---
name: "MPI_Errhandler_create"
section: "3"
platform: "linux"
package: "openmpi"
version: "5.0.11-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/MPI_Errhandler_create"
---

# MPI\_Errhandler\_create(3)

*MPI\_Errhandler\_create* — Creates an MPI-style error handler — this routine is deprecated in favor of *MPI\_Comm\_create\_errhandler*.

## SYNTAX

### C Syntax

```
#include <mpi.h>
int MPI_Errhandler_create(MPI_Handler_function *function,
     MPI_Errhandler *errhandler)
```

### Fortran Syntax

```
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_ERRHANDLER_CREATE(FUNCTION, ERRHANDLER, IERROR)
     EXTERNAL        FUNCTION
     INTEGER ERRHANDLER, IERROR
```

## INPUT PARAMETER

- •

  **function**: User-defined error handling procedure.

## OUTPUT PARAMETERS

- •

  **errhandler**: MPI error handler (handle).

- •

  **ierror**: Fortran only: Error status (integer).

## DESCRIPTION

Note that use of this routine is *deprecated* as of MPI-2. Please use *MPI\_Comm\_create\_errhandler* instead.

Registers the user routine function for use as an MPI error handler. Returns in errhandler a handle to the registered error handler.

In the C language, the user routine should be a C function of type MPI\_Handler\_function, which is defined as

```
typedef void (MPI_Handler_function)(MPI_Comm *, int *, ...);
```

The first argument is the communicator in use. The second is the error code to be returned by the MPI routine that raised the error. If the routine would have returned MPI\_ERR\_IN\_STATUS, it is the error code returned in the status for the request that caused the error handler to be invoked. The remaining arguments are stdargs arguments whose number and meaning is implementation-dependent. An implementation should clearly document these arguments. Addresses are used so that the handler may be written in Fortran.

## NOTE

The *MPI Standard* states that an implementation may make the output value (errhandler) simply the address of the function. However, the action of *MPI\_Errhandler\_free* makes this impossible, since it is required to set the value of the argument to **MPI\_ERRHANDLER\_NULL**. In addition, the actual error handler must remain until all communicators that use it are freed.

## 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 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.

- •

  **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.

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.

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\_Comm\_create\_errhandler*

- •

  *MPI\_Comm\_get\_errhandler*

- •

  *MPI\_Comm\_set\_errhandler*

## COPYRIGHT

2003-2026, The Open MPI Community