=head1 DESCRIPTION
-This document describes differences between the 5.6.0 release and the
-5.8.0 release.
+This document describes differences between the 5.6.0 release
+and the 5.8.0 release.
-=head1 Security Vulnerability Closed
-
-A potential security vulnerability in the optional suidperl component
-of Perl has been identified. suidperl is neither built nor installed
-by default. As of September the 2nd, 2000, the only known vulnerable
-platform is Linux, most likely all Linux distributions. CERT and
-various vendors have been alerted about the vulnerability.
-
-The problem was caused by Perl trying to report a suspected security
-exploit attempt using an external program, /bin/mail. On Linux
-platforms the /bin/mail program had an undocumented feature which
-when combined with suidperl gave access to a root shell, resulting in
-a serious compromise instead of reporting the exploit attempt. If you
-don't have /bin/mail, or if you have 'safe setuid scripts', or if
-suidperl is not installed, you are safe.
+Many of the bug fixes in 5.8.0 were already seen in the 5.6.1
+maintenance release since the two releases were kept closely
+coordinated.
-The exploit attempt reporting feature has been completely removed from
-the Perl 5.7.0 release, so that particular vulnerability isn't there
-anymore. However, further security vulnerabilities are,
-unfortunately, always possible. The suidperl code is being reviewed
-and if deemed too risky to continue to be supported, it may be
-completely removed from future releases. In any case, suidperl should
-only be used by security experts who know exactly what they are doing
-and why they are using suidperl instead of some other solution such as
-sudo (see http://www.courtesan.com/sudo/).
+If you are upgrading from Perl 5.005_03, you might also want
+to read L<perl56delta>.
-=head1 Incompatible Changes
+=head1 Highlights In 5.8.0
=over 4
=item *
-Arrays now always interpolate into double-quoted strings:
-constructs like "foo@bar" now always assume C<@bar> is an array,
-whether or not the compiler has seen use of C<@bar>.
+Better Unicode support
=item *
-The semantics of bless(REF, REF) were unclear and until someone proves
-it to make some sense, it is forbidden.
+New Thread Implementation
=item *
-A reference to a reference now stringify as "REF(0x81485ec)" instead
-of "SCALAR(0x81485ec)" in order to be more consistent with the return
-value of ref().
+Many New Modules
=item *
-The very dusty examples in the eg/ directory have been removed.
-Suggestions for new shiny examples welcome but the main issue is that
-the examples need to be documented, tested and (most importantly)
-maintained.
+Better Numeric Accuracy
=item *
-The obsolete chat2 library that should never have been allowed
-to escape the laboratory has been decommissioned.
+Safe Signals
=item *
-The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
-recognised but now cause fatal errors. The previous behaviour of
-ignoring them by default and warning if requested was unacceptable
-since it, in a way, falsely promised that the features could be used.
+More Extensive Regression Testing
-=item *
+=back
-The (bogus) escape sequences \8 and \9 now give an optional warning
-("Unrecognized escape passed through"). There is no need to \-escape
-any C<\w> character.
+=head1 Incompatible Changes
-=item *
+=head2 64-bit platforms and malloc
-lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
-In future releases this may become a fatal error.
+If your pointers are 64 bits wide, the Perl malloc is no longer being
+used because it does not work well with 8-byte pointers. Also,
+usually the system mallocs on such platforms are much better optimized
+for such large memory models than the Perl malloc. Some memory-hungry
+Perl applications like the PDL don't work well with Perl's malloc.
+Finally, other applications than Perl (like modperl) tend to prefer
+the system malloc. Such platforms include Alpha and 64-bit HPPA,
+MIPS, PPC, and Sparc.
-=item *
+=head2 AIX Dynaloading
-The long deprecated uppercase aliases for the string comparison
-operators (EQ, NE, LT, LE, GE, GT) have now been removed.
+The AIX dynaloading now uses in AIX releases 4.3 and newer the native
+dlopen interface of AIX instead of the old emulated interface. This
+change will probably break backward compatibility with compiled
+modules. The change was made to make Perl more compliant with other
+applications like modperl which are using the AIX native interface.
-=item *
+=head2 Attributes for C<my> variables now handled at run-time.
-The regular expression captured submatches ($1, $2, ...) are now
-more consistently unset if the match fails, instead of leaving false
-data lying around in them.
+The C<my EXPR : ATTRS> syntax now applies variable attributes at
+run-time. (Subroutine and C<our> variables still get attributes applied
+at compile-time.) See L<attributes> for additional details. In particular,
+however, this allows variable attributes to be useful for C<tie> interfaces,
+which was a deficiency of earlier releases. Note that the new semantics
+doesn't work with the Attribute::Handlers module (as of version 0.76).
-=item *
+=head2 Socket Extension Dynamic in VMS
-The tr///C and tr///U features have been removed and will not return;
-the interface was a mistake. Sorry about that. For similar
-functionality, see pack('U0', ...) and pack('C0', ...).
+The Socket extension is now dynamically loaded instead of being
+statically built in. This may or may not be a problem with ancient
+TCP/IP stacks of VMS: we do not know since we weren't able to test
+Perl in such configurations.
-=back
+=head2 IEEE-format Floating Point Default on OpenVMS Alpha
-=head1 Core Enhancements
+Perl now uses IEEE format (T_FLOAT) as the default internal floating
+point format on OpenVMS Alpha, potentially breaking binary compatibility
+with external libraries or existing data. G_FLOAT is still available as
+a configuration option. The default on VAX (D_FLOAT) has not changed.
-=over 4
+=head2 Different Definition of the Unicode Character Classes \p{In...}
-=item *
+As suggested by the Unicode consortium, the Unicode character classes
+now prefer I<scripts> as opposed to I<blocks> (as defined by Unicode);
+in Perl, when the C<\p{In....}> and the C<\p{In....}> regular expression
+constructs are used. This has changed the definition of some of those
+character classes.
-C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
-in multiple arguments.)
+The difference between scripts and blocks is that scripts are the
+glyphs used by a language or a group of languages, while the blocks
+are more artificial groupings of 256 characters based on the Unicode
+numbering.
-=item *
+In general this change results in more inclusive Unicode character
+classes, but changes to the other direction also do take place:
+for example while the script C<Latin> includes all the Latin
+characters and their various diacritic-adorned versions, it
+does not include the various punctuation or digits (since they
+are not solely C<Latin>).
-my __PACKAGE__ $obj now works.
+Changes in the character class semantics may have happened if a script
+and a block happen to have the same name, for example C<Hebrew>.
+In such cases the script wins and C<\p{InHebrew}> now means the script
+definition of Hebrew. The block definition in still available,
+though, by appending C<Block> to the name: C<\p{InHebrewBlock}> means
+what C<\p{InHebrew}> meant in perl 5.6.0. For the full list
+of affected character classes, see L<perlunicode/Blocks>.
-=item *
+=head2 Perl Parser Stress Tested
-C<no Module;> now works even if there is no "sub unimport" in the Module.
+The Perl parser has been stress tested using both random input and
+Markov chain input and the few found crashes and lockups have been
+fixed.
-=item *
+=head2 REF(...) Instead Of SCALAR(...)
-The numerical comparison operators return C<undef> if either operand
-is a NaN. Previously the behaviour was unspecified.
+A reference to a reference now stringifies as "REF(0x81485ec)" instead
+of "SCALAR(0x81485ec)" in order to be more consistent with the return
+value of ref().
-=item *
+=head2 Deprecations
-C<pack('U0a*', ...)> can now be used to force a string to UTF8.
+=over 4
=item *
-prototype(\&) is now available.
+The semantics of bless(REF, REF) were unclear and until someone proves
+it to make some sense, it is forbidden.
=item *
-There is now an UNTIE method.
-
-=back
-
-=head1 Modules and Pragmata
-
-=head2 New Modules
-
-=over 4
+The obsolete chat2 library that should never have been allowed
+to escape the laboratory has been decommissioned.
=item *
-File::Temp allows one to create temporary files and directories in an
-easy, portable, and secure way.
+The very dusty examples in the eg/ directory have been removed.
+Suggestions for new shiny examples welcome but the main issue is that
+the examples need to be documented, tested and (most importantly)
+maintained.
=item *
-Storable gives persistence to Perl data structures by allowing the
-storage and retrieval of Perl data to and from files in a fast and
-compact binary format.
-
-=back
-
-=head2 Updated And Improved Modules and Pragmata
-
-=over 4
+The (bogus) escape sequences \8 and \9 now give an optional warning
+("Unrecognized escape passed through"). There is no need to \-escape
+any C<\w> character.
=item *
-The following independently supported modules have been updated to
-newer versions from CPAN: CGI, CPAN, DB_File, File::Spec, Getopt::Long,
-the podlators bundle, Pod::LaTeX, Pod::Parser, Term::ANSIColor, Test.
+The list of filenames from glob() (or <...>) is now by default sorted
+alphabetically to be csh-compliant (which is what happened before
+in most UNIX platforms). (bsd_glob() does still sort platform
+natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
=item *
-Bug fixes and minor enhancements have been applied to B::Deparse,
-Data::Dumper, IO::Poll, IO::Socket::INET, Math::BigFloat,
-Math::Complex, Math::Trig, Net::protoent, the re pragma, SelfLoader,
-Sys::SysLog, Test::Harness, Text::Wrap, UNIVERSAL, and the warnings
-pragma.
+Spurious syntax errors generated in certain situations, when glob()
+caused File::Glob to be loaded for the first time, have been fixed.
=item *
-The attributes::reftype() now works on tied arguments.
+Although "you shouldn't do that", it was possible to write code that
+depends on Perl's hashed key order (Data::Dumper does this). The new
+algorithm "One-at-a-Time" produces a different hashed key order.
+More details are in L</"Performance Enhancements">.
=item *
-AutoLoader can now be disabled with C<no AutoLoader;>,
+lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
+In future releases this may become a fatal error.
=item *
-The English module can now be used without the infamous performance
-hit by saying
-
- use English '-no_performance_hit';
-
-(Assuming, of course, that one doesn't need the troublesome variables
-C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
-C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
+The C<package;> syntax (C<package> without an argument) has been
+deprecated. Its semantics were never that clear and its
+implementation even less so. If you have used that feature to
+disallow all but fully qualified variables, C<use strict;> instead.
=item *
-File::Find now has pre- and post-processing callbacks. It also
-correctly changes directories when chasing symbolic links. Callbacks
-(naughtily) exiting with "next;" instead of "return;" now work.
+The unimplemented POSIX regex features [[.cc.]] and [[=c=]] are still
+recognised but now cause fatal errors. The previous behaviour of
+ignoring them by default and warning if requested was unacceptable
+since it, in a way, falsely promised that the features could be used.
=item *
-File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
-prototype mismatch with CORE::glob().
+The current user-visible implementation of pseudo-hashes (the weird
+use of the first array element) is deprecated starting from Perl 5.8.0
+and will be removed in Perl 5.10.0, and the feature will be
+implemented differently. Not only is the current interface rather
+ugly, but the current implementation slows down normal array and hash
+use quite noticeably. The C<fields> pragma interface will remain
+available.
=item *
-IPC::Open3 now allows the use of numeric file descriptors.
+The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
=item *
-use lib now works identically to @INC. Removing directories
-with 'no lib' now works.
+After years of trying the suidperl is considered to be too complex to
+ever be considered truly secure. The suidperl functionality is likely
+to be removed in a future release.
=item *
-C<%INC> now localised in a Safe compartment so that use/require work.
+The long deprecated uppercase aliases for the string comparison
+operators (EQ, NE, LT, LE, GE, GT) have now been removed.
=item *
-The Shell module now has an OO interface.
+The tr///C and tr///U features have been removed and will not return;
+the interface was a mistake. Sorry about that. For similar
+functionality, see pack('U0', ...) and pack('C0', ...).
=back
-=head1 Utility Changes
-
-=over 4
+=head1 Core Enhancements
-=item *
+=head2 PerlIO is Now The Default
-The Emacs perl mode (emacs/cperl-mode.el) has been updated to version
-4.31.
+=over 4
=item *
-Perlbug is now much more robust. It also sends the bug report to
-perl.org, not perl.com.
-
-=item *
+IO is now by default done via PerlIO rather than system's "stdio".
+PerlIO allows "layers" to be "pushed" onto a file handle to alter the
+handle's behaviour. Layers can be specified at open time via 3-arg
+form of open:
-The perlcc utility has been rewritten and its user interface (that is,
-command line) is much more like that of the UNIX C compiler, cc.
+ open($fh,'>:crlf :utf8', $path) || ...
-=item *
+or on already opened handles via extended C<binmode>:
-The xsubpp utility for extension writers now understands POD
-documentation embedded in the *.xs files.
+ binmode($fh,':encoding(iso-8859-7)');
-=back
+The built-in layers are: unix (low level read/write), stdio (as in
+previous Perls), perlio (re-implementation of stdio buffering in a
+portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
+but available on any platform). A mmap layer may be available if
+platform supports it (mostly UNIXes).
-=head1 New Documentation
+Layers to be applied by default may be specified via the 'open' pragma.
-=over 4
+See L</"Installation and Configuration Improvements"> for the effects
+of PerlIO on your architecture name.
=item *
-perl56delta details the changes between the 5.005 release and the
-5.6.0 release.
+File handles can be marked as accepting Perl's internal encoding of Unicode
+(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
-=item *
+ open($fh,">:utf8","Uni.txt");
-perldebtut is a Perl debugging tutorial.
+Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
+for you since it's not UTF-8 what you will be getting but instead
+UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
+http://www.unicode.org/unicode/reports/tr16/ for more information.
+In future releases this naming may change.
=item *
-perlebcdic contains considerations for running Perl on EBCDIC platforms.
-Note that unfortunately EBCDIC platforms that used to supported back in
-Perl 5.005 are still unsupported by Perl 5.7.0; the plan, however, is to
-bring them back to the fold.
+File handles can translate character encodings from/to Perl's internal
+Unicode form on read/write via the ":encoding()" layer.
=item *
-perlnewmod tells about writing and submitting a new module.
-
-=item *
+File handles can be opened to "in memory" files held in Perl scalars via:
-perlposix-bc explains using Perl on the POSIX-BC platform
-(an EBCDIC mainframe platform).
+ open($fh,'>', \$variable) || ...
=item *
-perlretut is a regular expression tutorial.
+Anonymous temporary files are available without need to
+'use FileHandle' or other module via
-=item *
+ open($fh,"+>", undef) || ...
-perlrequick is a regular expressions quick-start guide.
-Yes, much quicker than perlretut.
+That is a literal undef, not an undefined value.
=item *
-perlutil explains the command line utilities packaged with the Perl
-distribution.
-
-=back
-
-=head1 Performance Enhancements
+The list form of C<open> is now implemented for pipes (at least on UNIX):
-=over 4
+ open($fh,"-|", 'cat', '/etc/motd')
-=item *
+creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
+the child process.
-map() that changes the size of the list should now work faster.
+=back
-=item *
+=head2 Safe Signals
-sort() has been changed to use mergesort internally as opposed to the
-earlier quicksort. For very small lists this may result in slightly
-slower sorting times, but in general the speedup should be at least
-20%. Additional bonuses are that the worst case behaviour of sort()
-is now better (in computer science terms it now runs in time O(N log N),
-as opposed to quicksort's Theta(N**2) worst-case run time behaviour),
-and that sort() is now stable (meaning that elements with identical
-keys will stay ordered as they were before the sort).
+Perl used to be fragile in that signals arriving at inopportune moments
+could corrupt Perl's internal state. Now Perl postpones handling of
+signals until it's safe (between opcodes).
-=back
+This change may have surprising side effects because signals no more
+interrupt Perl instantly. Perl will now first finish whatever it was
+doing, like finishing an internal operation (like sort()) or an
+external operation (like an I/O operation), and only then look at any
+arrived signals (and before starting the next operation). No more corrupt
+internal state since the current operation is always finished first,
+but the signal may take more time to get heard.
-=head1 Installation and Configuration Improvements
+=head2 Unicode Overhaul
-=head2 Generic Improvements
+Unicode in general should be now much more usable than in Perl 5.6.0
+(or even in 5.6.1). Unicode can be used in hash keys, Unicode in
+regular expressions should work now, Unicode in tr/// should work now,
+Unicode in I/O should work now.
=over 4
=item *
-INSTALL now explains how you can configure Perl to use 64-bit
-integers even on non-64-bit platforms.
+The Unicode Character Database coming with Perl has been upgraded
+to Unicode 3.1.1. For more information, see http://www.unicode.org/.
=item *
-Policy.sh policy change: if you are reusing a Policy.sh file
-(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
-Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
-them will now be changed to the new prefix, /foo/bar. (Previously
-only $prefix changed.) If you do not like this new behaviour,
-specify prefix, siteprefix, and vendorprefix explicitly.
-
-=item *
-
-A new optional location for Perl libraries, otherlibdirs, is available.
-It can be used for example for vendor add-ons without disturbing Perl's
-own library directories.
+For developers interested in enhancing Perl's Unicode capabilities:
+almost all the UCD files are included with the Perl distribution in
+the lib/unicore subdirectory. The most notable omission, for space
+considerations, is the Unihan database.
=item *
-In many platforms the vendor-supplied 'cc' is too stripped-down to
-build Perl (basically, 'cc' doesn't do ANSI C). If this seems
-to be the case and 'cc' does not seem to be the GNU C compiler
-'gcc', an automatic attempt is made to find and use 'gcc' instead.
+The Unicode character classes \p{Blank} and \p{SpacePerl} have been
+added. "Blank" is like C isblank(), that is, it contains only
+"horizontal whitespace" (the space character is, the newline isn't),
+and the "SpacePerl" is the Unicode equivalent of C<\s> (\p{Space}
+isn't, since that includes the vertical tabulator character, whereas
+C<\s> doesn't.)
-=item *
+=back
-gcc needs to closely track the operating system release to avoid
-build problems. If Configure finds that gcc was built for a different
-operating system release than is running, it now gives a clearly visible
-warning that there may be trouble ahead.
+=head2 Understanding of Numbers
-=item *
+In general a lot of fixing has happened in the area of Perl's
+understanding of numbers, both integer and floating point. Since in
+many systems the standard number parsing functions like C<strtoul()>
+and C<atof()> seem to have bugs, Perl tries to work around their
+deficiencies. This results hopefully in more accurate numbers.
-If binary compatibility with the 5.005 release is not wanted, Configure
-no longer suggests including the 5.005 modules in @INC.
+Perl now tries internally to use integer values in numeric conversions
+and basic arithmetics (+ - * /) if the arguments are integers, and
+tries also to keep the results stored internally as integers.
+This change leads to often slightly faster and always less lossy
+arithmetics. (Previously Perl always preferred floating point numbers
+in its math.)
-=item *
+=head2 Miscellaneous Enhancements
-Configure C<-S> can now run non-interactively.
+=over 4
=item *
-configure.gnu now works with options with whitespace in them.
+AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
+to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
=item *
-installperl now outputs everything to STDERR.
+C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
+in multiple arguments.)
=item *
-$Config{byteorder} is now computed dynamically (this is more robust
-with "fat binaries" where an executable image contains binaries for
-more than one binary platform.)
-
-=back
-
-=head1 Selected Bug Fixes
-
-=over 4
+END blocks are now run even if you exit/die in a BEGIN block.
+Internally, the execution of END blocks is now controlled by
+PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
+behaviour for Perl embedders. This will default in 5.10. See
+L<perlembed>.
=item *
-Several debugger fixes: exit code now reflects the script exit code,
-condition C<"0"> now treated correctly, the C<d> command now checks
-line number, the C<$.> no longer gets corrupted, all debugger output now
-goes correctly to the socket if RemotePort is set.
+Formats now support zero-padded decimal fields.
=item *
-C<*foo{FORMAT}> now works.
+Lvalue subroutines can now return C<undef> in list context.
+However, the lvalue subroutine feature still remains experimental.
=item *
-Lexical warnings now propagating correctly between scopes.
+A new special regular expression variable has been introduced:
+C<$^N>, which contains the most-recently closed group (submatch).
=item *
-Line renumbering with eval and C<#line> now works.
+C<no Module;> now works even if there is no "sub unimport" in the Module.
=item *
-Fixed numerous memory leaks, especially in eval "".
+The numerical comparison operators return C<undef> if either operand
+is a NaN. Previously the behaviour was unspecified.
=item *
-Modulus of unsigned numbers now works (4063328477 % 65535 used to
-return 27406, instead of 27047).
+The following builtin functions are now overridable: each(), keys(),
+pop(), push(), shift(), splice(), unshift().
=item *
-Some "not a number" warnings introduced in 5.6.0 eliminated to be
-more compatible with 5.005. Infinity is now recognised as a number.
+C<pack('U0a*', ...)> can now be used to force a string to UTF8.
=item *
-our() variables will not cause "will not stay shared" warnings.
+my __PACKAGE__ $obj now works.
=item *
-pack "Z" now correctly terminates the string with "\0".
+The printf() and sprintf() now support parameter reordering using the
+C<%\d+\$> and C<*\d+\$> syntaxes. For example
-=item *
+ print "%2\$s %1\$s\n", "foo", "bar";
-Fix password routines which in some shadow password platforms
-(e.g. HP-UX) caused getpwent() to return every other entry.
+will print "bar foo\n". This feature helps in writing
+internationalised software, and in general when the order
+of the parameters can vary.
=item *
-printf() no longer resets the numeric locale to "C".
+prototype(\&) is now available.
=item *
-C<q(a\\b)> now parses correctly as C<'a\\b'>.
+prototype(\[$@%&]) is now available to implicitly create references
+(useful for example if you want to emulate the tie() interface).
=item *
-Printing quads (64-bit integers) with printf/sprintf now works
-without the q L ll prefixes (assuming you are on a quad-capable platform).
+untie() will now call an UNTIE() hook if it exists. See L<perltie>
+for details.
=item *
-Regular expressions on references and overloaded scalars now work.
+L<utime> now supports C<utime undef, undef, @files> to change the
+file timestamps to the current time.
=item *
-scalar() now forces scalar context even when used in void context.
+The rules for allowing underscores (underbars) in numeric constants
+have been relaxed and simplified: now you can have an underscore
+simply B<between digits>.
-=item *
+=back
-sort() arguments are now compiled in the right wantarray context
-(they were accidentally using the context of the sort() itself).
+=head1 Modules and Pragmata
-=item *
+=head2 New Modules and Pragmata
-Changed the POSIX character class C<[[:space:]]> to include the (very
-rare) vertical tab character. Added a new POSIX-ish character class
-C<[[:blank:]]> which stands for horizontal whitespace (currently,
-the space and the tab).
+=over 4
=item *
-$AUTOLOAD, sort(), lock(), and spawning subprocesses
-in multiple threads simultaneously are now thread-safe.
-
-=item *
+C<Attribute::Handlers> allows a class to define attribute handlers.
-Allow read-only string on left hand side of non-modifying tr///.
+ package MyPack;
+ use Attribute::Handlers;
+ sub Wolf :ATTR(SCALAR) { print "howl!\n" }
-=item *
+ # later, in some package using or inheriting from MyPack...
-Several Unicode fixes (but still not perfect).
+ my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
-=over 8
+Both variables and routines can have attribute handlers. Handlers can
+be specific to type (SCALAR, ARRAY, HASH, or CODE), or specific to the
+exact compilation phase (BEGIN, CHECK, INIT, or END).
=item *
-BOMs (byte order marks) in the beginning of Perl files
-(scripts, modules) should now be transparently skipped.
-UTF-16 (UCS-2) encoded Perl files should now be read correctly.
+B<B::Concise> is a new compiler backend for walking the Perl syntax
+tree, printing concise info about ops, from Stephen McCamant. The
+output is highly customisable. See L<B::Concise>.
=item *
-The character tables have been updated to Unicode 3.0.1.
+C<Class::ISA> for reporting the search path for a class's ISA tree,
+by Sean Burke, has been added. See L<Class::ISA>.
=item *
-chr() for values greater than 127 now create utf8 when under use
-utf8.
+C<Cwd> has now a split personality: if possible, an XS extension is
+used, (this will hopefully be faster, more secure, and more robust)
+but if not possible, the familiar Perl implementation is used.
=item *
-Comparing with utf8 data does not magically upgrade non-utf8 data into
-utf8.
+C<Devel::PPPort>, originally from Kenneth Albanowski and now
+maintained by Paul Marquess, has been added. It is primarily used
+by C<h2xs> to enhance portability of of XS modules between different
+versions of Perl.
=item *
-C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
+C<Digest>, frontend module for calculating digests (checksums), from
+Gisle Aas, has been added. See L<Digest>.
=item *
-Concatenation with the C<.> operator or via variable interpolation,
-C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
-substitution with C<s///>, single-quoted UTF8, should now work--in
-theory.
+C<Digest::MD5> for calculating MD5 digests (checksums) as defined in
+RFC 1321, from Gisle Aas, has been added. See L<Digest::MD5>.
-=item *
+ use Digest::MD5 'md5_hex';
-The C<tr///> operator now works I<slightly> better but is still rather
-broken. Note that the C<tr///CU> functionality has been removed (but
-see pack('U0', ...)).
+ $digest = md5_hex("Thirsty Camel");
-=item *
+ print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
-vec() now refuses to deal with characters >255.
+NOTE: the C<MD5> backward compatibility module is deliberately not
+included since its further use is discouraged.
=item *
-Zero entries were missing from the Unicode classes like C<IsDigit>.
+C<Encode>, by Nick Ing-Simmons, provides a mechanism to translate
+between different character encodings. Support for Unicode,
+ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
+compiled in to the module. Several other encodings (like Japanese,
+Chinese, and MacIntosh encodings) are included and will be loaded at
+runtime. See L<Encode>.
-=back
+Any encoding supported by Encode module is also available to the
+":encoding()" layer if PerlIO is used.
=item *
-UNIVERSAL::isa no longer caches methods incorrectly. (This broke
-the Tk extension with 5.6.0.)
-
-=back
+C<I18N::Langinfo> can be use to query locale information.
+See L<I18N::Langinfo>.
-=head2 Platform Specific Changes and Fixes
+=item *
-=over 4
+C<I18N::LangTags> has functions for dealing with RFC3066-style
+language tags, by Sean Burke. See L<I18N::LangTags>.
=item *
-BSDI 4.*
-
-Perl now works on post-4.0 BSD/OSes.
+C<ExtUtils::Constant> is a new tool for extension writers for
+generating XS code to import C header constants, by Nicholas Clark.
+See L<ExtUtils::Constant>.
=item *
-All BSDs
-
-Setting C<$0> now works (as much as possible; see perlvar for details).
+C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
+from Damian Conway. See L<Filter::Simple>.
-=item *
+ # in MyFilter.pm:
-Cygwin
+ package MyFilter;
-Numerous updates; currently synchronised with Cygwin 1.1.4.
+ use Filter::Simple sub {
+ while (my ($from, $to) = splice @_, 0, 2) {
+ s/$from/$to/g;
+ }
+ };
-=item *
+ 1;
-EPOC
+ # in user's code:
-EPOC update after Perl 5.6.0. See README.epoc.
+ use MyFilter qr/red/ => 'green';
-=item *
+ print "red\n"; # this code is filtered, will print "green\n"
+ print "bored\n"; # this code is filtered, will print "bogreen\n"
-FreeBSD 3.*
+ no MyFilter;
-Perl now works on post-3.0 FreeBSDs.
+ print "red\n"; # this code is not filtered, will print "red\n"
=item *
-HP-UX
-
-README.hpux updated; C<Configure -Duse64bitall> now almost works.
+C<File::Temp> allows one to create temporary files and directories in
+an easy, portable, and secure way, by Tim Jenness. See L<File::Temp>.
=item *
-IRIX
-
-Numerous compilation flag and hint enhancements; accidental mixing
-of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
+C<Filter::Util::Call> provides you with the framework to write
+I<Source Filters> in Perl, from Paul Marquess. For most uses the
+frontend Filter::Simple is to be preferred. See L<Filter::Util::Call>.
=item *
-Linux
+L<libnet> is a collection of perl5 modules related to network
+programming, from Graham Barr. See L<Net::FTP>, L<Net::NNTP>,
+L<Net::Ping>, L<Net::POP3>, L<Net::SMTP>, and L<Net::Time>.
-Long doubles should now work (see INSTALL).
+Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
=item *
-MacOS Classic
-
-Compilation of the standard Perl distribution in MacOS Classic should
-now work if you have the Metrowerks development environment and
-the missing Mac-specific toolkit bits. Contact the macperl mailing
-list for details.
+C<List::Util> is a selection of general-utility list subroutines, like
+sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
=item *
-MPE/iX
-
-MPE/iX update after Perl 5.6.0. See README.mpeix.
+C<Locale::Constants>, C<Locale::Country>, C<Locale::Currency>, and
+C<Locale::Language>, from Neil Bowers, have been added. They provide the
+codes for various locale standards, such as "fr" for France, "usd" for
+US Dollar, and "jp" for Japanese.
-=item *
+ use Locale::Country;
-NetBSD/sparc
+ $country = code2country('jp'); # $country gets 'Japan'
+ $code = country2code('Norway'); # $code gets 'no'
-Perl now works on NetBSD/sparc.
+See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
+and L<Locale::Language>.
=item *
-OS/2
-
-Now works with usethreads (see INSTALL).
+C<Locale::Maketext> is localization framework from Sean Burke. See
+L<Locale::Maketext>, and L<Locale::Maketext::TPJ13>. The latter is an
+article about software localization, originally published in The Perl
+Journal #13, republished here with kind permission.
=item *
-Solaris
-
-64-bitness using the Sun Workshop compiler now works.
+C<Memoize> can make your functions faster by trading space for time,
+from Mark-Jason Dominus. See L<Memoize>.
=item *
-Tru64 (aka Digital UNIX, aka DEC OSF/1)
+C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
+as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
+Extensions)>.
-The operating system version letter now recorded in $Config{osvers}.
-Allow compiling with gcc (previously explicitly forbidden). Compiling
-with gcc still not recommended because buggy code results, even with
-gcc 2.95.2.
+ use MIME::Base64;
-=item *
+ $encoded = encode_base64('Aladdin:open sesame');
+ $decoded = decode_base64($encoded);
-Unicos
+ print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
-Fixed various alignment problems that lead into core dumps either
-during build or later; no longer dies on math errors at runtime;
-now using full quad integers (64 bits), previously was using
-only 46 bit integers for speed.
+See L<MIME::Base64>.
=item *
-VMS
+C<MIME::QuotedPrint> allows you to encode data in quoted-printable
+encoding, as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
+Extensions)>, from Gisle Aas.
-chdir() now works better despite a CRT bug; now works with MULTIPLICITY
-(see INSTALL); now works with Perl's malloc.
+ use MIME::QuotedPrint;
-=item *
+ $encoded = encode_qp("Smiley in Unicode: \x{263a}");
+ $decoded = decode_qp($encoded);
-Windows
+ print $encoded, "\n"; # "Smiley in Unicode: =263A"
-=over 8
+MIME::QuotedPrint has been enhanced to provide the basic methods
+necessary to use it with PerlIO::Via as in :
-=item *
+ use MIME::QuotedPrint;
+ open($fh,">Via(MIME::QuotedPrint)",$path);
-accept() no longer leaks memory.
+See L<MIME::QuotedPrint>.
=item *
-Better chdir() return value for a non-existent directory.
+C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
+See L<NEXT>.
=item *
-New %ENV entries now propagate to subprocesses.
+C<open> is a new pragma for setting the default I/O disciplines
+for open().
=item *
-$ENV{LIB} now used to search for libs under Visual C.
+C<PerlIO::Scalar> provides the implementation of IO to "in memory"
+Perl scalars as discussed above, from Nick Ing-Simmons. It also
+serves as an example of a loadable PerlIO layer. Other future
+possibilities include PerlIO::Array and PerlIO::Code.
+See L<PerlIO::Scalar>.
=item *
-A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
+C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
+functionality provided by a class (typically implemented in perl
+code), from Nick Ing-Simmons.
-=item *
+ use MIME::QuotedPrint;
+ open($fh,">Via(MIME::QuotedPrint)",$path);
-Allow REG_EXPAND_SZ keys in the registry.
+This will automatically convert everything output to C<$fh>
+to Quoted-Printable. See L<PerlIO::Via>.
=item *
-Can now send() from all threads, not just the first one.
+C<Pod::ParseLink>, by Russ Allbery, has been added,
+to parse LZ<><> links in pods as described in the new
+perlpodspec.
=item *
-Fake signal handling reenabled, bugs and all.
+C<Pod::Text::Overstrike>, by Joe Smith, has been added.
+It converts POD data to formatted overstrike text.
+See L<Pod::Text::Overstrike>.
=item *
-Less stack reserved per thread so that more threads can run
-concurrently. (Still 16M per thread.)
+C<Scalar::Util> is a selection of general-utility scalar subroutines,
+like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
=item *
-C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
-(works better when perl is running as service).
+C<sort> is a new pragma for controlling the behaviour of sort().
=item *
-Better UNC path handling under ithreads.
+C<Storable> gives persistence to Perl data structures by allowing the
+storage and retrieval of Perl data to and from files in a fast and
+compact binary format, from Raphael Manfredi. See L<Storable>.
=item *
-wait() and waitpid() now work much better.
-
-=item *
+C<Switch>, from Damian Conway, has been added. Just by saying
-winsock handle leak fixed.
+ use Switch;
-=back
+you have C<switch> and C<case> available in Perl.
-=back
+ use Switch;
-=head1 New or Changed Diagnostics
+ switch ($val) {
-All regular expression compilation error messages are now hopefully
-easier to understand both because the error message now comes before
-the failed regex and because the point of failure is now clearly
-marked.
-
-The various "opened only for", "on closed", "never opened" warnings
-drop the C<main::> prefix for filehandles in the C<main> package,
-for example C<STDIN> instead of <main::STDIN>.
+ case 1 { print "number 1" }
+ case "a" { print "string a" }
+ case [1..10,42] { print "number in list" }
+ case (@array) { print "number in list" }
+ case /\w+/ { print "pattern" }
+ case qr/\w+/ { print "pattern" }
+ case (%hash) { print "entry in hash" }
+ case (\%hash) { print "entry in hash" }
+ case (\&sub) { print "arg to subroutine" }
+ else { print "previous case not true" }
+ }
-The "Unrecognized escape" warning has been extended to include C<\8>,
-C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
+See L<Switch>.
-=head1 Changed Internals
+=item *
-=over 4
+C<Test::More> is yet another framework for writing test scripts,
+more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
=item *
-perlapi.pod (a companion to perlguts) now attempts to document the
-internal API.
+C<Test::Simple> has basic utilities for writing tests, by Michael
+Schwern. See L<Test::Simple>.
=item *
-You can now build a really minimal perl called microperl.
-Building microperl does not require even running Configure;
-C<make -f Makefile.micro> should be enough. Beware: microperl makes
-many assumptions, some of which may be too bold; the resulting
-executable may crash or otherwise misbehave in wondrous ways.
-For careful hackers only.
+C<Text::Balanced> has been added, for extracting delimited text
+sequences from strings, from Damian Conway.
-=item *
+ use Text::Balanced 'extract_delimited';
-Added rsignal(), whichsig(), do_join() to the publicised API.
+ ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
-=item *
+$a will be "'never say never'", $b will be ', he never said'.
-Made possible to propagate customised exceptions via croak()ing.
+In addition to extract_delimited() there are also extract_bracketed(),
+extract_quotelike(), extract_codeblock(), extract_variable(),
+extract_tagged(), extract_multiple(), gen_delimited_pat(), and
+gen_extract_tagged(). With these you can implement rather advanced
+parsing algorithms. See L<Text::Balanced>.
=item *
-Added is_utf8_char(), is_utf8_string(), bytes_to_utf8(), and utf8_to_bytes().
+C<threads> is an interface to interpreter threads, by Arthur Bergman.
+Interpreter threads (ithreads) is the new thread model introduced in
+Perl 5.6 but only available as an internal interface for extension
+writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
=item *
-Now xsubs can have attributes just like subs.
+C<threads::shared> allows data sharing for interpreter threads, from
+Arthur Bergman. In the ithreads model any data sharing between
+threads must be explicit, as opposed to the old 5.005 thread model
+where data sharing was implicit. See L<threads::shared>.
-=back
+=item *
-=head1 Known Problems
+C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
+references (unlike the standard Tie::RefHash) The module is contained
+within Tie::RefHash, see L<Tie::RefHash>.
-=head2 Unicode Support Still Far From Perfect
+=item *
-We're working on it. Stay tuned.
+C<Time::HiRes> provides high resolution timing (ualarm, usleep,
+and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
-=head2 EBCDIC Still A Lost Platform
+=item *
-The plan is to bring them back.
+C<Unicode::UCD> offers a querying interface to the Unicode Character
+Database. See L<Unicode::UCD>.
-=head2 Building Extensions Can Fail Because Of Largefiles
+=item *
-Certain extensions like mod_perl and BSD::Resource are known to have
-issues with `largefiles', a change brought by Perl 5.6.0 in which file
-offsets default to 64 bits wide, where supported. Modules may fail to
-compile at all or compile and work incorrectly. Currently there is no
-good solution for the problem, but Configure now provides appropriate
-non-largefile ccflags, ldflags, libswanted, and libs in the %Config
-hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
-having problems can try configuring themselves without the
-largefileness. This is admittedly not a clean solution, and the
-solution may not even work at all. One potential failure is whether
-one can (or, if one can, whether it's a good idea) link together at
-all binaries with different ideas about file offsets, all this is
-platform-dependent.
+C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
+for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
-=head2 ftmp-security tests warn 'system possibly insecure'
+=item *
-Don't panic. Read INSTALL 'make test' section instead.
+C<Unicode::Normalize> implements the various Unicode normalization
+forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
-=head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX
+=item *
-If perl is configured with -Duse64bitall, the successful result of the
-subtest 10 of lib/posix may arrive before the successful result of the
-subtest 9, which confuses the test harness so much that it thinks the
-subtest 9 failed.
+C<XS::Typemap>, by Tim Jenness, is a test extension that exercises XS
+typemaps. Nothing gets installed but for extension writers the code
+is worth studying.
-=head2 Long Doubles Still Don't Work In Solaris
+=back
-The experimental long double support is still very much so in Solaris.
-(Other platforms like Linux and Tru64 are beginning to solidify in
-this area.)
+=head2 Updated And Improved Modules and Pragmata
-=head2 Linux With Sfio Fails op/misc Test 48
+=over 4
-No known fix.
+=item *
-=head2 Storable tests fail in some platforms
+The following independently supported modules have been updated to the
+newest versions from CPAN: CGI, CPAN, DB_File, File::Spec, File::Temp,
+Getopt::Long, Math::BigFloat, Math::BigInt, the podlators bundle
+(Pod::Man, Pod::Text), Pod::LaTeX, Pod::Parser, Storable,
+Term::ANSIColor, Test, Text-Tabs+Wrap.
-If any Storable tests fail the use of Storable is not advisable.
+=item *
-=over 4
+The attributes::reftype() now works on tied arguments.
=item *
-Many Storable tests fail on AIX configured with 64 bit integers.
-
-So far unidentified problems break Storable in AIX if Perl is
-configured to use 64 bit integers. AIX in 32-bit mode works and
-other 64-bit platforms work with Storable.
+AutoLoader can now be disabled with C<no AutoLoader;>.
=item *
-DOS DJGPP may hang when testing Storable.
+B::Deparse has been significantly enhanced. It now can deparse almost
+all of the standard test suite (so that the tests still succeed).
+There is a make target "test.deparse" for trying this out.
=item *
-st-06compat fails in UNICOS and UNICOS/mk.
-
-This means that you cannot read old (pre-Storable-0.7) Storable images
-made in other platforms.
+Class::Struct can now define the classes in compile time.
=item *
-st-store.t and st-retrieve may fail with Compaq C 6.2 on OpenVMS Alpha 7.2.
-
-=back
+Class::Struct now assigns the array/hash element if the accessor
+is called with an array/hash element as the B<sole> argument.
-=head2 Threads Are Still Experimental
+=item *
-Multithreading is still an experimental feature. Some platforms
-emit the following message for lib/thr5005
+Data::Dumper has now an option to sort hashes.
- #
- # This is a KNOWN FAILURE, and one of the reasons why threading
- # is still an experimental feature. It is here to stop people
- # from deploying threads in production. ;-)
- #
+=item *
-and another known thread-related warning is
+Data::Dumper has now an option to dump code references
+using B::Deparse.
- pragma/overload......Unbalanced saves: 3 more saves than restores
- panic: magic_mutexfree during global destruction.
- ok
- lib/selfloader.......Unbalanced saves: 3 more saves than restores
- panic: magic_mutexfree during global destruction.
- ok
- lib/st-dclone........Unbalanced saves: 3 more saves than restores
- panic: magic_mutexfree during global destruction.
- ok
+=item *
-=head2 The Compiler Suite Is Still Experimental
+DB_File now supports newer Berkeley DB versions, among
+other improvements.
-The compiler suite is slowly getting better but is nowhere near
-working order yet. The backend part that has seen perhaps the most
-progress is the bytecode compiler.
+=item *
-=head1 Security Vulnerability Closed
+The English module can now be used without the infamous performance
+hit by saying
-(This change was already made in 5.7.0 but bears repeating here.)
+ use English '-no_performance_hit';
-A potential security vulnerability in the optional suidperl component
-of Perl was identified in August 2000. suidperl is neither built nor
-installed by default. As of April 2001 the only known vulnerable
-platform is Linux, most likely all Linux distributions. CERT and
-various vendors and distributors have been alerted about the vulnerability.
-See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
-for more information.
+(Assuming, of course, that one doesn't need the troublesome variables
+C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
+C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
-The problem was caused by Perl trying to report a suspected security
-exploit attempt using an external program, /bin/mail. On Linux
-platforms the /bin/mail program had an undocumented feature which
-when combined with suidperl gave access to a root shell, resulting in
-a serious compromise instead of reporting the exploit attempt. If you
-don't have /bin/mail, or if you have 'safe setuid scripts', or if
-suidperl is not installed, you are safe.
+=item *
-The exploit attempt reporting feature has been completely removed from
-all the Perl 5.7 releases (and will be gone also from the maintenance
-release 5.6.1), so that particular vulnerability isn't there anymore.
-However, further security vulnerabilities are, unfortunately, always
-possible. The suidperl code is being reviewed and if deemed too risky
-to continue to be supported, it may be completely removed from future
-releases. In any case, suidperl should only be used by security
-experts who know exactly what they are doing and why they are using
-suidperl instead of some other solution such as sudo (see
-http://www.courtesan.com/sudo/).
+Fcntl, Socket, and Sys::Syslog have been rewritten to use the
+new-style constant dispatch section (see L<ExtUtils::Constant>).
+This means that they will be more robust and hopefully faster.
-=head1 Incompatible Changes
+=item *
-=over 4
+File::Find now chdir()s correctly when chasing symbolic links.
=item *
-Although "you shouldn't do that", it was possible to write code that
-depends on Perl's hashed key order (Data::Dumper does this). The new
-algorithm "One-at-a-Time" produces a different hashed key order.
-More details are in L</"Performance Enhancements">.
+File::Find now has pre- and post-processing callbacks. It also
+correctly changes directories when chasing symbolic links. Callbacks
+(naughtily) exiting with "next;" instead of "return;" now work.
=item *
-The list of filenames from glob() (or <...>) is now by default sorted
-alphabetically to be csh-compliant. (bsd_glob() does still sort platform
-natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.)
+File::Find is now (again) reentrant. It also has been made
+more portable.
-=back
+=item *
-=head1 Core Enhancements
+File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
+prototype mismatch with CORE::glob().
-=head2 AUTOLOAD Is Now Lvaluable
+=item *
-AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
-to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
+File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
+the returned list of filenames.
-=head2 PerlIO is Now The Default
+=item *
-=over 4
+Devel::Peek now has an interface for the Perl memory statistics
+(this works only if you are using perl's malloc, and if you have
+compiled with debugging).
=item *
-IO is now by default done via PerlIO rather than system's "stdio".
-PerlIO allows "layers" to be "pushed" onto a file handle to alter the
-handle's behaviour. Layers can be specified at open time via 3-arg
-form of open:
+IPC::Open3 now allows the use of numeric file descriptors.
- open($fh,'>:crlf :utf8', $path) || ...
+=item *
-or on already opened handles via extended C<binmode>:
+IO::Socket has now atmark() method, which returns true if the socket
+is positioned at the out-of-band mark. The method is also exportable
+as a sockatmark() function.
- binmode($fh,':encoding(iso-8859-7)');
+=item *
-The built-in layers are: unix (low level read/write), stdio (as in
-previous Perls), perlio (re-implementation of stdio buffering in a
-portable manner), crlf (does CRLF <=> "\n" translation as on Win32,
-but available on any platform). A mmap layer may be available if
-platform supports it (mostly UNIXes).
+IO::Socket::INET has support for ReusePort option (if your platform
+supports it). The Reuse option now has an alias, ReuseAddr. For clarity
+you may want to prefer ReuseAddr.
-Layers to be applied by default may be specified via the 'open' pragma.
+=item *
-See L</"Installation and Configuration Improvements"> for the effects
-of PerlIO on your architecture name.
+IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
+that the operating system will make one up.)
=item *
-File handles can be marked as accepting Perl's internal encoding of Unicode
-(UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer ":utf8" :
+use lib now works identically to @INC. Removing directories
+with 'no lib' now works.
- open($fh,">:utf8","Uni.txt");
+=item *
-Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
-for you since it's not UTF-8 what you will be getting but instead
-UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
-http://www.unicode.org/unicode/reports/tr16/ for more information.
-In future releases this naming may change.
+Math::BigFloat and Math::BigInt have undergone a full rewrite.
+They are now magnitudes faster, and they support various
+bignum libraries such as GMP and PARI as their backends.
=item *
-File handles can translate character encodings from/to Perl's internal
-Unicode form on read/write via the ":encoding()" layer.
+Math::Complex handles inf, NaN etc., better.
=item *
-File handles can be opened to "in memory" files held in Perl scalars via:
-
- open($fh,'>', \$variable) || ...
+Net::Ping has been enhanced. There is now "external" protocol which
+uses Net::Ping::External module which runs external ping(1) and parses
+the output. A version of Net::Ping::External is available in CPAN.
=item *
-Anonymous temporary files are available without need to
-'use FileHandle' or other module via
+POSIX::sigaction() is now much more flexible and robust.
+You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
+handlers, installing new handlers was not atomic.
- open($fh,"+>", undef) || ...
+=item *
-That is a literal undef, not an undefined value.
+In Safe the C<%INC> now localised in a Safe compartment so that
+use/require work.
=item *
-The list form of C<open> is now implemented for pipes (at least on UNIX):
+In SDBM_File on dosish platforms, some keys went missing because of
+lack of support for files with "holes". A workaround for the problem
+has been added.
- open($fh,"-|", 'cat', '/etc/motd')
+=item *
-creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
-the child process.
+In Search::Dict one can now have a pre-processing hook for the
+lines being searched.
=item *
-The following builtin functions are now overridable: chop(), chomp(),
-each(), keys(), pop(), push(), shift(), splice(), unshift().
+The Shell module now has an OO interface.
=item *
-Formats now support zero-padded decimal fields.
+The Test module has been significantly enhanced.
=item *
-Perl now tries internally to use integer values in numeric conversions
-and basic arithmetics (+ - * /) if the arguments are integers, and
-tries also to keep the results stored internally as integers.
-This change leads into often slightly faster and always less lossy
-arithmetics. (Previously Perl always preferred floating point numbers
-in its math.)
+The vars pragma now supports declaring fully qualified variables.
+(Something that C<our()> does not and will not support.)
=item *
-The printf() and sprintf() now support parameter reordering using the
-C<%\d+\$> and C<*\d+\$> syntaxes. For example
+The utf8:: name space (as in the pragma) provides various
+Perl-callable functions to provide low level access to Perl's
+internal Unicode representation. At the moment only length()
+has been implemented.
- print "%2\$s %1\$s\n", "foo", "bar";
+=back
-will print "bar foo\n"; This feature helps in writing
-internationalised software.
+=head1 Utility Changes
+
+=over 4
=item *
-Unicode in general should be now much more usable. Unicode can be
-used in hash keys, Unicode in regular expressions should work now,
-Unicode in tr/// should work now (though tr/// seems to be a
-particularly tricky to get right, so you have been warned)
+Emacs perl mode (emacs/cperl-mode.el) has been updated to version
+4.31.
=item *
-The Unicode Character Database coming with Perl has been upgraded
-to Unicode 3.1. For more information, see http://www.unicode.org/,
-and http://www.unicode.org/unicode/reports/tr27/
-
-For developers interested in enhancing Perl's Unicode capabilities:
-almost all the UCD files are included with the Perl distribution in
-the lib/unicode subdirectory. The most notable omission, for space
-considerations, is the Unihan database.
+F<emacs/e2ctags.pl> is now much faster.
=item *
-The Unicode character classes \p{Blank} and \p{SpacePerl} have been
-added. "Blank" is like C isblank(), that is, it contains only
-"horizontal whitespace" (the space character is, the newline isn't),
-and the "SpacePerl" is the Unicode equivalent of C<\s> (\p{Space}
-isn't, since that includes the vertical tabulator character, whereas
-C<\s> doesn't.)
+C<h2ph> now supports C trigraphs.
-=back
+=item *
-=head2 Signals Are Now Safe
+C<h2xs> now produces a template README.
-Perl used to be fragile in that signals arriving at inopportune moments
-could corrupt Perl's internal state.
+=item *
-=head1 Modules and Pragmata
+C<h2xs> now uses C<Devel::PPort> for better portability between
+different versions of Perl.
-=head2 New Modules
+=item *
-=over 4
+C<h2xs> uses the new L<ExtUtils::Constant> module which will affect
+newly created extensions that define constants. Since the new code is
+more correct (if you have two constants where the first one is a
+prefix of the second one, the first constant B<never> gets defined),
+less lossy (it uses integers for integer constant, as opposed to the
+old code that used floating point numbers even for integer constants),
+and slightly faster, you might want to consider regenerating your
+extension code (the new scheme makes regenerating easy).
+L<h2xs> now also supports C trigraphs.
=item *
-B::Concise, by Stephen McCamant, is a new compiler backend for
-walking the Perl syntax tree, printing concise info about ops.
-The output is highly customisable.
+C<libnetcfg> has been added to configure the libnet.
+
+=item *
-See L<B::Concise> for more information.
+C<perlbug> is now much more robust. It also sends the bug report to
+perl.org, not perl.com.
=item *
-Class::ISA, by Sean Burke, for reporting the search path for a
-class's ISA tree, has been added.
+C<perlcc> has been rewritten and its user interface (that is,
+command line) is much more like that of the UNIX C compiler, cc.
+(The perlbc tools has been removed. Use C<perlcc -B> instead.)
+
+=item *
-See L<Class::ISA> for more information.
+C<perlivp> is a new Installation Verification Procedure utility
+for running any time after installing Perl.
=item *
-Cwd has now a split personality: if possible, an extension is used,
-(this will hopefully be both faster and more secure and robust) but
-if not possible, the familiar Perl library implementation is used.
+C<pod2html> now allows specifying a cache directory.
=item *
-Digest, a frontend module for calculating digests (checksums),
-from Gisle Aas, has been added.
+C<s2p> has been completely rewritten in Perl. (It is in fact a full
+implementation of sed in Perl: you can use the sed functionality by
+using the C<psed> utility.)
-See L<Digest> for more information.
+=item *
+
+C<xsubpp> now understands POD documentation embedded in the *.xs files.
=item *
-Digest::MD5 for calculating MD5 digests (checksums), by Gisle Aas,
-has been added.
+C<xsubpp> now supports OUT keyword.
- use Digest::MD5 'md5_hex';
+=back
- $digest = md5_hex("Thirsty Camel");
+=head1 New Documentation
- print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
+=over 4
-NOTE: the MD5 backward compatibility module is deliberately not
-included since its use is discouraged.
+=item *
-See L<Digest::MD5> for more information.
+perl56delta details the changes between the 5.005 release and the
+5.6.0 release.
=item *
-Encode, by Nick Ing-Simmons, provides a mechanism to translate
-between different character encodings. Support for Unicode,
-ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
-compiled in to the module. Several other encodings (like Japanese,
-Chinese, and MacIntosh encodings) are included and will be loaded at
-runtime.
-
-Any encoding supported by Encode module is also available to the
-":encoding()" layer if PerlIO is used.
-
-See L<Encode> for more information.
+perlclib documents the internal replacements for standard C library
+functions. (Interesting only for extension writers and Perl core
+hackers.)
=item *
-Filter::Simple is an easy-to-use frontend to Filter::Util::Call,
-from Damian Conway.
-
- # in MyFilter.pm:
-
- package MyFilter;
-
- use Filter::Simple sub {
- while (my ($from, $to) = splice @_, 0, 2) {
- s/$from/$to/g;
- }
- };
-
- 1;
-
- # in user's code:
-
- use MyFilter qr/red/ => 'green';
-
- print "red\n"; # this code is filtered, will print "green\n"
- print "bored\n"; # this code is filtered, will print "bogreen\n"
-
- no MyFilter;
-
- print "red\n"; # this code is not filtered, will print "red\n"
-
-See L<Filter::Simple> for more information.
+perldebtut is a Perl debugging tutorial.
=item *
-Filter::Util::Call, by Paul Marquess, provides you with the
-framework to write I<Source Filters> in Perl. For most uses
-the frontend Filter::Simple is to be preferred.
-See L<Filter::Util::Call> for more information.
+perlebcdic contains considerations for running Perl on EBCDIC platforms.
=item *
-Locale::Constants, Locale::Country, Locale::Currency, and Locale::Language,
-from Neil Bowers, have been added. They provide the codes for various
-locale standards, such as "fr" for France, "usd" for US Dollar, and
-"jp" for Japanese.
-
- use Locale::Country;
-
- $country = code2country('jp'); # $country gets 'Japan'
- $code = country2code('Norway'); # $code gets 'no'
-
-See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
-and L<Locale::Language> for more information.
+perlintro is a gentle introduction to Perl.
=item *
-MIME::Base64, by Gisle Aas, allows you to encode data in base64.
+perliol documents the internals of PerlIO with layers.
- use MIME::Base64;
+=item *
- $encoded = encode_base64('Aladdin:open sesame');
- $decoded = decode_base64($encoded);
+perlmodstyle is a style guide for writing modules.
- print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
+=item *
-See L<MIME::Base64> for more information.
+perlnewmod tells about writing and submitting a new module.
=item *
-MIME::QuotedPrint, by Gisle Aas, allows you to encode data in
-quoted-printable encoding.
+perlpacktut is a pack() tutorial.
- use MIME::QuotedPrint;
+=item *
- $encoded = encode_qp("Smiley in Unicode: \x{263a}");
- $decoded = decode_qp($encoded);
+perlpod has been rewritten to be clearer and to record the best
+practices gathered over the years.
- print $encoded, "\n"; # "Smiley in Unicode: =263A"
+=item *
-MIME::QuotedPrint has been enhanced to provide the basic methods
-necessary to use it with PerlIO::Via as in :
+perlpodspec is a more formal specification of the pod format,
+mainly of interest for writers of pod applications, not to
+people writing in pod.
- use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+=item *
-See L<MIME::QuotedPrint> for more information.
+perlretut is a regular expression tutorial.
=item *
-PerlIO::Scalar, by Nick Ing-Simmons, provides the implementation of
-IO to "in memory" Perl scalars as discussed above. It also serves as
-an example of a loadable layer. Other future possibilities include
-PerlIO::Array and PerlIO::Code. See L<PerlIO::Scalar> for more
-information.
+perlrequick is a regular expressions quick-start guide.
+Yes, much quicker than perlretut.
=item *
-PerlIO::Via, by Nick Ing-Simmons, acts as a PerlIO layer and wraps
-PerlIO layer functionality provided by a class (typically implemented
-in perl code).
+perltodo has been updated.
- use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+=item *
-This will automatically convert everything output to C<$fh>
-to Quoted-Printable. See L<PerlIO::Via> for more information.
+perltootc has been renamed as perltooc (to not to conflict
+with perltoot in filesystems restricted to "8.3" names)
=item *
-Pod::Text::Overstrike, by Joe Smith, has been added.
-It converts POD data to formatted overstrike text.
-See L<Pod::Text::Overstrike> for more information.
+perluniintro is an introduction to using Unicode in Perl
+(perlunicode is more of a reference)
=item *
-Switch from Damian Conway has been added. Just by saying
+perlutil explains the command line utilities packaged with the Perl
+distribution.
- use Switch;
+=back
-you have C<switch> and C<case> available in Perl.
+The following platform-specific documents are available before
+the installation as README.I<platform>, and after the installation
+as perlI<platform>:
- use Switch;
+ perlaix perlamiga perlapollo perlbeos perlbs2000
+ perlce perlcygwin perldgux perldos perlepoc perlhpux
+ perlhurd perlmachten perlmacos perlmint perlmpeix
+ perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
+ perltru64 perluts perlvmesa perlvms perlvos perlwin32
- switch ($val) {
+=over 4
- case 1 { print "number 1" }
- case "a" { print "string a" }
- case [1..10,42] { print "number in list" }
- case (@array) { print "number in list" }
- case /\w+/ { print "pattern" }
- case qr/\w+/ { print "pattern" }
- case (%hash) { print "entry in hash" }
- case (\%hash) { print "entry in hash" }
- case (\&sub) { print "arg to subroutine" }
- else { print "previous case not true" }
- }
+=item *
-See L<Switch> for more information.
+The documentation for the POSIX-BC platform is called "BS2000", to avoid
+confusion with the Perl POSIX module.
=item *
-Text::Balanced from Damian Conway has been added, for
-extracting delimited text sequences from strings.
+The documentation for the WinCE platform is called "CE", to avoid
+confusion with the perlwin32 documentation on 8.3-restricted filesystems.
- use Text::Balanced 'extract_delimited';
+=back
- ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
+=head1 Performance Enhancements
-$a will be "'never say never'", $b will be ', he never said'.
+=over 4
-In addition to extract_delimited() there are also extract_bracketed(),
-extract_quotelike(), extract_codeblock(), extract_variable(),
-extract_tagged(), extract_multiple(), gen_delimited_pat(), and
-gen_extract_tagged(). With these you can implement rather advanced
-parsing algorithms. See L<Text::Balanced> for more information.
+=item *
+
+map() could get pathologically slow when the result list it generates
+is larger than the source list. The performance has been improved for
+common scenarios.
+
+=item *
+
+sort() has been changed to use primarily mergesort internally as
+opposed to the earlier quicksort. For very small lists this may
+result in slightly slower sorting times, but in general the speedup
+should be at least 20%. Additional bonuses are that the worst case
+behaviour of sort() is now better (in computer science terms it now
+runs in time O(N log N), as opposed to quicksort's Theta(N**2)
+worst-case run time behaviour), and that sort() is now stable
+(meaning that elements with identical keys will stay ordered as they
+were before the sort). See the C<sort> pragma for information.
+
+The story in more detail: suppose you want to serve yourself a little
+slice of Pi.
+
+ @digits = ( 3,1,4,1,5,9 );
+
+A numerical sort of the digits will yield (1,1,3,4,5,9), as expected.
+Which C<1> comes first is hard to know, since one C<1> looks pretty
+much like any other. You can regard this as totally trivial,
+or somewhat profound. However, if you just want to sort the even
+digits ahead of the odd ones, then what will
+
+ sort { ($a % 2) <=> ($b % 2) } @digits;
+
+yield? The only even digit, C<4>, will come first. But how about
+the odd numbers, which all compare equal? With the quicksort algorithm
+used to implement Perl 5.6 and earlier, the order of ties is left up
+to the sort. So, as you add more and more digits of Pi, the order
+in which the sorted even and odd digits appear will change.
+and, for sufficiently large slices of Pi, the quicksort algorithm
+in Perl 5.8 won't return the same results even if reinvoked with the
+same input. The justification for this rests with quicksort's
+worst case behavior. If you run
+
+ sort { $a <=> $b } ( 1 .. $N , 1 .. $N );
+
+(something you might approximate if you wanted to merge two sorted
+arrays using sort), doubling $N doesn't just double the quicksort time,
+it I<quadruples> it. Quicksort has a worst case run time that can
+grow like N**2, so-called I<quadratic> behaviour, and it can happen
+on patterns that may well arise in normal use. You won't notice this
+for small arrays, but you I<will> notice it with larger arrays,
+and you may not live long enough for the sort to complete on arrays
+of a million elements. So the 5.8 quicksort scrambles large arrays
+before sorting them, as a statistical defence against quadratic behaviour.
+But that means if you sort the same large array twice, ties may be
+broken in different ways.
+
+Because of the unpredictability of tie-breaking order, and the quadratic
+worst-case behaviour, quicksort was I<almost> replaced completely with
+a stable mergesort. I<Stable> means that ties are broken to preserve
+the original order of appearance in the input array. So
+
+ sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
+
+will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers
+appear in the output in the same order they appeared in the input.
+Mergesort has worst case O(NlogN) behaviour, the best value
+attainable. And, ironically, this mergesort does particularly
+well where quicksort goes quadratic: mergesort sorts (1..$N, 1..$N)
+in O(N) time. But quicksort was rescued at the last moment because
+it is faster than mergesort on certain inputs and platforms.
+For example, if you really I<don't> care about the order of even
+and odd digits, quicksort will run in O(N) time; it's very good
+at sorting many repetitions of a small number of distinct elements.
+The quicksort divide and conquer strategy works well on platforms
+with relatively small, very fast, caches. Eventually, the problem gets
+whittled down to one that fits in the cache, from which point it
+benefits from the increased memory speed.
+
+Quicksort was rescued by implementing a sort pragma to control aspects
+of the sort. The B<stable> subpragma forces stable behaviour,
+regardless of algorithm. The B<_quicksort> and B<_mergesort>
+subpragmas are heavy-handed ways to select the underlying implementation.
+The leading C<_> is a reminder that these subpragmas may not survive
+beyond 5.8. More appropriate mechanisms for selecting the implementation
+exist, but they wouldn't have arrived in time to save quicksort.
=item *
-Tie::RefHash::Nestable, by Edward Avis, allows storing hash references
-(unlike the standard Tie::RefHash) The module is contained within
-Tie::RefHash.
+Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
+(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
+reasonably fast while producing a much better spread of values than
+the old hashing algorithm (originally by Chris Torek, later tweaked by
+Ilya Zakharevich). Hash values output from the algorithm on a hash of
+all 3-char printable ASCII keys comes much closer to passing the
+DIEHARD random number generation tests. According to perlbench, this
+change has not affected the overall speed of Perl.
=item *
-XS::Typemap, by Tim Jenness, is a test extension that exercises XS
-typemaps. Nothing gets installed but for extension writers the code
-is worth studying.
+unshift() should now be noticeably faster.
=back
-=head2 Updated And Improved Modules and Pragmata
+=head1 Installation and Configuration Improvements
+
+=head2 Generic Improvements
=over 4
=item *
-B::Deparse should be now more robust. It still far from providing a full
-round trip for any random piece of Perl code, though, and is under active
-development: expect more robustness in 5.7.2.
+INSTALL now explains how you can configure Perl to use 64-bit
+integers even on non-64-bit platforms.
=item *
-Class::Struct can now define the classes in compile time.
+Policy.sh policy change: if you are reusing a Policy.sh file
+(see INSTALL) and you use Configure -Dprefix=/foo/bar and in the old
+Policy $prefix eq $siteprefix and $prefix eq $vendorprefix, all of
+them will now be changed to the new prefix, /foo/bar. (Previously
+only $prefix changed.) If you do not like this new behaviour,
+specify prefix, siteprefix, and vendorprefix explicitly.
=item *
-Math::BigFloat has undergone much fixing, and in addition the fmod()
-function now supports modulus operations.
-
-(The fixed Math::BigFloat module is also available in CPAN for those
-who can't upgrade their Perl: http://www.cpan.org/authors/id/J/JP/JPEACOCK/)
+A new optional location for Perl libraries, otherlibdirs, is available.
+It can be used for example for vendor add-ons without disturbing Perl's
+own library directories.
=item *
-Devel::Peek now has an interface for the Perl memory statistics
-(this works only if you are using perl's malloc, and if you have
-compiled with debugging).
+In many platforms the vendor-supplied 'cc' is too stripped-down to
+build Perl (basically, 'cc' doesn't do ANSI C). If this seems
+to be the case and 'cc' does not seem to be the GNU C compiler
+'gcc', an automatic attempt is made to find and use 'gcc' instead.
=item *
-IO::Socket has now atmark() method, which returns true if the socket
-is positioned at the out-of-band mark. The method is also exportable
-as a sockatmark() function.
+gcc needs to closely track the operating system release to avoid
+build problems. If Configure finds that gcc was built for a different
+operating system release than is running, it now gives a clearly visible
+warning that there may be trouble ahead.
=item *
-IO::Socket::INET has support for ReusePort option (if your platform
-supports it). The Reuse option now has an alias, ReuseAddr. For clarity
-you may want to prefer ReuseAddr.
+If binary compatibility with the 5.005 release is not wanted, Configure
+no longer suggests including the 5.005 modules in @INC.
=item *
-Net::Ping has been enhanced. There is now "external" protocol which
-uses Net::Ping::External module which runs external ping(1) and parses
-the output. An alpha version of Net::Ping::External is available in
-CPAN and in 5.7.2 the Net::Ping::External may be integrated to Perl.
+Configure C<-S> can now run non-interactively.
=item *
-The C<open> pragma allows layers other than ":raw" and ":crlf" when
-using PerlIO.
+Configure support for pdp11-style memory models has been removed due
+to obsolescence.
=item *
-POSIX::sigaction() is now much more flexible and robust.
-You can now install coderef handlers, 'DEFAULT', and 'IGNORE'
-handlers, installing new handlers was not atomic.
+configure.gnu now works with options with whitespace in them.
=item *
-The Test module has been significantly enhanced. Its use is
-greatly recommended for module writers.
+installperl now outputs everything to STDERR.
=item *
-The utf8:: name space (as in the pragma) provides various
-Perl-callable functions to provide low level access to Perl's
-internal Unicode representation. At the moment only length()
-has been implemented.
+$Config{byteorder} is now computed dynamically (this is more robust
+with "fat binaries" where an executable image contains binaries for
+more than one binary platform.)
-=back
+=item *
-The following modules have been upgraded from the versions at CPAN:
-CPAN, CGI, DB_File, File::Temp, Getopt::Long, Pod::Man, Pod::Text,
-Storable, Text-Tabs+Wrap.
+Because PerlIO is now the default on most platforms, "-perlio" doesn't
+get appended to the $Config{archname} (also known as $^O) anymore.
+Instead, if you explicitly choose not to use perlio (Configure command
+line option -Uuseperlio), you will get "-stdio" appended.
-=head1 Performance Enhancements
+=item *
-=over 4
+Another change related to the architecture name is that "-64all"
+(-Duse64bitall, or "maximally 64-bit") is appended only if your
+pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
=item *
-Hashes now use Bob Jenkins "One-at-a-Time" hashing key algorithm
-(http://burtleburtle.net/bob/hash/doobs.html). This algorithm is
-reasonably fast while producing a much better spread of values than
-the old hashing algorithm (originally by Chris Torek, later tweaked by
-Ilya Zakharevich). Hash values output from the algorithm on a hash of
-all 3-char printable ASCII keys comes much closer to passing the
-DIEHARD random number generation tests. According to perlbench, this
-change has not affected the overall speed of Perl.
+In AFS installations one can configure the root of the AFS to be
+somewhere else than the default F</afs> by using the Configure
+parameter C<-Dafsroot=/some/where/else>.
=item *
-unshift() should now be noticeably faster.
+APPLLIB_EXP, a less-know configuration-time definition, has been
+documented. It can be used to prepend site-specific directories
+to Perl's default search path (@INC), see INSTALL for information.
-=back
+=item *
-=head1 Utility Changes
+The version of Berkeley DB used when the Perl (and, presumably, the
+DB_File extension) was built is now available as
+C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
+from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
+DB_VERSION_PATCH_CFG> from C.
-=over 4
+=item *
+
+Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
+has been documented in INSTALL.
=item *
-h2xs now produces template README.
+If you have CPAN access (either network or a local copy such as a
+CD-ROM) you can during specify extra modules to Configure to build and
+install with Perl using the -Dextras=... option. See INSTALL for
+more details.
=item *
-s2p has been completely rewritten in Perl. (It is in fact a full
-implementation of sed in Perl.)
+In addition to config.over a new override file, config.arch, is
+available. That is supposed to be used by hints file writers for
+architecture-wide changes (as opposed to config.over which is for
+site-wide changes).
=item *
-xsubpp now supports OUT keyword.
+If your file system supports symbolic links you can build Perl outside
+of the source directory by
-=back
+ mkdir /tmp/perl/build/directory
+ cd /tmp/perl/build/directory
+ sh /path/to/perl/source/Configure -Dmksymlinks ...
-=head1 New Documentation
+This will create in /tmp/perl/build/directory a tree of symbolic links
+pointing to files in /path/to/perl/source. The original files are left
+unaffected. After Configure has finished you can just say
-=head2 perlclib
+ make all test
-Internal replacements for standard C library functions.
-(Interesting only for extension writers and Perl core hackers.)
+and Perl will be built and tested, all in /tmp/perl/build/directory.
-=head2 perliol
+=item *
-Internals of PerlIO with layers.
+For Perl developers several new make targets for profiling
+and debugging have been added, see L<perlhack>.
-=head2 README.aix
+=over 8
-Documentation on compiling Perl on AIX has been added. AIX has
-several different C compilers and getting the right patch level
-is essential. On install README.aix will be installed as L<perlaix>.
+=item *
-=head2 README.bs2000
+Use of the F<gprof> tool to profile Perl has been documented in
+L<perlhack>. There is a make target called "perl.gprof" for
+generating a gprofiled Perl executable.
-Documentation on compiling Perl on the POSIX-BC platform (an EBCDIC
-mainframe environment) has been added.
+=item *
-This was formerly known as README.posix-bc but the name was considered
-to be too confusing (it has nothing to do with the POSIX module or the
-POSIX standard). On install README.bs2000 will be installed as L<perlbs2000>.
+If you have GCC 3, there is a make target called "perl.gcov" for
+creating a gcoved Perl executable for coverage analysis. See
+L<perlhack>.
-=head2 README.macos
+=item *
-In perl 5.7.1 (and in the 5.6.1) the MacPerl sources have been
-synchronised with the standard Perl sources. To compile MacPerl
-some additional steps are required, and this file documents those
-steps. On install README.macos will be installed as L<perlmacos>.
+If you are on IRIX or Tru64 platforms, new profiling/debugging options
+have been added, see L<perlhack> for more information about pixie and
+Third Degree.
-=head2 README.mpeix
+=back
-The README.mpeix has been podified, which means that this information
-about compiling and using Perl on the MPE/iX miniframe platform will
-be installed as L<perlmpeix>.
+=item *
-=head2 README.solaris
+Guidelines of how to construct minimal Perl installations have
+been added to INSTALL.
-README.solaris has been created and Solaris wisdom from elsewhere
-in the Perl documentation has been collected there. On install
-README.solaris will be installed as L<perlsolaris>.
+=item *
-=head2 README.vos
+The Thread extension is now not built at all under ithreads
+(C<Configure -Duseithreads>) because it wouldn't work anyway (the
+Thread extension requires being Configured with C<-Duse5005threads>).
-The README.vos has been podified, which means that this information
-about compiling and using Perl on the Stratus VOS miniframe platform
-will be installed as L<perlvos>.
+But note that the Thread.pm interface is now shared by both
+thread models.
-=head2 Porting/repository.pod
+=back
-Documentation on how to use the Perl source repository has been added.
+=head2 New Or Improved Platforms
-=head1 Installation and Configuration Improvements
+For the list of platforms known to support Perl,
+see L<perlport/"Supported Platforms">.
=over 4
=item *
-Because PerlIO is now the default on most platforms, "-perlio" doesn't
-get appended to the $Config{archname} (also known as $^O) anymore.
-Instead, if you explicitly choose not to use perlio (Configure command
-line option -Uuseperlio), you will get "-stdio" appended.
+AIX dynamic loading should be now better supported.
=item *
-Another change related to the architecture name is that "-64all"
-(-Duse64bitall, or "maximally 64-bit") is appended only if your
-pointers are 64 bits wide. (To be exact, the use64bitall is ignored.)
+AIX should now work better with gcc, threads, and 64-bitness. Also the
+long doubles support in AIX should be better now. See L<perlaix>.
=item *
-APPLLIB_EXP, a less-know configuration-time definition, has been
-documented. It can be used to prepend site-specific directories
-to Perl's default search path (@INC), see INSTALL for information.
+After a long pause, AmigaOS has been verified to be happy with Perl.
=item *
-Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
-has been documented in INSTALL.
+AtheOS (http://www.atheos.cx/) is a new platform.
=item *
-If you are on IRIX or Tru64 platforms, new profiling/debugging options
-have been added, see L<perlhack> for more information about pixie and
-Third Degree.
+DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
-=back
+=item *
-=head2 New Or Improved Platforms
-
-For the list of platforms known to support Perl,
-see L<perlport/"Supported Platforms">.
-
-=over 4
-
-=item *
-
-AIX dynamic loading should be now better supported.
-
-=item *
-
-After a long pause, AmigaOS has been verified to be happy with Perl.
+DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
=item *
=item *
-NCR MP-RAS is now supported.
+MacOS X (or Darwin) should now be able to build Perl even on HFS+
+filesystems. (The case-insensitivity confused the Perl build process.)
=item *
-NonStop-UX is now supported.
+NCR MP-RAS is now supported.
=item *
-Amdahl UTS is now supported.
+NetWare from Novell is now supported. See L<perlnetware>.
=item *
-z/OS (formerly known as OS/390, formerly known as MVS OE) has now
-support for dynamic loading. This is not selected by default,
-however, you must specify -Dusedl in the arguments of Configure.
-
-=back
+NonStop-UX is now supported.
-=head2 Generic Improvements
+=item *
-=over 4
+NEC SUPER-UX is now supported.
=item *
-Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
-when building the Perl binary. The only exception to this is SunOS 4.x,
-which needs them.
+Amdahl UTS UNIX mainframe platform is now supported.
=item *
-Some new Configure symbols, useful for extension writers:
+WinCE is now supported. See L<perlce>.
-=over 8
+=item *
-=item d_cmsghdr
+z/OS (formerly known as OS/390, formerly known as MVS OE) has now
+support for dynamic loading. This is not selected by default,
+however, you must specify -Dusedl in the arguments of Configure.
-For struct cmsghdr.
+=back
-=item d_fcntl_can_lock
+=head1 Selected Bug Fixes
-Whether fcntl() can be used for file locking.
+Numerous memory leaks and uninitialized memory accesses have been
+hunted down. Most importantly anonymous subs used to leak quite
+a bit.
-=item d_fsync
+=over 4
-=item d_getitimer
+=item *
-=item d_getpagsz
+The autouse pragma didn't work for Multi::Part::Function::Names.
-For getpagesize(), though you should prefer POSIX::sysconf(_SC_PAGE_SIZE))
+=item *
-=item d_msghdr_s
+caller() could cause core dumps in certain situations. Carp was sometimes
+affected by this problem.
-For struct msghdr.
+=item *
-=item need_va_copy
+chop(@list) in list context returned the characters chopped in
+reverse order. This has been reversed to be in the right order.
-Whether one needs to use Perl_va_copy() to copy varargs.
+=item *
-=item d_readv
+Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
+when building the Perl binary. The only exception to this is SunOS 4.x,
+which needs them.
-=item d_recvmsg
+=item *
-=item d_sendmsg
+The behaviour of non-decimal but numeric string constants such as
+"0x23" was platform-dependent: in some platforms that was seen as 35,
+in some as 0, in some as a floating point number (don't ask). This
+was caused by Perl using the operating system libraries in a situation
+where the result of the string to number conversion is undefined: now
+Perl consistently handles such strings as zero in numeric contexts.
-=item sig_size
+=item *
-The number of elements in an array needed to hold all the available signals.
+The order of DESTROYs has been made more predictable.
-=item d_sockatmark
+=item *
-=item d_strtoq
+Several debugger fixes: exit code now reflects the script exit code,
+condition C<"0"> now treated correctly, the C<d> command now checks
+line number, the C<$.> no longer gets corrupted, all debugger output
+now goes correctly to the socket if RemotePort is set.
-=item d_u32align
+=item *
-Whether one needs to access character data aligned by U32 sized pointers.
+Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
+when statically building extensions into perl. This has been corrected.
-=item d_ualarm
+=item *
-=item d_usleep
+L<dprofpp> -R didn't work.
-=back
+=item *
+C<*foo{FORMAT}> now works.
=item *
-Removed Configure symbols: the PDP-11 memory model settings: huge,
-large, medium, models.
+Infinity is now recognized as a number.
=item *
-SOCKS support is now much more robust.
+UNIVERSAL::isa no longer caches methods incorrectly. (This broke
+the Tk extension with 5.6.0.)
=item *
-If your file system supports symbolic links you can build Perl outside
-of the source directory by
+Lexicals I: lexicals outside an eval "" weren't resolved
+correctly inside a subroutine definition inside the eval "" if they
+were not already referenced in the top level of the eval""ed code.
- mkdir /tmp/perl/build/directory
- cd /tmp/perl/build/directory
- sh /path/to/perl/source/Configure -Dmksymlinks ...
+=item *
-This will create in /tmp/perl/build/directory a tree of symbolic links
-pointing to files in /path/to/perl/source. The original files are left
-unaffected. After Configure has finished you can just say
+Lexicals II: lexicals leaked at file scope into subroutines that
+were declared before the lexicals.
- make all test
+=item *
-and Perl will be built and tested, all in /tmp/perl/build/directory.
+Lexical warnings now propagating correctly between scopes
+and into C<eval "...">.
-=back
+=item *
-=head1 Selected Bug Fixes
+C<use warnings qw(FATAL all)> did not work as intended. This has been
+corrected.
-Numerous memory leaks and uninitialized memory accesses have been hunted down.
-Most importantly anonymous subs used to leak quite a bit.
+=item *
-=over 4
+warnings::enabled() now reports the state of $^W correctly if the caller
+isn't using lexical warnings.
=item *
-chop(@list) in list context returned the characters chopped in
-reverse order. This has been reversed to be in the right order.
+Line renumbering with eval and C<#line> now works.
=item *
-The order of DESTROYs has been made more predictable.
+Fixed numerous memory leaks, especially in eval "".
=item *
=item *
-Attributes (like :shared) didn't work with our().
+Some versions of glibc have a broken modfl(). This affects builds
+with C<-Duselongdouble>. This version of Perl detects this brokenness
+and has a workaround for it. The glibc release 2.2.2 is known to have
+fixed the modfl() bug.
=item *
-The PERL5OPT environment variable (for passing command line arguments
-to Perl) didn't work for more than a single group of options.
+Modulus of unsigned numbers now works (4063328477 % 65535 used to
+return 27406, instead of 27047).
=item *
-The tainting behaviour of sprintf() has been rationalized. It does
-not taint the result of floating point formats anymore, making the
-behaviour consistent with that of string interpolation.
+Some "not a number" warnings introduced in 5.6.0 eliminated to be
+more compatible with 5.005. Infinity is now recognised as a number.
=item *
-All but the first argument of the IO syswrite() method are now optional.
+Numeric conversions did not recognize changes in the string value
+properly in certain circumstances.
=item *
-Tie::ARRAY SPLICE method was broken.
+Attributes (like :shared) didn't work with our().
=item *
-vec() now tries to work with characters <= 255 when possible, but it leaves
-higher character values in place. In that case, if vec() was used to modify
-the string, it is no longer considered to be utf8-encoded.
-
-=back
-
-=head2 Platform Specific Changes and Fixes
-
-=over 4
+our() variables will not cause "will not stay shared" warnings.
=item *
-Linux previously had problems related to sockaddrlen when using
-accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
+"our" variables of the same name declared in two sibling blocks
+resulted in bogus warnings about "redeclaration" of the variables.
+The problem has been corrected.
=item *
-Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
+pack "Z" now correctly terminates the string with "\0".
=item *
-Windows
-
-=over 8
+Fix password routines which in some shadow password platforms
+(e.g. HP-UX) caused getpwent() to return every other entry.
=item *
-Borland C++ v5.5 is now a supported compiler that can build Perl.
-However, the generated binaries continue to be incompatible with those
-generated by the other supported compilers (GCC and Visual C++).
+The PERL5OPT environment variable (for passing command line arguments
+to Perl) didn't work for more than a single group of options.
=item *
-Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
-Other bugs in chdir() and Cwd::cwd() have also been fixed.
+PERL5OPT with embedded spaces didn't work.
=item *
-Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
+printf() no longer resets the numeric locale to "C".
=item *
-HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
+C<qw(a\\b)> now parses correctly as C<'a\\b'>.
=item *
-The makefiles now provide a single switch to bulk-enable all the features
-enabled in ActiveState ActivePerl (a popular binary distribution).
-
-=back
-
-=back
-
-=head1 New or Changed Diagnostics
-
-Two new debugging options have been added: if you have compiled your
-Perl with debugging, you can use the -DT and -DR options to trace
-tokenising and to add reference counts to displaying variables,
-respectively.
-
-=over 4
+pos() did not return the correct value within s///ge in earlier
+versions. This is now handled correctly.
=item *
-If an attempt to use a (non-blessed) reference as an array index
-is made, a warning is given.
+Printing quads (64-bit integers) with printf/sprintf now works
+without the q L ll prefixes (assuming you are on a quad-capable platform).
=item *
-C<push @a;> and C<unshift @a;> (with no values to push or unshift)
-now give a warning. This may be a problem for generated and evaled
-code.
-
-=back
-
-=head1 Changed Internals
-
-=over 4
+Regular expressions on references and overloaded scalars now work.
=item *
-Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv().
-For the full list of the available APIs see L<perlapi>.
+Right-hand side magic (GMAGIC) could in many cases such as string
+concatenation be invoked too many times.
=item *
-dTHR and djSP have been obsoleted; the former removed (because it's
-a no-op) and the latter replaced with dSP.
+scalar() now forces scalar context even when used in void context.
=item *
-Perl now uses system malloc instead of Perl malloc on all 64-bit
-platforms, and even in some not-always-64-bit platforms like AIX,
-IRIX, and Solaris. This change breaks backward compatibility but
-Perl's malloc has problems with large address spaces and also the
-speed of vendors' malloc is generally better in large address space
-machines (Perl's malloc is mostly tuned for space).
-
-=back
+SOCKS support is now much more robust.
-=head1 New Tests
+=item *
-Many new tests have been added. The most notable is probably the
-lib/1_compile: it is very notable because running it takes quite a
-long time -- it test compiles all the Perl modules in the distribution.
-Please be patient.
+sort() arguments are now compiled in the right wantarray context
+(they were accidentally using the context of the sort() itself).
+The comparison block is now run in scalar context, and the arguments
+to be sorted are always provided list context.
-=head1 Known Problems
+=item *
-Note that unlike other sections in this document (which describe
-changes since 5.7.0) this section is cumulative containing known
-problems for all the 5.7 releases.
+Changed the POSIX character class C<[[:space:]]> to include the (very
+rarely used) vertical tab character. Added a new POSIX-ish character
+class C<[[:blank:]]> which stands for horizontal whitespace
+(currently, the space and the tab).
-=head2 AIX vac 5.0.0.0 May Produce Buggy Code For Perl
+=item *
-The AIX C compiler vac version 5.0.0.0 may produce buggy code,
-resulting in few random tests failing, but when the failing tests
-are run by hand, they succeed. We suggest upgrading to at least
-vac version 5.0.1.0, that has been known to compile Perl correctly.
-"lslpp -L|grep vac.C" will tell you the vac version.
+The tainting behaviour of sprintf() has been rationalized. It does
+not taint the result of floating point formats anymore, making the
+behaviour consistent with that of string interpolation.
-=head2 lib/ftmp-security tests warn 'system possibly insecure'
+=item *
-Don't panic. Read INSTALL 'make test' section instead.
+Some cases of inconsistent taint propagation (such as within hash
+values) have been fixed.
-=head2 lib/io_multihomed Fails In LP64-Configured HP-UX
+=item *
-The lib/io_multihomed test may hang in HP-UX if Perl has been
-configured to be 64-bit. Because other 64-bit platforms do not hang in
-this test, HP-UX is suspect. All other tests pass in 64-bit HP-UX. The
-test attempts to create and connect to "multihomed" sockets (sockets
-which have multiple IP addresses).
+The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
+of simple pattern matches. These are now handled better.
-=head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX
+=item *
-If perl is configured with -Duse64bitall, the successful result of the
-subtest 10 of lib/posix may arrive before the successful result of the
-subtest 9, which confuses the test harness so much that it thinks the
-subtest 9 failed.
+Regular expression debug output (whether through C<use re 'debug'>
+or via C<-Dr>) now looks better.
-=head2 lib/b test 19
+=item *
-The test fails on various platforms (PA64 and IA64 are known), but the
-exact cause is still being investigated.
+Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
+bug has been fixed.
-=head2 Linux With Sfio Fails op/misc Test 48
+=item *
-No known fix.
+Use of $& could trigger a core dump under some situations. This
+is now avoided.
-=head2 sigaction test 13 in VMS
+=item *
-The test is known to fail; whether it's because of VMS of because
-of faulty test is not known.
+The regular expression captured submatches ($1, $2, ...) are now
+more consistently unset if the match fails, instead of leaving false
+data lying around in them.
-=head2 sprintf tests 129 and 130
+=item *
-The op/sprintf tests 129 and 130 are known to fail on some platforms.
-Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
-The failing platforms do not comply with the ANSI C Standard, line
-19ff on page 134 of ANSI X3.159 1989 to be exact. (They produce
-something else than "1" and "-1" when formatting 0.6 and -0.6 using
-the printf format "%.0f", most often they produce "0" and "-0".)
+readline() on files opened in "slurp" mode could return an extra "" at
+the end in certain situations. This has been corrected.
-=head2 Failure of Thread tests
+=item *
-The subtests 19 and 20 of lib/thr5005.t test are known to fail due to
-fundamental problems in the 5.005 threading implementation. These are
-not new failures--Perl 5.005_0x has the same bugs, but didn't have
-these tests. (Note that support for 5.005-style threading remains
-experimental.)
+Autovivification of symbolic references of special variables described
+in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
+again now.
-=head2 Localising a Tied Variable Leaks Memory
+=item *
- use Tie::Hash;
- tie my %tie_hash => 'Tie::StdHash';
+Sys::Syslog ignored the C<LOG_AUTH> constant.
- ...
+=item *
- local($tie_hash{Foo}) = 1; # leaks
+All but the first argument of the IO syswrite() method are now optional.
-Code like the above is known to leak memory every time the local()
-is executed.
+=item *
-=head2 Self-tying of Arrays and Hashes Is Forbidden
+$AUTOLOAD, sort(), lock(), and spawning subprocesses
+in multiple threads simultaneously are now thread-safe.
-Self-tying of arrays and hashes is broken in rather deep and
-hard-to-fix ways. As a stop-gap measure to avoid people from getting
-frustrated at the mysterious results (core dumps, most often) it is
-for now forbidden (you will get a fatal error even from an attempt).
+=item *
-=head2 Building Extensions Can Fail Because Of Largefiles
+Tie::ARRAY SPLICE method was broken.
-Some extensions like mod_perl are known to have issues with
-`largefiles', a change brought by Perl 5.6.0 in which file offsets
-default to 64 bits wide, where supported. Modules may fail to compile
-at all or compile and work incorrectly. Currently there is no good
-solution for the problem, but Configure now provides appropriate
-non-largefile ccflags, ldflags, libswanted, and libs in the %Config
-hash (e.g., $Config{ccflags_nolargefiles}) so the extensions that are
-having problems can try configuring themselves without the
-largefileness. This is admittedly not a clean solution, and the
-solution may not even work at all. One potential failure is whether
-one can (or, if one can, whether it's a good idea) link together at
-all binaries with different ideas about file offsets, all this is
-platform-dependent.
+=item *
-=head2 The Compiler Suite Is Still Experimental
+Allow read-only string on left hand side of non-modifying tr///.
-The compiler suite is slowly getting better but is nowhere near
-working order yet.
+=item *
-=head1 Security Vulnerability Closed
+Several Unicode fixes.
-(This change was already made in 5.7.0 but bears repeating here.)
+=over 8
-A security vulnerability affecting all Perl versions prior to 5.6.1
-was found in August 2000. The vulnerability does not affect default
-installations and as far as is known affects only the Linux platform.
+=item *
-You should upgrade your Perl to 5.6.1 as soon as possible. Patches
-for earlier releases exist but using the patches require full
-recompilation from the source code anyway, so 5.6.1 is your best
-choice.
+BOMs (byte order marks) in the beginning of Perl files
+(scripts, modules) should now be transparently skipped.
+UTF-16 (UCS-2) encoded Perl files should now be read correctly.
-See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
-for more information.
+=item *
-=head1 Incompatible Changes
+The character tables have been updated to Unicode 3.1.1.
-=head2 64-bit platforms and malloc
+=item *
-If your pointers are 64 bits wide, the Perl malloc is no more being
-used because it simply does not work with 8-byte pointers. Also,
-usually the system malloc on such platforms are much better optimized
-for such large memory models than the Perl malloc.
+Comparing with utf8 data does not magically upgrade non-utf8 data
+into utf8.
-=head2 AIX Dynaloading
+=item *
-The AIX dynaloading now uses in AIX releases 4.3 and newer the native
-dlopen interface of AIX instead of the old emulated interface. This
-change will probably break backward compatibility with compiled
-modules. The change was made to make Perl more compliant with other
-applications like modperl which are using the AIX native interface.
+C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
-=head2 Socket Extension Dynamic in VMS
+=item *
-The Socket extension is now dynamically loaded instead of being
-statically built in. This may or may not be a problem with ancient
-TCP/IP stacks of VMS: we do not know since we weren't able to test
-Perl in such configurations.
+Concatenation with the C<.> operator or via variable interpolation,
+C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
+substitution with C<s///>, single-quoted UTF8, should now work.
-=head2 Different Definition of the Unicode Character Classes \p{In...}
+=item *
-As suggested by the Unicode consortium, the Unicode character classes
-now prefer I<scripts> as opposed to I<blocks> (as defined by Unicode);
-in Perl, when the C<\p{In....}> and the C<\p{In....}> regular expression
-constructs are used. This has changed the definition of some of those
-character classes.
+The C<tr///> operator now works. Note that the C<tr///CU>
+functionality has been removed (but see pack('U0', ...)).
-The difference between scripts and blocks is that scripts are the
-glyphs used by a language or a group of languages, while the blocks
-are more artificial groupings of 256 characters based on the Unicode
-numbering.
+=item *
-In general this change results in more inclusive Unicode character
-classes, but changes to the other direction also do take place:
-for example while the script C<Latin> includes all the Latin
-characters and their various diacritic-adorned versions, it
-does not include the various punctuation or digits (since they
-are not solely C<Latin>).
+C<eval "v200"> now works.
-Changes in the character class semantics may have happened if a script
-and a block happen to have the same name, for example C<Hebrew>.
-In such cases the script wins and C<\p{InHebrew}> now means the script
-definition of Hebrew. The block definition in still available,
-though, by appending C<Block> to the name: C<\p{InHebrewBlock}> means
-what C<\p{InHebrew}> meant in perl 5.6.0. For the full list
-of affected character classes, see L<perlunicode/Blocks>.
+=item *
-=head2 Deprecations
+Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
+This has been corrected.
-The current user-visible implementation of pseudo-hashes (the weird
-use of the first array element) is deprecated starting from Perl 5.8.0
-and will be removed in Perl 5.10.0, and the feature will be
-implemented differently. Not only is the current interface rather
-ugly, but the current implementation slows down normal array and hash
-use quite noticeably. The C<fields> pragma interface will remain
-available.
+=item *
-The syntaxes C<@a->[...]> and C<@h->{...}> have now been deprecated.
+Zero entries were missing from the Unicode classes like C<IsDigit>.
-The suidperl is also considered to be too much a risk to continue
-maintaining and the suidperl code is likely to be removed in a future
-release.
+=back
-The C<package;> syntax (C<package> without an argument has been
-deprecated. Its semantics were never that clear and its
-implementation even less so. If you have used that feature to
-disallow all but fully qualified variables, C<use strict;> instead.
+=item *
-The chdir(undef) and chdir('') behaviors to match chdir() has been
-deprecated. In future versions, chdir(undef) and chdir('') will
-simply fail.
+Large unsigned numbers (those above 2**31) could sometimes lose their
+unsignedness, causing bogus results in arithmetic operations.
-=head1 Core Enhancements
+=back
-In general a lot of fixing has happened in the area of Perl's
-understanding of numbers, both integer and floating point. Since in
-many systems the standard number parsing functions like C<strtoul()>
-and C<atof()> seem to have bugs, Perl tries to work around their
-deficiencies. This results hopefully in more accurate numbers.
+=head2 Platform Specific Changes and Fixes
=over 4
=item *
-The rules for allowing underscores (underbars) in numeric constants
-have been relaxed and simplified: now you can have an underscore
-B<between digits>.
-
-=item *
+BSDI 4.*
-GMAGIC (right-hand side magic) could in many cases such as string
-concatenation be invoked too many times.
+Perl now works on post-4.0 BSD/OSes.
=item *
-Lexicals I: lexicals outside an eval "" weren't resolved
-correctly inside a subroutine definition inside the eval "" if they
-were not already referenced in the top level of the eval""ed code.
-
-=item *
+All BSDs
-Lexicals II: lexicals leaked at file scope into subroutines that
-were declared before the lexicals.
+Setting C<$0> now works (as much as possible; see L<perlvar> for details).
=item *
-Lvalue subroutines can now return C<undef> in list context.
-
-=item *
+Cygwin
-The C<op_clear> and C<op_null> are now exported.
+Numerous updates; currently synchronised with Cygwin 1.1.4.
=item *
-A new special regular expression variable has been introduced:
-C<$^N>, which contains the most-recently closed group (submatch).
+Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
=item *
-L<utime> now supports C<utime undef, undef, @files> to change the
-file timestamps to the current time.
-
-=item *
+EPOC
-The Perl parser has been stress tested using both random input and
-Markov chain input.
+EPOC update after Perl 5.6.0. See README.epoc.
=item *
-C<eval "v200"> now works.
-
-=item *
+FreeBSD 3.*
-VMS now works under PerlIO.
+Perl now works on post-3.0 FreeBSDs.
=item *
-END blocks are now run even if you exit/die in a BEGIN block.
-The execution of END blocks is now controlled by
-PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new
-behaviour for perl embedders. This will default in 5.10. See
-L<perlembed>.
-
-=back
-
-=head1 Modules and Pragmata
-
-=head2 New Modules and Distributions
+HP-UX
-=over 4
+README.hpux updated; C<Configure -Duse64bitall> now almost works.
=item *
-L<Attribute::Handlers> - Simpler definition of attribute handlers
-
-=item *
+IRIX
-L<ExtUtils::Constant> - generate XS code to import C header constants
+Numerous compilation flag and hint enhancements; accidental mixing
+of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
=item *
-L<I18N::Langinfo> - query locale information
+Linux
+
+=over 8
=item *
-L<I18N::LangTags> - functions for dealing with RFC3066-style language tags
+Long doubles should now work (see INSTALL).
=item *
-L<libnet> - a collection of perl5 modules related to network programming
+Linux previously had problems related to sockaddrlen when using
+accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
-Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
+=back
=item *
-L<List::Util> - selection of general-utility list subroutines
+MacOS Classic
+
+Compilation of the standard Perl distribution in MacOS Classic should
+now work if you have the Metrowerks development environment and
+the missing Mac-specific toolkit bits. Contact the macperl mailing
+list for details.
=item *
-L<Locale::Maketext> - framework for localization
+MPE/iX
+
+MPE/iX update after Perl 5.6.0. See README.mpeix.
=item *
-L<Memoize> - Make your functions faster by trading space for time
+NetBSD/sparc
+
+Perl now works on NetBSD/sparc.
=item *
-L<NEXT> - pseudo-class for method redispatch
+OS/2
+
+Now works with usethreads (see INSTALL).
=item *
-L<Scalar::Util> - selection of general-utility scalar subroutines
+Solaris
+
+64-bitness using the Sun Workshop compiler now works.
=item *
-L<Test::More> - yet another framework for writing test scripts
+Tru64 (aka Digital UNIX, aka DEC OSF/1)
+
+The operating system version letter now recorded in $Config{osvers}.
+Allow compiling with gcc (previously explicitly forbidden). Compiling
+with gcc still not recommended because buggy code results, even with
+gcc 2.95.2.
=item *
-L<Test::Simple> - Basic utilities for writing tests
+Unicos
+
+Fixed various alignment problems that lead into core dumps either
+during build or later; no longer dies on math errors at runtime;
+now using full quad integers (64 bits), previously was using
+only 46 bit integers for speed.
=item *
-L<Time::HiRes> - high resolution ualarm, usleep, and gettimeofday
+VMS
-=item *
+chdir() now works better despite a CRT bug; now works with MULTIPLICITY
+(see INSTALL); now works with Perl's malloc.
-L<Time::Piece> - Object Oriented time objects
+The tainting of C<%ENV> elements via C<keys> or C<values> was previously
+unimplemented. It now works as documented.
-(Previously known as L<Time::Object>.)
+The C<waitpid> emulation has been improved. The worst bug (now fixed)
+was that a pid of -1 would cause a wildcard search of all processes on
+the system. The most significant enhancement is that we can now
+usually get the completion status of a terminated process.
-=item *
+POSIX-style signals are now emulated much better on VMS versions prior
+to 7.0.
-L<Time::Seconds> - a simple API to convert seconds to other date values
+The C<system> function and backticks operator have improved
+functionality and better error handling.
=item *
-L<UnicodeCD> - Unicode Character Database
+Windows
-=back
+=over 8
-=head2 Updated And Improved Modules and Pragmata
+=item *
-=over 4
+accept() no longer leaks memory.
=item *
-L<B::Deparse> module has been significantly enhanced. It now
-can deparse almost all of the standard test suite (so that the
-tests still succeed). There is a make target "test.deparse"
-for trying this out.
+Borland C++ v5.5 is now a supported compiler that can build Perl.
+However, the generated binaries continue to be incompatible with those
+generated by the other supported compilers (GCC and Visual C++).
=item *
-L<Class::Struct> now assigns the array/hash element if the accessor
-is called with an array/hash element as the B<sole> argument.
+Better chdir() return value for a non-existent directory.
=item *
-L<Cwd> extension is now (even) faster.
+Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
=item *
-L<DB_File> extension has been updated to version 1.77.
+New %ENV entries now propagate to subprocesses.
=item *
-L<Fcntl>, L<Socket>, and L<Sys::Syslog> have been rewritten to use the
-new-style constant dispatch section (see L<ExtUtils::Constant>).
+Current directory entries in %ENV are now correctly propagated to child
+processes.
=item *
-L<File::Find> is now (again) reentrant. It also has been made
-more portable.
+$ENV{LIB} now used to search for libs under Visual C.
=item *
-L<File::Glob> now supports C<GLOB_LIMIT> constant to limit the
-size of the returned list of filenames.
+fork() emulation has been improved in various ways, but still continues
+to be experimental. See L<perlfork> for known bugs and caveats.
=item *
-L<IO::Socket::INET> now supports C<LocalPort> of zero (usually meaning
-that the operating system will make one up.)
+A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
=item *
-The L<vars> pragma now supports declaring fully qualified variables.
-(Something that C<our()> does not and will not support.)
-
-=back
+Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
+Other bugs in chdir() and Cwd::cwd() have also been fixed.
-=head1 Utility Changes
+=item *
-=over 4
+HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
=item *
-The F<emacs/e2ctags.pl> is now much faster.
+The makefiles now provide a single switch to bulk-enable all the features
+enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
=item *
-L<h2ph> now supports C trigraphs.
+Allow REG_EXPAND_SZ keys in the registry.
=item *
-L<h2xs> uses the new L<ExtUtils::Constant> module which will affect
-newly created extensions that define constants. Since the new code is
-more correct (if you have two constants where the first one is a
-prefix of the second one, the first constant B<never> gets defined),
-less lossy (it uses integers for integer constant, as opposed to the
-old code that used floating point numbers even for integer constants),
-and slightly faster, you might want to consider regenerating your
-extension code (the new scheme makes regenerating easy).
-L<h2xs> now also supports C trigraphs.
+Can now send() from all threads, not just the first one.
=item *
-L<libnetcfg> has been added to configure the libnet.
+Fake signal handling reenabled, bugs and all.
=item *
-The F<Pod::Html> (and thusly L<pod2html>) now allows specifying
-a cache directory.
-
-=back
+%SIG has been enabled under USE_ITHREADS, but its use is completely
+unsupported under all configurations.
-=head1 New Documentation
+=item *
-=over 4
+Less stack reserved per thread so that more threads can run
+concurrently. (Still 16M per thread.)
=item *
-L<Locale::Maketext::TPJ13> is an article about software localization,
-originally published in The Perl Journal #13, republished here with
-kind permission.
+C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
+(works better when perl is running as service).
=item *
-More README.$PLATFORM files have been converted into pod, which also
-means that they also be installed as perl$PLATFORM documentation
-files. The new files are L<perlapollo>, L<perlbeos>, L<perldgux>,
-L<perlhurd>, L<perlmint>, L<perlnetware>, L<perlplan9>, L<perlqnx>,
-and L<perltru64>.
+Better UNC path handling under ithreads.
=item *
-The F<Todo> and F<Todo-5.6> files have been merged into L<perltodo>.
+wait(), waitpid() and backticks now return the correct exit status under
+Windows 9x.
=item *
-Use of the F<gprof> tool to profile Perl has been documented in
-L<perlhack>. There is a make target "perl.gprof" for generating a
-gprofiled Perl executable.
+winsock handle leak fixed.
=back
-=head1 Installation and Configuration Improvements
+=back
-=head2 New Or Improved Platforms
+=head1 New or Changed Diagnostics
=over 4
=item *
-AIX should now work better with gcc, threads, and 64-bitness. Also the
-long doubles support in AIX should be better now. See L<perlaix>.
+All regular expression compilation error messages are now hopefully
+easier to understand both because the error message now comes before
+the failed regex and because the point of failure is now clearly
+marked by a C<E<lt>-- HERE> marker.
=item *
-AtheOS (http://www.atheos.cx/) is a new platform.
+The various "opened only for", "on closed", "never opened" warnings
+drop the C<main::> prefix for filehandles in the C<main> package,
+for example C<STDIN> instead of C<main::STDIN>.
=item *
-DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
+The "Unrecognized escape" warning has been extended to include C<\8>,
+C<\9>, and C<\_>. There is no need to escape any of the C<\w> characters.
=item *
-DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
+Two new debugging options have been added: if you have compiled your
+Perl with debugging, you can use the -DT and -DR options to trace
+tokenising and to add reference counts to displaying variables,
+respectively.
=item *
-Several MacOS (Classic) portability patches have been applied. We
-hope to get a fully working port by 5.8.0. (The remaining problems
-relate to the changed IO model of Perl.) See L<perlmacos>.
+If an attempt to use a (non-blessed) reference as an array index
+is made, a warning is given.
=item *
-MacOS X (or Darwin) should now be able to build Perl even on HFS+
-filesystems. (The case-insensitivity confused the Perl build process.)
+C<push @a;> and C<unshift @a;> (with no values to push or unshift)
+now give a warning. This may be a problem for generated and evaled
+code.
=item *
-NetWare from Novell is now supported. See L<perlnetware>.
+If you try to L<perlfunc/pack> a number less than 0 or larger than 255
+using the C<"C"> format you will get an optional warning. Similarly
+for the C<"c"> format and a number less than -128 or more than 127.
=item *
-The Amdahl UTS UNIX mainframe platform is now supported.
+Certain regex modifiers such as C<(?o)> make sense only if applied to
+the entire regex. You will an optional warning if you try to do otherwise.
-=back
+=item *
-=head2 Generic Improvements
+Using arrays or hashes as references (e.g. C<< %foo->{bar} >>
+has been deprecated for a while. Now you will get an optional warning.
-=over 4
+=back
-=item *
+=head1 Changed Internals
-In AFS installations one can configure the root of the AFS to be
-somewhere else than the default F</afs> by using the Configure
-parameter C<-Dafsroot=/some/where/else>.
+=over 4
=item *
-The version of Berkeley DB used when the Perl (and, presumably, the
-DB_File extension) was built is now available as
-C<@Config{qw(db_version_major db_version_minor db_version_patch)}>
-from Perl and as C<DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
-DB_VERSION_PATCH_CFG> from C.
+perlapi.pod (a companion to perlguts) now attempts to document the
+internal API.
=item *
-The Thread extension is now not built at all under ithreads
-(C<Configure -Duseithreads>) because it wouldn't work anyway (the
-Thread extension requires being Configured with C<-Duse5005threads>).
+You can now build a really minimal perl called microperl.
+Building microperl does not require even running Configure;
+C<make -f Makefile.micro> should be enough. Beware: microperl makes
+many assumptions, some of which may be too bold; the resulting
+executable may crash or otherwise misbehave in wondrous ways.
+For careful hackers only.
=item *
-The C<B::Deparse> compiler backend has been so significantly improved
-that almost the whole Perl test suite passes after being deparsed. A
-make target has been added to help in further testing: C<make test.deparse>.
-
-=back
-
-=head1 Selected Bug Fixes
-
-=over 5
+Added rsignal(), whichsig(), do_join(), op_clear, op_null,
+ptr_table_clear(), ptr_table_free(), sv_setref_uv(), and several UTF-8
+interfaces to the publicised API. For the full list of the available
+APIs see L<perlapi>.
=item *
-The autouse pragma didn't work for Multi::Part::Function::Names.
+Made possible to propagate customised exceptions via croak()ing.
=item *
-The behaviour of non-decimal but numeric string constants such as
-"0x23" was platform-dependent: in some platforms that was seen as 35,
-in some as 0, in some as a floating point number (don't ask). This
-was caused by Perl using the operating system libraries in a situation
-where the result of the string to number conversion is undefined: now
-Perl consistently handles such strings as zero in numeric contexts.
+Now xsubs can have attributes just like subs. (Well, at least the
+built-in attributes.)
=item *
-L<dprofpp> -R didn't work.
+dTHR and djSP have been obsoleted; the former removed (because it's
+a no-op) and the latter replaced with dSP.
=item *
-PERL5OPT with embedded spaces didn't work.
+PERL_OBJECT has been completely removed.
=item *
-L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
-
-=back
-
-=head2 Platform Specific Changes and Fixes
-
-=over 4
+The MAGIC constants (e.g. C<'P'>) have been macrofied
+(e.g. C<PERL_MAGIC_TIED>) for better source code readability
+and maintainability.
=item *
-Some versions of glibc have a broken modfl(). This affects builds
-with C<-Duselongdouble>. This version of Perl detects this brokenness
-and has a workaround for it. The glibc release 2.2.2 is known to have
-fixed the modfl() bug.
-
-=back
-
-=head1 New or Changed Diagnostics
-
-=over 4
+The regex compiler now maintains a structure that identifies nodes in
+the compiled bytecode with the corresponding syntactic features of the
+original regex expression. The information is attached to the new
+C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
+complete information.
=item *
-In the regular expression diagnostics the C<E<lt>E<lt> HERE> marker
-introduced in 5.7.0 has been changed to be C<E<lt>-- HERE> since too
-many people found the C<E<lt>E<lt>> to be too similar to here-document
-starters.
+The C code has been made much more C<gcc -Wall> clean. Some warning
+messages still remain in some platforms, so if you are compiling with
+gcc you may see some warnings about dubious practices. The warnings
+are being worked on.
=item *
-If you try to L<perlfunc/pack> a number less than 0 or larger than 255
-using the C<"C"> format you will get an optional warning. Similarly
-for the C<"c"> format and a number less than -128 or more than 127.
+F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
=item *
-Certain regex modifiers such as C<(?o)> make sense only if applied to
-the entire regex. You will an optional warning if you try to do otherwise.
+Documentation on how to use the Perl source repository has been added
+to F<Porting/repository.pod>.
=item *
-Using arrays or hashes as references (e.g. C<%foo->{bar}> has been
-deprecated for a while. Now you will get an optional warning.
+There are now several profiling make targets.
=back
-=head1 Source Code Enhancements
-
-=head2 MAGIC constants
-
-The MAGIC constants (e.g. C<'P'>) have been macrofied
-(e.g. C<PERL_MAGIC_TIED>) for better source code readability
-and maintainability.
-
-=head2 Better commented code
-
-F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
+=head1 Security Vulnerability Closed
-=head2 Regex pre-/post-compilation items matched up
+(This change was already made in 5.7.0 but bears repeating here.)
-The regex compiler now maintains a structure that identifies nodes in
-the compiled bytecode with the corresponding syntactic features of the
-original regex expression. The information is attached to the new
-C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
-complete information.
+A potential security vulnerability in the optional suidperl component
+of Perl was identified in August 2000. suidperl is neither built nor
+installed by default. As of November 2001 the only known vulnerable
+platform is Linux, most likely all Linux distributions. CERT and
+various vendors and distributors have been alerted about the vulnerability.
+See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
+for more information.
-=head2 gcc -Wall
+The problem was caused by Perl trying to report a suspected security
+exploit attempt using an external program, /bin/mail. On Linux
+platforms the /bin/mail program had an undocumented feature which
+when combined with suidperl gave access to a root shell, resulting in
+a serious compromise instead of reporting the exploit attempt. If you
+don't have /bin/mail, or if you have 'safe setuid scripts', or if
+suidperl is not installed, you are safe.
-The C code has been made much more C<gcc -Wall> clean. Some warning
-messages still remain, though, so if you are compiling with gcc you
-will see some warnings about dubious practices. The warnings are
-being worked on.
+The exploit attempt reporting feature has been completely removed from
+Perl 5.8.0 (and the maintenance release 5.6.1, and it was removed also
+from all the Perl 5.7 releases), so that particular vulnerability
+isn't there anymore. However, further security vulnerabilities are,
+unfortunately, always possible. The suidperl functionality is most
+probably going to be removed in Perl 5.10. In any case, suidperl
+should only be used by security experts who know exactly what they are
+doing and why they are using suidperl instead of some other solution
+such as sudo (see http://www.courtesan.com/sudo/).
=head1 New Tests
-Several new tests have been added, especially for the F<lib> subsection.
+Several new tests have been added, especially for the F<lib>
+subsection. There are now about 34 000 individual tests (spread over
+about 530 test scripts), in the regression suite (5.6.1 has about
+11700 tests, in 258 test scripts) Many of the new tests are introduced
+by the new modules, but still in general Perl is now more thoroughly
+tested.
+
+Because of the large number of tests, running the regression suite
+will take considerably longer time than it used to: expect the suite
+to take up to 4-5 times longer to run than in perl 5.6. In a really
+fast machine you can hope to finish the suite in about 5 minutes
+(wallclock time).
The tests are now reported in a different order than in earlier Perls.
(This happens because the test scripts from under t/lib have been moved
=head1 Known Problems
-Note that unlike other sections in this document (which describe
-changes since 5.7.0) this section is cumulative containing known
-problems for all the 5.7 releases.
-
=head2 AIX
=over 4
=head2 Amiga Perl Invoking Mystery
One cannot call Perl using the C<volume:> syntax, that is, C<perl -v>
-works, but for example C<bin:perl -v> doesn't. The exact reason is
+works, but for example C<bin:perl -v> doesn't. The exact reason isn't
known but the current suspect is the F<ixemul> library.
=head2 lib/ftmp-security tests warn 'system possibly insecure'
No known fix.
+=head2 Mac OS X
+
+The following tests are known to fail:
+
+ Failed Test Stat Wstat Total Fail Failed List of Failed
+ -------------------------------------------------------------------------
+ ../ext/DB_File/t/db-btree.t 0 11 ?? ?? % ??
+ ../ext/DB_File/t/db-recno.t 149 3 2.01% 61 63 65
+ ../ext/POSIX/t/posix.t 31 1 3.23% 10
+ ../lib/warnings.t 450 1 0.22% 316
+
=head2 OS/390
OS/390 has rather many test failures but the situation is actually
=head2 Failure of Thread tests
-B<Note that support for 5.005-style threading remains experimental.>
+B<Note that support for 5.005-style threading remains experimental
+and practically unsupported.>
The following tests are known to fail due to fundamental problems in
the 5.005 threading implementation. These are not new failures--Perl
5.005_0x has the same bugs, but didn't have these tests.
- lib/autouse.t 4
- t/lib/thr5005.t 19-20
+ ext/List/Util/t/first 2
+ lib/autouse 4
+ ext/Thread/thr5005 19-20
+
+These failures are unlikely to get fixed.
=head2 UNICOS
=head2 VMS
-Rather many tests are failing in VMS but that actually more tests
-succeed in VMS than they used to, it's just that there are many,
-many more tests than there used to be.
-
-Here are the known failures from some compiler/platform combinations.
-
-DEC C V5.3-006 on OpenVMS VAX V6.2
-
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.ext.posix]sigaction..................FAILED on test 7
- [-.ext.time.hires]hires.................FAILED on test 14
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.math.bigint.t]bigintpm...........FAILED on test 1183
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- [.op]sprintf............................FAILED on test 12
- Failed 8/399 tests, 91.23% okay.
-
-DEC C V6.0-001 on OpenVMS Alpha V7.2-1 and
-Compaq C V6.2-008 on OpenVMS Alpha V7.1
-
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- Failed 4/399 tests, 92.48% okay.
-
-Compaq C V6.4-005 on OpenVMS Alpha 7.2.1
-
- [-.ext.b]showlex........................FAILED on test 1
- [-.ext.list.util.t]tainted..............FAILED on test 3
- [-.lib.file.find]taint..................FAILED on test 17
- [-.lib.test.simple.t]exit...............FAILED on test 1
- [.lib]vmsish............................FAILED on test 13
- [.op]misc...............................FAILED on test 49
- Failed 6/401 tests, 92.77% okay.
+There is one known test failure with a default configuration:
+
+ [.run]switches..........................FAILED on test 1
=head2 Win32
Code like the above is known to leak memory every time the local()
is executed.
+=head2 Localising Tied Arrays and Hashes Is Broken
+
+ local %tied_array;
+
+doesn't work as one would expect: the old value is restored
+incorrectly.
+
=head2 Self-tying of Arrays and Hashes Is Forbidden
Self-tying of arrays and hashes is broken in rather deep and
frustrated at the mysterious results (core dumps, most often) it is
for now forbidden (you will get a fatal error even from an attempt).
-=head2 Variable Attributes are not Currently Usable for Tieing
-
-This limitation will hopefully be fixed in future. (Subroutine
-attributes work fine for tieing, see L<Attribute::Handlers>).
-
=head2 Building Extensions Can Fail Because Of Largefiles
Some extensions like mod_perl are known to have issues with
all binaries with different ideas about file offsets, all this is
platform-dependent.
+=head2 Unicode Support on EBCDIC Still Spotty
+
+Though mostly working, Unicode support still has problem spots on
+EBCDIC platforms. One such known spot are the C<\p{}> and C<\P{}>
+regular expression constructs for code points less than 256: the
+pP are testing for Unicode code points, not knowing about EBCDIC.
+
=head2 The Compiler Suite Is Still Experimental
-The compiler suite is slowly getting better but is nowhere near
-working order yet.
+The compiler suite is slowly getting better but it continues to be
+highly experimental. Use in production environments is discouraged.
-=head2 The Long Double Support is Still Experimental
+=head2 The Long Double Support Is Still Experimental
The ability to configure Perl's numbers to use "long doubles",
floating point numbers of hopefully better accuracy, is still
operations are more likely to be executed by less optimised
libraries).
+=head2 Seen In Perl 5.7 But Gone Now
+
+Some modules were seen in the Perl 5.7 development releases
+but are not present in 5.8.0.
+
+=over 4
+
+=item *
+
+C<Attribute::Handlers> was removed because the implementation of C<my>
+variable attributes changed so much that the Attribute::Handlers will
+require a major rewrite. (This means that you can't use
+Attribute::Handler 0.76 with Perl 5.8.0.)
+
+=item *
+
+C<Time::Piece> (previously known as C<Time::Object>) was removed
+because it was felt that it didn't have enough value in it to be a
+core module. It is still a useful module, though, and is available
+from the CPAN.
+
+=back
+
=head1 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.com/perl/, the Perl Home Page.
+information at http://www.perl.com/, the Perl Home Page.
If you believe you have an unreported bug, please run the B<perlbug>
program included with your release. Be sure to trim your bug down