Bash read line loop

read lines.sh

#!/bin/bash
historyDir=/tmp/historyTest

function handle() {
    echo "now run '$1'"
}

function cleanup() {
    history -w $historyDir/$UID
}
function ctrl_c() {
    echo
    cleanup
    exit 1
}

trap ctrl_c INT

mkdir -p $historyDir
history -r $historyDir/$UID

set -o vi
cmd=""
while true; do
    read -p '> ' -e cmd
    history -s "$cmd"
    case "$cmd" in
        exit) cleanup; exit 0; ;;
        history) history; ;;
        *) handle "$cmd"; ;;
    esac
done