Useful Windows commands and variables

I’ve got loads of commands and variables that I use periodically, but I forget them often.

I only have a few that spring to mind now, but I’ll add to this when I remember more!

Useful Commands

  • Display the OS version details:
    winver

  • Display the computer name:
    hostname

Useful Variables

To view a variable, at a command prompt, type:

set VariableName
Variable Type Description
%ALLUSERSPROFILE% Local Returns the location of the All Users Profile.
%APPDATA% Local Returns the location where applications store data by default.
%CD% Local Returns the current directory string.
%CMDCMDLINE% Local Returns the exact command line used to start the current Cmd.exe.
%CMDEXTVERSION% System Returns the version number of the current Command Processor Extensions.
%COMPUTERNAME% System Returns the name of the computer.
%COMSPEC% System Returns the exact path to the command shell executable.
%DATE% System Returns the current date. Uses the same format as the date /t command. Generated by Cmd.exe. For more information about the date command, see Date
%ERRORLEVEL% System Returns the error code of the most recently used command. A non zero value usually indicates an error.
%HOMEDRIVE% System Returns which local workstation drive letter is connected to the user’s home directory. Set based on the value of the home directory. The user’s home directory is specified in Local Users and Groups.
%HOMEPATH% System Returns the full path of the user’s home directory. Set based on the value of the home directory. The user’s home directory is specified in Local Users and Groups.
%HOMESHARE% System Returns the network path to the user’s shared home directory. Set based on the value of the home directory. The user’s home directory is specified in Local Users and Groups.
%LOGONSEVER% Local Returns the name of the domain controller that validated the current logon session.
%NUMBER_OF_PROCESSORS% System Specifies the number of processors installed on the computer.
%OS% System Returns the operating system name. Windows 2000 displays the operating system as Windows_NT.
%PATH% System Specifies the search path for executable files.
%PATHEXT% System Returns a list of the file extensions that the operating system considers to be executable.
%PROCESSOR_ARCHITECTURE% System Returns the chip architecture of the processor. Values: x86, IA64.
%PROCESSOR_IDENTIFIER% System Returns a description of the processor.
%PROCESSOR_LEVEL% System Returns the model number of the processor installed on the computer.
%PROCESSOR_REVISION% System Returns the revision number of the processor.
%PROMPT% Local Returns the command prompt settings for the current interpreter. Generated by Cmd.exe.
%RANDOM% System Returns a random decimal number between 0 and 32767. Generated by Cmd.exe.
%SYSTEMDRIVE% System Returns the drive containing the Windows XP root directory (that is, the system root).
%SYSTEMROOT% System Returns the location of the Windows XP root directory.
%TEMP% and %TMP% System and User Returns the default temporary directories that are used by applications available to users who are currently logged on. Some applications require TEMP and others require TMP.
%TIME% System Returns the current time. Uses the same format as the time /t command. Generated by Cmd.exe. For more information about the time command, see Time
%USERDOMAIN% Local Returns the name of the domain that contains the user’s account.
%USERNAME% Local Returns the name of the user who is currently logged on.
%USERPROFILE% Local Returns the location of the profile for the current user.
%WINDIR% System Returns the location of the operating system directory.

Find out more about environment variables.