Before Windows was created, the most common operating system that ran on IBM PC compatibles was DOS. DOS stands for Disk Operating System
and was what you would use if you had started your computer much like
you do today with Windows. The difference was that DOS was not a
graphical operating system but rather purely textual. That meant in
order to run programs or manipulate the operating system you had to
manually type in commands. When Windows was first created it was
actually a graphical user interface that was created in order to make
using the DOS operating system easier for a novice user. As time went
on and newer versions of Windows were developed DOS was finally phased
out with Windows ME. Though the newer operating systems do not run on
DOS, they do have a something called the command prompt, which has a
similar appearance to DOS. In this tutorial we will cover the basic
commands and usage of the command prompt so that you feel comfortable
in using this resource.
Using the Command Prompt or Dos Window
When people refer to the command prompt
they may we refer to it in different ways. They may refer to it as a
shell, console window, a command prompt, a cmd prompt, or even dos. In
order to enter the command prompt you need to run a program that is
dependent on your operating system. Below we list the programs that you
need to run to enter a command prompt based on the version of Windows
you are running.
|Windows 3.1,.3.11, 95, 98, ME
||This program when run will open up a command prompt window providing a DOS shell.
|Windows NT, 2000, XP, 2003
||This program will provide the native command prompt. What we call the command prompt.
|Windows NT, 2000, XP, 2003
||This program will open up a emulated DOS shell for backwards compatibility. Only use if you must.
To run these programs and start a command prompt you would do the following steps:
Step 1: Click on the Start Menu
Step 2: Click on the Run option
Step 3: Type the appropriate command in the Open: field. For example if we are using Windows XP we would type cmd.exe.
Step 4: Click on the OK button
After following these steps you will be presented with a window that look similar to Figure 1 below.
Figure 1. Windows Command Prompt
The command prompt is
simply a window that by default displays the current directory, or in
windows term a folder, that you are in and has a blinking cursor ready
for you to type your commands. For example in Figure 1 above you can
see that it says C:\WINDOWS>. The C:\WINDOWS> is the prompt and
it tells me that I am currently in the c:\windows directory. If I was
in the directory c:\program files\directory the prompt would instead
look like this: C:\PROGRAM FILES\DIRECTORY>.
To use the command prompt
you would type in the commands and instructions you want and then press
enter. In the next section we will discuss some useful commands and how
to see all available built in commands for the command prompt.
The command.com or cmd.exe
programs have built in commands that are very useful. Below I have
outlined some of the more important commands and further instruction on
how to find information on all the available commands.
command – This command will list all the commands built into the
command prompt. If you would like further information about a
particular command you can type help commandname. For example help cd
will give you more detailed information on a command. For all commands
you can also type the command name followed by a /? to see help on the
command. For example, cd /?
The Exit command – This command will close the command prompt. Simply type exit and press enter and the command prompt will close.
command – This command allows you to change your current directory or
see what directory you are currently in. To use the CD command you
would type cd directoryname and press enter. This
would then change the directory you are currently in to the one
specified. When using the cd command you must remember how paths work
in Windows. A path to a file is always the root directory, which is
symbolized by the \ symbol, followed by the
directories underneath it. For example the file notepad.exe which is
located in c:\windows\system32 would have a path as follows
\windows\system32\notepad.exe. If you want to change to a directory
that is currently in your current directory you do not need the full
path, but can just type cd directoryname and press
enter. For example if you are in a directory called c:\test, and there
were three directories in that the test directory called A, B, and C,
you could just type cd a and press enter. You would
then be in the c:\test\a. If on the other hand you wanted to change
your directory to the c:\windows\system32 directory, you would have to
type cd \windows\system and press enter.
command – This command will list the files and directories contained in
your current directory, if used without an argument, or the directory
you specify as an argument. To use the command you would just type dir
and press enter and you will see a listing of the current files in the
directory you are in, including information about their file sizes,
date and time they were last written to. The command will also show how
much space the files in the directory are using and the total amount of
free disk space available on the current hard drive. If I typed dir \test I would see the contents of the c:\test directory as shown in Figure 2 below.
Figure 2. DIR of c:\test
If you examine the
screen above you will see a listing of the directory. The first 2
columns are the date and time of the last write to that file. Followed
by whether or not the particular entry is a directory or a file, then
the size of the file, and finally the name of the file. You may have
noticed that there are two directories named . and .., which have special meaning in operating systems. The . stands for the current directory and the .. stands for the previous directory in the path. In the example above, .. stands for c:\windows.
Also note for many commands you can use the * symbol which stands for wildcard. With this in mind, typing dir *.txt will only list those files that end with .txt.
The Copy command – This command allows you to copy files from one location to another. To use this command you would type
copy filetocopy copiedfile. For example if you have the file c:\test\test.txt and would like to copy it to c:\windows\test.txt you would type
copy c:\test\test.txt c:\windows\test.txt
and press enter. If the copy is successful it will tell you so and give
you back the prompt. If you are copying within the same directory you
do not have to use the path. Here are some examples and what they would
|copy test.txt test.bak
||Copies the test.txt file to a new file called test.bak in the same directory
|copy test.txt \windows
||Copies the test.txt file to the \windows directory.
|copy * \windows
||Copies all the files in the current directory to the \windows directory.
The Move command – This command allows you to move a file from one location to another. Examples are below:
|move test.txt test.bak
||Moves the test.txt file to a new file renaming it to test.bak in the same directory.
|move test.txt \windows
||Moves the test.txt file to the \windows directory.
|move * \windows
||Moves all the files in the current directory to the \windows directory.
At this point you should use the help command to learn about the other available commands.
Redirectors are an
important part to using the command prompt as they allow you to
manipulate how the output or input of a program is displayed or used.
Redirectors are used by appending them to the end of a command followed
by what you are redirecting to. For example: dir > dir.txt. There are four redirectors that are used in a command prompt and they are discussed below:
||This redirector will take the output of a program and
store it in a file. If the file exists, it will be overwritten. If it
does not exist it will create a new file. For example the command dir > dir.txt
will take the output of the dir command and place it in the dir.txt
file. If dir.txt exists, it will overwrite it, otherwise it will create
||This redirector will take the output of a program and store it in a
file. If the file exists, the data will be appended to the current data
in the file rather than overwriting it. If it does not exist it will
create a new file. For example the command dir >> dir.txt
will take the output of the dir command and appends it to the existing
data in the dir.txt file if the file exists. If dir.txt does not exist,
it will create the file first.
||This redirector will take the input for a program from a specified
file. For example the date command expects input from a user. So if we
had the command date < date.txt, it would take the input for the date program from the information contained in the date.txt file.
||This redirector is called a pipe. It will take the output of a program and pipe it into another program. For example dir | sort would take the output of the dir command and use it as input to the sort command.
Batch files are files that
have an extension ending in .bat. They are simply scripts that contain
command prompt commands that will be executed in the order they are
listed. To create a batch file, just make a file that ends in .bat,
such as test.bat, and inside the file have the commands you would like.
Each command should be on its own line and in the order you would like
them to execute.
Below is example batch
file. It has no real use but will give you an example of how a batch
files works. This test batch file contains the following lines of text:
If I was to run the test.bat file I created I would have output that looks like the following:
Figure 3: Example of a batch file running.
As you can see from
the figure above, my batch file executed each command in my batch file
in the sequence they were written in the batch file.
If a program is created for express
purpose of running within a command prompt, or console window, that
program is called a console program. These are programs that are not
graphical and can only be run properly from within a command prompt
Below is a list of sites that contain console programs that may be useful to you:
There are many more sites that have tools available. Just do a Google search on windows console programs.
The command prompt can be a very
powerful and versatile tool for a computer user. Hopefully this brief
introduction into the command prompt will enable you to use your
computer more efficiently.