Client and Server Programming In C

[Bhardwaj]

Hello, I am a student of BSC.I.T. and while learning the C language I want to know the Client and Server Programming in C language. But, as it is not in our syllabus I am not able to get it. So, if anyone is having details about it, then please provide me that. If you are having some or the other code then that will help me more. So, please reply me with some useful details about the Client and Server Programming In C. Is there any book available on this?

[opaper]

Client and server programming mostly done for the File transfer through Socket. For that you can make use of C. The user selected the file server that the client can download, the server accepts the connection, sends data and closes the connection. The client connects via the server's IP address [name resolution domain has come], download the file and closes the connection.

[Modifier]

Client and Server Programming In C is based on the Network programming which is based on sockets. The sockets are a standard mode of communication on the network, developed at Berkeley, which allow an application to interact with a protocol. It can be done on the same machine or on a remote machine via a network.
There are two modes of communications for LGA:

• the connected mode, which uses TCP
• disconnected mode, based on UDP

[Praetor]

I am not having more knowledge about the C language. But, I have one program on this which can help you a lot for getting information about it.
Client side program:

#ifdef code
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
int main(int argument, char *args[])
{
   printf("Client Side programming");
   int sock;
   int size;
   struct Address address;
   int answer;
   char ch = 'A';
   sock = socket(AF_INET, SOCK_STREAM, 0);
   address.sin_family = AF_INET;
   address.sin_addr.s_addr = inet_addr("127.0.0.1");
   address.sin_port = htons(7734);
   size = sizeof(address);
   answer = connect(sock, (struct sockaddr *)&address, size);
   if(answer == 1)
   {
      perror("Error has occurred");
      exit(0);
   }
   write(sock, &ch, 1);
   read(sock, &ch, 1);
   printf("Char from server = %c\n", ch);
   close(sock);
   exit(0);
}

Server Side Program:

#ifdef code
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <unistd.h>
int main(int argument, char *args[])
{
   int server, client;
   int server_size, client_size;
   struct socaddress server_address;
   struct socaddress client_address;
   server = socket(AF_INET, SOCK_STREAM, 0);
   server_address.sin_family = AF_INET;
   server_address.sin_addr.s_addr = htons(INADDR_ANY);
   server_size = sizeof(server_address);
   bind(server, (struct sockaddr *) &server_address, server_size);
   listen(server, 5);
   while(1)
   {
      char ch;
      printf("server waiting\n");
      client_size = sizeof(client_address);
      client = accept(server, (struct sockaddr *) &client_address, &client_size);
      read(client, &ch, 1);
      ch++;
      write(client, &ch, 1);
      close(client);
   }
   return 0;
}

[MindSpace]

With sockets C you will be able to exchange blocks of data (or messages) between clients and servers. It will take "over" define and code a protocol that allows entities to act on the content of these messages. RMI stands for "Remote Method Invocation". Briefly, this is already a protocol and it allows you to operate the methods of a remote object. This is not quite the same level of abstraction. After all depends on what you want to do and what will enable you to achieve more easily.

[Modifier]

You can refer one of the following book for getting more knowledge:

• Object-Orientated Programming with ANSI-C
• C - Committee Draft of ISO9899:TC2
• C - The ISO Standard - Rationale
• C - Elements of Style
• Numerical Recipes in C - The Art of Scientific Computing
• The C Book
• Writing Bug Free C Code