On Oct 12, 2009, at 5:23 AM, purnima bhandari wrote:
Hi,
I am new to OpenVMS Perl. I know that fork is currently not supported
in the OVMS Perl (perl 5.8.6 on Ia64, VMS 8.3). I am currently trying
to port the Perl script which has fork call and running successfully
in UNIX environment. I saw in the readme documentation that we can use
the vfork/exec instead. But I don't know how to use those in the Perl
script and it is failing with below error.
Below is the script snippet.
Code snippet:
outln("($$) run_service()");
$log->debugln("($$) enter run_service()");
# $pid = fork(); // Original script replaced with vfork below
$pid = vfork();
if($pid == 0) { # we are the child
$SIG{CHLD} = $old_sigchld_hnd;
$SIG{INT} = $old_sigint_hnd;
The error:
(574622047) enter run_service()run_observice calling vfork
Undefined subroutine &main::vfork called at /opt/ovt/bin/ovt.pl line
356.
%SYSTEM-F-ABORT, abort
Please guide me, where I am going wrong?
Not sure what the README in 5.8.6 says (that's a five-year-old release
of Perl), but currently in perlvms.pod we say:
=item fork
While in principle the C<fork> operator could be implemented via
(and with the same rather severe limitations as) the CRTL C<vfork()>
routine, and while some internal support to do just that is in
place, the implementation has never been completed, making C<fork>
currently unavailable. A true kernel C<fork()> is expected in a
future version of VMS, and the pseudo-fork based on interpreter
threads may be available in a future version of Perl on VMS (see
L<perlfork>). In the meantime, use C<system>, backticks, or piped
filehandles to create subprocesses.
---
where the language indicates a bit better that the reference to vfork
is not a reference to a Perl function but rather to the CRTL basis
upon which a fork() in Perl could be (but isn't) implemented. The
last sentence is the important one: use system, backticks, or piped
filehandles. I'll just add that you may also want to look on CPAN for
modules in the IPC::* namespace where there are some convenient
abstractions that have had some effort to work portably.
________________________________________
Craig A. Berry
mailto:craigbe...@mac.com
"... getting out of a sonnet is much more
difficult than getting in."
Brad Leithauser
