Rephrase perlop for non-destructive substitution

[p5sagit/p5-mst-13.2.git] / pod / perl5130delta.pod

=encoding utf8

=head1 NAME

perldelta5130 - what is new for perl v5.13.0

=head1 DESCRIPTION

This document describes differences between the 5.12.0 release and the
5.13.0 release.

If you are upgrading from an earlier release such as 5.10.0, first read
L<perl5120delta>, which describes differences between 5.10.0 and
5.12.0.

=head1 Core Enhancements

=head2 "safe signals" optimization

Signal dispatch has been moved from the runloop into control ops. This
should give a few percent speed increase, and eliminates almost all of
the speed penalty caused by the introduction of "safe signals" in
5.8.0. Signals should still be dispatched within the same statement as
they were previously - if this is not the case, or it is possible to
create uninterruptable loops, this is a bug, and reports are encouraged
of how to recreate such issues.

=head2 Assignment to C<$0> sets the legacy process name with C<prctl()> on Linux

On Linux the legacy process name will be set with L<prctl(2)>, in
addition to altering the POSIX name via C<argv[0]> as perl has done
since version 4.000. Now system utilities that read the legacy process
name such as ps, top and killall will recognize the name you set when
assigning to C<$0>. The string you supply will be cut off at 16 bytes,
this is a limitation imposed by Linux.

=head2 Optimization of shift; and pop; calls without arguments

Additional two OPs are not added anymore into op tree for shift and pop
calls without argument (when it works on C<@_>). Makes C<shift;> 5%
faster over C<shift @_;> on not threaded perl and 25% faster on threaded.

=head1 Modules and Pragmata

=head2 Updated Modules

=over 4

=item CGI

Updated to version 3.49.

=item Data::Dumper

Updated to version 2.126.

=item MIME::Base64

Updated to 3.09.

=item threads

Updated to version 1.77

=item threads-shared

Updated to version 1.33

=back

=head1 Installation and Configuration Improvements

=head2 Platform Specific Changes

=over 4

=item AIX

Allow building on AIX 4.2.

=back

=head1 Acknowledgements

Perl 5.13.0 represents eight days of development since Perl 5.12.0 and
contains 3,766 lines of changes across 151 files from 29 authors and
committers.

Thank you to the following for contributing to this release:

Ævar Arnfjörð Bjarmason, Alex Vandiver, Chris Williams, chromatic,
Craig A. Berry, David Golden, David Mitchell, Eric Brine, Father
Chrysostomos, Florian Ragwitz, Frank Wiegand, Gisle Aas, H.Merijn
Brand, Hugo van der Sanden, Jesse Vincent, Josh ben Jore, Karl
Williamson, Leon Brocard, Michael G Schwern, Michael G. Schwern, Nga
Tang Chan, Nicholas Clark, Niko Tyni, Rafael Garcia-Suarez, Ricardo
Signes, Robin Barker, Slaven Rezic, Steffen Mueller, Zefram.

=head1 Reporting Bugs

If you find what you think is a bug, you might check the articles
recently posted to the comp.lang.perl.misc newsgroup and the perl bug
database at http://rt.perl.org/perlbug/ .  There may also be
information at http://www.perl.org/ , the Perl Home Page.

If you believe you have an unreported bug, please run the B<perlbug>
program included with your release.  Be sure to trim your bug down to a
tiny but sufficient test case.  Your bug report, along with the output
of C<perl -V>, will be sent off to perlbug@perl.org to be analysed by
the Perl porting team.

If the bug you are reporting has security implications, which make it
inappropriate to send to a publicly archived mailing list, then please
send it to perl5-security-report@perl.org. This points to a closed
subscription unarchived mailing list, which includes all the core
committers, who be able to help assess the impact of issues, figure out
a resolution, and help co-ordinate the release of patches to mitigate
or fix the problem across all platforms on which Perl is supported.
Please only use this address for security issues in the Perl core, not
for modules independently distributed on CPAN.

=head1 SEE ALSO

The F<Changes> file for an explanation of how to view exhaustive
details on what changed.

The F<INSTALL> file for how to build Perl.

The F<README> file for general stuff.

The F<Artistic> and F<Copying> files for copyright information.

=cut