On Sun 10 Jan 2021 at 09:44:18 -0500, Mouse wrote: > >> This makes me wonder if perhaps login sessions should have their > >> stdin/stdout/stderr set up on /dev/tty instead of the actual ctty > >> device. But if that's done, will the `real' ctty device even be > >> open? [...] > > It actually occurs to me that this is a potential problem even today: > what happens if all the processes in a session close the descriptors > they have on the ctty, and there are no others lying around in other or similarly, if they TIOCNOTTY it (although tty(4) tells me it's obsolete) > processes, and then one of those processes tries to access /dev/tty? > It would be an unusual session, true, but there's nothing preventing it > from happening as far as I can see. Would the underlying tty driver > explode upon getting I/O calls when it isn't open, or what? I think sys/kern/tty_tty.c is the implementation of /dev/tty, and it seems you get ENXIO. Also each read/write call goes to the *current* controlling tty, freshly looked up. > /~\ The ASCII Mouse -Olaf. -- Olaf 'Rhialto' Seibert -- rhialto at falu dot nl ___ Anyone who is capable of getting themselves made President should on \X/ no account be allowed to do the job. --Douglas Adams, "THGTTG"
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