NAME

       MPI_Test_cancelled - Tests whether a request was canceled.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Test_cancelled(const MPI_Status *status, int *flag)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_TEST_CANCELLED(STATUS, FLAG, IERROR)
            LOGICAL   FLAG
            INTEGER   STATUS(MPI_STATUS_SIZE), IERROR

C++ Syntax

       #include <mpi.h>
       bool Status::Is_cancelled() const

INPUT PARAMETER

       status    Status object (status).

OUTPUT PARAMETERS

       flag      True if operation was cancelled (logical).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       Returns  flag  =  true if the communication associated with the status object was canceled
       successfully. In such a case, all other fields of  status  (such  as  count  or  tag)  are
       undefined.  Otherwise, returns flag = false. If a receive operation might be canceled, one
       should call MPI_Test_cancelled first, to check whether the operation was canceled,  before
       checking on the other fields of the return status.

NOTES

       Cancel can be an expensive operation that should be used only exceptionally.

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.

       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.