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From: 2212msr@whuts.UUCP (ROBIN)
Newsgroups: net.micro.pc,net.micro
Subject: null as variable in batcg fileh file
Message-ID: <533@whuts.UUCP>
Date: Mon, 10-Feb-86 20:43:18 EST
Article-I.D.: whuts.533
Posted: Mon Feb 10 20:43:18 1986
Date-Received: Wed, 12-Feb-86 07:33:44 EST
Distribution: net
Organization: AT&T Bell Laboratories
Lines: 6
Xref: watmath net.micro.pc:6901 net.micro:13763

Does anyone know how to detect a null as variable input in a batch file?
Specifically:

foo %1   --how do I detect case where %1 is omitted, thus avoiding
	   an error?  I've tried 'if %1=='':goto xx' as well as
==' '