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filter is not described

xmlrpc_pingback_error filter-hook . WP 3.5.1

Filters the XML-RPC pingback error return.

Usage

add_filter( 'xmlrpc_pingback_error', 'filter_function_name_6865' );
function filter_function_name_6865( $error ){
	// filter...

	return $error;
}
$error(IXR_Error)
An IXR_Error object containing the error code and message.

Where the hook is called

wp_xmlrpc_server::pingback_error()
wp-includes/class-wp-xmlrpc-server.php 6588
return apply_filters( 'xmlrpc_pingback_error', new IXR_Error( $code, $message ) );

Where the hook is used (in WP core)

wp-includes/default-filters.php 249
add_filter( 'xmlrpc_pingback_error', 'xmlrpc_pingback_error' );