Version Comparison using KSH

Question

I'm trying to write a function to compare the versions of the products.

my versions can be XX.XX.XX or xx-xx-xx either it's separated with "." or "-" and number of fields can be different either xx.xx or xx.xx.xx or xx.xx.xx.xx

the versions which im gonna compare will identical in delimiters and with the fields

#!/bin/ksh
set -x

compareVersions ()
{
  typeset    IFS='.'
  typeset -a v1=( $1 )
  typeset -a v2=( $2 )
  typeset    n diff

  for (( n=0; n<4; n+=1 )); do
    diff=$((v1[n]-v2[n]))
    if [ $diff -ne 0 ] ; then
      [ $diff -le 0 ] && echo '-1' || echo '1'
      return
    fi
  done
  echo  '0'
} # ----------  end of function compareVersions  ----------

#compareVersions "6100-09-03" "6100-09-02"
compareVersions "6100.09.03" "6100.09.02"

Please check and give me suggestions

I have tried with the below thing which i have got a other post.. but there is no luck.. hope there should some modification should be done. I have to use across platforms ( linux, solaris, AIX ) so i have preferred KSH, i have idea only in shell scripting though.

Answer 1

Create arrays from version strings, then loop through them comparing elements one by one and return values accordingly. The following example will compare two version strings and returns either 0 (versions are equal), 1 (the first version string is greater) or 2 (the second version string is greater).

#!/bin/ksh

function vertest {
  set -A av1 `echo $1 | sed -e 's/\'$3'/ /g'`
  set -A av2 `echo $2 | sed -e 's/\'$3'/ /g'`

  for (( i=0; i < ${#av1[@]}; i++ )) ; do
    [[ ${av1[$i]} -eq ${av2[$i]} ]] && continue
    [[ ${av1[$i]} -gt ${av2[$i]} ]] && return 1
    [[ ${av1[$i]} -lt ${av2[$i]} ]] && return 2
  done
  return 0
}

v1="2-7-2-1"
v2="1-8-0-1"

vertest $v1 $v2 '-'
exit $?

# end of file.

This example will exit to shell with exit code 1. Should you change $v1 to 1-7-2-1, it will exit to shell with exit code 2. And so on, and so forth.

The separator escaping is not complete, but this works with most reasonable separators like a period (.) and a dash (-). This, as well as parameter checking for the vertest() is left as an exercise for the reader.

Answer 2

When the format of both numbers is equal (leading zero as your example), you can use

compareVersions ()
{
  val1=$(echo $1| tr -d ".-")
  echo ${val1}
  val2=$(echo $2| tr -d ".-")
  echo ${val2}

  if [ ${val1} -gt ${val2} ] ; then
     echo 1
     return
  fi
  if [ ${val1} -eq ${val2} ] ; then
      echo 0
      return
  fi
  echo  '-1'
} # ----------  end of function compareVersions  ----------