1 

     2 result="$4"

     3 

     4 case "$1" in

     5   *c*) ./compile $2.c >/dev/null 2>&1 || result="$3" ;;

     6 esac

     7 

     8 case "$1" in

     9   *l*) ./load $2 >/dev/null 2>&1 || result="$3" ;;

    10 esac

    11 

    12 case "$1" in

    13   *r*) ./$2 >/dev/null 2>&1 || result="$3" ;;

    14 esac

    15 

    16 rm -f $2.o $2

    17 

    18 exec cat "$result"