getPeerCredentials
Gets the credentials of the authenticated peer. This will always return null unless @connection acted as a server (e.g. %G_DBUS_CONNECTION_FLAGS_AUTHENTICATION_SERVER was passed) when set up and the client passed credentials as part of the authentication process.
In a message bus setup, the message bus is always the server and each application is a client. So this method will always return null for message bus clients.
Return
a #GCredentials or null if not available. Do not free this object, it is owned by @connection.
Since
2.26