-----Original Message----- From: Chris Richards [mailto:cj_richards@hotmail.com] Sent: Tuesday, July 13, 2004 12:42 PM To: Olson, Arthur David (NIH/NCI) Subject: RE: Definition of time_t changed from signed to unsigned...

Hi,

Actually, could this be due to me using a tz.cfg database that was compiled in an environment where time_t was typedef'ed differently to the environment which loads and uses the tz.cfg?

It certainly could be due to using a signed-system-generated data file on an unsigned-time_t system. Signed time values from before 1970 are negative numbers; on an unsigned system they'll look like large positive numbers. This means that for present-day time_t values the "t < sp->ats[0]" test will be satisfied, the software will assume that it's dealing with a time predating the first transition that's recorded, and the software will apply "default" rules. "localtime.c" could be jiggered to ignore pre-1970 transitions if (1) time_t is unsigned and (2) a data file has been generated on a signed system (which can be determined by seeing if the transition times are correctly sorted from the perspective of the system on which the software is being run). Given the notes on this mailing list about the inadvisability of unsigned time_t's, such jiggering is of questionable value. --ado