DOS COMMANDS FOR BEGINNERS
Most people will not need to know or use these commands
at all, but they are well worth knowing understanding and practising. Most
the command will also work through and within windows many 95/98 programs.
DOS stands for disk operating system. DOS is the software
program, which controls the input and output of your computer.
Over the years DOS has been produced in a variety of versions.
New commands and capabilities have been added and different versions for
a variety of machines have evolved. Presently at the time of updating this
(1997) we are up to Dos a version of Dos 7 which is provided as part of
and inside Windows 95/98 system.
Never erase the following files, if you do the computer
will most likely not start these are called:
MSDOS.SYS
IO.SYS
COMMAND.COM
These are the heart of your computer and it will not run
properly, if at all, without them. Never erase the DOS directory as this
is where the operating system is. The computer will not run properly without
Dos.
In the case of Windows 95/98 then the operating system
dos files are found in the actual windows and windows\command directories.
You should not erase these directories unless you know what you are doing.
GETTING THE FEEL - POWER ON
There are TWO ways to use DOS.
1.) Directly at the prompt using what is termed a COMMAND
LINE. This is the detailed method we will look at in a paragraph or so.
2.) A second way is to use a DOS SHELL or MENU to manage
files and other data.
If a:\> is on the screen at power up or if you are asked
to insert a system disk, then it's possible that you might not have a hard
disk. Or that your hard disk might not yet have an operating system written
onto it.
If there is a hard drive, but no operating system, then
simply insert the first Dos or operating system disk into the floppy drive
or any supplied boot disk and then turn on the computer, it should go into
the set-up procedure. Follow the on screen instructions, it will or should,
tell you what to do.
A Dos Prompt is the
C:\>
that you should see on your screen. However shutting down
to dos from windows 95/98 would show
C:\>WINDOWS
The following examples are best practised at the DOS prompt
A:\>
or
C:\>
You might wish to print this file and then practice the
examples with your computer.
Now let's begin the basic commands tutorial:
You can CHANGE the default drive simply. Put in a formatted
floppy disk. Then let's try switching drives. Type one of the following
three lines then hit enter
a:
b:
c:
type in either Capitals or lower case it makes no difference,
as either will work.
First practice getting this symbol below (two dots one
above the other usually found located next to the letter L key)
:
on your screen, you will use it quite a lot. Use one of
the shift keys and the key next to the letter L to get this : on screen.
You MUST get into the habit of pressing ENTER or RETURN
after you type in any command. If you do not press ENTER or RETURN the
command will not work. The RETURN and ENTER keys do the same thing. ENTER
is the last bottom key to your right of the keyboard. RETURN is the large
key located above the shift key to your right of the keyboard.
What you are doing is switching between your drives, go
back and forth a few times. Switching drives is very important since dos
pays attention to the drive of which letter is displayed! Next let's try
some other simple DOS commands.
try typing VER then press enter key
try typing DIR then press enter key
try typing MEM then press enter key
In the above examples, you first asked DOS to tell you
what version of DOS you are using. Next you requested to be shown the Directory
contents. Then you requested to see your memory configuration.
Now try these . . .
dir/w press enter /w - means "wide across the screen"
dir means show directory contents
dir/p press enter - show directory and Pause the screen
a page at a time
dir/w/p press enter - wide and pause directory display
dir/o press enter - give directory with files listed in
alphabetical order.
dir a: press enter - list a: drive contents with a floppy
in the drive of course.
dir b: press enter - list b: drive contents
dir/w/o/p press enter - all the above commands together
(directory, wide, order, paused)
help press enter - show dos help files
help /? press enter - shows windows dos help file commands
For Dos 6.0 & 6.2 users you can work your way about
a help menu by using the CURSOR (Arrow) Keys. Move the flashing blinker
to the command you want to read about and simply press ENTER. To escape
or quit help, press ALT then ENTER next move the highlight bar at the top
left of the screen, to where it says exit and then press ENTER.
SUB DIRECTORIES
Floppy disks have a relatively limited space to store
files they are limited in comparison to the space on a hard drive. To find
a necessary file name on a floppy, just use the DIR or directory command.
However, on a hard disk things get a little out of hand with hundreds of
files all listed on the same screen.
Dos solution to this is obtained by adding sub directories
and path names to manage the location and organization of files.
A path is nothing more than a "trail" or "direction post"
which helps DOS find a particular file out of the hundreds which may be
located on a hard drive.
This path name is facilitated by the use of multiple directories
(called sub directories) on a single disk. In this fashion you sort files
into groups in a specific place on the drive. By the way, a sub directory
is itself a small file and does occupy space on the disk.
You could compare a hard or floppy disk to a shop. The
shop might sell toys, books and clothes. Similar items go in the rightly
allocated area of the shop.
A disk also has the capacity for many separate areas in
which to place files. DOS refers to these with a main central directory
(root directory) and sub directories branching below it. You can create
a sub directory named TEXT which contains all your word processing documents.
Computer utilities could be in a sub directory called UTIL, and so on.
On the screen, a listing of any sub directory might show
the first two entries mysteriously named
.
..
(single dot and double dot).
The first dot is a name for the sub directory itself.
The double dot is a name for the parent (higher) directory one level up.
MAKE DIRECTORY
MD MAKES A DIRECTORY. e.g. MD GAMES
CD\ brings you to the root (main directory) no matter
where you are.
cd\dos (change to the dos directory)
cd\windows\system (change to sub directory within a directory)
windows system.
If you were already in a directory and need to change
to a sub directory within, then you would not use the \ slash you would
instead use just the space key.
EXAMPLE if you were in windows directory you would have
this on your screen
c:\>windows>
To now change to the command sub directory you would type
the CD command
CD.. To get back to the main directory
CD\ ALSO gets back to A route directory
CD CHANGES DIRECTORY e.g. CD GAME or CD\GAME
dir SHOWS A DIRECTORY CONTENTS
dir/w DIRECTORY WIDE ACROSS THE SCREEN
dir/p DIRECTORY PAUSE A PAGE AT A TIME
dir/w/p WIDE AND PAUSE DIRECTORY
dir/o DIRECTORY ORDER ALPHABETIC
dir *.exe DIRECTORY OF FILES ENDING .EXE
dir *.bat DIRECTORY OF FILES ENDING .BAT
dir *.COM DIRECTORY OF FILES ENDING .COM
dir t*.* DIRECTORY OF FILES BEGINNING WITH THE LETTER
T
dir ta*.* DIRECTORY OF FILES STARTING TA
dir /s DIRECTORY SHOW TRUE FULL SIZE AND SUB DIRS
dir /s *.txt USE THIS FROM C:\PROMPT AND EVERY FILE ON
YOUR HARD DRIVE ENDING TXT WILL BE DISPLAYED.
FILE NAMES & EXTENSIONS
When you see the following
*.*
This means select or show all files (example: copy move
delete *.*)
When you see the following
*.
This is typed by pressing the shift key and the number
8 key at the top row (above I an U) of the keyboard and the full stop.
It means select or show only any file ending For example *.bat means file
ending .bat
When looking at an individual file, look at the extension,
the bit after the dot. This will give you a clue what sort of file it is.
For example
Autoexec.bat is a bat file bat short for batch.
Config.sys is a sys file short for system file
DELTREE RD or RMDIR
RD removes an empty sub directory (it cannot remove a
sub directory loaded with files as a safety measure use the DEL *.* command
to first clear a sub directory.)
The root (main) directory cannot be removed. But the files
could be deleted. Should you do this you will lose your systems main operating
files The computer would not work.
Deltree removes a directory sub directories and all files
within them. Example: deltree Temp Available with Dos 6.0 and above
Del *.* removes files but not directory or sub
directories.
If you try to deltree a directory from the dos prompt
and it does not complete the job, then the problem is more likely to be
that you have one or more hidden files in there. You would now need to
change their attributes to then delete them.
You cannot see a hidden file from the dos prompt. You
would need to use windows file manager or a dosshell type program, such
as Norton commander or Xtree gold. However, you would still first have
to tell such a program to enable or display the hidden files on screen.
The default is do not show them as they are usually of importance to a
program or your operating system.
FILE ATTRIBUTES
You need to learn about attrib - short for file attributes,
this is four different styles of file types. Archive. System. Hidden. Read
Only. A files attributes can be changed. You can not write to a read only
file unless you first change the attributes of that file to archive. You
can not see o hidden file from the dos prompt. It's best to leave this
till you become more experienced but you can see Dos Help for further details
if you really need to.
Dos commands
del c:\games - WOULD DELETE ANY FILES IN THE DIRECTORY
BUT NOT THE DIRECTORY NOR ANY SUB DIRECTORIES
copy *.* - COPIES FILES FROM ONE PLACE TO ANOTHER e.g.
copy a:*.* c:\games
copy *.* b:/v - COPY AND VERIFY A GOOD COPY.
diskcopy a: a: - COPY THE CONTENTS OF ONE DISK TO ANOTHER
move *.* - MOVES FILES FROM ONE PLACE TO ANOTHER AVAILABLE
ON DOS 6.0 6.2 UPOVER
xcopy - COPIES FILES AND DIRECTORIES FROM ONE PLACE TO
ANOTHER
label - WOULD ALLOW A DISK TO BE NAMED.
Chkdsk - CHECKS A DISK
Scandisk - CHECK A DISK (ONLY IF RUNNING DOS 6 OR 6.2
OR UPOVER)
Mem - SHOWS YOUR MEMORY USAGE CONSUMPTION and WHAT IS
FREE ETC
mem/c |more - SHOWS AN ADVANCED DISPLAY OF MEMORY USAGE
memmaker - AUTOMATIC MEMORY CONFIGURATION FROM DOS 6.0
AND 6.2 UPOVER
dblspace - COMPRESSES DATA DOUBLING HARD DRIVE SPACE ONLY
DOS 6.0 6.2 UPOVER
cls - CLEARS THE SCREEN
date - SHOWS AND ALLOWS THE DATE TO BE CHANGED
time - SHOWS AND ALLOWS THE TIME TO BE CHANGED
ren old.txt new.txt - RENAMES THE FILE OLD.TXT TO NEW.TXT
vol - SHOW THE VOLUME LABEL OF A DISK
comp - COMPARES TWO FILES
diskcomp a: b: - COMPARES TWO DISKS
undelete - IF YOU MAKE A MISTAKE AND ERASE A FILE YOU
WILL BE ASKED TO INSERT THE FIRST LETTER OF THE
NAME OF THAT FILE TO RECOVER IT.
The often used *.* means ANY FILE NAME and ANY extension
regardless of length. But does not include Sub directories.
The often used *. Means any file name ending with the
extension e.g. dir*.bat
USING DOS FORMAT
format - WOULD NOT FORMAT A DISK
format a: - TO FORMAT DRIVE A:
format b: - TO FORMAT DRIVE B:
format c: - TO FORMAT A HARD DRIVE
format a: /u - FORMATS WITHOUT SAVING A MIRROR IMAGE OF
WHAT WAS PREVIOUSLY ON A DISK THIS
LEAVES THE TOTAL DISK SPACE COMPLETELY EMPTY.
format a: /q - SUPPLIES A QUICK FORMAT
format a: /u /q - AS ABOVE TWO COMMANDS TOGETHER
format a: /f:720k FORMATS A DOUBLE DENSITY 720K DISK
format b: /f:360k -FORMATS A DOUBLE DENSITY 360K DISK
(5.25 size)
format a: /s - MAKES A BOOTABLE SYSTEM DISK
UNDELETE
If you should accidentally erase a file that you need,
then try typing UNDELETE from the dos prompt. This would retrieve it, but
you will be asked to type in the first letter of the file name, to be able
to continue and retrieve it. Example: !utoexec
If you have erased files and since this, placed something
else onto the hard drive, the new files usually over write the space previously
used, in this case you may not be able to retrieve lost files.
USING CHKDSK OR SCANDISK
chkdsk b: - check b: floppy, all files
chkdsk c:\*.* - check for contiguity of files in root
of c: drive Scandisk is more advanced than chkdsk and available with Dos
6.2 up over
scandisk c:\ - scans and checks c:\
scandisk a:\ - scans and checks a:\
USEFUL KEYS
In most applications you will use these are the most often
used keys.
F1 THROUGH TO F12 (F1 Usually brings a help file)
ALT
TAB (Key with two arrows on it to the left of the keyboard)
ESC
ENTER RETURN (both the same function)
F10 In most applications will access a menu (DOSSHELL
WINDOWS)
CTRL ALT DEL (Reboot system) Touch the three keys in succession.
CURSOR KEYS (arrow keys)
: a colon
