if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {
log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));
err = -EWOULDBLOCK;
if (fd_lock >= 0 && flock(fd_lock, LOCK_SH|LOCK_NB) < 0) {
log_debug("Unable to flock(%s), skipping event handling: %m", udev_device_get_devnode(d));
err = -EWOULDBLOCK;