(?p{}) has been deprecated for a long time.
[p5sagit/p5-mst-13.2.git] / README.tru64
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ea3bceb2 1If you read this file _as_is_, just ignore the funny characters you see.
2It is written in the POD format (see pod/perlpod.pod) which is specially
3designed to be readable as is.
4
5=head1 NAME
6
7README.tru64 - Perl version 5 on Tru64 (formerly known as Digital UNIX formerly known as DEC OSF/1) systems
8
9=head1 DESCRIPTION
10
88ec1f5d 11This document describes various features of HP's (formerly Compaq's,
12formerly Digital's) Unix operating system (Tru64) that will affect
92c48b5b 13how Perl version 5 (hereafter just Perl) is configured, compiled
14and/or runs.
ea3bceb2 15
16=head2 Compiling Perl 5 on Tru64
17
18The recommended compiler to use in Tru64 is the native C compiler.
88ec1f5d 19The native compiler produces much faster code (the speed difference is
20noticeable: several dozen percentages) and also more correct code: if
92c48b5b 21you are considering using the GNU C compiler you should use at the
22very least the release of 2.95.3 since all older gcc releases are
23known to produce broken code when compiling Perl. One manifestation
24of this brokenness is the lib/sdbm test dumping core; another is many
25of the op/regexp and op/pat, or ext/Storable tests dumping core
26(the exact pattern of failures depending on the GCC release and
27optimization flags).
ea3bceb2 28
532eb838 29gcc 3.2.1 is known to work okay with Perl 5.8.0. However, when
30optimizing the toke.c gcc likes to have a lot of memory, 256 megabytes
31seems to be enough. The default setting of the process data section
32in Tru64 should be one gigabyte, but some sites/setups might have
33lowered that. The configuration process of Perl checks for too low
34process limits, and lowers the optimization for the toke.c if
35necessary, and also gives advice on how to raise the process limits.
36
ea3bceb2 37=head2 Using Large Files with Perl on Tru64
38
88ec1f5d 39In Tru64 Perl is automatically able to use large files, that is,
40files larger than 2 gigabytes, there is no need to use the Configure
92c48b5b 41-Duselargefiles option as described in INSTALL (though using the option
42is harmless).
ea3bceb2 43
44=head2 Threaded Perl on Tru64
45
294f22c5 46If you want to use threads, you should primarily use the Perl
88ec1f5d 475.8.0 threads model by running Configure with -Duseithreads.
ea3bceb2 48
294f22c5 49Perl threading is going to work only in Tru64 4.0 and newer releases,
50older operating releases like 3.2 aren't probably going to work
51properly with threads.
ea3bceb2 52
700a71f5 53In Tru64 V5 (at least V5.1A, V5.1B) you cannot build threaded Perl with gcc
54because the system header <pthread.h> explicitly checks for supported
55C compilers, gcc (at least 3.2.2) not being one of them. But the
56system C compiler should work just fine.
57
bef5f079 58=head2 Long Doubles on Tru64
59
92c48b5b 60You cannot Configure Perl to use long doubles unless you have at least
61Tru64 V5.0, the long double support simply wasn't functional enough
62before that. Perl's Configure will override attempts to use the long
63doubles (you can notice this by Configure finding out that the modfl()
64function does not work as it should).
bef5f079 65
88ec1f5d 66At the time of this writing (June 2002), there is a known bug in the
67Tru64 libc printing of long doubles when not using "e" notation.
68The values are correct and usable, but you only get a limited number
69of digits displayed unless you force the issue by using C<printf
70"%.33e",$num> or the like. For Tru64 versions V5.0A through V5.1A, a
71patch is expected sometime after perl 5.8.0 is released. If your libc
72has not yet been patched, you'll get a warning from Configure when
73selecting long doubles.
fa17d112 74
7db3d8c1 75=head2 DB_File tests failing on Tru64
76
77The DB_File tests (db-btree.t, db-hash.t, db-recno.t) may fail you
78have installed a newer version of Berkeley DB into the system and the
7f274f0f 79-I and -L compiler and linker flags introduce version conflicts with
80the DB 1.85 headers and libraries that came with the Tru64. For example,
81mixing a DB v2 library with the DB v1 headers is a bad idea. Watch
82out for Configure options -Dlocincpth and -Dloclibpth, and check your
83/usr/local/include and /usr/local/lib since they are included by default.
7db3d8c1 84
85The second option is to explicitly instruct Configure to detect the
86newer Berkeley DB installation, by supplying the right directories with
87C<-Dlocincpth=/some/include> and C<-Dloclibpth=/some/lib> B<and> before
88running "make test" setting your LD_LIBRARY_PATH to F</some/lib>.
89
90The third option is to work around the problem by disabling the
91DB_File completely when build Perl by specifying -Ui_db to Configure,
7f274f0f 92and then using the BerkeleyDB module from CPAN instead of DB_File.
93The BerkeleyDB works with Berkeley DB versions 2.* or greater.
7db3d8c1 94
95The Berkeley DB 4.1.25 has been tested with Tru64 V5.1A and found
cfc8a802 96to work. The latest Berkeley DB can be found from F<http://www.sleepycat.com>.
97
ea3bceb2 98=head2 64-bit Perl on Tru64
99
100In Tru64 Perl's integers are automatically 64-bit wide, there is
101no need to use the Configure -Duse64bitint option as described
88ec1f5d 102in INSTALL. Similarly, there is no need for -Duse64bitall
103since pointers are automatically 64-bit wide.
ea3bceb2 104
105=head2 Warnings about floating-point overflow when compiling Perl on Tru64
106
107When compiling Perl in Tru64 you may (depending on the compiler
108release) see two warnings like this
109
d780cd7a 110 cc: Warning: numeric.c, line 104: In this statement, floating-point overflow occurs in evaluating the expression "1.8e308". (floatoverfl)
ea3bceb2 111 return HUGE_VAL;
112 -----------^
113
ef3337d4 114and when compiling the POSIX extension
115
116 cc: Warning: const-c.inc, line 2007: In this statement, floating-point overflow occurs in evaluating the expression "1.8e308". (floatoverfl)
ea3bceb2 117 return HUGE_VAL;
118 -------------------^
119
92c48b5b 120The exact line numbers may vary between Perl releases. The warnings
121are benign and can be ignored: in later C compiler releases the warnings
122should be gone.
ea3bceb2 123
124When the file F<pp_sys.c> is being compiled you may (depending on the
125operating system release) see an additional compiler flag being used:
126C<-DNO_EFF_ONLY_OK>. This is normal and refers to a feature that is
127relevant only if you use the C<filetest> pragma. In older releases of
128the operating system the feature was broken and the NO_EFF_ONLY_OK
129instructs Perl not to use the feature.
130
131=head1 Testing Perl on Tru64
132
133During "make test" the C<comp/cpp> will be skipped because on Tru64 it
134cannot be tested before Perl has been installed. The test refers to
135the use of the C<-P> option of Perl.
136
2dfde39d 137=head1 ext/ODBM_File/odbm Test Failing With Static Builds
138
139The ext/ODBM_File/odbm is known to fail with static builds
88ec1f5d 140(Configure -Uusedl) due to a known bug in Tru64's static libdbm
2dfde39d 141library. The good news is that you very probably don't need to ever
142use the ODBM_File extension since more advanced NDBM_File works fine,
143not to mention the even more advanced DB_File.
144
9a8de003 145=head1 Perl Fails Because Of Unresolved Symbol sockatmark
146
147If you get an error like
148
4282de36 149 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.
9a8de003 150
151you need to either recompile your Perl in Tru64 4.0D or upgrade your
92c48b5b 152Tru64 4.0D to at least 4.0F: the sockatmark() system call was
153added in Tru64 4.0F, and the IO extension refers that symbol.
9a8de003 154
ea3bceb2 155=head1 AUTHOR
156
157Jarkko Hietaniemi <jhi@iki.fi>
158
159=cut