What does this sh script line do?

[Clarence Dold]

in article <1991Jun06.172119.19494 at ka3ovk>, albers at ka3ovk (Jon Albers) writes:

> . ${NEWSCONFIG-/usr/lib/news/bin/config}

> It blows up on this line with the error 'Bad substitution', however,
> under SCO UNIX, it work just fine.  What is it supposed to be doing?

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

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Clarence A Dold - dold at tsmiti.Convergent.COM
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