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From: "hadmut at danisch dot de" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sources.redhat.com
Subject: [Bug libc/11620] New: Bad design of timezone conversions
Date: Sat, 22 May 2010 07:57:00 -0000	[thread overview]
Message-ID: <20100522075745.11620.hadmut@danisch.de> (raw)

Hi, 

glibc has pretty good functions and timezone definitions to convert
unix/universal time to local time zones. 

But unfortunately the functions are based on the assumption that you always need
only one timezone at a time, your local time. glibc supports using only a single
time zone per program run, the one set in the TZ environment variable. 

This is design of the pre-internet era. Nowadays we have to write programs like
webservers and other communication servers, which can deal with any timezone
requested and with several timezones simultaneously. 

You can experience that lack of functionality in the fact, that most programs,
that offer a customer to configure his time zones do not allow him to choose,
e.g. Europe/Berlin, but timeoffsets only, like GMT+1, GMT+2, which needs to
updated for every change between summer and wintertime or simply gives wrong
data, e.g. in a calendar. 

Would be nice and appropriate if there were functions to read in any time zone
definition given by name into a variable and to have conversion functions like
localtime and mktime to use with any time zone definition passed as a variable. 

Since these functions already exist, they just have to be modified to not use a
static variable but a given parameter, this should be easy to implement. 

regards

-- 
           Summary: Bad design of timezone conversions
           Product: glibc
           Version: unspecified
            Status: NEW
          Severity: normal
          Priority: P2
         Component: libc
        AssignedTo: drepper at redhat dot com
        ReportedBy: hadmut at danisch dot de
                CC: glibc-bugs at sources dot redhat dot com


http://sourceware.org/bugzilla/show_bug.cgi?id=11620

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             reply	other threads:[~2010-05-22  7:57 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-22  7:57 hadmut at danisch dot de [this message]
2010-05-22 13:49 ` [Bug libc/11620] " drepper at redhat dot com

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