To permanently set an environment variable that will persist across command prompts and through restart, use setx. By default, this is a user environment variable, not a system one. A common scenario is the need to update your PATH.
In this situation you want to add to the existing variable. You can do that by referencing the original value like this:. After reading this, you should know how to set environment variables in Windows permanently or for a single session using the GUI or the command prompt.
Another way to get the message issued is to use setx , this allows everything to be done on the command line, however requires setting at least one environment variable with setx. With Windows XP, the reg tool allows for accessing the registry from the command line. We can use this to look at the environment variables.
This will work the same way in the command prompt or in powershell. This technique will also show the unexpanded environment variables, unlike the approaches shown for the command prompt and for powershell.
When setting environment variables on the command line, setx should be used because then the environment variables will be propagated appropriately. The reg tool can take care of that, however another setx command should be run afterwards to propagate the environment variables.
Deleting a system variable requires administrator privileges. If there were other variables to set, we could just do that now. Some software programs use the information to determine where to place files such as temporary files. During installation, Windows XP Setup configures the default system variables, such as the path to the Windows files. You must be an administrator to modify a system environment variable.
System environment variables are defined by Windows and apply to all computer users. Changes to the system environment are written to the registry, and usually require a restart to become effective. Any user can add, modify, or remove a user environment variable. These variables are established by Windows XP Setup, by some programs, and by users.
The changes are written to the registry, and are usually effective immediately. However, after a change to user environment variables is made, any open software programs should be restarted to force them to read the new registry values. The common reason to add variables is to provide data that is required for variables that you want to use in scripts.
To view or change environment variables:. Need more help?
0コメント