SHELL 编程入门与提高(三)SHELL中的语句详解(下)
pdksh/bash下for语句的第一种形式是:
#!/bin/tcshset day = 5switch ( $day )case 1: echo “Today is Monday”; breakswcase 2: echo “Today is Thuesday”; breakswcase 3: echo “Today is Wednesday”; breakswcase 4: echo “Today is Thursday”; breakswcase 5: echo “Today is Friday”; breakswcase 6: echo “Today is Saturday”; breakswcase 7: echo “Today is Sunday”; breakswdefault: echo “Oops! Day is Error!” ; breakswendswbreak和exit语句
我们需要掌握break和exit的用法。break通常被用来终止一个循环,比如for,until,repeat命令。exit语句通常用来终止一个shell程序。你可以通过exit返回一个数值,当其他程序调用这个shell程序时,可以通过返回的这个数值($?或者$status变量)来作出相应的决策。