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.\" @(#)socketpair.2 6.4 (Berkeley) 3/10/91
.Nd create a pair of connected sockets
.Fd #include <sys/types.h>
.Fd #include <sys/socket.h>
.Fn socketpair "int d" "int type" "int protocol" "int *sv"
call creates an unnamed pair of connected sockets in
and using the optionally specified
The descriptors used in referencing the new sockets
The two sockets are indistinguishable.
A 0 is returned if the call succeeds, -1 if it fails.
The call succeeds unless:
.Bl -tag -width EPROTONOSUPPORTA
Too many descriptors are in use by this process.
The specified address family is not supported on this machine.
.It Bq Er EPROTONOSUPPORT
The specified protocol is not supported on this machine.
The specified protocol does not support creation of socket pairs.
does not specify a valid part of the
This call is currently implemented only for the
function call appeared in