Most time libraries - especially the stdlib ones - are broken in various subtle ways. ISO time formatting is neat, but only works for past events. Your approac

Most time libraries - especially the stdlib ones - are broken in various subtle ways. ISO time formatting is neat, but only works for past events. Your approach is usually going to be sufficient-ish for timestamping past events - which is most applications. But try to build a calendar, and you'll quickly notice that it simply doesn't work that way.