Shell Script--loop structure

The Shell's loop structure has while and for two types

While loop

While following the judgment condition, the judging condition can be more than one, but each judgment condition should be enclosed in a separate [], and then multiple judgments are used &&, | | to represent the meaning.

Example:

#!/bin/bash# file name: test.shtot=0num=10while [$num-gt 0]do    tot=$ (($tot + $num))    num=$ (($num-1)) Done    echo " The sum is "$tot

The results of the operation are as follows:

　　

Shell Script--loop structure