MPI_Transfer_of_handles(3)MPI_Transfer_of_handles(3)NAME
MPI_Transfer_of_handles - Transfers a Fortran handle (which is an
integer) to a C handle, and vice versa.
SYNOPSIS
C:
#include <mpi.h>
MPI_Fint MPI_Comm_c2f ( comm )
MPI_Comm *comm;
MPI_Comm MPI_Comm_f2c ( comm )
MPI_Fint *comm;
MPI_Fint MPI_Type_c2f ( datatype )
MPI_Datatype *datatype;
MPI_Datatype MPI_Type_f2c ( datatype )
MPI_Fint *datatype;
MPI_Fint MPI_Group_c2f ( group )
MPI_Group *group;
MPI_Group MPI_Group_f2c ( group )
MPI_Fint *group;
MPI_Fint MPI_Request_c2f ( request )
MPI_Request *request;
MPI_Request MPI_Request_f2c ( request )
MPI_Fint *request;
MPI_Fint MPI_Win_c2f ( win )
MPI_Win *win;
MPI_Win MPI_Win_f2c ( win )
MPI_Fint *win;
MPI_Fint MPI_Op_c2f ( FIop )
MPI_Op *op;
STANDARDS
This release implements the MPI 2.0 standard, as documented by the MPI
Forum in the July 1997 release of MPI: A Message Passing Interface
Standard.
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MPI_Transfer_of_handles(3)MPI_Transfer_of_handles(3)DESCRIPTION
The MPI_Transfer_of_handles functions convert from an integer Fortran
handle to a C handle, and from a C handle to an integer Fortran handle.
You can pass handles between Fortran and C or C++ by using an explicit C
wrapper to convert Fortran handles to C handles. There is no direct
access to C or C++ handles in Fortran.
You can pass handles between C and C++ by using overloaded C++ operators
called from C++ code. There is no direct access to C++ objects from C.
The type definition, MPI_Fint, is provided in C and C++ for an integer of
the size that matches a Fortran INTEGER type. Usually, MPI_Fint will be
equivalent to int.
The MPI_Transfer_of_handles function descriptions and the parameters they
accept are as follows:
MPI_Comm_f2c returns a C handle to a communicator. If the comm parameter
is a valid Fortran handle to a communicator, MPI_Comm_f2c returns a valid
C handle to that same communicator. If the value of comm is MPI_COMM_NULL
(Fortran value), MPI_Comm_f2c returns a null C handle. If comm is an
invalid Fortran handle, MPI_Comm_f2c returns an invalid C handle.
MPI_Comm_c2f translates a C communicator handle into a Fortran handle to
the same communicator. It maps a null handle into a null handle and an
invalid handle into an invalid handle.
MPI_Type_f2c returns a C handle to a datatype. If the datatype parameter
is a valid Fortran handle to a datatype, MPI_Type_f2c returns a valid C
handle to that same datatype. If the value of datatype is
MPI_DATATYPE_NULL (Fortran value), MPI_Type_f2c returns a null C handle.
If datatype is an invalid Fortran handle, MPI_Type_f2c returns an invalid
C handle.
MPI_Type_c2f translates a C datatype handle into a Fortran handle to the
same datatype. It maps a null handle into a null handle and an invalid
handle into an invalid handle.
MPI_Group_f2c returns a C handle to a group. If the group parameter is a
valid Fortran handle to a group, MPI_Group_f2c returns a valid C handle
to that same group. If the value of group is MPI_GROUP_NULL (Fortran
value), MPI_Group_f2c returns a null C handle. If group is an invalid
Fortran handle, MPI_Group_f2c returns an invalid C handle.
MPI_Group_c2f translates a C group handle into a Fortran handle to the
same group. It maps a null handle into a null handle and an invalid
handle into an invalid handle.
MPI_Request_f2c returns a C handle to a request. If the request
parameter is a valid Fortran handle to a request, MPI_request_f2c returns
a valid C handle to that same request. If the value of request is
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MPI_Transfer_of_handles(3)MPI_Transfer_of_handles(3)
MPI_REQUEST_NULL (Fortran value), MPI_Request_f2c returns a null C
handle. If request is an invalid Fortran handle, MPI_Request_f2c returns
an invalid C handle.
MPI_Request_c2f translates a C request handle into a Fortran handle to
the same request. It maps a null handle into a null handle and an invalid
handle into an invalid handle.
MPI_Win_f2c returns a C handle to a window. If the win parameter is a
valid Fortran handle to a window, MPI_Win_f2c returns a valid C handle to
that same window. If the value of win is MPI_WIN_NULL (Fortran value),
MPI_Win_f2c returns a null C handle. If win is an invalid Fortran
handle, MPI_Win_f2c returns an invalid C handle.
MPI_Win_c2f translates a C window handle into a Fortran handle to the
same window. It maps a null handle into a null handle and an invalid
handle into an invalid handle.
MPI_Op_f2c returns a C handle to an operator. If the op parameter is a
valid Fortran handle to an operator, MPI_Op_f2c returns a valid C handle
to that same operator. If the value of op is MPI_OP_NULL (Fortran value),
MPI_Op_f2c returns a null C handle. If op is an invalid Fortran handle,
MPI_Op_f2c returns an invalid C handle.
MPI_Op_c2f translates a C operator handle into a Fortran handle to the
same operator. It maps a null handle into a null handle and an invalid
handle into an invalid handle.
NOTES
All MPI routines in Fortran (except for MPI_Wtime(3) and MPI_Wtick(3) )
have an additional ierr argument at the end of the argument list. ierr
is an integer and has the same meaning as the return value of the routine
in C. In Fortran, MPI routines are subroutines and are invoked with the
CALL statement. Additionally, in Fortran, all MPI objects (for example,
MPI_Datatype and MPI_Comm) are of type integer.
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