List of Supported Protocols/Wrappers
PHP Manual

HTTP and HTTPS

PHP 4, PHP 5. https:// since PHP 4.3.0

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 php.ini file or the stream context, it will also be included in the request.

Aviso

Quando usando SSL, o Microsoft IIS irá violar o protocolo fechando a conexão sem enviar uma notificação close_notify. O PHP acusará isso como sendo "SSL: Fatal Protocol Error" quando tentar ler os dados. Para prevenir isso, o valor de error_reporting deve ser reduzido para um nível que não inclui avisos. para o nível que não emita warnings. O PHP 4.3.7 e seguintes conseguem detectar servidores IIS defeituosos quando você abre um stream utilizando o wrapper https:// e suprimirá os avisos. Se você está usando fsockopen() para criar um socket ssl://, a responsabilidade de detectar e suprimir esse aviso passa para você.

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() */
$meta_data stream_get_meta_data($fp);
foreach(
$meta_data['wrapper_data'] as $response) {

  
/* Were we redirected? */
  
if (substr(strtolower($response), 010) == 'location: ') {
    
/* update $url with where we were redirected to */
    
$url substr($response18);
  }

}

?>

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.

Nota: HTTPS is supported starting from PHP 4.3.0, if you have compiled in support for OpenSSL.

If you have set the from directive in php.ini, and do not define a From: header in the Context options and parameters, then this value will be sent as the From: header in the HTTP request.

Wrapper Summary
Attribute Supported
Restricted by allow_url_fopen Yes
Allows Reading Yes
Allows Writing No
Allows Appending No
Allows Simultaneous Reading and Writing N/A
Supports stat() No
Supports unlink() No
Supports rename() No
Supports mkdir() No
Supports rmdir() No

Custom headers may be sent with an HTTP request prior to version 5 by taking advantage of a side-effect in the handling of the user_agent INI setting. Set user_agent to any valid string (such as the default PHP/version setting) followed by a carriage-return/line-feed pair and any additional headers. This method works in PHP 4 and all later versions.

Exemplo #1 Sending custom headers with an HTTP request

<?php
ini_set
('user_agent'"PHP\r\nX-MyCustomHeader: Foo");

$fp fopen('http://www.example.com/index.php''r');
?>

Results in the following request being sent:

GET /index.php HTTP/1.0
Host: www.example.com
User-Agent: PHP
X-MyCustomHeader: Foo


List of Supported Protocols/Wrappers
PHP Manual