A QUICKY GUIDE TO DOS

                             by

                         Gary Nored




Why Should I Learn DOS?


     It has been often said that you can do a lot with a 
computer without ever learning anything about DOS. And that 
is certainly true. But you can work more efficiently and 
safely if you do know a little bit about DOS. DOS is really 
not hard to use -- it's just hard to get started with 
because it's so cryptic. This article is intended to help 
you get started. 


What Is DOS?


     DOS is really two things. One is a computer program 
which operates 'behind' or 'underneath' other programs and 
which gives your computer its personality. DOS takes care of 
details like writing files, interpreting what is going on at 
the keyboard, and putting things on the screen. You need 
never worry about that part of DOS because it does this part 
of its work invisibly. 


     The other part of DOS is more like a library of 
programs or a toolkit of computer tricks. As you work on 
different jobs, DOS saves your work in 'files' on the disks. 
there can be many files on a disk, but DOS helps you keep 
track of them all. One of the tools in the DOS toolkit is a 
program that can show you a list of your files at any time. 
Other tools help you make copies of your work, remove old 
work from your disks, and assign new or different names to 
your jobs. 


     Some of your DOS tools remain in the computer's memory, 
available for use all the time. The DIR command (which means 
"show me a list of all the files on my disk"), the DEL 
command ("delete this file from the disk"), the COPY ("make 
a copy of this file"), and the REN command ("rename this 
file") are examples of the tools, or commands, that always 
reside in the computer's memory.


     Most DOS tools, however, are stored as files on a disk. 
You have to have a copy of them on a disk somewhere in the 
computer before you can use them.


USING DOS


     To use DOS you speak to it using little DOS sentences. 
The rules, or "syntax" for making a DOS sentence are pretty 
straightforward. The first rule says that you must always 
separate each word in the sentence with a space. That's a 
lot like writing in any other language. The second rule says 
that you must type each word in the proper order. The final 
rule says to finish each DOS sentence by pressing the 
<return> key.


     ONE-WORD SENTENCES. The simplest DOS sentence has just 
one word, a verb. In DOS, verbs are called commands. We'll 
use "commands" from now on to help you get used to the terms 
you may later encounter in your DOS manual. 

     Here's an example of a one-word DOS sentence: 


     DIR <return>


If the bottom line on your computer screen said A> when you 
typed this sentence, DOS would give you a DIRectory, or list  
of the files on the disk located in the disk drive with the 
name A:.


     TWO-WORD SENTENCES. Some DOS sentences have two words. 
The second word in a DOS sentence is the object of the 
command. The object can be anything the command understands. 
For example, we can ask for a directory of the files located 
on any drive in the computer. To see the files on drive B: 
you would type


     DIR B: <return>.


     Just as many languages have different endings for 
different words, DOS has different endings for some of its 
commands. The endings, called switches, usually improve the 
way the command works in certain situations. For example:


     DIR/P <return>


will make very long lists of files stop at the end of each 
screen so that you have time to read them all. Another:


     DIR/W <return>


will put the list into five columns so that you see more file 
names on the screen. You can even combine endings; DIR/W/P 
would put the list into five columns AND stop the listing at 
each page. The switches are different for each command. To 
use them you have to learn them -- just like any other 
language. Fortunately, you probably won't need to use very 
many of them. 


     THREE-WORD SENTENCES. One of the most common DOS 
sentences is also the longest possible one. It has 
three words which tell the computer to COPY something. It's 
also the most complex because you have to tell DOS (1) what 
you want to copy, (2) where you want to put it, and (3) what 
you want to call the copy. 


     Let's say you've written a letter and saved it to a 
disk using the file name PAYME. The disk is currently in the 
A: drive and you want to copy it to a disk in the B: drive. 
You want to use the same name for the copy as for the 
original. The last line on your computer says A>. Here's the 
command:


     COPY PAYME B: <return>


     In this sentence the first word tells the computer to 
copy something; the second word tells the computer what to 
copy; the third word tells the computer where to put the 
copy and what to call it. If you wanted the copy to have a 
different name, for example IPAIDYOU, you would put the new 
name right after the B: like this:


     COPY PAYME B:IPAIDYOU <return>.


     Notice that there is NO SPACE between the B: and the 
new file name. That's because you must use different 
punctuation to separate parts of filenames and their 
locations. Specifically, use a colon to separate the drive 
name (usually A:, B:, or C:) from the first part of the file 
name. Use a period to separate the first part of the file 
name from the last part.

     Here's an example. If the above file was on a disk in 
the A: drive, its complete name would be A:IPAIDYOU. If your 
file had a last name (called the "extension" in DOS jargon) 
of DOC, its complete name would be A:IPAIDYOU.DOC. If the 
same file was on a disk in the B: drive, its full name would 
be B:IPAIDYOU.DOC.

    Since this is the hardest part about learning to use 
DOS, here's the information in a table.



PUNCTUATION MARK                   FUNCTION
________________         __________________________________

     Space               Separates words in a DOS sentence.


     /                   Tells DOS that you intend to use a 
                              switch


     :                   Separates the drive letter from the
                              file name


     .                   Separates the file's first name 
                              from its last name
________________         __________________________________



     Let's look at the first copy sentence again.


     COPY PAYME B: <return>


What will be the name of the new file on drive B:? The 
answer -- PAYME. Why? Because whenever you don't tell DOS 
exactly what you want it to do, it just uses the last thing 
it heard. In this case the last file name DOS heard was 
PAYME. So DOS used the name PAYME for the new file name when 
it made the copy. 


     Lets look at another example. Suppose you wanted to 
copy a file located on the B: drive named PAYME onto a disk 
in the A: drive. The last line on your screen says A>. The 
following sentence will do the job:


     COPY B:PAYME <return>.


What will happen here? Well, DOS will make a copy of PAYME 
on the disk located in your A: drive. Why? DOS put the copy 
on the A: drive because DOS was looking at the A: drive 
(that's what the A> on your screen really means) when it 
started. DOS named the copy PAYME because that's the last 
file name DOS knew anything about. In fact, anytime you 
leave things out of a DOS sentence, DOS just fills in the 
blanks. Here's how DOS fills in the missing information in 
the sentence above:


     COPY B:PAYME A:PAYME <return>.


     Why not just type in the whole sentence? Of course, you 
could, but the less you type, the fewer errors you're likely 
to make, right? Letting the computer do it will ensure that 
the file gets copied under the name you really want.


WILDCARDS


     If DOS allowed only statements like the ones we've been 
studying, it would take a lot of time and typing to copy all 
the files on a disk to a backup disk. But DOS has two other 
tools that help with big jobs like that. 


     The first tool is the "*." Anytime you use an asterisk 
you tell DOS to match any character or characters it sees 
for the operation. Put another way, any time you use a "*" 
you're telling DOS that you don't care how many characters 
are in the file name, or even how the name is spelled. So:


     COPY A:*.* B: <return>


will copy all the files on the A: drive to the B: drive. 
Why? Because you've just told DOS to copy all the files, no 
matter how their names are spelled, from the A: drive to the 
B: drive.


     The instruction:


     COPY A:*.COM B: <return>


would copy all the files with the last name COM to the B: 
drive. The instruction will ignore the spelling of all the 
first names. 


     You will probably use the following command often:


     COPY A:*.* B: <return>


The *.* command copies all the files from one disk to 
another. Great for backing up all your files at one time. 


     There is another wildcard, the "?" that's similar, 
except that it matches only one character at a time. Use one 
question mark for each character in the filename you expect 
to change. For example:


     COPY A:FILE? B: <return>


would copy any file on A: with a name in which the first 
four letters were FILE and the fifth letter was any 
character. Using the command above would copy all of the 
files listed below to the B: drive in one step.


     FILE0
     FILE1
     FILE2
     FILE3
     FILE4
     FILE5
     FILE6
     FILE7
     FILE8
     FILE9


     By using the "?" wildcard, you've done exactly the same 
amount of work as if you'd typed the following list of 
commands:

     COPY FILE0 B:
     COPY FILE1 B:
     COPY FILE2 B:
     COPY FILE3 B:
     COPY FILE4 B:
     COPY FILE5 B:
     COPY FILE6 B:
     COPY FILE7 B:
     COPY FILE8 B:
     COPY FILE9 B:

Just imagine how many mistakes you might have made doing the 
job that way. 


     You can also use wildcards to good advantage when 
removing unwanted files from a disk. For example:


     DEL *.BAK <return>


will delete all files with the last name BAK, no matter what 
their first name. BAK is a popular last name for backup 
files created automatically by your computer, and sometimes 
you might want to take some of them off to make more room on 
a disk.


     Try the wildcards with the DIR command for practice. 
Typing:


     DIR *.COM <return>


will give you a list of all the files on your disk with the 
last name COM.


FORMAT


     One powerful DOS command everyone has to learn how to 
use is the FORMAT command. You must FORMAT each new disk you 
buy to create data spaces on a disk in patterns your 
particular computer can recognize. The FORMAT command 
creates these data spaces. If you have two floppy disks put 
DOS in the A: drive and a new disk in the B: drive. Make 
sure that DOS is "logged" (looking at the A: drive by typing 
A: <return> before you start. Then type:


     FORMAT B: <return>


to prepare the disk.


     Let's say that you've just bought the latest version of 
a word processor called "Purple Prose." You would like to be 
able to put your Purple Prose disk into the A: drive, turn on the 
computer, and start writing -- without having to flip a 
bunch of disks around. What you need is a copy of Purple 
Prose on a "system" disk. A system disk contains hidden 
files the computer needs to put itself together when you 
first turn it on.


     To format a system disk, use the command: 


     FORMAT B:/S


Format will create a disk containing the hidden files it 
needs for its own "system" purposes.


     FORMAT is the only truly dangerous command in DOS and 
it's most dangerous to hard-disk owners. Always be careful 
to specify the drive containing the new disk. If you don't, 
and you keep answering "yes" to the formatting questions, 
DOS may just do what you say and format itself out of 
existence!


CONCLUSION


     Now that you know a little more about DOS, try using 
it. First make a backup copy of a disk you have a lot of 
data on. Use the COPY *.* instruction to make the backup. 
Then try making selective directories of your files. Try 
making selective group copies using the wildcards. Try the 
delete command using different wildcards (be sure to use a 
copy of your disk to practice this command -- DEL *.* has 
caused a lot of DOS owners a lot of grief)! 


     Try reading about the REName and other commands in your 
DOS manual and using them. Most of all, just PLAY with these 
instructions and find out what they do. Sometime, someday, 
one of them is going to rescue you from a situation you 
could never have fixed on your own before. And THAT is a 
great feeling!


                          THE END