-M=head1 NAME
+=head1 NAME
perldelta - what is new for perl v5.8.0
=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.
+
+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.
+
+If you are upgrading from Perl 5.005_03, you might also want
+to read L<perl56delta>.
+
+=head1 Highlights In 5.8.0
+
+=over 4
+
+=item *
+
+Better Unicode support
+
+=item *
+
+New Thread Implementation
+
+=item *
+
+Many New Modules
+
+=item *
+
+Better Numeric Accuracy
+
+=item *
+
+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 more being
-used because it simply does not work with 8-byte pointers. Also,
+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. Such platforms
-include 64-bit Alpha, MIPS, HPPA, PPC, and Sparc.
+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
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
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 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
Markov chain input and the few found crashes and lockups have been
fixed.
-=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.
+=head2 REF(...) Instead Of SCALAR(...)
-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.
+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().
-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.
+=head2 Deprecations
=over 4
=item *
-A reference to a reference now stringify as "REF(0x81485ec)" instead
-of "SCALAR(0x81485ec)" in order to be more consistent with the return
-value of ref().
+The obsolete chat2 library that should never have been allowed
+to escape the laboratory has been decommissioned.
+
+=item *
+
+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 *
=item *
-The obsolete chat2 library that should never have been allowed
-to escape the laboratory has been decommissioned.
+The (bogus) escape sequences \8 and \9 now give an optional warning
+("Unrecognized escape passed through"). There is no need to \-escape
+any C<\w> character.
+
+=item *
+
+The 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 *
+
+Spurious syntax errors generated in certain situations, when glob()
+caused File::Glob to be loaded for the first time, have been fixed.
+
+=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">.
+
+=item *
+
+lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
+In future releases this may become a fatal error.
+
+=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.
=item *
=item *
-The (bogus) escape sequences \8 and \9 now give an optional warning
-("Unrecognized escape passed through"). There is no need to \-escape
-any C<\w> character.
+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 *
-lstat(FILEHANDLE) now gives a warning because the operation makes no sense.
-In future releases this may become a fatal error.
+The syntaxes C<< @a->[...] >> and C<< %h->{...} >> have now been deprecated.
=item *
-The long deprecated uppercase aliases for the string comparison
-operators (EQ, NE, LT, LE, GE, GT) have now been removed.
+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 *
-The regular expression captured submatches ($1, $2, ...) are now
-more consistently unset if the match fails, instead of leaving false
-data lying around in them.
+The long deprecated uppercase aliases for the string comparison
+operators (EQ, NE, LT, LE, GE, GT) have now been removed.
=item *
=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">.
-
-=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.)
+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 Core Enhancements
-=head2 AUTOLOAD Is Now Lvaluable
-
-AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
-to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value.
-
=head2 PerlIO is Now The Default
=over 4
creates a pipe, and runs the equivalent of exec('cat', '/etc/motd') in
the child process.
-=item *
-
-The following builtin functions are now overridable: chop(), chomp(),
-each(), keys(), pop(), push(), shift(), splice(), unshift().
-
-=item *
-
-Formats now support zero-padded decimal fields.
+=back
-=item *
+=head2 Safe Signals
-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.)
+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).
-=item *
+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.
-The printf() and sprintf() now support parameter reordering using the
-C<%\d+\$> and C<*\d+\$> syntaxes. For example
+=head2 Unicode Overhaul
- print "%2\$s %1\$s\n", "foo", "bar";
+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.
-will print "bar foo\n"; This feature helps in writing
-internationalised software.
+=over 4
=item *
-Unicode in general should be now much more usable. Unicode can be
-used in hash keys, Unicode in regular expressions should work now,
-Unicode in tr/// should work now (though tr/// seems to be a
-particularly tricky to get right, so you have been warned)
+The Unicode Character Database coming with Perl has been upgraded
+to Unicode 3.1.1. For more information, see http://www.unicode.org/.
=item *
-The Unicode Character Database coming with Perl has been upgraded
-to Unicode 3.1. For more information, see http://www.unicode.org/,
-and http://www.unicode.org/unicode/reports/tr27/
-
For developers interested in enhancing Perl's Unicode capabilities:
almost all the UCD files are included with the Perl distribution in
-the lib/unicode subdirectory. The most notable omission, for space
+the F<lib/unicore subdirectory>. The most notable omission, for space
considerations, is the Unihan database.
=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.)
-
-=back
+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.)
-=head2 Signals Are Now Safe
+See "New Unicode Properties" earlier in this document for additional
+information on changes with Unicode properties.
-Perl used to be fragile in that signals arriving at inopportune moments
-could corrupt Perl's internal state.
+=back
=head2 Understanding of Numbers
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 *
+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 *
+
C<perl -d:Module=arg,arg,arg> now works (previously one couldn't pass
in multiple arguments.)
=item *
+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 *
+
+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 *
+
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
=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.
+Formats now support zero-padded decimal fields.
=item *
-Lexicals II: lexicals leaked at file scope into subroutines that
-were declared before the lexicals.
+Lvalue subroutines can now return C<undef> in list context.
+However, the lvalue subroutine feature still remains experimental.
=item *
-Lvalue subroutines can now return C<undef> in list context.
+A lost warning "Can't declare ... dereference in my" has been
+restored (Perl had it earlier but it became lost in later releases.)
=item *
=item *
+The following builtin functions are now overridable: each(), keys(),
+pop(), push(), shift(), splice(), unshift().
+
+=item *
+
C<pack('U0a*', ...)> can now be used to force a string to UTF8.
=item *
=item *
+The printf() and sprintf() now support parameter reordering using the
+C<%\d+\$> and C<*\d+\$> syntaxes. For example
+
+ print "%2\$s %1\$s\n", "foo", "bar";
+
+will print "bar foo\n". This feature helps in writing
+internationalised software, and in general when the order
+of the parameters can vary.
+
+=item *
+
prototype(\&) is now available.
=item *
-Right-hand side magic (GMAGIC) could in many cases such as string
-concatenation be invoked too many times.
+prototype(\[$@%&]) is now available to implicitly create references
+(useful for example if you want to emulate the tie() interface).
=item *
-The rules for allowing underscores (underbars) in numeric constants
-have been relaxed and simplified: now you can have an underscore
-simply B<between digits>.
+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 *
+
+If tr/// is just counting characters, it doesn't attempt to
+modify its target.
=item *
-An UNTIE method is now available.
+untie() will now call an UNTIE() hook if it exists. See L<perltie>
+for details.
=item *
=item *
-C<eval "v200"> now works.
+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 Modules and Pragmata
-=head2 New Modules
+=head2 New Modules and Pragmata
=over 4
# later, in some package using or inheriting from MyPack...
my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called
-
+
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 *
+C<Devel::PPPort>, originally from Kenneth Albanowski and now
+maintained by Paul Marquess, has been added. It is primarily used
+by C<h2xs> to enhance portability of of XS modules between different
+versions of Perl.
+
+=item *
+
C<Digest>, frontend module for calculating digests (checksums), from
Gisle Aas, has been added. See L<Digest>.
print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
NOTE: the C<MD5> backward compatibility module is deliberately not
-included since its use is discouraged.
+included since its further use is discouraged.
=item *
=item *
C<I18N::LangTags> has functions for dealing with RFC3066-style
-language tags, by Sean Burke. See <I18N::LangTags>.
+language tags, by Sean Burke. See L<I18N::LangTags>.
=item *
=item *
C<List::Util> is a selection of general-utility list subroutines, like
-sum(), min(), first(), and shuffle(), by Graham barr. See L<List::Util>.
+sum(), min(), first(), and shuffle(), by Graham Barr. See L<List::Util>.
=item *
necessary to use it with PerlIO::Via as in :
use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+ open($fh,">Via(MIME::QuotedPrint)",$path);
See L<MIME::QuotedPrint>.
=item *
+C<open> is a new pragma for setting the default I/O disciplines
+for open().
+
+=item *
+
C<PerlIO::Scalar> provides the implementation of IO to "in memory"
Perl scalars as discussed above, from Nick Ing-Simmons. It also
serves as an example of a loadable PerlIO layer. Other future
code), from Nick Ing-Simmons.
use MIME::QuotedPrint;
- open($fh,">Via(MIME::QuotedPrint)",$path)
+ open($fh,">Via(MIME::QuotedPrint)",$path);
This will automatically convert everything output to C<$fh>
to Quoted-Printable. See L<PerlIO::Via>.
=item *
+C<Pod::ParseLink>, by Russ Allbery, has been added,
+to parse LZ<><> links in pods as described in the new
+perlpodspec.
+
+=item *
+
C<Pod::Text::Overstrike>, by Joe Smith, has been added.
It converts POD data to formatted overstrike text.
See L<Pod::Text::Overstrike>.
=item *
+C<sort> is a new pragma for controlling the behaviour of sort().
+
+=item *
+
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 *
-C<Test::Simple> has the- basic utilities for writing tests, by Michael
+C<Test::Simple> has basic utilities for writing tests, by Michael
Schwern. See L<Test::Simple>.
=item *
=item *
-C<threads> is an interface interpreter threads, by Arthur Bergman.
+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 then available only as an internal interface for
-extension writers. See L<threads>.
+Perl 5.6 but only available as an internal interface for extension
+writers (and for Win32 Perl for C<fork()> emulation). See L<threads>.
=item *
=item *
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).
+references (unlike the standard Tie::RefHash) The module is contained
+within Tie::RefHash, see L<Tie::RefHash>.
=item *
=item *
-AutoLoader can now be disabled with C<no AutoLoader;>,
+AutoLoader can now be disabled with C<no AutoLoader;>.
+
+=item *
+
+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 *
+
+Class::Struct can now define the classes in compile time.
+
+=item *
+
+Class::Struct now assigns the array/hash element if the accessor
+is called with an array/hash element as the B<sole> argument.
=item *
=item *
+Data::Dumper has now an option to dump code references
+using B::Deparse.
+
+=item *
+
+DB_File now supports newer Berkeley DB versions, among
+other improvements.
+
+=item *
+
The English module can now be used without the infamous performance
hit by saying
=item *
+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 *
+
+File::Find now chdir()s correctly when chasing symbolic links.
+
+=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.
=item *
+File::Find is now (again) reentrant. It also has been made
+more portable.
+
+=item *
+
File::Glob::glob() renamed to File::Glob::bsd_glob() to avoid
prototype mismatch with CORE::glob().
=item *
-IPC::Open3 now allows the use of numeric file descriptors.
+File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
+the returned list of filenames.
=item *
-use lib now works identically to @INC. Removing directories
-with 'no lib' now works.
+Devel::Peek now has an interface for the Perl memory statistics
+(this works only if you are using perl's malloc, and if you have
+compiled with debugging).
=item *
-C<%INC> now localised in a Safe compartment so that use/require work.
+IPC::Open3 now allows the use of numeric file descriptors.
=item *
-The Shell module now has an OO interface.
-
-=item *
-
-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 *
-
-Class::Struct can now define the classes in compile time.
+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.
=item *
-Class::Struct now assigns the array/hash element if the accessor
-is called with an array/hash element as the B<sole> argument.
+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 *
-Fcntl, Socket, and Sys::Syslog have been rewritten to use the
-new-style constant dispatch section (see L<ExtUtils::Constant>).
+IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
+that the operating system will make one up.)
=item *
-File::Find is now (again) reentrant. It also has been made
-more portable.
+use lib now works identically to @INC. Removing directories
+with 'no lib' now works.
=item *
-File::Glob now supports C<GLOB_LIMIT> constant to limit the size of
-the returned list of filenames.
+ExtUtils::MakeMaker now uses File::Spec internally, which hopefully
+leads into better portability.
=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).
+Math::BigFloat and Math::BigInt have undergone a full rewrite.
+They are now magnitudes faster, and they support various
+bignum libraries such as GMP and PARI as their backends.
=item *
-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.
+Math::Complex handles inf, NaN etc., better.
=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.
+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 *
-IO::Socket::INET now supports C<LocalPort> of zero (usually meaning
-that the operating system will make one up.)
+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 *
-Math::BigFloat and Math::BigInt have undergone much fixing,
-they are now magnitudes faster, and they support various
-bignum libraries such as GMP and PARI as their backends.
+In Safe the C<%INC> now localised in a Safe compartment so that
+use/require work.
=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.
+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 *
-The C<open> pragma allows layers other than ":raw" and ":crlf" when
-using PerlIO.
+In Search::Dict one can now have a pre-processing hook for the
+lines being searched.
=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.
+The Shell module now has an OO interface.
=item *
=item *
-The C<vars> pragma now supports declaring fully qualified variables.
+The vars pragma now supports declaring fully qualified variables.
(Something that C<our()> does not and will not support.)
=item *
-The utf8:: name space (as in the pragma) provides various
+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.
=item *
-h2xs now produces a template README.
+C<h2ph> now supports C trigraphs.
+
+=item *
+
+C<h2xs> now produces a template README.
=item *
-L<h2ph> now supports C trigraphs.
+C<h2xs> now uses C<Devel::PPort> for better portability between
+different versions of Perl.
=item *
-L<h2xs> uses the new L<ExtUtils::Constant> module which will affect
+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),
=item *
-L<libnetcfg> has been added to configure the libnet.
+C<libnetcfg> has been added to configure the libnet.
=item *
-perlbug is now much more robust. It also sends the bug report to
+C<perlbug> is now much more robust. It also sends the bug report to
perl.org, not perl.com.
=item *
-perlcc has been rewritten and its user interface (that is,
+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 *
-perlivp is a new utility for doing Installation Verification
-Procedure after installing Perl.
+C<perlivp> is a new Installation Verification Procedure utility
+for running any time after installing Perl.
=item *
-pod2html now allows specifying a cache directory.
+C<pod2html> now allows specifying a cache directory.
=item *
-s2p has been completely rewritten in Perl. (It is in fact a full
-implementation of sed in Perl.)
+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.)
=item *
-xsubpp now understands POD documentation embedded in the *.xs files.
+C<xsubpp> now understands POD documentation embedded in the *.xs files.
=item *
-xsubpp now supports OUT keyword.
+C<xsubpp> now supports OUT keyword.
=back
=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.
=item *
=item *
+perlpacktut is a pack() tutorial.
+
+=item *
+
perlpod has been rewritten to be clearer and to record the best
practices gathered over the years.
=item *
-perlpodstyle is a more formal specification of the pod format,
+perlpodspec is a more formal specification of the pod format,
mainly of interest for writers of pod applications, not to
people writing in pod.
=item *
-perlposix-bc explains using Perl on the POSIX-BC platform
-(an EBCDIC mainframe platform).
-
-=item *
-
perlretut is a regular expression tutorial.
=item *
=item *
-perluniintro is an introduction to using Unicode in Perl
-(perlunicode is more of a reference)
+perluniintro is an introduction to using Unicode in Perl.
+(perlunicode is more of a detailed reference and background
+information)
=item *
=item *
-map() that changes the size of the list should now work faster.
-
-=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).
+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 *
=item *
+Configure support for pdp11-style memory models has been removed due
+to obsolescence.
+
+=item *
+
configure.gnu now works with options with whitespace in them.
=item *
=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.
+
+=item *
+
For Perl developers several new make targets for profiling
and debugging have been added, see L<perlhack>.
=item *
+BeOS has been reclaimed.
+
+=item *
+
DG/UX platform now supports the 5.005-style threads. See L<perldgux>.
=item *
=item *
+All the NetBSD specific patches (except for the installation
+specific ones) have been merged back to the main distribution.
+
+=item *
+
NetWare from Novell is now supported. See L<perlnetware>.
=item *
=item *
+NEC SUPER-UX is now supported.
+
+=item *
+
+All the OpenBSD specific patches (except for the installation
+specific ones) have been merged back to the main distribution.
+
+=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 *
+
Amdahl UTS UNIX mainframe platform is now supported.
=item *
=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
=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.
+The autouse pragma didn't work for Multi::Part::Function::Names.
=item *
-C<*foo{FORMAT}> now works.
+caller() could cause core dumps in certain situations. Carp was sometimes
+affected by this problem.
=item *
-Lexical warnings now propagating correctly between scopes.
+chop(@list) in list context returned the characters chopped in
+reverse order. This has been reversed to be in the right order.
=item *
-Line renumbering with eval and C<#line> now works.
+Configure no longer includes the DBM libraries (dbm, gdbm, db, ndbm)
+when building the Perl binary. The only exception to this is SunOS 4.x,
+which needs them.
=item *
-Fixed numerous memory leaks, especially in eval "".
+The behaviour of non-decimal but numeric string constants such as
+"0x23" was platform-dependent: in some platforms that was seen as 35,
+in some as 0, in some as a floating point number (don't ask). This
+was caused by Perl using the operating system libraries in a situation
+where the result of the string to number conversion is undefined: now
+Perl consistently handles such strings as zero in numeric contexts.
=item *
-Modulus of unsigned numbers now works (4063328477 % 65535 used to
-return 27406, instead of 27047).
+The order of DESTROYs has been made more predictable.
=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.
+Several debugger fixes: exit code now reflects the script exit code,
+condition C<"0"> now treated correctly, the C<d> command now checks
+line number, the C<$.> no longer gets corrupted, all debugger output
+now goes correctly to the socket if RemotePort is set.
=item *
-our() variables will not cause "will not stay shared" warnings.
+Perl 5.6.0 could emit spurious warnings about redefinition of dl_error()
+when statically building extensions into perl. This has been corrected.
=item *
-pack "Z" now correctly terminates the string with "\0".
+L<dprofpp> -R didn't work.
=item *
-Fix password routines which in some shadow password platforms
-(e.g. HP-UX) caused getpwent() to return every other entry.
-
+C<*foo{FORMAT}> now works.
=item *
-printf() no longer resets the numeric locale to "C".
+Infinity is now recognized as a number.
=item *
-C<q(a\\b)> now parses correctly as C<'a\\b'>.
+UNIVERSAL::isa no longer caches methods incorrectly. (This broke
+the Tk extension with 5.6.0.)
=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).
+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 *
-Regular expressions on references and overloaded scalars now work.
+Lexicals II: lexicals leaked at file scope into subroutines that
+were declared before the lexicals.
=item *
-scalar() now forces scalar context even when used in void context.
+Lexical warnings now propagating correctly between scopes
+and into C<eval "...">.
=item *
-sort() arguments are now compiled in the right wantarray context
-(they were accidentally using the context of the sort() itself).
+C<use warnings qw(FATAL all)> did not work as intended. This has been
+corrected.
=item *
-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).
+warnings::enabled() now reports the state of $^W correctly if the caller
+isn't using lexical warnings.
=item *
-$AUTOLOAD, sort(), lock(), and spawning subprocesses
-in multiple threads simultaneously are now thread-safe.
+Line renumbering with eval and C<#line> now works.
=item *
-Allow read-only string on left hand side of non-modifying tr///.
+Fixed numerous memory leaks, especially in eval "".
=item *
-Several Unicode fixes (but still not perfect).
-
-=over 8
+mkdir() now ignores trailing slashes in the directory name,
+as mandated by POSIX.
=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.
+Some versions of glibc have a broken modfl(). This affects builds
+with C<-Duselongdouble>. This version of Perl detects this brokenness
+and has a workaround for it. The glibc release 2.2.2 is known to have
+fixed the modfl() bug.
=item *
-The character tables have been updated to Unicode 3.0.1.
+Modulus of unsigned numbers now works (4063328477 % 65535 used to
+return 27406, instead of 27047).
=item *
-chr() for values greater than 127 now create utf8 when under use
-utf8.
+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 *
-Comparing with utf8 data does not magically upgrade non-utf8 data into
-utf8.
+Numeric conversions did not recognize changes in the string value
+properly in certain circumstances.
=item *
-C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
+Attributes (like :shared) didn't work with our().
=item *
-Concatenation with the C<.> operator or via variable interpolation,
-C<eq>, C<substr>, C<reverse>, C<quotemeta>, the C<x> operator,
-substitution with C<s///>, single-quoted UTF8, should now work--in
-theory.
+our() variables will not cause "will not stay shared" warnings.
=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', ...)).
+"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 *
-vec() now refuses to deal with characters >255.
+pack "Z" now correctly terminates the string with "\0".
=item *
-Zero entries were missing from the Unicode classes like C<IsDigit>.
-
-=back
+Fix password routines which in some shadow password platforms
+(e.g. HP-UX) caused getpwent() to return every other entry.
=item *
-UNIVERSAL::isa no longer caches methods incorrectly. (This broke
-the Tk extension with 5.6.0.)
+The PERL5OPT environment variable (for passing command line arguments
+to Perl) didn't work for more than a single group of options.
=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.
+PERL5OPT with embedded spaces didn't work.
=item *
-SOCKS support is now much more robust.
+printf() no longer resets the numeric locale to "C".
=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 ...
+C<qw(a\\b)> now parses correctly as C<'a\\b'>.
-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
+pos() did not return the correct value within s///ge in earlier
+versions. This is now handled correctly.
-and Perl will be built and tested, all in /tmp/perl/build/directory.
+=item *
-=back
+Printing quads (64-bit integers) with printf/sprintf now works
+without the q L ll prefixes (assuming you are on a quad-capable platform).
-=head2 Platform Specific Changes and Fixes
+=item *
-=over 4
+Regular expressions on references and overloaded scalars now work.
=item *
-BSDI 4.*
-
-Perl now works on post-4.0 BSD/OSes.
+Right-hand side magic (GMAGIC) could in many cases such as string
+concatenation be invoked too many times.
=item *
-All BSDs
-
-Setting C<$0> now works (as much as possible; see perlvar for details).
+scalar() now forces scalar context even when used in void context.
=item *
-Cygwin
-
-Numerous updates; currently synchronised with Cygwin 1.1.4.
+SOCKS support is now much more robust.
=item *
-EPOC
-
-EPOC update after Perl 5.6.0. See README.epoc.
+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 *
-FreeBSD 3.*
-
-Perl now works on post-3.0 FreeBSDs.
+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 *
-HP-UX
-
-README.hpux updated; C<Configure -Duse64bitall> now almost works.
+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 *
-IRIX
-
-Numerous compilation flag and hint enhancements; accidental mixing
-of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
+Some cases of inconsistent taint propagation (such as within hash
+values) have been fixed.
=item *
-Linux
-
-Long doubles should now work (see INSTALL).
+The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds
+of simple pattern matches. These are now handled better.
=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.
+Regular expression debug output (whether through C<use re 'debug'>
+or via C<-Dr>) now looks better.
=item *
-MPE/iX
-
-MPE/iX update after Perl 5.6.0. See README.mpeix.
+Multi-line matches like C<"a\nxb\n" =~ /(?!\A)x/m> were flawed. The
+bug has been fixed.
=item *
-NetBSD/sparc
-
-Perl now works on NetBSD/sparc.
+Use of $& could trigger a core dump under some situations. This
+is now avoided.
=item *
-OS/2
-
-Now works with usethreads (see INSTALL).
+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 *
-Solaris
-
-64-bitness using the Sun Workshop compiler now works.
+readline() on files opened in "slurp" mode could return an extra "" at
+the end in certain situations. This has been corrected.
=item *
-Tru64 (aka Digital UNIX, aka DEC OSF/1)
-
-The operating system version letter now recorded in $Config{osvers}.
-Allow compiling with gcc (previously explicitly forbidden). Compiling
-with gcc still not recommended because buggy code results, even with
-gcc 2.95.2.
+Autovivification of symbolic references of special variables described
+in L<perlvar> (as in C<${$num}>) was accidentally disabled. This works
+again now.
=item *
-Unicos
-
-Fixed various alignment problems that lead into core dumps either
-during build or later; no longer dies on math errors at runtime;
-now using full quad integers (64 bits), previously was using
-only 46 bit integers for speed.
+Sys::Syslog ignored the C<LOG_AUTH> constant.
=item *
-VMS
-
-chdir() now works better despite a CRT bug; now works with MULTIPLICITY
-(see INSTALL); now works with Perl's malloc.
+All but the first argument of the IO syswrite() method are now optional.
=item *
-Windows
-
-=over 8
+$AUTOLOAD, sort(), lock(), and spawning subprocesses
+in multiple threads simultaneously are now thread-safe.
=item *
-accept() no longer leaks memory.
+Tie::ARRAY SPLICE method was broken.
=item *
-Better chdir() return value for a non-existent directory.
+Allow read-only string on left hand side of non-modifying tr///.
=item *
-New %ENV entries now propagate to subprocesses.
+Several Unicode fixes.
+
+=over 8
=item *
-$ENV{LIB} now used to search for libs under Visual C.
+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 *
-A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
+The character tables have been updated to Unicode 3.1.1.
=item *
-Allow REG_EXPAND_SZ keys in the registry.
+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 *
-Can now send() from all threads, not just the first one.
+Generating illegal Unicode code points like U+FFFE, or the UTF-16
+surrogates, now also generates an optional warning.
=item *
-Fake signal handling reenabled, bugs and all.
+C<IsAlnum>, C<IsAlpha>, and C<IsWord> now match titlecase.
=item *
-Less stack reserved per thread so that more threads can run
-concurrently. (Still 16M per thread.)
+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 *
-C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
-(works better when perl is running as service).
+The C<tr///> operator now works. Note that the C<tr///CU>
+functionality has been removed (but see pack('U0', ...)).
=item *
-Better UNC path handling under ithreads.
+C<eval "v200"> now works.
=item *
-wait() and waitpid() now work much better.
+Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
+This has been corrected.
=item *
-winsock handle leak fixed.
+Zero entries were missing from the Unicode classes like C<IsDigit>.
=back
+=item *
+
+Large unsigned numbers (those above 2**31) could sometimes lose their
+unsignedness, causing bogus results in arithmetic operations.
+
=back
-=head1 New or Changed Diagnostics
+=head2 Platform Specific Changes and Fixes
-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.
+=over 4
-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.
+BSDI 4.*
-=over 4
+Perl now works on post-4.0 BSD/OSes.
-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 *
+
+All BSDs
+
+Setting C<$0> now works (as much as possible; see L<perlvar> for details).
=item *
-If an attempt to use a (non-blessed) reference as an array index
-is made, a warning is given.
+Cygwin
+
+Numerous updates; currently synchronised with Cygwin 1.1.4.
=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.
+Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
-=back
+=item *
-=head1 Changed Internals
+EPOC
-=over 4
+EPOC update after Perl 5.6.0. See README.epoc.
=item *
-perlapi.pod (a companion to perlguts) now attempts to document the
-internal API.
+FreeBSD 3.*
+
+Perl now works on post-3.0 FreeBSDs.
=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.
+HP-UX
+
+README.hpux updated; C<Configure -Duse64bitall> now almost works.
=item *
-Added rsignal(), whichsig(), do_join() to the publicised API.
+IRIX
+
+Numerous compilation flag and hint enhancements; accidental mixing
+of 32-bit and 64-bit libraries (a doomed attempt) made much harder.
=item *
-Made possible to propagate customised exceptions via croak()ing.
+Linux
+
+=over 8
=item *
-Added is_utf8_char(), is_utf8_string(), bytes_to_utf8(), and utf8_to_bytes().
+Long doubles should now work (see INSTALL).
=item *
-Now xsubs can have attributes just like subs.
+Linux previously had problems related to sockaddrlen when using
+accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
+
+=back
=item *
-Some new APIs: ptr_table_clear(), ptr_table_free(), sv_setref_uv().
-For the full list of the available APIs see L<perlapi>.
+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 *
-dTHR and djSP have been obsoleted; the former removed (because it's
-a no-op) and the latter replaced with dSP.
+MPE/iX
+
+MPE/iX update after Perl 5.6.0. See README.mpeix.
=item *
-PERL_OBJECT has been completely removed.
+NetBSD/sparc
+
+Perl now works on NetBSD/sparc.
=item *
-Documentation on how to use the Perl source repository has been added
-to F<Porting/repository.pod>.
+OS/2
+
+Now works with usethreads (see INSTALL).
=item *
-There are now several profiling make targets
+Solaris
+
+64-bitness using the Sun Workshop compiler now works.
=item *
-The C<op_clear> and C<op_null> are now exported.
+Tru64 (aka Digital UNIX, aka DEC OSF/1)
-=back
+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.
-=head1 Security Vulnerability Closed
+=item *
-(This change was already made in 5.7.0 but bears repeating here.)
+Unicos
-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.
+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.
-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
-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 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/).
+VMS
-=head1 Selected Bug Fixes
+chdir() now works better despite a CRT bug; now works with MULTIPLICITY
+(see INSTALL); now works with Perl's malloc.
-Numerous memory leaks and uninitialized memory accesses have been hunted down.
-Most importantly anonymous subs used to leak quite a bit.
+The tainting of C<%ENV> elements via C<keys> or C<values> was previously
+unimplemented. It now works as documented.
-=over 4
+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.
+
+POSIX-style signals are now emulated much better on VMS versions prior
+to 7.0.
+
+The C<system> function and backticks operator have improved
+functionality and better error handling.
=item *
-chop(@list) in list context returned the characters chopped in
-reverse order. This has been reversed to be in the right order.
+Windows
+
+=over 8
=item *
-The order of DESTROYs has been made more predictable.
+accept() no longer leaks memory.
=item *
-mkdir() now ignores trailing slashes in the directory name,
-as mandated by POSIX.
+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 *
-Attributes (like :shared) didn't work with our().
+Better chdir() return value for a non-existent directory.
=item *
-The PERL5OPT environment variable (for passing command line arguments
-to Perl) didn't work for more than a single group of options.
+Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
=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.
+New %ENV entries now propagate to subprocesses.
=item *
-All but the first argument of the IO syswrite() method are now optional.
+Current directory entries in %ENV are now correctly propagated to child
+processes.
=item *
-Tie::ARRAY SPLICE method was broken.
+$ENV{LIB} now used to search for libs under Visual C.
=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.
+fork() emulation has been improved in various ways, but still continues
+to be experimental. See L<perlfork> for known bugs and caveats.
=item *
-The autouse pragma didn't work for Multi::Part::Function::Names.
+A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
=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.
+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 *
-L<dprofpp> -R didn't work.
+HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
=item *
-PERL5OPT with embedded spaces didn't work.
+The makefiles now provide a single switch to bulk-enable all the features
+enabled in ActiveState ActivePerl (a popular Win32 binary distribution).
=item *
-L<Sys::Syslog> ignored the C<LOG_AUTH> constant.
+Allow REG_EXPAND_SZ keys in the registry.
=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.
+Can now send() from all threads, not just the first one.
=item *
-Linux previously had problems related to sockaddrlen when using
-accept(), revcfrom() (in Perl: recv()), getpeername(), and getsockname().
+Fake signal handling reenabled, bugs and all.
=item *
-Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O.
+%SIG has been enabled under USE_ITHREADS, but its use is completely
+unsupported under all configurations.
=item *
-Windows
+Less stack reserved per thread so that more threads can run
+concurrently. (Still 16M per thread.)
-=over 8
+=item *
+
+C<File::Spec->tmpdir()> now prefers C:/temp over /tmp
+(works better when perl is running as service).
=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++).
+Better UNC path handling under ithreads.
=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.
+wait(), waitpid() and backticks now return the correct exit status under
+Windows 9x.
=item *
-Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x.
+winsock handle leak fixed.
+
+=back
+
+=back
+
+=head1 New or Changed Diagnostics
+
+=over 4
=item *
-HTML files will be installed in c:\perl\html instead of c:\perl\lib\pod\html
+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 makefiles now provide a single switch to bulk-enable all the features
-enabled in ActiveState ActivePerl (a popular binary distribution).
+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>.
-=back
+=item *
-=head1 New Tests
+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.
-Several new tests have been added, especially for the F<lib> subsection.
+=item *
-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
-to be closer to the library/extension they are testing.)
+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.
-=head1 New or Changed Diagnostics
+=item *
-=over 4
+If an attempt to use a (non-blessed) reference as an array index
+is made, a warning is given.
=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.
+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 *
=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.
+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
-=head1 Source Code Enhancements
+=head1 Changed Internals
+
+=over 4
+
+=item *
+
+perlapi.pod (a companion to perlguts) now attempts to document the
+internal API.
-=head2 MAGIC constants
+=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.
+
+=item *
+
+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 *
+
+Made possible to propagate customised exceptions via croak()ing.
+
+=item *
+
+Now xsubs can have attributes just like subs. (Well, at least the
+built-in attributes.)
+
+=item *
+
+dTHR and djSP have been obsoleted; the former removed (because it's
+a no-op) and the latter replaced with dSP.
+
+=item *
+
+PERL_OBJECT has been completely removed.
+
+=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.
-=head1 Known Problems
+=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>.
-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.
+=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. 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
+to be closer to the library/extension they are testing.)
+
+=head1 Known Problems
=head2 AIX
=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
projects / p5sagit/p5-mst-13.2.git / blobdiff