How to simulate a mouse movement

Here's some modified Win32 code I had lying around:

#define WIN32_LEAN_AND_MEAN
#define _WIN32_WINNT 0x0500

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


#define X 123
#define Y 123
#define SCREEN_WIDTH 1024
#define SCREEN_HEIGHT 800


void MouseSetup(INPUT *buffer)
{
    buffer->type = INPUT_MOUSE;
    buffer->mi.dx = (0 * (0xFFFF / SCREEN_WIDTH));
    buffer->mi.dy = (0 * (0xFFFF / SCREEN_HEIGHT));
    buffer->mi.mouseData = 0;
    buffer->mi.dwFlags = MOUSEEVENTF_ABSOLUTE;
    buffer->mi.time = 0;
    buffer->mi.dwExtraInfo = 0;
}


void MouseMoveAbsolute(INPUT *buffer, int x, int y)
{
    buffer->mi.dx = (x * (0xFFFF / SCREEN_WIDTH));
    buffer->mi.dy = (y * (0xFFFF / SCREEN_HEIGHT));
    buffer->mi.dwFlags = (MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_MOVE);

    SendInput(1, buffer, sizeof(INPUT));
}


void MouseClick(INPUT *buffer)
{
    buffer->mi.dwFlags = (MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_LEFTDOWN);
    SendInput(1, buffer, sizeof(INPUT));

    Sleep(10);

    buffer->mi.dwFlags = (MOUSEEVENTF_ABSOLUTE | MOUSEEVENTF_LEFTUP);
    SendInput(1, buffer, sizeof(INPUT));
}


int main(int argc, char *argv[])
{
    INPUT buffer[1];

    MouseSetup(&buffer);

    MouseMoveAbsolute(&buffer, X, Y);
    MouseClick(&buffer);

    return 0;
}

You'll need to call MouseSetup() to each INPUT buffer before you use it.

Resources

MSDN - SendInput()
MSDN - INPUT
MSDN - MOUSEINPUT

Here is a solution using Xlib for those who use Linux :

#include <X11/Xlib.h>
#include<stdio.h>
#include<unistd.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>

void mouseClick(int button)
{
    Display *display = XOpenDisplay(NULL);

    XEvent event;

    if(display == NULL)
    {
        fprintf(stderr, "Errore nell'apertura del Display !!!\n");
        exit(EXIT_FAILURE);
    }

    memset(&event, 0x00, sizeof(event));

    event.type = ButtonPress;
    event.xbutton.button = button;
    event.xbutton.same_screen = True;

    XQueryPointer(display, RootWindow(display, DefaultScreen(display)), &event.xbutton.root, &event.xbutton.window, &event.xbutton.x_root, &event.xbutton.y_root, &event.xbutton.x, &event.xbutton.y, &event.xbutton.state);

    event.xbutton.subwindow = event.xbutton.window;

    while(event.xbutton.subwindow)
    {
        event.xbutton.window = event.xbutton.subwindow;

        XQueryPointer(display, event.xbutton.window, &event.xbutton.root, &event.xbutton.subwindow, &event.xbutton.x_root, &event.xbutton.y_root, &event.xbutton.x, &event.xbutton.y, &event.xbutton.state);
    }

    if(XSendEvent(display, PointerWindow, True, 0xfff, &event) == 0) fprintf(stderr, "Error\n");

    XFlush(display);

    usleep(100000);

    event.type = ButtonRelease;
    event.xbutton.state = 0x100;

    if(XSendEvent(display, PointerWindow, True, 0xfff, &event) == 0) fprintf(stderr, "Error\n");

    XFlush(display);

    XCloseDisplay(display);
}


int main(int argc, char * argv[]) {

    int x , y;
    x = atoi(argv[1]);
    y = atoi(argv[2]);
    Display *display = XOpenDisplay(0);

    Window root = DefaultRootWindow(display);
    XWarpPointer(display, None, root, 0, 0, 0, 0, x, y);
    mouseClick(Button1);
    XFlush(display);
    XCloseDisplay(display);
    return 0;
}

Just Build it and then to simulate a click at x ,y do:

$ ./a.out x y

i.e.

$g++ -lX11 sgmousesim2.cpp

$./a.out 123 13