SOCKETPAIR(2)             386BSD Programmer's Manual             SOCKETPAIR(2)

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)

DESCRIPTION
     The 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[0] and sv[1]. The two sockets are indistinguishable.

DIAGNOSTICS
     A 0 is returned if the call succeeds, -1 if it fails.

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.

     [EFAULT]          The address sv does not specify a valid part of the
                       process address space.

SEE ALSO
     read(2),  write(2),  pipe(2)

BUGS
     This call is currently implemented only for the UNIX domain.

HISTORY
     The socketpair function call appeared in 4.2BSD.

4.2 Berkeley Distribution       March 10, 1991                               1