lua_pushcclosure

lua_pushcclosure[-n, +1, m]

void lua_pushcclosure (lua_State *L, lua_CFunction fn, int n);

Pushes a new C closure onto the stack.

When a C function is created, it is possible to associate some values with it, thus creating a C closure (see §4.4); these values are then accessible to the function whenever it is called. To associate values with a C function, first these values must be pushed onto the stack (when there are multiple values, the first value is pushed first). Then lua_pushcclosure is called to create and push the C function onto the stack, with the argument n telling how many values will be associated with the function. lua_pushcclosure also pops these values from the stack.

The maximum value for n is 255.

When n is zero, this function creates a light C function, which is just a pointer to the C function. In that case, it never raises a memory error.