The value returned by time is the number of seconds since epoch (often 0:00, Jan 1st, 1970 GMT). The number of seconds since some point in time doesn't change depending on where you happen to be located, so it's not affected by $ENV{TZ}.

Convert the value return by time into a local time (e.g. using localtime) to see the change.

Note: I think you need to call POSIX's tzset for the change to be noticed by localtime.

Note: I think changing $ENV{TZ} *after* perl starts doesn't work properly in Windows. It works fine if you change it *before* perl starts.

use POSIX qw( tzset );

print localtime(time) . " in $ENV{TZ}\n";

$ENV{TZ} = 'GMT-8';
tzset();

print localtime(time) . " in $ENV{TZ}\n";
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Mon Dec  3 00:22:29 2007 in America/New_York
Mon Dec  3 13:22:29 2007 in GMT-8
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