 The magazine of the Melbourne PC User Group A Beginner's Tale: Part 11 Ron Wilby |
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This month I have a few stories to entertain you and explain some of the mysteries of the PC.
DiskContent
For backups, my strategy is to make a full weekly backup of my hard disk, with incremental daily backups. The full backup, about 15 disks, is hidden in my brick garage, fairly safe from a house fire and burglars.
Back a few months, my PC Tools CP Backup program informed me of some disk failures. Three defunct backup disks in a period of a few weeks and they were top-brand disks from different batches, no cheapies here. I used a padded Post Bag carefully sealed for storage, and leaned it against a convenient part of the brickwork. So why did the disks fail? Temperature or humidity were a possibility. I was baffled (again) and took my troubles to the ever-helpful Doug Brooke at the New Users East SIG. There we all talked it over, and someone suggested there may be a power line embedded in the bricks. Well, that was it there is a large air-conditioner right above where the backup disks were stored. The compressor draws a hefty surge of current every time it starts and the resulting magnetic field makes about 23 kB of "bad sectors" on a disk placed near its supply cable.
Take care with your backup storage.
Incremental Problems
Recently my daily incremental backup went all wrong. As Dos 6 had been recently installed, could there be a link? I don't think so, but what really happened? The symptoms were that my regular evening incremental backup suddenly started to tell me there was 5,916 kB of files to back up, needing four disks. This would happen every day, even if I had only written one 2 kB letter to Aunt Susie because it was Sunday. Still the same 5,916 kB and four disks required.
On the phone to Central Point Software in Sydney. Someone will call you back, they said, and they did. I explained my problem and my caller promised to investigate and call me again. Hard to believe, but he did, with the news that they didn't know what was causing the problem, but as I was using Version 7.1 of PC Tools, they thought I should have the latest version. A set of disks of Version 8 will be on its way to you very soon, and we know that version works OK with DOS 6. Full marks, Central Point, for your quick response and excellent product support.
Extra Programs for DOS 6
Thanks to John Button, well-known to people attending the Retirees SIG, for a disk containing "Supplemental Programs for DOS 6."This disk is available from our bulletin board and contains around 600 kB of material, which expands to 830 kB on installation from its compressed files.
On the disk there are five groups of files. You issue the command SETUP and are given a choice of which groups you want to install.
AccessDOS is a package of MS-DOS extensions for those users who are "movement or hearing disabled" and gives them better access to computers that run DOS 6.
Keyboard Utilities includes special keyboard layouts designed to help people who type with a single hand and those who have difficulty with the standard QWERTY keyboard.
DBLBOOT.BAT creates a bootable compressed floppy disk.
Additional MS-DOS Utilities is a package of utilities from DOS 5 that aren't included in the DOS 6 upgrade.
DOS 6 Network Files is a package for those who upgraded to DOS 6 from a DOS version less than 5 and contains those network files that will work with DOS 6.
The Dogs' Tale
Once upon a time, when I didn't know DOS from DIR, I had a computer, a little knowledge, and needed to put them to some useful purpose. Charity took me to the RSPCA, offering the use of Ron and his computer, and they found me a job. It was a real dog! I had to take the handwritten forms that accompanied the sale of each
rescued dog, make records of the information, and sort the records according to the areas where the dogs were to live. This information was then to be used to write a letter to each Local Council.
Well, this was somewhat of a challenge. All I had being obsolete copies of Lotus 1-2-3 and WordStar, and I didn't know much about how to use either of them. I worked out a system that required 47 keystrokes to deal with each dog, after typing in all the details. Pretty clever, I thought, until I multiplied forty-seven by the expected 400 dogs per month and added the typing of the original data. Back to the drawing board.
Little Doggy Macros
At this point I began to learn about 1-2-3's macros, a very powerful feature. These macros are little subprograms, like batch files, to carry out several commands one after the other, without need of any action from me. Wonderful! I made 1-2-3 into a database and three keystrokes sorted each dog and combined the results into a file on disk that was to be inserted into a letter for each Local Council. Enter WordStar, which was instructed to read the above file into a form letter and print the result, which I then posted.
Rampant File Expansion
However, there was a printing problem. My printer wouldn't stop at the end of the letter, but charged ahead for several blank pages, so that I had to tell WordStar to only print page one then stop. Puzzling over the reason for the out-of-control printer for several days, I noticed another strange phenomenon. The output of the process was a letter file about 2.5 kB in size. But after a session producing 20 or 30 letters, there was a noticeable growth in the file's size, to 12 or 15 kB. Then the penny (20 cents?) dropped.
The 1-2-3 output disk file had space for 25 dogs. When this file was transferred to WordStar, 25 lines were transferred with it, even though most of those lines were usually empty. Thus, each time the form letter file was read lots of blank lines were added to the file, which consequently became bigger and bigger.
My printer, of course, had to "PRINT" these blank lines before stopping at the end of the document.
Beware of the blank lines.
I'll be back next month. See you then .......
Reprinted from the October 1993 issue of PC Update, the magazine of Melbourne PC User Group, Australia
