TCP Client-Server Program to Check Palindrome String

A Palindrome is a word, phrase, or sequence that reads the same backward as forward, e.g., "madam" or "nurses run".

TCP Client-Server Program

Client and server configuration in which a client connects transmits a string to the server, and the server displays the original string and sends a confirmation to the client through socket connection whether the string is a palindrome or not.

Input − WOW

Output − Palindrome

Input − soap

Output − Not Palindrome

How Does It Work?

• First, establish a client-server connection.

• After the connection is established, the client utilizes the send system function to deliver the user input string to the server.

• The server will wait for a string supplied by the client on the client-side.

• The reading system call is used by the server to read the string.

• After that, the server determines whether or not the string is a palindrome and returns the confirmation to the client.

Compiling

• Run the server application as a GCC server first.

server./server c –o

• Run the GCC client program on a different terminal.

client./client c -o

• The client's string is being awaited by the server software.

• Client-side, enter the string.

• The original string will be printed by the server software.

• The result will be printed by the client software.

TCP Server

#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
main(){
   struct sockaddr_in client, server;
   int s1, n, sock, g, j, left, right, flag;
   char b11[20], b2[10], b3[10], b4[10];

   s1 = socket(AF_INET, SOCK_STREAM, 0);
   server.sin_family = AF_INET;
   server.sin_port = 20000;
   server.sin_addr.s_addr = inet_addr("127.0.0.1");
   bind(s1, (struct sockaddr*)&server, sizeof server);
   listen(s1, 1);
   n = sizeof client;
   sock = accept(s1, (struct sockaddr*)&client, &n);
   for (;;) {
      recv(sock, b11, sizeof(b1), 0);

      printf("The string received is:%s", b11);
      if (strlen(b11) == 0)
         flag = 1;
      else {
         left = 0;
         right = strlen(b11) - 1;
         flag = 1;
         while (left < right && flag) {
            if (b11[left] != b11[right])
               flag = 0;
               else {
                  left++;
                  right--;
            }
         }
      }
      send(sock, &flag, sizeof(int), 0);
      break;
   }
   close(sock);
   close(s1);
}

Client

#include <arpa/inet.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
main(){
   struct sockaddr_in client;
   int s, flag;
   char buffer[20];
   s = socket(AF_NET, SOCK_STREAM, 0);
   client.sin_family = AF_NET;
   client.sin_port = 20000;
   client.sin_addr.s_addr = inet_addr("127.0.0.1");
   connect(s, (struct sockaddr*)&client, sizeof client);
   for (;;) {
      printf("Enter a string to check palindrome: ");
      scanf("%s", buffer);

      printf("Client: %s", buffer);
      send(s, buffer, sizeof(buffer), 0);
      recv(s, &flag, sizeof(int), 0);

      if (flag == 1) {
         printf("Server: The string is Palindrome.");
         break;
      }
      else {
         printf("Server: The string isn't a palindrome.");
         break;
      }
   }
   close(s);
}