newunit - a toy Fortran function to get a positive and an unopened unit number

Fortran's newunit feature returns a negative unit number. This causes an error, so-called "out-of-range unit number," for some compilers, NAG Fortran and NEC Fortran, in my experience.

This module provides a function that returns a positive unit number not including input_unit, output_unit, and error_unit defined in the iso_fortran_env module.

This module is created primarily for avoiding and modifying errors locally during get_getline.f90 in stdlib and close_scratch_file in VTKFortran.

usage

use the newunit module and call get_newunit_number() to get a unit number before opening a unit.

    use :: newunit
    implicit none

    integer(int32) :: unit_number

    unit_number = get_newunit_number()
    open (unit=unit_number, status="scratch")
    close (unit_number)

get the code

To get the code, execute the following commnad:

git clone https://github.com/degawa/newunit.git
cd newunit

or specifying the git repository as a dependency in fpm.toml.

[dependencies]
newunit = {git = "https://github.com/degawa/newunit.git"}