socketpair - create a pair of connected sockets
int socketpair(int d, int type, int protocol, int sv[2?);
The 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[0? and sv[1?. The two sockets are indistinguishable.
The domain is a protocol family, such as AF_UNIX (see unix(7)), the type is a type of socket, such as SOCK_STREAM, SOCK_SEQPACKET or SOCK_DGRAM.
On success, zero is returned. On error, -1 is returned, and errno is set appropriately.
- Too many descriptors are in use by this process.
- Not enough file descriptors available system wide.
- 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.
- Insufficient memory was available to fulfill the request.
- Insufficient resources were available in the system to perform the operation.
- Permission denied (Documented by POSIX)
4.4BSD (the socketpair function call appeared in 4.2BSD). Generally portable to/from non-BSD systems supporting clones of the BSD socket layer (including System
read(2), write(2), pipe(2)