.\" -*- nroff -*-
.\" Copyright (c) 2010-2015 Cisco Systems, Inc.  All rights reserved.
.\" Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.\" $COPYRIGHT$
.TH MPI_Initialized 3 "Sep 30, 2023" "4.1.6" "Open MPI"
.SH NAME
\fBMPI_Initialized\fP \- Checks whether MPI has been initialized

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Initialized(int *\fIflag\fP)

.fi
.SH Fortran Syntax
.nf
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_INITIALIZED(\fIFLAG, IERROR\fP)
	LOGICAL	\fIFLAG\fP
	INTEGER	\fIIERROR\fP

.fi
.SH Fortran 2008 Syntax
.nf
USE mpi_f08
MPI_Initialized(\fIflag\fP, \fIierror\fP)
	LOGICAL, INTENT(OUT) :: \fIflag\fP
	INTEGER, OPTIONAL, INTENT(OUT) :: \fIierror\fP

.fi
.SH C++ Syntax
.nf
#include <mpi.h>
bool Is_initialized()

.fi
.SH OUTPUT PARAMETERS
.ft R
.TP 1i
flag
True if MPI has been initialized, and false otherwise (logical).
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
This routine may be used to determine whether MPI has been
initialized.  It is one of a small number of routines that may be
called before MPI is initialized and after MPI has been finalized
(MPI_Finalized is another).

.SH ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object.
.sp
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.

.SH SEE ALSO
.ft R
.nf
MPI_Init
MPI_Init_thread
MPI_Finalize
MPI_Finalized