$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'http://www.facebook.com/login');
curl_setopt($ch, CURLOPT_USERAGENT,'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Ubuntu Chromium/32.0.1700.107 Chrome/32.0.1700.107 Safari/537.36');
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, "email=XXXXX&password=XXXXX"); // NO SE EXACTAMENTE QUE PARAMETROS RECIBE FACEBOOK EN EL FORM
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_COOKIESESSION, true);
$response = curl_exec($ch);
if (curl_error($ch)) {
echo curl_error($ch);
}
curl_setopt($ch, CURLOPT_URL, 'http://www.facebook.com/usuario');
curl_setopt($ch, CURLOPT_POST, false);
curl_setopt($ch, CURLOPT_POSTFIELDS, "");
$answer = curl_exec($ch);
if (curl_error($ch)) {
echo curl_error($ch);
}