UNIX for Dummies Questions & Answers

#!/bin/ksh
# compare version numbers
# usage: vercmp <versionnr1> <versionnr2>
#         with format for versions xxx.xxx.xxx
# returns: 0 if versionnr1 equal or greater
#          1 if versionnr1 lower
vercmp()
{
        IFS=.
        echo "$1" |read a1 b1 c1
        echo "$2" |read a2 b2 c2
        IFS=" "
        ret=$(((a1 - a2) * 1000000 + (b1 - b2) * 1000 + c1 - c2))
        test $ret -gt -1
        return $?
}

vercmp 9.2.5 10.3.9
echo $?
vercmp 10.3.2 9.1.1
echo $?
vercmp 10.3.2 9.9.9
echo $?
vercmp 10.3.2 10.3.2
echo $?