socket 聊天室实现

server

#include <stdio.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>

void handler(int sig)
{
        printf("recv a sig=%d\n",sig);
        exit();
}

int main(void)
{
        int listenfd;
        listenfd = socket(PF_INET,SOCK_STREAM,);
        if(listenfd < )
        {
                printf("creat socket failed\n");
                exit();
        }
        struct sockaddr_in servaddr;
        memset(&servaddr,,sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons();
        servaddr.sin_addr.s_addr = htonl(INADDR_ANY);//host any address

        int n=;
        if(setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&n,sizeof(n))<)
        {
                printf("set resueaddr failed\n");
                exit();
         }

        if(bind(listenfd,(struct sockaddr*)&servaddr,sizeof(servaddr))<)
        {
                printf("bind fialed\n");
                exit();
        }
        if(listen(listenfd,SOMAXCONN)<)
        {
                printf("listen failed\n");
                exit();
        }
        struct sockaddr_in peeraddr;
        socklen_t peerlen = sizeof(peeraddr);
        int conn;
        if((conn=accept(listenfd,(struct sockaddr*)&peeraddr,&peerlen))<)
        {
                printf("accept failed\n");
                exit();
        }
        printf("ip=%s, port=%d\n",inet_ntoa(peeraddr.sin_addr),ntohs(peeraddr.sin_port));

        pid_t pid;
        pid = fork();
        if (pid == -)
        {
                printf("server fork failed\n");
                exit();
        }

        if(pid == ) //send to client data
        {
                char recvbuf[];
                while ()
                {
                        memset(recvbuf, ,sizeof(recvbuf));
                        int ret = read(conn,recvbuf,sizeof(recvbuf));
                        if( ret == -)
                        {
                                printf("server read failed\n");
                                exit();
                        }
                        else if (ret == )
                        {
                                printf("client close\n");
                                break;
                        }
                        fputs(recvbuf,stdout);
                }
                printf("parent close \n");
                kill(pid,SIGUSR1);
                close(conn);
                exit();
        }
        else //recv from client data
        {
                signal(SIGUSR1,handler);
                char sendbuf[]={};
                while(fgets(sendbuf,sizeof(sendbuf),stdin) != NULL)
                {
                        write(conn,sendbuf,strlen(sendbuf));
                        memset(sendbuf,  ,sizeof(sendbuf));
                }
                printf("server childpid close\n");
                close(conn);
                exit();
        }
        close(listenfd);
        return ;
}

client

#include <stdio.h>
#include <sys/types.h>          /* See NOTES */
#include <sys/socket.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>

void handler(int sig)
{
        printf("recv a sig=%d\n",sig);
        exit();
}

int main(void)
{
        int sock;
        sock = socket(PF_INET,SOCK_STREAM,);
        if(sock < )
        {
                printf("creat socket failed\n");
                exit();
        }
        struct sockaddr_in servaddr;
        memset(&servaddr,,sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons();
        //servaddr.sin_addr.s_addr = htonl(INADDR_ANY);//host any address
        servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");

        if(connect(sock,(struct sockaddr*)&servaddr,sizeof(servaddr))<)
        {
                printf("connect failed \n");
                exit();
        }
        pid_t pid;
        pid=fork();
        if(pid == -)
        {
                printf("client fork failed\n");
                exit();
        }
        if(pid == ) // recv from server data
        {
                char recvbuf[] = {};
                while()
                {
                        memset(recvbuf,,sizeof(recvbuf));
                        int ret = read(sock,recvbuf,sizeof(recvbuf));
                        if(ret == -)
                        {
                                printf("read faileed\n");
                                exit();
                        }
                        else if(ret ==)
                        {
                                printf("server close\n");
                                break;
                        }
                        fputs(recvbuf,stdout);
                }
                close(sock);
                kill(getppid(),SIGUSR1);
        }
        else //send to server data
        {
                signal(SIGUSR1,handler);
                char sendbuf[] = {};
                while(fgets(sendbuf,sizeof(sendbuf),stdin) != NULL)
                {
                        write(sock, sendbuf,strlen(sendbuf));
                        memset(sendbuf,,sizeof(sendbuf));
                }
                close(sock);
        }
        return ;
}