HTTP and HTTPS

PHP 3, PHP 4. https:// since PHP 4.3.0

• http://example.com

• http://user:password@example.com

• https://example.com

• https://user:password@example.com

Allows read-only access to files/resources via HTTP 1.0, using the HTTP GET method. A Host: header is sent with the request to handle name-based virtual hosts. If you have configured a user_agent string using your ini file or the stream context, it will also be included in the request.

Redirects have been supported since PHP 4.0.5; if you are using an earlier version you will need to include trailing slashes in your URLs. If it's important to know the url of the resource where your document came from (after all redirects have been processed), you'll need to process the series of response headers returned by the stream.

<?php
$url = 'http://www.example.com/redirecting_page.php';

$fp = fopen($url, 'r');

/* Prior to PHP 4.3.0 use $http_response_header 
   instead of stream_get_meta_data() */
foreach(stream_get_meta_data($fp) as $response) {

  /* Were we redirected? */
  if (substr(strtolower($response), 0, 10) == 'location: ') {
    /* update $url with where we were redirected to */
    $url = substr($response, 10);
  }

}

?>

The stream allows access to the body of the resource; the headers are stored in the $http_response_header variable. Since PHP 4.3.0, the headers are available using stream_get_meta_data().

HTTP connections are read-only; you cannot write data or copy files to an HTTP resource.