This class provides methods for initializing, finalizing, and querying the global MPI session. More...

#include <Teuchos_GlobalMPISession.hpp>

Static Private Member Functions
static void	initialize (std::ostream *out)
Static Private Attributes
static bool	haveMPIState_ = false
static bool	mpiIsFinalized_ = false
static int	rank_ = 0
static int	nProc_ = 1
Public constructor and destructor
	GlobalMPISession (int argc, char *argv, std::ostream out=&std::cout)
	Calls `MPI_Init()` if MPI is enabled.
	~GlobalMPISession ()
	Calls `MPI_Finalize()` if MPI is enabled.
Static functions
static bool	mpiIsInitialized ()
static bool	mpiIsFinalized ()
static int	getRank ()
	Returns the process rank relative to `MPI_COMM_WORLD`
static int	getNProc ()
	Returns the number of processors relative to `MPI_COMM_WORLD`

Detailed Description

This class provides methods for initializing, finalizing, and querying the global MPI session.

This class is primarilly designed to insulate basic main() program type of code from having to know if MPI is enabled or not.

ToDo: Give examples!

Definition at line 52 of file Teuchos_GlobalMPISession.hpp.

Constructor & Destructor Documentation

Teuchos::GlobalMPISession::GlobalMPISession	(	int *	argc,
		char ***	argv,
		std::ostream *	out = `&std::cout`
	)

Calls MPI_Init() if MPI is enabled.

Parameters:

argc	[in] Argment passed into `main(argc,argv)`
argv	[in] Argment passed into `main(argc,argv)`
out	[in] If `out!=NULL`, then a small message on each processor will be printed to this stream. The default is `&std::cout`.

If the option --teuchos-suppress-startup-banner is found, the this option will be removed from argv[] before being passed to MPI_Init(...) and the startup output message to *out will be suppressed.

Warning! This constructor can only be called once per executable or an error is printed to *out and an std::exception will be thrown!

Definition at line 39 of file Teuchos_GlobalMPISession.cpp.

Teuchos::GlobalMPISession::~GlobalMPISession ( )

Calls MPI_Finalize() if MPI is enabled.

Definition at line 100 of file Teuchos_GlobalMPISession.cpp.

Member Function Documentation

bool Teuchos::GlobalMPISession::mpiIsInitialized ( ) [static]

Return if MPI is initialized or not.

Definition at line 114 of file Teuchos_GlobalMPISession.cpp.

bool Teuchos::GlobalMPISession::mpiIsFinalized ( ) [static]

Return if MPI has already been finalized.

Definition at line 120 of file Teuchos_GlobalMPISession.cpp.

int Teuchos::GlobalMPISession::getRank ( ) [static]

Returns the process rank relative to MPI_COMM_WORLD

Returns 0 if MPI is not enabled.

Note, this function can be called even if the above constructor was never called so it is safe to use no matter how MPI_Init() got called (but it must have been called somewhere).

Definition at line 125 of file Teuchos_GlobalMPISession.cpp.

int Teuchos::GlobalMPISession::getNProc ( ) [static]

Returns the number of processors relative to MPI_COMM_WORLD

Returns 1 if MPI is not enabled.

Note, this function can be called even if the above constructor was never called so it is safe to use no matter how MPI_Init() got called (but it must have been called somewhere).

Definition at line 132 of file Teuchos_GlobalMPISession.cpp.

void Teuchos::GlobalMPISession::initialize ( std::ostream * out ) [static, private]

Definition at line 140 of file Teuchos_GlobalMPISession.cpp.