Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!ucbvax!ulysses!gsf
From: gsf@ulysses.homer.nj.att.com (Glenn Fowler[drew])
Newsgroups: comp.unix.questions
Subject: Re: Re^2: Bourne Shell: Variable defined?
Summary: ${parameter+word}
Message-ID: <11361@ulysses.homer.nj.att.com>
Date: 23 Mar 89 05:41:54 GMT
References: <1819@umbc3.UMBC.EDU> <9899@smoke.BRL.MIL> <2202@solo1.cs.vu.nl> <1605@fig.bbn.com>
Organization: AT&T Bell Laboratories, Murray Hill
Lines: 8

# determine if var is set in Bourne-based shells
case ${var+1} in
1)	echo var set ;;
*)	echo var not set ;;
esac
-- 
Glenn Fowler    (201)-582-2195    AT&T Bell Laboratories, Murray Hill, NJ
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