External predicates : file handling

I am building an application in eclipse in which i use external predicates
(written in C).
These predicates access some files (always the same files).
To do this every time i call an external predicate, i use
fopen() and fclose() to access the files.
Is there any way to keep the files open as long as eclipse is running?
(either by opening a stream in eclipse and passing as an argument to
external predicate, or by putting the file pointers in global variables),

Eddie