How to update PATH variable permanently from Windows command line?

Question

If I execute set PATH=%PATH%;C:\\Something\\bin from the command line (cmd.exe) and then execute echo %PATH% I see this string added to the PATH. If I close and open the command line, that new string is not in PATH.

How can I update PATH permanently from the command line for all processes in the future, not just for the current process?

I don't want to do this by going to System Properties → Advanced → Environment variables and update PATH there.

This command must be executed from a Java application (please see my other question).

Answer 1

You can use:

setx PATH "%PATH%;C:\\Something\\bin"

However, setx will truncate the stored string to 1024 bytes, potentially corrupting the PATH.

/M will change the PATH in HKEY_LOCAL_MACHINE instead of HKEY_CURRENT_USER. In other words, a system variable, instead of the user's. For example:

SETX /M PATH "%PATH%;C:\your path with spaces"

You have to keep in mind, the new PATH is not visible in your current cmd.exe.

But if you look in the registry or on a new cmd.exe with "set p" you can see the new value.