[physfs] Possible API oversight? request for PHYSFS_duplicate for PHYSFS_File

[ell1e]

Sadly, there seems to be one API oversight giving me quite a headache
right now: I have a need for PHYSFS_duplicate for PHYSFS_File.

Rationale: I'm wrapping PHYSFS_File the same way a PHYSFS_Io is wrapped
by PhysFS with a custom I/O layer, which needs to implement a
duplication mechanism. Currently this appears to be really difficult,
because apparently there is no way to duplicate the underlying
PHYSFS_File I wrap. Since we're not meant to access internals (docs say
opaque is all we get!) it is even more important that this functionality
is provided by physfs itself.

Could this possibly be added? I'm usually compiling from hg master
anyway, so such an improvement should reach me really quickly if it were
ever to be added even if there isn't a release soon after, possibly
avoiding me lots of headache once it does. I understand if it's not
possible any time soon, but it would really help a lot.

Regards,

ell1e