Environment variables

In the DOS environment memory is reserved for user defined variables. Enviroment variables can be used for different things:

To list all environment variables in memory:

SET more

To show the value of a single environment variable:

SET CLASSPATH

ECHO %CLASSPATH%

To change the value or create a single environment variable:

SET CLASSPATH=.;C:\JDK

To append to an existing environment variable:

SET CLASSPATH=%CLASSPATH%;C:\MY_JAVA

To clear or delete a single environment variable:

SET CLASSPATH=

Note when using SET from the command prompt then the environment variable will only live temporarily and will be forgotten when the command environment closes. To make a permanent environment variable move the SET of the variable to the AUTOEXEC.BAT.

Related Configure how much memory to allocate for environment variables
Related Batch file input parameters are accessed like environment variables

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