Because the Validator and the Generator are separate executables the appropriate filenames are passed as command line parameters. The command line syntax is described in Sections 5.13 and 5.14 for the Validator and the Generator respectively.
The second layer of internal communication is to pass status report from the Editor, the Validator and the Generator to the Controller module. This could be achieved redirecting standard input and output streams according to inter-process communication described in Section 5.5. The most important reports are visualized as a separate communication window. Common messages are displayed using Controller's status-bar and Editor's status-bar.