DTR Flow Control

[Michael Cardenas]

Is DTR flow control supported?

There's a comment in comm.c in SetCommState that says it's not, but 
EscapeCommFunction has a SETDTR case and a CLRDTR case.

Below are the lines I'm talking about.

I'm working on an app that asks for DTR flow control and uses overlapped 
IO when using a modem. It establishes a modem connection, but then it 
can't send any data over the connection. I'm using an external modem on 
a serial port.

------------------------------------------------------------------------

if (lpdcb->fDtrControl == DTR_CONTROL_HANDSHAKE)
      {
             WARN("DSR/DTR flow control not supported\n");
      }

comm.c line 1069

-------------------------------------------------------------

case SETDTR:
    	        TRACE("SETDTR\n");
#ifdef TIOCM_DTR
    		direct=TRUE;
    		result= COMM_WhackModem(fd, 0, TIOCM_DTR);
    		break;
#endif

comm.c line 548