> 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).