CXR problem with a modem

[chris at umcp-cs.UUCP]

There are lots of possible solutions, but we happen to like one
in particular:  add another major device number that allows opens
without waiting for a carrier, and simultaneously suspends normal
opens.  In fact we use just such a modified driver for our UUCP
dialout.  Our 3 Vadic 3451s can be (are) used for dial in and
dial out ``simultaneously'' without modifying anything but the
kernel.

If there is enough interest I'll post the changes to the 4.2BSD
dz.c.  (Similar changes in dh.c accomplish the same thing for DH
lines, and I'm sure the same can be done for DMFs; we just happen
to have the Vadics on DZs.)
-- 
In-Real-Life: Chris Torek, Univ of MD Comp Sci (301) 454-7690
UUCP:	{seismo,allegra,brl-bmd}!umcp-cs!chris
CSNet:	chris at umcp-cs		ARPA:	chris at maryland