MPI_WIN_SET_INFO(3)

💅 MPI_Win_set_info 💅

okay so bestie, welcome to the Open MPI glow-up of MPI_Win_set_info — the routine that's literally just "hey window, here are some new hints, take notes 📝". She's collective, she's got three whole language flavors, and she's about to be your new fave. Let's go 🫶

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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 we're setting info hints on, aka the main character of this whole call 🪟✨
• info — the info object carrying the hints that get set on win, like a little gift basket of settings 🎁

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🌈 OUTPUT PARAMETERS 🌈

• ierror — Fortran only, bestie: the error status, and it's an integer 💀

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🌸 DESCRIPTION 🌸

So MPI_Win_set_info sets new values for the hints of the window associated with win. That's it, that's the vibe. 🎀

Important though: MPI_Win_set_info is a collective routine. The info object may be different on each process — very "everyone's an individual, let them express themselves" 💅 — but any info entries that an implementation requires to have identical values on all processes must appear with the same value in each process's info object. No cap, that part is not optional 🙈

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🧚 ERRORS 🧚

okay so this is the long section but it's lowkey important so we're doing all of it, no skipping ⭐

Almost all MPI routines return an error value — C routines as the return result of the function, and Fortran routines in the last argument. 📬

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. 💀 dramatic but that's her
• 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. 🔥
• MPI_ERRORS_RETURN — Returns an error code to the application. polite queen 🎀

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… plan accordingly bestie 🙈

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. 💜

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👑 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, iykyk 💅 go set some info hints, you're gonna slay ✨ — written up on the Sep 11, 2026 edition of this Open MPI page, mwah 🫶🎀