github.com/code-reading/golang@v0.0.0-20220303082512-ba5bc0e589a3/go/src/net/tcpsockopt_windows.go (about)

     1  // Copyright 2009 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package net
     6  
     7  import (
     8  	"os"
     9  	"runtime"
    10  	"syscall"
    11  	"time"
    12  	"unsafe"
    13  )
    14  
    15  func setKeepAlivePeriod(fd *netFD, d time.Duration) error {
    16  	// The kernel expects milliseconds so round to next highest
    17  	// millisecond.
    18  	msecs := uint32(roundDurationUp(d, time.Millisecond))
    19  	ka := syscall.TCPKeepalive{
    20  		OnOff:    1,
    21  		Time:     msecs,
    22  		Interval: msecs,
    23  	}
    24  	ret := uint32(0)
    25  	size := uint32(unsafe.Sizeof(ka))
    26  	err := fd.pfd.WSAIoctl(syscall.SIO_KEEPALIVE_VALS, (*byte)(unsafe.Pointer(&ka)), size, nil, 0, &ret, nil, 0)
    27  	runtime.KeepAlive(fd)
    28  	return os.NewSyscallError("wsaioctl", err)
    29  }