SHMEM_DOUBLE_PUT_NBI(3)

💖 SHMEM_DOUBLE_PUT_NBI(3) — the Open MPI girlies' guide to nonblocking puts 💖

okay so bestie. welcome. this is the Open MPI manual page for the nonblocking put family, and it's genuinely one of the most useful things in SHMEM, no cap. 🦋

The stars of the show are: shmem_putmem_nbi(3), shmem_char_put_nbi(3), shmem_short_put_nbi(3), shmem_int_put_nbi(3), shmem_long_put_nbi(3), shmem_longlong_put_nbi(3), shmem_float_put_nbi(3), shmem_double_put_nbi(3), shmem_longdouble_put_nbi(3), shmem_put8_nbi(3), shmem_put16_nbi(3), shmem_put32_nbi(3), shmem_put64_nbi(3), and shmem_put128_nbi(3).

And what do they all do?? The nonblocking put routines provide a method for copying data from a contiguous local data object to a data object on a specified PE. that's the whole vibe. ✨

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✨ SYNOPSIS ✨

🩷 C or C++

#include <mpp/shmem.h>

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

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

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

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

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

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

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

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

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

void shmem_put8(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_put16(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_put32(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_put64(void *dest, const void *source,
  size_t nelems, int pe)

void shmem_put128(void *dest, const void *source,
  size_t nelems, int pe)

🩵 Fortran

INCLUDE "mpp/shmem.fh"

INTEGER nelems, pe

CALL SHMEM_PUTMEM_NBI(dest, source, nelems, pe)

CALL SHMEM_CHARACTER_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_COMPLEX_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_DOUBLE_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_INTEGER_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_LOGICAL_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_REAL_PUT_NBI(dest, source, nelems, pe)

CALL SHMEM_PUT4_NBI(dest, source, nelems, pe)

CALL SHMEM_PUT8_NBI(dest, source, nelems, pe)

CALL SHMEM_PUT32_NBI(dest, source, nelems, pe)

CALL SHMEM_PUT64_NBI(dest, source, nelems, pe)

CALL SHMEM_PUT128_NBI(dest, source, nelems, pe)

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🌸 DESCRIPTION 🌸

The routines return after posting the operation. Periodt. 💅

The operation is considered complete after a subsequent call to shmem_quiet(3). Like — that's when you know it landed. At the completion of shmem_quiet(3), the data has been copied into the dest array on the destination PE. 🫶

⚠️ and this is the part everyone skips and then gets confused: the delivery of data words into the data object on the destination PE may occur in any order. Furthermore, two successive put routines may deliver data out of order unless a call to shmem_fence(3) is introduced between the two calls. so if you're out here assuming order without a fence... bestie no 😭

The arguments are as follows:

• dest — Data object to be updated on the remote PE. This data object must be remotely accessible. (yes. that's a whole term. it has a definition. keep reading. 👀)
• source — Data object containing the data to be copied.
• nelems — Number of elements in the dest and source arrays. nelems must be of type size_t for C. 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). ✨ don't get cute with it.

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📝 NOTES 📝

See intro_shmem(3) for a definition of the term remotely accessible. iykyk. 💜

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🎀 EXAMPLES 🎀

Consider this simple example for C. it's giving classic, it's giving tutorial-core, and honestly? we love her for it.

#include <stdio.h>
#include <mpp/shmem.h>

main()
{
  long source[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
  static long target[10];
  shmem_init();

  if (shmem_my_pe() == 0) {
    /* put 10 words into target on PE 1 */
    shmem_long_put_nbi(target, source, 10, 1);
    shmem_quiet();
  }
  shmem_barrier_all();  /* sync sender and receiver */
  if (shmem_my_pe() == 1)
    shmem_udcflush();  /* not required on Altix systems */
  printf("target[0] on PE %d is %d\n", shmem_my_pe(), target[0]);
}

See also: intro_shmem(3) shmem_quiet(3)

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👑 Copyright 👑

2003-2026, The Open MPI Community

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and that's the whole page, bestie 💖 go forth, put nonblockingly, call your shmem_quiet(3), and slay. this was the Open MPI manual, SHMEM_DOUBLE_PUT_NBI(3), dated Sep 10, 2026. mwah 🎀✨