18.04: AccountServices settings for auto logout

[Robert Heller]

Is there a way with Ubuntu 18.04 *using only CLI tools* (eg editing a system 
file somewhere) to set a user to be auto logged out when idle for a period of 
time (say 15-20 minutes)?

I have a batch of diskless workstations, using LDAP for authentification.  
Generally for "guest accounts", but there are a few "real" users that log in 
from time to time.  One in partitular *always* forgets to logout.  I want to 
have the system log her out when she leaves.  How can I do that?  (And don't 
tell me about the point-and-click user managing tool -- that is not going to 
work.)

-- 
Robert Heller             -- 978-544-6933
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