> The current fsys interface allows the people to write fsys > implementations by using the fsys definition interface. It is (with > some minor modifications) the same strategy used by Adobe in their > Acrobat SDK.
Ah ok, I wasn't entirely sure it was documented as such. (I had a suspicion it was meant to be done that way). It is documented in the reference manual. Basically you provide a pdf_fsys_impl_s structure containing the pointers to the functions implementing a specific filesystem to 'pdf_fsys_create'. In the calls to the filesystem API (such as pdf_fsys_get_free_space) you pass the pdf_fsys_t value created by pdf_fsys_create or NULL, meaning that we want to use the default filesystem implementation (namely the disk filesystem implementation).
