I have never done it in C, but this guy has done it in QBasic on the receive end: http://ptouchman.blogspot.hk/2014/07/serial-flow-control-rts-in-qbasic.html
You need a loop of some sort that stops transmitting when the DTR line is set to false and resumes when its set to true. I think you can send the contents of the file "raw" to the serial port using a terminal program too. Whats interesting is Apple's programming examples in the IW II technical reference don't bother with flow control at all. They just open up the serial port and write characters to it.
You need a loop of some sort that stops transmitting when the DTR line is set to false and resumes when its set to true. I think you can send the contents of the file "raw" to the serial port using a terminal program too. Whats interesting is Apple's programming examples in the IW II technical reference don't bother with flow control at all. They just open up the serial port and write characters to it.