[Trisquel-users] Re : How to determine the cause of shutdown in a previous session?

[lcerf]

Now I’m thinking how can I turn off the PC off programmatically at the  
click of a button?

The default MATE desktop environment has an entry "Shut Down..." at the  
bottom of the main menu and you can add a button doing the same on any panel.  
 What desktop environment do you use?