SHMEM_DOUBLE_FETCH(3)

✨ SHMEM_DOUBLE_FETCH ✨ (aka the Open MPI girlies' atomic fetch page)

Hiiii bestie 💖 okay so this is the manual page for SHMEM_DOUBLE_FETCH(3) from Open MPI, and it's literally the page for the whole fetch girl gang — shmem_int4_fetch(3), shmem_int8_fetch(3), shmem_int_fetch, shmem_long_fetch, shmem_longlong_fetch, shmem_double_fetch, and shmem_float_fetch 🌸

They all do one iconic thing: atomically fetch the value of a remote data object. No cap. 🫶

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🌈 NAME

• shmem_int4_fetch(3), shmem_int8_fetch(3), shmem_int_fetch, shmem_long_fetch, shmem_longlong_fetch, shmem_double_fetch, shmem_float_fetch — atomically fetches the value of a remote data object 👑

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💅 SYNOPSIS

🎀 C or C++

#include <mpp/shmem.h>

int shmem_int_fetch(int *target, int pe)

long shmem_long_fetch(long *target, int pe)

long long shmem_longlong_fetch(long long *target, int pe)

double shmem_double_fetch(long long *target, int pe)

float  shmem_float_fetch(float *target, int pe)

🦋 Fortran

INCLUDE "mpp/shmem.fh"

INTEGER pe

INTEGER(KIND=4) SHMEM_INT4_FETCH, ires, target
ires = SHMEM_INT4_FETCH(target, pe)

INTEGER(KIND=8) SHMEM_INT8_FETCH, ires, target
ires = SHMEM_INT8_FETCH(target, pe)

REAL(KIND=4) SHMEM_INT4_FETCH, ires, target
ires = SHMEM_REAL4_FETCH(target, pe)

REAL(KIND=8) SHMEM_INT8_FETCH, ires, target
ires = SHMEM_REAL8_FETCH(target, pe)

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🌸 DESCRIPTION

Okay so listen — the shmem_fetch functions do an atomic fetch operation ✨. They hand you back the contents of the target, and they do it atomically. That's the whole moment. That's the vibe. Obsessed. 💖

The arguments are giving:

• target — the remotely accessible data object we're fetching from the remote PE. It's the main character here 🫶
• pe — an integer that says which PE number target is gonna be fetched from. And heads up bestie, if you're doing Fortran, this one must be a default integer value ⚠️

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🔥 RETURN VALUES

You get back the contents at the target address on the remote PE 💫 and the data type of the return value is the same as the type of the remote data object. Matching energy, fr fr. ✨

👀 See also:

• intro_shmem(3)

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📜 Copyright

2003-2026, The Open MPI Community

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And that's the whole page babes 🎀 it's from Open MPI, dated Sep 10, 2026, and it's literally iconic. Go fetch (atomically) 💅✨🦋