循环 bash 脚本调用的最简单方法

Question

我有一个 bash 脚本。我希望这个脚本每次调用它时都能做不同的事情（模数三）。像这样：

First script call => echo "call 1"
Second script call => echo "call 2"
Third script call => echo "call 3"
Fourth script call => echo "call 1"
Fifth script call => echo "call 2"
Sixth script call => echo "call 3"
Seventh script call => echo "call 1"
...

最简单的方法是什么？

请注意，脚本并不重要。例如：重启后计数器可以回到一：

...
n script call => echo "call 1"
n+1 script call => echo "call 2"
* reboot *
n+2 script call => echo "call 1"
...

就可以了。

感谢您的见解。

Answer 1

最简单的方法可能是将值存储在文件中

if [[ `grep 2 config.txt` ]]
then 
    #run stuff version 2
    echo 3 > config.txt # next run will be 3
elif [[ `grep 3 config.txt` ]]
then
    #run stuff version 3
    echo 1 > config.txt # next run will be 1
else
    #run stuff version 1
    echo 2 > config.txt # next run will be 2
fi

Answer 2

在重击中：

call=$(< call.txt)
case $call in
    0) do_thing_one;;
    1) do_thing_two;;
    2) do_thing_three;;
    *) do_oops_thing;;
esac
echo $(( (call + 1) % 3 )) > call.txt