Shell script help

Björn König bkoenig at cs.tu-berlin.de
Wed Jun 29 08:35:38 GMT 2005


Mike Jeays wrote:

> "man expr" to give the short answer to your first question:
> 
> As an example, x=`expr $x + 1`
> 
> 536 ~ $ x=4
> 537 ~ $ x=`expr $x + 1`
> 538 ~ $ echo $
> 
> Note the back-quotes to execute a command and return the result, and the
> need for spaces between each token in the expr command.

sh(1) is able to evaluate arithmetic expressions too, e.g.

   x=$(($x+1))



Björn


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