function download_open_export_file( $filename ) {
$filepath = \PressBooks\Export\Export::getExportFolder() . $filename;
if ( ! is_readable( $filepath ) ) {
// Cannot read file
wp_die( __( 'File not found', 'pressbooks-textbook' ) . ": $filename", '', array( 'response' => 404 ) );
}
// Force download
set_time_limit( 0 );
header( 'Content-Description: File Transfer' );
header( 'Content-Type: ' . \Pressbooks\Export\Export::mimeType( $filepath ) );
header( 'Content-Disposition: attachment; filename="' . $filename . '"' );
header( 'Content-Transfer-Encoding: binary' );
header( 'Expires: 0' );
header( 'Cache-Control: must-revalidate, post-check=0, pre-check=0' );
header( 'Pragma: public' );
header( 'Content-Length: ' . filesize( $filepath ) );
@ob_clean();
flush();
while ( @ob_end_flush() ); // Fix out-of-memory problem
readfile( $filepath );
exit;
}
