shell script to create a user account on linux

createAccount.sh

#!/bin/bash

clear

trap "" SIGHUP SIGINT SIGTERM SIGTSTP

#get username, check if its taken, and if its proper length
while true
do
	echo -n "Create username: "
	read username
	if [ ${#username} -gt 0 ]
	then
		if [ $(cat /etc/passwd | grep $username) ]
		then
			echo "Username already exists. Please choose another one."
		elif [ ${#username} -gt 2 ] && [ ${#username} -lt 10 ]
		then
			break
		else
			echo "Username must be between 2 to 10 characters."
		fi
	else
		echo "Username can not be blank."
	fi

done

#get passwords and check if they're the same
while true
do
	echo -n "Password: "
	read password
	echo -n "Confirm password: "
	read password_confirm
	if [ ${#password} -gt 0 ] || [ ${#password_confirm} -gt 0 ]
	then
		if [ $password == $password_confirm ]
		then
			break
		else
			echo "Passwords do not match."
		fi
	else
		echo "Password can not be blank."
	fi
done

#add user
useradd $username -m -s /bin/bash -G users

#give user password
echo $username:$password | chpasswd

echo "Account created! Please login to your new account."

kill -HUP $PPID