Batch File Scripting Techniques

In this section you will find a collection of scripting techniques and best practices for batch files.

Most of these techniques apply to either "DOS batch" (also related to as "real DOS" batch or "true DOS" batch), or "NT batch", only in rare cases to both. If you want to use "true DOS" batch techniques in Windows NT 4 or later (2000, XP, Server 2003, Vista) you may have to invoke these batch files with COMMAND /C.
Check the "classification" for a batch technique by hovering your mouse pointer over the information icon at the left of the titles before asking why a batch file doesn't work in your environment.

• Data & Environment Variables
• Working with Devices
• Working with Files
• Working with Folders
• Internet
• Inventory
• Miscellaneous
• Network
• Printing
• Processes & Services
• Program Flow
• Working with the Registry
• Samples Collections
• Security
• Time & Date
• UNIX Ports
• User Interaction

Data & Environment Variables

1. Arrays
   Who said the batch language doesn't know arrays? Think again.
2. Comments
   How to add comments to your batch files.
3. Delayed variable expansion and FOR loops
   Setting variables inside FOR loops or inside other code blocks.
4. Escape characters
   How to tell CMD.EXE not to interpret certain characters.
5. Integer Math
   Use the SET command for simple integer math.
6. Parameters
   How to parse command line parameters (or arguments).
7. Random Numbers
   Sample batch files to generate random numbers.
8. Strings:
   
   • String Substitution
     Use the SET command to find and replace a substring in a string.
   • Substrings
     Use the SET command to extract a substring at a fixed position in a string.
9. Verify if Variables are Defined
   With a chapter on "hidden" (dynamic) variables.

Back to the top of this page . . .

Working with Devices

1. Devices
   Check if a "file" name is a device name.
2. DEVCON
   Manage devices and drivers, a command line utility alternative to the Device Manager.

Back to the top of this page . . .

Working with Files

1. Read files
   
   • FOR /F overview
     Read lines from a file or from another command's output.
   • FOR /F's tokens and delims
     Explanation of "tokens=... delims=..." with hands-on examples.
2. Write files
   
   • Redirection overview
     Send screen output to a file or to the next command.
   • Redirection and streams explained
     Standard error, standard output and console "streams" explained.
3. Open Files
   Use the START command to open a file with its associated program.
4. Read INI Files
   Sample batch file to read INI files.
5. Temporary Files
   Some notes on temporary files as used by my batch samples.

Back to the top of this page . . .

Working with Folders

1. FOR /D and FOR /R
   Use the FOR command's /D and /R switches to handle sets of folders instead of files.
2. RD
   RD /Q /S works like a DELTREE replacement.

Back to the top of this page . . .

Internet

1. Prompt to download
   Check if utilities are available, and prompt to download if they aren't.
2. E-mail
   Send e-mails from a command line or batch file.
3. FTP
   Automate FTP uploads and downloads.

Back to the top of this page . . .

Inventory

1. WMIC
   WMI queries from the command line.
2. MSINFO32.EXE is one of Windows' native inventory tools.
   It is usually located in the folder "C:\Program Files\Common Files\Microsoft Shared\MSInfo".
   Without command line arguments it will run in GUI mode.
   Type MSInfo32 /? for a list of available command line arguments.
3. DXDIAG.EXE is Windows' native DirectX diagnostic tool.
   It is usually located in the "%windir%\System32" directory.
   Without command line arguments it will run in GUI mode.
   Type DXDiag /? for a list of available command line arguments.

Back to the top of this page . . .

Miscellaneous

1. AUTOEXEC.BAT
2. Debug your batch files
   For those rare cases when your batch file doesn't do what it was expected to...
3. Undocumented NT commands
   Hard to find documentation for some commands available in Windows NT and later.
4. UNIX ports
   "Ports" of UNIX commands to Windows NT 4+.
5. Useless tips?
   Strange or unexpected behaviour of some DOS commands, and how to use it to your advantage.

Back to the top of this page . . .

Network

1. DS Tools
   Directory Services Tools, command line utilities to query and manage Active Directory.
2. E-mail
   Send e-mails from a command line or batch file.
3. RAS
   Manage dial-up connections.
4. Terminal Server
   Command reference for some Terminal Server-only commands.

Back to the top of this page . . .

Printing

1. Print files
   Find the print command for a specific file type, and print the file.
2. Use your installed applications' command line switches to print files from the command line.
3. Control printers
   Manage printers and print queues on the command line.
4. Command line DDE
   Control programs that can act as DDE servers.
5. Use GetPrint.vbs to list (non-DDE) Print and PrintTo commands for all registered file types.

Back to the top of this page . . .

Program Flow

1. Conditional execution
2. Errorlevels
   Use error levels (or actually return codes) to control the flow of a batch file.

Back to the top of this page . . .

Processes & Services

1. Processes
   Manage processes.
2. Shutdown
   Shutdown, reboot and logoff commands for "all" DOS, Windows and OS/2 versions, in batch as well as other languages.
3. Command line DDE
   Control programs that can act as DDE servers.

Back to the top of this page . . .

Working with the Registry

1. REGEDIT
   Use REGEDIT non-interactively.
2. REG
   Query the registry with REG Query.

Back to the top of this page . . .

Samples Collections

1. Browse the MS-DOS examples
   An old collection of batch file scripting techniques, most of them for MS-DOS only.
2. Clever Tips and Tricks
   Several tips sent to me by visitors of this site.
3. How To ...
   An old collection of batch file scripting techniques, most of them for MS-DOS only.
   The page will be opened in a new window because the frameset is incompatible with the DHTML menu and the stylesheet switcher.
4. Poor man's admin tools
   A collection of scripts that can be used to replace resource kit utilities or commands no longer available in recent Windows versions.
5. Scripts for Windows Administrators
   Batch files, KiXtart, Perl, Rexx and VBScript.
6. Solutions found on alt.msdos.batch
   Several clever scripting solutions from the alt.msdos.batch and alt.msdos.batch.nt newsgroups.
   Most of these are from the previous millennium, but still hold their own.
7. Third Party Batch Files
   Complete scripts sent to me by visitors of this site.
8. Useful NT commands for Windows Administrators
   Powerful "one-liners" for the command prompt.
9. UNIX Ports
   Some scripts to compensate for the missing (UNIX) commands in DOS & Windows.

Back to the top of this page . . .

Security

1. Security Configuration with SeCEdit and MMC
   Set permissions, inheritance and ownership on files, folders and registry keys.

Back to the top of this page . . .

Time & Date

1. DATE and TIME in MS-DOS
   The basic syntax and some strange ways of using the DATE and TIME commands in COMMAND.COM.
2. DATE and TIME in NT
   The basic syntax and some advanced samples of date math in CMD.EXE.

Back to the top of this page . . .

UNIX Ports

1. UNIX Ports
   Some scripts to compensate for the missing (UNIX) commands in DOS & Windows.

Back to the top of this page . . .

User Interaction

1. User Input
   How to make your batch files prompt for user input.
2. User Output
   
   • Error Messages
     Display error messages in the local system language.
   • Popup Messages
     Generate popup messages with your batch files.

Back to the top of this page . . .