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filter is not described

allowed_redirect_hosts filter-hook . WP 2.3.0

Filters the whitelist of hosts to redirect to.

Usage

add_filter( 'allowed_redirect_hosts', 'filter_function_name_5832', 10, 2 );
function filter_function_name_5832( $hosts, $host ){
	// filter...

	return $hosts;
}
$hosts(array)
An array of allowed hosts.
$host(true/false/string)
The parsed host; empty if not isset.

Where the hook is called

wp_validate_redirect()
wp-includes/pluggable.php 1371
$allowed_hosts = (array) apply_filters( 'allowed_redirect_hosts', array($wpp['host']), isset($lp['host']) ? $lp['host'] : '' );

Where the hook is used (in WP core)

wp-includes/ms-default-filters.php 50
add_filter( 'allowed_redirect_hosts', 'redirect_this_site' );