............................Figures


Figure 1-1 Typical Electronic Mail Configuration	11
Figure 1-2 Gateway Between Different Communications Protocols	14
Figure 1-3 How Mail Programs Interact	17
Figure 1-4 How `sendmail` Uses Aliases	19
Figure 1-5 Local Mail Configuration	25
Figure 1-6 Local Mail Configuration With a UUCP Connection	26
Figure 1-7 Two Domains and a Gateway	28
Figure 3-1 Interaction of `sendmail` With Other Mail Programs	61
Figure 3-2 Rewriting Set Semantics	92