Having resource variables over several scripts

Hey, I am trying to have e.g. a file opened over several scripts. When opening a file with "fopen" I receive a variable of the type resource (like "Resource ID #3"), but when I try to save this variable in the SESSION and try to use it on another page, I get a "null" variable. Because I need to have the same and exact resource (not opened every time I load a new page) and since it is apparently not possible to store it in a session, I wanted to ask if somebody had the same issue once, and maybe there is some help out there. Could I somehow serialize the resource, then give it to another page via GET or POST? I would really appreciate if somebody has some hints... Thanks, benni. -SDG-