The CODEVERIFYGEN security option determines the method used to verify the codefile. When a codefile is created, the MCP checks the CODEVERIFYGEN option on the initial close of a codefile to determine whether or not to generate a checksum.

The MCP generates and stores the checksum automatically when the codefile is created, and updates the checksum when the codefile is modified (for example, when WFL MODIFY is used to modify the codefile’s attributes).