(a) Sorry, I found no related category to post my questions; so, here!
(Please, relocate my post, if this category is inappropriate.)

………………………………

(b) Since:

- Gambas3 works (still "officially") on Linux,
- I am an LTSP (Linux Terminal Server Project) admin at the school I work,
- I am writing a Gambas3 program for use for LTSP admins (more on that, in ps1),

I had / have three questions, in order to finish it.

(1) How to remotely boot the terminals. (Answered! Found it! Done by installing the "wake-on-lan" script on the server, exporting the command through Gambas3, and ok.)
(2) How to remotely shut down / reboot the terminals, even if no user is logged in (ps 2). (Unanswered.)
(3) How to "export" the users on LAN, in case the user list changes; of course, terminals must first be shut down. (Unanswered.)

Have you guys either taken a look at LTSP as programmers, or just know the answers?

Thanks in advance!

ps1: When I "open" the greeter on terminals, the students see a full list of all the student names (and choose their own, to log in); I 'd like to have on the terminal greeters a list of just the very student Linux users (a dozen names, or less) at the very hour in the very lab - and that's what I program. (Of course GNU licence, of course will upload the source code here, after testing it!)
Well, if I "close" the greeter, everybody will just have to enter his/her user name and password, and that's all (since they don't know the user name of other students, to mess things up) - and my program is useless. But I think it might be of some importance (at least for some other admins), so I aim to finish it.

The idea is simple:
(1) sudo nano the ltsp.conf file, in order to group the users as [lab1], [lab2], etc,
(2) copy before each teaching hour the Linux group members of (real) classes / subclasses projected as Linux groups a1, a2, b1, b2, etc as members of group -say- labx,
(3) shut down the terminals, subtract the members of group labx, copy / add the new members for the next hour, export the new "initrd", then remotely boot the terminals; and then, every terminal greeter will be displaying the right users.

But programming is quite a tough (though pleasant with Gambas3) job! ;-) My work is still about 30% complete.

ps2: The "Epoptes" program (About - Epoptes - written in Python) does just that. I took a look at source code (https://github.com/epoptes/epoptes.git), but didn't understand where the crucial answers are located.

I would have put it in General topic. (no biggie though)

To be honest we are best suited to help with Gambas related questions.  (although someone may know the answers)

Your question may be better asked at a LTSP forum or chatroom

chat rooms are listed here…
Guides - Linux Terminal Server Project
Support - Linux Terminal Server Project

 Ok, the second question also already settled! It's as simple as that in Gambas3 (plus LTSP server installation, where the epoptes-client script is usually included) :

Exec ["epoptes-client", "-c", "shutdown"] Wait

It's simply a matter of (my free) time to finish the program. Then, I 'll upload the source code here for suggestions and improvements.

Thanks, again!