Bash shell脚本从文件中删除文件/查找文件中的文本

Question

我是Bash的新手，并且想知道是否有人可以让我了解如何让这个程序更准确地运作。

目标：编写一个bash shell脚本，向用户显示一个菜单，其中包含添加联系人，删除联系人，查找联系人，列出所有联系人以及退出程序的选项。

到目前为止，这是我的代码：

#!/bin/bash
touch contacts.dat
echo "Select one of the following options:"
echo "-------------------------------------"
echo "1. Add a contact"
echo "2. Remove a contact"
echo "3. Find a contact"
echo "4. List all contacts"
echo "5. Exit the program"
read -p "Enter a choice (1-5): " choice
echo
#
case "$choice" in
    1)
    read -p "Enter a name: " name
    read -p "Enter an email address: " email
    echo "$name , $email" >> contacts.dat
    ;;
2)
    read -p "Enter a name: " name
    if (grep -q name contacts.dat) then
        grep -v name contacts.dat > deletedNames.dat
        echo "$name was removed from the file."
    else
        echo "$name does not exist in the file."
    fi
    ;;
3)
    read -p "Enter a name: " name
    if (grep -q name contacts.dat) then
        echo "$name , $email"
    else
        echo "The $name was not found."
    fi
    ;;
4)
    sort -k 1 contacts.dat 
    ;; 
5)
    echo "Thank you for using this program!"
    # break?
    exit 1
    ;;
*)
    echo "Please enter a valid choice (1-5)."
    ;;
esac

该程序似乎适用于选项1,4和5.但是，不是2和3。

如何获得2和3删除联系人并找到联系人（尊敬地）？提前感谢您提供的任何帮助。