DOS AUTOEXEC.BAT

AUTOEXEC.BAT is a special DOS batch file that is automatically executed whenever the computer is started or restarted. It must be stored in the root directory.

It is used to load TSR (Terminate and Stay Resident) programs that stay in memory and "pop up" whenever you call them. It's also used to start an application when the computer is turned on, perhaps a menu program that launches a variety of applications.

Two common commands in AUTOEXEC.BAT are:

   PROMPT - Usually prompt $p$g.
   PATH   - The Path line contains the
            directories you want access to
            no matter which directory you're in.

To load or run a program, enter the program name on a separate line. Any DOS commands in AUTOEXEC.BAT will be executed like a normal DOS batch file.

The following example sets the prompt and path, loads the Doskey program in the DOS directory, switches to the LOTUS directory and runs the 123 program:

         prompt $p$g
         path c:\data;d:\words;e:\budget
         c:\dos\doskey
         cd \lotus
         123

Manual changes to AUTOEXEC.BAT are done with a text editor such as the DOS Edit and the Windows Notepad utilities. Any word processor that can import and export ASCII files can also be used. To use the DOS Edit program to edit the AUTOEXEC.BAT file, type:

   cd \               switch to root directory
   edit autoexec.bat  open AUTOEXEC.BAT for editing

To quit DOS Edit after making the changes you required, press Alt F, then X and Enter.

Remember!
AUTOEXEC.BAT must be stored in the root directory.

Your Configuration Files Get Tampered With
Install programs may edit your AUTOEXEC.BAT and CONFIG.SYS files during installation. For example, they may want to add the new directory to the path or to set an environment variable (see DOS Set). They may also need to add a new driver. You are generally informed that this is being done and often shown the changes as they are made. The original files are usually renamed with a different extension and left on the disk.

If you want to delete the application soon after it was installed, you can rename these files back to AUTOEXEC.BAT and CONFIG.SYS (after deleting the current ones). However, after several software installations, you may not remember which is which, and all these previous configuration files may have little value unless carefully inspected.