}
	// The kernel expects seconds so round to next highest second.
	secs := int(roundDurationUp(d, time.Second))
	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, sysTCP_KEEPIDLE, secs)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setKeepAliveInterval(fd *netFD, d time.Duration) error {
	if !unix.SupportTCPKeepAliveIdleIntvlCNT() {
		return syscall.EPROTOTYPE
	}

	if d == 0 {

	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setKeepAliveCount(fd *netFD, n int) error {
	if n == 0 {
		n = defaultTCPKeepAliveCount
	} else if n < 0 {
		return nil
	}

	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, sysTCP_KEEPCNT, n)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)

	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_RCVBUF, bytes)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setWriteBuffer(fd *netFD, bytes int) error {
	err := fd.pfd.SetsockoptInt(syscall.SOL_SOCKET, syscall.SO_SNDBUF, bytes)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setKeepAlive(fd *netFD, keepalive bool) error {

	err = fd.pfd.SetsockoptInet4Addr(syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, a)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setIPv4MulticastLoopback(fd *netFD, v bool) error {
	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v))
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)

	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)
}

func setKeepAliveCount(fd *netFD, n int) error {
	if n == 0 {
		n = defaultTCPKeepAliveCount
	} else if n < 0 {
		return nil
	}

	err := fd.pfd.SetsockoptInt(syscall.IPPROTO_TCP, syscall.TCP_KEEPCNT, n)
	runtime.KeepAlive(fd)
	return wrapSyscallError("setsockopt", err)

		return nil
	}
	err := fd.pfd.Shutdown(how)
	runtime.KeepAlive(fd)
	return wrapSyscallError("shutdown", err)
}

func (fd *netFD) Read(p []byte) (n int, err error) {
	if fd.fakeNetFD != nil {
		return fd.fakeNetFD.Read(p)
	}
	n, err = fd.pfd.Read(p)
	runtime.KeepAlive(fd)
	return n, wrapSyscallError(readSyscallName, err)
}

func (fd *netFD) Write(p []byte) (nn int, err error) {

	"internal/poll"
	"io"
	"syscall"
)

var (
	pollCopyFileRange = poll.CopyFileRange
	pollSplice        = poll.Splice
)

// wrapSyscallError takes an error and a syscall name. If the error is
// a syscall.Errno, it wraps it in an os.SyscallError using the syscall name.
func wrapSyscallError(name string, err error) error {
	if _, ok := err.(syscall.Errno); ok {
		err = NewSyscallError(name, err)
	}
	return err
}

//go:build unix || js || wasip1 || windows

package net

import (
	"os"
	"syscall"
)

// wrapSyscallError takes an error and a syscall name. If the error is
// a syscall.Errno, it wraps it in an os.SyscallError using the syscall name.
func wrapSyscallError(name string, err error) error {
	if _, ok := err.(syscall.Errno); ok {
		err = os.NewSyscallError(name, err)
	}
	return err

			return 0, nil, false
		}
		s = v.fd
	default:
		return 0, nil, false
	}

	written, handled, err = pollSplice(&c.pfd, &s.pfd, remain)
	if lr != nil {
		lr.N -= written
	}
	return written, wrapSyscallError("splice", err), handled
}

// spliceTo transfers data from c to w using the splice system call to minimize
// copies from and to userspace. c must be a TCP connection.

	}
	return n, nil
}

func (fd *netFD) writeBuffers(v *Buffers) (n int64, err error) {
	n, err = fd.pfd.Writev((*[][]byte)(v))
	runtime.KeepAlive(fd)
	return n, wrapSyscallError("writev", err)