RC>    I am writing a Maximus door program, everything is
 RC> working fine except that I don't know how to check for
 RC> carrier detect.  Could you please tell me how to do this
 RC> using the file handle passed to my program from Maximus. 
 RC> Also I would like to know how to change the state of the DTR
 RC> line and read the state of the DSR line.

Look up the DosDevIOCtl API function, category 1 (async ioctls), functions
67h (query modem input signals), 53h and 73h (set / query DCB paramaters),
and 46h (set modem control signals).

Cheers,
             Jim
             jim{at}aisbbs.com 
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