=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
+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.
-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.
+If you are upgrading from Perl 5.005_03, you might also want
+to read L<perl56delta>.
-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.
+=head1 Highlights In 5.8.0
-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/).
+=over 4
-=head1 Incompatible Changes
+=item *
-=over 4
+Better Unicode support
=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>.
+New Thread Implementation
=item *
-The semantics of bless(REF, REF) were unclear and until someone proves
-it to make some sense, it is forbidden.
+Many New Modules
+
+=item *
+
+Better Numeric Accuracy
=item *
-A reference to a reference now stringify as "REF(0x81485ec)" instead
+Safe Signals
+
+=item *
+
+More Extensive Regression Testing
+
+=back
+
+=head1 Incompatible Changes
+
+=head2 64-bit platforms and malloc
+
+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.
+
+=head2 AIX Dynaloading
+
+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.
+
+=head2 Attributes for C<my> variables now handled at run-time.
+
+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).
+
+=head2 Socket Extension Dynamic in VMS
+
+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.
+
+=head2 IEEE-format Floating Point Default on OpenVMS Alpha
+
+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.
+
+=head2 New Unicode Properties
+
+Unicode I<scripts> are now supported. Scripts are similar to (and superior
+to) Unicode I<blocks>. 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 (mostly) 256 characters based
+on the Unicode numbering.
+
+In general, scripts are more inclusive, but not universally so. 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>).
+
+A number of other properties are now supported, including C<\p{L&}>,
+C<\p{Any}> C<\p{Assigned}>, C<\p{Unassigned}>, C<\p{Blank}> and
+C<\p{SpacePerl}> (along with their C<\P{...}> versions, of course).
+See L<perlunicode> for details, and more additions.
+
+The C<In> or C<Is> prefix to names used with the C<\p{...}> and C<\P{...}>
+are now almost always optional. The only exception is that a C<In> prefix
+is required to signify a Unicode block when a block name conflicts with a
+script name. For example, C<\p{Tibetan}> refers to the script, while
+C<\p{InTibetan}> refers to the block. When there is no name conflict, you
+can omit the C<In> from the block name (e.g. C<\p{BraillePatterns}>), but
+to be safe, it's probably best to always use the C<In>).
+
+=head2 Perl Parser Stress Tested
+
+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.
+
+=head2 REF(...) Instead Of SCALAR(...)
+
+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().
+=head2 Deprecations
+
+=over 4
+
=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.
+The semantics of bless(REF, REF) were unclear and until someone proves
+it to make some sense, it is forbidden.
=item *
=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.
+The builtin dump() function has probably outlived most of its
+usefulness. The core-dumping functionality will remain in future
+available as an explicit call to C<CORE::dump()>, but in future
+releases the behaviour of an unqualified C<dump()> call may change.
+
+=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.
=item *
=item *
-lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
-In future releases this may become a fatal error.
+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 *
-The long deprecated uppercase aliases for the string comparison
-operators (EQ, NE, LT, LE, GE, GT) have now been removed.
+Spurious syntax errors generated in certain situations, when glob()
+caused File::Glob to be loaded for the first time, have been fixed.
=item *
-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.
+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 *
-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
+lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
+In future releases this may become a fatal error.
-=head1 Core Enhancements
+=item *
-=over 4
+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 *
-C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
-in multiple arguments.)
+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 *
-my __PACKAGE__ $obj now works.
+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 *
-C<no Module;> now works even if there is no "sub unimport" in the Module.
+The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
=item *
-The numerical comparison operators return C<undef> if either operand
-is a NaN. Previously the behaviour was unspecified.
+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<pack('U0a*', ...)> can now be used to force a string to UTF8.
+The long deprecated uppercase aliases for the string comparison
+operators (EQ, NE, LT, LE, GE, GT) have now been removed.
=item *
-prototype(\&) is now available.
+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', ...).
=item *
-There is now an UNTIE method.
+Earlier Perls treated "sub foo (@bar)" as equivalent to "sub foo (@)".
+The prototypes are now checked at compile-time for invalid characters.
+An optional warning is generated ("Illegal character in prototype...")
+but this may be upgraded to a fatal error in a future release.
=back
-=head1 Modules and Pragmata
+=head1 Core Enhancements
-=head2 New Modules
+=head2 PerlIO is Now The Default
=over 4
=item *
-File::Temp allows one to create temporary files and directories in an
-easy, portable, and secure way.
-
-=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:
-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.
+ open($fh,'>:crlf :utf8', $path) || ...
-=back
+or on already opened handles via extended C<binmode>:
-=head2 Updated And Improved Modules and Pragmata
+ binmode($fh,':encoding(iso-8859-7)');
-=over 4
+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).
-=item *
+Layers to be applied by default may be specified via the 'open' pragma.
-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.
+See L</"Installation and Configuration Improvements"> for the effects
+of PerlIO on your architecture name.
=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.
+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($fh,">:utf8","Uni.txt");
-The attributes::reftype() now works on tied arguments.
+Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
+for you since it's not UTF-8 what you will be getting but instead
+UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
+http://www.unicode.org/unicode/reports/tr16/ for more information.
+In future releases this naming may change.
=item *
-AutoLoader can now be disabled with C<no AutoLoader;>,
+File handles can translate character encodings from/to Perl's internal
+Unicode form on read/write via the ":encoding()" layer.
=item *
-The English module can now be used without the infamous performance
-hit by saying
-
- use English '-no_performance_hit';
+File handles can be opened to "in memory" files held in Perl scalars via:
-(Assuming, of course, that one doesn't need the troublesome variables
-C<$`>, C<$&>, or C<$'>.) Also, introduced C<@LAST_MATCH_START> and
-C<@LAST_MATCH_END> English aliases for C<@-> and C<@+>.
+ open($fh,'>', \$variable) || ...
=item *
-File::Find now has pre- and post-processing callbacks. It also
-correctly changes directories when chasing symbolic links. Callbacks
-(naughtily) exiting with "next;" instead of "return;" now work.
+Anonymous temporary files are available without need to
+'use FileHandle' or other module via
-=item *
+ open($fh,"+>", undef) || ...
-File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
-prototype mismatch with CORE::glob().
+That is a literal undef, not an undefined value.
=item *
-IPC::Open3 now allows the use of numeric file descriptors.
+The list form of C<open> is now implemented for pipes (at least on UNIX):
-=item *
+ open($fh,"-|", 'cat', '/etc/motd')
-use lib now works identically to @INC. Removing directories
-with 'no lib' now works.
+creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
+the child process.
-=item *
+=back
-C<%INC> now localised in a Safe compartment so that use/require work.
+=head2 Safe Signals
-=item *
+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).
-The Shell module now has an OO interface.
+This change may have surprising side effects because signals no longer
+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.
-=back
+=head2 Unicode Overhaul
-=head1 Utility Changes
+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 *
-The Emacs perl mode (emacs/cperl-mode.el) has been updated to version
-4.31.
+The Unicode Character Database coming with Perl has been upgraded
+to Unicode 3.1.1. For more information, see http://www.unicode.org/.
=item *
-Perlbug is now much more robust. It also sends the bug report to
-perl.org, not perl.com.
+For developers interested in enhancing Perl's Unicode capabilities:
+almost all the UCD files are included with the Perl distribution in
+the F<lib/unicore subdirectory>. The most notable omission, for space
+considerations, is the Unihan database.
=item *
-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.
-
-=item *
+The properties \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.)
-The xsubpp utility for extension writers now understands POD
-documentation embedded in the *.xs files.
+See "New Unicode Properties" earlier in this document for additional
+information on changes with Unicode properties.
=back
-=head1 New Documentation
+=head2 Understanding of Numbers
+
+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.
+
+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.)
+
+=head2 Miscellaneous Changes
=over 4
=item *
-perl56delta details the changes between the 5.005 release and the
-5.6.0 release.
+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 *
-perldebtut is a Perl debugging tutorial.
+C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
+in multiple arguments.)
=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.
+The builtin dump() now gives an optional warning
+C<Ambiguous call resolved as CORE::dump(), qualify as such or use &>
+meaning that by default C<dump(...)> is resolved as the builtin
+dump() which dumps core and aborts, not as (possibly) user-defined
+C<sub dump>. To call the latter, qualify the call as C<&dump(...)>.
+(The whole dump() feature is to considered deprecated, and possibly
+removed/changed in future releases.)
=item *
-perlnewmod tells about writing and submitting a new module.
+chomp() and chop() have been demoted back to I<not> being overrideable
+because they cannot really be overridden-- the problem is that their
+prototype cannot be expressed and therefore one really cannot write
+replacements to override these builtins.
=item *
-perlposix-bc explains using Perl on the POSIX-BC platform
-(an EBCDIC mainframe platform).
+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 *
-perlretut is a regular expression tutorial.
+Formats now support zero-padded decimal fields.
=item *
-perlrequick is a regular expressions quick-start guide.
-Yes, much quicker than perlretut.
+Lvalue subroutines can now return C<undef> in list context.
+However, the lvalue subroutine feature still remains experimental.
=item *
-perlutil explains the command line utilities packaged with the Perl
-distribution.
-
-=back
+A lost warning "Can't declare ... dereference in my" has been
+restored (Perl had it earlier but it became lost in later releases.)
-=head1 Performance Enhancements
+=item *
-=over 4
+A new special regular expression variable has been introduced:
+C<$^N>, which contains the most-recently closed group (submatch).
=item *
-map() that changes the size of the list should now work faster.
+C<no Module;> now works even if there is no "sub unimport" in the Module.
=item *
-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).
+The numerical comparison operators return C<undef> if either operand
+is a NaN. Previously the behaviour was unspecified.
-=back
+=item *
-=head1 Installation and Configuration Improvements
+The following builtin functions are now overridable: each(), keys(),
+pop(), push(), shift(), splice(), unshift().
-=head2 Generic Improvements
+=item *
-=over 4
+C<pack('U0a*', ...)> can now be used to force a string to UTF8.
=item *
-INSTALL now explains how you can configure Perl to use 64-bit
-integers even on non-64-bit platforms.
+my __PACKAGE__ $obj now works.
=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.
+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";
-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.
+will print "bar foo\n". This feature helps in writing
+internationalised software, and in general when the order
+of the parameters can vary.
=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.
+prototype(\&) is now available.
=item *
-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.
+prototype(\[$@%&]) is now available to implicitly create references
+(useful for example if you want to emulate the tie() interface).
=item *
-If binary compatibility with the 5.005 release is not wanted, Configure
-no longer suggests including the 5.005 modules in @INC.
+A new command-line option, C<-t> is available. It is the
+little brother of C<-T>: instead of dieing on taint violations,
+lexical warnings are given. B<This is only meant as a temporary
+debugging aid while securing the code of old legacy applications.
+This is not a substitute for -T.>
=item *
-Configure C<-S> can now run non-interactively.
+If tr/// is just counting characters, it doesn't attempt to
+modify its target.
=item *
-configure.gnu now works with options with whitespace in them.
+untie() will now call an UNTIE() hook if it exists. See L<perltie>
+for details.
=item *
-installperl now outputs everything to STDERR.
+L<utime> now supports C<utime undef, undef, @files> to change the
+file timestamps to the current time.
=item *
-$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.)
+The rules for allowing underscores (underbars) in numeric constants
+have been relaxed and simplified: now you can have an underscore
+simply B<between digits>.
=back
-=head1 Selected Bug Fixes
+=head1 Modules and Pragmata
+
+=head2 New Modules and Pragmata
=over 4
=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.
+C<Attribute::Handlers> allows a class to define attribute handlers.
-=item *
+ package MyPack;
+ use Attribute::Handlers;
+ sub Wolf :ATTR(SCALAR) { print "howl!\n" }
-C<*foo{FORMAT}> now works.
+ # later, in some package using or inheriting from MyPack...
-=item *
+ my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
-Lexical warnings now propagating correctly between scopes.
+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 *
-Line renumbering with eval and C<#line> now works.
+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 *
-Fixed numerous memory leaks, especially in eval "".
+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 *
-Modulus of unsigned numbers now works (4063328477 % 65535 used to
-return 27406, instead of 27047).
+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 *
-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<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 *
-our() variables will not cause "will not stay shared" warnings.
+C<Digest>, frontend module for calculating digests (checksums), from
+Gisle Aas, has been added. See L<Digest>.
=item *
-pack "Z" now correctly terminates the string with "\0".
+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';
-Fix password routines which in some shadow password platforms
-(e.g. HP-UX) caused getpwent() to return every other entry.
+ $digest = md5_hex("Thirsty Camel");
-=item *
+ print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
-printf() no longer resets the numeric locale to "C".
+NOTE: the C<MD5> backward compatibility module is deliberately not
+included since its further use is discouraged.
=item *
-C<q(a\\b)> now parses correctly as C<'a\\b'>.
+C<Encode>, by Nick Ing-Simmons, provides a mechanism to translate
+between different character encodings. Support for Unicode,
+ISO-8859-*, ASCII, CP*, KOI8-R, and three variants of EBCDIC are
+compiled in to the module. Several other encodings (like Japanese,
+Chinese, and MacIntosh encodings) are included and will be loaded at
+runtime. See L<Encode>.
+
+Any encoding supported by Encode module is also available to the
+":encoding()" layer if PerlIO is used.
=item *
-Printing quads (64-bit integers) with printf/sprintf now works
-without the q L ll prefixes (assuming you are on a quad-capable platform).
+C<I18N::Langinfo> can be use to query locale information.
+See L<I18N::Langinfo>.
=item *
-Regular expressions on references and overloaded scalars now work.
+C<I18N::LangTags> has functions for dealing with RFC3066-style
+language tags, by Sean Burke. See L<I18N::LangTags>.
=item *
-scalar() now forces scalar context even when used in void context.
+C<ExtUtils::Constant> is a new tool for extension writers for
+generating XS code to import C header constants, by Nicholas Clark.
+See L<ExtUtils::Constant>.
=item *
-sort() arguments are now compiled in the right wantarray context
-(they were accidentally using the context of the sort() itself).
+C<Filter::Simple> is an easy-to-use frontend to Filter::Util::Call,
+from Damian Conway. See L<Filter::Simple>.
-=item *
+ # in MyFilter.pm:
-Changed the POSIX character class C<[[:space:]]> to include the (very
-rare) vertical tab character. Added a new POSIX-ish character class
-C<[[:blank:]]> which stands for horizontal whitespace (currently,
-the space and the tab).
+ package MyFilter;
-=item *
+ use Filter::Simple sub {
+ while (my ($from, $to) = splice @_, 0, 2) {
+ s/$from/$to/g;
+ }
+ };
-$AUTOLOAD, sort(), lock(), and spawning subprocesses
-in multiple threads simultaneously are now thread-safe.
+ 1;
-=item *
+ # in user's code:
-Allow read-only string on left hand side of non-modifying tr///.
+ 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"
-Several Unicode fixes (but still not perfect).
+ no MyFilter;
-=over 8
+ print "red\n"; # this code is not filtered, will print "red\n"
=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.
+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 *
-The character tables have been updated to Unicode 3.0.1.
+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 *
-chr() for values greater than 127 now create utf8 when under use
-utf8.
+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>.
+
+Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
=item *
-Comparing with utf8 data does not magically upgrade non-utf8 data into
-utf8.
+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 *
-C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
+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;
-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.
+ $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>.
=item *
-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', ...)).
+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 *
-vec() now refuses to deal with characters >255.
+C<Memoize> can make your functions faster by trading space for time,
+from Mark-Jason Dominus. See L<Memoize>.
=item *
-Zero entries were missing from the Unicode classes like C<IsDigit>.
+C<MIME::Base64> allows you to encode data in base64, from Gisle Aas,
+as defined in RFC 2045 - I<MIME (Multipurpose Internet Mail
+Extensions)>.
-=back
+ use MIME::Base64;
-=item *
+ $encoded = encode_base64('Aladdin:open sesame');
+ $decoded = decode_base64($encoded);
-UNIVERSAL::isa no longer caches methods incorrectly. (This broke
-the Tk extension with 5.6.0.)
+ print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
-=back
+See L<MIME::Base64>.
-=head2 Platform Specific Changes and Fixes
+=item *
-=over 4
+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.
-=item *
+ use MIME::QuotedPrint;
-BSDI 4.*
+ $encoded = encode_qp("Smiley in Unicode: \x{263a}");
+ $decoded = decode_qp($encoded);
-Perl now works on post-4.0 BSD/OSes.
+ print $encoded, "\n"; # "Smiley in Unicode: =263A"
-=item *
+MIME::QuotedPrint has been enhanced to provide the basic methods
+necessary to use it with PerlIO::Via as in :
-All BSDs
+ use MIME::QuotedPrint;
+ open($fh,">Via(MIME::QuotedPrint)",$path);
-Setting C<$0> now works (as much as possible; see perlvar for details).
+See L<MIME::QuotedPrint>.
=item *
-Cygwin
-
-Numerous updates; currently synchronised with Cygwin 1.1.4.
+C<NEXT> is pseudo-class for method redispatch, from Damian Conway.
+See L<NEXT>.
=item *
-EPOC
-
-EPOC update after Perl 5.6.0. See README.epoc.
+C<open> is a new pragma for setting the default I/O disciplines
+for open().
=item *
-FreeBSD 3.*
-
-Perl now works on post-3.0 FreeBSDs.
+C<PerlIO::Scalar> provides the implementation of IO to "in memory"
+Perl scalars as discussed above, from Nick Ing-Simmons. It also
+serves as an example of a loadable PerlIO layer. Other future
+possibilities include PerlIO::Array and PerlIO::Code.
+See L<PerlIO::Scalar>.
=item *
-HP-UX
+C<PerlIO::Via> acts as a PerlIO layer and wraps PerlIO layer
+functionality provided by a class (typically implemented in perl
+code), from Nick Ing-Simmons.
-README.hpux updated; C<Configure -Duse64bitall> now almost works.
+ use MIME::QuotedPrint;
+ open($fh,">Via(MIME::QuotedPrint)",$path);
-=item *
+This will automatically convert everything output to C<$fh>
+to Quoted-Printable. See L<PerlIO::Via>.
-IRIX
+=item *
-Numerous compilation flag and hint enhancements; accidental mixing
-of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
+C<Pod::ParseLink>, by Russ Allbery, has been added,
+to parse LZ<><> links in pods as described in the new
+perlpodspec.
=item *
-Linux
-
-Long doubles should now work (see INSTALL).
+C<Pod::Text::Overstrike>, by Joe Smith, has been added.
+It converts POD data to formatted overstrike text.
+See L<Pod::Text::Overstrike>.
=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<Scalar::Util> is a selection of general-utility scalar subroutines,
+like blessed(), reftype(), and tainted(). See L<Scalar::Util>.
=item *
-MPE/iX
-
-MPE/iX update after Perl 5.6.0. See README.mpeix.
+C<sort> is a new pragma for controlling the behaviour of sort().
=item *
-NetBSD/sparc
-
-Perl now works on NetBSD/sparc.
+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 *
-OS/2
+C<Switch>, from Damian Conway, has been added. Just by saying
-Now works with usethreads (see INSTALL).
+ use Switch;
-=item *
+you have C<switch> and C<case> available in Perl.
-Solaris
+ use Switch;
-64-bitness using the Sun Workshop compiler now works.
+ switch ($val) {
+
+ 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" }
+ }
+
+See L<Switch>.
=item *
-Tru64 (aka Digital UNIX, aka DEC OSF/1)
+C<Test::More> is yet another framework for writing test scripts,
+more extensive than Test::Simple, by Michael Schwern. See L<Test::More>.
-The operating system version letter now recorded in $Config{osvers}.
-Allow compiling with gcc (previously explicitly forbidden). Compiling
-with gcc still not recommended because buggy code results, even with
-gcc 2.95.2.
+=item *
+
+C<Test::Simple> has basic utilities for writing tests, by Michael
+Schwern. See L<Test::Simple>.
=item *
-Unicos
+C<Text::Balanced> has been added, for extracting delimited text
+sequences from strings, from Damian Conway.
-Fixed various alignment problems that lead into core dumps either
-during build or later; no longer dies on math errors at runtime;
-now using full quad integers (64 bits), previously was using
-only 46 bit integers for speed.
+ use Text::Balanced 'extract_delimited';
-=item *
+ ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
-VMS
+$a will be "'never say never'", $b will be ', he never said'.
-chdir() now works better despite a CRT bug; now works with MULTIPLICITY
-(see INSTALL); now works with Perl's malloc.
+In addition to extract_delimited() there are also extract_bracketed(),
+extract_quotelike(), extract_codeblock(), extract_variable(),
+extract_tagged(), extract_multiple(), gen_delimited_pat(), and
+gen_extract_tagged(). With these you can implement rather advanced
+parsing algorithms. See L<Text::Balanced>.
=item *
-Windows
+C<threads> is an interface to interpreter threads, by Arthur Bergman.
+Interpreter threads (ithreads) is the new thread model introduced in
+Perl 5.6 but only available as an internal interface for extension
+writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
-=over 8
+=item *
+
+C<threads::shared> allows data sharing for interpreter threads, from
+Arthur Bergman. In the ithreads model any data sharing between
+threads must be explicit, as opposed to the old 5.005 thread model
+where data sharing was implicit. See L<threads::shared>.
=item *
-accept() no longer leaks memory.
+C<Tie::RefHash::Nestable>, by Edward Avis, allows storing hash
+references (unlike the standard Tie::RefHash) The module is contained
+within Tie::RefHash, see L<Tie::RefHash>.
=item *
-Better chdir() return value for a non-existent directory.
+C<Time::HiRes> provides high resolution timing (ualarm, usleep,
+and gettimeofday), from Douglas E. Wegscheid. See L<Time::HiRes>.
=item *
-New %ENV entries now propagate to subprocesses.
+C<Unicode::UCD> offers a querying interface to the Unicode Character
+Database. See L<Unicode::UCD>.
=item *
-$ENV{LIB} now used to search for libs under Visual C.
+C<Unicode::Collate> implements the UCA (Unicode Collation Algorithm)
+for sorting Unicode strings, by SADAHIRO Tomoyuki. See L<Unicode::Collate>.
=item *
-A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
+C<Unicode::Normalize> implements the various Unicode normalization
+forms, by SADAHIRO Tomoyuki. See L<Unicode::Normalize>.
=item *
-Allow REG_EXPAND_SZ keys in the registry.
+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.
+
+=back
+
+=head2 Updated And Improved Modules and Pragmata
+
+=over 4
=item *
-Can now send() from all threads, not just the first one.
+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.
=item *
-Fake signal handling reenabled, bugs and all.
+The attributes::reftype() now works on tied arguments.
=item *
-Less stack reserved per thread so that more threads can run
-concurrently. (Still 16M per thread.)
+AutoLoader can now be disabled with C<no AutoLoader;>.
=item *
-C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
-(works better when perl is running as service).
+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 *
-Better UNC path handling under ithreads.
+Class::Struct can now define the classes in compile time.
=item *
-wait() and waitpid() now work much better.
+Class::Struct now assigns the array/hash element if the accessor
+is called with an array/hash element as the B<sole> argument.
=item *
-winsock handle leak fixed.
+Data::Dumper has now an option to sort hashes.
-=back
+=item *
-=back
+Data::Dumper has now an option to dump code references
+using B::Deparse.
-=head1 New or Changed Diagnostics
+=item *
-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.
+DB_File now supports newer Berkeley DB versions, among
+other improvements.
-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>.
+=item *
-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.
+The English module can now be used without the infamous performance
+hit by saying
-=head1 Changed Internals
+ use English '-no_performance_hit';
-=over 4
+(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<@+>.
=item *
-perlapi.pod (a companion to perlguts) now attempts to document the
-internal API.
+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.
=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.
+File::Find now chdir()s correctly when chasing symbolic links.
=item *
-Added rsignal(), whichsig(), do_join() to the publicised API.
+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 *
-Made possible to propagate customised exceptions via croak()ing.
+File::Find is now (again) reentrant. It also has been made
+more portable.
=item *
-Added is_utf8_char(), is_utf8_string(), bytes_to_utf8(), and utf8_to_bytes().
+File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
+prototype mismatch with CORE::glob().
=item *
-Now xsubs can have attributes just like subs.
+File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
+the returned list of filenames.
-=back
+=item *
-=head1 Known Problems
+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).
-=head2 Unicode Support Still Far From Perfect
+=item *
-We're working on it. Stay tuned.
+IPC::Open3 now allows the use of numeric file descriptors.
-=head2 EBCDIC Still A Lost Platform
+=item *
-The plan is to bring them back.
+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.
-=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.
+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.
+
+=item *
-=head2 ftmp-security tests warn 'system possibly insecure'
+IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
+that the operating system will make one up.)
-Don't panic. Read INSTALL 'make test' section instead.
+=item *
-=head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX
+use lib now works identically to @INC. Removing directories
+with 'no lib' now works.
-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.
+=item *
-=head2 Long Doubles Still Don't Work In Solaris
+ExtUtils::MakeMaker now uses File::Spec internally, which hopefully
+leads into better portability.
-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.)
+=item *
-=head2 Linux With Sfio Fails op/misc Test 48
+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.
-No known fix.
+=item *
-=head2 Storable tests fail in some platforms
+Math::Complex handles inf, NaN etc., better.
-If any Storable tests fail the use of Storable is not advisable.
+=item *
-=over 4
+Net::Ping has been muchly enhanced. Multihoming is now supported.
+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 *
-Many Storable tests fail on AIX configured with 64 bit integers.
+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.
+
+=item *
-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.
+In Safe the C<%INC> now localised in a Safe compartment so that
+use/require work.
=item *
-DOS DJGPP may hang when testing Storable.
+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.
=item *
-st-06compat fails in UNICOS and UNICOS/mk.
+In Search::Dict one can now have a pre-processing hook for the
+lines being searched.
+
+=item *
-This means that you cannot read old (pre-Storable-0.7) Storable images
-made in other platforms.
+The Shell module now has an OO interface.
=item *
-st-store.t and st-retrieve may fail with Compaq C 6.2 on OpenVMS Alpha 7.2.
+The Test module has been significantly enhanced.
-=back
+=item *
-=head2 Threads Are Still Experimental
+The vars pragma now supports declaring fully qualified variables.
+(Something that C<our()> does not and will not support.)
-Multithreading is still an experimental feature. Some platforms
-emit the following message for lib/thr5005
+=item *
- #
- # 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. ;-)
- #
+The C<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.
-and another known thread-related warning is
+=back
- 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
+=head1 Utility Changes
-=head2 The Compiler Suite Is Still Experimental
+=over 4
-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
+Emacs perl mode (emacs/cperl-mode.el) has been updated to version
+4.31.
-(This change was already made in 5.7.0 but bears repeating here.)
+=item *
-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.
+F<emacs/e2ctags.pl> is now much faster.
-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/).
+C<h2ph> now supports C trigraphs.
-=head1 Incompatible Changes
+=item *
-=over 4
+C<h2xs> now produces a template README.
=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">.
+C<h2xs> now uses C<Devel::PPort> for better portability between
+different versions of Perl.
=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.)
+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.
-=back
+=item *
-=head1 Core Enhancements
+C<libnetcfg> has been added to configure the libnet.
-=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.
+C<perlbug> is now much more robust. It also sends the bug report to
+perl.org, not perl.com.
-=head2 PerlIO is Now The Default
+=item *
-=over 4
+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 *
-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:
+C<perlivp> is a new Installation Verification Procedure utility
+for running any time after installing Perl.
- open($fh,'>:crlf :utf8', $path) || ...
+=item *
-or on already opened handles via extended C<binmode>:
+C<pod2html> now allows specifying a cache directory.
- binmode($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).
+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.)
-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.
+C<xsubpp> now understands POD documentation embedded in the *.xs files.
=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" :
+C<xsubpp> now supports OUT keyword.
- open($fh,">:utf8","Uni.txt");
+=back
-Note for EBCDIC users: the pseudo layer ":utf8" is erroneously named
-for you since it's not UTF-8 what you will be getting but instead
-UTF-EBCDIC. See L<perlunicode>, L<utf8>, and
-http://www.unicode.org/unicode/reports/tr16/ for more information.
-In future releases this naming may change.
+=head1 New Documentation
+
+=over 4
=item *
-File handles can translate character encodings from/to Perl's internal
-Unicode form on read/write via the ":encoding()" layer.
+perl56delta details the changes between the 5.005 release and the
+5.6.0 release.
=item *
-File handles can be opened to "in memory" files held in Perl scalars via:
+perlclib documents the internal replacements for standard C library
+functions. (Interesting only for extension writers and Perl core
+hackers.)
- open($fh,'>', \$variable) || ...
+=item *
+
+perldebtut is a Perl debugging tutorial.
=item *
-Anonymous temporary files are available without need to
-'use FileHandle' or other module via
+perlebcdic contains considerations for running Perl on EBCDIC platforms.
- open($fh,"+>", undef) || ...
+=item *
-That is a literal undef, not an undefined value.
+perlintro is a gentle introduction to Perl.
=item *
-The list form of C<open> is now implemented for pipes (at least on UNIX):
+perliol documents the internals of PerlIO with layers.
- open($fh,"-|", 'cat', '/etc/motd')
+=item *
-creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
-the child process.
+perlmodstyle is a style guide for writing modules.
=item *
-The following builtin functions are now overridable: chop(), chomp(),
-each(), keys(), pop(), push(), shift(), splice(), unshift().
+perlnewmod tells about writing and submitting a new module.
=item *
-Formats now support zero-padded decimal fields.
+perlpacktut is a pack() tutorial.
=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.)
+perlpod has been rewritten to be clearer and to record the best
+practices gathered over the years.
=item *
-The printf() and sprintf() now support parameter reordering using the
-C<%\d+\$> and C<*\d+\$> syntaxes. For example
+perlpodspec is a more formal specification of the pod format,
+mainly of interest for writers of pod applications, not to
+people writing in pod.
- print "%2\$s %1\$s\n", "foo", "bar";
+=item *
-will print "bar foo\n"; This feature helps in writing
-internationalised software.
+perlretut is a regular expression tutorial.
=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)
+perlrequick is a regular expressions quick-start guide.
+Yes, much quicker than perlretut.
=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/
+perltodo has been updated.
-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.
+=item *
+
+perltootc has been renamed as perltooc (to not to conflict
+with perltoot in filesystems restricted to "8.3" names)
=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.)
+perluniintro is an introduction to using Unicode in Perl.
+(perlunicode is more of a detailed reference and background
+information)
-=back
+=item *
-=head2 Signals Are Now Safe
+perlutil explains the command line utilities packaged with the Perl
+distribution.
-Perl used to be fragile in that signals arriving at inopportune moments
-could corrupt Perl's internal state.
+=back
-=head1 Modules and Pragmata
+The following platform-specific documents are available before
+the installation as README.I<platform>, and after the installation
+as perlI<platform>:
-=head2 New Modules
+ 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
=over 4
=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.
-
-See L<B::Concise> for more information.
+The documentation for the POSIX-BC platform is called "BS2000", to avoid
+confusion with the Perl POSIX module.
=item *
-Class::ISA, by Sean Burke, for reporting the search path for a
-class's ISA tree, has been added.
+The documentation for the WinCE platform is called "CE", to avoid
+confusion with the perlwin32 documentation on 8.3-restricted filesystems.
-See L<Class::ISA> for more information.
+=back
-=item *
+=head1 Performance Enhancements
-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.
+=over 4
=item *
-Digest, a frontend module for calculating digests (checksums),
-from Gisle Aas, has been added.
-
-See L<Digest> for more information.
+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 *
-Digest::MD5 for calculating MD5 digests (checksums), by Gisle Aas,
-has been added.
+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.
- use Digest::MD5 'md5_hex';
+=item *
- $digest = md5_hex("Thirsty Camel");
+unshift() should now be noticeably faster.
- print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
+=back
+
+=head1 Installation and Configuration Improvements
-NOTE: the MD5 backward compatibility module is deliberately not
-included since its use is discouraged.
+=head2 Generic Improvements
-See L<Digest::MD5> for more information.
+=over 4
=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.
+INSTALL now explains how you can configure Perl to use 64-bit
+integers even on non-64-bit platforms.
-Any encoding supported by Encode module is also available to the
-":encoding()" layer if PerlIO is used.
+=item *
-See L<Encode> for more information.
+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 $prefix changed.) If you do not like this new behaviour,
+specify prefix, siteprefix, and vendorprefix explicitly.
=item *
-Filter::Simple is an easy-to-use frontend to Filter::Util::Call,
-from Damian Conway.
+A new optional location for Perl libraries, otherlibdirs, is available.
+It can be used for example for vendor add-ons without disturbing Perl's
+own library directories.
- # in MyFilter.pm:
+=item *
- package MyFilter;
+In many platforms the vendor-supplied 'cc' is too stripped-down to
+build Perl (basically, 'cc' doesn't do ANSI C). If this seems
+to be the case and 'cc' does not seem to be the GNU C compiler
+'gcc', an automatic attempt is made to find and use 'gcc' instead.
- use Filter::Simple sub {
- while (my ($from, $to) = splice @_, 0, 2) {
- s/$from/$to/g;
- }
- };
+=item *
- 1;
+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.
- # in user's code:
+=item *
- use MyFilter qr/red/ => 'green';
+If binary compatibility with the 5.005 release is not wanted, Configure
+no longer suggests including the 5.005 modules in @INC.
- print "red\n"; # this code is filtered, will print "green\n"
- print "bored\n"; # this code is filtered, will print "bogreen\n"
+=item *
- no MyFilter;
+Configure C<-S> can now run non-interactively.
- print "red\n"; # this code is not filtered, will print "red\n"
+=item *
-See L<Filter::Simple> for more information.
+Configure support for pdp11-style memory models has been removed due
+to obsolescence.
=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.
+configure.gnu now works with options with whitespace in them.
=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;
+installperl now outputs everything to STDERR.
- $country = code2country('jp'); # $country gets 'Japan'
- $code = country2code('Norway'); # $code gets 'no'
+=item *
-See L<Locale::Constants>, L<Locale::Country>, L<Locale::Currency>,
-and L<Locale::Language> for more information.
+$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.)
=item *
-MIME::Base64, by Gisle Aas, allows you to encode data in base64.
+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.
- use MIME::Base64;
+=item *
- $encoded = encode_base64('Aladdin:open sesame');
- $decoded = decode_base64($encoded);
+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.)
- print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
+=item *
-See L<MIME::Base64> for more information.
+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 *
-MIME::QuotedPrint, by Gisle Aas, allows you to encode data in
-quoted-printable encoding.
+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.
- use MIME::QuotedPrint;
+=item *
- $encoded = encode_qp("Smiley in Unicode: \x{263a}");
- $decoded = decode_qp($encoded);
+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.
- print $encoded, "\n"; # "Smiley in Unicode: =263A"
+=item *
-MIME::QuotedPrint has been enhanced to provide the basic methods
-necessary to use it with PerlIO::Via as in :
+Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
+has been documented in INSTALL.
- use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+=item *
-See L<MIME::QuotedPrint> for more information.
+If you have CPAN access (either network or a local copy such as a
+CD-ROM) you can during specify extra modules to Configure to build and
+install with Perl using the -Dextras=... option. See INSTALL for
+more details.
=item *
-PerlIO::Scalar, by Nick Ing-Simmons, provides the implementation of
-IO to "in memory" Perl scalars as discussed above. It also serves as
-an example of a loadable layer. Other future possibilities include
-PerlIO::Array and PerlIO::Code. See L<PerlIO::Scalar> for more
-information.
+In addition to config.over a new override file, config.arch, is
+available. That is supposed to be used by hints file writers for
+architecture-wide changes (as opposed to config.over which is for
+site-wide changes).
=item *
-PerlIO::Via, by Nick Ing-Simmons, acts as a PerlIO layer and wraps
-PerlIO layer functionality provided by a class (typically implemented
-in perl code).
+If your file system supports symbolic links you can build Perl outside
+of the source directory by
- use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+ mkdir /tmp/perl/build/directory
+ cd /tmp/perl/build/directory
+ sh /path/to/perl/source/Configure -Dmksymlinks ...
-This will automatically convert everything output to C<$fh>
-to Quoted-Printable. See L<PerlIO::Via> for more information.
+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
-=item *
+ make all test
-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.
+and Perl will be built and tested, all in /tmp/perl/build/directory.
=item *
-Switch from Damian Conway has been added. Just by saying
-
- use Switch;
-
-you have C<switch> and C<case> available in Perl.
-
- use Switch;
+For Perl developers several new make targets for profiling
+and debugging have been added, see L<perlhack>.
- switch ($val) {
+=over 8
- case 1 { print "number 1" }
- case "a" { print "string a" }
- case [1..10,42] { print "number in list" }
- case (@array) { print "number in list" }
- case /\w+/ { print "pattern" }
- case qr/\w+/ { print "pattern" }
- case (%hash) { print "entry in hash" }
- case (\%hash) { print "entry in hash" }
- case (\&sub) { print "arg to subroutine" }
- else { print "previous case not true" }
- }
+=item *
-See L<Switch> for more information.
+Use of the F<gprof> tool to profile Perl has been documented in
+L<perlhack>. There is a make target called "perl.gprof" for
+generating a gprofiled Perl executable.
=item *
-Text::Balanced from Damian Conway has been added, for
-extracting delimited text sequences from strings.
-
- use Text::Balanced 'extract_delimited';
+If you have GCC 3, there is a make target called "perl.gcov" for
+creating a gcoved Perl executable for coverage analysis. See
+L<perlhack>.
- ($a, $b) = extract_delimited("'never say never', he never said", "'", '');
+=item *
-$a will be "'never say never'", $b will be ', he never said'.
+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.
-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.
+=back
=item *
-Tie::RefHash::Nestable, by Edward Avis, allows storing hash references
-(unlike the standard Tie::RefHash) The module is contained within
-Tie::RefHash.
+Guidelines of how to construct minimal Perl installations have
+been added to INSTALL.
=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.
+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>).
+
+But note that the Thread.pm interface is now shared by both
+thread models.
=back
-=head2 Updated And Improved Modules and Pragmata
+=head2 New Or Improved Platforms
+
+For the list of platforms known to support Perl,
+see L<perlport/"Supported Platforms">.
=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.
+AIX dynamic loading should be now better supported.
=item *
-Class::Struct can now define the classes in compile time.
+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 *
-Math::BigFloat has undergone much fixing, and in addition the fmod()
-function now supports modulus operations.
+After a long pause, AmigaOS has been verified to be happy with Perl.
+
+=item *
-(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/)
+AtheOS (http://www.atheos.cx/) is a new platform.
=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).
+BeOS has been reclaimed.
=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.
+DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
=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.
+DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
=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.
+EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
+have been regained. Many test suite tests still fail and the
+co-existence of Unicode and EBCDIC isn't quite settled, but the
+situation is much better than with Perl 5.6. See L<perlos390>,
+L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
=item *
-The C<open> pragma allows layers other than ":raw" and ":crlf" when
-using PerlIO.
+Building perl with -Duseithreads or -Duse5005threads now works under
+HP-UX 10.20 (previously it only worked under 10.30 or later). You will
+need a thread library package installed. See README.hpux.
=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.
+MacOS Classic (MacPerl has of course been available since
+perl 5.004 but now the source code bases of standard Perl
+and MacPerl have been synchronised)
=item *
-The Test module has been significantly enhanced. Its use is
-greatly recommended for module writers.
+MacOS X (or Darwin) should now be able to build Perl even on HFS+
+filesystems. (The case-insensitivity confused the Perl build process.)
=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.
+NCR MP-RAS is now supported.
-=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.
+All the NetBSD specific patches (except for the installation
+specific ones) have been merged back to the main distribution.
-=head1 Performance Enhancements
+=item *
-=over 4
+NetWare from Novell is now supported. See L<perlnetware>.
=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.
+NonStop-UX is now supported.
=item *
-unshift() should now be noticeably faster.
+NEC SUPER-UX is now supported.
-=back
+=item *
-=head1 Utility Changes
+All the OpenBSD specific patches (except for the installation
+specific ones) have been merged back to the main distribution.
-=over 4
+=item *
+
+Perl has been tested with the GNU pth userlevel thread package
+( http://www.gnu.org/software/pth/pth.html ) . All but one thread
+test worked, and that one failure was because of test results arriving
+in unexpected order.
=item *
-h2xs now produces template README.
+Amdahl UTS UNIX mainframe platform is now supported.
=item *
-s2p has been completely rewritten in Perl. (It is in fact a full
-implementation of sed in Perl.)
+WinCE is now supported. See L<perlce>.
=item *
-xsubpp now supports OUT keyword.
+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
-=head1 New Documentation
+=head1 Selected Bug Fixes
-=head2 perlclib
+Numerous memory leaks and uninitialized memory accesses have been
+hunted down. Most importantly anonymous subs used to leak quite
+a bit.
-Internal replacements for standard C library functions.
-(Interesting only for extension writers and Perl core hackers.)
+=over 4
-=head2 perliol
+=item *
-Internals of PerlIO with layers.
+The autouse pragma didn't work for Multi::Part::Function::Names.
-=head2 README.aix
+=item *
-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>.
+caller() could cause core dumps in certain situations. Carp was sometimes
+affected by this problem.
-=head2 README.bs2000
+=item *
-Documentation on compiling Perl on the POSIX-BC platform (an EBCDIC
-mainframe environment) has been added.
+chop(@list) in list context returned the characters chopped in
+reverse order. This has been reversed to be in the right order.
-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>.
+=item *
-=head2 README.macos
+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.
-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>.
+=item *
-=head2 README.mpeix
+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.
-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
+The order of DESTROYs has been made more predictable.
-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
+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.
-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>.
+=item *
-=head2 Porting/repository.pod
+Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
+when statically building extensions into perl. This has been corrected.
-Documentation on how to use the Perl source repository has been added.
+=item *
-=head1 Installation and Configuration Improvements
+L<dprofpp> -R didn't work.
-=over 4
+=item *
+C<*foo{FORMAT}> now works.
=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.
+Infinity is now recognized as a number.
=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.)
+UNIVERSAL::isa no longer caches methods incorrectly. (This broke
+the Tk extension with 5.6.0.)
=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.
+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 *
-Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM
-has been documented in INSTALL.
+Lexicals II: lexicals leaked at file scope into subroutines that
+were declared before the lexicals.
=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.
-
-=back
-
-=head2 New Or Improved Platforms
-
-For the list of platforms known to support Perl,
-see L<perlport/"Supported Platforms">.
-
-=over 4
+Lexical warnings now propagating correctly between scopes
+and into C<eval "...">.
=item *
-AIX dynamic loading should be now better supported.
+C<use warnings qw(FATAL all)> did not work as intended. This has been
+corrected.
=item *
-After a long pause, AmigaOS has been verified to be happy with Perl.
+warnings::enabled() now reports the state of $^W correctly if the caller
+isn't using lexical warnings.
=item *
-EBCDIC platforms (z/OS, also known as OS/390, POSIX-BC, and VM/ESA)
-have been regained. Many test suite tests still fail and the
-co-existence of Unicode and EBCDIC isn't quite settled, but the
-situation is much better than with Perl 5.6. See L<perlos390>,
-L<perlbs2000> (for POSIX-BC), and L<perlvmesa> for more information.
+Line renumbering with eval and C<#line> now works.
=item *
-Building perl with -Duseithreads or -Duse5005threads now works under
-HP-UX 10.20 (previously it only worked under 10.30 or later). You will
-need a thread library package installed. See README.hpux.
+Fixed numerous memory leaks, especially in eval "".
=item *
-MacOS Classic (MacPerl has of course been available since
-perl 5.004 but now the source code bases of standard Perl
-and MacPerl have been synchronised)
+mkdir() now ignores trailing slashes in the directory name,
+as mandated by POSIX.
=item *
-NCR MP-RAS is now supported.
+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 *
-NonStop-UX is now supported.
+Modulus of unsigned numbers now works (4063328477 % 65535 used to
+return 27406, instead of 27047).
=item *
-Amdahl UTS is now supported.
+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 *
-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
-
-=head2 Generic Improvements
-
-=over 4
+Numeric conversions did not recognize changes in the string value
+properly in certain circumstances.
=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.
+Attributes (like :shared) didn't work with our().
=item *
-Some new Configure symbols, useful for extension writers:
-
-=over 8
-
-=item d_cmsghdr
-
-For struct cmsghdr.
-
-=item d_fcntl_can_lock
-
-Whether fcntl() can be used for file locking.
-
-=item d_fsync
-
-=item d_getitimer
-
-=item d_getpagsz
-
-For getpagesize(), though you should prefer POSIX::sysconf(_SC_PAGE_SIZE))
-
-=item d_msghdr_s
-
-For struct msghdr.
-
-=item need_va_copy
-
-Whether one needs to use Perl_va_copy() to copy varargs.
-
-=item d_readv
-
-=item d_recvmsg
-
-=item d_sendmsg
-
-=item sig_size
-
-The number of elements in an array needed to hold all the available signals.
-
-=item d_sockatmark
-
-=item d_strtoq
-
-=item d_u32align
-
-Whether one needs to access character data aligned by U32 sized pointers.
-
-=item d_ualarm
-
-=item d_usleep
-
-=back
+our() variables will not cause "will not stay shared" warnings.
=item *
-Removed Configure symbols: the PDP-11 memory model settings: huge,
-large, medium, models.
+"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 *
-SOCKS support is now much more robust.
+pack "Z" now correctly terminates the string with "\0".
=item *
-If your file system supports symbolic links you can build Perl outside
-of the source directory by
-
- mkdir /tmp/perl/build/directory
- cd /tmp/perl/build/directory
- sh /path/to/perl/source/Configure -Dmksymlinks ...
-
-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
-
- make all test
-
-and Perl will be built and tested, all in /tmp/perl/build/directory.
-
-=back
-
-=head1 Selected Bug Fixes
-
-Numerous memory leaks and uninitialized memory accesses have been hunted down.
-Most importantly anonymous subs used to leak quite a bit.
-
-=over 4
+Fix password routines which in some shadow password platforms
+(e.g. HP-UX) caused getpwent() to return every other entry.
=item *
-chop(@list) in list context returned the characters chopped in
-reverse order. This has been reversed to be in the right order.
+The PERL5OPT environment variable (for passing command line arguments
+to Perl) didn't work for more than a single group of options.
=item *
-The order of DESTROYs has been made more predictable.
+PERL5OPT with embedded spaces didn't work.
=item *
-mkdir() now ignores trailing slashes in the directory name,
-as mandated by POSIX.
+printf() no longer resets the numeric locale to "C".
=item *
-Attributes (like :shared) didn't work with our().
+C<qw(a\\b)> now parses correctly as C<'a\\b'>.
=item *
-The PERL5OPT environment variable (for passing command line arguments
-to Perl) didn't work for more than a single group of options.
+pos() did not return the correct value within s///ge in earlier
+versions. This is now handled correctly.
=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.
+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 *
-All but the first argument of the IO syswrite() method are now optional.
+Regular expressions on references and overloaded scalars now work.
=item *
-Tie::ARRAY SPLICE method was broken.
+Right-hand side magic (GMAGIC) could in many cases such as string
+concatenation be invoked too many times.
=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
+scalar() now forces scalar context even when used in void context.
=item *
-Linux previously had problems related to sockaddrlen when using
-accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
+SOCKS support is now much more robust.
=item *
-Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
+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.
=item *
-Windows
-
-=over 8
+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).
=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 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.
=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.
+Some cases of inconsistent taint propagation (such as within hash
+values) have been fixed.
=item *
-Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
+The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
+of simple pattern matches. These are now handled better.
=item *
-HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
+Regular expression debug output (whether through C<use re 'debug'>
+or via C<-Dr>) now looks better.
=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
+Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
+bug has been fixed.
=item *
-If an attempt to use a (non-blessed) reference as an array index
-is made, a warning is given.
+Use of $& could trigger a core dump under some situations. This
+is now avoided.
=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
+The regular expression captured submatches ($1, $2, ...) are now
+more consistently unset if the match fails, instead of leaving false
+data lying around in them.
=item *
-Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv().
-For the full list of the available APIs see L<perlapi>.
+readline() on files opened in "slurp" mode could return an extra "" at
+the end in certain situations. This has been corrected.
=item *
-dTHR and djSP have been obsoleted; the former removed (because it's
-a no-op) and the latter replaced with dSP.
+Autovivification of symbolic references of special variables described
+in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
+again now.
=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
-
-=head1 New Tests
-
-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.
-
-=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 vac 5.0.0.0 May Produce Buggy Code For Perl
-
-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.
-
-=head2 lib/ftmp-security tests warn 'system possibly insecure'
-
-Don't panic. Read INSTALL 'make test' section instead.
-
-=head2 lib/io_multihomed Fails In LP64-Configured HP-UX
-
-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).
-
-=head2 Test lib/posix Subtest 9 Fails In LP64-Configured HP-UX
-
-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.
-
-=head2 lib/b test 19
-
-The test fails on various platforms (PA64 and IA64 are known), but the
-exact cause is still being investigated.
-
-=head2 Linux With Sfio Fails op/misc Test 48
-
-No known fix.
-
-=head2 sigaction test 13 in VMS
-
-The test is known to fail; whether it's because of VMS of because
-of faulty test is not known.
-
-=head2 sprintf tests 129 and 130
-
-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".)
-
-=head2 Failure of Thread tests
-
-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.)
-
-=head2 Localising a Tied Variable Leaks Memory
-
- use Tie::Hash;
- tie my %tie_hash => 'Tie::StdHash';
-
- ...
-
- local($tie_hash{Foo}) = 1; # leaks
-
-Code like the above is known to leak memory every time the local()
-is executed.
-
-=head2 Self-tying of Arrays and Hashes Is Forbidden
-
-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).
-
-=head2 Building Extensions Can Fail Because Of Largefiles
+Sys::Syslog ignored the C<LOG_AUTH> constant.
-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.
-
-=head2 The Compiler Suite Is Still Experimental
-
-The compiler suite is slowly getting better but is nowhere near
-working order yet.
-
-=head1 Security Vulnerability Closed
-
-(This change was already made in 5.7.0 but bears repeating here.)
-
-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.
-
-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.
-
-See http://www.cpan.org/src/5.0/sperl-2000-08-05/sperl-2000-08-05.txt
-for more information.
-
-=head1 Incompatible Changes
-
-=head2 64-bit platforms and malloc
-
-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.
-
-=head2 AIX Dynaloading
-
-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.
-
-=head2 Socket Extension Dynamic in VMS
-
-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.
-
-=head2 Different Definition of the Unicode Character Classes \p{In...}
-
-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 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.
-
-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>).
-
-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>.
-
-=head2 Deprecations
-
-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.
-
-The syntaxes C<@a->[...]> and C<@h->{...}> have now been deprecated.
-
-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.
+=item *
-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.
+All but the first argument of the IO syswrite() method are now optional.
-The chdir(undef) and chdir('') behaviors to match chdir() has been
-deprecated. In future versions, chdir(undef) and chdir('') will
-simply fail.
+=item *
-=head1 Core Enhancements
+$AUTOLOAD, sort(), lock(), and spawning subprocesses
+in multiple threads simultaneously are now thread-safe.
-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.
+=item *
-=over 4
+Tie::ARRAY SPLICE method was broken.
=item *
-The rules for allowing underscores (underbars) in numeric constants
-have been relaxed and simplified: now you can have an underscore
-B<between digits>.
+Allow read-only string on left hand side of non-modifying tr///.
=item *
-GMAGIC (right-hand side magic) could in many cases such as string
-concatenation be invoked too many times.
+Several Unicode fixes.
+
+=over 8
=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.
+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.
=item *
-Lexicals II: lexicals leaked at file scope into subroutines that
-were declared before the lexicals.
+The character tables have been updated to Unicode 3.1.1.
=item *
-Lvalue subroutines can now return C<undef> in list context.
+Comparing with utf8 data does not magically upgrade non-utf8 data
+into utf8. (This was a problem for example if you were mixing data
+from I/O and Unicode data: your output might have got magically encoded
+as UTF-8.)
=item *
-The C<op_clear> and C<op_null> are now exported.
+Generating illegal Unicode code points like U+FFFE, or the UTF-16
+surrogates, now also generates an optional warning.
=item *
-A new special regular expression variable has been introduced:
-C<$^N>, which contains the most-recently closed group (submatch).
+C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
=item *
-L<utime> now supports C<utime undef, undef, @files> to change the
-file timestamps to the current time.
+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.
=item *
-The Perl parser has been stress tested using both random input and
-Markov chain input.
+The C<tr///> operator now works. Note that the C<tr///CU>
+functionality has been removed (but see pack('U0', ...)).
=item *
=item *
-VMS now works under PerlIO.
+Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
+This has been corrected.
=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>.
+Zero entries were missing from the Unicode classes like C<IsDigit>.
=back
-=head1 Modules and Pragmata
-
-=head2 New Modules and Distributions
-
-=over 4
-
-=item *
-
-L<Attribute::Handlers> - Simpler definition of attribute handlers
-
=item *
-L<ExtUtils::Constant> - generate XS code to import C header constants
+Large unsigned numbers (those above 2**31) could sometimes lose their
+unsignedness, causing bogus results in arithmetic operations.
-=item *
-
-L<I18N::Langinfo> - query locale information
+=back
-=item *
+=head2 Platform Specific Changes and Fixes
-L<I18N::LangTags> - functions for dealing with RFC3066-style language tags
+=over 4
=item *
-L<libnet> - a collection of perl5 modules related to network programming
+BSDI 4.*
-Perl installation leaves libnet unconfigured, use F<libnetcfg> to configure.
+Perl now works on post-4.0 BSD/OSes.
=item *
-L<List::Util> - selection of general-utility list subroutines
-
-=item *
+All BSDs
-L<Locale::Maketext> - framework for localization
+Setting C<$0> now works (as much as possible; see L<perlvar> for details).
=item *
-L<Memoize> - Make your functions faster by trading space for time
+Cygwin
+
+Numerous updates; currently synchronised with Cygwin 1.1.4.
=item *
-L<NEXT> - pseudo-class for method redispatch
+Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
=item *
-L<Scalar::Util> - selection of general-utility scalar subroutines
+EPOC
+
+EPOC update after Perl 5.6.0. See README.epoc.
=item *
-L<Test::More> - yet another framework for writing test scripts
+FreeBSD 3.*
+
+Perl now works on post-3.0 FreeBSDs.
=item *
-L<Test::Simple> - Basic utilities for writing tests
+HP-UX
+
+README.hpux updated; C<Configure -Duse64bitall> now almost works.
=item *
-L<Time::HiRes> - high resolution ualarm, usleep, and gettimeofday
+IRIX
+
+Numerous compilation flag and hint enhancements; accidental mixing
+of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
=item *
-L<Time::Piece> - Object Oriented time objects
+Linux
-(Previously known as L<Time::Object>.)
+=over 8
=item *
-L<Time::Seconds> - a simple API to convert seconds to other date values
+Long doubles should now work (see INSTALL).
=item *
-L<UnicodeCD> - Unicode Character Database
+Linux previously had problems related to sockaddrlen when using
+accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
=back
-=head2 Updated And Improved Modules and Pragmata
+=item *
-=over 4
+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<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.
+MPE/iX
+
+MPE/iX update after Perl 5.6.0. See README.mpeix.
=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.
+NetBSD/sparc
+
+Perl now works on NetBSD/sparc.
=item *
-L<Cwd> extension is now (even) faster.
+OS/2
+
+Now works with usethreads (see INSTALL).
=item *
-L<DB_File> extension has been updated to version 1.77.
+Solaris
+
+64-bitness using the Sun Workshop compiler now works.
=item *
-L<Fcntl>, L<Socket>, and L<Sys::Syslog> have been rewritten to use the
-new-style constant dispatch section (see L<ExtUtils::Constant>).
+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<File::Find> is now (again) reentrant. It also has been made
-more portable.
+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<File::Glob> now supports C<GLOB_LIMIT> constant to limit the
-size of the returned list of filenames.
+VMS
-=item *
+chdir() now works better despite a CRT bug; now works with MULTIPLICITY
+(see INSTALL); now works with Perl's malloc.
-L<IO::Socket::INET> now supports C<LocalPort> of zero (usually meaning
-that the operating system will make one up.)
+The tainting of C<%ENV> elements via C<keys> or C<values> was previously
+unimplemented. It now works as documented.
-=item *
+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.
-The L<vars> pragma now supports declaring fully qualified variables.
-(Something that C<our()> does not and will not support.)
+POSIX-style signals are now emulated much better on VMS versions prior
+to 7.0.
-=back
+The C<system> function and backticks operator have improved
+functionality and better error handling.
-=head1 Utility Changes
+=item *
-=over 4
+Windows
+
+=over 8
=item *
-The F<emacs/e2ctags.pl> is now much faster.
+accept() no longer leaks memory.
=item *
-L<h2ph> now supports C trigraphs.
+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<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.
+Better chdir() return value for a non-existent directory.
=item *
-L<libnetcfg> has been added to configure the libnet.
+Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
=item *
-The F<Pod::Html> (and thusly L<pod2html>) now allows specifying
-a cache directory.
+New %ENV entries now propagate to subprocesses.
-=back
+=item *
-=head1 New Documentation
+Current directory entries in %ENV are now correctly propagated to child
+processes.
-=over 4
+=item *
+
+$ENV{LIB} now used to search for libs under Visual C.
=item *
-L<Locale::Maketext::TPJ13> is an article about software localization,
-originally published in The Perl Journal #13, republished here with
-kind permission.
+fork() emulation has been improved in various ways, but still continues
+to be experimental. See L<perlfork> for known bugs and caveats.
=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>.
+A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
=item *
-The F<Todo> and F<Todo-5.6> files have been merged into L<perltodo>.
+Win32::GetCwd() correctly returns C:\ instead of C: when at the drive root.
+Other bugs in chdir() and Cwd::cwd() have also been fixed.
=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.
+HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
-=back
+=item *
-=head1 Installation and Configuration Improvements
+The makefiles now provide a single switch to bulk-enable all the features
+enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
-=head2 New Or Improved Platforms
+=item *
-=over 4
+Allow REG_EXPAND_SZ keys in the registry.
=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>.
+Can now send() from all threads, not just the first one.
=item *
-AtheOS (http://www.atheos.cx/) is a new platform.
+Fake signal handling reenabled, bugs and all.
=item *
-DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
+%SIG has been enabled under USE_ITHREADS, but its use is completely
+unsupported under all configurations.
=item *
-DYNIX/ptx platform (a.k.a. dynixptx) is supported at or near osvers 4.5.2.
+Less stack reserved per thread so that more threads can run
+concurrently. (Still 16M per thread.)
=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>.
+C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
+(works better when perl is running as service).
=item *
-MacOS X (or Darwin) should now be able to build Perl even on HFS+
-filesystems. (The case-insensitivity confused the Perl build process.)
+Better UNC path handling under ithreads.
=item *
-NetWare from Novell is now supported. See L<perlnetware>.
+wait(), waitpid() and backticks now return the correct exit status under
+Windows 9x.
=item *
-The Amdahl UTS UNIX mainframe platform is now supported.
+winsock handle leak fixed.
=back
-=head2 Generic Improvements
+=back
+
+=head1 New or Changed Diagnostics
=over 4
=item *
-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>.
+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 *
-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.
+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 *
-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 "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 *
-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
+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 *
-The autouse pragma didn't work for Multi::Part::Function::Names.
+If an attempt to use a (non-blessed) reference as an array index
+is made, a warning is given.
=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.
+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 *
-L<dprofpp> -R didn't work.
+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 *
-PERL5OPT with embedded spaces didn't work.
+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.
=item *
-L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
+Using arrays or hashes as references (e.g. C<< %foo->{bar} >>
+has been deprecated for a while. Now you will get an optional warning.
=back
-=head2 Platform Specific Changes and Fixes
+=head1 Changed Internals
=over 4
=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
+perlapi.pod (a companion to perlguts) now attempts to document the
+internal API.
-=head1 New or Changed Diagnostics
+=item *
-=over 4
+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 *
-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.
+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 *
-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.
+Made possible to propagate customised exceptions via croak()ing.
=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.
+Now xsubs can have attributes just like subs. (Well, at least the
+built-in attributes.)
=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.
+dTHR and djSP have been obsoleted; the former removed (because it's
+a no-op) and the latter replaced with dSP.
-=back
+=item *
-=head1 Source Code Enhancements
+PERL_OBJECT has been completely removed.
-=head2 MAGIC constants
+=item *
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.
-
-=head2 Regex pre-/post-compilation items matched up
+=item *
The regex compiler now maintains a structure that identifies nodes in
the compiled bytecode with the corresponding syntactic features of the
C<offsets> member of the C<struct regexp>. See L<perldebguts> for more
complete information.
-=head2 gcc -Wall
+=item *
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.
+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 *
+
+F<perly.c>, F<sv.c>, and F<sv.h> have now been extensively commented.
+
+=item *
+
+Documentation on how to use the Perl source repository has been added
+to F<Porting/repository.pod>.
+
+=item *
+
+There are now several profiling make targets.
+
+=back
+
+=head1 Security Vulnerability Closed
+
+(This change was already made in 5.7.0 but bears repeating here.)
+
+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.
+
+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 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
+
+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.
+
=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