XBT_PUBLIC(void) MSG_action_register(const char *action_name,
msg_action_fun function);
XBT_PUBLIC(void) MSG_action_unregister(const char *action_name);
XBT_PUBLIC(void) MSG_action_register(const char *action_name,
msg_action_fun function);
XBT_PUBLIC(void) MSG_action_unregister(const char *action_name);