30 Jan
2023
30 Jan
'23
1:50 p.m.
> 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