ViewPoint Manual

Functional Description

ViewPoint Manual—426801-001

5-4

ViewPoint TCP

The ViewPoint TCP is the terminal control process portion of a Pathway application (see

Introduction to Pathway). The TCP has three major functions: terminal management,

code management, and message management.

The terminal management function routes information to and from each logged-on

operator. The code management function manages the multithreaded execution of the

network application programs (SCREEN COBOL programs) for each operator. The

message management function communicates with the remainder of the system.

The operator default subvolume contains your TACLCSTM file, your clipboard

(ZZVPCLIP) file, and various other files that your user ID owns.

The ViewPoint program subvolume contains SCREEN COBOL programs, various

components of Pathway and TACL, and other files that all operators must be able to

access. The ViewPoint data subvolume holds the display caches for events and status.

The remaining paragraphs under this subheading separately discuss each of the three

logical parts of the application—TACL, status logic, and events logic.

TACL

When your operator terminal is in TACL mode, the terminal communicates directly with

your TACL command interpreter process. The ViewPoint TCP is effectively

disconnected from your terminal, even though servers can be actively performing event

functions for you, and action and critical events are reported on the twenty-fifth line of

the screen.