Addition in bash

[Andrew Farris]

On Wed, 2009-10-14 at 00:24 -0700, Ray Parrish wrote:
> Hello,
> 
> I have the following script fragment
> 
> Seconds=0;
> while [ "$Seconds" -lt "60" ]
>   do
>   sleep 5;
>   Seconds=$Seconds+5;
>   padsp espeak "$Seconds"
> done
> 
> For some reason Seconds becomes "0+5" instead of the integer value 5 
> which is what I am attempting to get it to be.
> 
> Does anyone know how to do integer math in bash?

I believe it should look like this: 

---------------------------------------
#!/bin/bash
Seconds=0;
while [ "$Seconds" -lt "60" ]
  do
  sleep 5;
  Seconds=$((Seconds+5));
  padsp espeak "$Seconds"
done
---------------------------------------

This works for me, though it gives no output unless I replace 'padsp
espeak' with 'echo'.

Hope that helps!


-- 
Andrew
_____________________________
Registered Linux User: 473690
Registered Ubuntu User: 22747