SD_HOST_LEVEL = xbt_lib_add_level(host_lib,__SD_workstation_destroy);
SD_LINK_LEVEL = xbt_lib_add_level(link_lib,__SD_link_destroy);
SD_STORAGE_LEVEL = xbt_lib_add_level(storage_lib,__SD_storage_destroy);
SD_HOST_LEVEL = xbt_lib_add_level(host_lib,__SD_workstation_destroy);
SD_LINK_LEVEL = xbt_lib_add_level(link_lib,__SD_link_destroy);
SD_STORAGE_LEVEL = xbt_lib_add_level(storage_lib,__SD_storage_destroy);