If I understand your question correctly, you basically want to fork a number of child processes and then either wait for them or set a signal handler while you do something useful. The Perl Cookbook has lots of example code for this, as has this site. In pseudocode, you would:

@children[0]=sub{ child_1_code };
@children[1]=sub{ child_2_code };
@children[2]=sub{ child_3_code };
foreach $child @children {
  spawn( $child);
}
while (($returned_child = wait()) > 0 ) {
  print "Child $returned_child has finished";
}

sub spawn {
  $code=shift;
  die "Something fishy: $!\n" if (($ret=fork()) == -1);
  return if $ret;
  exit &$code;
}
[download]

Being something halfway between pseudocode and real code, this has not been tested and will definitely not work as written.

CU
Robartes-