socketpair(3N)                   UNIX System V                   socketpair(3N)


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) in the Programmer's Reference Manual

NOTES
      This call is currently implemented only for the AFUNIX address family.









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