_gfortran_caf_event_query (The GNU Fortran Compiler)

#### 7.2.22 `_gfortran_caf_event_query` — Query event count ¶

Synopsis:

  `void _gfortran_caf_event_query (caf_token_t token, size_t index, int image_index, int *count, int *stat)`

Description:

  Return the event count of the specified event variable.

Arguments:

  token | intent(in) An opaque pointer identifying the coarray.
  index | intent(in) Array index; first array index is 0. For scalars, it is always 0.
  image_index | intent(in) The ID of the remote image; must be a positive number; zero indicates the current image when accessed noncoindexed.
  count | intent(out) The number of events currently posted to the event variable.
  stat | intent(out) Stores the STAT=; may be NULL.

Notes:

  The typical use is to check the local event variable to only call `event_wait` when the data is available. However, a coindexed variable is permitted; there is no ordering or synchronization implied. It acts like an atomic fetch of the value of the event variable.