Autorun.inf, What is it?

Autorun.inf is the primary instruction file associated with the Autorun function. Autorun.inf itself is a simple text-based configuration file that tells the operating system which executable to start, which icon to use, and which additional menu commands to make available. In other words, autorun.inf tells Windows how to deal open the presentation and treat the contents of the CD.

The entire sequence is initiated when the "disk change notifcation" polling discovers a new disk in the CD or DVD ROM drive. Then, if the "Auto insert notification" feature is enabled (it is by default), Windows checks in the new disk's root directory for the existence of an "autorun.inf" file. If found, Windows then reads and follows the specific instructions this file defines. If no autorun.inf file is found, then Windows refers to the new disk by its serial number and executes the default actions associated with the (data or audio) content on the disk.

The Autorun.inf file defines the following:

	The process or application that will automatically run when a disk is inserted
	Optionally, one can define the process or application that will run for specific Operating environments.
	The icon that will represent your application's CD or DVD when the drive is viewed with My Computer or Explorer.
	Menu commands displayed when the user right-clicks the CD-ROM icon from My Computer or Explorer.

A simple Autorun.inf example:
	[autorun]
	open=autorun.exe
	icon=autorun.ico

A complex Autorun.inf example:
This example is used in the following section for complete definition and descriptions.
	[autorun]
	open=filename.exe /argument1
	icon=\foldername\filename.dll,5
	[autorun.mips]
	open=filenam2.exe
	icon=filename.ico
	[autorun.alpha]
	open=filenam3.exe
	icon=filename.ico
	[autorun.ppc]
	open=filenam4.exe
	icon=filename.ico
	shell\install = &Install
	shell\install\command = setup.exe
	shell\uninstall = &UnInstall
	shell\uninstall\command = Uninstall.exe
	shell\readme = &Read Me
	shell\readme\command = notepad readme.txt
	shell\help = &Help
	shell\help\command = helpfilename.hlp

This section describes the configuration of the Autorun.inf file and each of the potential items.

Example Autorun File:	Description:
[autorun]	[autorun] is the primary, required section name.
open=filename.exe /argument1	Open is the keyword to determine what action to take upon insert notification.
	filename.exe is the value defining the application that will be automatically started.
	/argument1 is the argument, parameter or switch passed to the application being run. Logically, any command line parameters used must be supported by the application.
icon=\foldername\filename.dll,5	Icon is the keyword to determine the icon used for the disk.
	filename.dll is the value defining the file containing the icon.
	,5 is the argument to the icon resource defining which icon to display.
Note: By default, the system looks for the file in the root directory of the inserted disk. If you want to access a file located in a specific folder or subdirectory, specify a path relative to the root. Example: open = foldername\filename.exe This will not change the current directory. Although AutoPlay is the default menu item, you can define a different command to be the default by including the following line. shell = verb When the user double-clicks on the icon, the command associated with this entry will be carried out. Note: a more common method of defining the icon resouce is an explicit reference to a .ico file. Example: icon=autorun.ico Note: The icon defined representing your application's CD or DVD is the drive icon as viewed with My Computer or Explorer. Valid file types containing icons include .ICO .BMP .EXE .DLL If the file includes more than one icon, by default, the second icon in the files icon resource will be displayed.

Example Autorun File:	Description:
[autorun.mips]	Defining the autorun items for a mips machine
open=filenam2.exe	The platform specific application to run
icon=filename2.ico	The platform specific autorun icon
[autorun.alpha]	Defining the autorun items for a DEC Alphamachine
open=filenam3.exe	The platform specific application to run
icon=filename3.ico	The platform specific autorun icon
[autorun.ppc]	Defining the autorun items for a Power PC
open=filenam4.exe	The platform specific application to run
icon=filename4.ico	The platform specific autorun icon
shell\install = &Install	The Keyword defining a menu item and the Hot key for that item
shell\install\command = setup.exe	The keyword defining the operation to perform when the user selects this item
shell\uninstall = &UnInstall	Additional menu item example
shell\uninstall\command = Uninstall.exe	Additional menu item example
shell\readme = &Read Me	Additional menu item example
shell\readme\command = notepad readme.txt	Additional menu item example
shell\help = &Help	Additional menu item example
shell\help\command = helpfilename.hlp	Additional menu item example