Agfdhyk

What if I had a an array of struct. Is it possible for me to send an array of structs over a socket? The struct size will be updated continuously and at any time I would be able to print out the content of the structs. I hope this makes sense, my explanation might not be cleared. My syntax is definitely not correct for some areas, it's just a snippet of what I think it would look like. I just need some guidance.

This will send the array of structs acorss the socket.

void sendOpenMessage(int num0, int num1, int num2){



  struct openMessage{

     int num0;

     int num1;

     int num2



  };

  struct openMessage open[100];

  int i = 0;

  open[i].num0 = 1;

  open[i].num1 = 2;

  open[i].num2 = 3;  



  int length = sizeof(open);

  if(send(socket, &open[i], length, 0) == -1){

       fprintf(stderr, "Send() failed");

  }else{

      printf("Open message is being sentn");

  }

  i++;

} 

This will receive the struct and display the contents in a message

  struct openMessage open[100];

  if(recv(clnSocket, &open, sizeof(open), 0) < 0){

      fprintf(stderr,"Recv() failedn");

      printf("Error code: %dn", errno);

  }



  //Get size of the current struct 

  //Print out the messages from the structs that have messages?

  void printStruct(struct openMessage open){

     for(int i = 0; i < sizeof(the struct); i++){

           printf("%dn",open[i].num0);

           printf("%dn", open[i].num1);

           printf("%dn", open[i].num2);

     }

  }

First of all, you need to read up about byte ordering and serialisation.

Secondly, length is the size of the whole array, so when i is zero you send the whole array, when i is 1 you send all but the first element plus some garbage at the end, and so on.
Thirdly, when receiving you iterate across sizeof(the struct) members of the array. Don't you want to iterate across the whole array?

When you say the struct size will be updated continuously, do you mean the number of elements in the array? Your struct has a fixed size.

If you are sending variable quantities of data, i.e. if you want to send a piece of data that has one length at one time and another length at another time, or even if you want the number of elements in the array to update dynamically, then you MUST send that size across the socket, and send it before the data. Send the size first, read it first on the receiving end, and then the receiving end will know how much more data to read, and more importantly, where the data ends so that if there is more data later it doesn't all get mixed up.