This chapter describes MVS™ services that are provided to help you build and use your subsystems when performing the following tasks:

• Adding your subsystem
• Initializing your subsystem
• Defining what your subsystem can do
• Changing what your subsystem can do
• Activating your subsystem
• Deactivating your subsystem
• Swapping subsystem functions
• Storing and retrieving subsystem-specific information
• Defining subsystem options
• Querying subsystem information
• Maintaining information about your subsystem