+Under Unix the flag {\tt wxEXEC\_MAKE\_GROUP\_LEADER} may be used to ensure
+that the new process is a group leader (this will create a new session if
+needed). Calling \helpref{wxKill}{wxkill} with the argument of -pid where pid
+is the process ID of the new process will kill this process as well as all of
+its children (except those which have started their own session).
+