$options = array(
  'http'=>array(
    'method'=>"POST",
    'header'=>
      "Accept-language: en\r\n".
      "Content-type: application/x-www-form-urlencoded\r\n",
    'content'=>http_build_query(array('foo'=>'bar'))
));

$context = stream_context_create($options);

fopen('http://www.example.com/',false,$context);