As a batch oriented text file processing tool, the secondary interface requirements which describe the organization and format of the input source files, are considerably more important, since it is this interface that most clients will use most of the time.
However, we cannot relegate the presentation of outputs -- both documents and program files -- to discussion of functionality because, as a specialized tool, interscript must constrain -- or at least guide -- presentation to suit its purpose as a development environment.
Finally, we cannot omit consideration of how the implementation interfaces to the underlying operating system and its tools, because, in the development process, the client must use interscript to host the launching and management of these tools.
In summary: interscript interfacing involves everything which has
visual appearance including input source files, output documents
and program files, and presentation of client tool interfaces,
especially error output.
3.2.1. Unified command interface