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diff --git a/upstream/debian-unstable/man1/perl58delta.1 b/upstream/debian-unstable/man1/perl58delta.1 new file mode 100644 index 00000000..5ea560a9 --- /dev/null +++ b/upstream/debian-unstable/man1/perl58delta.1 @@ -0,0 +1,2906 @@ +.\" -*- mode: troff; coding: utf-8 -*- +.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43) +.\" +.\" Standard preamble: +.\" ======================================================================== +.de Sp \" Vertical space (when we can't use .PP) +.if t .sp .5v +.if n .sp +.. +.de Vb \" Begin verbatim text +.ft CW +.nf +.ne \\$1 +.. +.de Ve \" End verbatim text +.ft R +.fi +.. +.\" \*(C` and \*(C' are quotes in nroff, nothing in troff, for use with C<>. +.ie n \{\ +. ds C` "" +. ds C' "" +'br\} +.el\{\ +. ds C` +. ds C' +'br\} +.\" +.\" Escape single quotes in literal strings from groff's Unicode transform. +.ie \n(.g .ds Aq \(aq +.el .ds Aq ' +.\" +.\" If the F register is >0, we'll generate index entries on stderr for +.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index +.\" entries marked with X<> in POD. Of course, you'll have to process the +.\" output yourself in some meaningful fashion. +.\" +.\" Avoid warning from groff about undefined register 'F'. +.de IX +.. +.nr rF 0 +.if \n(.g .if rF .nr rF 1 +.if (\n(rF:(\n(.g==0)) \{\ +. if \nF \{\ +. de IX +. tm Index:\\$1\t\\n%\t"\\$2" +.. +. if !\nF==2 \{\ +. nr % 0 +. nr F 2 +. \} +. \} +.\} +.rr rF +.\" ======================================================================== +.\" +.IX Title "PERL58DELTA 1" +.TH PERL58DELTA 1 2024-01-12 "perl v5.38.2" "Perl Programmers Reference Guide" +.\" For nroff, turn off justification. Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH NAME +perl58delta \- what is new for perl v5.8.0 +.SH DESCRIPTION +.IX Header "DESCRIPTION" +This document describes differences between the 5.6.0 release and +the 5.8.0 release. +.PP +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). +.PP +Changes that were integrated into the 5.6.1 release are marked \f(CW\*(C`[561]\*(C'\fR. +Many of these changes have been further developed since 5.6.1 was released, +those are marked \f(CW\*(C`[561+]\*(C'\fR. +.PP +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. +.SH "Highlights In 5.8.0" +.IX Header "Highlights In 5.8.0" +.IP \(bu 4 +Better Unicode support +.IP \(bu 4 +New IO Implementation +.IP \(bu 4 +New Thread Implementation +.IP \(bu 4 +Better Numeric Accuracy +.IP \(bu 4 +Safe Signals +.IP \(bu 4 +Many New Modules +.IP \(bu 4 +More Extensive Regression Testing +.SH "Incompatible Changes" +.IX Header "Incompatible Changes" +.SS "Binary Incompatibility" +.IX Subsection "Binary Incompatibility" +\&\fBPerl 5.8 is not binary compatible with earlier releases of Perl.\fR +.PP +\&\fBYou have to recompile your XS modules.\fR +.PP +(Pure Perl modules should continue to work.) +.PP +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. +.PP +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. +.PP +Depending on your platform, there are also other reasons why +we decided to break binary compatibility, please read on. +.SS "64\-bit platforms and malloc" +.IX Subsection "64-bit platforms and malloc" +If your pointers are 64 bits wide, the Perl malloc is no longer being +used because it does not work well with 8\-byte pointers. Also, +usually the system mallocs on such platforms are much better optimized +for such large memory models than the Perl malloc. Some memory-hungry +Perl applications like the PDL don't work well with Perl's malloc. +Finally, other applications than Perl (such as mod_perl) tend to prefer +the system malloc. Such platforms include Alpha and 64\-bit HPPA, +MIPS, PPC, and Sparc. +.SS "AIX Dynaloading" +.IX Subsection "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. +.ie n .SS "Attributes for ""my"" variables now handled at run-time" +.el .SS "Attributes for \f(CWmy\fP variables now handled at run-time" +.IX Subsection "Attributes for my variables now handled at run-time" +The \f(CW\*(C`my EXPR : ATTRS\*(C'\fR syntax now applies variable attributes at +run-time. (Subroutine and \f(CW\*(C`our\*(C'\fR variables still get attributes applied +at compile-time.) See attributes for additional details. In particular, +however, this allows variable attributes to be useful for \f(CW\*(C`tie\*(C'\fR 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). +.SS "Socket Extension Dynamic in VMS" +.IX Subsection "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. +.SS "IEEE-format Floating Point Default on OpenVMS Alpha" +.IX Subsection "IEEE-format Floating Point Default on OpenVMS Alpha" +Perl now uses IEEE format (T_FLOAT) as the default internal floating +point format on OpenVMS Alpha, potentially breaking binary compatibility +with external libraries or existing data. G_FLOAT is still available as +a configuration option. The default on VAX (D_FLOAT) has not changed. +.ie n .SS "New Unicode Semantics (no more ""use utf8"", almost)" +.el .SS "New Unicode Semantics (no more \f(CWuse utf8\fP, almost)" +.IX Subsection "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. +.PP +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.) +.PP +See perluniintro for the explanation of the current model, +and utf8 for the current use of the utf8 pragma. +.SS "New Unicode Properties" +.IX Subsection "New Unicode Properties" +Unicode \fIscripts\fR are now supported. Scripts are similar to (and superior +to) Unicode \fIblocks\fR. 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. +.PP +In general, scripts are more inclusive, but not universally so. For +example, while the script \f(CW\*(C`Latin\*(C'\fR 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 \f(CW\*(C`Latin\*(C'\fR). +.PP +A number of other properties are now supported, including \f(CW\*(C`\ep{L&}\*(C'\fR, +\&\f(CW\*(C`\ep{Any}\*(C'\fR \f(CW\*(C`\ep{Assigned}\*(C'\fR, \f(CW\*(C`\ep{Unassigned}\*(C'\fR, \f(CW\*(C`\ep{Blank}\*(C'\fR [561] and +\&\f(CW\*(C`\ep{SpacePerl}\*(C'\fR [561] (along with their \f(CW\*(C`\eP{...}\*(C'\fR versions, of course). +See perlunicode for details, and more additions. +.PP +The \f(CW\*(C`In\*(C'\fR or \f(CW\*(C`Is\*(C'\fR prefix to names used with the \f(CW\*(C`\ep{...}\*(C'\fR and \f(CW\*(C`\eP{...}\*(C'\fR +are now almost always optional. The only exception is that a \f(CW\*(C`In\*(C'\fR prefix +is required to signify a Unicode block when a block name conflicts with a +script name. For example, \f(CW\*(C`\ep{Tibetan}\*(C'\fR refers to the script, while +\&\f(CW\*(C`\ep{InTibetan}\*(C'\fR refers to the block. When there is no name conflict, you +can omit the \f(CW\*(C`In\*(C'\fR from the block name (e.g. \f(CW\*(C`\ep{BraillePatterns}\*(C'\fR), but +to be safe, it's probably best to always use the \f(CW\*(C`In\*(C'\fR). +.SS "REF(...) Instead Of SCALAR(...)" +.IX Subsection "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 \fBref()\fR. +.SS "pack/unpack D/F recycled" +.IX Subsection "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.) +.SS "\fBglob()\fP now returns filenames in alphabetical order" +.IX Subsection "glob() now returns filenames in alphabetical order" +The list of filenames from \fBglob()\fR (or <...>) is now by default sorted +alphabetically to be csh-compliant (which is what happened before +in most Unix platforms). (\fBbsd_glob()\fR does still sort platform +natively, ASCII or EBCDIC, unless GLOB_ALPHASORT is specified.) [561] +.SS Deprecations +.IX Subsection "Deprecations" +.IP \(bu 4 +The semantics of bless(REF, REF) were unclear and until someone proves +it to make some sense, it is forbidden. +.IP \(bu 4 +The obsolete chat2 library that should never have been allowed +to escape the laboratory has been decommissioned. +.IP \(bu 4 +Using chdir("") or chdir(undef) instead of explicit \fBchdir()\fR is +doubtful. A failure (think chdir(\fBsome_function()\fR) can lead into +unintended \fBchdir()\fR to the home directory, therefore this behaviour +is deprecated. +.IP \(bu 4 +The builtin \fBdump()\fR function has probably outlived most of its +usefulness. The core-dumping functionality will remain in future +available as an explicit call to \f(CWCORE::dump()\fR, but in future +releases the behaviour of an unqualified \f(CWdump()\fR call may change. +.IP \(bu 4 +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. +.IP \(bu 4 +The (bogus) escape sequences \e8 and \e9 now give an optional warning +("Unrecognized escape passed through"). There is no need to \e\-escape +any \f(CW\*(C`\ew\*(C'\fR character. +.IP \(bu 4 +The *glob{FILEHANDLE} is deprecated, use *glob{IO} instead. +.IP \(bu 4 +The \f(CW\*(C`package;\*(C'\fR syntax (\f(CW\*(C`package\*(C'\fR 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, \f(CW\*(C`use strict;\*(C'\fR instead. +.IP \(bu 4 +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. +.IP \(bu 4 +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. +.IP \(bu 4 +Previous versions of perl and some readings of some sections of Camel +III implied that the \f(CW\*(C`:raw\*(C'\fR "discipline" was the inverse of \f(CW\*(C`:crlf\*(C'\fR. +Turning off "clrfness" is no longer enough to make a stream truly +binary. So the PerlIO \f(CW\*(C`:raw\*(C'\fR 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 \f(CW\*(C`:raw\*(C'\fR \- will now turn off both +CRLF and UTF\-8 translation and remove other layers (e.g. :\fBencoding()\fR) +which would modify byte stream. +.IP \(bu 4 +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 \f(CW\*(C`fields\*(C'\fR pragma interface will remain +available. The \fIrestricted hashes\fR 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. +.IP \(bu 4 +The syntaxes \f(CW\*(C`@a\->[...]\*(C'\fR and \f(CW\*(C`%h\->{...}\*(C'\fR have now been deprecated. +.IP \(bu 4 +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. +.IP \(bu 4 +The 5.005 threads model (module \f(CW\*(C`Thread\*(C'\fR) 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). +.IP \(bu 4 +The long deprecated uppercase aliases for the string comparison +operators (EQ, NE, LT, LE, GE, GT) have now been removed. +.IP \(bu 4 +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] +.IP \(bu 4 +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. +.IP \(bu 4 +The \f(CW\*(C`exec LIST\*(C'\fR and \f(CW\*(C`system LIST\*(C'\fR operations now produce warnings on +tainted data and in some future release they will produce fatal errors. +.IP \(bu 4 +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". +.SH "Core Enhancements" +.IX Header "Core Enhancements" +.SS "Unicode Overhaul" +.IX Subsection "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. +.IP \(bu 4 +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.) +.IP \(bu 4 +For developers interested in enhancing Perl's Unicode capabilities: +almost all the UCD files are included with the Perl distribution in +the \fIlib/unicore\fR subdirectory. The most notable omission, for space +considerations, is the Unihan database. +.IP \(bu 4 +The properties \ep{Blank} and \ep{SpacePerl} have been added. "Blank" is like +C \fBisblank()\fR, that is, it contains only "horizontal whitespace" (the space +character is, the newline isn't), and the "SpacePerl" is the Unicode +equivalent of \f(CW\*(C`\es\*(C'\fR (\ep{Space} isn't, since that includes the vertical +tabulator character, whereas \f(CW\*(C`\es\*(C'\fR doesn't.) +.Sp +See "New Unicode Properties" earlier in this document for additional +information on changes with Unicode properties. +.SS "PerlIO is Now The Default" +.IX Subsection "PerlIO is Now The Default" +.IP \(bu 4 +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: +.Sp +.Vb 1 +\& open($fh,\*(Aq>:crlf :utf8\*(Aq, $path) || ... +.Ve +.Sp +or on already opened handles via extended \f(CW\*(C`binmode\*(C'\fR: +.Sp +.Vb 1 +\& binmode($fh,\*(Aq:encoding(iso\-8859\-7)\*(Aq); +.Ve +.Sp +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 <=> "\en" translation as on Win32, +but available on any platform). A mmap layer may be available if +platform supports it (mostly Unixes). +.Sp +Layers to be applied by default may be specified via the 'open' pragma. +.Sp +See "Installation and Configuration Improvements" for the effects +of PerlIO on your architecture name. +.IP \(bu 4 +If your platform supports \fBfork()\fR, you can use the list form of \f(CW\*(C`open\*(C'\fR +for pipes. For example: +.Sp +.Vb 1 +\& open KID_PS, "\-|", "ps", "aux" or die $!; +.Ve +.Sp +forks the \fBps\fR\|(1) command (without spawning a shell, as there are more +than three arguments to \fBopen()\fR), and reads its standard output via the +\&\f(CW\*(C`KID_PS\*(C'\fR filehandle. See perlipc. +.IP \(bu 4 +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" : +.Sp +.Vb 1 +\& open($fh,">:utf8","Uni.txt"); +.Ve +.Sp +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/reports/tr16/ for more information. +In future releases this naming may change. See perluniintro +for more information about UTF\-8. +.IP \(bu 4 +If your environment variables (LC_ALL, LC_CTYPE, LANG) look like you +want to use UTF\-8 (any of the variables match \f(CW\*(C`/utf\-?8/i\*(C'\fR), 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.) +.Sp +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. +.Sp +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 \fBopen()\fR or \fBbinmode()\fR +with \f(CW\*(C`:bytes\*(C'\fR (see "open" in perlfunc and "binmode" in perlfunc), or you +can just use \f(CWbinmode(FH)\fR (nice for pre\-5.8.0 backward compatibility). +.IP \(bu 4 +File handles can translate character encodings from/to Perl's internal +Unicode form on read/write via the ":\fBencoding()\fR" layer. +.IP \(bu 4 +File handles can be opened to "in memory" files held in Perl scalars via: +.Sp +.Vb 1 +\& open($fh,\*(Aq>\*(Aq, \e$variable) || ... +.Ve +.IP \(bu 4 +Anonymous temporary files are available without need to +\&'use FileHandle' or other module via +.Sp +.Vb 1 +\& open($fh,"+>", undef) || ... +.Ve +.Sp +That is a literal undef, not an undefined value. +.SS ithreads +.IX Subsection "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. +.PP +As a part of the ithreads implementation Perl will also use +any necessary and detectable reentrant libc interfaces. +.SS "Restricted Hashes" +.IX Subsection "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. +.SS "Safe Signals" +.IX Subsection "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). +.PP +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 \fBsort()\fR) 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. +.SS "Understanding of Numbers" +.IX Subsection "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 \f(CWstrtoul()\fR +and \f(CWatof()\fR seem to have bugs, Perl tries to work around their +deficiencies. This results hopefully in more accurate numbers. +.PP +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.) +.SS "Arrays now always interpolate into double-quoted strings [561]" +.IX Subsection "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 +.PP +.Vb 1 +\& Literal @example now requires backslash +.Ve +.PP +In versions 5.004_01 through 5.6.0, the error was +.PP +.Vb 1 +\& In string, @example now must be written as \e@example +.Ve +.PP +The idea here was to get people into the habit of writing +\&\f(CW"fred\e@example.com"\fR when they wanted a literal \f(CW\*(C`@\*(C'\fR sign, just as +they have always written \f(CW"Give me back my \e$5"\fR when they wanted a +literal \f(CW\*(C`$\*(C'\fR sign. +.PP +Starting with 5.6.1, when Perl now sees an \f(CW\*(C`@\*(C'\fR sign in a +double-quoted string, it \fIalways\fR 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: +.PP +.Vb 1 +\& Possible unintended interpolation of @example in string +.Ve +.PP +This warns you that \f(CW"fred@example.com"\fR is going to turn into +\&\f(CW\*(C`fred.com\*(C'\fR if you don't backslash the \f(CW\*(C`@\*(C'\fR. +See http://perl.plover.com/at\-error.html for more details +about the history here. +.SS "Miscellaneous Changes" +.IX Subsection "Miscellaneous Changes" +.IP \(bu 4 +AUTOLOAD is now lvaluable, meaning that you can add the :lvalue attribute +to AUTOLOAD subroutines and you can assign to the AUTOLOAD return value. +.IP \(bu 4 +The \f(CW$Config\fR{byteorder} (and corresponding BYTEORDER in config.h) was +previously wrong in platforms if sizeof(long) was 4, but sizeof(IV) +was 8. The byteorder was only sizeof(long) bytes long (1234 or 4321), +but now it is correctly sizeof(IV) bytes long, (12345678 or 87654321). +(This problem didn't affect Windows platforms.) +.Sp +Also, \f(CW$Config\fR{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. +.IP \(bu 4 +\&\f(CW\*(C`perl \-d:Module=arg,arg,arg\*(C'\fR now works (previously one couldn't pass +in multiple arguments.) +.IP \(bu 4 +\&\f(CW\*(C`do\*(C'\fR followed by a bareword now ensures that this bareword isn't +a keyword (to avoid a bug where \f(CW\*(C`do q(foo.pl)\*(C'\fR tried to call a +subroutine called \f(CW\*(C`q\*(C'\fR). This means that for example instead of +\&\f(CW\*(C`do format()\*(C'\fR you must write \f(CW\*(C`do &format()\*(C'\fR. +.IP \(bu 4 +The builtin \fBdump()\fR now gives an optional warning +\&\f(CW\*(C`dump() better written as CORE::dump()\*(C'\fR, +meaning that by default \f(CWdump(...)\fR is resolved as the builtin +\&\fBdump()\fR which dumps core and aborts, not as (possibly) user-defined +\&\f(CW\*(C`sub dump\*(C'\fR. To call the latter, qualify the call as \f(CW&dump(...)\fR. +(The whole \fBdump()\fR feature is to considered deprecated, and possibly +removed/changed in future releases.) +.IP \(bu 4 +\&\fBchomp()\fR and \fBchop()\fR are now overridable. Note, however, that their +prototype (as given by \f(CWprototype("CORE::chomp")\fR is undefined, +because it cannot be expressed and therefore one cannot really write +replacements to override these builtins. +.IP \(bu 4 +END blocks are now run even if you exit/die in a BEGIN block. +Internally, the execution of END blocks is now controlled by +PL_exit_flags & PERL_EXIT_DESTRUCT_END. This enables the new +behaviour for Perl embedders. This will default in 5.10. See +perlembed. +.IP \(bu 4 +Formats now support zero-padded decimal fields. +.IP \(bu 4 +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". +.IP \(bu 4 +lstat(FILEHANDLE) now gives a warning because the operation makes no sense. +In future releases this may become a fatal error. +.IP \(bu 4 +Spurious syntax errors generated in certain situations, when \fBglob()\fR +caused File::Glob to be loaded for the first time, have been fixed. [561] +.IP \(bu 4 +Lvalue subroutines can now return \f(CW\*(C`undef\*(C'\fR in list context. However, +the lvalue subroutine feature still remains experimental. [561+] +.IP \(bu 4 +A lost warning "Can't declare ... dereference in my" has been +restored (Perl had it earlier but it became lost in later releases.) +.IP \(bu 4 +A new special regular expression variable has been introduced: +\&\f(CW$^N\fR, which contains the most-recently closed group (submatch). +.IP \(bu 4 +\&\f(CW\*(C`no Module;\*(C'\fR does not produce an error even if Module does not have an +\&\fBunimport()\fR method. This parallels the behavior of \f(CW\*(C`use\*(C'\fR vis-a-vis +\&\f(CW\*(C`import\*(C'\fR. [561] +.IP \(bu 4 +The numerical comparison operators return \f(CW\*(C`undef\*(C'\fR if either operand +is a NaN. Previously the behaviour was unspecified. +.IP \(bu 4 +\&\f(CW\*(C`our\*(C'\fR can now have an experimental optional attribute \f(CW\*(C`unique\*(C'\fR that +affects how global variables are shared among multiple interpreters, +see "our" in perlfunc. +.IP \(bu 4 +The following builtin functions are now overridable: \fBeach()\fR, \fBkeys()\fR, +\&\fBpop()\fR, \fBpush()\fR, \fBshift()\fR, \fBsplice()\fR, \fBunshift()\fR. [561] +.IP \(bu 4 +\&\f(CW\*(C`pack() / unpack()\*(C'\fR can now group template letters with \f(CW\*(C`()\*(C'\fR and then +apply repetition/count modifiers on the groups. +.IP \(bu 4 +\&\f(CW\*(C`pack() / unpack()\*(C'\fR can now process the Perl internal numeric types: +IVs, UVs, NVs\-\- and also long doubles, if supported by the platform. +The template letters are \f(CW\*(C`j\*(C'\fR, \f(CW\*(C`J\*(C'\fR, \f(CW\*(C`F\*(C'\fR, and \f(CW\*(C`D\*(C'\fR. +.IP \(bu 4 +\&\f(CW\*(C`pack(\*(AqU0a*\*(Aq, ...)\*(C'\fR can now be used to force a string to UTF\-8. +.IP \(bu 4 +my _\|_PACKAGE_\|_ \f(CW$obj\fR now works. [561] +.IP \(bu 4 +\&\fBPOSIX::sleep()\fR now returns the number of \fIunslept\fR seconds +(as the POSIX standard says), as opposed to \fBCORE::sleep()\fR which +returns the number of slept seconds. +.IP \(bu 4 +\&\fBprintf()\fR and \fBsprintf()\fR now support parameter reordering using the +\&\f(CW\*(C`%\ed+\e$\*(C'\fR and \f(CW\*(C`*\ed+\e$\*(C'\fR syntaxes. For example +.Sp +.Vb 1 +\& printf "%2\e$s %1\e$s\en", "foo", "bar"; +.Ve +.Sp +will print "bar foo\en". This feature helps in writing +internationalised software, and in general when the order +of the parameters can vary. +.IP \(bu 4 +The (\e&) prototype now works properly. [561] +.IP \(bu 4 +prototype(\e[$@%&]) is now available to implicitly create references +(useful for example if you want to emulate the \fBtie()\fR interface). +.IP \(bu 4 +A new command-line option, \f(CW\*(C`\-t\*(C'\fR is available. It is the +little brother of \f(CW\*(C`\-T\*(C'\fR: instead of dying on taint violations, +lexical warnings are given. \fBThis is only meant as a temporary +debugging aid while securing the code of old legacy applications. +This is not a substitute for \-T.\fR +.IP \(bu 4 +In other taint news, the \f(CW\*(C`exec LIST\*(C'\fR and \f(CW\*(C`system LIST\*(C'\fR have now been +considered too risky (think \f(CW\*(C`exec @ARGV\*(C'\fR: 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. +.IP \(bu 4 +Tied hash interfaces are now required to have the EXISTS and DELETE +methods (either own or inherited). +.IP \(bu 4 +If tr/// is just counting characters, it doesn't attempt to +modify its target. +.IP \(bu 4 +\&\fBuntie()\fR will now call an \fBUNTIE()\fR hook if it exists. See perltie +for details. [561] +.IP \(bu 4 +"utime" in perlfunc now supports \f(CW\*(C`utime undef, undef, @files\*(C'\fR to change the +file timestamps to the current time. +.IP \(bu 4 +The rules for allowing underscores (underbars) in numeric constants +have been relaxed and simplified: now you can have an underscore +simply \fBbetween digits\fR. +.IP \(bu 4 +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 \fI/proc/self/exe\fR on Linux, \fI/proc/curproc/file\fR on FreeBSD) +.IP \(bu 4 +A new variable, \f(CW\*(C`${^TAINT}\*(C'\fR, indicates whether taint mode is enabled. +.IP \(bu 4 +You can now override the \fBreadline()\fR builtin, and this overrides also +the <FILEHANDLE> angle bracket operator. +.IP \(bu 4 +The command-line options \-s and \-F are now recognized on the shebang +(#!) line. +.IP \(bu 4 +Use of the \f(CW\*(C`/c\*(C'\fR match modifier without an accompanying \f(CW\*(C`/g\*(C'\fR modifier +elicits a new warning: \f(CW\*(C`Use of /c modifier is meaningless without /g\*(C'\fR. +.Sp +Use of \f(CW\*(C`/c\*(C'\fR in substitutions, even with \f(CW\*(C`/g\*(C'\fR, elicits +\&\f(CW\*(C`Use of /c modifier is meaningless in s///\*(C'\fR. +.Sp +Use of \f(CW\*(C`/g\*(C'\fR with \f(CW\*(C`split\*(C'\fR elicits \f(CW\*(C`Use of /g modifier is meaningless +in split\*(C'\fR. +.IP \(bu 4 +Support for the \f(CW\*(C`CLONE\*(C'\fR 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 \f(CW\*(C`CLONE\*(C'\fR you +can do whatever you need to do, like for example handle the cloning of +non-Perl data, if necessary. \f(CW\*(C`CLONE\*(C'\fR 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. +.Sp +See perlmod +.SH "Modules and Pragmata" +.IX Header "Modules and Pragmata" +.SS "New Modules and Pragmata" +.IX Subsection "New Modules and Pragmata" +.IP \(bu 4 +\&\f(CW\*(C`Attribute::Handlers\*(C'\fR, originally by Damian Conway and now maintained +by Arthur Bergman, allows a class to define attribute handlers. +.Sp +.Vb 3 +\& package MyPack; +\& use Attribute::Handlers; +\& sub Wolf :ATTR(SCALAR) { print "howl!\en" } +\& +\& # later, in some package using or inheriting from MyPack... +\& +\& my MyPack $Fluffy : Wolf; # the attribute handler Wolf will be called +.Ve +.Sp +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. +.IP \(bu 4 +\&\f(CW\*(C`B::Concise\*(C'\fR, 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+] +.IP \(bu 4 +The new bignum, bigint, and bigrat pragmas, by Tels, implement +transparent bignum support (using the Math::BigInt, Math::BigFloat, +and Math::BigRat backends). +.IP \(bu 4 +\&\f(CW\*(C`Class::ISA\*(C'\fR, by Sean Burke, is a module for reporting the search +path for a class's ISA tree. See Class::ISA. +.IP \(bu 4 +\&\f(CW\*(C`Cwd\*(C'\fR 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. +.IP \(bu 4 +\&\f(CW\*(C`Devel::PPPort\*(C'\fR, originally by Kenneth Albanowski and now +maintained by Paul Marquess, has been added. It is primarily used +by \f(CW\*(C`h2xs\*(C'\fR to enhance portability of XS modules between different +versions of Perl. See Devel::PPPort. +.IP \(bu 4 +\&\f(CW\*(C`Digest\*(C'\fR, frontend module for calculating digests (checksums), from +Gisle Aas, has been added. See Digest. +.IP \(bu 4 +\&\f(CW\*(C`Digest::MD5\*(C'\fR for calculating MD5 digests (checksums) as defined in +RFC 1321, from Gisle Aas, has been added. See Digest::MD5. +.Sp +.Vb 1 +\& use Digest::MD5 \*(Aqmd5_hex\*(Aq; +\& +\& $digest = md5_hex("Thirsty Camel"); +\& +\& print $digest, "\en"; # 01d19d9d2045e005c3f1b80e8b164de1 +.Ve +.Sp +NOTE: the \f(CW\*(C`MD5\*(C'\fR backward compatibility module is deliberately not +included since its further use is discouraged. +.Sp +See also PerlIO::via::QuotedPrint. +.IP \(bu 4 +\&\f(CW\*(C`Encode\*(C'\fR, 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. +.Sp +Any encoding supported by Encode module is also available to the +":\fBencoding()\fR" layer if PerlIO is used. +.IP \(bu 4 +\&\f(CW\*(C`Hash::Util\*(C'\fR is the interface to the new \fIrestricted hashes\fR +feature. (Implemented by Jeffrey Friedl, Nick Ing-Simmons, and +Michael Schwern.) See Hash::Util. +.IP \(bu 4 +\&\f(CW\*(C`I18N::Langinfo\*(C'\fR can be used to query locale information. +See I18N::Langinfo. +.IP \(bu 4 +\&\f(CW\*(C`I18N::LangTags\*(C'\fR, by Sean Burke, has functions for dealing with +RFC3066\-style language tags. See I18N::LangTags. +.IP \(bu 4 +\&\f(CW\*(C`ExtUtils::Constant\*(C'\fR, by Nicholas Clark, is a new tool for extension +writers for generating XS code to import C header constants. +See ExtUtils::Constant. +.IP \(bu 4 +\&\f(CW\*(C`Filter::Simple\*(C'\fR, by Damian Conway, is an easy-to-use frontend to +Filter::Util::Call. See Filter::Simple. +.Sp +.Vb 1 +\& # in MyFilter.pm: +\& +\& package MyFilter; +\& +\& use Filter::Simple sub { +\& while (my ($from, $to) = splice @_, 0, 2) { +\& s/$from/$to/g; +\& } +\& }; +\& +\& 1; +\& +\& # in user\*(Aqs code: +\& +\& use MyFilter qr/red/ => \*(Aqgreen\*(Aq; +\& +\& print "red\en"; # this code is filtered, will print "green\en" +\& print "bored\en"; # this code is filtered, will print "bogreen\en" +\& +\& no MyFilter; +\& +\& print "red\en"; # this code is not filtered, will print "red\en" +.Ve +.IP \(bu 4 +\&\f(CW\*(C`File::Temp\*(C'\fR, by Tim Jenness, allows one to create temporary files +and directories in an easy, portable, and secure way. See File::Temp. +[561+] +.IP \(bu 4 +\&\f(CW\*(C`Filter::Util::Call\*(C'\fR, by Paul Marquess, provides you with the +framework to write \fIsource filters\fR in Perl. For most uses, the +frontend Filter::Simple is to be preferred. See Filter::Util::Call. +.IP \(bu 4 +\&\f(CW\*(C`if\*(C'\fR, by Ilya Zakharevich, is a new pragma for conditional inclusion +of modules. +.IP \(bu 4 +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. +.Sp +Perl installation leaves libnet unconfigured; use \fIlibnetcfg\fR +to configure it. +.IP \(bu 4 +\&\f(CW\*(C`List::Util\*(C'\fR, by Graham Barr, is a selection of general-utility +list subroutines, such as \fBsum()\fR, \fBmin()\fR, \fBfirst()\fR, and \fBshuffle()\fR. +See List::Util. +.IP \(bu 4 +\&\f(CW\*(C`Locale::Constants\*(C'\fR, \f(CW\*(C`Locale::Country\*(C'\fR, \f(CW\*(C`Locale::Currency\*(C'\fR +\&\f(CW\*(C`Locale::Language\*(C'\fR, 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. +.Sp +.Vb 1 +\& use Locale::Country; +\& +\& $country = code2country(\*(Aqjp\*(Aq); # $country gets \*(AqJapan\*(Aq +\& $code = country2code(\*(AqNorway\*(Aq); # $code gets \*(Aqno\*(Aq +.Ve +.Sp +See Locale::Constants, Locale::Country, Locale::Currency, +and Locale::Language. +.IP \(bu 4 +\&\f(CW\*(C`Locale::Maketext\*(C'\fR, 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. +.IP \(bu 4 +\&\f(CW\*(C`Math::BigRat\*(C'\fR for big rational numbers, to accompany Math::BigInt and +Math::BigFloat, from Tels. See Math::BigRat. +.IP \(bu 4 +\&\f(CW\*(C`Memoize\*(C'\fR can make your functions faster by trading space for time, +from Mark-Jason Dominus. See Memoize. +.IP \(bu 4 +\&\f(CW\*(C`MIME::Base64\*(C'\fR, by Gisle Aas, allows you to encode data in base64, +as defined in RFC 2045 \- \fIMIME (Multipurpose Internet Mail +Extensions)\fR. +.Sp +.Vb 1 +\& use MIME::Base64; +\& +\& $encoded = encode_base64(\*(AqAladdin:open sesame\*(Aq); +\& $decoded = decode_base64($encoded); +\& +\& print $encoded, "\en"; # "QWxhZGRpbjpvcGVuIHNlc2FtZQ==" +.Ve +.Sp +See MIME::Base64. +.IP \(bu 4 +\&\f(CW\*(C`MIME::QuotedPrint\*(C'\fR, by Gisle Aas, allows you to encode data +in quoted-printable encoding, as defined in RFC 2045 \- \fIMIME +(Multipurpose Internet Mail Extensions)\fR. +.Sp +.Vb 1 +\& use MIME::QuotedPrint; +\& +\& $encoded = encode_qp("\exDE\exAD\exBE\exEF"); +\& $decoded = decode_qp($encoded); +\& +\& print $encoded, "\en"; # "=DE=AD=BE=EF\en" +\& print $decoded, "\en"; # "\exDE\exAD\exBE\exEF\en" +.Ve +.Sp +See also PerlIO::via::QuotedPrint. +.IP \(bu 4 +\&\f(CW\*(C`NEXT\*(C'\fR, by Damian Conway, is a pseudo-class for method redispatch. +See NEXT. +.IP \(bu 4 +\&\f(CW\*(C`open\*(C'\fR is a new pragma for setting the default I/O layers +for \fBopen()\fR. +.IP \(bu 4 +\&\f(CW\*(C`PerlIO::scalar\*(C'\fR, 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. +.IP \(bu 4 +\&\f(CW\*(C`PerlIO::via\*(C'\fR, by Nick Ing-Simmons, acts as a PerlIO layer and wraps +PerlIO layer functionality provided by a class (typically implemented +in Perl code). +.IP \(bu 4 +\&\f(CW\*(C`PerlIO::via::QuotedPrint\*(C'\fR, by Elizabeth Mattijsen, is an example +of a \f(CW\*(C`PerlIO::via\*(C'\fR class: +.Sp +.Vb 2 +\& use PerlIO::via::QuotedPrint; +\& open($fh,">:via(QuotedPrint)",$path); +.Ve +.Sp +This will automatically convert everything output to \f(CW$fh\fR to +Quoted-Printable. See PerlIO::via and PerlIO::via::QuotedPrint. +.IP \(bu 4 +\&\f(CW\*(C`Pod::ParseLink\*(C'\fR, by Russ Allbery, has been added, +to parse L<> links in pods as described in the new +perlpodspec. +.IP \(bu 4 +\&\f(CW\*(C`Pod::Text::Overstrike\*(C'\fR, by Joe Smith, has been added. +It converts POD data to formatted overstrike text. +See Pod::Text::Overstrike. [561+] +.IP \(bu 4 +\&\f(CW\*(C`Scalar::Util\*(C'\fR is a selection of general-utility scalar subroutines, +such as \fBblessed()\fR, \fBreftype()\fR, and \fBtainted()\fR. See Scalar::Util. +.IP \(bu 4 +\&\f(CW\*(C`sort\*(C'\fR is a new pragma for controlling the behaviour of \fBsort()\fR. +.IP \(bu 4 +\&\f(CW\*(C`Storable\*(C'\fR 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. +.IP \(bu 4 +\&\f(CW\*(C`Switch\*(C'\fR, by Damian Conway, has been added. Just by saying +.Sp +.Vb 1 +\& use Switch; +.Ve +.Sp +you have \f(CW\*(C`switch\*(C'\fR and \f(CW\*(C`case\*(C'\fR available in Perl. +.Sp +.Vb 1 +\& 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 /\ew+/ { print "pattern" } +\& case qr/\ew+/ { print "pattern" } +\& case (%hash) { print "entry in hash" } +\& case (\e%hash) { print "entry in hash" } +\& case (\e&sub) { print "arg to subroutine" } +\& else { print "previous case not true" } +\& } +.Ve +.Sp +See Switch. +.IP \(bu 4 +\&\f(CW\*(C`Test::More\*(C'\fR, by Michael Schwern, is yet another framework for writing +test scripts, more extensive than Test::Simple. See Test::More. +.IP \(bu 4 +\&\f(CW\*(C`Test::Simple\*(C'\fR, by Michael Schwern, has basic utilities for writing +tests. See Test::Simple. +.IP \(bu 4 +\&\f(CW\*(C`Text::Balanced\*(C'\fR, by Damian Conway, has been added, for extracting +delimited text sequences from strings. +.Sp +.Vb 1 +\& use Text::Balanced \*(Aqextract_delimited\*(Aq; +\& +\& ($a, $b) = extract_delimited("\*(Aqnever say never\*(Aq, he never said", "\*(Aq", \*(Aq\*(Aq); +.Ve +.Sp +\&\f(CW$a\fR will be "'never say never'", \f(CW$b\fR will be ', he never said'. +.Sp +In addition to \fBextract_delimited()\fR, there are also \fBextract_bracketed()\fR, +\&\fBextract_quotelike()\fR, \fBextract_codeblock()\fR, \fBextract_variable()\fR, +\&\fBextract_tagged()\fR, \fBextract_multiple()\fR, \fBgen_delimited_pat()\fR, and +\&\fBgen_extract_tagged()\fR. With these, you can implement rather advanced +parsing algorithms. See Text::Balanced. +.IP \(bu 4 +\&\f(CW\*(C`threads\*(C'\fR, 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 \f(CWfork()\fR emulation). See threads, +threads::shared, and perlthrtut. +.IP \(bu 4 +\&\f(CW\*(C`threads::shared\*(C'\fR, by Arthur Bergman, allows data sharing for +interpreter threads. See threads::shared. +.IP \(bu 4 +\&\f(CW\*(C`Tie::File\*(C'\fR, by Mark-Jason Dominus, associates a Perl array with the +lines of a file. See Tie::File. +.IP \(bu 4 +\&\f(CW\*(C`Tie::Memoize\*(C'\fR, by Ilya Zakharevich, provides on-demand loaded hashes. +See Tie::Memoize. +.IP \(bu 4 +\&\f(CW\*(C`Tie::RefHash::Nestable\*(C'\fR, by Edward Avis, allows storing hash +references (unlike the standard Tie::RefHash) The module is contained +within Tie::RefHash. See Tie::RefHash. +.IP \(bu 4 +\&\f(CW\*(C`Time::HiRes\*(C'\fR, by Douglas E. Wegscheid, provides high resolution +timing (ualarm, usleep, and gettimeofday). See Time::HiRes. +.IP \(bu 4 +\&\f(CW\*(C`Unicode::UCD\*(C'\fR offers a querying interface to the Unicode Character +Database. See Unicode::UCD. +.IP \(bu 4 +\&\f(CW\*(C`Unicode::Collate\*(C'\fR, by SADAHIRO Tomoyuki, implements the UCA +(Unicode Collation Algorithm) for sorting Unicode strings. +See Unicode::Collate. +.IP \(bu 4 +\&\f(CW\*(C`Unicode::Normalize\*(C'\fR, by SADAHIRO Tomoyuki, implements the various +Unicode normalization forms. See Unicode::Normalize. +.IP \(bu 4 +\&\f(CW\*(C`XS::APItest\*(C'\fR, by Tim Jenness, is a test extension that exercises XS +APIs. Currently only \f(CWprintf()\fR is tested: how to output various +basic data types from XS. +.IP \(bu 4 +\&\f(CW\*(C`XS::Typemap\*(C'\fR, by Tim Jenness, is a test extension that exercises +XS typemaps. Nothing gets installed, but the code is worth studying +for extension writers. +.SS "Updated And Improved Modules and Pragmata" +.IX Subsection "Updated And Improved Modules and Pragmata" +.IP \(bu 4 +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. +.IP \(bu 4 +\&\fBattributes::reftype()\fR now works on tied arguments. +.IP \(bu 4 +AutoLoader can now be disabled with \f(CW\*(C`no AutoLoader;\*(C'\fR. +.IP \(bu 4 +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. +.IP \(bu 4 +Carp now has better interface documentation, and the \f(CW@CARP_NOT\fR +interface has been added to get optional control over where errors +are reported independently of \f(CW@ISA\fR, by Ben Tilly. +.IP \(bu 4 +Class::Struct can now define the classes in compile time. +.IP \(bu 4 +Class::Struct now assigns the array/hash element if the accessor +is called with an array/hash element as the \fBsole\fR argument. +.IP \(bu 4 +The return value of \fBCwd::fastcwd()\fR is now tainted. +.IP \(bu 4 +Data::Dumper now has an option to sort hashes. +.IP \(bu 4 +Data::Dumper now has an option to dump code references +using B::Deparse. +.IP \(bu 4 +DB_File now supports newer Berkeley DB versions, among +other improvements. +.IP \(bu 4 +Devel::Peek now has an interface for the Perl memory statistics +(this works only if you are using perl's malloc, and if you have +compiled with debugging). +.IP \(bu 4 +The English module can now be used without the infamous performance +hit by saying +.Sp +.Vb 1 +\& use English \*(Aq\-no_match_vars\*(Aq; +.Ve +.Sp +(Assuming, of course, that you don't need the troublesome variables +\&\f(CW\*(C`$\`\*(C'\fR, \f(CW$&\fR, or \f(CW\*(C`$\*(Aq\*(C'\fR.) Also, introduced \f(CW@LAST_MATCH_START\fR and +\&\f(CW@LAST_MATCH_END\fR English aliases for \f(CW\*(C`@\-\*(C'\fR and \f(CW\*(C`@+\*(C'\fR. +.IP \(bu 4 +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. +.IP \(bu 4 +The arguments of \fBWriteMakefile()\fR 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. +.IP \(bu 4 +ExtUtils::MakeMaker now uses File::Spec internally, which hopefully +leads to better portability. +.IP \(bu 4 +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. +.IP \(bu 4 +File::Find now \fBchdir()\fRs correctly when chasing symbolic links. [561] +.IP \(bu 4 +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. +.IP \(bu 4 +File::Find is now (again) reentrant. It also has been made +more portable. +.IP \(bu 4 +The warnings issued by File::Find now belong to their own category. +You can enable/disable them with \f(CW\*(C`use/no warnings \*(AqFile::Find\*(Aq;\*(C'\fR. +.IP \(bu 4 +\&\fBFile::Glob::glob()\fR has been renamed to \fBFile::Glob::bsd_glob()\fR +because the name clashes with the builtin \fBglob()\fR. The older +name is still available for compatibility, but is deprecated. [561] +.IP \(bu 4 +File::Glob now supports \f(CW\*(C`GLOB_LIMIT\*(C'\fR constant to limit the size of +the returned list of filenames. +.IP \(bu 4 +IPC::Open3 now allows the use of numeric file descriptors. +.IP \(bu 4 +IO::Socket now has an \fBatmark()\fR method, which returns true if the socket +is positioned at the out-of-band mark. The method is also exportable +as a \fBsockatmark()\fR function. +.IP \(bu 4 +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] +.IP \(bu 4 +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. +.IP \(bu 4 +IO::Socket::INET now supports a value of zero for \f(CW\*(C`LocalPort\*(C'\fR +(usually meaning that the operating system will make one up.) +.IP \(bu 4 +\&'use lib' now works identically to \f(CW@INC\fR. Removing directories +with 'no lib' now works. +.IP \(bu 4 +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. +.IP \(bu 4 +Math::Complex handles inf, NaN etc., better. +.IP \(bu 4 +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. +.Sp +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. +.IP \(bu 4 +\&\fBPOSIX::sigaction()\fR is now much more flexible and robust. +You can now install coderef handlers, 'DEFAULT', and 'IGNORE' +handlers, installing new handlers was not atomic. +.IP \(bu 4 +In Safe, \f(CW%INC\fR is now localised in a Safe compartment so that +use/require work. +.IP \(bu 4 +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. +.IP \(bu 4 +In Search::Dict one can now have a pre-processing hook for the +lines being searched. +.IP \(bu 4 +The Shell module now has an OO interface. +.IP \(bu 4 +In Sys::Syslog there is now a failover mechanism that will go +through alternative connection mechanisms until the message +is successfully logged. +.IP \(bu 4 +The Test module has been significantly enhanced. +.IP \(bu 4 +\&\fBTime::Local::timelocal()\fR does not handle fractional seconds anymore. +The rationale is that neither does \fBlocaltime()\fR, and \fBtimelocal()\fR and +\&\fBlocaltime()\fR are supposed to be inverses of each other. +.IP \(bu 4 +The vars pragma now supports declaring fully qualified variables. +(Something that \f(CWour()\fR does not and will not support.) +.IP \(bu 4 +The \f(CW\*(C`utf8::\*(C'\fR 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 \fBlength()\fR +has been implemented. +.SH "Utility Changes" +.IX Header "Utility Changes" +.IP \(bu 4 +Emacs perl mode (emacs/cperl\-mode.el) has been updated to version +4.31. +.IP \(bu 4 +\&\fIemacs/e2ctags.pl\fR is now much faster. +.IP \(bu 4 +\&\f(CW\*(C`enc2xs\*(C'\fR is a tool for people adding their own encodings to the +Encode module. +.IP \(bu 4 +\&\f(CW\*(C`h2ph\*(C'\fR now supports C trigraphs. +.IP \(bu 4 +\&\f(CW\*(C`h2xs\*(C'\fR now produces a template README. +.IP \(bu 4 +\&\f(CW\*(C`h2xs\*(C'\fR now uses \f(CW\*(C`Devel::PPPort\*(C'\fR for better portability between +different versions of Perl. +.IP \(bu 4 +\&\f(CW\*(C`h2xs\*(C'\fR 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 \fBnever\fR +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. +.IP \(bu 4 +\&\f(CW\*(C`libnetcfg\*(C'\fR has been added to configure libnet. +.IP \(bu 4 +\&\f(CW\*(C`perlbug\*(C'\fR is now much more robust. It also sends the bug report to +perl.org, not perl.com. +.IP \(bu 4 +\&\f(CW\*(C`perlcc\*(C'\fR 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 \f(CW\*(C`perlcc \-B\*(C'\fR instead.) +\&\fBNote that perlcc is still considered very experimental and +unsupported.\fR [561] +.IP \(bu 4 +\&\f(CW\*(C`perlivp\*(C'\fR is a new Installation Verification Procedure utility +for running any time after installing Perl. +.IP \(bu 4 +\&\f(CW\*(C`piconv\*(C'\fR is an implementation of the character conversion utility +\&\f(CW\*(C`iconv\*(C'\fR, demonstrating the new Encode module. +.IP \(bu 4 +\&\f(CW\*(C`pod2html\*(C'\fR now allows specifying a cache directory. +.IP \(bu 4 +\&\f(CW\*(C`pod2html\*(C'\fR now produces XHTML 1.0. +.IP \(bu 4 +\&\f(CW\*(C`pod2html\*(C'\fR now understands POD written using different line endings +(PC-like CRLF versus Unix-like LF versus MacClassic-like CR). +.IP \(bu 4 +\&\f(CW\*(C`s2p\*(C'\fR 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 \f(CW\*(C`psed\*(C'\fR utility.) +.IP \(bu 4 +\&\f(CW\*(C`xsubpp\*(C'\fR now understands POD documentation embedded in the *.xs +files. [561] +.IP \(bu 4 +\&\f(CW\*(C`xsubpp\*(C'\fR now supports the OUT keyword. +.SH "New Documentation" +.IX Header "New Documentation" +.IP \(bu 4 +perl56delta details the changes between the 5.005 release and the +5.6.0 release. +.IP \(bu 4 +perlclib documents the internal replacements for standard C library +functions. (Interesting only for extension writers and Perl core +hackers.) [561+] +.IP \(bu 4 +perldebtut is a Perl debugging tutorial. [561+] +.IP \(bu 4 +perlebcdic contains considerations for running Perl on EBCDIC +platforms. [561+] +.IP \(bu 4 +perlintro is a gentle introduction to Perl. +.IP \(bu 4 +perliol documents the internals of PerlIO with layers. +.IP \(bu 4 +perlmodstyle is a style guide for writing modules. +.IP \(bu 4 +perlnewmod tells about writing and submitting a new module. [561+] +.IP \(bu 4 +perlpacktut is a \fBpack()\fR tutorial. +.IP \(bu 4 +perlpod has been rewritten to be clearer and to record the best +practices gathered over the years. +.IP \(bu 4 +perlpodspec is a more formal specification of the pod format, +mainly of interest for writers of pod applications, not to +people writing in pod. +.IP \(bu 4 +perlretut is a regular expression tutorial. [561+] +.IP \(bu 4 +perlrequick is a regular expressions quick-start guide. +Yes, much quicker than perlretut. [561] +.IP \(bu 4 +perltodo has been updated. +.IP \(bu 4 +perltootc has been renamed as perltooc (to not to conflict +with perltoot in filesystems restricted to "8.3" names). +.IP \(bu 4 +perluniintro is an introduction to using Unicode in Perl. +(perlunicode is more of a detailed reference and background +information) +.IP \(bu 4 +perlutil explains the command line utilities packaged with the Perl +distribution. [561+] +.PP +The following platform-specific documents are available before +the installation as README.\fIplatform\fR, and after the installation +as perl\fIplatform\fR: +.PP +.Vb 5 +\& 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 +.Ve +.PP +These documents usually detail one or more of the following subjects: +configuring, building, testing, installing, and sometimes also using +Perl on the said platform. +.PP +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 +.PP +.Vb 1 +\& perljp perlko perlcn perltw +.Ve +.IP \(bu 4 +The documentation for the POSIX-BC platform is called "BS2000", to avoid +confusion with the Perl POSIX module. +.IP \(bu 4 +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. +.SH "Performance Enhancements" +.IX Header "Performance Enhancements" +.IP \(bu 4 +\&\fBmap()\fR 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] +.IP \(bu 4 +\&\fBsort()\fR is also fully reentrant, in the sense that the sort function +can itself call \fBsort()\fR. This did not work reliably in previous +releases. [561] +.IP \(bu 4 +\&\fBsort()\fR 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 \fBsort()\fR 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 \fBsort()\fR is now stable +(meaning that elements with identical keys will stay ordered as they +were before the sort). See the \f(CW\*(C`sort\*(C'\fR pragma for information. +.Sp +The story in more detail: suppose you want to serve yourself a little +slice of Pi. +.Sp +.Vb 1 +\& @digits = ( 3,1,4,1,5,9 ); +.Ve +.Sp +A numerical sort of the digits will yield (1,1,3,4,5,9), as expected. +Which \f(CW1\fR comes first is hard to know, since one \f(CW1\fR 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 +.Sp +.Vb 1 +\& sort { ($a % 2) <=> ($b % 2) } @digits; +.Ve +.Sp +yield? The only even digit, \f(CW4\fR, 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 +.Sp +.Vb 1 +\& sort { $a <=> $b } ( 1 .. $N , 1 .. $N ); +.Ve +.Sp +(something you might approximate if you wanted to merge two sorted +arrays using sort), doubling \f(CW$N\fR doesn't just double the quicksort time, +it \fIquadruples\fR it. Quicksort has a worst case run time that can +grow like N**2, so-called \fIquadratic\fR behaviour, and it can happen +on patterns that may well arise in normal use. You won't notice this +for small arrays, but you \fIwill\fR 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. +.Sp +Because of the unpredictability of tie-breaking order, and the quadratic +worst-case behaviour, quicksort was \fIalmost\fR replaced completely with +a stable mergesort. \fIStable\fR means that ties are broken to preserve +the original order of appearance in the input array. So +.Sp +.Vb 1 +\& sort { ($a % 2) <=> ($b % 2) } (3,1,4,1,5,9); +.Ve +.Sp +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 \fIdon't\fR 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. +.Sp +Quicksort was rescued by implementing a sort pragma to control aspects +of the sort. The \fBstable\fR subpragma forces stable behaviour, +regardless of algorithm. The \fB_quicksort\fR and \fB_mergesort\fR +subpragmas are heavy-handed ways to select the underlying implementation. +The leading \f(CW\*(C`_\*(C'\fR 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. +.IP \(bu 4 +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. +.IP \(bu 4 +\&\fBunshift()\fR should now be noticeably faster. +.SH "Installation and Configuration Improvements" +.IX Header "Installation and Configuration Improvements" +.SS "Generic Improvements" +.IX Subsection "Generic Improvements" +.IP \(bu 4 +INSTALL now explains how you can configure Perl to use 64\-bit +integers even on non\-64\-bit platforms. +.IP \(bu 4 +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 \f(CW$prefix\fR eq \f(CW$siteprefix\fR and \f(CW$prefix\fR eq \f(CW$vendorprefix\fR, all of +them will now be changed to the new prefix, /foo/bar. (Previously +only \f(CW$prefix\fR changed.) If you do not like this new behaviour, +specify prefix, siteprefix, and vendorprefix explicitly. +.IP \(bu 4 +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. +.IP \(bu 4 +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. +.IP \(bu 4 +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. +.IP \(bu 4 +Since Perl 5.8 is not binary-compatible with previous releases +of Perl, Configure no longer suggests including the 5.005 +modules in \f(CW@INC\fR. +.IP \(bu 4 +Configure \f(CW\*(C`\-S\*(C'\fR can now run non-interactively. [561] +.IP \(bu 4 +Configure support for pdp11\-style memory models has been removed due +to obsolescence. [561] +.IP \(bu 4 +configure.gnu now works with options with whitespace in them. +.IP \(bu 4 +installperl now outputs everything to STDERR. +.IP \(bu 4 +Because PerlIO is now the default on most platforms, "\-perlio" doesn't +get appended to the \f(CW$Config\fR{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. +.IP \(bu 4 +Another change related to the architecture name is that "\-64all" +(\-Duse64bitall, or "maximally 64\-bit") is appended only if your +pointers are 64 bits wide. (To be exact, the use64bitall is ignored.) +.IP \(bu 4 +In AFS installations, one can configure the root of the AFS to be +somewhere else than the default \fI/afs\fR by using the Configure +parameter \f(CW\*(C`\-Dafsroot=/some/where/else\*(C'\fR. +.IP \(bu 4 +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. +.IP \(bu 4 +The version of Berkeley DB used when the Perl (and, presumably, the +DB_File extension) was built is now available as +\&\f(CW@Config{qw(db_version_major db_version_minor db_version_patch)}\fR +from Perl and as \f(CW\*(C`DB_VERSION_MAJOR_CFG DB_VERSION_MINOR_CFG +DB_VERSION_PATCH_CFG\*(C'\fR from C. +.IP \(bu 4 +Building Berkeley DB3 for compatibility modes for DB, NDBM, and ODBM +has been documented in INSTALL. +.IP \(bu 4 +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. +.IP \(bu 4 +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). +.IP \(bu 4 +If your file system supports symbolic links, you can build Perl outside +of the source directory by +.Sp +.Vb 3 +\& mkdir perl/build/directory +\& cd perl/build/directory +\& sh /path/to/perl/source/Configure \-Dmksymlinks ... +.Ve +.Sp +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 +.Sp +.Vb 1 +\& make all test +.Ve +.Sp +and Perl will be built and tested, all in perl/build/directory. +[561] +.IP \(bu 4 +For Perl developers, several new make targets for profiling +and debugging have been added; see perlhack. +.RS 4 +.IP \(bu 8 +Use of the \fIgprof\fR tool to profile Perl has been documented in +perlhack. There is a make target called "perl.gprof" for +generating a gprofiled Perl executable. +.IP \(bu 8 +If you have GCC 3, there is a make target called "perl.gcov" for +creating a gcoved Perl executable for coverage analysis. See +perlhack. +.IP \(bu 8 +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. +.RE +.RS 4 +.RE +.IP \(bu 4 +Guidelines of how to construct minimal Perl installations have +been added to INSTALL. +.IP \(bu 4 +The Thread extension is now not built at all under ithreads +(\f(CW\*(C`Configure \-Duseithreads\*(C'\fR) because it wouldn't work anyway (the +Thread extension requires being Configured with \f(CW\*(C`\-Duse5005threads\*(C'\fR). +.Sp +\&\fBNote 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.\fR +.IP \(bu 4 +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. +.IP \(bu 4 +The obsolete method of making a special (e.g., debugging) flavor +of perl by saying +.Sp +.Vb 1 +\& make LIBPERL=libperld.a +.Ve +.Sp +has been removed. Use \-DDEBUGGING instead. +.SS "New Or Improved Platforms" +.IX Subsection "New Or Improved Platforms" +For the list of platforms known to support Perl, +see "Supported Platforms" in perlport. +.IP \(bu 4 +AIX dynamic loading should be now better supported. +.IP \(bu 4 +AIX should now work better with gcc, threads, and 64\-bitness. Also the +long doubles support in AIX should be better now. See perlaix. +.IP \(bu 4 +AtheOS ( http://www.atheos.cx/ ) is a new platform. +.IP \(bu 4 +BeOS has been reclaimed. +.IP \(bu 4 +The DG/UX platform now supports 5.005\-style threads. +See perldgux. +.IP \(bu 4 +The DYNIX/ptx platform (also known as dynixptx) is supported at or +near osvers 4.5.2. +.IP \(bu 4 +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. +(\fBNote:\fR support for VM/ESA was removed in Perl v5.18.0. The relevant +information was in \fIREADME.vmesa\fR) +.IP \(bu 4 +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] +.IP \(bu 4 +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] +.IP \(bu 4 +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.) +.IP \(bu 4 +NCR MP-RAS is now supported. [561] +.IP \(bu 4 +All the NetBSD specific patches (except for the installation +specific ones) have been merged back to the main distribution. +.IP \(bu 4 +NetWare from Novell is now supported. See perlnetware. +.IP \(bu 4 +NonStop-UX is now supported. [561] +.IP \(bu 4 +NEC SUPER-UX is now supported. +.IP \(bu 4 +All the OpenBSD specific patches (except for the installation +specific ones) have been merged back to the main distribution. +.IP \(bu 4 +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 \fByield()\fRs 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. +.IP \(bu 4 +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+] +.IP \(bu 4 +The Amdahl UTS Unix mainframe platform is now supported. [561] +.IP \(bu 4 +WinCE is now supported. See perlce. +.IP \(bu 4 +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] +.SH "Selected Bug Fixes" +.IX Header "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] +.IP \(bu 4 +The autouse pragma didn't work for Multi::Part::Function::Names. +.IP \(bu 4 +\&\fBcaller()\fR could cause core dumps in certain situations. Carp was +sometimes affected by this problem. In particular, \fBcaller()\fR now +returns a subroutine name of \f(CW\*(C`(unknown)\*(C'\fR for subroutines that have +been removed from the symbol table. +.IP \(bu 4 +chop(@list) in list context returned the characters chopped in +reverse order. This has been reversed to be in the right order. [561] +.IP \(bu 4 +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] +.IP \(bu 4 +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. +.IP \(bu 4 +Several debugger fixes: exit code now reflects the script exit code, +condition \f(CW"0"\fR now treated correctly, the \f(CW\*(C`d\*(C'\fR command now checks +line number, \f(CW$.\fR no longer gets corrupted, and all debugger output +now goes correctly to the socket if RemotePort is set. [561] +.IP \(bu 4 +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. +.Sp +See perldebug. +.IP \(bu 4 +The debugger has a new \f(CW\*(C`dumpDepth\*(C'\fR option to control the maximum +depth to which nested structures are dumped. The \f(CW\*(C`x\*(C'\fR command has +been extended so that \f(CW\*(C`x N EXPR\*(C'\fR dumps out the value of \fIEXPR\fR to a +depth of at most \fIN\fR levels. +.IP \(bu 4 +The debugger can now show lexical variables if you have the CPAN +module PadWalker installed. +.IP \(bu 4 +The order of DESTROYs has been made more predictable. +.IP \(bu 4 +Perl 5.6.0 could emit spurious warnings about redefinition of +\&\fBdl_error()\fR when statically building extensions into perl. +This has been corrected. [561] +.IP \(bu 4 +dprofpp \-R didn't work. +.IP \(bu 4 +\&\f(CW*foo{FORMAT}\fR now works. +.IP \(bu 4 +Infinity is now recognized as a number. +.IP \(bu 4 +UNIVERSAL::isa no longer caches methods incorrectly. (This broke +the Tk extension with 5.6.0.) [561] +.IP \(bu 4 +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. +.IP \(bu 4 +Lexicals II: lexicals leaked at file scope into subroutines that +were declared before the lexicals. +.IP \(bu 4 +Lexical warnings now propagating correctly between scopes +and into \f(CW\*(C`eval "..."\*(C'\fR. +.IP \(bu 4 +\&\f(CW\*(C`use warnings qw(FATAL all)\*(C'\fR did not work as intended. This has been +corrected. [561] +.IP \(bu 4 +\&\fBwarnings::enabled()\fR now reports the state of $^W correctly if the caller +isn't using lexical warnings. [561] +.IP \(bu 4 +Line renumbering with eval and \f(CW\*(C`#line\*(C'\fR now works. [561] +.IP \(bu 4 +Fixed numerous memory leaks, especially in eval "". +.IP \(bu 4 +Localised tied variables no longer leak memory +.Sp +.Vb 2 +\& use Tie::Hash; +\& tie my %tied_hash => \*(AqTie::StdHash\*(Aq; +\& +\& ... +\& +\& # Used to leak memory every time local() was called; +\& # in a loop, this added up. +\& local($tied_hash{Foo}) = 1; +.Ve +.IP \(bu 4 +Localised hash elements (and \f(CW%ENV\fR) are correctly unlocalised to not +exist, if they didn't before they were localised. +.Sp +.Vb 2 +\& use Tie::Hash; +\& tie my %tied_hash => \*(AqTie::StdHash\*(Aq; +\& +\& ... +\& +\& # Nothing has set the FOO element so far +\& +\& { local $tied_hash{FOO} = \*(AqBar\*(Aq } +\& +\& # This used to print, but not now. +\& print "exists!\en" if exists $tied_hash{FOO}; +.Ve +.Sp +As a side effect of this fix, tied hash interfaces \fBmust\fR define +the EXISTS and DELETE methods. +.IP \(bu 4 +\&\fBmkdir()\fR now ignores trailing slashes in the directory name, +as mandated by POSIX. +.IP \(bu 4 +Some versions of glibc have a broken \fBmodfl()\fR. This affects builds +with \f(CW\*(C`\-Duselongdouble\*(C'\fR. 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 \fBmodfl()\fR bug. +.IP \(bu 4 +Modulus of unsigned numbers now works (4063328477 % 65535 used to +return 27406, instead of 27047). [561] +.IP \(bu 4 +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] +.IP \(bu 4 +Numeric conversions did not recognize changes in the string value +properly in certain circumstances. [561] +.IP \(bu 4 +Attributes (such as :shared) didn't work with \fBour()\fR. +.IP \(bu 4 +\&\fBour()\fR variables will not cause bogus "Variable will not stay shared" +warnings. [561] +.IP \(bu 4 +"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] +.IP \(bu 4 +pack "Z" now correctly terminates the string with "\e0". +.IP \(bu 4 +Fix password routines which in some shadow password platforms +(e.g. HP-UX) caused \fBgetpwent()\fR to return every other entry. +.IP \(bu 4 +The PERL5OPT environment variable (for passing command line arguments +to Perl) didn't work for more than a single group of options. [561] +.IP \(bu 4 +PERL5OPT with embedded spaces didn't work. +.IP \(bu 4 +\&\fBprintf()\fR no longer resets the numeric locale to "C". +.IP \(bu 4 +\&\f(CWqw(a\e\eb)\fR now parses correctly as \f(CW\*(Aqa\e\eb\*(Aq\fR: that is, as three +characters, not four. [561] +.IP \(bu 4 +\&\fBpos()\fR did not return the correct value within s///ge in earlier +versions. This is now handled correctly. [561] +.IP \(bu 4 +Printing quads (64\-bit integers) with printf/sprintf now works +without the q L ll prefixes (assuming you are on a quad-capable platform). +.IP \(bu 4 +Regular expressions on references and overloaded scalars now work. [561+] +.IP \(bu 4 +Right-hand side magic (GMAGIC) could in many cases such as string +concatenation be invoked too many times. +.IP \(bu 4 +\&\fBscalar()\fR now forces scalar context even when used in void context. +.IP \(bu 4 +SOCKS support is now much more robust. +.IP \(bu 4 +\&\fBsort()\fR arguments are now compiled in the right wantarray context +(they were accidentally using the context of the \fBsort()\fR itself). +The comparison block is now run in scalar context, and the arguments +to be sorted are always provided list context. [561] +.IP \(bu 4 +Changed the POSIX character class \f(CW\*(C`[[:space:]]\*(C'\fR to include the (very +rarely used) vertical tab character. Added a new POSIX-ish character +class \f(CW\*(C`[[:blank:]]\*(C'\fR which stands for horizontal whitespace +(currently, the space and the tab). +.IP \(bu 4 +The tainting behaviour of \fBsprintf()\fR has been rationalized. It does +not taint the result of floating point formats anymore, making the +behaviour consistent with that of string interpolation. [561] +.IP \(bu 4 +Some cases of inconsistent taint propagation (such as within hash +values) have been fixed. +.IP \(bu 4 +The RE engine found in Perl 5.6.0 accidentally pessimised certain kinds +of simple pattern matches. These are now handled better. [561] +.IP \(bu 4 +Regular expression debug output (whether through \f(CW\*(C`use re \*(Aqdebug\*(Aq\*(C'\fR +or via \f(CW\*(C`\-Dr\*(C'\fR) now looks better. [561] +.IP \(bu 4 +Multi-line matches like \f(CW\*(C`"a\enxb\en" =~ /(?!\eA)x/m\*(C'\fR were flawed. The +bug has been fixed. [561] +.IP \(bu 4 +Use of $& could trigger a core dump under some situations. This +is now avoided. [561] +.IP \(bu 4 +The regular expression captured submatches ($1, \f(CW$2\fR, ...) are now +more consistently unset if the match fails, instead of leaving false +data lying around in them. [561] +.IP \(bu 4 +\&\fBreadline()\fR on files opened in "slurp" mode could return an extra +"" (blank line) at the end in certain situations. This has been +corrected. [561] +.IP \(bu 4 +Autovivification of symbolic references of special variables described +in perlvar (as in \f(CW\*(C`${$num}\*(C'\fR) was accidentally disabled. This works +again now. [561] +.IP \(bu 4 +Sys::Syslog ignored the \f(CW\*(C`LOG_AUTH\*(C'\fR constant. +.IP \(bu 4 +\&\f(CW$AUTOLOAD\fR, \fBsort()\fR, \fBlock()\fR, and spawning subprocesses +in multiple threads simultaneously are now thread-safe. +.IP \(bu 4 +Tie::Array's SPLICE method was broken. +.IP \(bu 4 +Allow a read-only string on the left-hand side of a non-modifying tr///. +.IP \(bu 4 +If \f(CW\*(C`STDERR\*(C'\fR is tied, warnings caused by \f(CW\*(C`warn\*(C'\fR and \f(CW\*(C`die\*(C'\fR now +correctly pass to it. +.IP \(bu 4 +Several Unicode fixes. +.RS 4 +.IP \(bu 8 +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. +.IP \(bu 8 +The character tables have been updated to Unicode 3.2.0. +.IP \(bu 8 +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.) +.IP \(bu 8 +Generating illegal Unicode code points such as U+FFFE, or the UTF\-16 +surrogates, now also generates an optional warning. +.IP \(bu 8 +\&\f(CW\*(C`IsAlnum\*(C'\fR, \f(CW\*(C`IsAlpha\*(C'\fR, and \f(CW\*(C`IsWord\*(C'\fR now match titlecase. +.IP \(bu 8 +Concatenation with the \f(CW\*(C`.\*(C'\fR operator or via variable interpolation, +\&\f(CW\*(C`eq\*(C'\fR, \f(CW\*(C`substr\*(C'\fR, \f(CW\*(C`reverse\*(C'\fR, \f(CW\*(C`quotemeta\*(C'\fR, the \f(CW\*(C`x\*(C'\fR operator, +substitution with \f(CW\*(C`s///\*(C'\fR, single-quoted UTF\-8, should now work. +.IP \(bu 8 +The \f(CW\*(C`tr///\*(C'\fR operator now works. Note that the \f(CW\*(C`tr///CU\*(C'\fR +functionality has been removed (but see pack('U0', ...)). +.IP \(bu 8 +\&\f(CW\*(C`eval "v200"\*(C'\fR now works. +.IP \(bu 8 +Perl 5.6.0 parsed m/\ex{ab}/ incorrectly, leading to spurious warnings. +This has been corrected. [561] +.IP \(bu 8 +Zero entries were missing from the Unicode classes such as \f(CW\*(C`IsDigit\*(C'\fR. +.RE +.RS 4 +.RE +.IP \(bu 4 +Large unsigned numbers (those above 2**31) could sometimes lose their +unsignedness, causing bogus results in arithmetic operations. [561] +.IP \(bu 4 +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. +.SS "Platform Specific Changes and Fixes" +.IX Subsection "Platform Specific Changes and Fixes" +.IP \(bu 4 +BSDI 4.* +.Sp +Perl now works on post\-4.0 BSD/OSes. +.IP \(bu 4 +All BSDs +.Sp +Setting \f(CW$0\fR now works (as much as possible; see perlvar for details). +.IP \(bu 4 +Cygwin +.Sp +Numerous updates; currently synchronised with Cygwin 1.3.10. +.IP \(bu 4 +Previously DYNIX/ptx had problems in its Configure probe for non-blocking I/O. +.IP \(bu 4 +EPOC +.Sp +EPOC now better supported. See README.epoc. [561] +.IP \(bu 4 +FreeBSD 3.* +.Sp +Perl now works on post\-3.0 FreeBSDs. +.IP \(bu 4 +HP-UX +.Sp +README.hpux updated; \f(CW\*(C`Configure \-Duse64bitall\*(C'\fR now works; +now uses HP-UX malloc instead of Perl malloc. +.IP \(bu 4 +IRIX +.Sp +Numerous compilation flag and hint enhancements; accidental mixing +of 32\-bit and 64\-bit libraries (a doomed attempt) made much harder. +.IP \(bu 4 +Linux +.RS 4 +.IP \(bu 8 +Long doubles should now work (see INSTALL). [561] +.IP \(bu 8 +Linux previously had problems related to sockaddrlen when using +\&\fBaccept()\fR, \fBrecvfrom()\fR (in Perl: \fBrecv()\fR), \fBgetpeername()\fR, and +\&\fBgetsockname()\fR. +.RE +.RS 4 +.RE +.IP \(bu 4 +Mac OS Classic +.Sp +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. +.IP \(bu 4 +MPE/iX +.Sp +MPE/iX update after Perl 5.6.0. See README.mpeix. [561] +.IP \(bu 4 +NetBSD/threads: try installing the GNU pth (should be in the +packages collection, or http://www.gnu.org/software/pth/), +and Configure with \-Duseithreads. +.IP \(bu 4 +NetBSD/sparc +.Sp +Perl now works on NetBSD/sparc. +.IP \(bu 4 +OS/2 +.Sp +Now works with usethreads (see INSTALL). [561] +.IP \(bu 4 +Solaris +.Sp +64\-bitness using the Sun Workshop compiler now works. +.IP \(bu 4 +Stratus VOS +.Sp +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. +.IP \(bu 4 +Tru64 (aka Digital UNIX, aka DEC OSF/1) +.Sp +The operating system version letter now recorded in \f(CW$Config\fR{osvers}. +Allow compiling with gcc (previously explicitly forbidden). Compiling +with gcc still not recommended because buggy code results, even with +gcc 2.95.2. +.IP \(bu 4 +Unicos +.Sp +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. +.IP \(bu 4 +VMS +.Sp +See "Socket Extension Dynamic in VMS" and "IEEE-format Floating Point +Default on OpenVMS Alpha" for important changes not otherwise listed here. +.Sp +\&\fBchdir()\fR now works better despite a CRT bug; now works with MULTIPLICITY +(see INSTALL); now works with Perl's malloc. +.Sp +The tainting of \f(CW%ENV\fR elements via \f(CW\*(C`keys\*(C'\fR or \f(CW\*(C`values\*(C'\fR was previously +unimplemented. It now works as documented. +.Sp +The \f(CW\*(C`waitpid\*(C'\fR 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. +.Sp +POSIX-style signals are now emulated much better on VMS versions prior +to 7.0. +.Sp +The \f(CW\*(C`system\*(C'\fR function and backticks operator have improved +functionality and better error handling. [561] +.Sp +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. +.Sp +There is a new \f(CW\*(C`kill\*(C'\fR implementation based on \f(CW\*(C`sys$sigprc\*(C'\fR that allows +older VMS systems (pre\-7.0) to use \f(CW\*(C`kill\*(C'\fR to send signals rather than +simply force exit. This implementation also allows later systems to +call \f(CW\*(C`kill\*(C'\fR from within a signal handler. +.Sp +Iterative logical name translations are now limited to 10 iterations in +imitation of SHOW LOGICAL and other OpenVMS facilities. +.IP \(bu 4 +Windows +.RS 4 +.IP \(bu 8 +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. +.IP \(bu 8 +\&\fBfork()\fR emulation is now more robust, but still continues to have a few +esoteric bugs and caveats. See perlfork for details. [561+] +.IP \(bu 8 +A failed (pseudo)fork now returns undef and sets errno to EAGAIN. [561] +.IP \(bu 8 +The following modules now work on Windows: +.Sp +.Vb 4 +\& ExtUtils::Embed [561] +\& IO::Pipe +\& IO::Poll +\& Net::Ping +.Ve +.IP \(bu 8 +\&\fBIO::File::new_tmpfile()\fR is no longer limited to 32767 invocations +per-process. +.IP \(bu 8 +Better \fBchdir()\fR return value for a non-existent directory. +.IP \(bu 8 +Compiling perl using the 64\-bit Platform SDK tools is now supported. +.IP \(bu 8 +The \fBWin32::SetChildShowWindow()\fR builtin can be used to control the +visibility of windows created by child processes. See Win32 for +details. +.IP \(bu 8 +Non-blocking waits for child processes (or pseudo-processes) are +supported via \f(CW\*(C`waitpid($pid, &POSIX::WNOHANG)\*(C'\fR. +.IP \(bu 8 +The behavior of \fBsystem()\fR 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 \f(CW\*(C`cmd\*(C'\fR shell specific quoting in perl programs. +.Sp +Note that this means that some scripts that may have relied on earlier +buggy behavior may no longer work correctly. For example, +\&\f(CW\*(C`system("nmake /nologo", @args)\*(C'\fR will now attempt to run the file +\&\f(CW\*(C`nmake /nologo\*(C'\fR and will fail when such a file isn't found. +On the other hand, perl will now execute code such as +\&\f(CW\*(C`system("c:/Program Files/MyApp/foo.exe", @args)\*(C'\fR correctly. +.IP \(bu 8 +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. +.IP \(bu 8 +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] +.IP \(bu 8 +Duping socket handles with open(F, ">&MYSOCK") now works under Windows 9x. +[561] +.IP \(bu 8 +Current directory entries in \f(CW%ENV\fR are now correctly propagated to child +processes. [561] +.IP \(bu 8 +New \f(CW%ENV\fR entries now propagate to subprocesses. [561] +.IP \(bu 8 +\&\fBWin32::GetCwd()\fR correctly returns C:\e instead of C: when at the drive root. +Other bugs in \fBchdir()\fR and \fBCwd::cwd()\fR have also been fixed. [561] +.IP \(bu 8 +The makefiles now default to the features enabled in ActiveState ActivePerl +(a popular Win32 binary distribution). [561] +.IP \(bu 8 +HTML files will now be installed in c:\eperl\ehtml instead of +c:\eperl\elib\epod\ehtml +.IP \(bu 8 +REG_EXPAND_SZ keys are now allowed in registry settings used by perl. [561] +.IP \(bu 8 +Can now \fBsend()\fR from all threads, not just the first one. [561] +.IP \(bu 8 +ExtUtils::MakeMaker now uses \f(CW$ENV\fR{LIB} to search for libraries. [561] +.IP \(bu 8 +Less stack reserved per thread so that more threads can run +concurrently. (Still 16M per thread.) [561] +.IP \(bu 8 +\&\f(CW\*(C`File::Spec\->tmpdir()\*(C'\fR now prefers C:/temp over /tmp +(works better when perl is running as service). +.IP \(bu 8 +Better UNC path handling under ithreads. [561] +.IP \(bu 8 +\&\fBwait()\fR, \fBwaitpid()\fR, and backticks now return the correct exit status +under Windows 9x. [561] +.IP \(bu 8 +A socket handle leak in \fBaccept()\fR has been fixed. [561] +.RE +.RS 4 +.RE +.SH "New or Changed Diagnostics" +.IX Header "New or Changed Diagnostics" +Please see perldiag for more details. +.IP \(bu 4 +Ambiguous range in the transliteration operator (like a\-z\-9) now +gives a warning. +.IP \(bu 4 +chdir("") and chdir(undef) now give a deprecation warning because they +cause a possible unintentional chdir to the home directory. +Say \fBchdir()\fR if you really mean that. +.IP \(bu 4 +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. +.IP \(bu 4 +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. +.IP \(bu 4 +Unadorned \fBdump()\fR will now give a warning suggesting to +use explicit \fBCORE::dump()\fR if that's what really is meant. +.IP \(bu 4 +The "Unrecognized escape" warning has been extended to include \f(CW\*(C`\e8\*(C'\fR, +\&\f(CW\*(C`\e9\*(C'\fR, and \f(CW\*(C`\e_\*(C'\fR. There is no need to escape any of the \f(CW\*(C`\ew\*(C'\fR characters. +.IP \(bu 4 +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 \f(CW\*(C`<\-\- HERE\*(C'\fR marker. +.IP \(bu 4 +Various I/O (and socket) functions like \fBbinmode()\fR, \fBclose()\fR, 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). +.IP \(bu 4 +Using \fBlstat()\fR on a filehandle now gives a warning. (It's a non-sensical +thing to do.) +.IP \(bu 4 +The \f(CW\*(C`\-M\*(C'\fR and \f(CW\*(C`\-m\*(C'\fR options now warn if you didn't supply the module name. +.IP \(bu 4 +If you in \f(CW\*(C`use\*(C'\fR specify a required minimum version, modules matching +the name and but not defining a \f(CW$VERSION\fR will cause a fatal failure. +.IP \(bu 4 +Using negative offset for \fBvec()\fR in lvalue context is now a warnable offense. +.IP \(bu 4 +Odd number of arguments to overload::constant now elicits a warning. +.IP \(bu 4 +Odd number of elements in anonymous hash now elicits a warning. +.IP \(bu 4 +The various "opened only for", "on closed", "never opened" warnings +drop the \f(CW\*(C`main::\*(C'\fR prefix for filehandles in the \f(CW\*(C`main\*(C'\fR package, +for example \f(CW\*(C`STDIN\*(C'\fR instead of \f(CW\*(C`main::STDIN\*(C'\fR. +.IP \(bu 4 +Subroutine prototypes are now checked more carefully, you may +get warnings for example if you have used non-prototype characters. +.IP \(bu 4 +If an attempt to use a (non-blessed) reference as an array index +is made, a warning is given. +.IP \(bu 4 +\&\f(CW\*(C`push @a;\*(C'\fR and \f(CW\*(C`unshift @a;\*(C'\fR (with no values to push or unshift) +now give a warning. This may be a problem for generated and eval'ed +code. +.IP \(bu 4 +If you try to "pack" in perlfunc a number less than 0 or larger than 255 +using the \f(CW"C"\fR format you will get an optional warning. Similarly +for the \f(CW"c"\fR format and a number less than \-128 or more than 127. +.IP \(bu 4 +pack \f(CW\*(C`P\*(C'\fR format now demands an explicit size. +.IP \(bu 4 +unpack \f(CW\*(C`w\*(C'\fR now warns of unterminated compressed integers. +.IP \(bu 4 +Warnings relating to the use of PerlIO have been added. +.IP \(bu 4 +Certain regex modifiers such as \f(CW\*(C`(?o)\*(C'\fR make sense only if applied to +the entire regex. You will get an optional warning if you try to do +otherwise. +.IP \(bu 4 +Variable length lookbehind has not yet been implemented, trying to +use it will tell that. +.IP \(bu 4 +Using arrays or hashes as references (e.g. \f(CW\*(C`%foo\->{bar}\*(C'\fR +has been deprecated for a while. Now you will get an optional warning. +.IP \(bu 4 +Warnings relating to the use of the new restricted hashes feature +have been added. +.IP \(bu 4 +Self-ties of arrays and hashes are not supported and fatal errors +will happen even at an attempt to do so. +.IP \(bu 4 +Using \f(CW\*(C`sort\*(C'\fR in scalar context now issues an optional warning. +This didn't do anything useful, as the sort was not performed. +.IP \(bu 4 +Using the /g modifier in \fBsplit()\fR is meaningless and will cause a warning. +.IP \(bu 4 +Using \fBsplice()\fR past the end of an array now causes a warning. +.IP \(bu 4 +Malformed Unicode encodings (UTF\-8 and UTF\-16) cause a lot of warnings, +as does trying to use UTF\-16 surrogates (which are unimplemented). +.IP \(bu 4 +Trying to use Unicode characters on an I/O stream without marking the +stream's encoding (using \fBopen()\fR or \fBbinmode()\fR) will cause "Wide character" +warnings. +.IP \(bu 4 +Use of v\-strings in use/require causes a (backward) portability warning. +.IP \(bu 4 +Warnings relating to the use interpreter threads and their shared data +have been added. +.SH "Changed Internals" +.IX Header "Changed Internals" +.IP \(bu 4 +PerlIO is now the default. +.IP \(bu 4 +perlapi.pod (a companion to perlguts) now attempts to document the +internal API. +.IP \(bu 4 +You can now build a really minimal perl called microperl. +Building microperl does not require even running Configure; +\&\f(CW\*(C`make \-f Makefile.micro\*(C'\fR 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. +.IP \(bu 4 +Added \fBrsignal()\fR, \fBwhichsig()\fR, \fBdo_join()\fR, op_clear, op_null, +\&\fBptr_table_clear()\fR, \fBptr_table_free()\fR, \fBsv_setref_uv()\fR, and several UTF\-8 +interfaces to the publicised API. For the full list of the available +APIs see perlapi. +.IP \(bu 4 +Made possible to propagate customised exceptions via \fBcroak()\fRing. +.IP \(bu 4 +Now xsubs can have attributes just like subs. (Well, at least the +built-in attributes.) +.IP \(bu 4 +dTHR and djSP have been obsoleted; the former removed (because it's +a no-op) and the latter replaced with dSP. +.IP \(bu 4 +PERL_OBJECT has been completely removed. +.IP \(bu 4 +The MAGIC constants (e.g. \f(CW\*(AqP\*(Aq\fR) have been macrofied +(e.g. \f(CW\*(C`PERL_MAGIC_TIED\*(C'\fR) for better source code readability +and maintainability. +.IP \(bu 4 +The regex compiler now maintains a structure that identifies nodes in +the compiled bytecode with the corresponding syntactic features of the +original regex expression. The information is attached to the new +\&\f(CW\*(C`offsets\*(C'\fR member of the \f(CW\*(C`struct regexp\*(C'\fR. See perldebguts for more +complete information. +.IP \(bu 4 +The C code has been made much more \f(CW\*(C`gcc \-Wall\*(C'\fR 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. +.IP \(bu 4 +\&\fIperly.c\fR, \fIsv.c\fR, and \fIsv.h\fR have now been extensively commented. +.IP \(bu 4 +Documentation on how to use the Perl source repository has been added +to \fIPorting/repository.pod\fR. +.IP \(bu 4 +There are now several profiling make targets. +.SH "Security Vulnerability Closed [561]" +.IX Header "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) +.PP +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. +.PP +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. +.PP +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/ ). +.SH "New Tests" +.IX Header "New Tests" +Several new tests have been added, especially for the \fIlib\fR and +\&\fIext\fR 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. +.PP +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). +.PP +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.) +.SH "Known Problems" +.IX Header "Known Problems" +.SS "The Compiler Suite Is Still Very Experimental" +.IX Subsection "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. +.SS "Localising Tied Arrays and Hashes Is Broken" +.IX Subsection "Localising Tied Arrays and Hashes Is Broken" +.Vb 1 +\& local %tied_array; +.Ve +.PP +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. +.SS "Building Extensions Can Fail Because Of Largefiles" +.IX Subsection "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 \f(CW%Config\fR hash (e.g., \f(CW$Config\fR{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. +.ie n .SS "Modifying $_ Inside for(..)" +.el .SS "Modifying \f(CW$_\fP Inside for(..)" +.IX Subsection "Modifying $_ Inside for(..)" +.Vb 1 +\& for (1..5) { $_++ } +.Ve +.PP +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. +.SS "mod_perl 1.26 Doesn't Build With Threaded Perl" +.IX Subsection "mod_perl 1.26 Doesn't Build With Threaded Perl" +Use mod_perl 1.27 or higher. +.SS "lib/ftmp\-security tests warn 'system possibly insecure'" +.IX Subsection "lib/ftmp-security tests warn 'system possibly insecure'" +Don't panic. Read the 'make test' section of INSTALL instead. +.SS "libwww-perl (LWP) fails base/date #51" +.IX Subsection "libwww-perl (LWP) fails base/date #51" +Use libwww-perl 5.65 or later. +.SS "PDL failing some tests" +.IX Subsection "PDL failing some tests" +Use PDL 2.3.4 or later. +.SS Perl_get_sv +.IX Subsection "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. +.PP +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. +.SS "Self-tying Problems" +.IX Subsection "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). +.PP +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. +.PP +Self-tying of scalars and IO thingies works. +.SS ext/threads/t/libc +.IX Subsection "ext/threads/t/libc" +If this test fails, it indicates that your libc (C library) is not +threadsafe. This particular test stress tests the \fBlocaltime()\fR call to +find out whether it is threadsafe. See perlthrtut for more information. +.SS "Failure of Thread (5.005\-style) tests" +.IX Subsection "Failure of Thread (5.005-style) tests" +\&\fBNote 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.\fR +.PP +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. +.PP +.Vb 10 +\& ../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 +.Ve +.PP +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.) +.SS "Timing problems" +.IX Subsection "Timing problems" +The following tests may fail intermittently because of timing +problems, for example if the system is heavily loaded. +.PP +.Vb 5 +\& t/op/alarm.t +\& ext/Time/HiRes/HiRes.t +\& lib/Benchmark.t +\& lib/Memoize/t/expmod_t.t +\& lib/Memoize/t/speed.t +.Ve +.PP +In case of failure please try running them manually, for example +.PP +.Vb 1 +\& ./perl \-Ilib ext/Time/HiRes/HiRes.t +.Ve +.SS "Tied/Magical Array/Hash Elements Do Not Autovivify" +.IX Subsection "Tied/Magical Array/Hash Elements Do Not Autovivify" +For normal arrays \f(CW\*(C`$foo = \e$bar[1]\*(C'\fR will assign \f(CW\*(C`undef\*(C'\fR to +\&\f(CW$bar[1]\fR (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. +.SS "Unicode in package/class and subroutine names does not work" +.IX Subsection "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. +.PP +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. +.SH "Platform Specific Problems" +.IX Header "Platform Specific Problems" +.SS AIX +.IX Subsection "AIX" +.IP \(bu 4 +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. +.IP \(bu 4 +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 \fBtime()\fR and \fBgettimeofday()\fR) return broken values, and +therefore in AIX 4.2 Perl is not linked against libC_r. +.IP \(bu 4 +vac 5.0.0.0 May Produce Buggy Code For Perl +.Sp +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. +.IP \(bu 4 +If building threaded Perl, you may get compilation warning from pp_sys.c: +.Sp +.Vb 1 +\& "pp_sys.c", line 4651.39: 1506\-280 (W) Function argument assignment between types "unsigned char*" and "const void*" is not allowed. +.Ve +.Sp +This is harmless; it is caused by the \fBgetnetbyaddr()\fR and \fBgetnetbyaddr_r()\fR +having slightly different types for their first argument. +.SS "Alpha systems with old gccs fail several tests" +.IX Subsection "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.) +.SS AmigaOS +.IX Subsection "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). +.SS BeOS +.IX Subsection "BeOS" +The following tests fail on 5.8.0 Perl in BeOS Personal 5.03: +.PP +.Vb 6 +\& 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 +.Ve +.PP +(\fBNote:\fR more information was available in \fIREADME.beos\fR until support for +BeOS was removed in Perl v5.18.0) +.SS "Cygwin ""unable to remap""" +.IX Subsection "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 +.SS "Cygwin ndbm tests fail on FAT" +.IX Subsection "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: +.PP +.Vb 6 +\& ../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 +.Ve +.PP +NDBM_File fails and ODBM_File just coredumps. +.PP +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. +.SS "DJGPP Failures" +.IX Subsection "DJGPP Failures" +.Vb 8 +\& 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 +.Ve +.PP +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: +.PP +.Vb 2 +\& t/comp/cpp...........................FAILED at test 3 +\& t/op/inccode.........................(crash) +.Ve +.PP +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. +.SS "FreeBSD built with ithreads coredumps reading large directories" +.IX Subsection "FreeBSD built with ithreads coredumps reading large directories" +This is a known bug in FreeBSD 4.5's \fBreaddir_r()\fR, it has been fixed in +FreeBSD 4.6 (see perlfreebsd (README.freebsd)). +.SS "FreeBSD Failing locale Test 117 For ISO 8859\-15 Locales" +.IX Subsection "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 \exFF (y with diaeresis) and \exBE +(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 ) +.SS "IRIX fails ext/List/Util/t/shuffle.t or Digest::MD5" +.IX Subsection "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. +.PP +Similarly, building the Digest::MD5 extension has been +known to fail with "*** Termination code 139 (bu21)". +.PP +The cure is to drop optimization level (Configure \-Doptimize=\-O2). +.SS "HP-UX lib/posix Subtest 9 Fails When LP64\-Configured" +.IX Subsection "HP-UX lib/posix Subtest 9 Fails When LP64-Configured" +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. +.SS "Linux with glibc 2.2.5 fails t/op/int subtest #6 with \-Duse64bitint" +.IX Subsection "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 ) +.SS "Linux With Sfio Fails op/misc Test 48" +.IX Subsection "Linux With Sfio Fails op/misc Test 48" +No known fix. +.SS "Mac OS X" +.IX Subsection "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. +.PP +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: +.PP +.Vb 4 +\& 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 +.Ve +.PP +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. +.PP +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). +.PP +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 \fBlocaltime()\fR call is found to be +threadunsafe.) +.SS "Mac OS X dyld undefined symbols" +.IX Subsection "Mac OS X dyld undefined symbols" +If after installing Perl 5.8.0 you are getting warnings about missing +symbols, for example +.PP +.Vb 3 +\& dyld: perl Undefined symbols +\& _perl_sv_2pv +\& _perl_get_sv +.Ve +.PP +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: +.PP +.Vb 2 +\& cd /Library/Perl/darwin/CORE +\& mv libperl.dylib libperlold.dylib +.Ve +.PP +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. +.SS "OS/2 Test Failures" +.IX Subsection "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): +.PP +.Vb 6 +\& ../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 +.Ve +.SS "op/sprintf tests 91, 129, and 130" +.IX Subsection "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. +.PP +Test 91 is known to fail on QNX6 (nto), because \f(CW\*(C`sprintf \*(Aq%e\*(Aq,0\*(C'\fR +incorrectly produces \f(CW0.000000e+0\fR instead of \f(CW0.000000e+00\fR. +.PP +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".) +.SS SCO +.IX Subsection "SCO" +The socketpair tests are known to be unhappy in SCO 3.2v5.0.4: +.PP +.Vb 1 +\& ext/Socket/socketpair.t...............FAILED tests 15\-45 +.Ve +.SS "Solaris 2.5" +.IX Subsection "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. +.SS "Solaris x86 Fails Tests With \-Duse64bitint" +.IX Subsection "Solaris x86 Fails Tests With -Duse64bitint" +The following tests are known to fail in Solaris x86 with Perl +configured to use 64 bit integers: +.PP +.Vb 2 +\& ext/Data/Dumper/t/dumper.............FAILED at test 268 +\& ext/Devel/Peek/Peek..................FAILED at test 7 +.Ve +.SS "SUPER-UX (NEC SX)" +.IX Subsection "SUPER-UX (NEC SX)" +The following tests are known to fail on SUPER-UX: +.PP +.Vb 11 +\& 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 +.Ve +.PP +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. +.SS "Term::ReadKey not working on Win32" +.IX Subsection "Term::ReadKey not working on Win32" +Use Term::ReadKey 2.20 or later. +.SS UNICOS/mk +.IX Subsection "UNICOS/mk" +.IP \(bu 4 +During Configure, the test +.Sp +.Vb 1 +\& Guessing which symbols your C compiler and preprocessor define... +.Ve +.Sp +will probably fail with error messages like +.Sp +.Vb 2 +\& 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. +.Ve +.Sp +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. +.IP \(bu 4 +If building Perl with interpreter threads (ithreads), the +\&\fBgetgrent()\fR, \fBgetgrnam()\fR, and \fBgetgrgid()\fR 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. +.SS UTS +.IX Subsection "UTS" +There are a few known test failures. (\fBNote:\fR the relevant information was +available in \fIREADME.uts\fR until support for UTS was removed in Perl +v5.18.0) +.SS "VOS (Stratus)" +.IX Subsection "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. +.SS VMS +.IX Subsection "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. +.SS Win32 +.IX Subsection "Win32" +In multi-CPU boxes, there are some problems with the I/O buffering: +some output may appear twice. +.SS "XML::Parser not working" +.IX Subsection "XML::Parser not working" +Use XML::Parser 2.31 or later. +.SS "z/OS (OS/390)" +.IX Subsection "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. +.PP +.Vb 10 +\& 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 +.Ve +.PP +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.) +.SS "Unicode Support on EBCDIC Still Spotty" +.IX Subsection "Unicode Support on EBCDIC Still Spotty" +Though mostly working, Unicode support still has problem spots on +EBCDIC platforms. One such known spot are the \f(CW\*(C`\ep{}\*(C'\fR and \f(CW\*(C`\eP{}\*(C'\fR +regular expression constructs for code points less than 256: the +\&\f(CW\*(C`pP\*(C'\fR are testing for Unicode code points, not knowing about EBCDIC. +.SS "Seen In Perl 5.7 But Gone Now" +.IX Subsection "Seen In Perl 5.7 But Gone Now" +\&\f(CW\*(C`Time::Piece\*(C'\fR (previously known as \f(CW\*(C`Time::Object\*(C'\fR) 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. +.PP +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). +.PP +The \f(CW\*(C`PerlIO::Scalar\*(C'\fR and \f(CW\*(C`PerlIO::Via\*(C'\fR (capitalised) were renamed as +\&\f(CW\*(C`PerlIO::scalar\*(C'\fR and \f(CW\*(C`PerlIO::via\*(C'\fR (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 +\&\f(CW\*(C`PerlIO::via::QuotedPrint\*(C'\fR. +.PP +The \f(CW\*(C`threads::shared::queue\*(C'\fR and \f(CW\*(C`threads::shared::semaphore\*(C'\fR were +renamed as \f(CW\*(C`Thread::Queue\*(C'\fR and \f(CW\*(C`Thread::Semaphore\*(C'\fR just before 5.8.0. +The main rationale was to have thread modules to obey normal naming, +\&\f(CW\*(C`Thread::\*(C'\fR (the \f(CW\*(C`threads\*(C'\fR and \f(CW\*(C`threads::shared\*(C'\fR themselves are +more pragma-like, they affect compile-time, so they stay lowercase). +.SH "Reporting Bugs" +.IX Header "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. +.PP +If you believe you have an unreported bug, please run the \fBperlbug\fR +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 \f(CW\*(C`perl \-V\*(C'\fR, will be sent off to perlbug@perl.org to be +analysed by the Perl porting team. +.SH "SEE ALSO" +.IX Header "SEE ALSO" +The \fIChanges\fR file for exhaustive details on what changed. +.PP +The \fIINSTALL\fR file for how to build Perl. +.PP +The \fIREADME\fR file for general stuff. +.PP +The \fIArtistic\fR and \fICopying\fR files for copyright information. +.SH HISTORY +.IX Header "HISTORY" +Written by Jarkko Hietaniemi <\fIjhi@iki.fi\fR>. |