Checking a range of RedHat versions in Korn shell script

Question

I have a Korn shell script and the following piece of code works:

if [ $LINUXVER = 7.2 ] || [ $LINUXVER = 7.3 ]; then

But I want to modify the code to make a range that covers 7.2, 7.3, 7.4, etc. I know I need to use something like [0-9], and I have tried a number of things, but nothing works. This script is running on multiple remote servers and not the local server where the script is located.

Any help would be appreciated.

Answer 1

If you are using a relatively recent ksh (ksh93 or a compatible clone) then you can use double parentheses for mathematical expressions. For instance

testver() {
   if (( LINUXVER <= 7.1 || LINUXVER >= 7.4 )); then
      print "Unsupported version $LINUXVER"
   else
      print "Supported version $LINUXVER"
   fi
}

LINUXVER=6.9
testver
LINUXVER=7.2
testver
LINUXVER=8.0
testver

The output of this script is

Unsupported version 6.9
Supported version 7.2
Unsupported version 8.0