Can I see _totalframes on a loaded swf?

Hey guys!

I have a program where I am supposed to first load a swf in the first frame (i will not know how long that swf is), and when that has finished playing the main program i supposed to move on to the next frame. Now my question is, can I somehow figure out how long that swf is from within my main program or will I have to put a simple _root.gotoAndPlay(2); in the last frame of my loaded swf?

Thanks for looking!