client.c

/*
 * Client for Bank Management System
 * Author: Piyush Singh
 */

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

int main() {
    int sock = socket(AF_INET, SOCK_STREAM, 0);

    struct sockaddr_in addr = {0};
    addr.sin_family = AF_INET;
    addr.sin_port = htons(PORT);
    inet_pton(AF_INET, "127.0.0.1", &addr.sin_addr);

    if (connect(sock, (struct sockaddr*)&addr, sizeof(addr)) < 0) {
        printf("Connection failed\n");
        return 1;
    }

    printf("Connected to server\n\n");
    setvbuf(stdout, NULL, _IONBF, 0);

    char buffer[BUFFER_SIZE];
    char input[BUFFER_SIZE];
    struct pollfd fds[2];

    fds[0].fd = sock;
    fds[0].events = POLLIN;
    fds[1].fd = STDIN_FILENO;
    fds[1].events = POLLIN;

    while (1) {
        if (poll(fds, 2, 100) > 0) {
            if (fds[0].revents & POLLIN) {
                memset(buffer, 0, BUFFER_SIZE);
                int n = read(sock, buffer, BUFFER_SIZE - 1);
                if (n <= 0) break;
                printf("%s", buffer);
            }

            if (fds[1].revents & POLLIN) {
                if (!fgets(input, BUFFER_SIZE, stdin)) break;
                input[strcspn(input, "\n")] = 0;
                if (write(sock, input, strlen(input)) <= 0) break;
            }
        }
    }

    close(sock);
    printf("\nDisconnected\n");
    return 0;
}