# $Id: Head.U,v 3.0.1.9 1997/02/28 15:02:09 ram Exp $
#
-# Generated on Tue Mar 19 18:17:12 EET 2002 [metaconfig 3.0 PL70]
+# Generated on Wed Mar 20 05:22:55 EET 2002 [metaconfig 3.0 PL70]
# (with additional metaconfig patches by perlbug@perl.org)
cat >c1$$ <<EOF
$define)
$cat <<EOM
-As of 5.5.640, Perl has two different internal threading implementations,
-the 5.005 version (5005threads) and an interpreter-based version
-(ithreads) that has one interpreter per thread. Both are very
-experimental. This arrangement exists to help developers work out
-which one is better.
+As of release 5.6, Perl has two different threading implementations,
+an interpreter-based version (ithreads) with one interpreter per
+thread, and the 5.005 version (5005threads). Both implementations
+are considered experimental, but since 5.8 ithreads somewhat less so.
+The 5005threads is effectively unmaintained.
-If you're a casual user, you probably don't want interpreter-threads
-at this time. But if you do, the 'threads' module allows their use,
-and the 'Thread' module offers an interface to both 5005threads and
-ithreads (whichever has been configured).
EOM
: Default to ithreads unless overridden on command line or with
: old config.sh
The default is to compile without thread support.
-As of v5.5.64, perl has two different internal threads implementations.
-The 5.005 version (5005threads) and an interpreter-based implementation
-(ithreads) with one interpreter per thread. By default, Configure selects
-ithreads if -Dusethreads is specified. However, you can select the old
-5005threads behavior instead by either
+Perl has two different internal threads implementations. The current
+model (available internally since 5.6, and as a user-level module
+since 5.8) is called interpreter-based implementation (ithreads),
+with one interpreter per thread, and explicit sharing of data.
- sh Configure -Dusethreads -Duse5005threads
+The 5.005 version (5005threads) is considered obsolete, buggy, and
+unmaintained.
+
+By default, Configure selects ithreads if -Dusethreads is specified.
-or by
- sh Configure -Dusethreads -Uuseithreads
+However, you can select the old 5005threads behavior
-Eventually (by perl v5.6.0) this internal confusion ought to disappear,
-and these options may disappear as well.
+ sh Configure -Dusethreads -Duse5005threads
+
+If you decide to use ithreads, the 'threads' module allows their use,
+and the 'Thread' module offers an interface to both 5005threads and
+ithreads (whichever has been configured).
=head2 Large file support.
=head2 Selecting File IO mechanisms
Previous versions of perl used the standard IO mechanisms as defined in
-stdio.h. Versions 5.003_02 and later of perl allow alternate IO
+stdio.h. Versions 5.003_02 and later of perl allowed alternate IO
mechanisms via a "PerlIO" abstraction, but the stdio mechanism is still
the default and is the only supported mechanism.
-This PerlIO abstraction can be enabled either on the Configure command
-line with
+Starting from Perl 5.8 the default mechanism is to use the PerlIO
+abstraction, because it allows better control of I/O mechanisms,
+instead of having to work with (often, work around) vendors' I/O
+implementations.
- sh Configure -Duseperlio
+This PerlIO abstraction can be disabled either on the Configure
+command line with
-or interactively at the appropriate Configure prompt.
+ sh Configure -Uuseperlio
-If you choose to use the PerlIO abstraction layer, there are two
-(experimental) possibilities for the underlying IO calls. These have been
-tested to some extent on some platforms, but are not guaranteed to work
-everywhere.
-
-=over 4
-
-=item 1.
+or interactively at the appropriate Configure prompt.
-AT&T's "sfio". This has superior performance to stdio.h in many
-cases, and is extensible by the use of "discipline" modules. Sfio
-currently only builds on a subset of the UNIX platforms perl supports.
-Because the data structures are completely different from stdio, perl
-extension modules or external libraries may not work. This
-configuration exists to allow these issues to be worked on.
+With the PerlIO abstraction layer, there is another possibility for
+the underlying IO calls, AT&T's "sfio". This has superior performance
+to stdio.h in many cases, and is extensible by the use of "discipline"
+modules ("Native" PerlIO has them too). Sfio currently only builds on
+a subset of the UNIX platforms perl supports. Because the data
+structures are completely different from stdio, perl extension modules
+or external libraries may not work. This configuration exists to
+allow these issues to be worked on.
This option requires the 'sfio' package to have been built and installed.
The latest sfio is available from http://www.research.att.com/sw/tools/sfio/
_exit vs. exit. If you have this problem, the fix is to go back to
your sfio sources and correct iffe's guess about atexit.
-=item 2.
-
-Normal stdio IO, but with all IO going through calls to the PerlIO
-abstraction layer. This configuration can be used to check that perl and
-extension modules have been correctly converted to use the PerlIO
-abstraction.
-
-This configuration should work on all platforms (but might not).
-
-You select this option via:
-
- sh Configure -Duseperlio -Uusesfio
-
-If you have already selected -Duseperlio, and if Configure does not
-detect sfio, then this will be the default suggested by Configure.
-
-=back
-
=head2 SOCKS
Perl can be configured to be 'socksified', that is, to use the SOCKS
https://perl5.git.perl.org / perl5.git / commitdiff