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function is not described

update_attached_file() WP 2.1.0

Update attachment file path based on attachment ID.

Used to update the file path of the attachment, which uses post meta name '_wp_attached_file' to store the path of the attachment.

Hooks in function
Return

true/false. True on success, false on failure.

Usage

update_attached_file( $attachment_id, $file );
$attachment_id(int) (required)
Attachment ID.
$file(string) (required)
File path for the attachment.

Code of update attached file: wp-includes/post.php VER 5.1.1

<?php
function update_attached_file( $attachment_id, $file ) {
	if ( ! get_post( $attachment_id ) ) {
		return false;
	}

	/**
	 * Filters the path to the attached file to update.
	 *
	 * @since 2.1.0
	 *
	 * @param string $file          Path to the attached file to update.
	 * @param int    $attachment_id Attachment ID.
	 */
	$file = apply_filters( 'update_attached_file', $file, $attachment_id );

	if ( $file = _wp_relative_upload_path( $file ) ) {
		return update_post_meta( $attachment_id, '_wp_attached_file', $file );
	} else {
		return delete_post_meta( $attachment_id, '_wp_attached_file' );
	}
}