multclient.c

    #include"stdio.h"    
    #include"stdlib.h"    
    #include"sys/types.h"    
    #include"sys/socket.h"    
    #include"string.h"    
    #include"netinet/in.h"    
    #include"netdb.h"  
        
    #define PORT 4444   
    #define BUF_SIZE 2000   
        
    int main(int argc, char**argv) {    
     struct sockaddr_in addr, cl_addr;    
     int sockfd, ret;    
     char buffer[BUF_SIZE];    
     struct hostent * server;  
     char * serverAddr;  
      
     if (argc < 2) {  
      printf("usage: client < ip address >\n");  
      exit(1);    
     }  
      
     serverAddr = argv[1];   
       
     sockfd = socket(AF_INET, SOCK_STREAM, 0);    
     if (sockfd < 0) {    
      printf("Error creating socket!\n");    
      exit(1);    
     }    
     printf("Socket created...\n");     
      
     memset(&addr, 0, sizeof(addr));    
     addr.sin_family = AF_INET;    
     addr.sin_addr.s_addr = inet_addr(serverAddr);  
     addr.sin_port = PORT;       
      
     ret = connect(sockfd, (struct sockaddr *) &addr, sizeof(addr));    
     if (ret < 0) {    
      printf("Error connecting to the server!\n");    
      exit(1);    
     }    
     printf("Connected to the server...\n");    
      
     memset(buffer, 0, BUF_SIZE);  
     printf("Enter your message(s): ");  
      
     while (fgets(buffer, BUF_SIZE, stdin) != NULL) {  
      ret = sendto(sockfd, buffer, BUF_SIZE, 0, (struct sockaddr *) &addr, sizeof(addr));    
      if (ret < 0) {    
       printf("Error sending data!\n\t-%s", buffer);    
      }  
      ret = recvfrom(sockfd, buffer, BUF_SIZE, 0, NULL, NULL);    
      if (ret < 0) {    
       printf("Error receiving data!\n");      
      } else {  
       printf("Received: ");  
       fputs(buffer, stdout);  
       printf("\n");  
      }    
     }  
       
     return 0;      
    }