These environment variables are created by parts of DOS or can be set to
custom values to modify how DOS acts:

APPEND    Data search path visible in the environment after Append /E.

COMSPEC   The name and location of the command processor.

CONFIG    The item chosen from a MultiConfig Menu in CONFIG.SYS.
Typical usage is to test this value in AUTOEXEC.BAT.  For
instance:
IF (%CONFIG%)==(DAN) Echo Hi Dan!
or
Goto %CONFIG%
.
.
.
:NO_EMS

COPYCMD   Option settings for the Copy command (DOS 6.2+).

DIRCMD    Option settings for the Dir command.

DOSSHELL  The directory for DOSSHELL.INI.

MSDOSDATA The directory for some configuration and setup files used by
DOS 6.0+ Msbackup, MSAV, Undelete.

PATH      The command search path.

PROMPT    The command prompt as set via the Prompt command.

TEMP      The location for I/O Redirection piping files.  Also used for
temporary files by Dosshell, Windows and other programs.
Setting this to a large RAM disk can speed up Windows printing
dramatically.

Note: A few older programs look for TMP rather than TEMP.

WINPMT    The command prompt for DOS sessions under Windows.  When a DOS
session starts, Windows swaps PROMPT and WINPMT.

windir    In a DOS session under Windows, this identifies the drive and
directory where Windows is stored.

See Also: DOS Environment
- -

Predefined Environment Variables