FIO_UNIT - Get a unit number given a file descriptor

Description:

The Fortran unit number associated with the given file descriptor is returned.

Invocation:

CALL FIO_UNIT( FD, UNIT, STATUS )

Arguments:

FD = INTEGER (Given)

The file descriptor.

UNIT = INTEGER (Returned)

Variable to receive the unit number.

STATUS = INTEGER (Given and Returned)

The global status.