How Time and Date are Recorded

This is a technical topic. You do not need to understand it in order to use RunDynam effectively.

This tells you how RunDynam records (on the Record of Runs files) the last modified time and date of files created. It also tells you how RunDynam restores this when it unzips files from Zip Archives, Closure/Shocks Zip Archives and Results Zip files made by RunDynam.

When you look at the time and date information for any file using the usual tools (for example, Windows Explorer, My Computer or the DOS command dir in a DOS box), the date and time you see is influenced by the Date and Time properties of your Windows operating system.

For example, when you go into daylight savings time, the time shown for any file increases by one hour. You may be able to try this as follows.

Open Explorer or My Computer and check the Date Modified column for some file.

Then right click on the time which is probably shown on the right-hand end of your Taskbar. Select Adjust Date/Time, go to the Time Zone tab. Note your Time Zone so you can restore it. Then change it by selecting some other time zone an hour or so different from yours. Click on the Apply tab. Then look back at Explorer or My Computer and click on menu item Refresh under the View menu. You will see the time of the file change by the hour or two corresponding to the different time zone you have selected.

Now return the Time Zone to what it was, and click on the Apply tab to get back to where you were. The time on the file you have been looking at should change back (after you Refresh). You can close Explorer or My Computer.

Although the file itself has not changed, what Windows tells you about the last modified date changes depending on the Date/Time settings. [Each file has what we think of as last modified absolute time and date information recorded on it. We think of the information recorded on the file as absolute information while the time reported by Windows can be thought of as DOS or Windows time. Even though the absolute time information does not change, the DOS or Windows time reported can change if the Date/Time settings change.]

For this reason, when RunDynam records the absolute time and date information on its Record of Runs files and uses this when checking if files are still the same as they were when you last ran some job. Otherwise, if you ran a job the day before you changed to daylight savings time and then asked on the day after daylight savings started, you would be told that the file times were out by an hour.

When you restore files from Zip files using the standard Windows unzipping tools such as WinZIP, they put absolute time and date information on the restored file which is different depending on the Time/Date settings. In particular the absolute time and date information put on the restored file may be different from what it was when you put the file into the zip file.

RunDynam attempts to give you the ability to restore ingredients files and results files from Zip files and to tell you (via Are Results Still Ok? under the Tasks menu) whether or not the results are the same as when you created them. If RunDynam followed the normal unzipping protocols, the unzipped files would have different absolute time information on them if the Time/Date settings have changed since you zipped them. [For example, that would happen if you zipped them before daylight savings time and then unzipped them during daylight savings time.] That would upset the checking RunDynam does when you ask Are Results Still Ok?.

Instead RunDynam attempts to restore the absolute time and date information exactly as it was when you zipped the file. The information in the files XXFLTIME.XXX in certain of the Zip files made by RunDynam is used in doing this.

URL of this topic: www.copsmodels.com/webhelp/rundynam/hc_timerec.htm

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