msc_wers@jhunix.UUCP (04/06/87)
Help! My computer (an AT&T 3b2) doesn't know that we've changed the weekend for the Standard/Daylight time. How can I convince it we are now in EDT and not EST? I'd appreciate e-mail responses. -Ed Scheinerman (msc_wers@jhunix)
mwh@jhunix.UUCP (04/06/87)
In article <4646@jhunix.UUCP> msc_wers@jhunix.UUCP (Edward R Scheinerman) writes: >My computer (an AT&T 3b2) >doesn't know that we've changed the weekend >for the Standard/Daylight time. How can I convince it >we are now in EDT and not EST? > Since this applies to all vanilla System V implementations, I'll respond here. SysV sets timezone by looking at the TZ environment variable. The format of the variable is <3letter timezone name><hours from Greenwich><3 letter timezone name> The first timezone stands for "standard" time, the second for "daylight savings" time. So the normal commands in /etc/profile to set TZ should be TZ=EST5EDT export TZ The operating system only knows about 1 time format - seconds from 1969 in the GMT zone. Various library routines (see ctime(3)), NOT the kernel, adjust the zone by the value of TZ to give you the corrected time (e.g., the output of the date command). These routines assume that from the last weekend in April to the last in October each year that the time should be adjusted, and the second timezone in the TZ variable be used as a label. Unfortunately, the feds changed this recently, creating a slight problem with wiring in DST changes. To get around this, one must set TZ to the following now TZ=EDT4 export TZ and change it back to normal on the last weekend in April, as follows TZ=EST5EDT export TZ These commands should be put in /etc/profile, or something that is sourced from that script, such as /etc/TIMEZONE. mwh
mjb@hoosier.UUCP (04/07/87)
In article <4647@jhunix.UUCP> mwh@jhunix.UUCP (Michael Hrybyk) writes: >to the following now > >TZ=EDT4 >export TZ > >and change it back to normal on the last weekend in April, as follows > >These commands should be put in /etc/profile, or something that is >sourced from that script, such as /etc/TIMEZONE. > >mwh Actually, you don't have to change it back until october, as long as it is before the daylight rules end. Also, on our HP-UX systems, which are derived from SYS V, the files /etc/{rc, profile, csh.login, inittab} all have explicit refs to the TZ var. What a pain! mjb. --------------- Disclaimer? Why? What's wrong wid DAT claimer? mjb%hoosier@cs.utah.edu
peter@citcom.UUCP (04/07/87)
In article <4647@jhunix.UUCP>, mwh@jhunix.UUCP (Michael Hrybyk) writes: > One must set TZ to the following now > TZ=EDT4 > and change it back to normal on the last weekend in April, as follows > These commands should be put in /etc/profile, or something that is > sourced from that script, such as /etc/TIMEZONE. Thanks for the help; this worked out real well for me. We did not have the option of changing GMT locally. Let me add that on our SCO Xenix, you have to edit /etc/default/login in addition to /etc/rc, /etc/profile, /etc/login and all users login scripts. -- Peter Klosky, Citcom Systems (materiel de telecommunications) seismo!vrdxhq!baskin!citcom!peter
guy@gorodish.UUCP (04/08/87)
>Also, on our HP-UX systems, I believe that some HP-UX systems, at least, handle DST correctly - they load the rules from a file - so you can fix it that way. >which are derived from SYS V, the files /etc/{rc, profile, csh.login, >inittab} all have explicit refs to the TZ var. The "/etc/TIMEZONE" file is a relatively recent addition to S5; it wasn't in the VAX version of S5R2, which is what a lot of S5R2-derived systems were based on.
galen@pdp.cs.OHIOU.EDU (Douglas Wade Needham) (04/13/87)
Even better yet, let's write our congressmen and tell them what we think of their ideas concerning time changes. -- douglas wade needham #include <disclamer.h> I personally think DST is a communist plot to confuse the free world 8) 8) (I don't like it at all!!! - a disgruntled Amatuer Astronomer...) -- ----S----N----A----R----K----S----&----B----O----O----J----U----M----S---- Douglas Wade Needham (614)593-1567 (work) or (614)597-5969 (Home) Electrical Engineering Dept., Ohio University, Athens, Ohio 45701 UUCP: ...!cbatt!oucs!galen ** Smart Mailers: galen@pdp.cs.OHIOU.EDU
authorplaceholder@gorgo.UUCP.UUCP (04/16/87)
Some wrote:
>I personally think DST is a communist plot to confuse the free world
This could be true, but...
Getting back to the actual topic at hand.... System V release 3.1 includes
a set of patches that *fix* the timezone problem for the 3B2 computers. If your
machine is on maintenance, you may be able to obtain this patch free for other
releases (2.0, 2.0.X, 2.1, 3.0) by calling 1-800-922-0354 with your machine
serial number in hand. If your machine is not on maintenance, you can upgrade
to release 3.1 or make the support service a one-time-charge (which might be
as expensive as the upgrade). If all else fails write to me or call me and
I will pursue a solution for you further myself.
Hope that this helps.
Steve Blasingame (AT&T Oklahoma City) 405-948-5560
bsteve@gorgo.att.com
ihnp4!gorgo!bsteve