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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 [email protected] to be
analysed by the Perl porting team. You can browse and search the Perl 5 bugs at
http://bugs.perl.org/

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