socketpair(2) — Linux manual page

socketpair(2)              System Calls Manual              socketpair(2)

NAME         top

       socketpair - create a pair of connected sockets

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <sys/socket.h>

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

DESCRIPTION         top

       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 file descriptors used in referencing the new sockets are
       returned in sv[0] and sv[1].  The two sockets are
       indistinguishable.

RETURN VALUE         top

       On success, zero is returned.  On error, -1 is returned, errno is
       set to indicate the error, and sv is left unchanged

       On Linux (and other systems), socketpair() does not modify sv on
       failure.  A requirement standardizing this behavior was added in
       POSIX.1-2008 TC2.

ERRORS         top

       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 The per-process limit on the number of open file
              descriptors has been reached.

       ENFILE The system-wide 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.

VERSIONS         top

       On Linux, the only supported domains for this call are AF_UNIX (or
       synonymously, AF_LOCAL) and AF_TIPC (since Linux 4.12).

STANDARDS         top

       POSIX.1-2008.

HISTORY         top

       POSIX.1-2001, 4.4BSD.

       socketpair() first appeared in 4.2BSD.  It is generally portable
       to/from non-BSD systems supporting clones of the BSD socket layer
       (including System V variants).

       Since Linux 2.6.27, socketpair() supports the SOCK_NONBLOCK and
       SOCK_CLOEXEC flags in the type argument, as described in
       socket(2).

SEE ALSO         top

       pipe(2), read(2), socket(2), write(2), socket(7), unix(7)

COLOPHON         top

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Linux man-pages 6.10            2024-07-23                  socketpair(2)

Pages that refer to this page: pipe(2),  socket(2),  socketcall(2),  syscalls(2),  sockaddr(3type),  fifo(7),  pipe(7),  signal-safety(7),  socket(7),  unix(7)

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