I think the explanation moritz gives above is right. Should you need a workaround, you can probably send the entire process group a signal (other than KILL, obviously) after putting a handler in to ignore that signal in the parent.

Warning: drylabbed code ahead. Not tested, though I do have a little experience using signals in Perl. 


my $pgrp_id=getpgrp(0) # gets the process group id of
                       # the current process

{ # scoping is important!  Otherwise
  # that signal will always be ignored
  # by the parent, which is probably bad.
  # I picked SIGINT, you might prefer something
  # else.

    local $SIG{'INT'}='IGNORE'; 
    kill 2, -$pgrp_id; # - means it's a group id.
}

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But, of course, this assumes you don't have other stuff running in the process group that you need to leave alive, besides the parent.

This does raise the question of why you need to kill it via a signal, of course.

In reply to Re: exec sometimes changes pid by ssandv
in thread exec sometimes changes pid by doom

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