Control Language (CL) is a set of commands used to control operations and request system-related functions on the IBM i System, and on the earlier generation AS400 and iSERIES machines. The purpose of CL is comparable to Job Control Language (JCL) on mainframe computers, but CL offers greater functionality.
Here are some key purposes and features of CL:
- Controlling system operations: CL commands allow users to manage various aspects of the AS/400 system, such as creating libraries, managing output queues, and controlling job processing.
- Requesting system functions: Users can employ CL commands to request specific actions from the system, like retrieving object information or displaying user profiles.
- Batch processing: CL commands can be grouped together into CL programs that can be compiled and executed in batch mode.
- Interactive use: CL commands can be entered directly on the AS/400 command line for interactive execution.
- File management: CL includes commands for file operations like copying, redirecting output, and creating directories, similar to PC-DOS commands.
While CL is feature-rich, it is not considered a high-level language suitable for complex applications like payroll processing.
The naming convention for CL commands is based on English and typically combines a verb and a noun, such as CRTLIB (Create Library). Examples of CL commands include ADDLIBLE (Add Library List Entry), CHGPGM (Change Program), and DSPOBJAUT (Display Object Authority).