# Name

`MPI_Get_library_version` - Returns a string of the current Open MPI
version

# Syntax

## C Syntax

```c
#include <mpi.h>

int MPI_Get_library_version(char *version, int *resultlen)
```

## Fortran Syntax

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

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

## Fortran 2008 Syntax

```fortran
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
```

# Output Parameters

* `version` : A string containing the Open MPI version (string).
* `resultlen` : Length (in characters) of result returned in `version` (integer).
* `IERROR` : Fortran only: Error status (integer).

# Description

This routine returns a string representing the `version` of the MPI
library. The `version` argument is a character string for maximum
flexibility.

The number of characters actually written is returned in the output
argument, `resultlen`. In C, a '0' character is additionally stored
at `version[resultlen]`. The `resultlen` cannot be larger than
(`MPI_MAX_LIBRARY_VERSION_STRING` - 1). In Fortran, `version` is padded on
the right with blank characters. The `resultlen` cannot be larger than `MPI_MAX_LIBRARY_VERSION_STRING`.

# Note

The `version` string that is passed must be at least
`MPI_MAX_LIBRARY_VERSION_STRING` characters long.

`MPI_Get_library_version` is one of the few functions that can be called
before `MPI_Init` and after `MPI_Finalize.`

# Errors

Almost all MPI routines return an error value; C routines as the value
of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for
I/O function errors. The error handler may be changed with
`MPI_Comm_set_errhandler`; the predefined error handler `MPI_ERRORS_RETURN`
may be used to cause error values to be returned. Note that MPI does not
guarantee that an MPI program can continue past an error.

# See Also

[`MPI_Get_version`(3)](MPI_Get_version.html)