serial port in C

Programmer Question

I have written a program in C to send a byte to serial port (com).
I have used BIOSCOM to send data
but I guess that it doesn't open the port.
Please tell how I can open and close a com port in C.

My code is here:

#define COM1 1;
bioscom (1 , 65 , COM1);

Please help me...

Find the answer here