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filter is not described

pingback_ping_source_uri filter-hook . WP 3.6.0

Filters the pingback source URI.

Usage

add_filter( 'pingback_ping_source_uri', 'filter_function_name_9321', 10, 2 );
function filter_function_name_9321( $pagelinkedfrom, $pagelinkedto ){
	// filter...

	return $pagelinkedfrom;
}
$pagelinkedfrom(string)
URI of the page linked from.
$pagelinkedto(string)
URI of the page linked to.

Where the hook is called

wp_xmlrpc_server::pingback_ping()
wp-includes/class-wp-xmlrpc-server.php 6340
$pagelinkedfrom = apply_filters( 'pingback_ping_source_uri', $pagelinkedfrom, $pagelinkedto );

Where the hook is used (in WP core)

wp-includes/default-filters.php 248
add_filter( 'pingback_ping_source_uri', 'pingback_ping_source_uri' );