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Simple BASH script; understanding loops and case

I'm trying to acquaint myself with shell scripting by following this guide and am getting stuck testing out this script.

All I want it to do is have the script loop continuously, and when I type in a command and 2 optional arguments, it performs the task. Simple way of testing whether I've "got it" or not.

Specific questions:
Am I using the cut command properly?
Is [ ] usable when trying to cut by blank spaces?
Am I using case right?
Is there a way I could have the loop exit if I press ctrl-c or something like that?

Code:

while [ read line ]

do

        command="$(echo $inputline | cut -d[ ] -f1)"

        arg1="$(echo $inputline | cut -d[ ] -f2)"

        arg2="$(echo $inputline | cut -d[ ] -f3)"

        

        case $command in

                copy) & cp &arg1 &arg2

        esac

done

Well your script reads some input into a variable called line but the rest of the script doesn't do anything with the variable $line, it then starts to work with the variable $inputline. line is actually the name of a command so it's a poor choice of variable name.

With cut, I think the correct way of using a space as the field separator is with double quotes

Code:

echo $inputline | cut -d " " -f 2

I can't make out what you're trying to do with the case command, perhaps something like this?

Code:

case $command in

  copy)

    cp $arg1 $arg2

    ;;

esac