NAME

socketpair − create a pair of connected sockets

SYNOPSIS

#include <sys/types.h>
#include <sys/socket.h>

int socketpair(int d, int type, int protocol, int sv[2]);

DESCRIPTION

The socketpair library call creates an unnamed pair of connected sockets in the specified address family 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. 

RETURN VALUE

socketpair returns a −1 on failure, otherwise it returns the number of the second file descriptor it creates. 

ERRORS

The call succeeds unless:

EMFILE Too many descriptors are in use by this process. 

EAFNOSUPPORT The specified address family is not supported on this machine. 

EPROTONOSUPPORT
The specified protocol is not supported on this machine.

EOPNOSUPPORT The specified protocol does not support creation of socket pairs. 

ENOMEM There was insufficient user memory for the operation to complete. 

ENOSR There were insufficient STREAMS resources for the operation to complete. 

SEE ALSO

pipe(2), read(2), write(2). 

NOTES

This call is currently implemented only for the AF_UNIX address family.