Accept pre-mounted FUSE descriptor

[fdegros]

This allows rar2fs to accept a mount point in the form of /dev/fd/xxxx where xxxx is an integer, and pass it to the underlying libfuse.

This is useful if the underlying libfuse itself can deal with pre-mounted FUSE descriptors, as does the patched libfuse used in ChromiumOS.

[hasse69]

In general looks good, just some minor things to address.

[hasse69]

Next time I think you should amend your commits so that we do not end up with multiple commit messages since that makes it harder to squash them nicely. Or possibly, I have misunderstood something :)

[fdegros]

I can't see any way for me to merge this pull request.

There is a green box with:

Changes approved
This branch has no conflicts with the base branch
Only those with write access to this repository can merge pull requests.

But no Merge Pull Request green button as described in GitHub - Contributing to a Project.

Can you see this button and merge the pull request?

[fdegros]

Thanks

[hasse69]

No problem. But as you can see the two squashed commits does not turn out so nice in the commit message. But squashing them was the most natural thing to do here. If you would have amended your second commit towards the first I believe it would have looked better. But really, no big deal.