1 // Copyright 2011 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 "unsafe" 12 ) 13 14 func setIPv4MulticastInterface(fd *netFD, ifi *Interface) error { 15 ip, err := interfaceToIPv4Addr(ifi) 16 if err != nil { 17 return os.NewSyscallError("setsockopt", err) 18 } 19 var a [4]byte 20 copy(a[:], ip.To4()) 21 err = fd.pfd.Setsockopt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_IF, (*byte)(unsafe.Pointer(&a[0])), 4) 22 runtime.KeepAlive(fd) 23 return wrapSyscallError("setsockopt", err) 24 } 25 26 func setIPv4MulticastLoopback(fd *netFD, v bool) error { 27 err := fd.pfd.SetsockoptInt(syscall.IPPROTO_IP, syscall.IP_MULTICAST_LOOP, boolint(v)) 28 runtime.KeepAlive(fd) 29 return wrapSyscallError("setsockopt", err) 30 } 31
