socketpair

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  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.

RETURN VALUE

       On  success,  zero is returned.  On error, -1 is returned,
       and errno is set appropriately.

ERRORS

       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.

HISTORY

       The socketpair function call appeared in BSD 4.2.

BUGS

       This call is  currently  implemented  only  for  the  UNIX
       domain.  [Documenter's note: is this true for Linux?]

SEE ALSO

       read(2), write(2), pipe(2)