SHMEM_CHAR_GET_NBI(3)

🎀 SHMEM_CHAR_GET_NBI(3) 🎀

okay bestie, welcome to the Open MPI manual page for the nonblocking get girlies 💅 this is the gang:

• shmem_getmem_nbi
• shmem_char_get_nbi
• shmem_short_get_nbi
• shmem_int_get_nbi
• shmem_long_get_nbi
• shmem_longlong_get_nbi
• shmem_float_get_nbi
• shmem_double_get_nbi
• shmem_longdouble_get_nbi
• shmem_get8_nbi
• shmem_get16_nbi
• shmem_get32_nbi
• shmem_get64_nbi
• shmem_get128_nbi

and what do they do?? They give you a method for copying data from a contiguous remote data object on the PE you specified over to your local data object. nonblocking behavior, we love to see it ✨

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✨ SYNOPSIS ✨

C or C++:

#include <mpp/shmem.h>

void shmem_getmem_nbi(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_char_get(char *dest, const char *source,
  size_t nelems, int pe)

void shmem_short_get(short *dest, const short *source,
  size_t nelems, int pe)

void shmem_int_get(int *dest, const int *source,
  size_t nelems, int pe)

void shmem_long_get(long *dest, const long *source,
  size_t nelems, int pe)

void shmem_longlong_get(long long *dest, const long long *source,
  size_t nelems, int pe)

void shmem_float_get(float *dest, const float *source,
  size_t nelems, int pe)

void shmem_double_get(double *dest, const double *source,
  size_t nelems, int pe)

void shmem_longdouble_get(long double *dest, const long double *source,
  size_t nelems, int pe)

void shmem_get8(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_get16(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_get32(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_get64(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_get128(void *dest, const void *source,
  size_t nelems, int pe)

Fortran:

INCLUDE "mpp/shmem.fh"

INTEGER nelems, pe

CALL SHMEM_GETMEM_NBI(dest, source, nelems, pe)

CALL SHMEM_CHARACTER_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_COMPLEX_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_DOUBLE_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_INTEGER_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_LOGICAL_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_REAL_GET_NBI(dest, source, nelems, pe)

CALL SHMEM_GET4_NBI(dest, source, nelems, pe)

CALL SHMEM_GET8_NBI(dest, source, nelems, pe)

CALL SHMEM_GET32_NBI(dest, source, nelems, pe)

CALL SHMEM_GET64_NBI(dest, source, nelems, pe)

CALL SHMEM_GET128_NBI(dest, source, nelems, pe)

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💖 DESCRIPTION 💖

So the get routines are your little copy-paste fairies 🧚 — they take a contiguous symmetric data object from a different PE and put it in a contiguous data object on your local PE. Big slay.

The way that these return: they come back right after posting the operation. Not after the data shows up. That distinction is the whole plot twist. The operation counts as complete only after a subsequent call to shmem_quiet. And at the completion of shmem_quiet, the data has been delivered to the dest array on the local PE. No cap 💅

The arguments are as follows:

• dest — Local data object to be updated.
• source — Data object on the PE identified by pe that contains the data to be copied. This data object must be remotely accessible.
• nelems — Number of elements in the target and source arrays. len must be of type integer. If you are using Fortran, it must be a constant, variable, or array element of default integer type.
• pe — PE number of the remote PE. pe must be of type integer. If you are using Fortran, it must be a constant, variable, or array element of default integer type.

If you are using Fortran, data types must be of default size. For example, a real variable must be declared as REAL, REAL*4, or REAL(KIND=4). fr fr, default size only 🌸

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📝 NOTES 📝

Wanna know what "remotely accessible" even means? Go read intro_shmem(3), it's defined there. 🦋

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🌟 EXAMPLES 🌟

Consider this simple example for Fortran. (it's giving vintage, but it's iconic)

PROGRAM REDUCTION
  REAL VALUES, SUM
  COMMON /C/ VALUES
  REAL WORK

  CALL START_PES(0) ! ALLOW ANY NUMBER OF PES
  VALUES = MY_PE() ! INITIALIZE IT TO SOMETHING
  CALL SHMEM_BARRIER_ALL
  SUM = 0.0
  DO I = 0,NUM_PES()-1
    CALL SHMEM_REAL_GET_NBI(WORK, VALUES, 1, I)
    CALL SHMEM_QUIET                ! wait for delivery
    SUM = SUM + WORK
  ENDDO
  PRINT *, 'PE ', MY_PE(), ' COMPUTED SUM=', SUM
  CALL SHMEM_BARRIER_ALL
END

See also:

intro_shmem(3) shmem_quiet(3)

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💌 COPYRIGHT 💌

Copyright 2003-2026, The Open MPI Community.

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okay that's the whole page, and yes I am obsessed with it 💖 this was the SHMEM_CHAR_GET_NBI(3) page from the Open MPI manual, 3rd section, last touched Sep 10, 2026 — mwah, go post some nonblocking gets and remember to shmem_quiet before you read your dest, bestie 👑✨