Question

When using a raw TCP socket, there is a need for doing message framing, as explained here, either with a length prefix, or with delimiters.

I came accross the “SOCK_SEQPACKET” socket option today, which could apparently do the message framing almost transparently.

What is the availability of “SOCK_SEQPACKET” amongst platforms and OSes at the moment? (Windows, OSX, Linux, IOS, Android…)

Answer 1

I you uses SOCK_SEQPACKET of AF_INET, this way:

socket(AF_INET, SOCK_SEQPACKET, 0); 

You won’t get a TCP socket. The socket will be a SCTP socket, if your platform supports it.

SCTP is not yet widely used. Latest Linux versions supports it (if SCTP is enabled).

There are some libraries also for Windows.