Input

 tzlen

    Length of the tzname buffer.

 utc

    Binary timestamp.

    Output

 tzname

    Character string long enough to hold the time zone label.

 tdf

    Longword with differential in seconds east or west of GMT.

 isdst

    Integer with a value of zero if standard time is in effect or a
    value of 1 if daylight savings time is in effect.