NAME

       perltru64 - Perl version 5 on Tru64 (formerly known as Digital UNIX formerly known as DEC
       OSF/1) systems

DESCRIPTION

       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.

   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
       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).

       gcc 3.2.1 is known to work okay with Perl 5.8.0.  However, when optimizing the toke.c gcc
       likes to have a lot of memory, 256 megabytes seems to be enough.  The default setting of
       the process data section in Tru64 should be one gigabyte, but some sites/setups might have
       lowered that.  The configuration process of Perl checks for too low process limits, and
       lowers the optimization for the toke.c if necessary, and also gives advice on how to raise
       the process limits.

       Also, Configure might abort with

           Build a threading Perl? [n]
           Configure[2437]: Syntax error at line 1 : 'config.sh' is not expected.

       This indicates that Configure is being run with a broken Korn shell (even though you think
       you are using a Bourne shell by using "sh Configure" or "./Configure").  The Korn shell
       bug has been reported to Compaq as of February 1999 but in the meanwhile, the reason ksh
       is being used is that you have the environment variable BIN_SH set to 'xpg4'.  This causes
       /bin/sh to delegate its duties to /bin/posix/sh (a ksh).  Unset the environment variable
       and rerun Configure.

   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 (though using the option is harmless).

   Threaded Perl on Tru64
       If you want to use threads, you should primarily use the Perl 5.8.0 threads model by
       running Configure with -Duseithreads.

       Perl threading 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.

       In Tru64 V5 (at least V5.1A, V5.1B) you cannot build threaded Perl with gcc because the
       system header <pthread.h> explicitly checks for supported C compilers, gcc (at least
       3.2.2) not being one of them.  But the system C compiler should work just fine.

   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 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 "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.

   DB_File tests failing on Tru64
       The DB_File tests (db-btree.t, db-hash.t, db-recno.t) may fail you have installed a newer
       version of Berkeley DB into the system and the -I and -L compiler and linker flags
       introduce version conflicts with the DB 1.85 headers and libraries that came with the
       Tru64.  For example, mixing a DB v2 library with the DB v1 headers is a bad idea.  Watch
       out for Configure options -Dlocincpth and -Dloclibpth, and check your /usr/local/include
       and /usr/local/lib since they are included by default.

       The second option is to explicitly instruct Configure to detect the newer Berkeley DB
       installation, by supplying the right directories with "-Dlocincpth=/some/include" and
       "-Dloclibpth=/some/lib" and before running "make test" setting your LD_LIBRARY_PATH to
       /some/lib.

       The third option is to work around the problem by disabling the DB_File completely when
       build Perl by specifying -Ui_db to Configure, and then using the BerkeleyDB module from
       CPAN instead of DB_File.  The BerkeleyDB works with Berkeley DB versions 2.* or greater.

       The Berkeley DB 4.1.25 has been tested with Tru64 V5.1A and found to work.  The latest
       Berkeley DB can be found from <http://www.sleepycat.com>.

   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 since pointers are automatically 64-bit wide.

   Warnings about floating-point overflow when compiling Perl on Tru64
       When compiling Perl in Tru64 you may (depending on the compiler release) see two warnings
       like this

           cc: Warning: numeric.c, line 104: In this statement, floating-point overflow occurs in evaluating the expression "1.8e308". (floatoverfl)
               return HUGE_VAL;
           -----------^

       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: in later C compiler releases the warnings should be gone.

       When the file pp_sys.c is being compiled you may (depending on the operating system
       release) see an additional compiler flag being used: "-DNO_EFF_ONLY_OK".  This is normal
       and refers to a feature that is relevant only if you use the "filetest" pragma.  In older
       releases of the operating system the feature was broken and the NO_EFF_ONLY_OK instructs
       Perl not to use the feature.

Testing Perl on Tru64

       During "make test" the "comp/cpp" will be skipped because on Tru64 it cannot be tested
       before Perl has been installed.  The test refers to the use of the "-P" option of Perl.

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.

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.

AUTHOR

       Jarkko Hietaniemi <jhi@iki.fi>