[SOLVED] Passing variables to a program in a bash script

danbopes · 12-30-2010, 06:44 AM

Trying to do a simple bash script, and having some issues. I am relatively new to bash, and did my best to search, but idk what exactly to search for.

Doesn't work:

Code:

DIALOG="1 test"
dialog --menu "Choose OS for install:" 10 30 1 ${DIALOG}

Works:

Code:

dialog --menu "Choose OS for install:" 10 30 1 1 test

Just trying to figure out how to tell it it's two different arguments and not one. I'm sure this is an issue with escaping, but I'm not sure how to fix it.

grail · 12-30-2010, 06:56 AM

Well some more information would be nice, like when you are executing the lines above, are they all being done at the prompt or from a script?
This worked fine for me (at prompt):

Code:

$ x="10 30 1 1 test"
$ dialog --menu "Choose OS for install:" $x

catkin · 12-30-2010, 07:06 AM

The quoted code using ${DIALOG} should have been functionally equivalent to the other quoted code. Can you give some detail on "doesn't work"?

danbopes · 12-30-2010, 07:08 AM

Code:

DIALOG="10 30 1 1 test"
dialog --menu "Choose OS for install:" $DIALOG

Gives me:
Error: Expected at least 6 tokens for --menu, have 2.

I am trying to run this through a script (as noted in the title, and in my post).

catkin · 12-30-2010, 07:20 AM

This is very mysterious; $DIALOG seems to be working as "$DIALOG". Please try this at the command prompt and in a script and post the output

Code:

DIALOG="1 test"
for word in $DIALOG 
do
    echo $word
done

You will get a > prompt after the for command when entering it at the command prompt and until you enter the final done.

danbopes · 12-30-2010, 07:40 AM

ok, I figured out what the problem was (1 of them anyway). I was using IFS to read a variable (newlines and stuff), and I never unset it after, so that solved one problem.

Here is my second problem (instead of making a new thread, cause it goes along with the title anyway).

Code:

#!/bin/bash

DIALOG="1 \"test with spaces rawr\""
dialog --menu "Choose OS for install:" 10 70 1 $DIALOG

It's not seeing the quotes when I do that, so it's reading it as 5 arguments and not 2. (1, "test, with, spaces, rawr") not (1, "test with spaces rawr")

catkin · 12-30-2010, 07:50 AM

That is as-designed behaviour. Shell Operations details the mechanism that leads to such behaviour.

You can do what is intended by that code by using an array:

Code:

DIALOG=(1 "test with spaces rawr" )
dialog --menu "Choose OS for install:" 10 70 1 "${DIALOG[@]}"