Code:

const

UnixDateDelta = 25569; { 1970-01-01T00:00:00,0 }

SecPerMin = 60;

SecPerHour = SecPerMin * 60;

SecPerDay = SecPerHour * 24;

MinDayFraction = 1 / (24 * 60);

{Convert Unix time to TDatetime}

function UnixTimeToDateTime(AUnixTime: DWord; ABias: Integer): TDateTime;

begin

Result := UnixDateDelta + (AUnixTime div SecPerDay) { Days }

+ ((AUnixTime mod SecPerDay) / SecPerDay) { Seconds }

- ABias * MinDayFraction { Bias to UTC in minutes };

end;

{Convert Unix time to String with locale settings}

function UnixTimeToStr(AUnixTime: DWord; ABias: Integer): string;

begin

Result := FormatDateTime('ddddd hh:nn:ss', UnixTimeToDateTime(AUnixTime, ABias));

end;

{Convert TDateTime to Unix time}

function DateTimeToUnixTime(ADateTime: TDateTime; ABias: Integer): DWord;

begin

Result := Trunc((ADateTime - UnixDateDelta) * SecPerDay) + ABias * SecPerMin;

end;

procedure TForm1.Button4Click(Sender: TObject);

begin

Label1.Caption := UnixTimeToStr(977347109, -60);

end;