socket 매핑 서버 - (다중 클라이언트 연결 처리 (fork), 종료 정보 표시)

#include 
#include           /* See NOTES */
#include 
#include 
#include 
#include in.h>
#include 
#include <string.h>
#include 

void do_service(int conn)
{
        char recvbuf[1024];
        while(1)
        {
                memset(recvbuf,0,sizeof(recvbuf));
                int ret = read(conn,recvbuf,sizeof(recvbuf));
                if(ret == 0)
                {
                        printf("client close
");
                        break;
                }
                else if (ret == -1)
                {
                        printf("read failed 
");
                        exit(1);
                }
                fputs(recvbuf,stdout);
                write(conn,recvbuf,ret);
        }
}

int main(void)
{
        int listenfd;
        listenfd = socket(PF_INET,SOCK_STREAM,0);
        if(listenfd < 0)
        {
                printf("creat socket failed
");
                exit(1);
        }
        struct sockaddr_in servaddr;
        memset(&servaddr,0,sizeof(servaddr));
        servaddr.sin_family = AF_INET;
        servaddr.sin_port = htons(5188);
        servaddr.sin_addr.s_addr = htonl(INADDR_ANY);//host any address

        int n=1;
        if(setsockopt(listenfd,SOL_SOCKET,SO_REUSEADDR,&n,sizeof(n))<0)
        {
                printf("set resueaddr failed
");
                exit(1);
        }

        if(bind(listenfd,(struct sockaddr*)&servaddr,sizeof(servaddr))<0)
        {
                printf("bind fialed
");
                exit(1);
        }
        if(listen(listenfd,SOMAXCONN)<0)
        {
                printf("listen failed
");
                exit(1);
        }
        struct sockaddr_in peeraddr;
        socklen_t peerlen = sizeof(peeraddr);
        int conn;
        pid_t pid;
        while(1)
        {
                if((conn=accept(listenfd,(struct sockaddr*)&peeraddr,&peerlen))<0)
                {
                        printf("accept failed
");
                        exit(1);
                }
                printf("ip=%s, port=%d
",inet_ntoa(peeraddr.sin_addr),ntohs(peeraddr.
sin_port));
                pid = fork();
                if(pid == -1)
                {
                        printf("fork failed
");
                        exit(1);
                }
                if (pid == 0)
                {
                        close(listenfd);
                        do_service(conn);
                        exit(1);
                }
                else
                {
                        close(conn);
                }
        }

        return 0;
}