DOS - My First
Batch File
You have heard a lot about DOS and
batch files but you just can't figure out how to create one yourself?
Learn here how to create your first
DOS patch program in a few easy steps.
2 Create
a DOS batch - "hello.bat"
3 Execute
a DOS batch - "hello.bat"
1
General
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DOS batch files are written in
plain text. Any text editor that can
store plain text can be used to create a new DOS batch file. DOS batch files use the file
extension .bat or .cmd. In our simple example we will
use Notepad to create a batch file right on the desktop. The Notepad program is available
on all Windows platforms. |
2
Create a DOS batch -
"hello.bat"
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Description |
Use Notepad to create a new file
called hello.bat on your
desktop. Add the code shown below to
the file and save it. This can be done step by step as
follows: |
Do |
·
In the Start menu
click: Programs - Accessories -
Notepad |
|
The Notepad program starts up
showing an empty document with the title: "Untitled - Notepad" |
Do |
·
In the Notepad menu
click: File - Save As |
|
The Save As dialog shows up |
Do |
·
In the Save As
dialog use the Save in drop down
box to select: Desktop ·
In the File name field overwrite the file
name by typing: hello.bat ·
Click: Save |
|
The Save As dialog will
close. Notepad shows an empty document
with the title: "hello.bat - Notepad".
A new icon with the name hello.bat appears on the Desktop. |
Do |
·
Type or copy/paste
the following code into notepad: |
Code |
@echo Hello world. @pause |
Do |
·
In the Notepad menu
choose: File - Save |
Congrats |
Done! Your fist DOS batch file is ready to run. |
3
Execute a DOS batch
- "hello.bat"
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|
Do |
·
Minimize all windows
and locate the icon called hello.bat
on your desktop. ·
Double click the hello.bat icon |
|
A new window will open showing the
following message: |
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Hello world. Press any key to continue . . . |
Do |
·
Press any key, e.g.
Space |
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The window will close. |
Congrats |
You just executed your first DOS
batch. |
4
Summary
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When double clicking hello.bat on
the desktop the file was passed to the DOS command processor. Independent from the executed batch file
the command processor will always open a new window. This window will close when the command
processor finished executing the batch file. The command processor executes
the commands listed in the batch file line by line. Commands in the batch file can instruct the
command processor to interact with the user, i.e. to show some text output in
the window or to wait for keyboard input. If not instructed differently
the command processor echoes each command from the batch to the window before
executing it. This can be useful for
testing and debugging but is usually annoying in the final version of the
batch file and because of this omitted in the example by having the ‘@' sign
in front of each line. |
Inside Hello.bat |
The first line instructs the
command processor to show the text: "Hello World." The second line instructs the
command processor to pause till the user hits a key on the keyboard. After pressing a key the batch
file finishes and the command processor will close the window. |
Lesson learned |
The simple example teaches three
features of the command processor. ·
The echo command displays text on the
screen. ·
The pause command causes the command
processor to pause until the user hits a key on the keyboard. ·
The ‘@' sign at the beginning of a line
prevents the command processor to echo the line on the screen while
executing. |
Tip |
To turn off the echoing of
commands for the whole batch file use the "@echo off" command as first command in the batch file. The hello.bat example can be rewritten as
follows in order to avoid an ‘@'
in front of each line: |
Code |
@echo off echo Hello world. pause |
5
How to continue from
here
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Now you have your first DOS
batch running and you may want to know what all you can use it for. A whole group of predefined DOS
commands is available with your operating system that can be used to enhance
this simple example and make a useful application out of it. To list all predefined dos
commands open a command console and type help. This can be done as follows: |
Do |
·
In the Start menu
click: Run |
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The Run dialog box opens |
Do |
·
In the Open edit box type: cmd.exe |
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The command console opens
reporting the windows version. A
blinking cursor shows up. |
Do |
·
Enter: help and hit the Enter
key |
|
A list of predefined DOS
commands with a brief description shows up.
Followed by the blinking curser waiting for more input. |
Do |
·
Pick any dos command
from the list. Type help and the DOS command to get more
information about it's usage. I.e.
type: help echo and hit Enter to get the details about the echo command |
Example |
C:\>help echo Displays messages, or turns
command-echoing on or off.
ECHO [ON | OFF]
ECHO [message] Type ECHO without parameters to
display the current echo setting. C:\> |
Lesson learned |
There is a whole list of
predefined DOS commands available. Those
DOS commands can be combined in a batch file in order to build a useful DOS
batch application. |