How to enable more than 256 pty's?

Dag-Erling Smørgrav des at
Tue Oct 2 06:19:57 PDT 2007

Ed Schouten <ed at> writes:
> This is a known issue IIRC. See line 245 of tty_pts.c 1.16. Can be
> easily reproduced by killing the sshd while apps are still running in
> the shell.

It's not that simple.  The question is why t_refcnt > 1 when there are
no processes left attached to the tty.

I managed to reproduce this as follows:

$ script -q 1 script -q 2 script -q 3 script -q 4 tty

if nothing else is going on at the same time, you should always see the
same output, but instead you see a steadily increasing pts number.

Dag-Erling Smørgrav - des at

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