Editing Environment variable (section)

=== Assignment: DOS, OS/2 and Windows ===
In DOS, OS/2 and Windows command-line interpreters such as <code>COMMAND.COM</code> and <code>CMD.EXE</code>, the '''<code>[[SET (DOS command)|SET]]</code>''' command is used to assign environment variables and values using the following arguments:
<syntaxhighlight lang="batch">
 SET VARIABLE=value
</syntaxhighlight>
An environment variable is removed via:
<syntaxhighlight lang="batch">
 SET VARIABLE=
</syntaxhighlight>

The '''<code>SET</code>''' command without any arguments displays all environment variables along with their values; '''<code>SET &quot;&nbsp;&quot;</code>''', zero or more spaces, will include internal variables too. In <code>CMD.EXE</code>, it is possible to assign local variables that will not be global using the '''<code>SETLOCAL</code>''' command and '''<code>ENDLOCAL</code>''' to restore the environment.

Use the [[switch (command line)|switch]] '''<code>/?</code>''' to display the internal [[man page|documentation]], or use the [[help (command)#DOS|viewer]] '''<code>help</code>''':
<syntaxhighlight lang="batch">
 SET /?
 HELP SET
 SETLOCAL /?
 HELP SETLOCAL
</syntaxhighlight>


In [[PowerShell]], the assignment follows a syntax similar to Unix:

<syntaxhighlight lang="powershell">
 $env:VARIABLE = "VALUE"
</syntaxhighlight>