Hi Didier,

Didier Kryn writes:
>     My first investigations indicate that there is provision in
> Freedesktop.org to put icons and launchers under $HOME/.local, but
> nothing for /usr/local.

I do not think that ~/.local is related to /usr/local in any meaningfull
way. /usr/local is for the administrator to put self-compiled stuff
there, stuff that should be avaiable for all accounts on the machine.
Used to be, that in some environments that directory was on a network
share, so these packages were immediatly available on all machines in
the local network.

>     Seems /usr/local is honoured by the base system (default PATH and
> default man search path) but is "deprecated" by Freedesktop.

The distribution package manager and its packages have no business
installing anything there, so there is nothing to deprecate. That the
default install add /usr/local/bin to PATH and similarly for other
directories is just a convenience. Some of the BSDs do not do that
IIRC.

> Therefore the installation of an application in /usr/local could
> include executable, config files and manpages, but the icon and the
> launcher would be per user.

Icon pictures can be in /usr/local. XDG desktop files (which make the
applications show up in the Gnome shell and other DEs) can be installed
in /etc/xdg, like the packages from the package manager do. It is
possible that Gnome/XDG also looks into /usr/local/etc/xdg or some
similar place in addition to /etc/xdg, I haven't checked.

/etc is used both by distribution packages and by packages in
/usr/local. Only distribution packages should install default
configurations there, and only if those files did not exist before or,
during an update, if they where not modified since installation or last
update.

When the user changes stuff in the desktop files (managing autostarts,
hiding applications), those changes go into copies of the files in
~/.local. Gnome sees those files as overrides, as long as they have the
same name. When the user installs applications for himself (e.g. using
xdg-desktop-icon), those desktop files also go there.

> to my knowledge, there is no default user directory for executables;

In some distibutions /etc/profile adds ~/bin to PATH, if it exists.
Again this is just a convenience. In the end /etc is for the
administrator to set her/his own policy.

so long, benny