#!/bin/bash packages=$1 echo -n "* Validating action arguments... "; if [ "$packages" == "" ]; then echo "aborted." echo "* Packages argument cannot be empty." >&2 exit 1 fi for package in $packages; do apt-cache search ^$package$ | grep $package > /dev/null if [ $? -ne 0 ]; then echo "aborted." echo "* Package '$package' not found." >&2 exit 2 fi done echo "done."