UDP Client Server Echo Example
来源:互联网 发布:孩子 知乎 编辑:程序博客网 时间:2024/05/01 07:56
Here's an example UDP echo server I created from a simple UDP example (originally to help another thread question, now solved). Additionally, it shows how to use select() to poll the socket (with an optional time out).
Compiled and tested on and between Win32/Cygwin and Linux (would need to be modified for Win32/Winsock).
Compile:
gcc -Wall -o client udpClient.c
gcc -Wall -o server udpServer.c
Run:
./server&
./client 127.0.0.1 this is a test.
(or run server in another console, separate machines, etc.).
Client:
/* fpont 12/99 */
/* pont.net */
/* udpClient.c */
/* Converted to echo client/server with select() (timeout option) */
/* 3/30/05 John Schultz */
#include <stdlib.h> /* for exit() */
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h> /* memset() */
#include <sys/time.h> /* select() */
#define REMOTE_SERVER_PORT 1500
#define MAX_MSG 100
/* BEGIN jcs 3/30/05 */
#define SOCKET_ERROR -1
int isReadable(int sd,int * error,int timeOut) { // milliseconds
fd_set socketReadSet;
FD_ZERO(&socketReadSet);
FD_SET(sd,&socketReadSet);
struct timeval tv;
if (timeOut) {
tv.tv_sec = timeOut / 1000;
tv.tv_usec = (timeOut % 1000) * 1000;
} else {
tv.tv_sec = 0;
tv.tv_usec = 0;
} // if
if (select(sd+1,&socketReadSet,0,0,&tv) == SOCKET_ERROR) {
*error = 1;
return 0;
} // if
*error = 0;
return FD_ISSET(sd,&socketReadSet) != 0;
} /* isReadable */
/* END jcs 3/30/05 */
int main(int argc, char *argv[]) {
int sd, rc, i, n, echoLen, flags, error, timeOut;
struct sockaddr_in cliAddr, remoteServAddr, echoServAddr;
struct hostent *h;
char msg[MAX_MSG];
/* check command line args */
if(argc<3) {
printf("usage : %s <server> <data1> ... <dataN> /n", argv[0]);
exit(1);
}
/* get server IP address (no check if input is IP address or DNS name */
h = gethostbyname(argv[1]);
if(h==NULL) {
printf("%s: unknown host '%s' /n", argv[0], argv[1]);
exit(1);
}
printf("%s: sending data to '%s' (IP : %s) /n", argv[0], h->h_name,
inet_ntoa(*(struct in_addr *)h->h_addr_list[0]));
remoteServAddr.sin_family = h->h_addrtype;
memcpy((char *) &remoteServAddr.sin_addr.s_addr,
h->h_addr_list[0], h->h_length);
remoteServAddr.sin_port = htons(REMOTE_SERVER_PORT);
/* socket creation */
sd = socket(AF_INET,SOCK_DGRAM,0);
if(sd<0) {
printf("%s: cannot open socket /n",argv[0]);
exit(1);
}
/* bind any port */
cliAddr.sin_family = AF_INET;
cliAddr.sin_addr.s_addr = htonl(INADDR_ANY);
cliAddr.sin_port = htons(0);
rc = bind(sd, (struct sockaddr *) &cliAddr, sizeof(cliAddr));
if(rc<0) {
printf("%s: cannot bind port/n", argv[0]);
exit(1);
}
/* BEGIN jcs 3/30/05 */
flags = 0;
timeOut = 100; // ms
/* END jcs 3/30/05 */
/* send data */
for(i=2;i<argc;i++) {
rc = sendto(sd, argv[i], strlen(argv[i])+1, flags,
(struct sockaddr *) &remoteServAddr,
sizeof(remoteServAddr));
if(rc<0) {
printf("%s: cannot send data %d /n",argv[0],i-1);
close(sd);
exit(1);
}
/* BEGIN jcs 3/30/05 */
/* init buffer */
memset(msg,0x0,MAX_MSG);
while (!isReadable(sd,&error,timeOut)) printf(".");
printf("/n");
/* receive echoed message */
echoLen = sizeof(echoServAddr);
n = recvfrom(sd, msg, MAX_MSG, flags,
(struct sockaddr *) &echoServAddr, &echoLen);
if(n<0) {
printf("%s: cannot receive data /n",argv[0]);
continue;
}
/* print received message */
printf("%s: echo from %s:UDP%u : %s /n",
argv[0],inet_ntoa(echoServAddr.sin_addr),
ntohs(echoServAddr.sin_port),msg);
/* END jcs 3/30/05 */
}
return 1;
}
Server:
/* fpont 12/99 */
/* pont.net */
/* udpServer.c */
/* Converted to echo client/server with select() (timeout option). See udpClient.c */
/* 3/30/05 John Schultz */
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <netdb.h>
#include <stdio.h>
#include <unistd.h> /* close() */
#include <string.h> /* memset() */
#define LOCAL_SERVER_PORT 1500
#define MAX_MSG 100
int main(int argc, char *argv[]) {
int sd, rc, n, cliLen, flags;
struct sockaddr_in cliAddr, servAddr;
char msg[MAX_MSG];
/* socket creation */
sd=socket(AF_INET, SOCK_DGRAM, 0);
if(sd<0) {
printf("%s: cannot open socket /n",argv[0]);
exit(1);
}
/* bind local server port */
servAddr.sin_family = AF_INET;
servAddr.sin_addr.s_addr = htonl(INADDR_ANY);
servAddr.sin_port = htons(LOCAL_SERVER_PORT);
rc = bind (sd, (struct sockaddr *) &servAddr,sizeof(servAddr));
if(rc<0) {
printf("%s: cannot bind port number %d /n",
argv[0], LOCAL_SERVER_PORT);
exit(1);
}
printf("%s: waiting for data on port UDP %u/n",
argv[0],LOCAL_SERVER_PORT);
/* BEGIN jcs 3/30/05 */
flags = 0;
/* END jcs 3/30/05 */
/* server infinite loop */
while(1) {
/* init buffer */
memset(msg,0x0,MAX_MSG);
/* receive message */
cliLen = sizeof(cliAddr);
n = recvfrom(sd, msg, MAX_MSG, flags,
(struct sockaddr *) &cliAddr, &cliLen);
if(n<0) {
printf("%s: cannot receive data /n",argv[0]);
continue;
}
/* print received message */
printf("%s: from %s:UDP%u : %s /n",
argv[0],inet_ntoa(cliAddr.sin_addr),
ntohs(cliAddr.sin_port),msg);
/* BEGIN jcs 3/30/05 */
sleep(1);
sendto(sd,msg,n,flags,(struct sockaddr *)&cliAddr,cliLen);
/* END jcs 3/30/05 */
}/* end of server infinite loop */
return 0;
}
- UDP Client Server Echo Example
- C socket TCP/UDP client/server example codes
- ECHO TCP Server Client
- 回射客户端服务器UDP(echo client&&server based on UDP)
- simple select echo server example
- simple poll echo server example
- twisted-01 Echo server and echo client
- Socket tips: UDP Echo service - Client code
- Python UDP Server Client
- UDP server,client 代码
- UDP Server/Client
- 5-TCP Client&Server Example
- 19. 17. 1. UDP客户端响应 UDP Echo Client
- 采用epoll实现echo server和client
- java 多线程Echo server和client 例子
- libevent for echo server and client
- libevent for echo server and client
- epoll实现echo server和client
- 浅谈HTTP中Get与Post的区别
- 软件开发过程犹如开车自驾游。
- Show multiple tables in one page by using valueList
- TiddlyWiki 使用基本语法
- 细品RibbonX(9):层次分明的RibbonX代码结构
- UDP Client Server Echo Example
- nslookup用法
- php中调用其他系统http接口的方法
- 工作效率
- 如何用代码对Excel的指定区域实行保护
- url重写小例子
- linux 上网
- DWR使用笔记
- 全中文日期显示