wasi:clocks

Types

Functions

WIT

/// WASI Wall Clock is a clock API intended to let users query the current
/// time. The name "wall" makes an analogy to a "clock on the wall", which
/// is not necessarily monotonic as it may be reset.
///
/// It is intended to be portable at least between Unix-family platforms and
/// Windows.
///
/// A wall clock is a clock which measures the date and time according to
/// some external reference.
///
/// External references may be reset, so this clock is not necessarily
/// monotonic, making it unsuitable for measuring elapsed time.
///
/// It is intended for reporting the current date and time for humans.
@since(version = 0.2.0)
interface wall-clock {
  /// A time and date in seconds plus nanoseconds.
  @since(version = 0.2.0)
  record datetime {
    seconds: u64,
    nanoseconds: u32,
  }

  /// Read the current value of the clock.
  ///
  /// This clock is not monotonic, therefore calling this function repeatedly
  /// will not necessarily produce a sequence of non-decreasing values.
  ///
  /// The returned timestamps represent the number of seconds since
  /// 1970-01-01T00:00:00Z, also known as [POSIX's Seconds Since the Epoch],
  /// also known as [Unix Time].
  ///
  /// The nanoseconds field of the output is always less than 1000000000.
  ///
  /// [POSIX's Seconds Since the Epoch]: https://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xbd_chap04.html#tag_21_04_16
  /// [Unix Time]: https://en.wikipedia.org/wiki/Unix_time
  @since(version = 0.2.0)
  now: func() -> datetime;

  /// Query the resolution of the clock.
  ///
  /// The nanoseconds field of the output is always less than 1000000000.
  @since(version = 0.2.0)
  resolution: func() -> datetime;
}