I noticed that when someone tries to open a pty,
that has no master side, this task loops in running state.
Apparently, it is not correct.
Really, I suspect that nobody knows what should be done in
this situation. F.e. Solaris sleeps. (Taking into account
that Solaris<=2.3 utmp/utmpx is pretty broken, you will
have couple of dozens sleeping messaged/talkd etc. after
one day of work)
I'd just return EIO (or something a sort of it).
Alexey Kuznetsov.