In an RPG IV module, you can define global files which are available to every procedure in the module, or local files which are only available to one procedure. Global files are defined in the main source section, between the Control specifications and the Definition specifications. They can be primary, secondary, table, or full-procedural files. Local files are defined within subprocedures, between the Procedure specifications and the Definition specifications of the subprocedure. They can only be full-procedural files. Input and Output specifications can be defined to handle the field data for global files.
Input and Output specifications are not supported for subprocedures, so all input and output operations must be done using data structures for local files.