SHMEM_LONG_ADD(3)

💅 SHMEM_LONG_ADD(3) — an Open MPI bestie page 💅

okay so welcome to Open MPI’s SHMEM_LONG_ADD(3) page, and honestly it’s giving atomic-add main character energy ✨

🌸 NAME 🌸

These are the atomic add girlies, fr fr:

• shmem_int_add(3)
• shmem_int4_add(3)
• shmem_int8_add(3)
• shmem_long_add(3)
• shmem_longlong_add(3)

They perform an atomic add operation. periodt. 💅

✨ 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. no cap, that’s the whole vibe check 🫶

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. literally match the type, bestie 😭
• 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. slay, but keep those sizes aligned 💅
• 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. iconic little PE number, keep it default 🎀

🦋 NOTES 🦋

The term remotely accessible is defined in intro_shmem(3). iykyk 🌈

👑 SEE ALSO 👑

• intro_shmem(3)
• shmem_cache(3)

🍓 COPYRIGHT 🍓

2003-2026, The Open MPI Community

xoxo, Open MPI 💖 — source/version Open MPI, dated May 14, 2026, on this SHMEM_LONG_ADD(3) page. mwah! 🎀✨