如何从服务器中的某些数据写入连接到服务器的所有客户端？

Question

我有一个小问题，但找不到任何解决方案。我有此代码。

服务器代码

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>
#include <pthread.h>

#define PORT 2908
extern int errno;

typedef struct thData{
    int idThread; 
    int cl; 
}thData;

static void *treat(void *); 
void raspunde(void *);

int main ()
{
  struct sockaddr_in server;    
  struct sockaddr_in from;  
  int nr;       
  int sd;       
  int pid;
  pthread_t th[100];
    int i=0;



  if ((sd = socket (AF_INET, SOCK_STREAM, 0)) == -1)
    {

      return errno;
    }
  int on=1;
  setsockopt(sd,SOL_SOCKET,SO_REUSEADDR,&on,sizeof(on));

  bzero (&server, sizeof (server));
  bzero (&from, sizeof (from));

    server.sin_family = AF_INET;    
    server.sin_addr.s_addr = htonl (INADDR_ANY);
    server.sin_port = htons (PORT);

  /
  if (bind (sd, (struct sockaddr *) &server, sizeof (struct sockaddr)) == -1)
    {

      return errno;
    }


  if (listen (sd, 2) == -1)
    {
      perror ("[server]Error at listen().
");
      return errno;
    }

  while (1)
    {
      int client;
      thData * td;     
      int length = sizeof (from);


      fflush (stdout);


      if ( (client = accept (sd, (struct sockaddr *) &from, &length)) < 0)
    {
      perror ("[server]Error at accept().
");
      continue;
    }

    td=(struct thData*)malloc(sizeof(struct thData));   
    td->idThread=i++;
    td->cl=client;

    pthread_create(&th[i], NULL, &treat, td);         

    }//while    
};              
static void *treat(void * arg)
{       
        struct thData tdL; 
        tdL= *((struct thData*)arg);    
        printf ("[thread]- %d - Waiting the message...
", tdL.idThread);
        fflush (stdout);         
        pthread_detach(pthread_self());     
        raspunde((struct thData*)arg);
        close ((intptr_t)arg);
        return(NULL);   

};


void raspunde(void *arg)
{
        int nr, i=0;
    struct thData tdL; 
    tdL= *((struct thData*)arg);
    if (read (tdL.cl, &nr,sizeof(int)) <= 0)
            {
              printf("[Thread %d]
",tdL.idThread);
              perror ("Error at read() from client.
");

            }

    printf ("[Thread %d]The message is...%d
",tdL.idThread, nr);


              nr++;      
    printf("[Thread %d]Sending the message back...%d
",tdL.idThread, nr);

        printf("%d
",tdL.cl );
     if (write (tdL.cl, &nr, sizeof(int)) <= 0)
        {
         printf("[Thread %d] ",tdL.idThread);
         perror ("[Thread]Error at write() from client.
");
        }
    else
        printf ("[Thread %d]The message was sent.
",tdL.idThread); 

}

上面的代码是一个为每个客户端创建线程的服务器。客户端向服务器发送一个号码，服务器将以数字加1的方式回复给客户端。

问题是，如何将响应函数中的nr或字符串消息写至服务器上连接的所有客户端？

谢谢您！

我有一个小问题，但找不到任何解决方案。我有这个代码。服务器代码#include #include #include #include ...