PT - Trace process ID up in the process tree

pt

#! /bin/sh

# PT - Trace process ID up in the process tree
# Copyright (C) 2012 Matous J. Fialka, <http://mjf.cz/>
# Released under the terms of The MIT License

if [ $# -ne 1 ]
then
	echo usage: pt pid
	exit
fi

if [ $1 -lt 1 ]
then
	exit
fi

if ps -o pid= -p $1
then
	$0 `ps -o ppid= -p $1`
fi