Dumb question #1: what applications use the offset from GMT of local time? (That is, why do we want the offset in the tm structure in the first place?) I've run across it in networking applications, such as mail, netnews, and transactions. They get char string date/time info from some other place (possibly around the world) and have to understand it. Dumb question #2: if there's a way to turn tm structures into time_t values, does the ability to do something like offset = time_of_interest - convert_tm_to_gmt(localtime(time_of_interest)); (possibly followed by offset = -offset; depending on what sex you think the offset should be) obviate the need for a GMT offset element in the tm structure? Partly. At the higher levels, what I really want to do is things like this: Convert gmtime char string to localtime char string Convert localtime char string to gmtime char string Compare two times to see which is older. Compare two times to see if one is more than X older or newer than the other Add or subtract X hours (minutes, days, seconds, years) from a time. Also, a long isn't enough to handle the times of interest. Sometimes we need subsecond precision. Sometimes we care about things that happened in the 19th century (birthdates, for example.) Part of me wonders if a floating type could be used for time_t. Nobody wants subsecond precision on a birthdate, although they might want it for times very close to "now". I guess what I really want is a floating point where zero means "now", but that doesn't exactly work out unless you throw in a fixed reference point. Mark