# 18.2.321. MPI_Session_f2c

MPI_Session_c2f, MPI_Session_f2c - Translates a C session handle into a Fortran INTEGER-style session handle, or vice versa.

## 18.2.321.1. SYNTAX

### 18.2.321.1.1. C Syntax

    #include <mpi.h>

    int MPI_Session_f2c(const MPI_Fint *f_session, MPI_Session *c_session)
    int MPI_Session_c2f(const MPI_Session *c_session, MPI_Fint *f_session)

## 18.2.321.2. PARAMETERS

- `f_session`: `mpi`-style `INTEGER` MPI session object

- `c_session`: C-style MPI session object

## 18.2.321.3. DESCRIPTION

These two procedures are provided in C to convert from a Fortran session (which is an array of integers) to a C session (which is a structure), and vice versa. The conversion occurs on all the information in `session`, including that which is hidden. That is, no session information is lost in the conversion.

When using MPI_Session_f2c(), if `f_session` is a valid Fortran session, then MPI_Session_f2c() returns in `c_session` a valid C session with the same content. If `f_session` is the Fortran value of MPI_SESSION_NULL, or if `f_session` is not a valid Fortran session, then the call is erroneous.

When using MPI_Session_c2f(), the opposite conversion is applied. If `c_session` is MPI_SESSION_NULL, or if `c_session` is not a valid C session, then the call is erroneous.

## 18.2.321.4. NOTES

These functions are only available in C; they are not available in any of the Fortran MPI interfaces.