#!/bin/bash
echo "'abc''cde''efg'" | grep -oP ".*'\K[^']+"
echo "'abc''cde''efg'" | awk -F\'\' 'gsub(/^'"'"'+|'"'"'+$/, "", $0) {print $NF}'
echo "'abc''cde''efg" | awk -F\'\' 'gsub(/^'"'"'+|'"'"'+$/, "", $0) {print $NF}'