On Thu, Jun 12, 2008 at 1:01 PM, Adrian Griffis <adriang63@gmail.com> wrote:
At one time, I thought DOS handled pipes basically by writing the
output of the first program to a file and then connecting the input of
the next program to the file, after the first program completed.  I
don't think it resulted in the two programs running in parallel.

Does anyone else remember this?

You are correct.  DOS didn't really have a way for those programs to be running at the same time, so it would use temp files under the hood to hide that inconvenient fact.

In order for two programs to be running at once, one had to go TSR and hook an interrupt to get some CPU time.