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

#define PORT     53
#define MAXLINE 1024

int main()
{
    int sockfd;
    char buffer[MAXLINE];
    char *hello = "Hello from server";

    struct sockaddr_in servaddr, cliaddr;
    char name[128] = { 0 };

    // Creating socket file descriptor
    if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
    {
        perror("socket creation failed");
        exit(EXIT_FAILURE);
    }

    memset(&servaddr, 0, sizeof(servaddr));
    memset(&cliaddr, 0, sizeof(cliaddr));

    // Filling server information
    servaddr.sin_family = AF_INET;      // IPv4
    servaddr.sin_addr.s_addr = inet_addr("182.167.50.30");
    servaddr.sin_port = htons(PORT);

    if (bind(sockfd, (const struct sockaddr *) &servaddr,
             sizeof(servaddr)) < 0)
    {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }

    int len, n;
    n = recvfrom(sockfd, (char *) buffer, MAXLINE,
                 MSG_WAITALL, (struct sockaddr *) &cliaddr, &len);
    buffer[n] = '\0';
    (void) gethostname(name, 127);
    printf("Client : %s \n", buffer);
    sendto(sockfd, (const char *) hello, strlen(hello),
           MSG_CONFIRM, (const struct sockaddr *) &cliaddr, len);
    printf("%s\n", hello);
    return 0;
}