转载自:http://blog.sina.com.cn/s/blog_6151984a0100el04.html
select 表达式是一种bash的扩展应用,动作包括:
自动用1,2,3,4列出菜单 (没有echo指令,自动显示菜单)
自动read输入选择 (没有 read指令,自动输入)
赋值给变量 (没有赋值指令,自动输入数字后,赋值字符串给变量)
select典型例子
[macg@machome ~]$ vi test.sh echo "What is your favourite OS?"
select var in "Linux" "Gnu Hurd" "Free BSD" "Other";
do
break select本身就是一个循环,break是当选择后,就跳出循环
done
echo "You have selected $var"
[macg@machome ~]$ sh test.sh What is your favourite OS?
1) Linux
2) Gnu Hurd
3) Free BSD
4) Other
#? 2
You have selected Gnu HurdSelect输入选择是数字,但变量值却是字符串
虽然select本身就是循环,但不建议用他的循环 ,因为select虽然循环却不再显示菜单,只循环输入,所以seleckt 语句干脆直接用break,只执行一次,在其上另配while循环
while echo "display current netconfig:" do
select vi in "ifconfig -a" "hosts" "netmasks" "quit"
do
case $vi in 虽然输入是1,2,3,4,5,但case变量输入值却是菜单项(字符串)
"ifconfig -a") /sbin/ifconfig -a;;
"hosts") more hosts;;
"netmasks") more netmasks;;
"quit") return 0;;
*) continue;;
esac
break
done
done
$ sh test display current netconfig
1) ifconfig -a 3) netmasks
2) hosts 4) quit