UDP.rar_udp 服务器

/*客户端程序代码：先建立一个UDP套接字，然后使用循环将命令行传进来的字符串通过UDP套接字依次传送给服务器*/ #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()*/ #include<sys/time.h> /*select()*/ #define REMOTE_SERVER_PORT 1500 #define MAX_MSG 100 int main(int argc,char *argv[]){ int sd,rc,i; struct sockaddr_in cliAddr,remoteServAddr; struct hostent *h; /*check command line args*/ if(argc<3){ printf("usage:%s <server><data1>...<data N>\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:unkonwn 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=htos(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); } /*send data*/ for(i=2;i<argc;i++){ rc=sendto(sd,argv[i],strlen(argv[i]+1),0,()); } }