#!/bin/sh function _diffab(){ x=0 for i in `cat $1`;do for j in `cat $2`;do if [ $i == $j ];then x=1 break; fi done if [ $x -ne 1 ];then echo $i fi x=0 done }
if [ "$1" == "" ] || [ "$2" == "" ];then echo "use like this: $0 filea fileb" else { _diffab $1 $2 _diffab $2 $1 } fi
