Regarding Function module exits

Hi,

function module exit :EXIT_SAPLAFAR_002

include in function module exit :ZXAFAU02

include exit is implemented :LAFARF70

Main Program :SAPLAFAR

Please help me how to execute this funcion moduel exit, and how to work on it, I could not find out any transaction for it, and provide me some links to understand the use of function module exits.

Thanks & Regards,

vinesh.