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To: "Jamil J. Weatherbee" <jamil@trojanhorse.ml.org>
cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: ioctl() base command groups 
In-reply-to: Your message of "Fri, 24 Oct 1997 15:12:48 MST."
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Date: Sat, 25 Oct 1997 17:35:29 +0930
From: Mike Smith <mike@smith.net.au>
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> 
> Are the groups used in the _IO* macros, which are usually a single
> character supposed to have some systematic system of assignment?

No, not really.  They combine with the other attributes of the ioctl to 
help make the code unique, but there's nothing magic about them.

mike