# Fortran Wiki event_query

## Description

event_query assignes the number of events to count which have been posted to the event variable and not yet been removed by calling event wait. When stat is present and the invocation was successful, it is assigned the value 0. If it is present and the invocation has failed, it is assigned a positive value and count is assigned the value $-1$.

## Standard

TS 18508 or later

Subroutine

## Syntax

call event_query(event, count [, stat])

## Arguments

• event - (intent(in)) Scalar of type event_type, defined in iso_fortran_env; shall not be coindexed.
• count - (intent(out))Scalar integer with at least the precision of default integer.
• stat - (optional) Scalar default-kind integer variable.

## Example

program atomic
use iso_fortran_env
implicit none
type(event_type) :: event_value_has_been_set[*]
integer :: cnt
if (this_image() == 1) then
call event_query(event_value_has_been_set, cnt)
if (cnt > 0) write(*,*) "Value has been set"
elseif (this_image() == 2) then
event post(event_value_has_been_set[1])
end if
end program atomic

category: intrinsics