SHMEM_LONG_FADD(3)

🦋 SHMEM_LONG_FADD(3) 🦋

okay bestie, welcome to this Open MPI manual page for SHMEM_LONG_FADD(3) — we’re talking atomic fetch-and-add on a remote data object, and the details below are literally all the details. no cap. 💅

💖 NAME 💖

shmem_int4_fadd(3), shmem_int8_fadd(3), shmem_int_fadd(3), shmem_long_fadd(3), shmem_longlong_fadd(3) — performs an atomic fetch-and-add operation on a remote data object.

✨ SYNOPSIS ✨

C or C++:

#include <mpp/shmem.h>

int shmem_int_fadd(int *target, int value, int pe)

long shmem_long_fadd(long *target, long value, int pe)

long long shmem_longlong_fadd(long long *target, longlong value,
            int pe)

Fortran:

INCLUDE "mpp/shmem.fh"

INTEGER pe

INTEGER(KIND=4) SHMEM_INT4_FADD, ires, target, value
ires = SHMEM_INT4_FADD(target, value, pe)

INTEGER(KIND=8) SHMEM_INT8_FADD, ires, target, value
ires = SHMEM_INT8_FADD(target, value, pe)

🎀 DESCRIPTION 🎀

The shmem_fadd functions perform an atomic fetch-and-add operation. An atomic fetch-and-add operation fetches the old target and adds value to target without the possibility of another process updating target between the time of the fetch and the update. These routines add value to target on Processing Element (PE) pe and return the previous contents of target as an atomic operation.

The arguments are as follows:

• target — the remotely accessible integer data object to be updated on the remote PE. The type of target should match that implied in the SYNOPSIS section.
• value — the value to be atomically added to target. The type of value should match that implied in the SYNOPSIS section.
• pe — an integer that indicates the PE number on 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). iykyk. 🫶

🌈 RETURN VALUES 🌈

The contents that had been at the target address on the remote PE prior to the atomic addition operation.

💅 SEE ALSO 💅

• intro_shmem(3)

👑 COPYRIGHT 👑

2003-2026, The Open MPI Community

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this Open MPI page is dated May 14, 2026 — go be iconic with your atomics, bestie 💅✨