C call function without knowing parameters

Question

I need to write a function that is given a function pointer, and a list of types (integers that represent a type). I can obtain the values to pass to the function pointer, but am wondering how to call it. This needs to happen at run time and i dont know how many arguments i will have. e.g.
void call_function(void (*func)(),int types[],void *args[]){
int i;
for(i=0;types[i]!=0;i++){
// Add this argument
// call the function with the arguments

Answer 1

I just found passing a function pointer was the best way to do something interesting with my WM.
I had a function that selected and called a window tiling function.
But when I started adding multimonitor support, I needed a function that did a few housekeeping bits, then tiled each monitor.  It was ugly and repetative until I had the first function pass a pointer to the tiling funtion to the monitor function.  The monitor function loops through monitors and calls whichever function it was passed.
But back OT.  I may have misread the first time.  Are you writing just the calling function, or are you also writing the function that is being passed as a function pointer?  If you are only doing the former, you cannot do this.  You must call a function with the correct number of arguments - unless it was declared as a variadic function.  If you are writing that function to - then see va_args, and you can do this.
In either case - this may be a good place for some inline assembly.  May being the operative word there - I do a good bit of C, and have dabbled in assembly, but I've never really combined the two.  But as I understand it, you should be able to push your arguments to the stack, then call the function.  This is how arguments are passed afterall.