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From: =?ISO-8859-2?Q?Ren=E9_Berber?= <rberber AT prodigy DOT net DOT mx>
Subject:  Re: Problem with shell script
Date:  Sun, 24 Jul 2005 15:05:20 -0500
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Message-ID: <dc0s8t$sj4$1@sea.gmane.org>
References:  <20050724191302 DOT 58251D10DB AT rekin6 DOT o2 DOT pl>
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Marek wrote:

> When I put commands below in command line:
> i=1
> echo $i
> i=$(($i+1))
> echo $i
> 
> everything works well (i is incremented from 1 to 2), but when I run this as a shell script the result is:
> 1+1 instead of 2
> 
> How should I do incrementation in shell script?

It depends on what shell and version you are using.

In bash (version > 2.05) I use:

  let i=i+1

And you can also do it inside a loop, like:

  for (( i= 1; i <= $3; i++ )); do
    ...

those double parenthesis are not available in old bash versions.

HTH
-- 
René Berber


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