perl583delta - what is new for perl v5.8.3


   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

       A function "again" is provided to resolve problems where modules in
       different directories wish to use FindBin.

       You can now weaken references to read only values.

       "cond_wait" has a new two argument form. "cond_timedwait" has been

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

   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 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 ( )

   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.


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

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  There may also be information at, 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 to be analysed by
   the Perl porting team.  You can browse and search the Perl 5 bugs at


   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.


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