NAME¶
perl58delta - what is new for perl v5.8.0
DESCRIPTION¶
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 (while 5.8.0 was
still called 5.7.something).
Changes that were integrated into the 5.6.1 release are marked
"[561]". Many of these changes have been further developed since
5.6.1 was released, those are marked "[561+]".
You can see the list of changes in the 5.6.1 release (both from the 5.005_03
release and the 5.6.0 release) by reading perl561delta.
Highlights In 5.8.0¶
- •
- Better Unicode support
- •
- New IO Implementation
- •
- New Thread Implementation
- •
- Better Numeric Accuracy
- •
- Safe Signals
- •
- Many New Modules
- •
- More Extensive Regression Testing
Incompatible Changes¶
Binary Incompatibility¶
Perl 5.8 is not binary compatible with earlier releases of Perl.
You have to recompile your XS modules.
(Pure Perl modules should continue to work.)
The major reason for the discontinuity is the new IO architecture called PerlIO.
PerlIO is the default configuration because without it many new features of
Perl 5.8 cannot be used. In other words: you just have to recompile your
modules containing XS code, sorry about that.
In future releases of Perl, non-PerlIO aware XS modules may become completely
unsupported. This shouldn't be too difficult for module authors, however:
PerlIO has been designed as a drop-in replacement (at the source code level)
for the stdio interface.
Depending on your platform, there are also other reasons why we decided to break
binary compatibility, please read on.
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
(such as mod_perl) tend to prefer the system malloc. Such platforms include
Alpha and 64-bit HPPA, MIPS, PPC, and Sparc.
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 mod_perl which
are using the AIX native interface.
Attributes for "my" variables now handled at run-time¶
The "my EXPR : ATTRS" syntax now applies variable attributes at
run-time. (Subroutine and "our" variables still get attributes
applied at compile-time.) See attributes for additional details. In
particular, however, this allows variable attributes to be useful for
"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).
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.
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.
New Unicode Semantics (no more "use utf8", almost)¶
Previously in Perl 5.6 to use Unicode one would say "use utf8" and
then the operations (like string concatenation) were Unicode-aware in that
lexical scope.
This was found to be an inconvenient interface, and in Perl 5.8 the Unicode
model has completely changed: now the "Unicodeness" is bound to the
data itself, and for most of the time "use utf8" is not needed at
all. The only remaining use of "use utf8" is when the Perl script
itself has been written in the UTF-8 encoding of Unicode. (UTF-8 has not been
made the default since there are many Perl scripts out there that are using
various national eight-bit character sets, which would be illegal in UTF-8.)
See perluniintro for the explanation of the current model, and utf8 for the
current use of the utf8 pragma.
New Unicode Properties¶
Unicode
scripts are now supported. Scripts are similar to (and superior
to) Unicode
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 "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 "Latin").
A number of other properties are now supported, including
"\p{L&}", "\p{Any}" "\p{Assigned}",
"\p{Unassigned}", "\p{Blank}" [561] and
"\p{SpacePerl}" [561] (along with their "\P{...}"
versions, of course). See perlunicode for details, and more additions.
The "In" or "Is" prefix to names used with the
"\p{...}" and "\P{...}" are now almost always optional.
The only exception is that a "In" prefix is required to signify a
Unicode block when a block name conflicts with a script name. For example,
"\p{Tibetan}" refers to the script, while "\p{InTibetan}"
refers to the block. When there is no name conflict, you can omit the
"In" from the block name (e.g. "\p{BraillePatterns}"), but
to be safe, it's probably best to always use the "In").
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().
pack/unpack D/F recycled¶
The undocumented pack/unpack template letters D/F have been recycled for better
use: now they stand for long double (if supported by the platform) and NV
(Perl internal floating point type). (They used to be aliases for d/f, but you
never knew that.)
glob() now returns filenames in alphabetical order¶
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.) [561]
Deprecations¶
- •
- The semantics of bless(REF, REF) were unclear and until someone proves it
to make some sense, it is forbidden.
- •
- The obsolete chat2 library that should never have been allowed to escape
the laboratory has been decommissioned.
- •
- Using chdir("") or chdir(undef) instead of explicit
chdir() is doubtful. A failure (think chdir(
some_function()) can lead into unintended chdir() to the
home directory, therefore this behaviour is deprecated.
- •
- 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 "CORE::dump()", but in future releases
the behaviour of an unqualified "dump()" call may change.
- •
- 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 (bogus) escape sequences \8 and \9 now give an optional warning
("Unrecognized escape passed through"). There is no need to
\-escape any "\w" character.
- •
- The *glob{FILEHANDLE} is deprecated, use *glob{IO} instead.
- •
- The "package;" syntax ("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, "use strict;" instead.
- •
- 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.
- •
- In future releases, non-PerlIO aware XS modules may become completely
unsupported. Since PerlIO is a drop-in replacement for stdio at the source
code level, this shouldn't be that drastic a change.
- •
- Previous versions of perl and some readings of some sections of Camel III
implied that the ":raw" "discipline" was the inverse
of ":crlf". Turning off "clrfness" is no longer enough
to make a stream truly binary. So the PerlIO ":raw" layer (or
"discipline", to use the Camel book's older terminology) is now
formally defined as being equivalent to binmode(FH) - which is in turn
defined as doing whatever is necessary to pass each byte as-is without any
translation. In particular binmode(FH) - and hence ":raw" - will
now turn off both CRLF and UTF-8 translation and remove other layers (e.g.
: encoding()) which would modify byte stream.
- •
- 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 "fields" pragma interface will remain available.
The restricted hashes interface is expected to be the replacement
interface (see Hash::Util). If your existing programs depends on the
underlying implementation, consider using Class::PseudoHash from
CPAN.
- •
- The syntaxes "@a->[...]" and "%h->{...}" have
now been deprecated.
- •
- After years of trying, 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.
- •
- The 5.005 threads model (module "Thread") is deprecated and
expected to be removed in Perl 5.10. Multithreaded code should be migrated
to the new ithreads model (see threads, threads::shared and
perlthrtut).
- •
- The long deprecated uppercase aliases for the string comparison operators
(EQ, NE, LT, LE, GE, GT) have now been removed.
- •
- 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', ...). [561]
- •
- Earlier Perls treated "sub foo (@bar)" as equivalent to
"sub foo (@)". The prototypes are now checked better at
compile-time for invalid syntax. An optional warning is generated
("Illegal character in prototype...") but this may be upgraded
to a fatal error in a future release.
- •
- The "exec LIST" and "system LIST" operations now
produce warnings on tainted data and in some future release they will
produce fatal errors.
- •
- The existing behaviour when localising tied arrays and hashes is wrong,
and will be changed in a future release, so do not rely on the existing
behaviour. See "Localising Tied Arrays and Hashes Is
Broken".
Core Enhancements¶
Unicode Overhaul¶
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. See perluniintro for introduction and perlunicode for details.
- •
- The Unicode Character Database coming with Perl has been upgraded to
Unicode 3.2.0. For more information, see http://www.unicode.org/ . [561+]
(5.6.1 has UCD 3.0.1.)
- •
- For developers interested in enhancing Perl's Unicode capabilities: almost
all the UCD files are included with the Perl distribution in the
lib/unicore subdirectory. The most notable omission, for space
considerations, is the Unihan database.
- •
- 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
"\s" (\p{Space} isn't, since that includes the vertical
tabulator character, whereas "\s" doesn't.)
See "New Unicode Properties" earlier in this document for
additional information on changes with Unicode properties.
PerlIO is Now The Default¶
- •
- 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:
open($fh,'>:crlf :utf8', $path) || ...
or on already opened handles via extended "binmode":
binmode($fh,':encoding(iso-8859-7)');
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).
Layers to be applied by default may be specified via the 'open' pragma.
See "Installation and Configuration Improvements" for the effects
of PerlIO on your architecture name.
- •
- If your platform supports fork(), you can use the list form of
"open" for pipes. For example:
open KID_PS, "-|", "ps", "aux" or die $!;
forks the ps(1) command (without spawning a shell, as there are more
than three arguments to open()), and reads its standard output via
the "KID_PS" filehandle. See perlipc.
- •
- File handles can be marked as accepting Perl's internal encoding of
Unicode (UTF-8 or UTF-EBCDIC depending on platform) by a pseudo layer
":utf8" :
open($fh,">:utf8","Uni.txt");
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 perlunicode, utf8, and
http://www.unicode.org/unicode/reports/tr16/ for more information. In
future releases this naming may change. See perluniintro for more
information about UTF-8.
- •
- If your environment variables (LC_ALL, LC_CTYPE, LANG) look like you want
to use UTF-8 (any of the variables match "/utf-?8/i"), your
STDIN, STDOUT, STDERR handles and the default open layer (see open) are
marked as UTF-8. (This feature, like other new features that combine
Unicode and I/O, work only if you are using PerlIO, but that's the
default.)
Note that after this Perl really does assume that everything is UTF-8: for
example if some input handle is not, Perl will probably very soon complain
about the input data like this "Malformed UTF-8 ..." since any
old eight-bit data is not legal UTF-8.
Note for code authors: if you want to enable your users to use UTF-8 as
their default encoding but in your code still have eight-bit I/O streams
(such as images or zip files), you need to explicitly open() or
binmode() with ":bytes" (see "open" in perlfunc
and "binmode" in perlfunc), or you can just use
"binmode(FH)" (nice for pre-5.8.0 backward compatibility).
- •
- File handles can translate character encodings from/to Perl's internal
Unicode form on read/write via the ": encoding()"
layer.
- •
- File handles can be opened to "in memory" files held in Perl
scalars via:
open($fh,'>', \$variable) || ...
- •
- Anonymous temporary files are available without need to 'use FileHandle'
or other module via
open($fh,"+>", undef) || ...
That is a literal undef, not an undefined value.
ithreads¶
The new interpreter threads ("ithreads" for short) implementation of
multithreading, by Arthur Bergman, replaces the old "5.005 threads"
implementation. In the ithreads model any data sharing between threads must be
explicit, as opposed to the model where data sharing was implicit. See threads
and threads::shared, and perlthrtut.
As a part of the ithreads implementation Perl will also use any necessary and
detectable reentrant libc interfaces.
Restricted Hashes¶
A restricted hash is restricted to a certain set of keys, no keys outside the
set can be added. Also individual keys can be restricted so that the key
cannot be deleted and the value cannot be changed. No new syntax is involved:
the Hash::Util module is the interface.
Safe Signals¶
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).
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. Note that breaking out from potentially blocking operations should
still work, though.
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 "strtoul()" and "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.)
Arrays now always interpolate into double-quoted strings [561]¶
In double-quoted strings, arrays now interpolate, no matter what. The behavior
in earlier versions of perl 5 was that arrays would interpolate into strings
if the array had been mentioned before the string was compiled, and otherwise
Perl would raise a fatal compile-time error. In versions 5.000 through 5.003,
the error was
Literal @example now requires backslash
In versions 5.004_01 through 5.6.0, the error was
In string, @example now must be written as \@example
The idea here was to get people into the habit of writing
"fred\@example.com" when they wanted a literal "@" sign,
just as they have always written "Give me back my \$5" when they
wanted a literal "$" sign.
Starting with 5.6.1, when Perl now sees an "@" sign in a double-quoted
string, it
always attempts to interpolate an array, regardless of
whether or not the array has been used or declared already. The fatal error
has been downgraded to an optional warning:
Possible unintended interpolation of @example in string
This warns you that "fred@example.com" is going to turn into
"fred.com" if you don't backslash the "@". See
http://perl.plover.com/at-error.html for more details about the history here.
Miscellaneous Changes¶
- •
- AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute
to AUTOLOAD subroutines and you can assign to the AUTOLOAD return
value.
- •
- The $Config{byteorder} (and corresponding BYTEORDER in config.h) was
previously wrong in platforms if sizeof(long) was 4, but sizeof(IV) was 8.
The byteorder was only sizeof(long) bytes long (1234 or 4321), but now it
is correctly sizeof(IV) bytes long, (12345678 or 87654321). (This problem
didn't affect Windows platforms.)
Also, $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, and when cross-compiling.
- •
- "perl -d:Module=arg,arg,arg" now works (previously one couldn't
pass in multiple arguments.)
- •
- "do" followed by a bareword now ensures that this bareword isn't
a keyword (to avoid a bug where "do q(foo.pl)" tried to call a
subroutine called "q"). This means that for example instead of
"do format()" you must write "do &format()".
- •
- The builtin dump() now gives an optional warning "dump()
better written as CORE::dump()", meaning that by default
"dump(...)" is resolved as the builtin dump() which dumps
core and aborts, not as (possibly) user-defined "sub dump". To
call the latter, qualify the call as "&dump(...)". (The
whole dump() feature is to considered deprecated, and possibly
removed/changed in future releases.)
- •
- chomp() and chop() are now overridable. Note, however, that
their prototype (as given by
"prototype("CORE::chomp")" is undefined, because it
cannot be expressed and therefore one cannot really write replacements to
override these builtins.
- •
- 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 perlembed.
- •
- Formats now support zero-padded decimal fields.
- •
- 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 "Performance Enhancements".
- •
- lstat(FILEHANDLE) now gives a warning because the operation makes no
sense. In future releases this may become a fatal error.
- •
- Spurious syntax errors generated in certain situations, when glob()
caused File::Glob to be loaded for the first time, have been fixed.
[561]
- •
- Lvalue subroutines can now return "undef" in list context.
However, the lvalue subroutine feature still remains experimental.
[561+]
- •
- A lost warning "Can't declare ... dereference in my" has been
restored (Perl had it earlier but it became lost in later releases.)
- •
- A new special regular expression variable has been introduced: $^N, which
contains the most-recently closed group (submatch).
- •
- "no Module;" does not produce an error even if Module does not
have an unimport() method. This parallels the behavior of
"use" vis-a-vis "import". [561]
- •
- The numerical comparison operators return "undef" if either
operand is a NaN. Previously the behaviour was unspecified.
- •
- "our" can now have an experimental optional attribute
"unique" that affects how global variables are shared among
multiple interpreters, see "our" in perlfunc.
- •
- The following builtin functions are now overridable: each(),
keys(), pop(), push(), shift(),
splice(), unshift(). [561]
- •
- "pack() / unpack()" can now group template letters with
"()" and then apply repetition/count modifiers on the
groups.
- •
- "pack() / unpack()" can now process the Perl internal numeric
types: IVs, UVs, NVs-- and also long doubles, if supported by the
platform. The template letters are "j", "J",
"F", and "D".
- •
- "pack('U0a*', ...)" can now be used to force a string to
UTF-8.
- •
- my __PACKAGE__ $obj now works. [561]
- •
- POSIX::sleep() now returns the number of unslept seconds (as
the POSIX standard says), as opposed to CORE::sleep() which returns
the number of slept seconds.
- •
- printf() and sprintf() now support parameter reordering
using the "%\d+\$" and "*\d+\$" syntaxes. For example
printf "%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.
- •
- The (\&) prototype now works properly. [561]
- •
- prototype(\[$@%&]) is now available to implicitly create references
(useful for example if you want to emulate the tie()
interface).
- •
- A new command-line option, "-t" is available. It is the little
brother of "-T": instead of dying on taint violations, lexical
warnings are given. This is only meant as a temporary debugging
aid while securing the code of old legacy applications. This is not
a substitute for -T.
- •
- In other taint news, the "exec LIST" and "system LIST"
have now been considered too risky (think "exec @ARGV": it can
start any program with any arguments), and now the said forms cause a
warning under lexical warnings. You should carefully launder the arguments
to guarantee their validity. In future releases of Perl the forms will
become fatal errors so consider starting laundering now.
- •
- Tied hash interfaces are now required to have the EXISTS and DELETE
methods (either own or inherited).
- •
- If tr/// is just counting characters, it doesn't attempt to modify its
target.
- •
- untie() will now call an UNTIE() hook if it exists. See
perltie for details. [561]
- •
- "utime" in perlfunc now supports "utime undef, undef,
@files" to change the file timestamps to the current time.
- •
- The rules for allowing underscores (underbars) in numeric constants have
been relaxed and simplified: now you can have an underscore simply
between digits.
- •
- Rather than relying on C's argv[0] (which may not contain a full pathname)
where possible $^X is now set by asking the operating system. (eg by
reading /proc/self/exe on Linux, /proc/curproc/file on
FreeBSD)
- •
- A new variable, "${^TAINT}", indicates whether taint mode is
enabled.
- •
- You can now override the readline() builtin, and this overrides
also the <FILEHANDLE> angle bracket operator.
- •
- The command-line options -s and -F are now recognized on the shebang (#!)
line.
- •
- Use of the "/c" match modifier without an accompanying
"/g" modifier elicits a new warning: "Use of /c modifier is
meaningless without /g".
Use of "/c" in substitutions, even with "/g", elicits
"Use of /c modifier is meaningless in s///".
Use of "/g" with "split" elicits "Use of /g
modifier is meaningless in split".
- •
- Support for the "CLONE" special subroutine had been added. With
ithreads, when a new thread is created, all Perl data is cloned, however
non-Perl data cannot be cloned automatically. In "CLONE" you can
do whatever you need to do, like for example handle the cloning of
non-Perl data, if necessary. "CLONE" will be executed once for
every package that has it defined or inherited. It will be called in the
context of the new thread, so all modifications are made in the new area.
See perlmod
Modules and Pragmata¶
New Modules and Pragmata¶
- •
- "Attribute::Handlers", originally by Damian Conway and now
maintained by Arthur Bergman, allows a class to define attribute handlers.
package MyPack;
use Attribute::Handlers;
sub Wolf :ATTR(SCALAR) { print "howl!\n" }
# 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). See
Attribute::Handlers.
- •
- "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 B::Concise. [561+]
- •
- The new bignum, bigint, and bigrat pragmas, by Tels, implement transparent
bignum support (using the Math::BigInt, Math::BigFloat, and Math::BigRat
backends).
- •
- "Class::ISA", by Sean Burke, is a module for reporting the
search path for a class's ISA tree. See Class::ISA.
- •
- "Cwd" now has 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.
- •
- "Devel::PPPort", originally by Kenneth Albanowski and now
maintained by Paul Marquess, has been added. It is primarily used by
"h2xs" to enhance portability of XS modules between different
versions of Perl. See Devel::PPPort.
- •
- "Digest", frontend module for calculating digests (checksums),
from Gisle Aas, has been added. See Digest.
- •
- "Digest::MD5" for calculating MD5 digests (checksums) as defined
in RFC 1321, from Gisle Aas, has been added. See Digest::MD5.
use Digest::MD5 'md5_hex';
$digest = md5_hex("Thirsty Camel");
print $digest, "\n"; # 01d19d9d2045e005c3f1b80e8b164de1
NOTE: the "MD5" backward compatibility module is deliberately not
included since its further use is discouraged.
See also PerlIO::via::QuotedPrint.
- •
- "Encode", originally by Nick Ing-Simmons and now maintained by
Dan Kogai, provides a mechanism to translate between different character
encodings. Support for Unicode, ISO-8859-1, and ASCII are compiled in to
the module. Several other encodings (like the rest of the ISO-8859,
CP*/Win*, Mac, KOI8-R, three variants EBCDIC, Chinese, Japanese, and
Korean encodings) are included and can be loaded at runtime. (For space
considerations, the largest Chinese encodings have been separated into
their own CPAN module, Encode::HanExtra, which Encode will use if
available). See Encode.
Any encoding supported by Encode module is also available to the ":
encoding()" layer if PerlIO is used.
- •
- "Hash::Util" is the interface to the new restricted
hashes feature. (Implemented by Jeffrey Friedl, Nick Ing-Simmons, and
Michael Schwern.) See Hash::Util.
- •
- "I18N::Langinfo" can be used to query locale information. See
I18N::Langinfo.
- •
- "I18N::LangTags", by Sean Burke, has functions for dealing with
RFC3066-style language tags. See I18N::LangTags.
- •
- "ExtUtils::Constant", by Nicholas Clark, is a new tool for
extension writers for generating XS code to import C header constants. See
ExtUtils::Constant.
- •
- "Filter::Simple", by Damian Conway, is an easy-to-use frontend
to Filter::Util::Call. See Filter::Simple.
# in MyFilter.pm:
package MyFilter;
use Filter::Simple sub {
while (my ($from, $to) = splice @_, 0, 2) {
s/$from/$to/g;
}
};
1;
# in user's code:
use MyFilter qr/red/ => 'green';
print "red\n"; # this code is filtered, will print "green\n"
print "bored\n"; # this code is filtered, will print "bogreen\n"
no MyFilter;
print "red\n"; # this code is not filtered, will print "red\n"
- •
- "File::Temp", by Tim Jenness, allows one to create temporary
files and directories in an easy, portable, and secure way. See
File::Temp. [561+]
- •
- "Filter::Util::Call", by Paul Marquess, provides you with the
framework to write source filters in Perl. For most uses, the
frontend Filter::Simple is to be preferred. See Filter::Util::Call.
- •
- "if", by Ilya Zakharevich, is a new pragma for conditional
inclusion of modules.
- •
- libnet, by Graham Barr, is a collection of perl5 modules related to
network programming. See Net::FTP, Net::NNTP, Net::Ping (not part of
libnet, but related), Net::POP3, Net::SMTP, and Net::Time.
Perl installation leaves libnet unconfigured; use libnetcfg to
configure it.
- •
- "List::Util", by Graham Barr, is a selection of general-utility
list subroutines, such as sum(), min(), first(), and
shuffle(). See List::Util.
- •
- "Locale::Constants", "Locale::Country",
"Locale::Currency" "Locale::Language", and
Locale::Script, by Neil Bowers, have been added. They provide the codes
for various locale standards, such as "fr" for France,
"usd" for US Dollar, and "ja" for Japanese.
use Locale::Country;
$country = code2country('jp'); # $country gets 'Japan'
$code = country2code('Norway'); # $code gets 'no'
See Locale::Constants, Locale::Country, Locale::Currency, and
Locale::Language.
- •
- "Locale::Maketext", by Sean Burke, is a localization framework.
See Locale::Maketext, and Locale::Maketext::TPJ13. The latter is an
article about software localization, originally published in The Perl
Journal #13, and republished here with kind permission.
- •
- "Math::BigRat" for big rational numbers, to accompany
Math::BigInt and Math::BigFloat, from Tels. See Math::BigRat.
- •
- "Memoize" can make your functions faster by trading space for
time, from Mark-Jason Dominus. See Memoize.
- •
- "MIME::Base64", by Gisle Aas, allows you to encode data in
base64, as defined in RFC 2045 - MIME (Multipurpose Internet Mail
Extensions).
use MIME::Base64;
$encoded = encode_base64('Aladdin:open sesame');
$decoded = decode_base64($encoded);
print $encoded, "\n"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ=="
See MIME::Base64.
- •
- "MIME::QuotedPrint", by Gisle Aas, allows you to encode data in
quoted-printable encoding, as defined in RFC 2045 - MIME
(Multipurpose Internet Mail Extensions).
use MIME::QuotedPrint;
$encoded = encode_qp("\xDE\xAD\xBE\xEF");
$decoded = decode_qp($encoded);
print $encoded, "\n"; # "=DE=AD=BE=EF\n"
print $decoded, "\n"; # "\xDE\xAD\xBE\xEF\n"
See also PerlIO::via::QuotedPrint.
- •
- "NEXT", by Damian Conway, is a pseudo-class for method
redispatch. See NEXT.
- •
- "open" is a new pragma for setting the default I/O layers for
open().
- •
- "PerlIO::scalar", by Nick Ing-Simmons, provides the
implementation of IO to "in memory" Perl scalars as discussed
above. It also serves as an example of a loadable PerlIO layer. Other
future possibilities include PerlIO::Array and PerlIO::Code. See
PerlIO::scalar.
- •
- "PerlIO::via", by Nick Ing-Simmons, acts as a PerlIO layer and
wraps PerlIO layer functionality provided by a class (typically
implemented in Perl code).
- •
- "PerlIO::via::QuotedPrint", by Elizabeth Mattijsen, is an
example of a "PerlIO::via" class:
use PerlIO::via::QuotedPrint;
open($fh,">:via(QuotedPrint)",$path);
This will automatically convert everything output to $fh to
Quoted-Printable. See PerlIO::via and PerlIO::via::QuotedPrint.
- •
- "Pod::ParseLink", by Russ Allbery, has been added, to parse
L<> links in pods as described in the new perlpodspec.
- •
- "Pod::Text::Overstrike", by Joe Smith, has been added. It
converts POD data to formatted overstrike text. See Pod::Text::Overstrike.
[561+]
- •
- "Scalar::Util" is a selection of general-utility scalar
subroutines, such as blessed(), reftype(), and
tainted(). See Scalar::Util.
- •
- "sort" is a new pragma for controlling the behaviour of
sort().
- •
- "Storable" gives persistence to Perl data structures by allowing
the storage and retrieval of Perl data to and from files in a fast and
compact binary format. Because in effect Storable does serialisation of
Perl data structures, with it you can also clone deep, hierarchical
datastructures. Storable was originally created by Raphael Manfredi, but
it is now maintained by Abhijit Menon-Sen. Storable has been enhanced to
understand the two new hash features, Unicode keys and restricted hashes.
See Storable.
- •
- "Switch", by Damian Conway, has been added. Just by saying
use Switch;
you have "switch" and "case" available in Perl.
use Switch;
switch ($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 Switch.
- •
- "Test::More", by Michael Schwern, is yet another framework for
writing test scripts, more extensive than Test::Simple. See
Test::More.
- •
- "Test::Simple", by Michael Schwern, has basic utilities for
writing tests. See Test::Simple.
- •
- "Text::Balanced", by Damian Conway, has been added, for
extracting delimited text sequences from strings.
use Text::Balanced 'extract_delimited';
($a, $b) = extract_delimited("'never say never', he never said", "'", '');
$a will be "'never say never'", $b will be ', he never said'.
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
Text::Balanced.
- •
- "threads", by Arthur Bergman, is an interface to interpreter
threads. 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 "fork()" emulation). See
threads, threads::shared, and perlthrtut.
- •
- "threads::shared", by Arthur Bergman, allows data sharing for
interpreter threads. See threads::shared.
- •
- "Tie::File", by Mark-Jason Dominus, associates a Perl array with
the lines of a file. See Tie::File.
- •
- "Tie::Memoize", by Ilya Zakharevich, provides on-demand loaded
hashes. See Tie::Memoize.
- •
- "Tie::RefHash::Nestable", by Edward Avis, allows storing hash
references (unlike the standard Tie::RefHash) The module is contained
within Tie::RefHash. See Tie::RefHash.
- •
- "Time::HiRes", by Douglas E. Wegscheid, provides high resolution
timing (ualarm, usleep, and gettimeofday). See Time::HiRes.
- •
- "Unicode::UCD" offers a querying interface to the Unicode
Character Database. See Unicode::UCD.
- •
- "Unicode::Collate", by SADAHIRO Tomoyuki, implements the UCA
(Unicode Collation Algorithm) for sorting Unicode strings. See
Unicode::Collate.
- •
- "Unicode::Normalize", by SADAHIRO Tomoyuki, implements the
various Unicode normalization forms. See Unicode::Normalize.
- •
- "XS::APItest", by Tim Jenness, is a test extension that
exercises XS APIs. Currently only "printf()" is tested: how to
output various basic data types from XS.
- •
- "XS::Typemap", by Tim Jenness, is a test extension that
exercises XS typemaps. Nothing gets installed, but the code is worth
studying for extension writers.
Updated And Improved Modules and Pragmata¶
- •
- 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 [561+], Pod::Parser, Storable,
Term::ANSIColor, Test, Text-Tabs+Wrap.
- •
- attributes::reftype() now works on tied arguments.
- •
- AutoLoader can now be disabled with "no AutoLoader;".
- •
- B::Deparse has been significantly enhanced by Robin Houston. It can now
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.
- •
- Carp now has better interface documentation, and the @CARP_NOT interface
has been added to get optional control over where errors are reported
independently of @ISA, by Ben Tilly.
- •
- Class::Struct can now define the classes in compile time.
- •
- Class::Struct now assigns the array/hash element if the accessor is called
with an array/hash element as the sole argument.
- •
- The return value of Cwd::fastcwd() is now tainted.
- •
- Data::Dumper now has an option to sort hashes.
- •
- Data::Dumper now has an option to dump code references using
B::Deparse.
- •
- DB_File now supports newer Berkeley DB versions, among other
improvements.
- •
- 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).
- •
- The English module can now be used without the infamous performance hit by
saying
use English '-no_match_vars';
(Assuming, of course, that you don't need the troublesome variables
"$`", $&, or "$'".) Also, introduced
@LAST_MATCH_START and @LAST_MATCH_END English aliases for "@-"
and "@+".
- •
- ExtUtils::MakeMaker has been significantly cleaned up and fixed. The
enhanced version has also been backported to earlier releases of Perl and
submitted to CPAN so that the earlier releases can enjoy the fixes.
- •
- The arguments of WriteMakefile() in Makefile.PL are now checked for
sanity much more carefully than before. This may cause new warnings when
modules are being installed. See ExtUtils::MakeMaker for more
details.
- •
- ExtUtils::MakeMaker now uses File::Spec internally, which hopefully leads
to better portability.
- •
- Fcntl, Socket, and Sys::Syslog have been rewritten by Nicholas Clark to
use the new-style constant dispatch section (see ExtUtils::Constant). This
means that they will be more robust and hopefully faster.
- •
- File::Find now chdir()s correctly when chasing symbolic links.
[561]
- •
- 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.
- •
- File::Find is now (again) reentrant. It also has been made more
portable.
- •
- The warnings issued by File::Find now belong to their own category. You
can enable/disable them with "use/no warnings
'File::Find';".
- •
- File::Glob::glob() has been renamed to
File::Glob::bsd_glob() because the name clashes with the builtin
glob(). The older name is still available for compatibility, but is
deprecated. [561]
- •
- File::Glob now supports "GLOB_LIMIT" constant to limit the size
of the returned list of filenames.
- •
- IPC::Open3 now allows the use of numeric file descriptors.
- •
- IO::Socket now has an 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.
- •
- IO::Socket::INET failed to open the specified port if the service name was
not known. It now correctly uses the supplied port number as is.
[561]
- •
- IO::Socket::INET has support for the ReusePort option (if your platform
supports it). The Reuse option now has an alias, ReuseAddr. For clarity,
you may want to prefer ReuseAddr.
- •
- IO::Socket::INET now supports a value of zero for "LocalPort"
(usually meaning that the operating system will make one up.)
- •
- 'use lib' now works identically to @INC. Removing directories with 'no
lib' now works.
- •
- Math::BigFloat and Math::BigInt have undergone a full rewrite by Tels.
They are now magnitudes faster, and they support various bignum libraries
such as GMP and PARI as their backends.
- •
- Math::Complex handles inf, NaN etc., better.
- •
- Net::Ping has been considerably enhanced by Rob Brown: multihoming is now
supported, Win32 functionality is better, there is now time measuring
functionality (optionally high-resolution using Time::HiRes), and there is
now "external" protocol which uses Net::Ping::External module
which runs your external ping utility and parses the output. A version of
Net::Ping::External is available in CPAN.
Note that some of the Net::Ping tests are disabled when running under the
Perl distribution since one cannot assume one or more of the following:
enabled echo port at localhost, full Internet connectivity, or sympathetic
firewalls. You can set the environment variable PERL_TEST_Net_Ping to
"1" (one) before running the Perl test suite to enable all the
Net::Ping tests.
- •
- 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.
- •
- In Safe, %INC is now localised in a Safe compartment so that use/require
work.
- •
- 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.
- •
- In Search::Dict one can now have a pre-processing hook for the lines being
searched.
- •
- The Shell module now has an OO interface.
- •
- In Sys::Syslog there is now a failover mechanism that will go through
alternative connection mechanisms until the message is successfully
logged.
- •
- The Test module has been significantly enhanced.
- •
- Time::Local::timelocal() does not handle fractional seconds
anymore. The rationale is that neither does localtime(), and
timelocal() and localtime() are supposed to be inverses of
each other.
- •
- The vars pragma now supports declaring fully qualified variables.
(Something that "our()" does not and will not support.)
- •
- 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.
Utility Changes¶
- •
- Emacs perl mode (emacs/cperl-mode.el) has been updated to version
4.31.
- •
- emacs/e2ctags.pl is now much faster.
- •
- "enc2xs" is a tool for people adding their own encodings to the
Encode module.
- •
- "h2ph" now supports C trigraphs.
- •
- "h2xs" now produces a template README.
- •
- "h2xs" now uses "Devel::PPPort" for better portability
between different versions of Perl.
- •
- "h2xs" uses the new 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 never got 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). h2xs now also supports C trigraphs.
- •
- "libnetcfg" has been added to configure libnet.
- •
- "perlbug" is now much more robust. It also sends the bug report
to perl.org, not perl.com.
- •
- "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 "perlcc -B" instead.) Note
that perlcc is still considered very experimental and
unsupported. [561]
- •
- "perlivp" is a new Installation Verification Procedure utility
for running any time after installing Perl.
- •
- "piconv" is an implementation of the character conversion
utility "iconv", demonstrating the new Encode module.
- •
- "pod2html" now allows specifying a cache directory.
- •
- "pod2html" now produces XHTML 1.0.
- •
- "pod2html" now understands POD written using different line
endings (PC-like CRLF versus Unix-like LF versus MacClassic-like CR).
- •
- "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 "psed" utility.)
- •
- "xsubpp" now understands POD documentation embedded in the *.xs
files. [561]
- •
- "xsubpp" now supports the OUT keyword.
New Documentation¶
- •
- perl56delta details the changes between the 5.005 release and the 5.6.0
release.
- •
- perlclib documents the internal replacements for standard C library
functions. (Interesting only for extension writers and Perl core hackers.)
[561+]
- •
- perldebtut is a Perl debugging tutorial. [561+]
- •
- perlebcdic contains considerations for running Perl on EBCDIC platforms.
[561+]
- •
- perlintro is a gentle introduction to Perl.
- •
- perliol documents the internals of PerlIO with layers.
- •
- perlmodstyle is a style guide for writing modules.
- •
- perlnewmod tells about writing and submitting a new module. [561+]
- •
- perlpacktut is a pack() tutorial.
- •
- perlpod has been rewritten to be clearer and to record the best practices
gathered over the years.
- •
- perlpodspec is a more formal specification of the pod format, mainly of
interest for writers of pod applications, not to people writing in
pod.
- •
- perlretut is a regular expression tutorial. [561+]
- •
- perlrequick is a regular expressions quick-start guide. Yes, much quicker
than perlretut. [561]
- •
- perltodo has been updated.
- •
- perltootc has been renamed as perltooc (to not to conflict with perltoot
in filesystems restricted to "8.3" names).
- •
- perluniintro is an introduction to using Unicode in Perl. (perlunicode is
more of a detailed reference and background information)
- •
- perlutil explains the command line utilities packaged with the Perl
distribution. [561+]
The following platform-specific documents are available before the installation
as README.
platform, and after the installation as perl
platform:
perlaix perlamiga perlapollo perlbeos perlbs2000
perlce perlcygwin perldgux perldos perlepoc perlfreebsd perlhpux
perlhurd perlirix perlmachten perlmacos perlmint perlmpeix
perlnetware perlos2 perlos390 perlplan9 perlqnx perlsolaris
perltru64 perluts perlvmesa perlvms perlvos perlwin32
These documents usually detail one or more of the following subjects:
configuring, building, testing, installing, and sometimes also using Perl on
the said platform.
Eastern Asian Perl users are now welcomed in their own languages: README.jp
(Japanese), README.ko (Korean), README.cn (simplified Chinese) and README.tw
(traditional Chinese), which are written in normal pod but encoded in EUC-JP,
EUC-KR, EUC-CN and Big5. These will get installed as
perljp perlko perlcn perltw
- •
- The documentation for the POSIX-BC platform is called "BS2000",
to avoid confusion with the Perl POSIX module.
- •
- The documentation for the WinCE platform is called perlce (README.ce in
the source code kit), to avoid confusion with the perlwin32 documentation
on 8.3-restricted filesystems.
- •
- 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. [561]
- •
- sort() is also fully reentrant, in the sense that the sort function
can itself call sort(). This did not work reliably in previous
releases. [561]
- •
- 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 "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
1 comes first is hard to know, since one 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, 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 $N doesn't just double the quicksort time, it
quadruples it. Quicksort has a worst case run time that can grow
like N**2, so-called quadratic behaviour, and it can happen on
patterns that may well arise in normal use. You won't notice this for
small arrays, but you will notice it with larger arrays, and you
may not live long enough for the sort to complete on arrays of a million
elements. So the 5.8 quicksort scrambles large arrays before sorting them,
as a statistical defence against quadratic behaviour. But that means if
you sort the same large array twice, ties may be broken in different ways.
Because of the unpredictability of tie-breaking order, and the quadratic
worst-case behaviour, quicksort was almost replaced completely with
a stable mergesort. Stable means that ties are broken to preserve
the original order of appearance in the input array. So
sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9);
will yield (4,3,1,1,5,9), guaranteed. The even and odd numbers appear in the
output in the same order they appeared in the input. Mergesort has worst
case O(N log N) behaviour, the best value attainable. And, ironically,
this mergesort does particularly well where quicksort goes quadratic:
mergesort sorts (1..$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 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 stable subpragma forces stable behaviour, regardless
of algorithm. The _quicksort and _mergesort subpragmas are
heavy-handed ways to select the underlying implementation. The leading
"_" 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.
- •
- 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.
- •
- unshift() should now be noticeably faster.
Installation and Configuration Improvements¶
Generic Improvements¶
- •
- INSTALL now explains how you can configure Perl to use 64-bit integers
even on non-64-bit platforms.
- •
- 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.
- •
- 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 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.
- •
- 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.
- •
- Since Perl 5.8 is not binary-compatible with previous releases of Perl,
Configure no longer suggests including the 5.005 modules in @INC.
- •
- Configure "-S" can now run non-interactively. [561]
- •
- Configure support for pdp11-style memory models has been removed due to
obsolescence. [561]
- •
- configure.gnu now works with options with whitespace in them.
- •
- installperl now outputs everything to STDERR.
- •
- 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.
- •
- 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.)
- •
- In AFS installations, one can configure the root of the AFS to be
somewhere else than the default /afs by using the Configure
parameter "-Dafsroot=/some/where/else".
- •
- APPLLIB_EXP, a lesser-known 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.
- •
- The version of Berkeley DB used when the Perl (and, presumably, the
DB_File extension) was built is now available as
@Config{qw(db_version_major db_version_minor db_version_patch)} from Perl
and as "DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG
DB_VERSION_PATCH_CFG" from C.
- •
- Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM has
been documented in INSTALL.
- •
- 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.
- •
- In addition to config.over, a new override file, config.arch, is
available. This file is supposed to be used by hints file writers for
architecture-wide changes (as opposed to config.over which is for
site-wide changes).
- •
- If your file system supports symbolic links, you can build Perl outside of
the source directory by
mkdir perl/build/directory
cd perl/build/directory
sh /path/to/perl/source/Configure -Dmksymlinks ...
This will create in 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 perl/build/directory. [561]
- •
- For Perl developers, several new make targets for profiling and debugging
have been added; see perlhack.
- •
- Use of the gprof tool to profile Perl has been documented in
perlhack. There is a make target called "perl.gprof" for
generating a gprofiled Perl executable.
- •
- If you have GCC 3, there is a make target called "perl.gcov" for
creating a gcoved Perl executable for coverage analysis. See
perlhack.
- •
- If you are on IRIX or Tru64 platforms, new profiling/debugging options
have been added; see perlhack for more information about pixie and Third
Degree.
- •
- Guidelines of how to construct minimal Perl installations have been added
to INSTALL.
- •
- The Thread extension is now not built at all under ithreads
("Configure -Duseithreads") because it wouldn't work anyway (the
Thread extension requires being Configured with
"-Duse5005threads").
Note that the 5.005 threads are unsupported and deprecated: if you
have code written for the old threads you should migrate it to the
new ithreads model.
- •
- The Gconvert macro ($Config{d_Gconvert}) used by perl for stringifying
floating-point numbers is now more picky about using sprintf %.*g rules
for the conversion. Some platforms that used to use gcvt may now resort to
the slower sprintf.
- •
- The obsolete method of making a special (e.g., debugging) flavor of perl
by saying
make LIBPERL=libperld.a
has been removed. Use -DDEBUGGING instead.
For the list of platforms known to support Perl, see "Supported
Platforms" in perlport.
- •
- AIX dynamic loading should be now better supported.
- •
- AIX should now work better with gcc, threads, and 64-bitness. Also the
long doubles support in AIX should be better now. See perlaix.
- •
- AtheOS ( http://www.atheos.cx/ ) is a new platform.
- •
- BeOS has been reclaimed.
- •
- The DG/UX platform now supports 5.005-style threads. See perldgux.
- •
- The DYNIX/ptx platform (also known as dynixptx) is supported at or near
osvers 4.5.2.
- •
- 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 perlos390, perlbs2000 (for POSIX-BC), and
perlvmesa for more information. ( Note: support for VM/ESA was
removed in Perl v5.18.0. The relevant information was in
README.vmesa)
- •
- 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. [561]
- •
- Mac OS Classic is now supported in the mainstream source package (MacPerl
has of course been available since perl 5.004 but now the source code
bases of standard Perl and MacPerl have been synchronised) [561]
- •
- Mac OS X (or Darwin) should now be able to build Perl even on HFS+
filesystems. (The case-insensitivity used to confuse the Perl build
process.)
- •
- NCR MP-RAS is now supported. [561]
- •
- All the NetBSD specific patches (except for the installation specific
ones) have been merged back to the main distribution.
- •
- NetWare from Novell is now supported. See perlnetware.
- •
- NonStop-UX is now supported. [561]
- •
- NEC SUPER-UX is now supported.
- •
- All the OpenBSD specific patches (except for the installation specific
ones) have been merged back to the main distribution.
- •
- Perl has been tested with the GNU pth userlevel thread package (
http://www.gnu.org/software/pth/pth.html ). All thread tests of Perl now
work, but not without adding some yield()s to the tests, so while
pth (and other userlevel thread implementations) can be considered to be
"working" with Perl ithreads, keep in mind the possible
non-preemptability of the underlying thread implementation.
- •
- Stratus VOS is now supported using Perl's native build method (Configure).
This is the recommended method to build Perl on VOS. The older methods,
which build miniperl, are still available. See perlvos. [561+]
- •
- The Amdahl UTS Unix mainframe platform is now supported. [561]
- •
- WinCE is now supported. See perlce.
- •
- z/OS (formerly known as OS/390, formerly known as MVS OE) now has support
for dynamic loading. This is not selected by default, however, you must
specify -Dusedl in the arguments of Configure. [561]
Selected Bug Fixes¶
Numerous memory leaks and uninitialized memory accesses have been hunted down.
Most importantly, anonymous subs used to leak quite a bit. [561]
- •
- The autouse pragma didn't work for Multi::Part::Function::Names.
- •
- caller() could cause core dumps in certain situations. Carp was
sometimes affected by this problem. In particular, caller() now
returns a subroutine name of "(unknown)" for subroutines that
have been removed from the symbol table.
- •
- chop(@list) in list context returned the characters chopped in reverse
order. This has been reversed to be in the right order. [561]
- •
- 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. [561]
- •
- 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's 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.
- •
- Several debugger fixes: exit code now reflects the script exit code,
condition "0" now treated correctly, the "d" command
now checks line number, $. no longer gets corrupted, and all debugger
output now goes correctly to the socket if RemotePort is set. [561]
- •
- The debugger (perl5db.pl) has been modified to present a more consistent
commands interface, via (CommandSet=580). perl5db.t was also added to test
the changes, and as a placeholder for further tests.
See perldebug.
- •
- The debugger has a new "dumpDepth" option to control the maximum
depth to which nested structures are dumped. The "x" command has
been extended so that "x N EXPR" dumps out the value of
EXPR to a depth of at most N levels.
- •
- The debugger can now show lexical variables if you have the CPAN module
PadWalker installed.
- •
- The order of DESTROYs has been made more predictable.
- •
- Perl 5.6.0 could emit spurious warnings about redefinition of
dl_error() when statically building extensions into perl. This has
been corrected. [561]
- •
- dprofpp -R didn't work.
- •
- *foo{FORMAT} now works.
- •
- Infinity is now recognized as a number.
- •
- UNIVERSAL::isa no longer caches methods incorrectly. (This broke the Tk
extension with 5.6.0.) [561]
- •
- 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.
- •
- Lexicals II: lexicals leaked at file scope into subroutines that were
declared before the lexicals.
- •
- Lexical warnings now propagating correctly between scopes and into
"eval "..."".
- •
- "use warnings qw(FATAL all)" did not work as intended. This has
been corrected. [561]
- •
- warnings::enabled() now reports the state of $^W correctly if the
caller isn't using lexical warnings. [561]
- •
- Line renumbering with eval and "#line" now works. [561]
- •
- Fixed numerous memory leaks, especially in eval "".
- •
- Localised tied variables no longer leak memory
use Tie::Hash;
tie my %tied_hash => 'Tie::StdHash';
...
# Used to leak memory every time local() was called;
# in a loop, this added up.
local($tied_hash{Foo}) = 1;
- •
- Localised hash elements (and %ENV) are correctly unlocalised to not exist,
if they didn't before they were localised.
use Tie::Hash;
tie my %tied_hash => 'Tie::StdHash';
...
# Nothing has set the FOO element so far
{ local $tied_hash{FOO} = 'Bar' }
# This used to print, but not now.
print "exists!\n" if exists $tied_hash{FOO};
As a side effect of this fix, tied hash interfaces must define the
EXISTS and DELETE methods.
- •
- mkdir() now ignores trailing slashes in the directory name, as
mandated by POSIX.
- •
- Some versions of glibc have a broken modfl(). This affects builds
with "-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.
- •
- Modulus of unsigned numbers now works (4063328477 % 65535 used to return
27406, instead of 27047). [561]
- •
- 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.
[561]
- •
- Numeric conversions did not recognize changes in the string value properly
in certain circumstances. [561]
- •
- Attributes (such as :shared) didn't work with our().
- •
- our() variables will not cause bogus "Variable will not stay
shared" warnings. [561]
- •
- "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. [561]
- •
- pack "Z" now correctly terminates the string with
"\0".
- •
- Fix password routines which in some shadow password platforms (e.g. HP-UX)
caused getpwent() to return every other entry.
- •
- The PERL5OPT environment variable (for passing command line arguments to
Perl) didn't work for more than a single group of options. [561]
- •
- PERL5OPT with embedded spaces didn't work.
- •
- printf() no longer resets the numeric locale to "C".
- •
- "qw(a\\b)" now parses correctly as 'a\\b': that is, as three
characters, not four. [561]
- •
- pos() did not return the correct value within s///ge in earlier
versions. This is now handled correctly. [561]
- •
- Printing quads (64-bit integers) with printf/sprintf now works without the
q L ll prefixes (assuming you are on a quad-capable platform).
- •
- Regular expressions on references and overloaded scalars now work.
[561+]
- •
- Right-hand side magic (GMAGIC) could in many cases such as string
concatenation be invoked too many times.
- •
- scalar() now forces scalar context even when used in void
context.
- •
- SOCKS support is now much more robust.
- •
- 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. [561]
- •
- Changed the POSIX character class "[[:space:]]" to include the
(very rarely used) vertical tab character. Added a new POSIX-ish character
class "[[:blank:]]" which stands for horizontal whitespace
(currently, the space and the tab).
- •
- 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. [561]
- •
- Some cases of inconsistent taint propagation (such as within hash values)
have been fixed.
- •
- The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds of
simple pattern matches. These are now handled better. [561]
- •
- Regular expression debug output (whether through "use re
'debug'" or via "-Dr") now looks better. [561]
- •
- Multi-line matches like ""a\nxb\n" =~ /(?!\A)x/m" were
flawed. The bug has been fixed. [561]
- •
- Use of $& could trigger a core dump under some situations. This is now
avoided. [561]
- •
- The regular expression captured submatches ($1, $2, ...) are now more
consistently unset if the match fails, instead of leaving false data lying
around in them. [561]
- •
- readline() on files opened in "slurp" mode could return
an extra "" (blank line) at the end in certain situations. This
has been corrected. [561]
- •
- Autovivification of symbolic references of special variables described in
perlvar (as in "${$num}") was accidentally disabled. This works
again now. [561]
- •
- Sys::Syslog ignored the "LOG_AUTH" constant.
- •
- $AUTOLOAD, sort(), lock(), and spawning subprocesses in
multiple threads simultaneously are now thread-safe.
- •
- Tie::Array's SPLICE method was broken.
- •
- Allow a read-only string on the left-hand side of a non-modifying
tr///.
- •
- If "STDERR" is tied, warnings caused by "warn" and
"die" now correctly pass to it.
- •
- Several Unicode fixes.
- •
- BOMs (byte order marks) at the beginning of Perl files (scripts, modules)
should now be transparently skipped. UTF-16 and UCS-2 encoded Perl files
should now be read correctly.
- •
- The character tables have been updated to Unicode 3.2.0.
- •
- 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.)
- •
- Generating illegal Unicode code points such as U+FFFE, or the UTF-16
surrogates, now also generates an optional warning.
- •
- "IsAlnum", "IsAlpha", and "IsWord" now match
titlecase.
- •
- Concatenation with the "." operator or via variable
interpolation, "eq", "substr", "reverse",
"quotemeta", the "x" operator, substitution with
"s///", single-quoted UTF-8, should now work.
- •
- The "tr///" operator now works. Note that the
"tr///CU" functionality has been removed (but see pack('U0',
...)).
- •
- "eval "v200"" now works.
- •
- Perl 5.6.0 parsed m/\x{ab}/ incorrectly, leading to spurious warnings.
This has been corrected. [561]
- •
- Zero entries were missing from the Unicode classes such as
"IsDigit".
- •
- Large unsigned numbers (those above 2**31) could sometimes lose their
unsignedness, causing bogus results in arithmetic operations. [561]
- •
- 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.
- •
- BSDI 4.*
Perl now works on post-4.0 BSD/OSes.
- •
- All BSDs
Setting $0 now works (as much as possible; see perlvar for details).
- •
- Cygwin
Numerous updates; currently synchronised with Cygwin 1.3.10.
- •
- Previously DYNIX/ptx had problems in its Configure probe for non-blocking
I/O.
- •
- EPOC
EPOC now better supported. See README.epoc. [561]
- •
- FreeBSD 3.*
Perl now works on post-3.0 FreeBSDs.
- •
- HP-UX
README.hpux updated; "Configure -Duse64bitall" now works; now uses
HP-UX malloc instead of Perl malloc.
- •
- IRIX
Numerous compilation flag and hint enhancements; accidental mixing of 32-bit
and 64-bit libraries (a doomed attempt) made much harder.
- •
- Linux
- •
- Long doubles should now work (see INSTALL). [561]
- •
- Linux previously had problems related to sockaddrlen when using
accept(), recvfrom() (in Perl: recv()),
getpeername(), and getsockname().
- •
- Mac OS Classic
Compilation of the standard Perl distribution in Mac OS 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.
- •
- MPE/iX
MPE/iX update after Perl 5.6.0. See README.mpeix. [561]
- •
- NetBSD/threads: try installing the GNU pth (should be in the packages
collection, or http://www.gnu.org/software/pth/), and Configure with
-Duseithreads.
- •
- NetBSD/sparc
Perl now works on NetBSD/sparc.
- •
- OS/2
Now works with usethreads (see INSTALL). [561]
- •
- Solaris
64-bitness using the Sun Workshop compiler now works.
- •
- Stratus VOS
The native build method requires at least VOS Release 14.5.0 and GNU C++/GNU
Tools 2.0.1 or later. The Perl pack function now maps overflowed values to
+infinity and underflowed values to -infinity.
- •
- Tru64 (aka Digital UNIX, aka DEC OSF/1)
The operating system version letter now recorded in $Config{osvers}. Allow
compiling with gcc (previously explicitly forbidden). Compiling with gcc
still not recommended because buggy code results, even with gcc
2.95.2.
- •
- Unicos
Fixed various alignment problems that lead into core dumps either during
build or later; no longer dies on math errors at runtime; now using full
quad integers (64 bits), previously was using only 46 bit integers for
speed.
- •
- VMS
See "Socket Extension Dynamic in VMS" and "IEEE-format
Floating Point Default on OpenVMS Alpha" for important changes not
otherwise listed here.
chdir() now works better despite a CRT bug; now works with
MULTIPLICITY (see INSTALL); now works with Perl's malloc.
The tainting of %ENV elements via "keys" or "values" was
previously unimplemented. It now works as documented.
The "waitpid" emulation has been improved. The worst bug (now
fixed) was that a pid of -1 would cause a wildcard search of all processes
on the system.
POSIX-style signals are now emulated much better on VMS versions prior to
7.0.
The "system" function and backticks operator have improved
functionality and better error handling. [561]
File access tests now use current process privileges rather than the user's
default privileges, which could sometimes result in a mismatch between
reported access and actual access. This improvement is only available on
VMS v6.0 and later.
There is a new "kill" implementation based on
"sys$sigprc" that allows older VMS systems (pre-7.0) to use
"kill" to send signals rather than simply force exit. This
implementation also allows later systems to call "kill" from
within a signal handler.
Iterative logical name translations are now limited to 10 iterations in
imitation of SHOW LOGICAL and other OpenVMS facilities.
- •
- Windows
- •
- Signal handling now works better than it used to. It is now implemented
using a Windows message loop, and is therefore less prone to random
crashes.
- •
- fork() emulation is now more robust, but still continues to have a
few esoteric bugs and caveats. See perlfork for details. [561+]
- •
- A failed (pseudo)fork now returns undef and sets errno to EAGAIN.
[561]
- •
- The following modules now work on Windows:
ExtUtils::Embed [561]
IO::Pipe
IO::Poll
Net::Ping
- •
- IO::File::new_tmpfile() is no longer limited to 32767 invocations
per-process.
- •
- Better chdir() return value for a non-existent directory.
- •
- Compiling perl using the 64-bit Platform SDK tools is now supported.
- •
- The Win32::SetChildShowWindow() builtin can be used to control the
visibility of windows created by child processes. See Win32 for
details.
- •
- Non-blocking waits for child processes (or pseudo-processes) are supported
via "waitpid($pid, &POSIX::WNOHANG)".
- •
- The behavior of system() with multiple arguments has been
rationalized. Each unquoted argument will be automatically quoted to
protect whitespace, and any existing whitespace in the arguments will be
preserved. This improves the portability of system(@args) by avoiding the
need for Windows "cmd" shell specific quoting in perl programs.
Note that this means that some scripts that may have relied on earlier buggy
behavior may no longer work correctly. For example,
"system("nmake /nologo", @args)" will now attempt to
run the file "nmake /nologo" and will fail when such a file
isn't found. On the other hand, perl will now execute code such as
"system("c:/Program Files/MyApp/foo.exe", @args)"
correctly.
- •
- The perl header files no longer suppress common warnings from the
Microsoft Visual C++ compiler. This means that additional warnings may now
show up when compiling XS code.
- •
- 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++). [561]
- •
- Duping socket handles with open(F, ">&MYSOCK") now works
under Windows 9x. [561]
- •
- Current directory entries in %ENV are now correctly propagated to child
processes. [561]
- •
- New %ENV entries now propagate to subprocesses. [561]
- •
- Win32::GetCwd() correctly returns C:\ instead of C: when at the
drive root. Other bugs in chdir() and Cwd::cwd() have also
been fixed. [561]
- •
- The makefiles now default to the features enabled in ActiveState
ActivePerl (a popular Win32 binary distribution). [561]
- •
- HTML files will now be installed in c:\perl\html instead of
c:\perl\lib\pod\html
- •
- REG_EXPAND_SZ keys are now allowed in registry settings used by perl.
[561]
- •
- Can now send() from all threads, not just the first one. [561]
- •
- ExtUtils::MakeMaker now uses $ENV{LIB} to search for libraries. [561]
- •
- Less stack reserved per thread so that more threads can run concurrently.
(Still 16M per thread.) [561]
- •
- "File::Spec->tmpdir()" now prefers C:/temp over /tmp (works
better when perl is running as service).
- •
- Better UNC path handling under ithreads. [561]
- •
- wait(), waitpid(), and backticks now return the correct exit
status under Windows 9x. [561]
- •
- A socket handle leak in accept() has been fixed. [561]
New or Changed Diagnostics¶
Please see perldiag for more details.
- •
- Ambiguous range in the transliteration operator (like a-z-9) now gives a
warning.
- •
- chdir("") and chdir(undef) now give a deprecation warning
because they cause a possible unintentional chdir to the home directory.
Say chdir() if you really mean that.
- •
- Two new debugging options have been added: if you have compiled your Perl
with debugging, you can use the -DT [561] and -DR options to trace
tokenising and to add reference counts to displaying variables,
respectively.
- •
- The lexical warnings category "deprecated" is no longer a
sub-category of the "syntax" category. It is now a top-level
category in its own right.
- •
- Unadorned dump() will now give a warning suggesting to use explicit
CORE::dump() if that's what really is meant.
- •
- The "Unrecognized escape" warning has been extended to include
"\8", "\9", and "\_". There is no need to
escape any of the "\w" characters.
- •
- 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
"<-- HERE" marker.
- •
- Various I/O (and socket) functions like binmode(), close(),
and so forth now more consistently warn if they are used illogically
either on a yet unopened or on an already closed filehandle (or
socket).
- •
- Using lstat() on a filehandle now gives a warning. (It's a
non-sensical thing to do.)
- •
- The "-M" and "-m" options now warn if you didn't
supply the module name.
- •
- If you in "use" specify a required minimum version, modules
matching the name and but not defining a $VERSION will cause a fatal
failure.
- •
- Using negative offset for vec() in lvalue context is now a warnable
offense.
- •
- Odd number of arguments to overload::constant now elicits a warning.
- •
- Odd number of elements in anonymous hash now elicits a warning.
- •
- The various "opened only for", "on closed",
"never opened" warnings drop the "main::" prefix for
filehandles in the "main" package, for example "STDIN"
instead of "main::STDIN".
- •
- Subroutine prototypes are now checked more carefully, you may get warnings
for example if you have used non-prototype characters.
- •
- If an attempt to use a (non-blessed) reference as an array index is made,
a warning is given.
- •
- "push @a;" and "unshift @a;" (with no values to push
or unshift) now give a warning. This may be a problem for generated and
eval'ed code.
- •
- If you try to "pack" in perlfunc a number less than 0 or larger
than 255 using the "C" format you will get an optional warning.
Similarly for the "c" format and a number less than -128 or more
than 127.
- •
- pack "P" format now demands an explicit size.
- •
- unpack "w" now warns of unterminated compressed integers.
- •
- Warnings relating to the use of PerlIO have been added.
- •
- Certain regex modifiers such as "(?o)" make sense only if
applied to the entire regex. You will get an optional warning if you try
to do otherwise.
- •
- Variable length lookbehind has not yet been implemented, trying to use it
will tell that.
- •
- Using arrays or hashes as references (e.g. "%foo->{bar}" has
been deprecated for a while. Now you will get an optional warning.
- •
- Warnings relating to the use of the new restricted hashes feature have
been added.
- •
- Self-ties of arrays and hashes are not supported and fatal errors will
happen even at an attempt to do so.
- •
- Using "sort" in scalar context now issues an optional warning.
This didn't do anything useful, as the sort was not performed.
- •
- Using the /g modifier in split() is meaningless and will cause a
warning.
- •
- Using splice() past the end of an array now causes a warning.
- •
- Malformed Unicode encodings (UTF-8 and UTF-16) cause a lot of warnings, as
does trying to use UTF-16 surrogates (which are unimplemented).
- •
- Trying to use Unicode characters on an I/O stream without marking the
stream's encoding (using open() or binmode()) will cause
"Wide character" warnings.
- •
- Use of v-strings in use/require causes a (backward) portability
warning.
- •
- Warnings relating to the use interpreter threads and their shared data
have been added.
Changed Internals¶
- •
- PerlIO is now the default.
- •
- perlapi.pod (a companion to perlguts) now attempts to document the
internal API.
- •
- You can now build a really minimal perl called microperl. Building
microperl does not require even running Configure; "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.
- •
- 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 perlapi.
- •
- Made possible to propagate customised exceptions via
croak()ing.
- •
- Now xsubs can have attributes just like subs. (Well, at least the built-in
attributes.)
- •
- dTHR and djSP have been obsoleted; the former removed (because it's a
no-op) and the latter replaced with dSP.
- •
- PERL_OBJECT has been completely removed.
- •
- The MAGIC constants (e.g. 'P') have been macrofied (e.g.
"PERL_MAGIC_TIED") for better source code readability and
maintainability.
- •
- The regex compiler now maintains a structure that identifies nodes in the
compiled bytecode with the corresponding syntactic features of the
original regex expression. The information is attached to the new
"offsets" member of the "struct regexp". See
perldebguts for more complete information.
- •
- The C code has been made much more "gcc -Wall" clean. Some
warning messages still remain in some platforms, so if you are compiling
with gcc you may see some warnings about dubious practices. The warnings
are being worked on.
- •
- perly.c, sv.c, and sv.h have now been extensively
commented.
- •
- Documentation on how to use the Perl source repository has been added to
Porting/repository.pod.
- •
- There are now several profiling make targets.
Security Vulnerability Closed [561]¶
(This change was already made in 5.7.0 but bears repeating here.) (5.7.0 came
out before 5.6.1: the development branch 5.7 released earlier than the
maintenance branch 5.6)
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/ ).
New Tests¶
Several new tests have been added, especially for the
lib and
ext
subsections. There are now about 69 000 individual tests (spread over about
700 test scripts), in the regression suite (5.6.1 has about 11 700 tests, in
258 test scripts) The exact numbers depend on the platform and Perl
configuration used. Many of the new tests are of course 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. On a really fast machine you can hope to
finish the suite in about 6-8 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.)
Known Problems¶
The Compiler Suite Is Still Very Experimental¶
The compiler suite is slowly getting better but it continues to be highly
experimental. Use in production environments is discouraged.
Localising Tied Arrays and Hashes Is Broken¶
local %tied_array;
doesn't work as one would expect: the old value is restored incorrectly. This
will be changed in a future release, but we don't know yet what the new
semantics will exactly be. In any case, the change will break existing code
that relies on the current (ill-defined) semantics, so just avoid doing this
in general.
Building Extensions Can Fail Because Of Largefiles¶
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 they may 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 to) link together at all binaries with different
ideas about file offsets; all this is platform-dependent.
Modifying $_ Inside for(..)¶
for (1..5) { $_++ }
works without complaint. It shouldn't. (You should be able to modify only lvalue
elements inside the loops.) You can see the correct behaviour by replacing the
1..5 with 1, 2, 3, 4, 5.
mod_perl 1.26 Doesn't Build With Threaded Perl¶
Use mod_perl 1.27 or higher.
lib/ftmp-security tests warn 'system possibly insecure'¶
Don't panic. Read the 'make test' section of INSTALL instead.
libwww-perl (LWP) fails base/date #51¶
Use libwww-perl 5.65 or later.
PDL failing some tests¶
Use PDL 2.3.4 or later.
Perl_get_sv¶
You may get errors like 'Undefined symbol "Perl_get_sv"' or
"can't resolve symbol 'Perl_get_sv'", or the symbol may be
"Perl_sv_2pv". This probably means that you are trying to use an
older shared Perl library (or extensions linked with such) with Perl 5.8.0
executable. Perl used to have such a subroutine, but that is no more the case.
Check your shared library path, and any shared Perl libraries in those
directories.
Sometimes this problem may also indicate a partial Perl 5.8.0 installation, see
"Mac OS X dyld undefined symbols" for an example and how to deal
with it.
Self-tying Problems¶
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 forbidden for now (you will
get a fatal error even from an attempt).
A change to self-tying of globs has caused them to be recursively referenced
(see: "Two-Phased Garbage Collection" in perlobj). You will now need
an explicit untie to destroy a self-tied glob. This behaviour may be fixed at
a later date.
Self-tying of scalars and IO thingies works.
ext/threads/t/libc¶
If this test fails, it indicates that your libc (C library) is not threadsafe.
This particular test stress tests the
localtime() call to find out
whether it is threadsafe. See perlthrtut for more information.
Failure of Thread (5.005-style) tests¶
Note that support for 5.005-style threading is deprecated,
experimental and practically unsupported. In 5.10, it is expected to
be removed. You should migrate your code to ithreads.
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.
../ext/B/t/xref.t 255 65280 14 12 85.71% 3-14
../ext/List/Util/t/first.t 255 65280 7 4 57.14% 2 5-7
../lib/English.t 2 512 54 2 3.70% 2-3
../lib/FileCache.t 5 1 20.00% 5
../lib/Filter/Simple/t/data.t 6 3 50.00% 1-3
../lib/Filter/Simple/t/filter_only. 9 3 33.33% 1-2 5
../lib/Math/BigInt/t/bare_mbf.t 1627 4 0.25% 8 11 1626-1627
../lib/Math/BigInt/t/bigfltpm.t 1629 4 0.25% 10 13 1628-
1629
../lib/Math/BigInt/t/sub_mbf.t 1633 4 0.24% 8 11 1632-1633
../lib/Math/BigInt/t/with_sub.t 1628 4 0.25% 9 12 1627-1628
../lib/Tie/File/t/31_autodefer.t 255 65280 65 32 49.23% 34-65
../lib/autouse.t 10 1 10.00% 4
op/flip.t 15 1 6.67% 15
These failures are unlikely to get fixed as 5.005-style threads are considered
fundamentally broken. (Basically what happens is that competing threads can
corrupt shared global state, one good example being regular expression
engine's state.)
Timing problems¶
The following tests may fail intermittently because of timing problems, for
example if the system is heavily loaded.
t/op/alarm.t
ext/Time/HiRes/HiRes.t
lib/Benchmark.t
lib/Memoize/t/expmod_t.t
lib/Memoize/t/speed.t
In case of failure please try running them manually, for example
./perl -Ilib ext/Time/HiRes/HiRes.t
Tied/Magical Array/Hash Elements Do Not Autovivify¶
For normal arrays "$foo = \$bar[1]" will assign "undef" to
$bar[1] (assuming that it didn't exist before), but for tied/magical arrays
and hashes such autovivification does not happen because there is currently no
way to catch the reference creation. The same problem affects slicing over
non-existent indices/keys of a tied/magical array/hash.
Unicode in package/class and subroutine names does not work¶
One can have Unicode in identifier names, but not in package/class or subroutine
names. While some limited functionality towards this does exist as of Perl
5.8.0, that is more accidental than designed; use of Unicode for the said
purposes is unsupported.
One reason of this unfinishedness is its (currently) inherent unportability:
since both package names and subroutine names may need to be mapped to file
and directory names, the Unicode capability of the filesystem becomes
important-- and there unfortunately aren't portable answers.
AIX¶
- •
- If using the AIX native make command, instead of just "make"
issue "make all". In some setups the former has been known to
spuriously also try to run "make install". Alternatively, you
may want to use GNU make.
- •
- In AIX 4.2, Perl extensions that use C++ functions that use statics may
have problems in that the statics are not getting initialized. In newer
AIX releases, this has been solved by linking Perl with the libC_r
library, but unfortunately in AIX 4.2 the said library has an obscure bug
where the various functions related to time (such as time() and
gettimeofday()) return broken values, and therefore in AIX 4.2 Perl
is not linked against libC_r.
- •
- 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
a few random tests failing when run as part of "make test", 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.
See README.aix.
- •
- If building threaded Perl, you may get compilation warning from pp_sys.c:
"pp_sys.c", line 4651.39: 1506-280 (W) Function argument assignment between types "unsigned char*" and "const void*" is not allowed.
This is harmless; it is caused by the getnetbyaddr() and
getnetbyaddr_r() having slightly different types for their first
argument.
Alpha systems with old gccs fail several tests¶
If you see op/pack, op/pat, op/regexp, or ext/Storable tests failing in a
Linux/alpha or *BSD/Alpha, it's probably time to upgrade your gcc. gccs prior
to 2.95.3 are definitely not good enough, and gcc 3.1 may be even better.
(RedHat Linux/alpha with gcc 3.1 reported no problems, as did Linux 2.4.18
with gcc 2.95.4.) (In Tru64, it is preferable to use the bundled C compiler.)
AmigaOS¶
Perl 5.8.0 doesn't build in AmigaOS. It broke at some point during the ithreads
work and we could not find Amiga experts to unbreak the problems. Perl 5.6.1
still works for AmigaOS (as does the 5.7.2 development release).
BeOS¶
The following tests fail on 5.8.0 Perl in BeOS Personal 5.03:
t/op/lfs............................FAILED at test 17
t/op/magic..........................FAILED at test 24
ext/Fcntl/t/syslfs..................FAILED at test 17
ext/File/Glob/t/basic...............FAILED at test 3
ext/POSIX/t/sigaction...............FAILED at test 13
ext/POSIX/t/waitpid.................FAILED at test 1
(
Note: more information was available in
README.beos until
support for BeOS was removed in Perl v5.18.0)
Cygwin "unable to remap"¶
For example when building the Tk extension for Cygwin, you may get an error
message saying "unable to remap". This is known problem with Cygwin,
and a workaround is detailed in here:
http://sources.redhat.com/ml/cygwin/2001-12/msg00894.html
Cygwin ndbm tests fail on FAT¶
One can build but not install (or test the build of) the NDBM_File on FAT
filesystems. Installation (or build) on NTFS works fine. If one attempts the
test on a FAT install (or build) the following failures are expected:
../ext/NDBM_File/ndbm.t 13 3328 71 59 83.10% 1-2 4 16-71
../ext/ODBM_File/odbm.t 255 65280 ?? ?? % ??
../lib/AnyDBM_File.t 2 512 12 2 16.67% 1 4
../lib/Memoize/t/errors.t 0 139 11 5 45.45% 7-11
../lib/Memoize/t/tie_ndbm.t 13 3328 4 4 100.00% 1-4
run/fresh_perl.t 97 1 1.03% 91
NDBM_File fails and ODBM_File just coredumps.
If you intend to run only on FAT (or if using AnyDBM_File on FAT), run Configure
with the -Ui_ndbm and -Ui_dbm options to prevent NDBM_File and ODBM_File being
built.
DJGPP Failures¶
t/op/stat............................FAILED at test 29
lib/File/Find/t/find.................FAILED at test 1
lib/File/Find/t/taint................FAILED at test 1
lib/h2xs.............................FAILED at test 15
lib/Pod/t/eol........................FAILED at test 1
lib/Test/Harness/t/strap-analyze.....FAILED at test 8
lib/Test/Harness/t/test-harness......FAILED at test 23
lib/Test/Simple/t/exit...............FAILED at test 1
The above failures are known as of 5.8.0 with native builds with long filenames,
but there are a few more if running under dosemu because of limitations (and
maybe bugs) of dosemu:
t/comp/cpp...........................FAILED at test 3
t/op/inccode.........................(crash)
and a few lib/ExtUtils tests, and several hundred Encode/t/Aliases.t failures
that work fine with long filenames. So you really might prefer native builds
and long filenames.
FreeBSD built with ithreads coredumps reading large directories¶
This is a known bug in FreeBSD 4.5's
readdir_r(), it has been fixed in
FreeBSD 4.6 (see perlfreebsd (README.freebsd)).
FreeBSD Failing locale Test 117 For ISO 8859-15 Locales¶
The ISO 8859-15 locales may fail the locale test 117 in FreeBSD. This is caused
by the characters \xFF (y with diaeresis) and \xBE (Y with diaeresis) not
behaving correctly when being matched case-insensitively. Apparently this
problem has been fixed in the latest FreeBSD releases. (
http://www.freebsd.org/cgi/query-pr.cgi?pr=34308 )
IRIX fails ext/List/Util/t/shuffle.t or Digest::MD5¶
IRIX with MIPSpro 7.3.1.2m or 7.3.1.3m compiler may fail the List::Util test
ext/List/Util/t/shuffle.t by dumping core. This seems to be a compiler error
since if compiled with gcc no core dump ensues, and no failures have been seen
on the said test on any other platform.
Similarly, building the Digest::MD5 extension has been known to fail with
"*** Termination code 139 (bu21)".
The cure is to drop optimization level (Configure -Doptimize=-O2).
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.
Linux with glibc 2.2.5 fails t/op/int subtest #6 with -Duse64bitint¶
This is a known bug in the glibc 2.2.5 with long long integers. (
http://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=65612 )
Linux With Sfio Fails op/misc Test 48¶
No known fix.
Mac OS X¶
Please remember to set your environment variable LC_ALL to "C" (setenv
LC_ALL C) before running "make test" to avoid a lot of warnings
about the broken locales of Mac OS X.
The following tests are known to fail in Mac OS X 10.1.5 because of buggy (old)
implementations of Berkeley DB included in Mac OS X:
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
If you are building on a UFS partition, you will also probably see t/op/stat.t
subtest #9 fail. This is caused by Darwin's UFS not supporting inode change
time.
Also the ext/POSIX/t/posix.t subtest #10 fails but it is skipped for now because
the failure is Apple's fault, not Perl's (blocked signals are lost).
If you Configure with ithreads, ext/threads/t/libc.t will fail. Again, this is
not Perl's fault-- the libc of Mac OS X is not threadsafe (in this particular
test, the
localtime() call is found to be threadunsafe.)
Mac OS X dyld undefined symbols¶
If after installing Perl 5.8.0 you are getting warnings about missing symbols,
for example
dyld: perl Undefined symbols
_perl_sv_2pv
_perl_get_sv
you probably have an old pre-Perl-5.8.0 installation (or parts of one) in
/Library/Perl (the undefined symbols used to exist in pre-5.8.0 Perls). It
seems that for some reason "make install" doesn't always completely
overwrite the files in /Library/Perl. You can move the old Perl shared library
out of the way like this:
cd /Library/Perl/darwin/CORE
mv libperl.dylib libperlold.dylib
and then reissue "make install". Note that the above of course is
extremely disruptive for anything using the /usr/local/bin/perl. If that
doesn't help, you may have to try removing all the .bundle files from beneath
/Library/Perl, and again "make install"-ing.
OS/2 Test Failures¶
The following tests are known to fail on OS/2 (for clarity only the failures are
shown, not the full error messages):
../lib/ExtUtils/t/Mkbootstrap.t 1 256 18 1 5.56% 8
../lib/ExtUtils/t/Packlist.t 1 256 34 1 2.94% 17
../lib/ExtUtils/t/basic.t 1 256 17 1 5.88% 14
lib/os2_process.t 2 512 227 2 0.88% 174 209
lib/os2_process_kid.t 227 2 0.88% 174 209
lib/rx_cmprt.t 255 65280 18 3 16.67% 16-18
op/sprintf tests 91, 129, and 130¶
The op/sprintf tests 91, 129, and 130 are known to fail on some platforms.
Examples include any platform using sfio, and Compaq/Tandem's NonStop-UX.
Test 91 is known to fail on QNX6 (nto), because "sprintf '%e',0"
incorrectly produces 0.000000e+0 instead of 0.000000e+00.
For tests 129 and 130, the failing platforms do not comply with the ANSI C
Standard: lines 19ff on page 134 of ANSI X3.159 1989, to be exact. (They
produce something other than "1" and "-1" when formatting
0.6 and -0.6 using the printf format "%.0f"; most often, they
produce "0" and "-0".)
SCO¶
The socketpair tests are known to be unhappy in SCO 3.2v5.0.4:
ext/Socket/socketpair.t...............FAILED tests 15-45
Solaris 2.5¶
In case you are still using Solaris 2.5 (aka SunOS 5.5), you may experience
failures (the test core dumping) in lib/locale.t. The suggested cure is to
upgrade your Solaris.
Solaris x86 Fails Tests With -Duse64bitint¶
The following tests are known to fail in Solaris x86 with Perl configured to use
64 bit integers:
ext/Data/Dumper/t/dumper.............FAILED at test 268
ext/Devel/Peek/Peek..................FAILED at test 7
SUPER-UX (NEC SX)¶
The following tests are known to fail on SUPER-UX:
op/64bitint...........................FAILED tests 29-30, 32-33, 35-36
op/arith..............................FAILED tests 128-130
op/pack...............................FAILED tests 25-5625
op/pow................................
op/taint..............................# msgsnd failed
../ext/IO/lib/IO/t/io_poll............FAILED tests 3-4
../ext/IPC/SysV/ipcsysv...............FAILED tests 2, 5-6
../ext/IPC/SysV/t/msg.................FAILED tests 2, 4-6
../ext/Socket/socketpair..............FAILED tests 12
../lib/IPC/SysV.......................FAILED tests 2, 5-6
../lib/warnings.......................FAILED tests 115-116, 118-119
The op/pack failure ("Cannot compress negative numbers at op/pack.t line
126") is serious but as of yet unsolved. It points at some problems with
the signedness handling of the C compiler, as do the 64bitint, arith, and pow
failures. Most of the rest point at problems with SysV IPC.
Term::ReadKey not working on Win32¶
Use Term::ReadKey 2.20 or later.
UNICOS/mk¶
- •
- During Configure, the test
Guessing which symbols your C compiler and preprocessor define...
will probably fail with error messages like
CC-20 cc: ERROR File = try.c, Line = 3
The identifier "bad" is undefined.
bad switch yylook 79bad switch yylook 79bad switch yylook 79bad switch yylook 79#ifdef A29K
^
CC-65 cc: ERROR File = try.c, Line = 3
A semicolon is expected at this point.
This is caused by a bug in the awk utility of UNICOS/mk. You can ignore the
error, but it does cause a slight problem: you cannot fully benefit from
the h2ph utility (see h2ph) that can be used to convert C headers to Perl
libraries, mainly used to be able to access from Perl the constants
defined using C preprocessor, cpp. Because of the above error, parts of
the converted headers will be invisible. Luckily, these days the need for
h2ph is rare.
- •
- If building Perl with interpreter threads (ithreads), the
getgrent(), getgrnam(), and getgrgid() functions
cannot return the list of the group members due to a bug in the
multithreaded support of UNICOS/mk. What this means is that in list
context the functions will return only three values, not four.
UTS¶
There are a few known test failures. (
Note: the relevant information was
available in
README.uts until support for UTS was removed in Perl
v5.18.0)
VOS (Stratus)¶
When Perl is built using the native build process on VOS Release 14.5.0 and GNU
C++/GNU Tools 2.0.1, all attempted tests either pass or result in TODO
(ignored) failures.
VMS¶
There should be no reported test failures with a default configuration, though
there are a number of tests marked TODO that point to areas needing further
debugging and/or porting work.
Win32¶
In multi-CPU boxes, there are some problems with the I/O buffering: some output
may appear twice.
XML::Parser not working¶
Use XML::Parser 2.31 or later.
z/OS (OS/390)¶
z/OS has rather many test failures but the situation is actually much better
than it was in 5.6.0; it's just that so many new modules and tests have been
added.
Failed Test Stat Wstat Total Fail Failed List of Failed
---------------------------------------------------------------------------
../ext/Data/Dumper/t/dumper.t 357 8 2.24% 311 314 325 327
331 333 337 339
../ext/IO/lib/IO/t/io_unix.t 5 4 80.00% 2-5
../ext/Storable/t/downgrade.t 12 3072 169 12 7.10% 14-15 46-47 78-79
110-111 150 161
../lib/ExtUtils/t/Constant.t 121 30976 48 48 100.00% 1-48
../lib/ExtUtils/t/Embed.t 9 9 100.00% 1-9
op/pat.t 922 7 0.76% 665 776 785 832-
834 845
op/sprintf.t 224 3 1.34% 98 100 136
op/tr.t 97 5 5.15% 63 71-74
uni/fold.t 780 6 0.77% 61 169 196 661
710-711
The failures in dumper.t and downgrade.t are problems in the tests, those in
io_unix and sprintf are problems in the USS (UDP sockets and printf formats).
The pat, tr, and fold failures are genuine Perl problems caused by EBCDIC (and
in the pat and fold cases, combining that with Unicode). The Constant and
Embed are probably problems in the tests (since they test Perl's ability to
build extensions, and that seems to be working reasonably well.)
Unicode Support on EBCDIC Still Spotty¶
Though mostly working, Unicode support still has problem spots on EBCDIC
platforms. One such known spot are the "\p{}" and "\P{}"
regular expression constructs for code points less than 256: the
"pP" are testing for Unicode code points, not knowing about EBCDIC.
Seen In Perl 5.7 But Gone Now¶
"Time::Piece" (previously known as "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.
Perl 5.8 unfortunately does not build anymore on AmigaOS; this broke
accidentally at some point. Since there are not that many Amiga developers
available, we could not get this fixed and tested in time for 5.8.0. Perl
5.6.1 still works for AmigaOS (as does the 5.7.2 development release).
The "PerlIO::Scalar" and "PerlIO::Via" (capitalised) were
renamed as "PerlIO::scalar" and "PerlIO::via" (all
lowercase) just before 5.8.0. The main rationale was to have all core PerlIO
layers to have all lowercase names. The "plugins" are named as
usual, for example "PerlIO::via::QuotedPrint".
The "threads::shared::queue" and
"threads::shared::semaphore" were renamed as
"Thread::Queue" and "Thread::Semaphore" just before 5.8.0.
The main rationale was to have thread modules to obey normal naming,
"Thread::" (the "threads" and "threads::shared"
themselves are more pragma-like, they affect compile-time, so they stay
lowercase).
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/
, the Perl Home Page.
If you believe you have an unreported bug, please run the
perlbug program
included with your release. Be sure to trim your bug down to a tiny but
sufficient test case. Your bug report, along with the output of "perl
-V", will be sent off to perlbug@perl.org to be analysed by the Perl
porting team.
SEE ALSO¶
The
Changes file for exhaustive details on what changed.
The
INSTALL file for how to build Perl.
The
README file for general stuff.
The
Artistic and
Copying files for copyright information.
HISTORY¶
Written by Jarkko Hietaniemi <
jhi@iki.fi>.