|User's Guide: Small Ada 95 Object Database; Version 0.1.0; Document Revision $Revision: 1.9 $|
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When starting up, the client tries to establish a communicaton relation ship to the server. This will be done in the following steps
The client asks the server to provide a connection address by sending a message with the message id 1.
The server provides a connection address and allocates at the same time a shared memory area which is associated with the connection.
Connection addresses are identical with message identifiers of the msgsnd, msgget. The range 1..1000 is reserved for unqualified messages from client to server. Message 1001..2000 are used for communication from the server to the client. Identifier 2001..3001 are used for communication from the server to the client.
A communication dialog in both directions is based in the shared memory area where the objects are placed an an IPC message with the appropriate message identifier.