Then the code I gave you should already work and kill the child at the end of the program. Maybe closing the filehandle to the kid and also adding a call to kill outside the END block helps to kill the kid earlier.

Okay, I tried that - closing the filehandle and putting the kill at the end of the script - still no go. Perl program stops executing until I exit the java app. It just does not seem that open() is launching the process in the background.

The following code behaves just like it should (and like I said) for me:

corion@aliens:~/tmp$ cat test.pl
#!perl -w
use strict;

my $pid = open my $fh, 'sleep 1000 |'
    or die "Couldn't spawn: $! / $?";

print "Spawned child as $pid";
print "Doing own work $_\n" for 1..10;

print "Killing child $pid";
kill 9 => $pid;
print "done\n";
[download]

corion@aliens:~/tmp$ perl -w test.pl
Spawned child as 26868Doing own work 1
Doing own work 2
Doing own work 3
Doing own work 4
Doing own work 5
Doing own work 6
Doing own work 7
Doing own work 8
Doing own work 9
Doing own work 10
Killing child 26868done
[download]

I'm not sure what you're doing differently.