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Thread ID: 53225	2005-01-11 02:27:00	creating different dates in different partitions	bsssst (1725)	Press F1

Post ID	Timestamp	Content	User
312921	2005-01-11 22:30:00	Taking a simplistic view, it does not matter how many boot disks, partitions or instances of anything running under VM there is only one BIOS DATE which they all share. Yes, but does the O/S in partition 2 correct its date when partition 1 is fully Booted. And V V Or does only the Booted partition O/S correct its date. In a rack situation the rack sittting on the bench will not have any new date inf untill it is put back in and booted. If you have 2 bootable primary partitions, do both correct their date time data every time either is booted.??? I suppose is the correct Question???	bsssst (1725)
312922	2005-01-11 23:58:00	VM runs its own separate bios for each virtual machine you create. I believe that each bios is individually configurable, but I'll look for and post the link that alerted me to the possibilities for my issues. Cheers Billy 8-{)	Billy T (70)
312923	2005-01-12 00:15:00	OK ! Here's the link. (www.informationweek.com) I hope it works because it was sourced from my Langalist Plus subscription and not all of those links will work for non-subscribers. Read the 4th paragraph entitled "What it is" for a very quick overview. Cheers Billy 8-{)	Billy T (70)
312924	2005-01-12 01:09:00	Thinking about it, why multiboot and have two versions of the OS, one of which runs the wrong date? If its a short term thing, have that laptop and its (only) OS running at the odd date. Set it once, and leave it alone. If its a long term project, it deserves a laptop of its own. Billy, why don't you run your application from a batch file? It could prompt you to change the date-- or do it itself. It could even save the actual date as an environment variable, and set it back then the application exits.	Graham L (2)
312925	2005-01-12 01:15:00	OK ! Here's the link. (www.informationweek.com) I hope it works because it was sourced from my Langalist Plus subscription and not all of those links will work for non-subscribers. Read the 4th paragraph entitled "What it is" for a very quick overview. Cheers Billy 8-{) Yes it does work. Intersestring running 6 different O/S at once, In one box . Demo down load it says. 45 days. If nobody knows if it will do what we want, suck it and see I suppose. Choice link. Id still like an answer to: If you have 2 bootable primary partitions, do both correct their date time data every time either is booted.??? I suppose is the correct Question??? :For curiousoty's sake.	bsssst (1725)
312926	2005-01-12 01:49:00	When a PC OS is booted up, it reads the hardware clock and sets its date and time (making any modifications required for time zone, or daylight saving, or leap years). After that, the OS maintains its clock using the 18.2 Hz interrupt. It doesn't read the BIOS clock again. At midnight it changes the BIOS date. It might change the century if necessary. Or not. If you change the time and date in the OS, it will change the BIOS clock too. When I was doing real-time work, the first thing I looked for was a way to turn off the OS clock. :D (I have measured the CPU time taken by OS clocks on a range of computers from large mainframes down to Apple 2s. It's been fairly consistently around 2%). When I needed the time I would ask the hardware clock -- the BIOS one on PCs, plugin cards for minis.) Real programmes just need a programme loader, not an OS :D	Graham L (2)
312927	2005-01-12 02:32:00	When a PC OS is booted up, it reads the hardware clock and sets its date and time (making any modifications required for time zone, or daylight saving, or leap years). After that, the OS maintains its clock using the 18.2 Hz interrupt. It doesn't read the BIOS clock again. At midnight it changes the BIOS date. It might change the century if necessary. Or not. If you change the time and date in the OS, it will change the BIOS clock too. When I was doing real-time work, the first thing I looked for was a way to turn off the OS clock. :D (I have measured the CPU time taken by OS clocks on a range of computers from large mainframes down to Apple 2s. It's been fairly consistently around 2%). When I needed the time I would ask the hardware clock -- the BIOS one on PCs, plugin cards for minis.) Real programmes just need a programme loader, not an OS :D So taking the inf that the O/S commands its own date- time, and corrects Bios clock time-date. Two primary partitions shoul be adle to maintain different years and months. Altering the Bios clock each time they are started. As long as the O/S do not update the clock in the other partition what I want to do should be possible with multi booting. I had the wrong clock as the commander of system time. And the virtuall amchine softwear in theorie should also behave the same to do what billy wants. We shall see, soon. I shall run a test in multi boot with 2 primary partitions and logicall drives. Now that I have some better knoweledge, and I shall report my findings.	bsssst (1725)
312928	2005-01-12 03:21:00	When an OS is shut down, its clock stops . It does not remember the date and time it had . When it next boots, it starts from time 00:00:00 . 00 and some (random?) date . After it asks the BIOS, it knows what the BIOS knows and it carries on from there . If you (manually, or with a batch script) change the OS's day, month, and year (the DATE command, or the GUI equivalent) it will alter the BIOS registers to suit . If you shut down the "wrongdate" OS, and start the "rightdate" OS, that will start with the wrong date, because that's what the BIOS has . You can have a batch script to run the DATE command, prompting you for the proper date, or have a stored value . . . which you will need to remember to change every day or month . The DATE command requires "day month and year" . . . you might have a way to grab the proper daynumber from XP environment variables .	Graham L (2)
312929	2005-01-12 04:45:00	When an OS is shut down, its clock stops . It does not remember the date and time it had . When it next boots, it starts from time 00:00:00 . 00 and some (random?) date . After it asks the BIOS, it knows what the BIOS knows and it carries on from there . If you (manually, or with a batch script) change the OS's day, month, and year (the DATE command, or the GUI equivalent) it will alter the BIOS registers to suit . If you shut down the "wrongdate" OS, and start the "rightdate" OS, that will start with the wrong date, because that's what the BIOS has . You can have a batch script to run the DATE command, prompting you for the proper date, or have a stored value . . . which you will need to remember to change every day or month . The DATE command requires "day month and year" . . . you might have a way to grab the proper daynumber from XP environment variables . Graham, Learning more, thank you, but that brings me back to where I was . With more understanding of what really happens . == Digression So theoretically, all though I am not, and have no need to defeat it in this simple way . If the bios clock never moved forward and you shut down every day xp could be convinced it had only been installed for 1 day and the activation would never lock??? === Applications with day and month sensitive data, and activity's, such as accounting program's . These will logically be reliant on sys clock . What sort of issues may arrise if the date goes back too far . What is likely to happen to data all ready written with dates that theoretically dont yet exist, if you go back too far?? Also if this application is not opened and the sys date is found to be incorrectly set . Would correcting the date before opening the app prevent any damage, or would this occour as soon as the sys started, Theoretically??	bsssst (1725)
312930	2005-01-12 07:01:00	When a PC OS is booted up, it reads the hardware clock and sets its date and time (making any modifications required for time zone, or daylight saving, or leap years) . After that, the OS maintains its clock using the 18 . 2 Hz interrupt . It doesn't read the BIOS clock again . At midnight it changes the BIOS date . It might change the century if necessary . Or not . If you change the time and date in the OS, it will change the BIOS clock too . Graham You may be just the right person to turn your mind to this situation then: Under an MS VM installation, all of the hardware is emulated in software, including the motherboard . The bios is also emulated in the VM software so the OS (any OS) running under MS VM will only see the clock in the virtual Bios . Now, to my simple mind, the true hardware bios on the system that is running the VM cannot see the VM OS, or the VM Bios for that matter, the VM operates completely independently . I draw my conclusions re independence from the extensive info available via the link I posted earlier in this thread . To me then, it follows that in theory you can set any date you wish in the VM Bios, just as you can set any other parameter, and it should hold that date between boots . However, the logical flaw that I cannot get my head around is this: How can a virtual bios maintain a time and date if it exists only in software and ceases to operate if the VM is shutdown? Perhaps it can only look to the system clock on the host machine during boot and synchronise with that . :( Of course this does not prevent the running of a routine at boot that changes the VM clock to the preferred historical date, but then that could always be done with the host OS, which sort of completes the circle for me and my brain tries to implode . :eek: Cheers Billy 8-{)	Billy T (70)
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