一个VC简单的UDP广播示例

最新推荐文章于 2024-08-06 15:15:29 发布

yunjinwang

最新推荐文章于 2024-08-06 15:15:29 发布

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分类专栏：网络文章标签： socket struct null winapi list thread

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本文提供了一个使用VC实现的UDP广播示例，包括接收端和发送端的代码。接收端通过创建线程监听特定端口，接收到广播消息后打印出来。发送端则设置套接字为广播类型，向网络上的广播地址发送消息。

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接收端：

#include<stdlib.h>

//#include<iostream.h>

#include<conio.h>

#include<stdio.h>

#include<winsock2.h>

#include<windows.h>

#pragma comment (lib, "ws2_32.lib")

HANDLE hr,hl,hbusy;

struct thrpar

{

SOCKET s;

};

struct recpar

{

SOCKET srec;

struct sockaddr_in addr;

};

UINT recthread(LPVOID pp)

{

SOCKET srec,s2;

struct recpar *prec=(struct recpar *)pp;

sockaddr_in recaddr;

srec=prec->srec;

recaddr=prec->addr;

char buf[256];

DWORD ret;

printf("recv thread start!");

ret=recv(srec,buf,256,0);

if(ret==0)

{

printf("connect close!");

closesocket(srec);

return 0;

}

else if(ret==SOCKET_ERROR)

{

printf("connect error!");

closesocket(srec);

return 0;

}

printf("recv data:%s",buf);

return 0;

}

DWORD WINAPI listhread(LPVOID pp)

{

::MessageBox(NULL,"enter the listhread","KK",MB_OK);

struct thrpar *pthr=(struct thrpar*)pp;

SOCKET sl,saccept;

sockaddr_in here, there;

char name[256];

struct hostent *phost;

int ret;

gethostname(name,256);

phost=gethostbyname(name);

here.sin_family=AF_INET;

here.sin_port=htons(1024);

here.sin_addr.S_un.S_un_b.s_b1=phost->h_addr_list[0][0];

here.sin_addr.S_un.S_un_b.s_b2=phost->h_addr_list[0][1];

here.sin_addr.S_un.S_un_b.s_b3=phost->h_addr_list[0][2];

here.sin_addr.S_un.S_un_b.s_b4=phost->h_addr_list[0][3];

sl=pthr->s;

ret=bind(sl,(struct sockaddr *)&here,sizeof(here));

if(ret!=0)

{

printf("bind error");

return 0;

}

ret=listen(sl,5);

if(ret!=0)

{

printf("listen error");

return 0;

}

while(true)

{

int nlen=sizeof(there);

saccept=accept(sl,(struct sockaddr *)&there,&nlen);

if(saccept==INVALID_SOCKET)

{

printf("accept socket invalid");

}

DWORD wret=WaitForSingleObject(hbusy,500);

if(wret==WAIT_TIMEOUT)

{

send(saccept,"\0",1,0);

closesocket(saccept);

continue ;

}

DWORD recid;

struct recpar *prec;

prec->addr=there;

prec->srec=saccept;

hr=CreateThread(NULL,0,(LPTHREAD_START_ROUTINE)&listhread,prec,0,&recid);

return 1;

}

return 1;

}

void main(void)

{

SOCKET s;

sockaddr_in addrin;

WSADATA wsdata;

BOOL bsocket;

char *smsg="this is a test";

WSAStartup(0x0202,&wsdata);

s=WSASocket(AF_INET,SOCK_STREAM,0,NULL,0,WSA_FLAG_OVERLAPPED);

hbusy=CreateSemaphore(NULL,0,2,NULL);

struct thrpar *psc;

psc=new struct thrpar;

DWORD lisid;

psc->s=s;

hr=CreateThread(NULL,0,listhread,psc,0,&lisid);

DWORD ret=WaitForSingleObject(hr,10000);

if(ret==WAIT_OBJECT_0)printf("thread time out%d\r\n",lisid);

}*/

void main(void )

{

SOCKET s;

sockaddr_in from,a;

WSADATA wsdata;

BOOL optval;

//启?动??SOCKET库a，??版??本??为a2.0

WSAStartup(0x0202,&wsdata);

optval=TRUE;

//然??后??赋3值??给?两??个?地??址??，??一??个?用??来???绑???定??套???接??字??，??一??个?用??来???从???网??络?上??的??广?播??地??址??接??收??消?息??；??

a.sin_family=AF_INET;

a.sin_addr.s_addr=0;

a.sin_port=htons(5050);

from.sin_family=AF_INET;

from.sin_addr.s_addr=INADDR_BROADCAST;

from.sin_port=htons(5050);

int fromlength=sizeof (SOCKADDR);

//用??UDP初?始??化??套???接??字??

s=socket(AF_INET,SOCK_DGRAM,0);

//设???置?该?套???接??字??为a广?播??类???型??，??

setsockopt(s,SOL_SOCKET,SO_BROADCAST,( char FAR *)&optval,sizeof (optval));

bind(s,(sockaddr *)&a, sizeof(sockaddr_in));

char buf[256];

while(1)

{ //从???广?播??地??址??接??收??消?息??，??注???意?a用??来???绑???定??的??地??址??和??接??收??消?息??的??地??址??是??不?一??样??的??

recvfrom(s,buf,256,0,( struct sockaddr FAR *)&from,(int FAR *)&fromlength);

Sleep(2000);

printf( "%s\n",buf);

ZeroMemory(buf,256);

}

发送端：

#include<stdlib.h>

//#include<iostream.h>

#include<stdio.h>

#include<conio.h>

#include<winsock2.h>

#include<windows.h>

#pragma comment (lib, "ws2_32.lib")

int main()

{

SOCKET s;

sockaddr_in addrto;

WSADATA wsdata;

BOOL bsocket;

char *smsg="this is a test wyj" ;

//启?动??SOCKET库a，??版??本??为a2.0

WSAStartup(0x0202,&wsdata);

s=WSASocket(AF_INET,SOCK_DGRAM,0,NULL,0,WSA_FLAG_OVERLAPPED);

bsocket=TRUE;

//然??后??赋3值??给?地??址??，??用??来???从???网??络?上??的??广?播??地??址??接??收??消?息??；??

addrto.sin_family=AF_INET;

addrto.sin_addr.s_addr=INADDR_BROADCAST;

addrto.sin_port=htons(5050);

bool opt=true ;

//设???置?该?套???接??字??为a广?播??类???型??，??

setsockopt(s,SOL_SOCKET,SO_BROADCAST,( char FAR *)&opt,sizeof (opt));

int nlen=sizeof (addrto);

while(1)

{

Sleep(1000);

//从???广?播??地??址??发???送??消?息??

int ret=sendto(s,smsg,strlen(smsg),0,(sockaddr*)&addrto,nlen);

if(ret==SOCKET_ERROR)

printf( "Error:%s\n", WSAGetLastError());

else

{

printf( "ok");

}

return -1;

}