[[... [clock] ...]]

"The current set of places where it will try to find Olson files is:

    /usr/share/zoneinfo
    /user/share/lib/zoneinfo
    /user/lib/zoneinfo
    /user/local/etc/zoneinfo
    C:/Progra~1/cygwin/usr/local/etc/zoneinfo

That's what's done if a search for a [Tcl] time zone definition in '''$tcl_library/tzdata''' fails.

In addition, the set of hardcoded time zone names in '''::tcl::clock::LegacyTimeZone''' is recognized, as is any Posix
time zone specifier, and the special name 'localtime'."


"...'localtime' is not recommended ..."

"... if -timezone is not supplied, the order of preference is '''$env(TCL_TZ)*''';
'''$env(TZ)''';
the time zone from the [Windows] [registry]; ''':Tcl/Localtime''' (allowing a site to install
its own time zone definition in '''$tcl_library/tzdata'''),
and ''':localtime''' (the C library)"

"... this structure means that [Starpack]s for [Linux] and [Solaris]
[[and [Mac OS X] ]]
can safely omit '''$tcl_library/tzdata''' with minimal loss of functionality,
since those platforms have the Olson files always.
Windows and [HP-UX] need '''tzdata''' for full functionality, but can omit it 
if 8.4-level timezone functionality is adequate ..."




----
The list of legacy time zones handled by Tcl is:

   * adt -  Atlantic Daylight 
   * ahst -  Alaska-Hawaii Standard 
   * ast -  Atlantic Standard 
   * at -  Azores 
   * bst -  British Summer 
   * bt -  Baghdad, USSR Zone 2 
   * cadt -  Central Australian Daylight 
   * cadt - Central Australian Daylight Time
   * cadt - Central Australian Standard Time
   * cast -  Central Australian Standard 
   * cat -  Central Alaska 
   * cct -  China Coast, USSR Zone 7 
   * cct - China Coast, USSR Zone 7
   * cdt -  Central Daylight 
   * cest -  Central European Summer 
   * cet -  Central European 
   * cst -  Central Standard 
   * dst -  DST on (hour is ignored) 
   * eadt -  Eastern Australian Daylight 
   * eadt - Eastern Australian Daylight Time
   * eadt - Eastern Australian Standard Time
   * east -  Eastern Australian Standard 
   * edt -  Eastern Daylight 
   * eet -  Eastern Europe, USSR Zone 1 
   * est -  Eastern Standard 
   * fst -  French Summer 
   * fwt - French Winter 
   * gmt -  Greenwich Mean 
   * gst -  Guam Standard, USSR Zone 9 
   * gst - Guam Standard, USSR Zone 9
   * hdt -  Hawaii Daylight 
   * hst -  Hawaii Standard 
   * idle -  International Date Line East 
   * idlw -  International Date Line West 
   * ist -  Indian Standard 
   * it -  Iran 
   * jst -  Japan Standard, USSR Zone 8 
   * jt -  Java (3pm in Cronusland!) 
   * mdt -  Mountain Daylight 
   * mest - Middle European Summer 
   * met - Middle European 
   * mewt - Middle European Winter 
   * mst -  Mountain Standard 
   * ndt -  Newfoundland Daylight 
   * nft -  Newfoundland 
   * nst -  Newfoundland Standard 
   * nt -  Nome 
   * nzdt -  New Zealand Daylight 
   * nzst -  New Zealand Standard 
   * nzt -  New Zealand 
   * pdt -  Pacific Daylight 
   * pst -  Pacific Standard 
   * sst - Swedish Summer 
   * swt - Swedish Winter 
   * uct -  Universal Coordinated Time 
   * ut -  Universal (Coordinated) 
   * utc
   * wadt -  West Australian Daylight 
   * wast -  West Australian Standard 
   * wat -  West Africa 
   * wet -  Western European 
   * ydt -  Yukon Daylight 
   * yst -  Yukon Standard 
   * zp4 -  USSR Zone 3 
   * zp5 -  USSR Zone 4 
   * zp6 -  USSR Zone 5