Diff of getopt

• The added line is THIS COLOR.
• The deleted line is THIS COLOR.
• Go to getopt.

[[C]] > [[getopt]]

- コマンドラインオプションの処理
--  https://www.mm2d.net/main/prog/c/getopt-01.html
--  https://www.mm2d.net/main/prog/c/getopt-02.html getopt
--  https://www.mm2d.net/main/prog/c/getopt-03.html getopt_long