Simple Script to create a user on centos 6.5

Default passwd is set as username@123 As we are setting the chage, user needs to change the passwd on first login.

usage() {
  echo -e "
usage: $0 <single-parameter>
  Optional parameters:\n
	 --sudo-user, -s\t\tCreate a sudo User
	 --norm-user, -n\t\tCreate a Normal User.
	 --help,      -h\t\tDisplay this Message.
  "
  exit 1
}

create_normal_user()
{
	USRNAME=$1
	#  create user
	useradd $USRNAME
	echo ${USRNAME}@123 | passwd ${USRNAME} --stdin
	
	#  make sure user changes his passwd on first login
	chage -d 0 ${USRNAME}
}

create_sudo_user()
{
	SUDO_USRNAME=$1
	create_normal_user ${SUDO_USRNAME}
	echo -e "${SUDO_USRNAME}\tALL=(ALL)\tALL" >> /etc/sudoers
}

while true ; do
  case "$1" in
	-s)
	  create_sudo_user $2
	  exit 1
	  ;;
	-n)
	  create_normal_user $2
	  exit 1
	  ;;
	--sudo-user)
	  create_sudo_user $2
	  exit 1
	  ;;
	--norm-user)
	  create_normal_user $2
	  exit 1
	  ;;
	-h)
	  usage
	  exit 1
	  ;;
	--help)
	  usage
	  exit 1 
	  ;;
	*)
	  echo "Unknown option: $1"
	  usage
	  exit 1
	esac
done