Did it print the year "100" or "19100"?
Hmmmm. After thinking about that for a minute I realize that math and aesthetics do not mix and that one single format for years makes a lot of computers not get confused. I rest my case. :(
printf("year: %s%d", rand()%2 ? "19" : "'", year);
Where the real problem is the upstream year value.(Or, if the log is expected to print 95 instead of 1995, then 100 is what we expect it to print for 2000, but the difference still matters -- 19100 in that case would show that something was seriously wrong.)
We fixed it a few days later, but it didn’t cause much trouble so it was largely forgotten.