- if ( $upload_err = apply_filters( 'pre_upload_error', false ) )
- return new IXR_Error(500, $upload_err);
+ /**
+ * Filter whether to preempt the XML-RPC media upload.
+ *
+ * Passing a truthy value will effectively short-circuit the media upload,
+ * returning that value as a 500 error instead.
+ *
+ * @since 2.1.0
+ *
+ * @param bool $error Whether to pre-empt the media upload. Default false.
+ */
+ if ( $upload_err = apply_filters( 'pre_upload_error', false ) ) {
+ return new IXR_Error( 500, $upload_err );
+ }