Valhalla Legends Archive

'm doing a simple program in socket programming on c i have server that can handle 2clients in a single machine i'm running ubuntu linux so i got it work but the probelm when clients send a message the server will echo it but i cant distinguish which client send the message client 1 or client 2 here is the code for the server whenever a client sent a message it will be shown in the server side as( client sent : hi)i cant know which client sent it please help

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <arpa/inet.h>
#include <sys/types.h>
#include <sys/socket.h>

#define BUFFER_SIZE  1024

int serverfd;
int clientfd;

int n;
int addrSize;
int serverPort;
char clientIP[25];
char buffer[BUFFER_SIZE];
struct sockaddr_in serverAddr;
struct sockaddr_in clientAddr;

int main(int argc, char* argv[])
{
   if(argc < 2)
   {
      printf("Usage: ./server <port>\n");
      exit(0);
   }
   else
   {
      serverPort = atoi(argv[1]);
   }

   addrSize = sizeof(struct sockaddr);

   /* Create a TCP socket */
   serverfd = socket(AF_INET, SOCK_STREAM, 0);

   if(serverfd < 0)
      printf("Error creating server socket");
   serverAddr.sin_family = AF_INET;
   serverAddr.sin_port = htons(serverPort); /* Specify a port */
   serverAddr.sin_addr.s_addr = INADDR_ANY; /* Accept connections from anywhere */
   memset(&(serverAddr.sin_zero), '\0', ; /* This must be set to zero */

   /* Bind our server socket */
   if(bind(serverfd, (struct sockaddr*)&serverAddr, sizeof(struct sockaddr)) == -1)
      printf("Could not bind()\n");

   /* Start listening on socket for incoming connections */
   if(listen(serverfd, 10) == -1)
      printf("Could not listen()\n");
   fork();//this is the magical line...
   /* accept() accepts an incoming connection and fills a sockaddr_in structure with client information */
   clientfd = accept(serverfd, (struct sockaddr*)&clientAddr, &addrSize);
   
   /* inet_ntoa() converts an IP address to a displayable string */
   snprintf(clientIP, sizeof(clientIP), "%s", inet_ntoa(clientAddr.sin_addr));
   printf("Got connection from %s\n", clientIP);

   do
   {
      n = recv(clientfd, buffer, BUFFER_SIZE, 0); /* Receive message from client */
      buffer[n] = '\0'; /* terminate string */

      send(clientfd, buffer, BUFFER_SIZE, 0); /* Echo message back to client */
      printf("Client sent: %s\n" , buffer);
   }
   while(strncmp(buffer, "exit", 4) != 0); /* Exit when client sends "exit" */

   close(serverfd); /* Close socket */
   
   return 0;
}




#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include
<arpa/inet.h>
#include
<sys/types.h>
#include
<sys/socket.h>

#define
BUFFER_SIZE 1024

int sockfd;

int n;
int addrSize;
int serverPort;
char serverIP[25];
char
buffer[BUFFER_SIZE];
struct sockaddr_in serverAddr;

int main(int argc,
char* argv[])
{
if(argc < 3)
{
printf("Usage: ./client <server ip>
<server port>\n");
exit(0);
}
else
{
snprintf(serverIP, sizeof(serverIP),
"%s", argv[1]);
serverPort = atoi(argv[2]);
}

addrSize = sizeof(struct sockaddr);

/* Create a TCP socket */
sockfd = socket(AF_INET, SOCK_STREAM, 0);

if(sockfd < 0)
printf("Error creating socket");

serverAddr.sin_family = AF_INET;
serverAddr.sin_port = htons(serverPort); /* Server port */
inet_pton(AF_INET, serverIP, &serverAddr.sin_addr); /*
Server IP Address */
memset(&(serverAddr.sin_zero), '\0', ; /* This must
be set to zero */

/* Connect to server */
if(connect(sockfd, (struct sockaddr*)&serverAddr,
addrSize) != 0)
{
printf("Error: Could not connect to %s on
port %d\n", serverIP, serverPort);
exit(0);
}
else
printf("Connected to %s on port %d\n\n",
serverIP, serverPort);

do
{
printf("> ");
fgets(buffer, BUFFER_SIZE, stdin);
send(sockfd, buffer, strlen(buffer), 0); /* Send
message to server */

n = recv(sockfd, buffer, BUFFER_SIZE, 0); /*
Receive message from server */
buffer[n] = '\0'; /* terminate string */
printf("< %s\n", buffer);
}
while(strncmp(buffer, "exit", 4) != 0); /* Exit
when message is "exit" */

close(sockfd); /* Close socket */

return 0;
}

how toi Create for example 2 files, namely: server, client,
Server: act as servers/provider, will receive all requests from different client
Client: requesters meaning that server handle multiple client can i?i'm new to socket progarmming