MPI_REQUEST_F2C(3)

MPI_Comm_f2c <#mpi-comm-f2c>, MPI_Comm_c2f <#mpi-comm-c2f>, MPI_File_f2c <#mpi-file-f2c>, MPI_File_c2f <#mpi-file-c2f>, MPI_Info_f2c <#mpi-info-f2c>, MPI_Info_c2f <#mpi-info-c2f>, MPI_Message_f2c <#mpi-message-f2c>, MPI_Message_c2f <#mpi-message-c2f>, MPI_Op_f2c <#mpi-op-f2c>, MPI_Op_c2f <#mpi-op-c2f>, MPI_Request_f2c, MPI_Request_c2f <#mpi-request-c2f>, MPI_Type_f2c <#mpi-type-f2c>, MPI_Type_c2f <#mpi-type-c2f>, MPI_Win_f2c <#mpi-win-f2c>, MPI_Win_c2f <#mpi-win-c2f> - Translates a C handle into a Fortran handle, or vice versa.

SYNTAX

  C Syntax

            #include <mpi.h>

            MPI_Comm MPI_Comm_f2c(MPI_Fint comm)
            MPI_Fint MPI_Comm_c2f(MPI_Comm comm)

            MPI_File MPI_File_f2c(MPI_Fint file)
            MPI_Fint MPI_File_c2f(MPI_File file)

            MPI_Group MPI_Group_f2c(MPI Fint group)
            MPI_Fint MPI_Group_c2f(MPI Group group)

            MPI_Info MPI_Info_f2c(MPI_Fint info)
            MPI_Fint MPI_Info_c2f(MPI_Info info)

            MPI_Message MPI_Message_f2c(MPI_Fint message)
            MPI_Fint MPI_Message_c2f(MPI_Message message)

            MPI_Op MPI_Op_f2c(MPI_Fint op)
            MPI_Fint MPI_Op_c2f(MPI_Op op)

            MPI_Request MPI_Request_f2c(MPI_Fint request)
            MPI_Fint MPI_Request_c2f(MPI_Request request)

            MPI_Datatype MPI_Type_f2c(MPI_Fint datatype)
            MPI_Fint MPI_Type_c2f(MPI_Datatype datatype)

            MPI_Win MPI_Win_f2c(MPI_Fint win)
            MPI_Fint MPI_Win_c2f(MPI_Win win)

DESCRIPTION

Handles are passed between Fortran and C by using an explicit C wrapper to convert Fortran handles to C handles. There is no direct access to C handles in Fortran. The type definition MPI_Fint is provided in C for an integer of the size that matches a Fortran INTEGER; usually, MPI_Fint will be equivalent to int. The handle translation functions are provided in C to convert from a Fortran handle (which is an integer) to a C handle, and vice versa.

For example, if comm is a valid Fortran handle to a communicator, then MPI_Comm_f2c <#mpi-comm-f2c> returns a valid C handle to that same communicator; if comm = MPI_COMM_NULL (Fortran value), then MPI_Comm_f2c <#mpi-comm-f2c> returns a null C handle; if comm is an invalid Fortran handle, then MPI_Comm_f2c <#mpi-comm-f2c> returns an invalid C handle.

NOTE

This function does not return an error value. Consequently, the result of calling it before MPI_Init <#mpi-init> or after MPI_Finalize <#mpi-finalize> is undefined.

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2003-2026, The Open MPI Community