installations and as far as is known affects only the Linux platform.
You should upgrade your Perl to 5.6.1 as soon as possible. Patches
-for earlier releases exist but they require full recompilation from
-the source code so 5.6.1 is your best choice.
+for earlier releases exist but using the patches require full
+recompilation from the source code anyway, so 5.6.1 is your best
+choice.
+
See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
for more information.
=head1 Incompatible Changes
+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,
+usually the system malloc on such platforms are much better optimized
+for such large memory models than the Perl malloc.
+
=head1 Future Deprecations
The current user-visible implementation of pseudo-hashes (the weird
current implementation slows down normal array and hash use quite
noticeably. The 'fields' pragma interface will remain available.
+The suidperl is also considered to be too much a risk to continue
+maintaining and the suidperl code is likely to be removed in a future
+release.
+
=head1 Core Enhancements
+In general a lot of fixing has happened in the area of Perl's understanding
+of numbers, both integer and floating point. Since in many systems the
+standard number parsing functions like C<strtoul()> and C<atof()> seem
+to have bugs, Perl tries to work around their deficiencies. This results
+hopefully in more accurate numbers.
+
+=over 4
+
+=item *
+
+The rules for allowing underscores (underbars) in numeric constants
+have been relaxed and simplified: now you can have an underscore
+B<between digits>.
+
+=item *
+
+VMS now works under PerlIO.
+
+=item *
+
+GMAGIC (right-hand side magic) could in many cases such as concatenation
+of string be invoked too many times.
+
+=item *
+
+The MAGIC constants (e.g. C<'P'>) have been macrofied
+(e.g. C<PERL_MAGIC_TIED>) for better source code readability
+and maintainability.
+
+=item *
+
+The C<op_clear> and C<op_null> are now exported.
+
+=item *
+
+The Perl parser has been stress tested using both random input and
+Markov chain input.
+
+=back
+
=head1 Modules and Pragmata
=head2 New Modules
+=over 4
+
+=item *
+
+Attribute::Handlers - Simpler definition of attribute handlers
+
+=item *
+
+ExtUtils::Constant - generate XS code to import C header constants
+
+=item *
+
+I18N::LangTags - functions for dealing with RFC3066-style language tags
+
+=item *
+
+List::Util - selection of general-utility list subroutines
+
+=item *
+
+Locale::Maketext - framework for localization
+
+=item *
+
+NEXT - pseudo-class for method redispatch
+
+=item *
+
+Scalar::Util - selection of general-utility scalar subroutines
+
+=item *
+
+Time::HiRes - high resolution ualarm, usleep, and gettimeofday
+
+=back
+
=head2 Updated And Improved Modules and Pragmata
+=over 4
+
+=item *
+
+L<B::Deparse> module has been significantly enhanced. It now
+can deparse almost all of the standard test suite (so that the
+tests still succeed).
+
+=item *
+
+L<Class::Struct> now assigns the array/hash element if the accessor
+is called with an array/hash element as the B<sole> argument.
+
+=item *
+
+L<Cwd> extension is now (even) faster.
+
+=item *
+
+L<DB_File> extension has been updated to version 1.77.
+
+=item *
+
+L<Fcntl>, L<Socket>, and L<Sys::Syslog> have been rewritten to use the
+new-style constant dispatch section (see L<ExtUtils::Constant>).
+
+=item *
+
+L<File::Glob> now supports C<GLOB_LIMIT> constant to limit the
+size of the returned list of filenames.
+
+=back
+
=head1 Performance Enhancements
=head1 Utility Changes
+=over 4
+
+=item *
+
+L<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),
+less lossy (it uses integers for integer constant, as opposed to the
+old code that used floating point numbers even for integer constants),
+and slightly faster, you might want to consider regenerating your
+extension code (the new scheme makes regenerating easy).
+
+=item *
+
+The F<emacs/e2ctags.pl> is now much faster.
+
+=item *
+
+The F<Pod::Html> (and thusly L<pod2html>) now allows specifying
+a cache directory.
+
+=back
+
=head1 New Documentation
+=over 4
+
+=item *
+
+L<Locale::Maketext::TPJ13> is an article about software localization,
+originally published in The Perl Journal #13, republished here with
+kind permission.
+
+=item *
+
+More README.$PLATFORM files have been converted into pod, which also
+means that they also be installed as perl$PLATFORM documentation
+files. The new files are L<perlapollo>, L<perlbeos>, L<perldgux>,
+L<perlhurd>, L<perlmint>, L<perlplan9>, L<perlqnx>, and L<perltru64>.
+
+=item *
+
+The F<Todo> and F<Todo-5.6> files have been merged into L<perltodo>.
+
+=item *
+
+Use of the F<gprof> tool to profile Perl has been documented in L<perlhack>.
+
+=back
+
=head1 Installation and Configuration Improvements
=head2 New Or Improved Platforms
+=over 4
+
+=item *
+
+AIX should now work better with gcc. Also longdouble support in
+AIX should be better now.
+
+=item *
+
+AtheOS (http://www.atheos.cx/) is a new platform.
+
+=item *
+
+DG/UX platform now supports the 5.005-style threads.
+
+=item *
+
+MacOS (Classic) [HOPEFULLY]
+
+=item *
+
+MacOS X (or Darwin) should now be able to build Perl even on HFS+ filesystem.
+(The case-insensitivity confused the Perl build process.)
+
+=item *
+
+Netware [HOPEFULLY]
+
+=item *
+
+The Amdahl UTS UNIX mainframe platform is now supported.
+
+=back
+
=head2 Generic Improvements
+=over 4
+
+=item *
+
+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.
+
+=item *
+
+In AFS installations one can configure the root of the AFS to be
+somewhere else than the default F</afs> by using the Configure
+parameter C<-Dafsroot=/some/where/else>.
+
+=item *
+
+The version of Berkeley DB used when the Perl (and, presumably, the
+DB_File extension) was built is now available as
+C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
+from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
+DB_VERSION_PATCH_CFG> from C.
+
+=item *
+
+The Thread extension is not built at all under ithreads (C<Configure
+-Duseithreads>) because it wouldn't work anyway (the Thread extension
+requires being Configured with C<-Duse5005threads>).
+
+=item *
+
+The C<B::Deparse> compiler backend has been so significantly improved
+that almost the whole Perl test suite passes after being deparsed. A
+make target has been added to help in further testing: C<make test.deparse>.
+
+=back
+
=head1 Selected Bug Fixes
=head2 Platform Specific Changes and Fixes
+=over 4
+
+=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.
+
+=back
+
=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 Changed Internals
=head2 Regex pre-/post-compilation items matched up
=head1 New Tests
+Several new tests have been added, especially for the F<lib> subsection.
+
+=back
+
+The test F<camel-III/vstring> has been merged with F<op/ver>.
+
=head1 Known Problems
Note that unlike other sections in this document (which describe