Create a zero-filled binary file.

bin-file-maker.py

#! /usr/bin/python3

import argparse
import enum
import pathlib
import sys


class Units(enum.Enum):
    Kibibytes = 'KiB'
    Mebibytes = 'MiB'
    Gibibytes = 'GiB'
    Tebibytes = 'TiB'

    def __str__(self):
        return self.value

    def to_bytes(self, number):
        UNITS = {
            'KiB': 2 ** 10,
            'MiB': 2 ** 20,
            'GiB': 2 ** 30,
            'TiB': 2 ** 40
        }

        return int(float(number) * UNITS[self.value])


def _parse_arguments():
    parser = argparse.ArgumentParser(
        prog='bin-file-maker',
        description='Create a zero-filled binary file.')

    parser.add_argument('path', type=str, help='Path of the file to create.')

    parser.add_argument('size', type=float, help='Size of the file to create.')

    parser.add_argument('units', type=Units, choices=list(Units),
                        help='The unit of the size parameter.')

    values = None

    try:
        args = parser.parse_args()
        values = vars(args)

        values['path'] = pathlib.Path(values['path']).resolve()
        values['size'] = values["units"].to_bytes(values["size"])

    except SystemExit:
        return None

    return values


def main():
    args = _parse_arguments()
    if not args:
        return -1

    try:
        with open(args['path'], 'wb+') as f:
            f.seek(args['size'] - 1)
            f.write(bytearray(1))
    except Exception as ex:
        print(ex.message, file=sys.stderr)
        return -1

    return 0


if __name__ == "__main__":
    main()