use SystemTime;
/// Return current Unix time in whole seconds.
/// Whole seconds between the Unix epoch and `moment`.
///
/// A clock that reads before 1970 — as happens on a VM or container booted
/// with a dead real-time clock — would make `duration_since` return an error.
/// We clamp those to `0` rather than panicking so the daemon stays up until
/// the clock is corrected.