30 Jan
2023
30 Jan
'23
2:09 p.m.
In Plan 9 we made /dev/tty (there called /dev/cons) fully virtual, a
fiction that provided the semantics. I agree that it's a pity the /dev/tty
kludge persists as a kernel hack.
And then we have pttys, speaking of pitys.
-rob
On Mon, Jan 30, 2023 at 6:50 PM <arnold(a)skeeve.com> wrote:
> Where
this is done is, as I posted earlier, in /etc/init. Init
opens the
> tty device and dups it to 1 and then invokes
either the shell (if
we're in
> single user mode) or getty for interactive
mode.
> This was done in V6 and PWB (1). In V7, init added a second dup for
file
> descriptor 2.
What I really like is how in V8 - V10 /dev/tty was a (sym)link to
/dev/fd/3,
and init simply did one more dup call. That eliminated the special tty
device
driver and was a lovely generalization / simplification. It's too bad this
was never picked in the commercial Unixes or in Linux.
Arnold