Saturday, April 25, 2020
Small Company Y2k Report Essays - Calendars, Software Bugs, COBOL
Small Company Y2k Report Table of Contents 1. Introduction 2. Testing Procedure 3. Hardware and Software Compliance 4. Summary 1. Introduction Year 2000, Y2K or Millennium Bug! What is it? It is a problem resulting from the common programming practice of using only two-digits to store the year in software. The practice dates back to the 1950's when computers began to be used for business purposes. Using two digits for dates is benign and causes no harm so long as the next year is a larger number than the current year. For example software applications that use dates have no problem with the sequence of 95,96,97,98 and 99. However, when the century ends, the year 2000 will be stored as 00. Calculations or decisions, based on dates or time periods, can go seriously wrong. How is it fixed? Inregard to personal and small business computers, the problem is three fold. Firstly, the computer hardware must report the current date correctly. Many computers, especially early Pentiums, 486, 386 and 286 based machines, will on the 1st January 2000 Revert back to 1 April 1980 or some other date. Thus creating a potential problem until the correct date is re-entered - provided of course that the computer can be set manually to a date beyond 311299. Calculation of Leap Year dates may also be incorrect on some computers. Secondly, the computer software must carry out the correct calculations based on a four-digit year (e.g. 1999 or 2000 etc) rather than just using the last two digits. The supplier or manufacturer of the software should be approached to ascertain the compliance of their code, or their schedule to have it corrected and distributed. Thirdly, your data must be in the correct format - namely year described as a four-digit number. If your dates have been entered as described above (that is 15th Feb 1955 entered as 150255), then you have a data conversion to be carried out. Testing Procedure To determine if Windows NT 4.0 ,Win95 and would roll to the appropriate date, the control panel applet DATE&TIME(d&t) was used to change the dates. The machines d&t were set to the day before each date outlined in the memo. The machine date was changed to a control time of 11:59:45 PM in each case. The machine date was then allowed to roll to the date in question. The machine d&t was then reset to the previous date and control time. This time the machine was rebooted while the time was rolling to the date in question. In each case, after the time rolled, the date was checked to find the correct date. WinNT and Win95 Explorer was then opened and a file in the 'c:\winnt' and 'c:\windows' directory was changed to check whether or not a saved file corresponded with the correct date. The data from these tests is defined in the following table. 'Data & Time Tested' column are the Control values found in the memo. Both 'Post Test Date' columns are the dates found in each instance after the date rolled from the 'Date&Time Tested' column to the date in question. The 'Post Explorer check' was tested to see if the machine reported the right time. 'Post modification dates' are file dates after the file was saved to check the corresponding date. In each test, no problems with the d&t were encountered. Results: The testing actually caused several different things to happen to the OS. Whenever I rolled the date forward, The following directories changed the date associated with them: Windows NT Test C:\Winnt, C:\Winnt\System32, C:\Winnt\Fonts, C:\Temp. Windows 95 Test C:\Windows, C:\Windows\System, C:\Windows\Fonts, C:\Temp This seemed strange because the machine time stamp wouldn't roll back when the time was changed backwards, but this isn't part of the test procedure. When the time actually changes the date will roll forward and stay. It won't roll backwards. I don't know if this affects the testing but it would be totally impossible to rebuild the machine each time the test was run. This would take many hours to do and it probably won't affect the data anyway. Before I started testing, I looked on the Internet to see what Microsoft said about WinNT 4.0, Win95 and the y2k problem. On this site, there are links to all Microsoft Products. For WinNT 4.0, there were 4
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