=head1 DESCRIPTION
-This document describes various features of Compaq's (formerly Digital's)
-Unix operating system (Tru64) that will affect how Perl version 5
-is compiled and/or runs.
+This document describes various features of HP's (formerly Compaq's,
+formerly Digital's) Unix operating system (Tru64) that will affect
+how Perl version 5 (hereafter just Perl) is configured, compiled
+and/or runs.
=head2 Compiling Perl 5 on Tru64
The recommended compiler to use in Tru64 is the native C compiler.
-The native compiler produces much faster code (the speed difference
-is noticeable: several dozen percentages) and also more correct code:
-if you are considering using the GNU C compiler you should use the
-gcc 2.95.3 since all older gcc releases are known to produce broken
-code when compiling Perl. One manifestation of this brokenness is
-the lib/sdbm test dumping core; another is the op/regexp dumping core
-(depending on the GCC release).
+The native compiler produces much faster code (the speed difference is
+noticeable: several dozen percentages) and also more correct code: if
+you are considering using the GNU C compiler you should use at the
+very least the release of 2.95.3 since all older gcc releases are
+known to produce broken code when compiling Perl. One manifestation
+of this brokenness is the lib/sdbm test dumping core; another is many
+of the op/regexp and op/pat, or ext/Storable tests dumping core
+(the exact pattern of failures depending on the GCC release and
+optimization flags).
=head2 Using Large Files with Perl on Tru64
-In Tru64 Perl is automatically able to use large files, that is, files
-larger than 2 gigabytes, there is no need to use the Configure
--Duselargefiles option as described in INSTALL.
+In Tru64 Perl is automatically able to use large files, that is,
+files larger than 2 gigabytes, there is no need to use the Configure
+-Duselargefiles option as described in INSTALL (though using the option
+is harmless).
=head2 Threaded Perl on Tru64
-To compile Perl to use the old Perl 5.005 threads model, run Configure
-with the -Dusethreads -Duse5005threads options as described in INSTALL.
-This will probably only work in Tru64 4.0 and newer releases, older
-operating releases like 3.2 aren't probably going to work properly
-with threads.
+If you want to use threads, you should primarily use the new Perl
+5.8.0 threads model by running Configure with -Duseithreads.
-Beware: the Perl 5.005 threads model is known to have bugs, for
-example the regular expressions are not thread-safe. The bugs are
-very hard to fix are and therefore the 5.005 threads model is still
-classified as an experimental feature.
+The old Perl 5.005 threads is obsolete, unmaintained, and its use is
+discouraged. If you really want it, run Configure with the
+-Dusethreads -Duse5005threads options as described in INSTALL.
+
+Either thread model is going to work only in Tru64 4.0 and newer
+releases, older operating releases like 3.2 aren't probably going
+to work properly with threads.
=head2 Long Doubles on Tru64
You cannot Configure Perl to use long doubles unless you have at least
-Tru64 V5.0, the long double support simply wasn't functional before
-that.
+Tru64 V5.0, the long double support simply wasn't functional enough
+before that. Perl's Configure will override attempts to use the long
+doubles (you can notice this by Configure finding out that the modfl()
+function does not work as it should).
+
+At the time of this writing (June 2002), there is a known bug in the
+Tru64 libc printing of long doubles when not using "e" notation.
+The values are correct and usable, but you only get a limited number
+of digits displayed unless you force the issue by using C<printf
+"%.33e",$num> or the like. For Tru64 versions V5.0A through V5.1A, a
+patch is expected sometime after perl 5.8.0 is released. If your libc
+has not yet been patched, you'll get a warning from Configure when
+selecting long doubles.
=head2 64-bit Perl on Tru64
In Tru64 Perl's integers are automatically 64-bit wide, there is
no need to use the Configure -Duse64bitint option as described
-in INSTALL. Similarly, there is no need for -Duse64bitall.
+in INSTALL. Similarly, there is no need for -Duse64bitall
+since pointers are automatically 64-bit wide.
=head2 Warnings about floating-point overflow when compiling Perl on Tru64
return HUGE_VAL;
-----------^
- cc: Warning: POSIX.xs, line 1304: In this statement, floating-point overflow occurs in evaluating the expression "1.8e308". (floatoverfl)
+and when compiling the POSIX extension
+
+ cc: Warning: const-c.inc, line 2007: In this statement, floating-point overflow occurs in evaluating the expression "1.8e308". (floatoverfl)
return HUGE_VAL;
-------------------^
-The exact line numbers may vary between Perl releases.
-The warnings are benign and can be ignored.
+The exact line numbers may vary between Perl releases. The warnings
+are benign and can be ignored: in later C compiler releases the warnings
+should be gone.
When the file F<pp_sys.c> is being compiled you may (depending on the
operating system release) see an additional compiler flag being used:
cannot be tested before Perl has been installed. The test refers to
the use of the C<-P> option of Perl.
+=head1 ext/ODBM_File/odbm Test Failing With Static Builds
+
+The ext/ODBM_File/odbm is known to fail with static builds
+(Configure -Uusedl) due to a known bug in Tru64's static libdbm
+library. The good news is that you very probably don't need to ever
+use the ODBM_File extension since more advanced NDBM_File works fine,
+not to mention the even more advanced DB_File.
+
+=head1 Perl Fails Because Of Unresolved Symbol sockatmark
+
+If you get an error like
+
+ Can't load '.../OSF1/lib/perl5/5.8.0/alpha-dec_osf/auto/IO/IO.so' for module IO: Unresolved symbol in .../lib/perl5/5.8.0/alpha-dec_osf/auto/IO/IO.so: sockatmark at .../lib/perl5/5.8.0/alpha-dec_osf/XSLoader.pm line 75.
+
+you need to either recompile your Perl in Tru64 4.0D or upgrade your
+Tru64 4.0D to at least 4.0F: the sockatmark() system call was
+added in Tru64 4.0F, and the IO extension refers that symbol.
+
=head1 AUTHOR
Jarkko Hietaniemi <jhi@iki.fi>