---
name: "shmem_longlong_add.openmpi"
section: "3"
platform: "linux"
package: "openmpi-doc"
version: "5.0.7-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/shmem_longlong_add.openmpi"
---

# shmem\_longlong\_add.openmpi(3)

[*shmem\_int\_add*(3)](/shmem_int_add/3.md), shmem\_int4\_add(3), shmem\_int8\_add(3), [*shmem\_long\_add*(3)](/shmem_long_add/3.md), [*shmem\_longlong\_add*(3)](/shmem_longlong_add/3.md) - Performs an atomic add operation.

## SYNOPSIS

C or C++:

```
#include <mpp/shmem.h>
void shmem_int_add(int *target, int value, int pe)
void shmem_long_add(long *target, long value, int pe)
void shmem_longlong_add(long long *target, long long value,
  int pe)
```

Fortran:

```
include 'mpp/shmem.h'
INTEGER pe
CALL SHMEM_INT4_ADD(target, value, pe)
CALL SHMEM_INT8_ADD(target, value, pe)
```

## DESCRIPTION

The atomic add routines add **value** to the data at address **target** on PE **pe**. The operation completes without the possibility of another process updating target between the time of the fetch and the update.

The arguments are as follows:

- **target**

  The remotely accessible integer data object to be updated on the remote PE. If you are using C/C++, the type of target should match that implied in the SYNOPSIS section. If you are using the Fortran compiler, it must be of type integer with an element size of 4 bytes for SHMEM\_INT4\_ADD and 8 bytes for SHMEM\_INT8\_ADD.

- **value**

  The value to be atomically added to target. If you are using C/C++, the type of value should match that implied in the SYNOPSIS section. If you are using Fortran, it must be of type integer with an element size of target.

- **pe**

  An integer that indicates the PE number upon which target is to be updated. If you are using Fortran, it must be a default integer value.

## NOTES

The term remotely accessible is defined in [*intro\_shmem*(3)](/intro_shmem/3.md).

**SEE ALSO:**

[*intro\_shmem*(3)](/intro_shmem/3.md) *shmem\_cache*(3)

## COPYRIGHT

2003-2025, The Open MPI Community