,
+which needs them.
+
+=item *
+
+The behaviour of non-decimal but numeric string constants such as
+"0x23" was platform-dependent: in some platforms that was seen as 35,
+in some as 0, in some as a floating point number (don't ask). This
+was caused by Perl using the operating system libraries in a situation
+where the result of the string to number conversion is undefined: now
+Perl consistently handles such strings as zero in numeric contexts.
+
+=item *
+
+The order of DESTROYs has been made more predictable.
+
+=item *
+
Several debugger fixes: exit code now reflects the script exit code,
condition C<"0"> now treated correctly, the C<d> command now checks
-line number, the C<$.> no longer gets corrupted, all debugger output now
-goes correctly to the socket if RemotePort is set.
+line number, the C<$.> no longer gets corrupted, all debugger output
+now goes correctly to the socket if RemotePort is set.
+
+=item *
+
+Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
+when statically building extensions into perl. This has been corrected.
+
+=item *
+
+L<dprofpp> -R didn't work.
=item *
C<*foo{FORMAT}> now works.
+=item *
+
+Infinity is now recognized as a number.
=item *
-Lexical warnings now propagating correctly between scopes.
+UNIVERSAL::isa no longer caches methods incorrectly. (This broke
+the Tk extension with 5.6.0.)
+
+=item *
+
+Lexicals I: lexicals outside an eval "" weren't resolved
+correctly inside a subroutine definition inside the eval "" if they
+were not already referenced in the top level of the eval""ed code.
+
+=item *
+
+Lexicals II: lexicals leaked at file scope into subroutines that
+were declared before the lexicals.
+
+=item *
+
+Lexical warnings now propagating correctly between scopes
+and into C<eval "...">.
+
+=item *
+
+C<use warnings qw(FATAL all)> did not work as intended. This has been
+corrected.
+
+=item *
+
+warnings::enabled() now reports the state of $^W correctly if the caller
+isn't using lexical warnings.
=item *
=item *
+mkdir() now ignores trailing slashes in the directory name,
+as mandated by POSIX.
+
+=item *
+
+Some versions of glibc have a broken modfl(). This affects builds
+with C<-Duselongdouble>. This version of Perl detects this brokenness
+and has a workaround for it. The glibc release 2.2.2 is known to have
+fixed the modfl() bug.
+
+=item *
+
Modulus of unsigned numbers now works (4063328477 % 65535 used to
return 27406, instead of 27047).
=item *
+Numeric conversions did not recognize changes in the string value
+properly in certain circumstances.
+
+=item *
+
+Attributes (like :shared) didn't work with our().
+
+=item *
+
our() variables will not cause "will not stay shared" warnings.
=item *
+"our" variables of the same name declared in two sibling blocks
+resulted in bogus warnings about "redeclaration" of the variables.
+The problem has been corrected.
+
+=item *
+
pack "Z" now correctly terminates the string with "\0".
=item *
=item *
+The PERL5OPT environment variable (for passing command line arguments
+to Perl) didn't work for more than a single group of options.
+
+=item *
+
+PERL5OPT with embedded spaces didn't work.
+
+=item *
+
printf() no longer resets the numeric locale to "C".
=item *
-C<q(a\\b)> now parses correctly as C<'a\\b'>.
+C<qw(a\\b)> now parses correctly as C<'a\\b'>.
+
+=item *
+
+pos() did not return the correct value within s///ge in earlier
+versions. This is now handled correctly.
=item *
=item *
+Right-hand side magic (GMAGIC) could in many cases such as string
+concatenation be invoked too many times.
+
+=item *
+
scalar() now forces scalar context even when used in void context.
=item *
+SOCKS support is now much more robust.
+
+=item *
+
sort() arguments are now compiled in the right wantarray context
(they were accidentally using the context of the sort() itself).
+The comparison block is now run in scalar context, and the arguments
+to be sorted are always provided list context.
=item *
Changed the POSIX character class C<[[:space:]]> to include the (very
-rare) vertical tab character. Added a new POSIX-ish character class
-C<[[:blank:]]> which stands for horizontal whitespace (currently,
-the space and the tab).
+rarely used) vertical tab character. Added a new POSIX-ish character
+class C<[[:blank:]]> which stands for horizontal whitespace
+(currently, the space and the tab).
=item *
-$AUTOLOAD, sort(), lock(), and spawning subprocesses
-in multiple threads simultaneously are now thread-safe.
+The tainting behaviour of sprintf() has been rationalized. It does
+not taint the result of floating point formats anymore, making the
+behaviour consistent with that of string interpolation.
=item *
-Allow read-only string on left hand side of non-modifying tr///.
+Some cases of inconsistent taint propagation (such as within hash
+values) have been fixed.
=item *
-Several Unicode fixes (but still not perfect).
+The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
+of simple pattern matches. These are now handled better.
-=over 8
+=item *
+
+Regular expression debug output (whether through C<use re 'debug'>
+or via C<-Dr>) now looks better.
=item *
-BOMs (byte order marks) in the beginning of Perl files
-(scripts, modules) should now be transparently skipped.
-UTF-16 (UCS-2) encoded Perl files should now be read correctly.
+Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
+bug has been fixed.
=item *
-The character tables have been updated to Unicode 3.0.1.
+Use of $& could trigger a core dump under some situations. This
+is now avoided.
=item *
-chr() for values greater than 127 now create utf8 when under use
-utf8.
+The regular expression captured submatches ($1, $2, ...) are now
+more consistently unset if the match fails, instead of leaving false
+data lying around in them.
=item *
-Comparing with utf8 data does not magically upgrade non-utf8 data into
-utf8.
+readline() on files opened in "slurp" mode could return an extra "" at
+the end in certain situations. This has been corrected.
=item *
-C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
+Autovivification of symbolic references of special variables described
+in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
+again now.
=item *
-Concatenation with the C<.> operator or via variable interpolation,
-C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
-substitution with C<s///>, single-quoted UTF8, should now work--in
-theory.
+Sys::Syslog ignored the C<LOG_AUTH> constant.
=item *
-The C<tr///> operator now works I<slightly> better but is still rather
-broken. Note that the C<tr///CU> functionality has been removed (but
-see pack('U0', ...)).
+All but the first argument of the IO syswrite() method are now optional.
=item *
-vec() now refuses to deal with characters >255.
+$AUTOLOAD, sort(), lock(), and spawning subprocesses
+in multiple threads simultaneously are now thread-safe.
=item *
-Zero entries were missing from the Unicode classes like C<IsDigit>.
+Tie::ARRAY SPLICE method was broken.
-=back
+=item *
+
+Allow read-only string on left hand side of non-modifying tr///.
=item *
-UNIVERSAL::isa no longer caches methods incorrectly. (This broke
-the Tk extension with 5.6.0.)
+Several Unicode fixes.
+
+=over 8
=item *
-Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
-when building the Perl binary. The only exception to this is SunOS 4.x,
-which needs them.
+BOMs (byte order marks) in the beginning of Perl files
+(scripts, modules) should now be transparently skipped.
+UTF-16 (UCS-2) encoded Perl files should now be read correctly.
=item *
-SOCKS support is now much more robust.
+The character tables have been updated to Unicode 3.1.1.
=item *
-If your file system supports symbolic links you can build Perl outside
-of the source directory by
+Comparing with utf8 data does not magically upgrade non-utf8 data
+into utf8.
- mkdir /tmp/perl/build/directory
- cd /tmp/perl/build/directory
- sh /path/to/perl/source/Configure -Dmksymlinks ...
+=item *
-This will create in /tmp/perl/build/directory a tree of symbolic links
-pointing to files in /path/to/perl/source. The original files are left
-unaffected. After Configure has finished you can just say
+C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
- make all test
+=item *
-and Perl will be built and tested, all in /tmp/perl/build/directory.
+Concatenation with the C<.> operator or via variable interpolation,
+C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
+substitution with C<s///>, single-quoted UTF8, should now work.
+
+=item *
+
+The C<tr///> operator now works. Note that the C<tr///CU>
+functionality has been removed (but see pack('U0', ...)).
+
+=item *
+
+C<eval "v200"> now works.
+
+=item *
+
+Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
+This has been corrected.
+
+=item *
+
+Zero entries were missing from the Unicode classes like C<IsDigit>.
+
+=back
+
+=item *
+
+Large unsigned numbers (those above 2**31) could sometimes lose their
+unsignedness, causing bogus results in arithmetic operations.
=back
All BSDs
-Setting C<$0> now works (as much as possible; see perlvar for details).
+Setting C<$0> now works (as much as possible; see L<perlvar> for details).
=item *
=item *
+Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
+
+=item *
+
EPOC
EPOC update after Perl 5.6.0. See README.epoc.
Linux
+=over 8
+
+=item *
+
Long doubles should now work (see INSTALL).
=item *
+Linux previously had problems related to sockaddrlen when using
+accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
+
+=back
+
+=item *
+
MacOS Classic
Compilation of the standard Perl distribution in MacOS Classic should
chdir() now works better despite a CRT bug; now works with MULTIPLICITY
(see INSTALL); now works with Perl's malloc.
+The tainting of C<%ENV> elements via C<keys> or C<values> was previously
+unimplemented. It now works as documented.
+
+The C<waitpid> emulation has been improved. The worst bug (now fixed)
+was that a pid of -1 would cause a wildcard search of all processes on
+the system. The most significant enhancement is that we can now
+usually get the completion status of a terminated process.
+
+POSIX-style signals are now emulated much better on VMS versions prior
+to 7.0.
+
+The C<system> function and backticks operator have improved
+functionality and better error handling.
+
=item *
Windows
=item *
-Better chdir() return value for a non-existent directory.
+Borland C++ v5.5 is now a supported compiler that can build Perl.
+However, the generated binaries continue to be incompatible with those
+generated by the other supported compilers (GCC and Visual C++).
+
+=item *
+
+Better chdir() return value for a non-existent directory.
+
+=item *
+
+Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
=item *
=item *
+Current directory entries in %ENV are now correctly propagated to child
+processes.
+
+=item *
+
$ENV{LIB} now used to search for libs under Visual C.
=item *
+fork() emulation has been improved in various ways, but still continues
+to be experimental. See L<perlfork> for known bugs and caveats.
+
+=item *
+
A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
=item *
+Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
+Other bugs in chdir() and Cwd::cwd() have also been fixed.
+
+=item *
+
+HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
+
+=item *
+
+The makefiles now provide a single switch to bulk-enable all the features
+enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
+
+=item *
+
Allow REG_EXPAND_SZ keys in the registry.
=item *
=item *
+%SIG has been enabled under USE_ITHREADS, but its use is completely
+unsupported under all configurations.
+
+=item *
+
Less stack reserved per thread so that more threads can run
concurrently. (Still 16M per thread.)
=item *
-C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
+C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
(works better when perl is running as service).
=item *
=item *
-wait() and waitpid() now work much better.
+wait(), waitpid() and backticks now return the correct exit status under
+Windows 9x.
=item *
=head1 New or Changed Diagnostics
+=over 4
+
+=item *
+
All regular expression compilation error messages are now hopefully
easier to understand both because the error message now comes before
the failed regex and because the point of failure is now clearly
-marked.
+marked by a C<E<lt>-- HERE> marker.
+
+=item *
The various "opened only for", "on closed", "never opened" warnings
drop the C<main::> prefix for filehandles in the C<main> package,
-for example C<STDIN> instead of <main::STDIN>.
+for example C<STDIN> instead of C<main::STDIN>.
+
+=item *
The "Unrecognized escape" warning has been extended to include C<\8>,
C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
-=over 4
+=item *
Two new debugging options have been added: if you have compiled your
Perl with debugging, you can use the -DT and -DR options to trace
now give a warning. This may be a problem for generated and evaled
code.
+=item *
+
+If you try to L<perlfunc/pack> a number less than 0 or larger than 255
+using the C<"C"> format you will get an optional warning. Similarly
+for the C<"c"> format and a number less than -128 or more than 127.
+
+=item *
+
+Certain regex modifiers such as C<(?o)> make sense only if applied to
+the entire regex. You will an optional warning if you try to do otherwise.
+
+=item *
+
+Using arrays or hashes as references (e.g. C<< %foo->{bar} >>
+has been deprecated for a while. Now you will get an optional warning.
+
=back
=head1 Changed Internals
=item *
-Added rsignal(), whichsig(), do_join() to the publicised API.
+Added rsignal(), whichsig(), do_join(), op_clear, op_null,
+ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
+interfaces to the publicised API. For the full list of the available
+APIs see L<perlapi>.
=item *
=item *
-Added is_utf8_char(), is_utf8_string(), bytes_to_utf8(), and utf8_to_bytes().
+Now xsubs can have attributes just like subs. (Well, at least the
+built-in attributes.)
=item *
-Now xsubs can have attributes just like subs.
+dTHR and djSP have been obsoleted; the former removed (because it's
+a no-op) and the latter replaced with dSP.
=item *
-Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv().
-For the full list of the available APIs see L<perlapi>.
+PERL_OBJECT has been completely removed.
=item *
-dTHR and djSP have been obsoleted; the former removed (because it's
-a no-op) and the latter replaced with dSP.
+The MAGIC constants (e.g. C<'P'>) have been macrofied
+(e.g. C<PERL_MAGIC_TIED>) for better source code readability
+and maintainability.
=item *
-PERL_OBJECT has been completely removed.
+The regex compiler now maintains a structure that identifies nodes in
+the compiled bytecode with the corresponding syntactic features of the
+original regex expression. The information is attached to the new
+C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
+complete information.
=item *
-Documentation on how to use the Perl source repository has been added
-to F<Porting/repository.pod>.
+The C code has been made much more C<gcc -Wall> clean. Some warning
+messages still remain in some platforms, so if you are compiling with
+gcc you may see some warnings about dubious practices. The warnings
+are being worked on.
=item *
-There are now several profiling make targets
+F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
=item *
-The C<op_clear> and C<op_null> are now exported.
+Documentation on how to use the Perl source repository has been added
+to F<Porting/repository.pod>.
+
+=item *
+
+There are now several profiling make targets.
=back
Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
from all the Perl 5.7 releases), so that particular vulnerability
isn't there anymore. However, further security vulnerabilities are,
-unfortunately, always possible. The suidperl code is being reviewed
-and if deemed too risky to continue to be supported, it may be
-completely removed from future releases. In any case, suidperl should
-only be used by security experts who know exactly what they are doing
-and why they are using suidperl instead of some other solution such as
-sudo (see http://www.courtesan.com/sudo/).
-
-=head1 Selected Bug Fixes
-
-Numerous memory leaks and uninitialized memory accesses have been hunted down.
-Most importantly anonymous subs used to leak quite a bit.
-
-=over 4
-
-=item *
-
-chop(@list) in list context returned the characters chopped in
-reverse order. This has been reversed to be in the right order.
-
-=item *
-
-The order of DESTROYs has been made more predictable.
-
-=item *
-
-mkdir() now ignores trailing slashes in the directory name,
-as mandated by POSIX.
-
-=item *
-
-Attributes (like :shared) didn't work with our().
-
-=item *
-
-The PERL5OPT environment variable (for passing command line arguments
-to Perl) didn't work for more than a single group of options.
-
-=item *
-
-The tainting behaviour of sprintf() has been rationalized. It does
-not taint the result of floating point formats anymore, making the
-behaviour consistent with that of string interpolation.
-
-=item *
-
-All but the first argument of the IO syswrite() method are now optional.
-
-=item *
-
-Tie::ARRAY SPLICE method was broken.
-
-=item *
-
-vec() now tries to work with characters <= 255 when possible, but it leaves
-higher character values in place. In that case, if vec() was used to modify
-the string, it is no longer considered to be utf8-encoded.
-
-=item *
-
-The autouse pragma didn't work for Multi::Part::Function::Names.
-
-=item *
-
-The behaviour of non-decimal but numeric string constants such as
-"0x23" was platform-dependent: in some platforms that was seen as 35,
-in some as 0, in some as a floating point number (don't ask). This
-was caused by Perl using the operating system libraries in a situation
-where the result of the string to number conversion is undefined: now
-Perl consistently handles such strings as zero in numeric contexts.
-
-=item *
-
-L<dprofpp> -R didn't work.
-
-=item *
-
-PERL5OPT with embedded spaces didn't work.
-
-=item *
-
-L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
-
-=item *
-
-Some versions of glibc have a broken modfl(). This affects builds
-with C<-Duselongdouble>. This version of Perl detects this brokenness
-and has a workaround for it. The glibc release 2.2.2 is known to have
-fixed the modfl() bug.
-
-=item *
-
-Linux previously had problems related to sockaddrlen when using
-accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
-
-=item *
-
-Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
-
-=item *
-
-Windows
-
-=over 8
-
-=item *
-
-Borland C++ v5.5 is now a supported compiler that can build Perl.
-However, the generated binaries continue to be incompatible with those
-generated by the other supported compilers (GCC and Visual C++).
-
-=item *
-
-Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
-Other bugs in chdir() and Cwd::cwd() have also been fixed.
-
-=item *
-
-Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
-
-=item *
-
-HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
-
-=item *
-
-The makefiles now provide a single switch to bulk-enable all the features
-enabled in ActiveState ActivePerl (a popular binary distribution).
-
-=back
+unfortunately, always possible. The suidperl functionality is most
+probably going to be removed in Perl 5.10. In any case, suidperl
+should only be used by security experts who know exactly what they are
+doing and why they are using suidperl instead of some other solution
+such as sudo (see http://www.courtesan.com/sudo/).
=head1 New Tests
-Several new tests have been added, especially for the F<lib> subsection.
+Several new tests have been added, especially for the F<lib>
+subsection. There are now about 34 000 individual tests (spread over
+about 530 test scripts), in the regression suite (5.6.1 has about
+11700 tests, in 258 test scripts) Many of the new tests are introduced
+by the new modules, but still in general Perl is now more thoroughly
+tested.
+
+Because of the large number of tests, running the regression suite
+will take considerably longer time than it used to: expect the suite
+to take up to 4-5 times longer to run than in perl 5.6. In a really
+fast machine you can hope to finish the suite in about 5 minutes
+(wallclock time).
The tests are now reported in a different order than in earlier Perls.
(This happens because the test scripts from under t/lib have been moved
to be closer to the library/extension they are testing.)
-=head1 New or Changed Diagnostics
-
-=over 4
-
-=item *
-
-In the regular expression diagnostics the C<E<lt>E<lt> HERE> marker
-introduced in 5.7.0 has been changed to be C<E<lt>-- HERE> since too
-many people found the C<E<lt>E<lt>> to be too similar to here-document
-starters.
-
-=item *
-
-If you try to L<perlfunc/pack> a number less than 0 or larger than 255
-using the C<"C"> format you will get an optional warning. Similarly
-for the C<"c"> format and a number less than -128 or more than 127.
-
-=item *
-
-Certain regex modifiers such as C<(?o)> make sense only if applied to
-the entire regex. You will an optional warning if you try to do otherwise.
-
-=item *
-
-Using arrays or hashes as references (e.g. C<%foo->{bar}> has been
-deprecated for a while. Now you will get an optional warning.
-
-=back
-
-=head1 Source Code Enhancements
-
-=head2 MAGIC constants
-
-The MAGIC constants (e.g. C<'P'>) have been macrofied
-(e.g. C<PERL_MAGIC_TIED>) for better source code readability
-and maintainability.
-
-=head2 Better commented code
-
-F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
-
-=head2 Regex pre-/post-compilation items matched up
-
-The regex compiler now maintains a structure that identifies nodes in
-the compiled bytecode with the corresponding syntactic features of the
-original regex expression. The information is attached to the new
-C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
-complete information.
-
-=head2 gcc -Wall
-
-The C code has been made much more C<gcc -Wall> clean. Some warning
-messages still remain, though, so if you are compiling with gcc you
-will see some warnings about dubious practices. The warnings are
-being worked on.
-
=head1 Known Problems
-Note that unlike other sections in this document (which describe
-changes since 5.7.0) this section is cumulative containing known
-problems for all the 5.7 releases.
-
=head2 AIX
=over 4
=head2 Amiga Perl Invoking Mystery
One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
-works, but for example C<bin:perl -v> doesn't. The exact reason is
+works, but for example C<bin:perl -v> doesn't. The exact reason isn't
known but the current suspect is the F<ixemul> library.
=head2 lib/ftmp-security tests warn 'system possibly insecure'
No known fix.
+=head2 Mac OS X
+
+The following tests are known to fail:
+
+ Failed Test Stat Wstat Total Fail Failed List of Failed
+ -------------------------------------------------------------------------
+ ../ext/DB_File/t/db-btree.t 0 11 ?? ?? % ??
+ ../ext/DB_File/t/db-recno.t 149 3 2.01% 61 63 65
+ ../ext/POSIX/t/posix.t 31 1 3.23% 10
+ ../lib/warnings.t 450 1 0.22% 316
+
=head2 OS/390
OS/390 has rather many test failures but the situation is actually
=head2 Failure of Thread tests
-B<Note that support for 5.005-style threading remains experimental.>
+B<Note that support for 5.005-style threading remains experimental
+and practically unsupported.>
The following tests are known to fail due to fundamental problems in
the 5.005 threading implementation. These are not new failures--Perl
5.005_0x has the same bugs, but didn't have these tests.
- lib/autouse.t 4
- t/lib/thr5005.t 19-20
+ ext/List/Util/t/first 2
+ lib/autouse 4
+ ext/Thread/thr5005 19-20
+
+These failures are unlikely to get fixed.
=head2 UNICOS
=head2 VMS
-Rather many tests are failing in VMS but that actually more tests
-succeed in VMS than they used to, it's just that there are many,
-many more tests than there used to be.
-
-Here are the known failures from some compiler/platform combinations.
-
-DEC C V5.3-006 on OpenVMS VAX V6.2
+There is one known test failure with a default configuration:
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.ext.posix]sigaction..................FAILED on test 7
- [-.ext.time.hires]hires.................FAILED on test 14
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.math.bigint.t]bigintpm...........FAILED on test 1183
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- [.op]sprintf............................FAILED on test 12
- Failed 8/399 tests, 91.23% okay.
-
-DEC C V6.0-001 on OpenVMS Alpha V7.2-1 and
-Compaq C V6.2-008 on OpenVMS Alpha V7.1
-
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- Failed 4/399 tests, 92.48% okay.
-
-Compaq C V6.4-005 on OpenVMS Alpha 7.2.1
-
- [-.ext.b]showlex........................FAILED on test 1
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- [.op]misc...............................FAILED on test 49
- Failed 6/401 tests, 92.77% okay.
-
+ [.run]switches..........................FAILED on test 1
+
=head2 Win32
In multi-CPU boxes there are some problems with the I/O buffering:
Code like the above is known to leak memory every time the local()
is executed.
+=head2 Localising Tied Arrays and Hashes Is Broken
+
+ local %tied_array;
+
+doesn't work as one would expect: the old value is restored
+incorrectly.
+
=head2 Self-tying of Arrays and Hashes Is Forbidden
Self-tying of arrays and hashes is broken in rather deep and
frustrated at the mysterious results (core dumps, most often) it is
for now forbidden (you will get a fatal error even from an attempt).
-=head2 Variable Attributes are not Currently Usable for Tieing
-
-This limitation will hopefully be fixed in future. (Subroutine
-attributes work fine for tieing, see L<Attribute::Handlers>).
-
=head2 Building Extensions Can Fail Because Of Largefiles
Some extensions like mod_perl are known to have issues with
all binaries with different ideas about file offsets, all this is
platform-dependent.
+=head2 Unicode Support on EBCDIC Still Spotty
+
+Though mostly working, Unicode support still has problem spots on
+EBCDIC platforms. One such known spot are the C<\p{}> and C<\P{}>
+regular expression constructs for code points less than 256: the
+pP are testing for Unicode code points, not knowing about EBCDIC.
+
=head2 The Compiler Suite Is Still Experimental
-The compiler suite is slowly getting better but is nowhere near
-working order yet.
+The compiler suite is slowly getting better but it continues to be
+highly experimental. Use in production environments is discouraged.
-=head2 The Long Double Support is Still Experimental
+=head2 The Long Double Support Is Still Experimental
The ability to configure Perl's numbers to use "long doubles",
floating point numbers of hopefully better accuracy, is still
operations are more likely to be executed by less optimised
libraries).
+=head2 Seen In Perl 5.7 But Gone Now
+
+Some modules were seen in the Perl 5.7 development releases
+but are not present in 5.8.0.
+
+=over 4
+
+=item *
+
+C<Attribute::Handlers> was removed because the implementation of C<my>
+variable attributes changed so much that the Attribute::Handlers will
+require a major rewrite. (This means that you can't use
+Attribute::Handler 0.76 with Perl 5.8.0.)
+
+=item *
+
+C<Time::Piece> (previously known as C<Time::Object>) was removed
+because it was felt that it didn't have enough value in it to be a
+core module. It is still a useful module, though, and is available
+from the CPAN.
+
+=back
+
=head1 Reporting Bugs
If you find what you think is a bug, you might check the articles
projects / p5sagit/p5-mst-13.2.git / blobdiff