client.c

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

#define BUFFER_SIZE 1024

int main(int argc, char *argv[])
{
    if (argc != 3)
    {
        fprintf(stderr, "Usage: %s <server_ip> <port>\n", argv[0]);
        exit(EXIT_FAILURE);
    }

    char *server_ip = argv[1];
    int port = atoi(argv[2]);

    int sockfd;
    struct sockaddr_in servaddr;
    char buffer[BUFFER_SIZE];

    // Create socket
    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd < 0)
    {
        perror("Socket creation failed");
        exit(EXIT_FAILURE);
    }

    // Prepare the server address
    servaddr.sin_family = AF_INET;
    servaddr.sin_port = htons(port);
    servaddr.sin_addr.s_addr = inet_addr(server_ip);

    // Connect to server
    if (connect(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) < 0)
    {
        perror("Connection failed");
        exit(EXIT_FAILURE);
    }

    printf("Connected to server\n");

    // Prompt user for roll number
    printf("Enter roll number: ");
    fgets(buffer, BUFFER_SIZE, stdin);
    strtok(buffer, "\n"); // Remove trailing newline if present

    // Send roll number to server
    send(sockfd, buffer, strlen(buffer), 0);

    // receive attendace status from server if attendance is marked then print "Attendance Marked" else print "Attendance not marked"
    recv(sockfd, buffer, BUFFER_SIZE, 0);
    printf("%s\n", buffer);

    // Close connection
    close(sockfd);

    return 0;
}