Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!lll-winken!uunet!steinmetz!davidsen
From: davidsen@steinmetz.ge.com (Wm. E. Davidsen Jr)
Newsgroups: comp.unix.questions
Subject: Re: Bourne Shell: Variable defined?
Keywords: Bourne shell, elementary question
Message-ID: <13473@steinmetz.ge.com>
Date: 28 Mar 89 22:11:29 GMT
References: <1819@umbc3.UMBC.EDU> <25130@hqda-ai.UUCP>
Reply-To: davidsen@crdos1.UUCP (bill davidsen)
Organization: General Electric CRD, Schenectady, NY
Lines: 9

I've been following this, and I'm not sure the right answer has come
out. The construct is ${foo+X} okay, but I think you want
	[ -z "${foo+X}" ] && echo "foo set" || echo "foo not set"
construction, because without the -z some funny things seem to happen on
older (V7/Sys III) shells. Just a thought.
-- 
	bill davidsen		(wedu@crd.GE.COM)
  {uunet | philabs}!steinmetz!crdos1!davidsen
"Stupidity, like virtue, is its own reward" -me