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Date: Wed, 31 Aug 2005 13:49:14 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Gary Kline <kline@tao.thought.org>
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Cc: FreeBSD Mailing List <freebsd-questions@freebsd.org>
Subject: Re: Doing a modulo in /bin/sh??
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In the last episode (Aug 31), Dan Nelson said:
> In the last episode (Aug 31), Gary Kline said:
> > I can grab the results of "w=$date+%U)"; in C an use the modulo
> > operator; is there a way to do this is /bin/sh?  ot zsh?
> > 
> > #/bin/sh
> > w=$(date +%U)
> > echo "w is $w";
> > (even=$(w % 2 ));       ## flubs.
> > echo "even is $even";       ## flubs.
> > 
> > if [ $even -eq 0 ]       ## flubs, obv'ly.
> > then
> >         echo "week is even";
> > else
> >         echo "week is odd";
> > fi
> 
> zsh has the % modulo operator, so xmod=$(( x % n )) .

Silly me, I forgot to read the source to /bin/sh's arithmetic code.  It
knows about % too, so $(( x % n )) will work anywhere.

-- 
	Dan Nelson
	dnelson@allantgroup.com