#!/bin/bash # hypotenuse.sh: Returns the "hypotenuse" of a right triangle. # (square root of sum of squares of the "legs") ARGS=2 # Script needs sides of triangle passed. E_BADARGS=65 # Wrong number of arguments. if [ $# -ne "$ARGS" ] # Test number of arguments to script. then echo "Usage: `basename $0` side_1 side_2" exit $E_BADARGS fi AWKSCRIPT=' { printf( "%3.7f\n", sqrt($1*$1 + $2*$2) ) } ' # command(s) / parameters passed to awk # Now, pipe the parameters to awk. echo -n "Hypotenuse of $1 and $2 = " echo $1 $2 | awk "$AWKSCRIPT" # ^^^^^^^^^^^^ # An echo-and-pipe is an easy way of passing shell parameters to awk. exit 0 # Exercise: Rewrite this script using 'bc' rather than awk. # Which method is more intuitive?