Tuesday, November 2, 2021

[SOLVED] Checking a range of RedHat versions in Korn shell script

Issue

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.


Solution

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


Answered By - Paul Floyd
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