Re: Timezone offset differences

On Wed, Jan 17, 2001 at 01:58:14PM -0600, Andrei Zmievski wrote: > On Wed, 17 Jan 2001, Jim Winstead wrote: > > i didn't check how date('Z') is defined (do you add it to local time to get > > UTC or subtract it?) but it may be that systems where struct tm has a > > tm_gmtoff member and systems that use the timezone global may > > define it different ways. > > Well, I am in Central timezone so I'd expect my offset to be -21600 (-6 > hours). So, the formula should be UTC + offset. > > > they should be made consistent, and the date() documentation updated to > > tell exactly which way we've made it consistent. :) > > And making it consistent would just involve reversing the sign on > tm_gmtoff member? I just wonder if the sign of tm_gmtoff is consistent > between platforms. according to the examples i can find in the single unix spec, i'd expect timezone to be positive for US/Central time. http://www.opengroup.org/onlinepubs/007908799/xsh/tzset.html tm_gmtoff appears to be defined the opposite way. http://www.netppl.fi/~pp/glibc21/libc_20.html#SEC406 i'd say pick one, and document it. jim