Program for Linux terminal.
author: Piotr Knutel (piknut@linux.pl), 2023 version: 1.0 tested with: gcc 11.3.0, Ubuntu 22.04, x86_64
Usage: app [-v] [-h | --help] [--args] [-p | --param ] [--data ]
Options: --args Return the number of arguments and show a list of them --data [DMMYY] Show date DMMYY as 'day_of_week month year', e.g. 71223 as Sunday December 2023 -h, --help Show help -p, --param [VALUE] If VALUE is a number, then put the number to 'dane.txt'; if VALUE is a string, then write it on the screen; if no VALUE, then show last number from 'dane.txt'; VALUE accepts rational number (double), also negativ -v Show version