自己编的一个通讯录系统（简陋了点）[5]

                                read message
                                redo
                        ;;
                        "Exit to the main menu" )
                                menu
                        ;;
                        "Exit to the identify menu" )
                                identify
                        ;;
                        "Quit without save" )
                                exit 0
                        ;;
                        * )     echo -e "This is not a valid choice. Try again:"
                                pick=
                        ;;
                esac
        done
}
 
function check ()
{
        checkperson
        checkmail
        checkphone
        if [ -z "$address" ]; then address="Null"; fi
        if [ -z "$message" ]; then message="Null"; fi
}
 
function identify ()
{
        cat << DATA
        The data you input is on the next:
 
                Name: $name
                E-mail: $mail
                Address: $address
                Phone Number: $phone
                Mobile Phone Number: $mobile
                Other Message: $message
 
        Is it right?[ y or n ]:
DATA
        while read answer
        do
                case $answer in