[Samba] Get number of current logged on users

[Ari Constancio]

Hi,

I'm looking for a simple way to get the number of current logged on
users (with established sessions) to measure the use frequency of our
student labs. I don't need to identify the users.

I haven't found anything useful yet. So I'm asking here for some
advice before getting myself hacking my own scripts :).

Thanks in advance,
Ari Constancio