On 2024-06-03 07:17, Mark J. Reed wrote:
> The *exec* builtin replaces the running shell with whatever program 
> you run.  The point is to avoid clogging the process table with shells 
> that are just hanging out waiting to do nothing but exit as soon as 
> their child process finishes.
I get that.

>
> In your case, the script exists to set things up in the environment 
> and then run xfce4-session; there's nothing for it to do after 
> xfce4-session completes, so it uses *exec* to tidy up.

Sure.  But then what? I understand that if a script or function has 
nothing more to do, it may as well pre-kill itself. But the difference 
is that 'exec' kills the entire terminal, it doesn't just return to the 
prompt in a more efficient way -- which would be easy to understand, as 
above.  exec seems to pull the rug out from under itself, not just end a 
script more efficiently.  In my case, from what I've heard control seems 
to pass to dbus.  Mind, if dbus called the script then that's what one 
might expect.