Questions about LoadRWops & SaveRWops RWops

Hi,

I’m looking at http://www.kekkai.org/roger/sdl/rwops/rwops.html and i
have some questions, i’m planning on having a file containing various
items, amongst others, several bmp’s, will Load_BMP_RW be able to read
the BMP files & know where they end?

Also, in the examples on that page they use SDL_RWFromFP, wich seems to
take 2 pointers, a file pointer & an integer, i suppose the integer
indicates the starting position for the read operation performed by
SDL_LoadBMP_RW ?

Cheers