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function is not described

xmlrpc_pingback_error() WP 3.5.1

Default filter attached to xmlrpc_pingback_error.

Returns a generic pingback error code unless the error code is 48, which reports that the pingback is already registered.

No Hooks.

Return

IXR_Error.

Usage

xmlrpc_pingback_error( $ixr_error );
$ixr_error(IXR_Error) (required)

Changelog

Since 3.5.1 Introduced.

Code of xmlrpc pingback error: wp-includes/comment.php WP 5.2.2

<?php
function xmlrpc_pingback_error( $ixr_error ) {
	if ( $ixr_error->code === 48 ) {
		return $ixr_error;
	}
	return new IXR_Error( 0, '' );
}