Very nice...thank you it is what I needed.
This is running on HPUX and the one I found that works is the following: 
$tpgrp = tcgetpgrp(fileno(*TTY));
$pgrp = getpgrp();
if ($tpgrp == $pgrp) {
    system("which which > whichtest");
} else {
    print "Skipping which as we are not interactive.\n";
}

[download]
I needed a change in this as the system call on HPUX gets the shell into a waiting state until it receives some input, which does not work well if we run it as a background process. Rather than skip doing this as a check, which we could do as the script is run manually at times, I wanted a way to have it run only when we needed it.

In reply to Re^2: Is Process Running In The Background? by gokuraku
in thread Is Process Running In The Background? by gokuraku

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