Le jeu. 27 août 2020 à 18:02, Alfred M. Szmidt <ams@gnu.org> a écrit :
Is it possible to detect between remote and non-remote?

For buffers associated to files, there is file-remote-p. 
For others, stackoverflow suggests using (file-remote-p default-directory).

I don't know how those behave if you use tramp to connect to a server which 
then connects to the local host, or whether one using such connections would
not want that information to be as clearly visible as a remote host.