---
name: "MPI_Win_c2f"
section: "3"
platform: "linux"
package: "openmpi"
version: "5.0.11-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/MPI_Win_c2f"
---

# MPI\_Win\_c2f(3)

*MPI\_Comm\_f2c*, *MPI\_Comm\_c2f*, *MPI\_File\_f2c*, *MPI\_File\_c2f*, *MPI\_Info\_f2c*, *MPI\_Info\_c2f*, *MPI\_Message\_f2c*, *MPI\_Message\_c2f*, *MPI\_Op\_f2c*, *MPI\_Op\_c2f*, *MPI\_Request\_f2c*, *MPI\_Request\_c2f*, *MPI\_Type\_f2c*, *MPI\_Type\_c2f*, *MPI\_Win\_f2c*, *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* returns a valid C handle to that same communicator; if *comm* = MPI\_COMM\_NULL (Fortran value), then *MPI\_Comm\_f2c* returns a null C handle; if *comm* is an invalid Fortran handle, then *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* or after *MPI\_Finalize* is undefined.

## COPYRIGHT

2003-2026, The Open MPI Community