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filter is not described

http_request_host_is_external filter-hook . WP 3.6.0

Check if HTTP request is external or not.

Allows to change and allow external requests for the HTTP request.

Usage

add_filter( 'http_request_host_is_external', 'filter_function_name_4116', 10, 3 );
function filter_function_name_4116( $external, $host, $url ){
	// filter...

	return $external;
}
$external(true/false)
Whether HTTP request is external or not.
$host(string)
Host name of the requested URL.
$url(string)
Requested URL.

Changelog

Since 3.6.0 Introduced.

Where the hook is called

wp_http_validate_url()
http_request_host_is_external
wp-includes/http.php 574
if ( ! apply_filters( 'http_request_host_is_external', false, $host, $url ) ) {

Where in WP core the hook is used

wp-includes/default-filters.php 266
add_filter( 'http_request_host_is_external', 'allowed_http_request_hosts', 10, 2 );
wp-includes/ms-default-filters.php 128
add_filter( 'http_request_host_is_external', 'ms_allowed_http_request_hosts', 20, 2 );