I just caught your third example there - and it works also: 
$kid = open (FH, "exec java JavaApp 2> /dev/null |");

[download]
So then instead of the shell running the app, the shell becomes the app, so the pid is the same. clever.

In reply to Re^4: how to kill background process when script exit? by Allasso
in thread how to kill background process when script exit? by Allasso

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