You're executing command in the background, so the pid you are getting back is the pid of the shell that's spawning command and not of command itself. Just want to make sure you're aware of that.

If you just want to launch command and not worry about it, just use fork and exec directly: 

my $pid = fork();
die "unable to fork: $!" unless defined($pid);
if (!$pid) {  # child
    exec('command...');
    die "unable to exec: $!";
}
# parent continues here, pid of child is in $pid

[download]

In the exec, perhaps you'll want to redirect the child's output to either /dev/null or a file.

Another option is to 'daemonize' the child which involves detaching it from the parent's process group. For an example, have a look at http://snippets.dzone.com/posts/show/359, and I'm sure there's code on CPAN to do it, too.

In your original code, I think you were getting broken pipes because you were closing $handle and the child was still writing to its STDOUT.

In reply to Re: Launch process, get PID by pc88mxer
in thread Launch process, get PID by rvosa

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