我們經(jīng)常需要在shell里面做循環(huán)操作,比如每隔幾秒檢查狀態(tài), 或者做什么事; 下面的代碼例子,每隔5秒做一件事,每隔10秒又做一件事情.

$ cat loop.sh
#!/bin/bash

function fun5() {
    echo "in fun5($1)"
}


function fun10() {
    echo "in fun10($1)"
}

typeset count=0
while true; do
    sleep 1
    
    echo "count=${count}"

    if [ `expr ${count} % 5`  -eq 0 ]; then
        fun5 ${count}
    fi

    if [ `expr ${count} % 10`  -eq 0 ]; then
        fun10 ${count}
    fi

    ((count=count + 1))
done

運(yùn)行結(jié)果:

$ ./loop.sh   
count=0
in fun5(0)
in fun10(0)
count=1
count=2
count=3
count=4
count=5
in fun5(5)
count=6
count=7
count=8
count=9
count=10
in fun5(10)
in fun10(10)
count=11
count=12
count=13
count=14
count=15
in fun5(15)
count=16
count=17
...