Given that some people want a facility in some system library to manipulate dates prior to 1902, why not: 1) Leave the UNIX time manipulation routines alone, and use them only for what they were intended - dealing with time stamps for system events. 2) Provide a general-purpose time value manipulation package for the benefit of applications that have to deal with arbitrary dates and times. In fact, you may even be able to write the latter package in some language available on lots of machines (C, Fortran, whatever), and decouple it from the system entirely.