Screen locker

[Nicolas George <george@nsup.org>]

Hi.

I need a screen lock mechanism that does not let another user open a new
session (= if you lock to go to the bathroom, you get your place back),
but after a configurable amount of time (= if you lock and go to the
movies, you might not get your place back) has a dialog “this computer
is locked since…” and a button “force logout” (= your processes will not
waste resources until the next reboot).

Is there something like that available in Debian? Or not in Debian?

(We are using lightdm, but since we do not want to let extra sessions,
the solution does not need to cooperate with the display manager, so
that information should not be relevant. It is not an issue if users can
ctrl-alt-F2 to another VT and startx.)

Oh, I forgot: it needs to work with passwd and shadow from NIS, because
it's still the 20th century around here.

Regards,

-- 
  Nicolas George