Linux Tcp通信——服务器与客户端

#include 

#include 




#include 

#include 

#include 

#include 

#include 

#include 

#include 







#define SERVERPORT 8000

#define MAXLIN 4096




int main(void)

{

  int sockServer = -1;

  int connfd = -1;

  struct sockaddr_in addrClient; //client addr




    //01 create socket

    sockServer = socket(AF_INET, SOCK_STREAM, 0);

    //check is success

    if (sockServer < 0)

    {

      printf("create socket server faild!\n");

        return -1;

    }

    else

    {

        printf("create socket server success!\n");

    }




    //02 init server, fullfill sockaddr_in

    struct sockaddr_in addr;

    bzero(&addr, sizeof(addr));

    addr.sin_family = AF_INET;

    addr.sin_port = htons(SERVERPORT);

    addr.sin_addr.s_addr = htonl(INADDR_ANY) ;// receive data from any ip




  //设置该端口可复用

  socklen_t buflen = 1;

  socklen_t len = sizeof(buflen);

  setsockopt(sockServer, SOL_SOCKET, SO_REUSEADDR, &buflen,len);




    //03 bind socket

    int err = bind(sockServer, (struct sockaddr *)&addr, sizeof(addr));




    if (err < 0)

    {

        printf("bind() called failed!\n");

        return -1;

    }

    else

    {

        printf("bind() called success! \n");

    }




    //04 set the socket to listen mode, ready to receive client requests

    if(listen(sockServer, 5) < 0)

    {

        printf("listen() called failed!\n");

        return -1;

    }

    else

    {

        printf("listen() called successful!\n");

    }




    socklen_t sin_size = sizeof(struct sockaddr_in);




    const int nTempLen = 4096;

    char *recvbuf = (char *)malloc((size_t)nTempLen);




    while(1)

    {

      printf("wait client connecting ......\n");

      connfd = accept(sockServer,

                        (struct sockaddr *)&(addrClient),

                        &sin_size);

printf(" client connect success !!! ip is: %s \n",(inet_ntoa)(addrClient.sin_addr));




        while(connfd)   //modify  TcpServerRecv

        {

            //取实际收到的数据长度

            int nRecv = recv(connfd, recvbuf, nTempLen, 0);

            printf("recv size is %d \n",nRecv);




            if(nRecv <=0 && errno != EINTR)

            {

                printf(" client disconnect !\n" );

                break;

            }




            if(nRecv > 1)

            {

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




                if(send(connfd,recvbuf,nTempLen,0)<0)

                {

                   printf("send msg error :%s(errno:%d)\n",strerror(errno),errno);

                }

            }




            memset(recvbuf, 0, strlen(recvbuf));




        }




    }




  puts("!!!Hello World!!!"); /* prints !!!Hello World!!! */

  return EXIT_SUCCESS;

}