Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!CSVAX.CALTECH.EDU!andy
From: andy@CSVAX.CALTECH.EDU (Andy Fyfe)
Newsgroups: gnu.bash.bug
Subject: parameter substitution (bash 0.99)
Message-ID: <8906132054.AA07686@csvax.caltech.edu>
Date: 13 Jun 89 20:54:43 GMT
Sender: daemon@tut.cis.ohio-state.edu
Distribution: gnu
Organization: GNUs Not Usenet
Lines: 6

Given
	X=
	echo ${X:-abcd}
bash will echo "", while /bin/sh (sun, 3b1) and /bin/ksh (3b1) will
echo "abcd".  The man pages talk about varibles being "set and non-null"
or "not set or null".