int socketpair(int domain, int type, int protocol, int sv[2]);
DESCRIPTION
The
socketpair()
call creates an unnamed pair of connected sockets in the specified
domain,
of the specified
type,
and using the optionally specified
protocol.
For further details of these arguments, see
socket(2).
The descriptors used in referencing the new sockets are returned in
sv[0]
and
sv[1].
The two sockets are indistinguishable.
RETURN VALUE
On success, zero is returned.
On error, -1 is returned, and
errno
is set appropriately.
ERRORS
EAFNOSUPPORT
The specified address family is not supported on this machine.
EFAULT
The address
sv
does not specify a valid part of the process address space.
EMFILE
Too many descriptors are in use by this process.
ENFILE
The system limit on the total number of open files has been reached.
EOPNOTSUPP
The specified protocol does not support creation of socket pairs.
EPROTONOSUPPORT
The specified protocol is not supported on this machine.
CONFORMING TO
4.4BSD, POSIX.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).
NOTES
On Linux, the only supported domain for this call is
AF_UNIX
(or synonymously,
AF_LOCAL).
(Most implementations have the same restriction.)
Since Linux 2.6.27,
socketpair()
supports the
SOCK_NONBLOCK
and
SOCK_CLOEXEC
flags described in
socket(2).
POSIX.1-2001 does not require the inclusion of
<sys/types.h>,
and this header file is not required on Linux.
However, some historical (BSD) implementations required this header
file, and portable applications are probably wise to include it.
This page is part of release 3.14 of the Linux
man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
