DECnet Out-of-Band Data

DECnet supports the sending and receiving of OOB data through the MSG_OOB flag for recv and send. If a send with the MSG_OOB flag is sent, the recv must be posted with MSG_OOB in order to read the data. To check for the presence of OOB data, use select with exceptfds set, or a WSAASYNCSELECT with FD_OOB set.

DECnet does not support inline OOB data through the setsockopt SO_OOBINLINE flag.