Shell script -select in loop

select in yes Shell A unique cycle

Usage is as follows ：

select variable in value_list
do
    statements
done

variable Said variable ,value_list Indicates the value list ,in yes Shell Keywords in .

Code 1

#!/bin/bash
echo "What is your favourite OS?"
select name in "Linux" "Windows" "Mac OS" "UNIX" "Android"
do
    echo "You have selected $name"
done

The running script is shown below ：

What is your favourite OS?
1) Linux
2) Windows
3) Mac OS
4) UNIX
5) Android
#?

 The input numbers are displayed as follows ：
#? 3
You have selected Mac OS
#? 4
You have selected UNIX
#? 7
You have selected
#?

 Input Ctrl+D  Composite key , sign out 

Be careful ,select It's infinite circulation （ Dead cycle ）, Enter a null value , Or the value entered is invalid , Will not end the cycle , Only meet break sentence , Or press Ctrl+D Key combination can end the cycle .

Code 2：select in Usually and case in Use it together

#!/bin/bash
echo "What is your favourite OS?"
select name in "Linux" "Windows" "Mac OS" "UNIX" "Android"
do
    case $name in
        "Linux")
            echo "Linux Is a class UNIX operating system , It's open source and free , Run on various server devices and embedded devices ."
            break
            ;;
        "Windows")
            echo "Windows It's a personal computer operating system developed by Microsoft , It's closed source charging ."
            break
            ;;
        "Mac OS")
            echo "Mac OS Apple is based on UNIX Developed a graphical interface operating system , It can only run on the hardware provided by Apple ."
            break
            ;;
        "UNIX")
            echo "UNIX Is the founder of the operating system , Now it has gradually withdrawn from the stage of history , Only for special occasions ."
            break
            ;;
        "Android")
            echo "Android By Google Developed mobile operating system , It has occupied 70% Market share ."
            break
            ;;
        *)
            echo " Input error , Please re-enter "
    esac
done

Output

 Enter the correct option ：
What is your favourite OS?
1) Linux
2) Windows
3) Mac OS
4) UNIX
5) Android
#? 2
Windows It's a personal computer operating system developed by Microsoft , It's closed source charging .

 Input error options ：
What is your favourite OS?
1) Linux
2) Windows
3) Mac OS
4) UNIX
5) Android
#? 7
 Input error , Please re-enter 
#? 4
UNIX Is the founder of the operating system , Now it has gradually withdrawn from the stage of history , Only for special occasions .

 Enter a null value ：
What is your favourite OS?
1) Linux
2) Windows
3) Mac OS
4) UNIX
5) Android
#?
1) Linux
2) Windows
3) Mac OS
4) UNIX
5) Android
#? 3
Mac OS Apple is based on UNIX Developed a graphical interface operating system , It can only run on the hardware provided by Apple .