Function AllocBitMap 

pub unsafe fn AllocBitMap(
    GfxBase: *mut Library,
    sizex: ULONG,
    sizey: ULONG,
    depth: ULONG,
    flags: ULONG,
    friend_bitmap: *const BitMap,
) -> *mut BitMap

libname: “graphics.library” (V39) (Kickstart 3.0)