Shell Programming and Scripting

./script cat "-u" cat "-u" inputfile

#!/bin/bash
#
usage() { 		#print usage message and quit
	echo "Usage: program1 [program1 options] program2 [program2 options] [inputfilelist]"
	exit 1
}

program1=${1}
program2=${3}
program1setting=${2}
program2setting=${4}

if [ -x ${1} ]; then
	echo "program 1 exist"
else
	echo "first program does not exist"
	usage
fi

if [ -x ${3} ]; then
	echo "program 2 exist"
else
	echo "second program does not exist"
	usage
fi

if [ -x "`which ${1}`" ]; then