The author is obviously trolling with the article (not the OP, the article the OP linked).

But ... I had assumed for all these years that time_t was an unsigned type; I typically use it or unsigned long for timestamps. I actually learned something when I went to disprove the article. Hmm. I never used time_t for historical dates, I've always used other types -- so I've never needed negative values. With a 32-bit unsigned integer, the value would run until 2106. And with 64 bits it runs until ... um, much later

Does anyone use negative time_t values?

Oh, and doesn't DOS/FAT/MSWindows/NTFS use 32-bit numbers starting from 1900, but with 2-seconds per tick? That would make it roll over in 2037 if I'm right -- but I'm not sure ....