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Getting User Input in a Shell Script

Jun 29, 2009  By Mitch Frazier
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RE: echo $?

Chanan's picture
Submitted by Chanan (not verified) on Wed, 07/01/2009 - 05:42.

The $? variable is the exit status of the last command. $1 is the first command line argument passed to the script.

For example, make a script like the following (give it some name I used test.sh):

#!/bin/bash
echo $1
exit 23

Make it executable: chmod 755 test.sh
Then run it with an argument, for example: ./test.sh "Hello"
Then after that run: echo $?
You'll see that "echo $1" in the script returned the argument you passed, while "echo $?" returned the number after "exit" in the script (the exit status).

I used an exit status other then 0 (true) or 1 (false) to hopefully make the example clearer.

Oops, meant to put it as a

Chanan's picture
Submitted by Chanan (not verified) on Wed, 07/01/2009 - 05:45.

Oops, meant to put it as a reply to Arup's question.

echo $?

Arup's picture
Submitted by Arup (not verified) on Tue, 06/30/2009 - 18:23.

Good tip Thanks,

but how does the ? in echo$? work
IS it like $1 ?

Zenity

Anonymous's picture
Submitted by Anonymous (not verified) on Mon, 06/29/2009 - 23:04.

I also use Zenity for most of my shell scripts, being on gnome I guess thats my alternative to kdialog.

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