github.com/xushiwei/go@v0.0.0-20130601165731-2b9d83f45bc9/src/pkg/net/sockopt_bsd.go (about) 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 // +build darwin freebsd netbsd openbsd 6 7 // Socket options for BSD variants 8 9 package net 10 11 import ( 12 "os" 13 "syscall" 14 ) 15 16 func setDefaultSockopts(s, f, t int, ipv6only bool) error { 17 switch f { 18 case syscall.AF_INET6: 19 if ipv6only { 20 syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, 1) 21 } else { 22 // Allow both IP versions even if the OS default 23 // is otherwise. Note that some operating systems 24 // never admit this option. 25 syscall.SetsockoptInt(s, syscall.IPPROTO_IPV6, syscall.IPV6_V6ONLY, 0) 26 } 27 } 28 // Allow broadcast. 29 err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_BROADCAST, 1) 30 if err != nil { 31 return os.NewSyscallError("setsockopt", err) 32 } 33 return nil 34 } 35 36 func setDefaultListenerSockopts(s int) error { 37 // Allow reuse of recently-used addresses. 38 err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1) 39 if err != nil { 40 return os.NewSyscallError("setsockopt", err) 41 } 42 return nil 43 } 44 45 func setDefaultMulticastSockopts(s int) error { 46 // Allow multicast UDP and raw IP datagram sockets to listen 47 // concurrently across multiple listeners. 48 err := syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEADDR, 1) 49 if err != nil { 50 return os.NewSyscallError("setsockopt", err) 51 } 52 // Allow reuse of recently-used ports. 53 // This option is supported only in descendants of 4.4BSD, 54 // to make an effective multicast application that requires 55 // quick draw possible. 56 err = syscall.SetsockoptInt(s, syscall.SOL_SOCKET, syscall.SO_REUSEPORT, 1) 57 if err != nil { 58 return os.NewSyscallError("setsockopt", err) 59 } 60 return nil 61 }