Network client/server (二)

#include <sys/types.h>
#include <sys/socket.h>
#include <stdio.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>

int main()
{
  int server_sockfd, client_sockfd;
  int server_len, client_len;

  struct  sockaddr_in  server_address;
  struct  sockaddr_in  client_address;
  unlink("server_socket");
  
  server_sockfd = socket(AF_INET, SOCK_STREAM, 0);
  server_address.sin_family = AF_INET;
  server_address.sin_addr.s_addr = htonl(INADDR_ANY);
  server_address.sin_port = htons(9734);
  server_len = sizeof(server_address);

bind(server_sockfd, (struct sockaddr*)&server_address, server_len);
listen(server_sockfd, 5);

  while(1)
  {
    char ch;
    printf("server waiting\n");
    client_len = sizeof(client_address);
    client_sockfd = accept(server_sockfd, (struct sockaddr*)&client_address, &client_len);
  
    read(client_sockfd, &ch, 1);
    ch++;
    write(client_sockfd, &ch,1);

    close(client_sockfd);
  } 
}