-/* Try parsing "msg" into a command to apply, and apply it. Output commands to
- * stdout if "do_verbose" and world.is_verbose are set. If "do_record" is set,
- * record commands to record file, and run save_world() if the last call to it
- * via this function has not happened yet or is at least one minute in the past.
+/* Try parsing "msg" into a command to apply. Output "msg" if world.is_verbose.
+ * If "obey_state" is > 1 and world.replay is set, any non-meta command message
+ * is not executed, but merely returns 3. The QUIT meta command (if well-formed)
+ * always returns 2. Other meta commands and (with "obey_state" < 2) non-meta
+ * commands return 1 if well-formed. Malformed or empty command messages return
+ * 0. If "obey_state" is 1, "msg" is recorded via a non-forced record(). If a
+ * non-meta command is executed and world.exists, world.do_update is set.