HP 3000 Manuals HP 3000 Manuals
Chapter 7 Interprocess Communication
Via the MAIL Facility
A number of MPE V/E-based systems use the MAIL facility to direct the
communication of information between processes. This information
transfer, however, is restricted to upward or downward paths through the
process tree structure, so that any process can communicate only with its
parent or children. Between any parent/child pair, only one such
transfer is allowed at any particular time. The MAIL facility should not
be confused with message files, which can be used to transfer information
between unrelated processes.