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   1  =head1 NAME
   2  
   3  perl583delta - what is new for perl v5.8.3
   4  
   5  =head1 DESCRIPTION
   6  
   7  This document describes differences between the 5.8.2 release and
   8  the 5.8.3 release.
   9  
  10  If you are upgrading from an earlier release such as 5.6.1, first read
  11  the L<perl58delta>, which describes differences between 5.6.0 and
  12  5.8.0, and the L<perl581delta> and L<perl582delta>, which describe differences
  13  between 5.8.0, 5.8.1 and 5.8.2
  14  
  15  =head1 Incompatible Changes
  16  
  17  There are no changes incompatible with 5.8.2.
  18  
  19  =head1 Core Enhancements
  20  
  21  A C<SCALAR> method is now available for tied hashes. This is called when
  22  a tied hash is used in scalar context, such as
  23  
  24      if (%tied_hash) {
  25      ...
  26      }
  27  
  28  
  29  The old behaviour was that %tied_hash would return whatever would have been
  30  returned for that hash before the hash was tied (so usually 0). The new
  31  behaviour in the absence of a SCALAR method is to return TRUE if in the
  32  middle of an C<each> iteration, and otherwise call FIRSTKEY to check if the
  33  hash is empty (making sure that a subsequent C<each> will also begin by
  34  calling FIRSTKEY). Please see L<perltie/SCALAR> for the full details and
  35  caveats.
  36  
  37  =head1 Modules and Pragmata
  38  
  39  =over 4
  40  
  41  =item CGI
  42  
  43  =item Cwd
  44  
  45  =item Digest
  46  
  47  =item Digest::MD5
  48  
  49  =item Encode
  50  
  51  =item File::Spec
  52  
  53  =item FindBin
  54  
  55  A function C<again> is provided to resolve problems where modules in different
  56  directories wish to use FindBin.
  57  
  58  =item List::Util
  59  
  60  You can now weaken references to read only values.
  61  
  62  =item Math::BigInt
  63  
  64  =item PodParser
  65  
  66  =item Pod::Perldoc
  67  
  68  =item POSIX
  69  
  70  =item Unicode::Collate
  71  
  72  =item Unicode::Normalize
  73  
  74  =item Test::Harness
  75  
  76  =item threads::shared
  77  
  78  C<cond_wait> has a new two argument form. C<cond_timedwait> has been added.
  79  
  80  =back
  81  
  82  =head1 Utility Changes
  83  
  84  C<find2perl> now assumes C<-print> as a default action. Previously, it
  85  needed to be specified explicitly.
  86  
  87  A new utility, C<prove>, makes it easy to run an individual regression test
  88  at the command line. C<prove> is part of Test::Harness, which users of earlier
  89  Perl versions can install from CPAN.
  90  
  91  =head1 New Documentation
  92  
  93  The documentation has been revised in places to produce more standard manpages.
  94  
  95  The documentation for the special code blocks (BEGIN, CHECK, INIT, END)
  96  has been improved.
  97  
  98  =head1 Installation and Configuration Improvements
  99  
 100  Perl now builds on OpenVMS I64
 101  
 102  =head1 Selected Bug Fixes
 103  
 104  Using substr() on a UTF8 string could cause subsequent accesses on that
 105  string to return garbage. This was due to incorrect UTF8 offsets being
 106  cached, and is now fixed.
 107  
 108  join() could return garbage when the same join() statement was used to
 109  process 8 bit data having earlier processed UTF8 data, due to the flags
 110  on that statement's temporary workspace not being reset correctly. This
 111  is now fixed.
 112  
 113  C<$a .. $b> will now work as expected when either $a or $b is C<undef>
 114  
 115  Using Unicode keys with tied hashes should now work correctly.
 116  
 117  Reading $^E now preserves $!. Previously, the C code implementing $^E
 118  did not preserve C<errno>, so reading $^E could cause C<errno> and therefore
 119  C<$!> to change unexpectedly.
 120  
 121  Reentrant functions will (once more) work with C++. 5.8.2 introduced a bugfix
 122  which accidentally broke the compilation of Perl extensions written in C++
 123  
 124  =head1 New or Changed Diagnostics
 125  
 126  The fatal error "DESTROY created new reference to dead object" is now
 127  documented in L<perldiag>.
 128  
 129  =head1 Changed Internals
 130  
 131  The hash code has been refactored to reduce source duplication. The
 132  external interface is unchanged, and aside from the bug fixes described
 133  above, there should be no change in behaviour.
 134  
 135  C<hv_clear_placeholders> is now part of the perl API
 136  
 137  Some C macros have been tidied. In particular macros which create temporary
 138  local variables now name these variables more defensively, which should
 139  avoid bugs where names clash.
 140  
 141  <signal.h> is now always included.
 142  
 143  =head1 Configuration and Building
 144  
 145  C<Configure> now invokes callbacks regardless of the value of the variable
 146  they are called for. Previously callbacks were only invoked in the
 147  C<case $variable $define)> branch. This change should only affect platform
 148  maintainers writing configuration hints files.
 149  
 150  =head1 Platform Specific Problems
 151  
 152  The regression test ext/threads/shared/t/wait.t fails on early RedHat 9
 153  and HP-UX 10.20 due to bugs in their threading implementations.
 154  RedHat users should see https://rhn.redhat.com/errata/RHBA-2003-136.html
 155  and consider upgrading their glibc.
 156  
 157  =head1 Known Problems
 158  
 159  Detached threads aren't supported on Windows yet, as they may lead to 
 160  memory access violation problems.
 161  
 162  There is a known race condition opening scripts in C<suidperl>. C<suidperl>
 163  is neither built nor installed by default, and has been deprecated since
 164  perl 5.8.0. You are advised to replace use of suidperl with tools such
 165  as sudo ( http://www.courtesan.com/sudo/ )
 166  
 167  We have a backlog of unresolved bugs. Dealing with bugs and bug reports
 168  is unglamorous work; not something ideally suited to volunteer labour,
 169  but that is all that we have.
 170  
 171  The perl5 development team are implementing changes to help address this
 172  problem, which should go live in early 2004.
 173  
 174  =head1 Future Directions
 175  
 176  Code freeze for the next maintenance release (5.8.4) is on March 31st 2004,
 177  with release expected by mid April. Similarly 5.8.5's freeze will be at
 178  the end of June, with release by mid July.
 179  
 180  =head1 Obituary
 181  
 182  Iain 'Spoon' Truskett, Perl hacker, author of L<perlreref> and
 183  contributor to CPAN, died suddenly on 29th December 2003, aged 24.
 184  He will be missed.
 185  
 186  =head1 Reporting Bugs
 187  
 188  If you find what you think is a bug, you might check the articles
 189  recently posted to the comp.lang.perl.misc newsgroup and the perl
 190  bug database at http://bugs.perl.org.  There may also be
 191  information at http://www.perl.org, the Perl Home Page.
 192  
 193  If you believe you have an unreported bug, please run the B<perlbug>
 194  program included with your release.  Be sure to trim your bug down
 195  to a tiny but sufficient test case.  Your bug report, along with the
 196  output of C<perl -V>, will be sent off to perlbug@perl.org to be
 197  analysed by the Perl porting team.  You can browse and search
 198  the Perl 5 bugs at http://bugs.perl.org/
 199  
 200  =head1 SEE ALSO
 201  
 202  The F<Changes> file for exhaustive details on what changed.
 203  
 204  The F<INSTALL> file for how to build Perl.
 205  
 206  The F<README> file for general stuff.
 207  
 208  The F<Artistic> and F<Copying> files for copyright information.
 209  
 210  =cut