To be consistent with pack(), the C<C0> in unpack() templates indicates
that the data is to be processed in character mode, i.e. character by
-character; at the contrary, C<U0> in unpack() indicates UTF-8 mode, where
+character; on the contrary, C<U0> in unpack() indicates UTF-8 mode, where
the packed string is processed in its UTF-8-encoded Unicode form on a byte
by byte basis. This is reversed with regard to perl 5.8.X.
octal.
The B<-C> option can no longer be used on the C<#!> line. It wasn't
-working anyway.
+working there anyway.
=head1 Core Enhancements
dedicated, single purpose security tools such as C<sudo> in preference to
C<suidperl>.
+=head2 PERLIO_DEBUG
+
+The C<PERLIO_DEBUG> environment variable has no longer any effect for
+setuid scripts and for scripts run with B<-T>.
+
+Moreover, with a thread-enabled perl, using C<PERLIO_DEBUG> could lead to
+an internal buffer overflow. This has been fixed.
+
=head2 Formats
In addition to bug fixes, C<format>'s features have been enhanced. See
characters and groups to force a certain byte-order for that type or group.
See L<perlfunc/pack> and L<perlpacktut> for details.
+=head2 Byte count feature in pack()
+
+A new pack() template character, C<".">, returns the number of characters
+read so far.
+
=head2 New variables
A new variable, ${^RE_DEBUG_FLAGS}, controls what debug flags are in
=item *
+C<encoding::warnings>, by Autrijus Tang, is a module to emit warnings
+whenever an ASCII character string containing high-bit bytes is implicitly
+converted into UTF-8.
+
+=item *
+
C<Module::CoreList>, by Richard Clamp, is a small handy module that tells
you what versions of core modules ship with any versions of Perl 5. It
comes with a command-line frontend, C<corelist>.
=over 4
-=item *
-
=item B::Concise
C<B::Concise> was significantly improved.
=item *
-The C<corelist> utility is now installed with perl (see L</"New Modules">
+The C<corelist> utility is now installed with perl (see L</"New modules">
above).
=item *
=back
-=head1 Documentation
-
=head1 Performance Enhancements
=over 4
=item *
-Unnecessary assignment optimised away in
+Unnecessary assignments are optimised away in
my $s = undef;
my @a = ();
=item *
-Optimised C<map> in scalar context
+C<map> in scalar context is now optimized.
=item *
The regexp engine now implements the trie optimization : it's able to
factorize common prefixes and suffixes in regular expressions. A new
-special variable, ${^RE_TRIE_MAXBUF}, has been added to fine tune this
+special variable, ${^RE_TRIE_MAXBUF}, has been added to fine-tune this
optimization.
=back
=head1 Installation and Configuration Improvements
+Run-time customization of @INC can be enabled by passing the
+C<-Dusesitecustomize> flag to configure. When enabled, this will make perl
+run F<$sitelibexp/sitecustomize.pl> before anything else. This script can
+then be set up to add additional entries to @INC.
+
There is alpha support for relocatable @INC entries.
Perl should build on Interix and on GNU/kFreeBSD.
=head1 Selected Bug Fixes
-Most of those bugs were reported in the perl 5.8.x maintainance track.
+Most of those bugs were reported in the perl 5.8.x maintenance track.
Notably, quite a few utf8 bugs were fixed, and several memory leaks were
-suppressed.
+suppressed. The perl58Xdelta manpages have more details on them.
Development-only bug fixes include :
web browsers to wrap it, but might confuse any automatic tools which perform
detailed parsing of Carp output.
-Perl -V has several improvements, making it more useable from shell
-scripts.
+C<perl -V> has several improvements, making it more useable from shell
+scripts to get the value of configuration variables. See L<perlrun> for
+details.
=head1 Changed Internals
+The perl core has been refactored and reorganised in several places.
+In short, this release will not be binary compatible with any previous
+perl release.
+
=head1 Known Problems
-=head2 Platform Specific Problems
+For threaded builds, F<ext/threads/shared/t/wait.t> has been reported to
+fail some tests on HP-UX 10.20.
+
+F<t/io/dup.t> and F<t/io/open.t> fail some tests on some BSD flavours.
+
+=head1 Plans for the next release
+
+The current plan for perl 5.9.3 is to add CPANPLUS as a core module.
+More regular expression optimizations are also in the works.
+
+It is planned to release a development version of perl more frequently,
+i.e. each time something major changes.
=head1 Reporting Bugs