/* Returns 0 upon success, -1 upon failure. */
if ((ret = tcsetattr(fd, TCSADRAIN, (struct termios *)backup)) < 0) {
sr_err("FD %d: Error restoring serial parameters: %s.",
/* Returns 0 upon success, -1 upon failure. */
if ((ret = tcsetattr(fd, TCSADRAIN, (struct termios *)backup)) < 0) {
sr_err("FD %d: Error restoring serial parameters: %s.",