Can someone please help me with serial communication

Hi,
I know the basics of RS232 and my hardware is configured,all I need help is with writing a program in C to transmit and recieve data.I am comfortable with both windows and Linux enviorment

What have you tried so far, and what are you having trouble with?

Seriously, there is a wealth of information about this on the net. Your question is so vague, the best we could do is search for resources and offer them to you - but why not just do this yourself and cut out the middle man?

Also note there are some free pre-existing libraries you could use - there's a forum post from last year that links to such a library (I'll leave it as an exercise to the OP to find this thread for themselves).