Here's an example:

#!/bin/bash
IP=192.168.11.1
function split()
{
  export IPARRAY
  IFS='.' read -ra IPARRAY < << "$1"
  for i in "${IPARRAY[@]}"; do
      echo process "$i"
  done
}

split $IP
echo ${IPARRAY[*]}
echo ${IPARRAY[0]}

Output:


process 192
process 168
process 11
process 1
192 168 11 1
192