System Generation Compiler › Compiler Activities

Compiler Activities

The system generation compiler maintains DC/UCF systems according to statements that you submit either online or through a batch job. You can direct the compiler to perform three types of activities:

• Store and update a system definition
• Validate a system definition
• Generate the executable form of a system

Store and Update a System Definition

For each type of entity in a system definition, corresponding statements allow you to add, modify, delete, display, and punch occurrences of the entity. For example, to add a task to a system definition, you submit an ADD TASK statement. Additional statements allow you to add, modify, delete, display, and punch the portions of a system definition that are stored as an extension of the system entity.

When you submit a statement to add a system to the data dictionary, the system generation compiler creates a system source record. When you submit a statement to add an entity other than system (a component entity), the compiler creates a source record for the entity, if one does not already exist, and an object record connecting the entity to the system you are defining.

More Information:

• For more information about compiler activities in response to add, modify, and delete requests, see Adding, Modifying, and Deleting Entities.
• For more information about compiler activities in response to display and punch requests, see Displaying and Punching Entities.

Validate a System Definition

You submit a VALIDATE statement to request that the system generation compiler cross-check the relationships between entities in the system definition. For example, in response to the VALIDATE statement, the compiler verifies that each physical terminal is associated with a single logical terminal.

Explicitly requesting validation of the system definition is an optional activity. The system generation compiler automatically cross-checks relationships before generating the executable form of a system.

Note: For more information and syntax for the VALIDATE statement, see VALIDATE Statement.

Generate the Executable Form of a System

You submit a GENERATE statement to request that the system generation compiler perform the following tasks:

• Validate the system definition
• Create the object record for the system entity
• Copy information from new and/or updated source records into the corresponding object records
• Calculate defaults and modify values where applicable
• Complete the connections between:
  • Programs and tasks
  • Tasks and queues
  • Lines and physical terminals
  • Physical terminals and logical terminals
  • Destinations and logical terminals
• Flag all entities in the system as executable

Additional steps are required to create the routine used to start up a DC/UCF system.

More Information:

• For more information about system startup, see the CA IDMS System Operations Guide.
• For more information and syntax for the GENERATE statement, see GENERATE Statement.

System Generation Compiler Activities

The following figure illustrates the activities of the system generation compiler.