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PERL583DELTA(1)                       Perl Programmers Reference Guide                       PERL583DELTA(1)



NAME
       perl583delta - what is new for perl v5.8.3

DESCRIPTION
       This document describes differences between the 5.8.2 release and the 5.8.3 release.

       If you are upgrading from an earlier release such as 5.6.1, first read the perl58delta, which
       describes differences between 5.6.0 and 5.8.0, and the perl581delta and perl582delta, which describe
       differences between 5.8.0, 5.8.1 and 5.8.2

Incompatible Changes
       There are no changes incompatible with 5.8.2.

Core Enhancements
       A "SCALAR" method is now available for tied hashes. This is called when a tied hash is used in scalar
       context, such as

           if (%tied_hash) {
               ...
           }

       The old behaviour was that %tied_hash would return whatever would have been returned for that hash
       before the hash was tied (so usually 0). The new behaviour in the absence of a SCALAR method is to
       return TRUE if in the middle of an "each" iteration, and otherwise call FIRSTKEY to check if the hash
       is empty (making sure that a subsequent "each" will also begin by calling FIRSTKEY). Please see
       "SCALAR" in perltie for the full details and caveats.

Modules and Pragmata
       CGI
       Cwd
       Digest
       Digest::MD5
       Encode
       File::Spec
       FindBin
           A function "again" is provided to resolve problems where modules in different directories wish to
           use FindBin.

       List::Util
           You can now weaken references to read only values.

       Math::BigInt
       PodParser
       Pod::Perldoc
       POSIX
       Unicode::Collate
       Unicode::Normalize
       Test::Harness
       threads::shared
           "cond_wait" has a new two argument form. "cond_timedwait" has been added.

Utility Changes
       "find2perl" now assumes "-print" as a default action. Previously, it needed to be specified
       explicitly.

       A new utility, "prove", makes it easy to run an individual regression test at the command line.
       "prove" is part of Test::Harness, which users of earlier Perl versions can install from CPAN.

New Documentation
       The documentation has been revised in places to produce more standard manpages.

       The documentation for the special code blocks (BEGIN, CHECK, INIT, END) has been improved.

Installation and Configuration Improvements
       Perl now builds on OpenVMS I64

Selected Bug Fixes
       Using substr() on a UTF8 string could cause subsequent accesses on that string to return garbage.
       This was due to incorrect UTF8 offsets being cached, and is now fixed.

       join() could return garbage when the same join() statement was used to process 8 bit data having
       earlier processed UTF8 data, due to the flags on that statement's temporary workspace not being reset
       correctly. This is now fixed.

       "$a .. $b" will now work as expected when either $a or $b is "undef"

       Using Unicode keys with tied hashes should now work correctly.

       Reading $^E now preserves $!. Previously, the C code implementing $^E did not preserve "errno", so
       reading $^E could cause "errno" and therefore $! to change unexpectedly.

       Reentrant functions will (once more) work with C++. 5.8.2 introduced a bugfix which accidentally
       broke the compilation of Perl extensions written in C++

New or Changed Diagnostics
       The fatal error "DESTROY created new reference to dead object" is now documented in perldiag.

Changed Internals
       The hash code has been refactored to reduce source duplication. The external interface is unchanged,
       and aside from the bug fixes described above, there should be no change in behaviour.

       "hv_clear_placeholders" is now part of the perl API

       Some C macros have been tidied. In particular macros which create temporary local variables now name
       these variables more defensively, which should avoid bugs where names clash.

       <signal.h> is now always included.

Configuration and Building
       "Configure" now invokes callbacks regardless of the value of the variable they are called for.
       Previously callbacks were only invoked in the "case $variable $define)" branch. This change should
       only affect platform maintainers writing configuration hints files.

Platform Specific Problems
       The regression test ext/threads/shared/t/wait.t fails on early RedHat 9 and HP-UX 10.20 due to bugs
       in their threading implementations.  RedHat users should see
       https://rhn.redhat.com/errata/RHBA-2003-136.html and consider upgrading their glibc.

Known Problems
       Detached threads aren't supported on Windows yet, as they may lead to memory access violation
       problems.

       There is a known race condition opening scripts in "suidperl". "suidperl" is neither built nor
       installed by default, and has been deprecated since perl 5.8.0. You are advised to replace use of
       suidperl with tools such as sudo ( http://www.courtesan.com/sudo/ )

       We have a backlog of unresolved bugs. Dealing with bugs and bug reports is unglamorous work; not
       something ideally suited to volunteer labour, but that is all that we have.

       The perl5 development team are implementing changes to help address this problem, which should go
       live in early 2004.

Future Directions
       Code freeze for the next maintenance release (5.8.4) is on March 31st 2004, with release expected by
       mid April. Similarly 5.8.5's freeze will be at the end of June, with release by mid July.

Obituary
       Iain 'Spoon' Truskett, Perl hacker, author of perlreref and contributor to CPAN, died suddenly on
       29th December 2003, aged 24.  He will be missed.

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://bugs.perl.org.  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 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 "perl -V", will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
       You can browse and search the Perl 5 bugs at http://bugs.perl.org/

SEE ALSO
       The Changes file for exhaustive details on what changed.

       The INSTALL file for how to build Perl.

       The README file for general stuff.

       The Artistic and Copying files for copyright information.



perl v5.16.2                                     2012-08-26                                  PERL583DELTA(1)