When Emacs exits, it terminates all its subprocesses. For
subprocesses that run a program, it sends them the
signal; connections are simply closed. Because subprocesses may be
doing valuable work, Emacs normally asks the user to confirm that it
is ok to terminate them. Each process has a query flag, which, if
nil, says that Emacs should ask for confirmation before
exiting and thus killing that process. The default for the query flag
t, meaning do query.
This function sets the query flag of process to flag. It returns flag.
Here is an example of using
set-process-query-on-exit-flagon a shell process to avoid querying:(set-process-query-on-exit-flag (get-process "shell") nil) ⇒ nil