Is there any difference between socketpair and pair of unnamed pipes?

Question

I would like to know not only user-side differences, but differences / common parts in Linux kernel implementation as well.

Answer 1

• pipes are unidirectional, so you need two pipes to have bidirectional communication, whereas a socketpair is bidirectional.

• pipes are always stream-oriented, whereas socketpairs can be datagram-oriented.

• socketpairs are normal AF_UNIX sockets, which means that ancillary messages like SCM_RIGHTS and SCM_CREDENTIALS can be passed over them.

In the kernel, pipes are implemented in the filesystem code and socketpairs in the networking code.