//sys	Shutdown(s int, how int) (err error)

// In order to use msghdr structure with Control, Controllen in golang.org/x/net,
// nrecvmsg and nsendmsg must be used.
//sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error) = nrecvmsg
//sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error) = nsendmsg

func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {

//go:cgo_import_dynamic libc_recvfrom recvfrom "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_sendto sendto "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_Shutdown shutdown "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_nrecvmsg nrecvmsg "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_nsendmsg nsendmsg "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_accept accept "libc.a/shr_64.o"
//go:cgo_import_dynamic libc_Openat openat "libc.a/shr_64.o"

	}
}

// ReadMsg wraps the recvmsg network call.
func (fd *FD) ReadMsg(p []byte, oob []byte, flags int) (int, int, int, syscall.Sockaddr, error) {
	if err := fd.readLock(); err != nil {
		return 0, 0, 0, nil, err
	}
	defer fd.readUnlock()
	if err := fd.pd.prepareRead(fd.isFile); err != nil {
		return 0, 0, 0, nil, err
	}
	for {
		n, oobn, sysflags, sa, err := syscall.Recvmsg(fd.Sysfd, p, oob, flags)
		if err != nil {

func selectnbsend(hchan chan<- any, elem *any) bool
func selectnbrecv(elem *any, hchan <-chan any) (bool, bool)

func selectsetpc(pc *uintptr)
func selectgo(cas0 *byte, order0 *byte, pc0 *uintptr, nsends int, nrecvs int, block bool) (int, bool)
func block()

func makeslice(typ *byte, len int, cap int) unsafe.Pointer
func makeslice64(typ *byte, len int64, cap int64) unsafe.Pointer

			if sockType != SOCK_DGRAM {
				iov.Base = &dummy
				iov.SetLen(1)
			}
		}
		msg.Control = &oob[0]
		msg.SetControllen(len(oob))
	}
	msg.Iov = &iov
	msg.Iovlen = 1
	if n, err = recvmsg(fd, &msg, flags); err != nil {
		return
	}
	oobn = int(msg.Controllen)
	recvflags = int(msg.Flags)
	return
}