Data space interface

Application programs that expect to receive a large volume of messages should use the data space interface. For this interface, messages remain in the data space until they are freed by the application program or until the data space fills, whichever occurs first.

The following exit routines and functions run under the same task:

Read queue exit routine
TPEND exit routine, if there is one
MIBConnect function
MIBDisconnect function

Figure 1 describes the relationship between the application program and CMIP services for an application program using the data space interface.

Figure 1. Using CMIP services with the data space interface

An application program that uses one or more of the individual API functions must load the entry point for that function from LPALIB. All modules are placed in LPALIB when the operating system is initialized. Once the entry points for the APIs are known, the application program can call an API function directly. See Table 1 for the module names of each API function. Application programs can have any tasking structure. The functions for reading and freeing messages in the data space are serially reusable only.