How to pass paramter to exported dll function?

[Dylanuk]

{
MsgFunction gethostname(0);
hinstDLL = LoadLibrary("wsock32.dll");
if (hinstDLL != 0){
gethostname = (MsgFunction)GetProcAddress(hinstDLL, "gethostname");

}
from hear i dont know how to use the "gethostname" function,
what do i need to learn?