嵌入式 setsockopt设置socket—attr达到send立即发送不延时MTU

void start_jrm(void)
{
 FILE *fp;
 char buf[4096];
 unsigned int myport;
 int on = 1;
 int sockfd,new_fd,len;
 SOCK_ATTR sock_attr;
 struct sockaddr_in my_addr, their_addr;
       char certificate[128] = "cacert.pem";
       char privatekey[128] = "privkey.pem"; 

 fp = fopen(config_file, "r");
 while(fgets(buf, sizeof(buf), fp)){

  if(strstr(buf,"listen_port")){
   myport = atoi(buf+sizeof("listen_port"));
  }
 }
   fclose(fp);
 eric_print("bind port %d\n",myport);

 //start_config_warden();
 if ((sockfd = socket(PF_INET, SOCK_STREAM, IPPROTO_IP)) == -1) { 
  perror("socket");
  exit(1);
 } else
 eric_print("socket created\n");

 bzero(&my_addr, sizeof(my_addr));
 my_addr.sin_family = PF_INET;
 my_addr.sin_port = htons(myport);//big or small endian problems

 my_addr.sin_addr.s_addr = 0;//why????
 setsockopt (sockfd, SOL_SOCKET,SO_REUSEADDR,TCP_NODELAY, (void *) &on, sizeof (on)); //Solve the port takes up
 if (bind(sockfd, (struct sockaddr *) &my_addr, sizeof(struct sockaddr)) == -1) {
  perror("bind");
  exit(1);
 } else
 eric_print("binded\n");

 if (listen(sockfd, 5) == -1) {
  perror("listen");
  exit(1);
 } else{
  eric_print("begin listen port %d\n",myport);
 }
 sock_attr.ctx =init_ssl(0);
 sec_load_cert_file(sock_attr.ctx,certificate,privatekey);//install certificate in server
 
 while(1){
         len = sizeof(struct sockaddr);
   //in the listening state
         if ((new_fd = accept(sockfd, (struct sockaddr *) &their_addr,&len)) == -1) {
             perror("accept");
             eric_print("accept error! \n");
         } else{
             eric_print("tcp server: got connection from %s, port %d, socket %d\n",
                    inet_ntoa(their_addr.sin_addr),
                    ntohs(their_addr.sin_port), new_fd);
         }
  sock_attr.sockfd = new_fd;
  handle_connection(sock_attr);//to oprate the new sock every time, then continue listening ???
  
 }

}