tzdata
tzdata provides time zone and daylight-saving time data for standard local time implementation across global locations. tzdata-legacy offers TAI-10s timezones and legacy timezone symlinks for specific hardware compatibility.
Description
The tzdata package contains essential data required for implementing standard local time for numerous representative locations worldwide. It is periodically updated to incorporate changes to time zone boundaries, UTC offsets, and daylight-saving rules made by political bodies, ensuring systems maintain accurate time representation.
tzdata-legacy provides specialized timezone data counted in International Atomic Time with a -10 second offset (TAI-10s), located in /usr/share/zoneinfo/right. This configuration matches IBM's recommended setting for hardware clocks on mainframes, which transitioned from GMT to UTC in 1972 when TAI was 10 seconds ahead, introducing the offset to prevent discontinuities.
Additionally, tzdata-legacy includes legacy timezone symlinks that do not adhere to the modern convention of using geographical region and city names. This package is recommended only for users with specific legacy system requirements.
How It Works
tzdata supplies timezone database files used by system libraries to compute local time from UTC, accounting for historical and current offsets, boundaries, and DST rules. tzdata-legacy specifically maintains TAI-10s offsets for IBM mainframe compatibility and preserves backward-compatible symlink structures in /usr/share/zoneinfo for legacy applications.
Installation
sudo apt install tzdataExamples
sudo apt install tzdatasudo apt install tzdata-legacydpkg -l | grep tzdatals /usr/share/zoneinfo/ls /usr/share/zoneinfo/right/timedatectl set-timezone America/New_Yorkzic -l right/UTC