header = notmuch_message_file_get_header (message_file, "message-id");
if (header && *header != '\0') {
message_id = _parse_message_id (message_file, header, NULL);
header = notmuch_message_file_get_header (message_file, "message-id");
if (header && *header != '\0') {
message_id = _parse_message_id (message_file, header, NULL);