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Sometimes we care about things that happened in the 19th century (birthdates, for example.)

Yes, but nothing in a UNIX system happened in the 19th century. Non-UNIX systems lacking "time_t" have done quite well dealing with times; I don't see any need to use "time_t" for every kind of timestamp any application could possibly want.

Sorry, but I disagree. UNIX provides some very nice date/time manipulation routines, which know about time zones and daylight time, months of the year, leap years, and various other ugly stuff that people don't like to reimplement. An application that has to store a date has a strong incentive to use the existing routines rather than to invent a new format. It would be VERY NICE if the UNIX routines were useful for more than just timestamps on the local system. It is not necessary that time_t be used for this, as long as there is some standard representation that can do it. ctime might be one, ISO time might be one, or struct tm might be one, or it might be something new. I had to reinvent this wheel, and I swiped code from ctime like crazy. I wound up choosing ISO time (char string) as my standard format. My resulting code is highly unportable, because it knows about time_t and two different conventions for time zone, and it has all the daylight rules built into it. Mark