MPI_GET_LIBRARY_VERSION(3)

🌸 NAME 🌸

MPI_Get_library_version — returns a string of the current Open MPI version 💖 (yep bestie, you're on the MPI_GET_LIBRARY_VERSION(3) page, welcome, sit with me 🫶)

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📜 SYNTAX 📜

C Syntax

#include <mpi.h>

int MPI_Get_library_version(char *version, int *resultlen)

Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'

MPI_GET_LIBRARY_VERSION(VERSION, RESULTLEN, IERROR)
    CHARACTER*(*)   NAME
    INTEGER RESULTLEN, IERROR

Fortran 2008 Syntax

USE mpi_f08

MPI_Get_library_version(version, resulten, ierror)
    CHARACTER(LEN=MPI_MAX_LIBRARY_VERSION_STRING), INTENT(OUT) :: version
    INTEGER, INTENT(OUT) :: resultlen
    INTEGER, OPTIONAL, INTENT(OUT) :: ierror

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🎁 OUTPUT PARAMETERS 🎁

• version — a string holding the Open MPI version (string). Literally just vibes in character-array form ✨
• resultlen — the length (in characters) of the result returned in version (integer).
• ierror — Fortran only: error status (integer).

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💅 DESCRIPTION 💅

okay so this routine hands you back a string representing the version of the MPI library. The version argument is a character string, because maximum flexibility, periodt. 👑

The number of characters actually written gets returned in the output argument resultlen. In C, a '0' character is additionally stored at version[resultlen]. And no, resultlen cannot be larger than (MPI_MAX_LIBRARY_VERSION_STRING - 1). In Fortran, version gets padded on the right with blank characters, and resultlen cannot be larger than MPI_MAX_LIBRARY_VERSION_STRING. 🦋

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✨ NOTE ✨

The version string you pass in must be at least MPI_MAX_LIBRARY_VERSION_STRING characters long. No shortcuts, bestie. 💀

MPI_Get_library_version is one of the few functions that can be called before MPI_Init and after MPI_Finalize. Iconic behaviour honestly. 🔥

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💀 ERRORS 💀

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 that error value comes back, the current MPI error handler associated with the communication object (e.g., communicator, window, file) gets 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 or MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. That 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 the info key to MPI_Comm_spawn or 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 ships three predefined error handlers you can use: 🎀

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes.
• 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, it 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, it aborts only the local process.
• MPI_ERRORS_RETURN — returns an error code to the application. 🫶

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. Like, at all. 🚨

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_Get_version 💫

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📜 COPYRIGHT 📜

2003-2026, The Open MPI Community

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and that's the whole page bestie, no cap, you ate it 🍓💜 — this one came straight out of the Open MPI manual, dated Sep 10, 2026, filed under MPI_GET_LIBRARY_VERSION(3). go forth and version-check, mwah 💅✨