The N= delivery agent equate is used to give a delivery agent a higher or lower priority in relation to other processes. In general, this equate is useful only for programs that can affect other programs because of increased system or disk load, or for programs that are affected by others for the same reasons. This mechanism is discussed in the online manual for nice(3).

The form for the N= delivery agent equate looks like this:

N=val

Here, val is a signed integer expression that will set the "niceness" to a positive or negative value. If val is zero or missing, the niceness of the delivery agent is unchanged.

One possible application for the N= delivery agent equate might be with USENET news. Because news seldom needs to flow as quickly as normal email, its delivery agent (usenet) can be forced to run at a low system priority. Just add a line such as the following to your mc configuration file:

define(`USENET_MAILER_PATH', `/usr/lib/news/inews, N=10')

The path shown should, of course, match the actual location of inews.