Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!spool.mu.edu!uunet!ogicse!qiclab!onion!jeff
From: jeff@onion.rain.com (Jeff Beadles)
Newsgroups: comp.unix.questions
Subject: Re: What does this sh script line do?
Message-ID: <1991Jun13.041427.25609@onion.rain.com>
Date: 13 Jun 91 04:14:27 GMT
Article-I.D.: onion.1991Jun13.041427.25609
References: <1991Jun11.045504.26169@thunder.mcrcim.mcgill.edu> <2142@mitisft.Convergent.COM>
Lines: 20

dold@mitisft.Convergent.COM (Clarence Dold) writes:

>Isn't the correct syntax ":-" ?  My shell likes it with or without the : 
>. ${NEWSCONFIG:-/usr/lib/news/bin/config}
>              ^

Depends on what you want.  The variable is expanded as:

If the NEWSCONFIG variable is set and non-null, use it, else use "/usr/..."

Without the colon, take the above line and delete "and non-null,"

Note, that the ':' operator is not very portable.  I've ran into a couple of
systems that don't support it.

By the way, the ':' is discussed in "tfm" under "Parameter Substution..." :-)

	-Jeff
-- 
Jeff Beadles		jeff@onion.rain.com