The only way I know of is to use RUN, but that will only work if you RUN a .bat file that then calls the external program.

RUN launches a second copy of command.com (or cmd.exe) which will get a copy of the environment. Changes you make in the copy are lost when it exits.

Dan

>I can use getenv() to return a dos variable. But what's the best way to set a dos variable. I'd like to do it without seeing a dos window fly by.
>
>Set myvariable=myvalue
>
>I am passing a variable to an external program