need modem control lines info

[Jan Isley]

I need some information on controling and determining the status of
modem control lines with SCO SYSV/386.  More precisely, I need to:

1. Set DTR on.
2. Set DTR off.
3. Set RTS on.
4. Set RTS off.
5. Determine the state of CD.
6. Determine the state of CTS.
 
I am NOT using this with a modem.  I need to communicate with a very
non-standard device (an external industrial > tape drive), which has
its own very strange communication protocol.  Therefore, RTSFLOW and
CTSFLOW are not adequate, as they set the port behavior according to
some other protocol.  To initiate communications with this device, I
am required to set RTS off, wait for CD to go on, set RTS on, wait
for CD to go off, and so on.  Therefore, I need to set the pins, or 
determine the state off the pins directly.

So far, I cannot find this information in the /usr/includes.  My SCO
tech support distributor says it cannot be done.  I am not inclined to
believe this response.

Thanks.
-- 
Issha Zetsumei                        | home jan at bagend 404-434-1335
One arrow, then you die.              | known_universe!gatech!bagend!jan 
                                      | work jli at mdt    404-642-3005