Question about Sockit board communicating with PC

I am new in FPGA design. I want to accelerate my C language code running in PC. Therefore I transform partial C language code into FPGA code on SOCKIT board(http://www.altera.com/b/arrow-sockit.html). However,I have no idea how the C language code running in PC communicating with the FPGA code on SOCKIT board. Can anyone help me?Or give me an example? Thanks.