#!/bin/bash

function yes_no_abort {
        echo "hi"
    local yn
    while true; do
        read -r -p "[y/n/a]: " yn
        case $yn in
            [Yy]) echo "0"; return 0  ;;
            [Nn]) echo "1"; return 1 ;;
            [Aa]) echo "2"; return 2 ;;
        esac
    done
}

echo "Continue? "
res=$(yes_no_abort)
if [ $res == 0 ]; then echo "answered yes"; exit 0; fi;
if [ $res == 1 ]; then echo "answered no"; exit 1; fi;
if [ $res == 2 ]; then echo "answered abort"; exit 2; fi;