XBT_PUBLIC void* MSG_process_get_data(msg_process_t process);
XBT_PUBLIC msg_error_t MSG_process_set_data(msg_process_t process, void* data);
XBT_PUBLIC void* MSG_process_get_data(msg_process_t process);
XBT_PUBLIC msg_error_t MSG_process_set_data(msg_process_t process, void* data);