[physfs] Using ZIP and GRP files

[Ryan C. Gordon]

> I am new is PhysFS and have been tying to intergrate it into my code
> over the last few days. I have got the hang of how the read and write
> paths work but can't figure out how you write a ZIP or GRP file using
> PhysFS - presumably you can? Or do I need something else?

You can't generate or modify archives right now, the only write support is
to real files on a physical filesystem.

The structure is in place in physfs to let you write out a zipfile or
whatnot, but it isn't implemented (since there are performance and
resource considerations to weigh, and games generally don't need to do
this).

--ryan.