gobject:signal-name (id)

id -- an unsigned integer with the identifying number of the signal

The string with the signal name, or nil if the signal number was invalid.

Given the identifier of the signal, finds its name. Two different signals may have the same name, if they have differing types. Get the signal ID for the "startup" signal and then get the name for the ID:

(g:signal-lookup "startup" "GApplication")
=> 95
(g:signal-name *)
=> "startup"    

List the IDs for an application object and retrieves the names of the signals:

(g:signal-list-ids "GApplication")
=> (97 95 96 98 99 100 101)
(mapcar #'g:signal-name *)
=> ("activate" "startup" "shutdown" "open" "command-line"
    "handle-local-options" "name-lost")