tree 4541df8890654a784bdb40b9f5fe94dc028ea2e8
parent baf95a5aefe885ef8a675759c63d43649d312ec6
author Rich Felker <dalias@aerifal.cx> 1535496015 -0400
committer Rich Felker <dalias@aerifal.cx> 1535496072 -0400

set errno when fileno is called on a FILE with no underlying fd

this is a POSIX requirement.

also remove the gratuitous locking shenanigans and simply access f->fd
under control of the lock. there is no advantage to not doing so, and
it made the correctness non-obvious at best.