如何在自定义 pipe 命令脚本中使用 bash tail 命令？

Question

I want to use tail in my custom pipe command.

For example, I want to execute this command:

>ls -1 | tail -n 1 | awk '{print "last file is "$1}'
>last file is test.txt

And I want to make it short by making my own custom script. It looks like this:

>ls -1 | myscript
>last file is test.txt

I know myscript can get input from "ls -1" by this code:

while read line; do
    echo last file is $line
done

But I don't know how to use "tail -n 1" in the custom pipe command code above.

Is there a way to use a pipe command in another pipe command script?

Or do I have to implement the code which does the same process as "tail -n 1" myself?

I hope bash has some solution for this.

Answer 1

Try putting just this in myscript

tail -n 1 | awk '{print "last file is "$1}'

This works as the first command (tail) consumes the stdin of your script. In general, scripts work as though you typed their contest as-is to the terminal.