What's the difference between %TMP% and %TEMP% in Vista environment variables?

Brann picture Brann · Feb 24, 2009 · Viewed 17.1k times · Source

On my computer, the environment variables %TMP% and %TEMP% both point to the same location.

Are those for backward compatibility issues only, or is there a real difference?

Answer

TorgoGuy picture TorgoGuy · Feb 24, 2009

It is for compatibility. It goes all the way back to DOS. Since there were no standards, some DOS (and Win 3.x) applications would look for the %TMP% environment variable and others would look for %TEMP%. You were best off if you set both of them in the AUTOEXEC.BAT file.

Windows NT set both of them automatically just to make sure all of the apps continued to work OK. %TEMP% is the standard now, but %TMP% lives on.

EDIT: Looks like Richard already mentioned the DOS aspect in a comment.