MPI_WIN_SET_INFO(3)

💖 MPI_WIN_SET_INFO(3) 💖

okay bestie, welcome to the Open MPI manual, page MPI_WIN_SET_INFO(3) — yes we're doing window info hints today and honestly? iconic. ✨

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🌸 NAME 🌸

MPI_Win_set_info — set window info hints, no cap 💅

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🦋 SYNTAX 🦋

💜 C Syntax

#include <mpi.h>

int MPI_Win_set_info(MPI_Win win, MPI_Info info)

💜 Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_WIN_SET_INFO(WIN, INFO, IERROR)
     INTEGER WIN, INFO, IERROR

💜 Fortran 2008 Syntax

USE mpi_f08
MPI_Win_set_info(win, info, ierror)
     TYPE(MPI_Win), INTENT(IN) :: win
     TYPE(MPI_Info), INTENT(IN) :: info
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

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🎀 INPUT PARAMETERS 🎀

• win — the window on which to set info hints. it's giving "the thing we're decorating" 🪟✨
• info — the info object holding the hints that are gonna be set on win. all the vibes live in here 🫶

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⭐ OUTPUT PARAMETERS ⭐

• ierror — Fortran only: error status, as an integer. the receipts, fr fr 🧾

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🌈 DESCRIPTION 🌈

so like — MPI_Win_set_info sets brand new values for the hints of the window associated with win. new hints, who dis. 👑

MPI_Win_set_info is a collective routine. and here's the tea: the info object may be different on each process 🫢 — BUT any info entries that an implementation requires to be the same on all processes must appear with the same value in each process's info object. like, matching fits or it doesn't work, periodt.

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💀 ERRORS 💀

almost all MPI routines return an error value, bestie. in C routines it's the return result of the function, and in Fortran routines it's the last argument. both paths lead to the same drama.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_Init / MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_Comm_spawn / MPI_Comm_spawn_multiple. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions. 😭

Open MPI includes three predefined error handlers that can be used:

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes. nuclear. 💥
• MPI_ERRORS_ABORT — an error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if MPI_Abort was called on that communicator. If called on a window or file, acts as if MPI_Abort was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process. very "depends on the context" of it 🫠
• MPI_ERRORS_RETURN — returns an error code to the application. the polite one 🎀

MPI applications can also implement their own error handlers by calling:

• MPI_Comm_create_errhandler then MPI_Comm_set_errhandler
• MPI_File_create_errhandler then MPI_File_set_errhandler
• MPI_Session_create_errhandler then MPI_Session_set_errhandler or at MPI_Session_init
• MPI_Win_create_errhandler then MPI_Win_set_errhandler

Note that MPI does not guarantee that an MPI program can continue past an error. so like, don't count on it to survive. 🙈

See the MPI man page for a full list of MPI error codes.

See the Error Handling section of the MPI-3.1 standard for more information.

See also:

• MPI_Win_get_info
• MPI_Info_create
• MPI_Info_set
• MPI_Info_free

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👑 Copyright 👑

2003-2026, The Open MPI Community

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and that's the whole page bestie, we ate and left no crumbs 💅✨ this was the MPI_WIN_SET_INFO(3) page from the Open MPI manual, dated Sep 10, 2026 — go set those hints, main character 🦋💖