- how do i know if an email has been delivered using PHP?
- header('Content-Type: image/png');
- $im = @imagecreate(1, 1);
- $background_color = imagecolorallocate($im, 255, 255, 255); // make it white
- imagepng($im,"image.png");
- imagedestroy($im);
- $id = sha1([ID FROM DATABASE] + salt)
- <img src="http://www.example.com/image.php?id=SHA1HASHHERE" />