function get_offset(interval: Number(gint)): Number(gint32) {
    // Gjs wrapper for g_time_zone_get_offset()

Determines the offset to UTC in effect during a particular interval of time in the time zone tz.

The offset is the number of seconds that you add to UTC time to arrive at local time for tz (ie: negative numbers for time zones west of GMT, positive numbers for east).

Since 2.26


an interval within the timezone


the number of seconds that should be added to UTC to get the local time in tz