vince@tc.fluke.COM (Craig Johnson) (12/01/88)
I have gotten tired of my 7300 keeping inaccurate time. A long time ago there was a program floating around which caused a daemon to start up which applied periodic adjustments to the system time. Was this ever posted here or was it a commercial product? If it is public domain could someone send me a copy or repost it? Does anyone know if this program updates the real time clock hardware, or only the system time kept in software? If this doesn't show up, there may be a way to easily improve your system's timekeeping anyway. It turns out that the system time is only set (read from the real time clock hardware) on boot-up. This is performed by "date -" being executed by root. From that time forward until the next reboot, the system time is based on a different clock source. I haven't looked at the hardware manual yet to figure out if it is the microprocessor clock or yet another clock (for time slice interrupts?), but it is definitely different from what the RTC hardware sees. If your Unix-pc has been up for a while, login as someone other than root and type, $ date -; date "Date -" cannot change your system time since you are not root, but it will print out the time found in the real time clock hardware. If the hardware clock and the system clock (software) were keeping the same time you would expect the second date command to spit out a time which follows the first time by a couple of seconds. On my 7300 the time is considerably different, and it is the RTC value which tracks reality closest. So here is the proposal: If I can't get the time correction daemon program I'm looking for, I propose to add a line to my crontab which will execute "date -" once a day, thereby setting the system time to the RTC value daily. This should make life more tolerable for me, perhaps it will help others also. I'm making the assumption here that crontab is executed by smgr or cron which has root privileges. We'll see if this is good enough. If not, I will look into writing my own time correction daemon. I'll let you know if it comes to that. Craig V. Johnson ...!fluke!vince John Fluke Mfg. Co. Everett, WA
clb@loci.UUCP (Charles Brunow) (12/02/88)
In article <6163@fluke.COM>, vince@tc.fluke.COM (Craig Johnson) writes: > I have gotten tired of my 7300 keeping inaccurate time. > > A long time ago there was a program floating around which caused a > daemon to start up which applied periodic adjustments to the system > time. Was this ever posted here or was it a commercial product? If > it is public domain could someone send me a copy or repost it? Does > anyone know if this program updates the real time clock hardware, or > only the system time kept in software? > You should have received the file "fixRTC.c" by now. I used to have it in a shar with instructions but, ... I'm curious about the errors y'all are having; my system runs about 30 sec/wk fast and varies with season. I've been keeping up with the rate for a good while now and my guess is that temp is the variable. Anyway, fixRTC keeps my system running within about 5 secs of the WWV times if I check and diddle it monthly. Who else has some data? -- -- #_\_@\\/\_@\\/\_@\ Charles Brunow Loci Products # /--u// --u// --o/ clb@loci.UUCP POB 833846-131 # _ __ _ _ __ __ __ ..!uunet!texbell!loci!clb Richardson, Texas 75083
cdold@starfish.Convergent.COM (Clarence Dold) (12/02/88)
From article <6163@fluke.COM>, by vince@tc.fluke.COM (Craig Johnson): > I have gotten tired of my 7300 keeping inaccurate time. [ ... ] > If your Unix-pc has been up for a while, login as someone other than > root and type, > > $ date -; date > The newer Convergent Systems do have such a line in the crontab: 0 4 * * * (echo "setting the system date\nfrom: \c"; date; date -; echo "to: \c"; date) >/dev/console -- Clarence A Dold - cdold@starfish.Convergent.COM (408) 434-2083 ...pyramid!ctnews!professo!dold MailStop 18-011 P.O.Box 6685, San Jose, CA 95150-6685 -- Clarence A Dold - cdold@starfish.Convergent.COM (408) 434-2083 ...pyramid!ctnews!professo!dold MailStop 18-011 P.O.Box 6685, San Jose, CA 95150-6685
thad@cup.portal.com (Thad P Floryan) (12/06/88)
True; the UNIXpc, when left up 30+ days at a time, does tend to advance its clock more than is desirable. Several months ago I modified the "utc" program that was posted to, perhaps, comp.sources.misc, to correct the problem. I run the corrected version every Sunday morning; it calls the US Naval Observatry in Washington, DC and adjusts BOTH the time-of-day-clock AND the battery-backed real-time-clock. I'll be posting this shortly to unix-pc.sources; been working the proverbial 25 hrs/day, 7 days/week recently and need to first catch up on the 50+ newsgroups to which I subsribe. Thad Floryan [thad@cup.portal.com (OR) ...!sun!portal!cup.portal.com!thad]