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Mailer Creation

Mailers maintain contexts and process lists. All communication operations use mailers. Mailers are created through a loose synchronization  between the members of the proposed mailer's process list. A single process creates the process list, placing itself first in the list, and initiates the ``mailer-open'' call with this process information; it's called the ``Postmaster'' for the mailer, as initiator. The other participants receive the process list as part of the synchronization procedure. A special reactive process, the ``Postmaster General,'' maintains and distributes zip codes as mailers are opened; essentially the zip code count is a single location of shared memory.  Below, each class defines an ``open'' function to create its mailer.

Guy Robinson
Wed Mar 1 10:19:35 EST 1995