Invoking an application

If you define an application using Application Manager, you should also use Application Manager to invoke the application. Then at invocation, Application Manager allocates the libraries that the application requires.

Using Application Manager to define and invoke an application eliminates the requirement that all libraries must be included in the LOGON procedure. Decreasing the number of libraries allocated in the LOGON procedure decreases the time required for LOGON. Allocating libraries as an application requires them, enables an installation to make different versions of an application available.

If you use Application Manager to define an application, but do not use Application Manager to invoke the application, the libraries the application requires may not be available. Specifically, if the invocation you use establishes a new ISPF environment, the libraries that were allocated before the invocation will not be available. Examples of how a new ISPF environment can be established are:

You use ISPF SELECT with the NEWAPPL parameter.
You split the screen and cause an application to run on a different logical screen.

If you define an application using Application Manager, but cannot invoke it through Application Manager, and if the application establishes a new ISPF environment, then you must allocate the required libraries in the LOGON procedure or before starting ISPF.