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   1  =head1 NAME
   2  
   3  perl584delta - what is new for perl v5.8.4
   4  
   5  =head1 DESCRIPTION
   6  
   7  This document describes differences between the 5.8.3 release and
   8  the 5.8.4 release.
   9  
  10  =head1 Incompatible Changes
  11  
  12  Many minor bugs have been fixed. Scripts which happen to rely on previously
  13  erroneous behaviour will consider these fixes as incompatible changes :-)
  14  You are advised to perform sufficient acceptance testing on this release
  15  to satisfy yourself that this does not affect you, before putting this
  16  release into production.
  17  
  18  The diagnostic output of Carp has been changed slightly, to add a space after
  19  the comma between arguments. This makes it much easier for tools such as
  20  web browsers to wrap it, but might confuse any automatic tools which perform
  21  detailed parsing of Carp output.
  22  
  23  The internal dump output has been improved, so that non-printable characters
  24  such as newline and backspace are output in C<\x> notation, rather than
  25  octal. This might just confuse non-robust tools which parse the output of
  26  modules such as Devel::Peek.
  27  
  28  =head1 Core Enhancements
  29  
  30  =head2 Malloc wrapping
  31  
  32  Perl can now be built to detect attempts to assign pathologically large chunks
  33  of memory.  Previously such assignments would suffer from integer wrap-around
  34  during size calculations causing a misallocation, which would crash perl, and
  35  could theoretically be used for "stack smashing" attacks.  The wrapping
  36  defaults to enabled on platforms where we know it works (most AIX
  37  configurations, BSDi, Darwin, DEC OSF/1, FreeBSD, HP/UX, GNU Linux, OpenBSD,
  38  Solaris, VMS and most Win32 compilers) and defaults to disabled on other
  39  platforms.
  40  
  41  =head2 Unicode Character Database 4.0.1
  42  
  43  The copy of the Unicode Character Database included in Perl 5.8 has
  44  been updated to 4.0.1 from 4.0.0.
  45  
  46  =head2 suidperl less insecure
  47  
  48  Paul Szabo has analysed and patched C<suidperl> to remove existing known
  49  insecurities. Currently there are no known holes in C<suidperl>, but previous
  50  experience shows that we cannot be confident that these were the last. You may
  51  no longer invoke the set uid perl directly, so to preserve backwards
  52  compatibility with scripts that invoke #!/usr/bin/suidperl the only set uid
  53  binary is now C<sperl5.8.>I<n> (C<sperl5.8.4> for this release). C<suidperl>
  54  is installed as a hard link to C<perl>; both C<suidperl> and C<perl> will
  55  invoke C<sperl5.8.4> automatically the set uid binary, so this change should
  56  be completely transparent.
  57  
  58  For new projects the core perl team would strongly recommend that you use
  59  dedicated, single purpose security tools such as C<sudo> in preference to
  60  C<suidperl>.
  61  
  62  =head2 format
  63  
  64  In addition to bug fixes, C<format>'s features have been enhanced. See
  65  L<perlform>
  66  
  67  =head1 Modules and Pragmata
  68  
  69  The (mis)use of C</tmp> in core modules and documentation has been tidied up.
  70  Some modules available both within the perl core and independently from CPAN
  71  ("dual-life modules") have not yet had these changes applied; the changes
  72  will be integrated into future stable perl releases as the modules are
  73  updated on CPAN.
  74  
  75  =head2 Updated modules
  76  
  77  =over 4
  78  
  79  =item Attribute::Handlers
  80  
  81  =item B
  82  
  83  =item Benchmark
  84  
  85  =item CGI
  86  
  87  =item Carp
  88  
  89  =item Cwd
  90  
  91  =item Exporter
  92  
  93  =item File::Find
  94  
  95  =item IO
  96  
  97  =item IPC::Open3
  98  
  99  =item Local::Maketext
 100  
 101  =item Math::BigFloat
 102  
 103  =item Math::BigInt
 104  
 105  =item Math::BigRat
 106  
 107  =item MIME::Base64
 108  
 109  =item ODBM_File
 110  
 111  =item POSIX
 112  
 113  =item Shell
 114  
 115  =item Socket
 116  
 117  There is experimental support for Linux abstract Unix domain sockets.
 118  
 119  =item Storable
 120  
 121  =item Switch
 122  
 123  Synced with its CPAN version 2.10
 124  
 125  =item Sys::Syslog
 126  
 127  C<syslog()> can now use numeric constants for facility names and priorities,
 128  in addition to strings.
 129  
 130  =item Term::ANSIColor
 131  
 132  =item Time::HiRes
 133  
 134  =item Unicode::UCD
 135  
 136  =item Win32
 137  
 138  Win32.pm/Win32.xs has moved from the libwin32 module to core Perl
 139  
 140  =item base
 141  
 142  =item open
 143  
 144  =item threads
 145  
 146  Detached threads are now also supported on Windows.
 147  
 148  =item utf8
 149  
 150  =back
 151  
 152  =head1 Performance Enhancements
 153  
 154  =over 4
 155  
 156  =item *
 157  
 158  Accelerated Unicode case mappings (C</i>, C<lc>, C<uc>, etc).
 159  
 160  =item *
 161  
 162  In place sort optimised (eg C<@a = sort @a>)
 163  
 164  =item *
 165  
 166  Unnecessary assignment optimised away in
 167  
 168    my $s = undef;
 169    my @a = ();
 170    my %h = ();
 171  
 172  =item *
 173  
 174  Optimised C<map> in scalar context
 175  
 176  =back
 177  
 178  =head1 Utility Changes
 179  
 180  The Perl debugger (F<lib/perl5db.pl>) can now save all debugger commands for
 181  sourcing later, and can display the parent inheritance tree of a given class.
 182  
 183  =head1 Installation and Configuration Improvements
 184  
 185  The build process on both VMS and Windows has had several minor improvements
 186  made. On Windows Borland's C compiler can now compile perl with PerlIO and/or
 187  USE_LARGE_FILES enabled.
 188  
 189  C<perl.exe> on Windows now has a "Camel" logo icon. The use of a camel with
 190  the topic of Perl is a trademark of O'Reilly and Associates Inc., and is used
 191  with their permission (ie distribution of the source, compiling a Windows
 192  executable from it, and using that executable locally). Use of the supplied
 193  camel for anything other than a perl executable's icon is specifically not
 194  covered, and anyone wishing to redistribute perl binaries I<with> the icon
 195  should check directly with O'Reilly beforehand.
 196  
 197  Perl should build cleanly on Stratus VOS once more.
 198  
 199  =head1 Selected Bug Fixes
 200  
 201  More utf8 bugs fixed, notably in how C<chomp>, C<chop>, C<send>, and
 202  C<syswrite> and interact with utf8 data. Concatenation now works correctly
 203  when C<use bytes;> is in scope.
 204  
 205  Pragmata are now correctly propagated into (?{...}) constructions in regexps.
 206  Code such as
 207  
 208     my $x = qr{ ... (??{ $x }) ... };
 209  
 210  will now (correctly) fail under use strict. (As the inner C<$x> is and
 211  has always referred to C<$::x>)
 212  
 213  The "const in void context" warning has been suppressed for a constant in an
 214  optimised-away boolean expression such as C<5 || print;>
 215  
 216  C<perl -i> could C<fchmod(stdin)> by mistake. This is serious if stdin is
 217  attached to a terminal, and perl is running as root. Now fixed.
 218  
 219  =head1 New or Changed Diagnostics
 220  
 221  C<Carp> and the internal diagnostic routines used by C<Devel::Peek> have been
 222  made clearer, as described in L</Incompatible Changes>
 223  
 224  =head1 Changed Internals
 225  
 226  Some bugs have been fixed in the hash internals. Restricted hashes and
 227  their place holders are now allocated and deleted at slightly different times,
 228  but this should not be visible to user code.
 229  
 230  =head1 Future Directions
 231  
 232  Code freeze for the next maintenance release (5.8.5) will be on 30th June
 233  2004, with release by mid July.
 234  
 235  =head1 Platform Specific Problems
 236  
 237  This release is known not to build on Windows 95.
 238  
 239  =head1 Reporting Bugs
 240  
 241  If you find what you think is a bug, you might check the articles
 242  recently posted to the comp.lang.perl.misc newsgroup and the perl
 243  bug database at http://bugs.perl.org.  There may also be
 244  information at http://www.perl.org, the Perl Home Page.
 245  
 246  If you believe you have an unreported bug, please run the B<perlbug>
 247  program included with your release.  Be sure to trim your bug down
 248  to a tiny but sufficient test case.  Your bug report, along with the
 249  output of C<perl -V>, will be sent off to perlbug@perl.org to be
 250  analysed by the Perl porting team.  You can browse and search
 251  the Perl 5 bugs at http://bugs.perl.org/
 252  
 253  =head1 SEE ALSO
 254  
 255  The F<Changes> file for exhaustive details on what changed.
 256  
 257  The F<INSTALL> file for how to build Perl.
 258  
 259  The F<README> file for general stuff.
 260  
 261  The F<Artistic> and F<Copying> files for copyright information.
 262  
 263  =cut