RE: Kick a dog....

Joe Barrera (
Fri, 1 May 1998 14:18:29 -0700

> From: Joachim Feise []
> "Ask Bill why function code 9 [in QDOS and still in MS-DOS, more than ten
> years later] ends in a dollar sign. No one in the world knows that but
> - Gary Kildall, author of CP/M

Well, in one way, this is an easy question to answer: function code 9 in
QDOS (output string) uses a terminating dollar sign because CP/M BDOS
function code 9 does [1], and QDOS was just a CP/M clone. So I guess Gary
really meant that no one knows why BDOS function code 9 requires a
terminating dollar sign.

I had always just assumed it was another DEC-ism in CP/M, of which there are
many. Drives and devices with names of the form "foo:", PIP (peripheral
interchange program), the use of forward slashes for program options, etc.
At any rate, I'd guess it's probably the same reason why $ means end-of-line
in Unix regular expressions.

- Joe

Joseph S. Barrera III <>
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