On 07 Aug 2014, at 23:08, Butler, Peter <pbutler@xxxxxxxxxxxx> wrote: > A question about using a SOCK_STREAM socket (one-to-one TCP-style) and checking for the MSG_EOR flag. > > If, on a given association (i.e. a single file descriptor, as per the one-to-one TCP-style SOCK_STREAM socket semantics), a message is received via sctp_recvmsg() with the MSG_EOR flag *not* set (such that more of the message is yet to be retrieved), does LKSCTP guarantee that the subsequent call to sctp_recvmsg() will still pertain to the same message (i.e. record)? > > That is, could the following message sequence (as returned by sctp_recvmsg(); not necessarily in this order on the wire) ever occur in subsequent calls to sctp_recvmsg() on the aforementioned file descriptor? > > MSG A, part 1 > MSG A, part 2 > MSG A, part 3 > MSG B > MSG A, part 4 > MSG A, part 5 (EOR) > . > . > . That would mean that you use the interleaving level 2 as specified in http://tools.ietf.org/html/rfc6458#section-8.1.20 > > Or will the kernel always guarantee the following: > > MSG A, part 1 > MSG A, part 2 > MSG A, part 3 > MSG A, part 4 > MSG A, part 5 (EOR) > MSG B > . > . > . That would be interleaving level 0 or 1, which are identical for SOCK_STREAM sockets. This should be the default. > > If the former is indeed possible, can the 'interleaving' only occur within separate streams of the association? Or can it also occur within a single given stream? Interleaving level 2 would allow this. Best regards Michael > > Can unordered data ever cause this to occur? > > -- > To unsubscribe from this list: send the line "unsubscribe linux-sctp" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-sctp" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
