This implementation is on top of inodes instead of fds as linux does it.
If I start finding ports/software that relies on epoll allowing
duplicate inodes, I will do what linux does.
I'm probably missing multiple epoll_notify's which may cause hangs but
the system seems to work fine :dd:
If pseudo terminal buffer was filled, old implementation would overwrite
old data. This is bad if producer is capable of producing more data than
consumer can handle.
This patch implements posix_openpt() and ptsname()
grantpt() and unlockpt() are left in LibC as stubs, as posix_openpt
currently does all of the needed work.