GSettings questions

[Pierre <pwieser trychlos org>]

Hi all,

About preferences management with GSettings, is someone able to tell me
if it would be possible for an administrator to define some system-wide value 
for
some setting ? And how ?
[1] indicates that a mandatory value is possible with GSettings, but I did not 
found
any corresponding API in [2].

And, when reading a value from GSettings, how do we know if this value has been
setup by an admin or is a user value ? Because in the first case, the value 
should
be read-only, and the reason for why it is read-only should be displayed to the
user...

[1] http://library.gnome.org/devel/gio/2.27/ch28.html
[2] http://library.gnome.org/devel/gio/stable/GSettings.html

Thanks in advance for any help

Regards
Pierre