Hello, Managers. Here is my original question:
> Hello Managers. I have a problem with the timezone. If I run the
> "zdump -v GMT+1" command I get the following:
> 
> Under Tru64Unix 4.0F:
> 
>   ...... gmtoff=3600
> 
> Under TruCluster 5.1A, Tru64 Unix 5.1A, 5.1B:
> 
>  ......  gmtoff=-3600
> 
> It seems that under version 5.1x, GMT+1 is the opposite of GMT-1. Tha
> geographic area selected during installation was Europe/Madrid.
> 
> Is this an installation problem, or is this the correct operation?
> 
> Thanks in advance.
> 
> Carlos Rodriguez del Castillo <crodriguez_at_eliop.es>
> ELIOP, S.A.
> Madrid - Spain
and here is a summary of the responses:
martin.moore_at_hp.com: He explained that it is not an installation 
problem, but it is the way Tru64UNIX V5.0 and later work. Tru64 UNIX 
V5.0 (and later) comply with the POSIX.1 standard (ISO/IEC 9945-1 
ANSI/IEEE Std. 1003.1), but earlier versions do not, and this 
standard defines GMT+<n> just in the opposite way. So, GMT+1 in 
Tru64UNIX V4.0 is equal to GMT-1 in Tru64UNIX V5.0 (and later).
Tom.Peterson_at__delete-this_hp.com: He explained basically how Tru64 
UNIX V4.0 and V5.0 work with timezone. I think it is very interesting 
so I prefer inserting the complete answer better than summarizing it. 
Here is the explanation:
>    The 'zonename' argument to the zdump command is a time zone 
>    specification (by default, assumed to be the name of a time zone
>    data file relative to /etc/zoneinfo/).  Therefore, the observed
>    difference in GMT[+-]* time zone behavior is related to changes to
>    certain GMT[+-]* time zone data files under /etc/zoneinfo/.  These
>    changes are explained below.  It's also worth noting that your
>    system-wide time zone setting of "Europe/Madrid" does not affect
>    the results of zdump for the GMT[+-]* arguments you are using, as
>    zdump is using its argument instead of the system default time zone
>    setting.
> 
>    The /etc/zoneinfo/ time zone files and supporting code were updated
>    in Tru64 UNIX V5.0 to provide more robust and complete time
> transition
>    rules and support for more time zones around the world.  Also
> included
>    in this update were fixes to certain problems that existed in the
>    pre-V5.0 time zone data files and related code.
> 
>    In particular, there was a fix to the GMT[+-]* time zone data files
>    under /etc/zoneinfo/ (and the new /etc/zoneinfo/Etc/ directory) to
>    align their functionality with standard POSIX (1003.1) TZ
>    environment variable strings of the same name & sign (+/-).  That
>    is, a standard TZ environment variable setting of, say, "GMT-3"
>    used the same GMT offset as /etc/zoneinfo/GMT+3 on pre-V5.0
>    systems.  This was both confusing to customers and inconsistent
>    with the most recent zoneinfo sources available from the
>    defacto-standard public domain Olson time zone repository at
>    ftp://elsie.nci.nih.gov/pub/, from which our time zone data files
>    are derived, and which is used by several other *NIX
>    implementations.
> 
>    In Tru64 UNIX V5.0 and later releases, the GMT[+-]* time zone data
>    files are consistent with their POSIX TZ counterparts.  They are
>    also consistent with TZ behavior on other operating systems, such
>    as
> HP-UX.
>    That is, when the base time (seconds since the Epoch) is the same
>    on both HP-UX and V5.0 (and later) Tru64 UNIX systems, setting TZ
>    to,
> say,
>    "GMT-3" on either system will use the same GMT offset as it would
>    if the /etc/zoneinfo/localtime link on Tru64 UNIX V5.* (and later)
>    were set to /etc/zoneinfo/GMT-3 (or /etc/zoneinfo/Etc/GMT-3).  The
>    same result occurs when setting TZ to ":GMT-3" (note the leading
>    ':') on V5.0 (and later) Tru64 UNIX systems.  The leading ':' TZ
>    format
> causes
>    processes in that environment to use the time zone data file
> (relative
>    to /etc/zoneinfo/) whose name matches the string following the ':'.
>    See the tzset(3) reference page for more details.
> 
>    Regarding pre-V5.0 Tru64 UNIX systems, it's worth pointing out that
>    despite the difference in GMT[+-]* time zone data file
>    functionality, those systems DO handle standard POSIX-style
>    GMT[+-]* TZ environment variable strings correctly (ie: those with
>    no leading ':').
> 
>    Also note that the argument to the zdump command does not require
>    the leading ':', but rather, first assumes that the argument is the
>    name
> of
>    a time zone data file relative to /etc/zoneinfo/.  If it is not,
>    only then does zdump interpret the argument as a POSIX-style TZ
>    environment variable string.
> 
>    In summary, the TZ environment variable handling and GMT[+-]* time
> zone
>    data file names on Tru64 UNIX V5.0 (and later) are consistent with
>    conventions from the standards (POSIX and others).  They are also
>    consistent with TZ format/handling on other operating systems, such
>    as HP-UX.  These changes were made in Tru64 UNIX V5.0 in order to
>    correct the original dispartity with the standards syntax and to
>    function consistently with other systems.  The difference in output
>    that you
> are
>    seeing from zdump with GMT[+-]* arguments is reflective of these
> changes.
> 
>    As far as workarounds, someone using Tru64 UNIX V4.* could set the
>    system-wide /etc/zoneinfo/localtime link to, say,
>    /etc/zoneinfo/GMT+3
> to 
>    match the POSIX-style "GMT-3" setting on Tru64 UNIX V5.0 (and
>    later) or other systems.  Or, as long as the base times are the
>    same, one could also use a TZ environment variable setting of
>    ":GMT+3" or "GMT-3" on their Tru64 UNIX V4.* systems, though this
>    would only affect the
> current
>    environment - not the entire system.  For zdump, the solution is
>    simply to use the opposite sign for GMT[+-]* arguments between
>    Tru64 UNIX
> V4.*
>    and V5.* systems.
> 
Now I know it is not a problem of my installation, I feel relaxed. It 
is not a problem if I have to link to GMT-1 instead of GMT+1 because 
is how Tru65Unix V5.0 works.
Thanks to all. The answers have been really useful and interesting.
Best regards,
Carlos Rodriguez del Castillo <crodriguez_at_eliop.es>
ELIOP, S.A.
Madrid - Spain
Received on Fri Jul 11 2003 - 09:55:30 NZST