MPI_ABORT(3)

💅 NAME 💅

MPI_Abort — okay so bestie, this one terminates the MPI execution environment, periodt. This page is from the Open MPI manual, and it's kind of a big deal.

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✨ SYNTAX ✨

🧸 C Syntax

#include <mpi.h>

int MPI_Abort(MPI_Comm comm, int errorcode)

🎀 Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_ABORT(COMM, ERRORCODE, IERROR)
     INTEGER         COMM, ERRORCODE, IERROR

🦋 Fortran 2008 Syntax

USE mpi_f08
MPI_Abort(comm, errorcode, ierror)
     TYPE(MPI_Comm), INTENT(IN) :: comm
     INTEGER, INTENT(IN) :: errorcode
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

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🌸 INPUT PARAMETERS 🌸

• comm — the communicator of tasks to abort. Like, these are the ones getting the vibe check.
• errorcode — the error code to return to the invoking environment. It's giving "here's the receipt."

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🫶 OUTPUT PARAMETER 🫶

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

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🔥 DESCRIPTION 🔥

So this routine makes a “best attempt” to abort all tasks in the group of comm. It does not require that the invoking environment take any action with the error code. But a UNIX or POSIX environment should handle this as a return errorcode from the main program or an abort (errorcode). Slay for standards, honestly.

The long-term goal of the Open MPI implementation is to terminate all processes in all tasks that contain a process in comm, and the error code is not returned to the invoking environment. Right now, that isn’t fully implemented, and MPI_Abort will terminate the entire job. No cap, it's a whole-job situation at the moment.

🚨 Note: all associated processes are sent a SIGTERM. That's the signal, bestie — not a drill.

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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. Iconic little language difference, honestly.

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. That's the whole chain, bestie — don't skip steps.

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

• MPI_ERRORS_ARE_FATAL — causes the program to abort all connected MPI processes. Very main-character exit.
• 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. Polite-ish.

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, sometimes it's just over.

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. Iykyk, go read the standard when you're feeling fancy.

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👑 COPYRIGHT 👑

2003-2026, The Open MPI Community

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mwah 💋 this iconic little page is from Open MPI, dated Sep 11, 2026 — that's the source/version and date, bestie. Now go forth and abort responsibly. 🦋✨