Overlay Generation Language

The architecture of Overlay Generation Language (OGL) centers around the creation and management of AFP overlays within a mainframe environment. The core components include the OGL compiler, the overlay object library, and the print drivers. The OGL compiler is a batch program invoked via JCL.

It processes OGL source files, which contain commands such as CREATE OVERLAY, DEFINE FIELD, DRAW LINE, and INCLUDE OBJECT. The compiler generates AFP overlay objects, which are stored in the overlay object library. The overlay object library is typically a partitioned dataset on the mainframe.

Print drivers, such as those provided by IBM, are responsible for merging the AFP overlay objects with the print data during the printing process. Communication between these components occurs through the mainframe's internal mechanisms. The OGL compiler reads source files from the file system.

The print drivers access the overlay objects from the overlay object library. There are no specific network requirements for OGL itself. Security is managed through the mainframe's security features, such as RACF, which controls access to OGL source files, the overlay object library, and the printing subsystem.

The OGL architecture is designed for efficient AFP overlay generation within the mainframe environment, ensuring seamless integration with existing printing workflows. The primary data storage mechanism is the mainframe's file system and the overlay object library.