How can be stored an array of sockets?

Hello all,

I have in mind the creation of a chat server to test how do the sockets work.

I created a simple server which attends 1 client at a time and then closes the connection.

Now I would need to know how to store that client sockets into an array so I can later make them to communicate between them using the file descriptor creating a child process for each one.

I got this code so far:

Code:

// Standard libs
#include <stdio.h>

// Socket related libs
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>

#define PORT 4000
#define CLIENTS 2

int main(void)
{
    // File descriptors for client and server
    int socketServer;
    int socketClient;
    
    struct sockaddr_in server;
    struct sockaddr_in client;
    
    int sin_size;

    print_info();

    printf("Initializing server...\n");
    
    printf("Creating sockets... ");
    if((socketServer=socket(AF_INET, SOCK_STREAM, 0)) == -1){
        printf("[FAILED]\n");
        perror("Initializing socket()");
        return 1;
    }
    else printf("[OK]\n");
    
    server.sin_family = AF_INET;
    
    server.sin_port = htons(PORT);
    server.sin_addr.s_addr = INADDR_ANY;
    bzero(&(server.sin_zero),8);
    
    printf("Binding sockets... ");
    if(bind(socketServer,(struct sockaddr*)&server,
           sizeof(struct sockaddr))==-1) {
                   printf("[FAILED]\n");
                   perror("bind()");
                  return 1;
      }
      else printf("[OK]\n");
      
      printf("Listening on port %d... ",PORT);
      if(listen(socketServer,CLIENTS) == -1) {
          printf("[FAILED]\n");
          perror("listen()");
          return 1;
      }
      else printf("[OK]\n");
      
      // Continuously accepting remote connections
      while(1){
          sin_size=sizeof(struct sockaddr_in);
          
          if ((socketClient = accept(socketServer,(struct sockaddr *)&client,
                        &sin_size))==-1) {
                            perror("accept()");
                            return 1;
        }
        
        printf("Connection accepted from %s\n",
                    inet_ntoa(client.sin_addr)
        );
        
        printf("Sending welcome message...\n");
        send(socketClient,"Welcome to my server\n",22,0);
        
        printf("Closing client connection\n");
        close(socketClient);
      }
    
    close(socketServer);
    return 0;
}

I would appreciate any help about how to do it.

Regards,

Ernie-

Code:

SOCKET sockets[CLIENTS] = (SOCKET*)malloc(sizeof(SOCKET) * CLIENTS)

?

Sorry. I don't know C very well. Although so far, whenever I put SOCKETs into an array or try to use them in a function, they seem to always produce errors. I don't know how that works considering its just a u_int but...

You took the two different solutions and combined them into one (that doesn't work.)

Use EITHER:

Code:

SOCKET sockets[CLIENTS]; /* no malloc, stack memory */

OR:

Code:

SOCKET *sockets = malloc(sizeof(SOCKET) * CLIENTS); /* heap memory, so it's a pointer, no array */

Also note that typecasting malloc is bad > FAQ > Casting malloc - Cprogramming.com

Originally Posted by memcpy

You took the two different solutions and combined them into one (that doesn't work.)

Use EITHER:

Code:

SOCKET sockets[CLIENTS]; /* no malloc, stack memory */

OR:

Code:

SOCKET *sockets = malloc(sizeof(SOCKET) * CLIENTS); /* heap memory, so it's a pointer, no array */

Also note that typecasting malloc is bad > FAQ > Casting malloc - Cprogramming.com

Thanks for the info. C confuses me at times o.e

Originally Posted by Rodaxoleaux

Thanks for the info. C confuses me at times o.e

Yeah, the compiler does crazy tish like warning you of "incompatible types in assignment". WTF is that?

Originally Posted by Ernie-

how to store that client sockets into an array

In C, sockets are identified with file descriptors, which are ints. You know how to create an array of ints, right?