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From: Carl Johnson <carlj@peak.org>
Date: Thu, 24 Jun 2010 21:42:37 -0700
In-Reply-To: <20100624183407.GA49923@holstein.holy.cow> (parv@pair.com's
	message of "Thu\, 24 Jun 2010 08\:34\:07 -1000")
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Subject: Re: check for numeric content in a shell script (FreeBSD sh)
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parv@pair.com writes:

>>     if expr "$arg" : "[1-9]*\.\{0,1\}[0-9]*$" > /dev/null
>
> That regex considers "." a number but not "0.9" (this one seems to
> be due to typo) nor a negative number.

I had been pointing out an error in the regular expression that
someone else had posted, but I obviously didn't do any better.

> I would personally to use egrep or awk (printf "%s" "${arg}" | egrep
> "${regex}" [0]) instead of expr.

I would probably just perl for the whole thing, especially seeing the
limitations in trying to use expr.  Thanks for pointing out another
approach.

-- 
Carl Johnson		carlj@peak.org