#include "mpi.h" int MPI_Attr_get ( MPI_Comm comm, int keyval, void *attr_value, int *flag )
|comm||communicator to which attribute is attached (handle)
|keyval||key value (integer)
|attr_value||attribute value, unless flag = false
|flag||true if an attribute value was extracted; false if no attribute is
associated with the key
All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type INTEGER in Fortran.
The attr_value in Fortran is a pointer to a Fortran integer, not a pointer to a void *.
All MPI routines (except MPI_Wtime and MPI_Wtick) return an error value; C routines as the value of the function and Fortran routines in the last argument. Before the value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job. The error handler may be changed with MPI_Errhandler_set; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarentee that an MPI program can continue past an error.