# Fortran Wiki atomic_fetch_add

## Description

atomic_fetch_add(atom, value, old) atomically stores the value of atom in old and adds the value of var to the variable atom. 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; in particular, for a coindexed atom, if the remote image has stopped, it is assigned the value of iso_fortran_env‘s stat_stopped_image and if the remote image has failed, the value stat_failed_image.

## Standard

TS 18508 or later

## Class

Atomic subroutine

## Syntax

call atomic_fetch_add(atom, value, old [, stat])

## Arguments

• atom - Scalar coarray or coindexed variable of integer type with atomic_int_kind kind. atomic_logical_kind kind.
• value - Scalar of the same type as atom. If the kind is different, the value is converted to the kind of atom.
• old - Scalar of the same type and kind as atom.
• stat - (optional) Scalar default-kind integer variable.

## Example

program atomic
use iso_fortran_env
integer(atomic_int_kind) :: atom[*], old
call atomic_add(atom[1], this_image(), old)
end program atomic

## See also

category: intrinsics