Re: Bug or missing feature in who

[Andreas Schwab]

address@hidden (Bob Proulx) writes:

> Alexander Schestag wrote:
>> So, is there a way to tell "who" to list the users logged in via su
>> as well?
>
> Not with who.  AFAIK you would need to walk the process list for that
> information.  There is really nothing special about a login process.
> It is just a normal process.

Actually a login process is kind of special, because it creates a new
session and becomes the leader of it.  Changing the user with su, on the
other hand, does not create a new session (use ps -ej to display the
session id of every process).  Still, it is the sole responsibility of
the process creating the session to update the utmp/wtmp information.
In other words, you cannot trust this information in any way.

Andreas.

-- 
Andreas Schwab, SuSE Labs, address@hidden
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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