socketpair(2) -- Linux man page
NAMEsocketpair - create a pair of connected sockets
DESCRIPTIONThe socketpair call creates an unnamed pair of connected sockets in the specified domain d, of the specified type, and using the optionally specified protocol. The descriptors used in referencing the new sockets are returned in sv and sv. The two sockets are indistinguishable.
RETURN VALUEOn success, zero is returned. On error, -1 is returned, and errno is set appropriately.
- Too many descriptors are in use by this process.
- The specified address family is not supported on this machine.
- The specified protocol is not supported on this machine.
- The specified protocol does not support creation of socket pairs.
- The address sv does not specify a valid part of the process address space.
CONFORMING TO4.4BSD, SUSv2, POSIX 1003.1-2001. The socketpair function call appeared in 4.2BSD. It is generally portable to/from non-BSD systems supporting clones of the BSD socket layer (including System V variants).
NOTESOn Linux, the only supported domain for this call is AF_UNIX (or synonymously, AF_LOCAL). (Most implementations have the same restriction.)
SEE ALSOread(2), write(2), pipe(2), socket(2), unix(7)