[Exim] Lost with aliases, pipes, directors and transports

Lost is a good descrption...

I'm still kind of new to Exim and have not yet mastered some of its
features...

I've got a server setup and so far, it is doing great.

Now I am in the process of getting ready to move over some existing
mail-to-stuff things that I have been using for a while on our other
server (running Smail) and I'm not really clear how to make them
work.

For the most part, they all do a variation of the following from the
aliases file:

inputname1: "|/usr/local/processor/process idinfo1"
inputname2: "|/usr/local/processor/process idinfo2"

Above is just a generic example, but they all operate the same.

In all cases, the "process" is a suid module (or wrapper that calls a
specfic module) that is owned by a unique UID and GID setup for this
specific purpose. They have their own log files and don't spit back
any error messages even if something is wrong, instead the append to
their own log.

Most of them have email directed to them which they then strip out
what they are looking for and either queue up for another process or
store in a file or database somewhere.

A similar real world like example would be if you subscribed to a
public service that sent you stock information about a specific
stock. The mail would be directed to one of these and it would strip
out the specific information and store it into a database.

Currently, when I run this, I get in paniclog:

Neither the system_aliases director nor the address_pipe transport
set a uid for local delivery of |/usr/local/processor/process
idinfo1

Okay... I see that I need to either modify or create a new director
and transport with the proper UID. But, what would be a good example
of what that would look like?

I think I need to either modify the following or create a new one:

address_pipe:
driver = pipe
return_output

system_aliases:
driver = aliasfile
file = /etc/aliases
search_type = lsearch
user = mail
group = mail
file_transport = address_file
pipe_transport = address_pipe

But it is not clear to me how what I name it is related back to the
aliases entry...

As you can see... I am confused..

I see tons of options for these, but don't know which ones I would
require.

Is there a example somewhere that shows the relationship of the
aliases entry, with a matching transport and director?

--
Kevin