Programming :: C Syntax - Passing In Unknown Number Of Arguments?

I need to write a wrapper function around the mvprintw function, like so:

int smvprintw( ? )
{
// Do various checks/modifications on the first two arguments (int y,
int x) first,
// and then
return mvprintw ( ? );
}

How should I write the args for smvprintw so that I can pass all the data correctly to mvprintw, and also do my checks on the first two args (for example, to modify them)? I'm confused by the prototype of mvprintw: This is mvprintw as listed in the man pages:

int mvprintw(int y, int x, const char *fmt, ...);

And this is how I saw it in ncurses.h:

extern NCURSES_EXPORT(int) mvprintw (int,int, const char *,...)

I believe the "..." refers to the unknown number of items after const char * fmt. Will it suffice to do something like "int smvprintw(int y, int x, const char * fmt, void * etc)" and then "mvprintw(y, x, fmt, etc)" inside the function?