Optional
arg1: *First argument that is passed from caller.
Optional
arg2: *Second argument that is passed from caller.
Optional
arg3: *Third argument that is passed from caller.
Optional
arg4: *Fourth argument that is passed from caller.
Optional
arg5: *Fifth argument that is passed from caller.
Optional
arg6: *Sixth argument that is passed from caller.
Optional
arg7: *Seventh argument that is passed from caller.
Optional
arg8: *Eighth argument that is passed from caller.
Callback used by Events and EventHandle functions. Note the callback is limited to 8 arguments.