if [ ! -r "$1" ]; then echo "Cannot read file indicated by first argument '$1'." ; exit -1 ; fi ; if [ ! -r "$2" ];then echo "Cannot read file indicated by second argument '$1'." ; exit -1 ; fi ; if [ ! -x /usr/bin/bc ]; then echo "The bc tool is not installed as /usr/bin/bc, if installed at all." ; exit -1 ; fi ; a=$(cat $1|tr -d '\n') ; b=$(cat $2|tr -d '\n') ; echo "$a+$b" | bc | tr -d '\n'