Communication buffer exit library control over connections

The communication buffer exit library can force a drop of the connection to the client at any time.

If the communication buffer exit library returns the appropriate error return code on any of the calls to db2commexitUserIdentity, db2commexitRegister, db2commexitDeregister, db2commexitRecv, or db2commexitSend, the database manager immediately closes the connection with the client.

This capability allows the communication buffer exit library to determine, based on the buffers reviewed, if some inappropriate activity is taking place. If such a determination is made, any further action by the database manager for that connection can be prevented.