SlackwareThis Forum is for the discussion of Slackware Linux.
Welcome to LinuxQuestions.org, a friendly and active Linux Community.
You are currently viewing LQ as a guest. By joining our community you will have the ability to post topics, receive our newsletter, use the advanced search, subscribe to threads and access many other special features. Registration is quick, simple and absolutely free. Join our community today!
Note that registered members see fewer ads, and ContentLink is completely disabled once you log in.
If you have any problems with the registration process or your account login, please contact us. If you need to reset your password, click here.
Having a problem logging in? Please visit this page to clear all LQ-related cookies.
Introduction to Linux - A Hands on Guide
This guide was created as an overview of the Linux Operating System, geared toward new users as an exploration tour and getting started guide, with exercises at the end of each chapter.
For more advanced trainees it can be a desktop reference, and a collection of the base knowledge needed to proceed with system and network administration. This book contains many real life examples derived from the author's experience as a Linux system and network administrator, trainer and consultant. They hope these examples will help you to get a better understanding of the Linux system and that you feel encouraged to try out things on your own.
Click Here to receive this Complete Guide absolutely free.
Ufff, dual booting, the first thing that occurred to Patrick, was responsible. Or rather my not choosing the proper timezone in Windows together with the fact that Windows was set to adjust time based on internet sources. My timezone (Windows) was Central Time (-6.00) when in fact mine is -3.00. That's why my clock led by exactly 3 hours!
Location: Northeastern Michigan, where Carhartt is a Designer Label
Distribution: Slackware 32- & 64-bit Stable
The three-character abbreviations are the time zone; in the conterminous US, there is Eastern, Central, Mountain and Pacific, there is Standard time and Daylight time and there is Time: thus, EST, CST, MST and PST during "normal" months and EDT, CDT, MDT and PDT during "daylight savings" months (Alaska and Hawaii are far west of those zones, they abbreviate as AKST and HAST).
The ART is simply the country code (AR) and Time (seems like Argentine only has one time zone?).
"Wide" countries have multiple time zone and the three- or more character codes are just a way to keep things on track. The basic rule is that every 10 degrees east or west of Greenwich is one hour; that's not political, it's physical. The way the time zone are carved out, though, is political (look at a world time zone map and you'll see that -- no straight lines there). This one is kind of cute: http://www.timeanddate.com/time/map/. There are places on the planet where some time zones are in half-hours (gotta wonder about that).
And all along, Windows had your clock screwed up. Oh, well.
Argentina has two different times since some years now. And since about the same time we do not have daylight time. But should not the fact that we use standard time be reflected in 'ART', and be 'ARST'?
A remark that comes to my mind is, why so few man pages speak about the format of the command output? Example, 'date'.
Try the opposite settings than suggested by eloi in post #11.
The Linux thing
I don’t bother too much with the time settings in BIOS.
When I run timeconfig I choose the option „Hardware clock is set to UTC” and I set the right time zone („Europe/Warsaw” in my case though „Europe/Paris” does the same – sets the time to the Central European one). Then I use date command to set the right date and time. Finally I run hwclock --systohc command to write the right time to BIOS.
In /etc/rc.d/rc.local_shutdown I set the same command:
# save time
In /etc/rc.d/rc.local I set the commands:
# adjust time
/sbin/hwclock --adjust ; /sbin/hwclock --hctosys
When I need to change the time I use the mentioned date and hwclock --systohc commands.
I don’t bother with --utc and --localtime switches because hwclock recognizes the valid settings using /etc/hardwareclock file.
The Windows thing
When you use dual booting with Linux and Windows the latter system spoils the time at the turn from the summer to winter and from the winter to summer (Widows makes the correction already made by Linux). To disable that find in Windows the time settings and switch off the correction for the summer/winter time.
The time thing
To check the right time in the different time zones use the following site:
I'm not quite done with this problem it seems, and for the moment I made this: Went to windows and disabled the network thing, leaving daylight disabled too. Now I'm waiting to have stable symptoms before I take any measure.
As to your advices, I'll try them later, not now as I have said. The saving of system time to the hw clock at shutdown, I think the OS does it by default, but I'll have an eye on it.
"What’s missing in the man date in your opinion?": Maybe I should know the meaning of ART but could not the manual say a word about the way the output specifies the country code and daylight condition?
The date command reports the time zone (“CET” in the following example).
Sat Mar 9 19:30:00 CET 2013
It doesn’t display country/region because different countries or regions use the same time zone – for example CET/CEST is used in France, Germany, Poland etc.
To display the time and the date in the different time zones use my script:
# time+date: displays zone name, time, and date for the given time zone
# use abbreviations such as: CET or CEST
# or coutry names such as: Poland
# or region/city names such as: Europe/Warsaw
# or GMT offsets such as: GMT-02
if [ "$1" == "" ]
time+date: displays zone name, time, and date for the given time zone
time+date [ZONE | Country | Region/City | GMT±n] [-l | --local]
(see: /usr/share/zoneinfo directory)
CET or CEST
if [ "$2" == "-l" ] || [ "$2" == "--local" ]
NOW=`date +"%Z %H:%M %m-%d"`
TIME=`TZ="$1" date +"%Z %H:%M %m-%d"`
ART 15:30 03-09
time+date America/Buenos_Aires -l
CET 19:30 03-09
ART 15:30 03-09
(In the above example the first line displays the local time.)
Avoid time zones abbreviations because they are sometimes ambiguous and – as a result – display invalid values:
ART 18:30 03-09
To display the daylight conditions use the command:
zdump -v ART
ART Fri Dec 13 20:45:52 1901 UTC = Fri Dec 13 20:45:52 1901 ART isdst=0 gmtoff=0
ART Sat Dec 14 20:45:52 1901 UTC = Sat Dec 14 20:45:52 1901 ART isdst=0 gmtoff=0
ART Mon Jan 18 03:14:07 2038 UTC = Mon Jan 18 03:14:07 2038 ART isdst=0 gmtoff=0
ART Tue Jan 19 03:14:07 2038 UTC = Tue Jan 19 03:14:07 2038 ART isdst=0 gmtoff=0
or the command:
zdump -v America/Buenos_Aires
America/Buenos_Aires Fri Dec 13 20:45:52 1901 UTC = Fri Dec 13 16:29:04 1901 CMT isdst=0 gmtoff=-15408
America/Buenos_Aires Sat Dec 14 20:45:52 1901 UTC = Sat Dec 14 16:29:04 1901 CMT isdst=0 gmtoff=-15408
America/Buenos_Aires Sun Mar 16 01:59:59 2008 UTC = Sat Mar 15 23:59:59 2008 ARST isdst=1 gmtoff=-7200
America/Buenos_Aires Sun Mar 16 02:00:00 2008 UTC = Sat Mar 15 23:00:00 2008 ART isdst=0 gmtoff=-10800
America/Buenos_Aires Sun Oct 19 02:59:59 2008 UTC = Sat Oct 18 23:59:59 2008 ART isdst=0 gmtoff=-10800
America/Buenos_Aires Sun Oct 19 03:00:00 2008 UTC = Sun Oct 19 01:00:00 2008 ARST isdst=1 gmtoff=-7200
America/Buenos_Aires Sun Mar 15 01:59:59 2009 UTC = Sat Mar 14 23:59:59 2009 ARST isdst=1 gmtoff=-7200
America/Buenos_Aires Sun Mar 15 02:00:00 2009 UTC = Sat Mar 14 23:00:00 2009 ART isdst=0 gmtoff=-10800
America/Buenos_Aires Mon Jan 18 03:14:07 2038 UTC = Mon Jan 18 00:14:07 2038 ART isdst=0 gmtoff=-10800
America/Buenos_Aires Tue Jan 19 03:14:07 2038 UTC = Tue Jan 19 00:14:07 2038 ART isdst=0 gmtoff=-10800
As to your advices, I'll try them later, not now as I have said.
There is a tide in the affairs of men.
Which, taken at the flood, leads on to fortune;
Omitted, all the voyage of their life
Is bound in shallows and in miseries.
On such a full sea are we now afloat,
And we must take the current when it serves,
Or lose our ventures.
The saving of system time to the hw clock at shutdown, I think the OS does it by default, but I'll have an eye on it.
You’re right: /etc/rc.d/rc.0 and /etc/rc.d/rc.6 do that. My settings are very old. Probably in those old times the system didn’t save the system time to the hardware clock so I had to do that. Or maybe I just doubled the default settings in /etc/rc.d/rc.local_shutdown unconsciously.