The Model Railway
|
Process Communication FrameworkA control program has basically to decide wether a train may enter a certain block or not. There are generally two ways of implementing the mechanisms for meeting these decisions:
Students participating in the lab courses have to follow the second way. Therefor
the files
PERMISSION versions
of the library.
For getting informations concerning other block sections, a process has to send a request to the appropriate process. The other way round, a process has to answer all requests sent to him again by sending a message.
To free the application programmer from the need of implementing the message
passing facilities, they are provided with the library. The function prototypes
and constants are located in
The block section processes are only being regarded conceptually as processes.
In fact, they are still part of the By using this process communication framework, students are introduced to the problem of creating a program in a "distibuted memory system" environment. Consequently, they should get a view for at least some sort of problems which come up when an application runs distributed, e.g. over a network (LAN, Internet etc.) or on a multi-processor system.
Clemens Grelck generated on: Mon May 31 10:21:01 MET DST 1999 |