Comment 3 for bug 21705

> So, one way to implement this without requiring anything of
> gdmflexiserver
> or similar apps would be to check on startup which VT is ours, and
> then
> while running a hack, check occasionally to see if the active VT is
> our VT. If it isn't, or when the user hits the "new login" button,
> then throttle, use VT_WAITACTIVE to block until the user returns,
> then unthrottle.
>
> Does this seem like a reasonable approach?

That seems reasonable, though I'm not entirely comfortable with the
assumption that the VT that is current when xscreensaver starts up is
the VT that the X session is running on; if that's not the case for
whatever reason (e.g., something earlier in the startup script was
being slow, and the user switched VTs to figure out why) the failure
mode is not so good.

Another thing that might be a problem (I haven't checked) is whether
these ioctls work from unprivileged processes. E.g., xscreensaver
cannot use the VT_LOCKSWITCH ioctl (which would be a nice option to
prevent VT switching when the screen was locked) because that ioctl
can only be called by root (and xscreensaver has long discarded its
privs by the time it would want to use it).

--
Jamie Zawinski <email address hidden> http://www.jwz.org/
                     <email address hidden> http://www.dnalounge.com/
                                          http://jwz.livejournal.com/