A method and apparatus for communicating message data between a plurality of
subsystems
(201, 202, 301, 302, 303, 404, 406, 408) in the form of distributed resource
managers. The subsystems are coupled together through a coupling means (206,
306, 410) with a shared memory with at least one shared queue (308, 414)
in the shared memory. Access to the shared queue (308, 414) is available
from each of the coupled subsystems and message data can be communicated between
the subsystems via the shared queue (308, 414). Each subsystem has a long
running process (304) checking the shared queue for messages for that subsystem.