Bash function to generate a simple, random, but pronouncable username

random_username.sh

function generate_username {
    # Generate a simple, random, but pronouncable username
    username=""
    for i in {1..4}; do
        if [[ $((i%2)) == 0 ]]; then
            charset="aeiou"
        else
            charset="bcdfghjklmnpqrstvwxyz"
        fi
        username="$username$(tr -dc "$charset" < /dev/urandom | head -c 1)"
    done
    username="$username$(tr -dc "0-9" < /dev/urandom | head -c 2)"
    echo "$username"
}