CorVision Logo used by Cortex

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CorVision

CorVision is a fourth generation programming tool (4GL) currently owned by International Software Group Ltd (ISG). CorVision was originally written for the VAX/VMS ISAM environment although Cortex beta tested CorVision-10 which generated for PC's but CorVision itself stayed anchored on VMS. CorVision-10 proved more difficult than hoped, and was never released. A fourth-generation programming language (or 4GL) is a programming language designed with a specific purpose in mind such as the development of commercial business software. ... VAX is a 32-bit computing architecture that supports an orthogonal instruction set (machine language) and virtual addressing (i. ... VMS is a three-letter abbreviation with multiple meanings, as described below: Virtual Memory System (another name for OpenVMS), an operating system Variable message sign, an electronic traffic sign often used on highways Visual Memory System (better known as Visual Memory Unit), a storage device for the Sega Dreamcast console... ISAM (Indexed Sequential Access Method) is a file management system developed at IBM that allows records to be accessed either sequentially (in the order they were entered) or randomly (with an index). ...

The Birth Of CorVision

CorVision can be traced back to 1972 when Lou Santoro and Mike Lowery created INFORM for the newley formed company Standard Information Systems (S.I.S.). INFORM contained some of CorVisions basic utility commands such as SORT, LIST and CONSOLIDATE. Some of the first users of INFORM were New England Telephone, Polaroid and Temple Barker & Sloan. By 1972 S.I.S. had offices in LA, Garden Grove CA, Minneapolis, Chicago, Boston, New York City, Washington DC, Charlotte, Raleight, Atlanta and Phoenix. Inform is a programming language and design system for interactive fiction, created in 1993 by Graham Nelson. ...

Establishing CorVision

Between 1976 and 1977 Ken Levitt and Dick Berthold of S.I.S. ported INFORM from the CDC-3600 to the PDP-11/70 under IAS. They called this new tool INFORM-11. Ken Levitt and Dick Berthold needed a company to market their new product so they formed the company Cortex. INFORM-11 was first used to deliver a 20 user order entry system at Eddie Bauer.

Between 1981 and 1982 Cortex received significant investment from A. B. Dick. Using this new investment Cortex ported INFORM to Digitals new VAX/VMS, adding compiled executables. INFORM-11 was promoted by both Cortex and Digital as a pioneering rapid application development system.

In 1984 Jim Warner encapsulated INFORM in a repository-based development tool and called it Application Factory. INFORMs PROCESS procedural language became known as BUILDER within Application Factory. In 1986 the name of Application Factory was dropped in favor of the name CorVision.

CorVisions Heyday

Between 1986 and 1989 CorVision experienced its heyday. CorVision quickly became known as a robust and capable tool for rapidly building significant multi-user applications. The addition of Relational Database support attracted major accounts. Cortex quickly became an international company. It has been suggested that this article or section be merged into Relational model. ...

In 1992, CorVision version 5 was released with Query and support for Unix. Query allowed read-only access by users and developers to a systems Database backend. Where this seemed a desirable facility, allowing users to create ‘use once then throw away’ reports without calling on developers this had a nasty habit of causing performance issues. Users often did not understand the database structure and could send large queries to the processing queues causing system wide issues.

In 1993 Cortex started supported vesting to Digital's new 64-bit Alpha line. In 1994, International Software Group Ltd (ISG) purchased Cortex. Digital Equipment Corporation was a pioneering company in the American computer industry. ... In computing, a 64-bit component is one in which data are processed or stored in 64-bit units (words). ... DEC Alpha AXP 21064 Microprocessor The DEC Alpha, also known as the Alpha AXP, is a 64-bit RISC microprocessor originally developed and fabricated by Digital Equipment Corp. ...

The Beginning of the End for CorVision

As early as 1987, Cortex recognised the growth in the popularity of the IBM PC, supporting diagrammatic editing of menus and data relationships in CorVision. In 1993 a client-server version was released, but not widely adopted. In 1997 ISGs work on CorVision-10 which was to herald the rebirth of CorVision onto the IBM PC platform stopped. CorVision-10 was proving very difficult to port and ISG finally refused to spend any more money on the now dated system. 1994 saw the last innovative CorVision release: V5.11. The extra-fee Y2K release, V5.12.2, marked the end of development. One of the first PCs from IBM - the IBM PC model 5150. ... The year 2000 problem (also known as the Y2K problem and the millennium bug) was a flaw in computer program design that caused some date-related processing to operate incorrectly for dates and times on and after January 1, 2000. ...

CorVision as a Legacy System

CorVision still exists in a handful of companies that have not yet found time or money to upgrade their exisiting mainframe systems. As CorVision runs on the VMS environment it is very stable but the search for CorVision developers and contractors to support these ageing systems is a constant headache for IS Managers who still manage these legacy systems. Since around 1999, companies have started appearing offering conversion tools to convert BUILDER code to compiled Visual Basic and Java. In 2005 a CorVision guru by the name of Michael Rennie attempted to revive the CorVision franchise with a proposal for CorVision .NET (CV.NET) written using Microsofts .NET Framework. CV.NET is currently in the Proof of Concept stage. The four colored boxes is the logo of VBA, and the two drums above them symbolize database connectivity Visual Basic (VB) is an event driven programming language and associated development environment prototyped by Alan Cooper as Project Ruby, then bought and vastly improved upon by Microsoft. ... The term Java can refer to: In geography: Java (island), Indonesia, the most populous island in the world Javanese language, a language widely spoken on the island of Java Java coffee, a variety of coffee plant which originated on the island of Java, or a slang word for coffee Java... The Microsoft . ...

Application Development

A brief explanation of application development using CorVison.

Application Parameters

The first step in developing an application with CorVision is to fill in the parameters which control the miscellaneous aspects concerning application-wide functions.

The Parameters fall into five groupings as follows:

1. Heading, Title and Menu Information for the application.
2. Development parameters which affect the CorVision working environment.
3. Run-time parameters which affect run-time execution of the application (including Batch & Print Queue control).
4. Application-wide navigation options.
5. Application-wide standard menu items.

Under most circumstances the defaults for all these parameters will be satisfactory at the start of an application development. They can, however, be changed at any time during the development as required. At run-time, procedures access the parameters file (WP) to utilise the latest settings found there. The application will then run accordingly.

Help

You can call the CorVision on-line (and context-sensitive) help at any time by pressing either the F2 key or the F1 followed by F2 key. In the former case, help will be displayed relevant to the field you are completing; in the latter case, a help subsystem will appear to select a help topic and allowing viewing up and down levels.

Status Screen

CorVision keeps the information behind the Status Screen up-to-date so that it indicates the current state of the development process. The screen should be read from left to right, top to bottom. The left hand side indicates specification tasks that need doing. The right hand side indicates generation tasks that need doing. Both sides show the date when the specification was last changed or when the task was last performed.

Changes or Additions to Specification and what they cause changes to.

Dictionary, Datasets and Keys

• Generate *.CRE, build Links

Dictionary, Datasets, Keys

• Screens, Reports, Dataviews

Screens, reports

• Generate *.SCR, *.RPT, *.JOB

Menus

• Generate *.DO

Under any circumstances the STATUS screen will always refelct what you have done and what you still need to do.

Field Search

CorVision provides a very useful feature for anyone involved in maintaining applications. This feature is called Field Search. Field Search allows you to investigate and analyse the use of fields in different aspects of the application. In this way, the impact of changes can be assessed before they are made and that assessment of the work involved quantified.

This facility is accessed through the Review Specification gateway.

To provide complete specification details in hardcopy form, CorVision has the Run Reports option, also from the Review Specification menu. Over 80 different types of report can be produced and a full list is provided in Chapter 36 of the CorVision manual (volume III). Component Specification Reports (CSRs), as they are known, can also be produced for tentative, unreferenced and unresolved items. These reports can be important during development for quality assurance and project control.

Procedures & Processes in CorVision

The key to understanding CorVision is understanding PROCEDURES. The procedures in CorVision eventually become Executable Images (.EDO's).

Three types of procedures are:

Screen Procedures

• A Procedure of this type consists of the Menu selection and any key screens and data screen. These are generated and compiled together. If you like you can look upon the screen procedure as the MAIN procedure which is called MAIN by default in CorVision. N.B. It excludes any reports or custom procedures. These are generated and compiled separately.

Jobstream / Report Procedures

• A Procedure of this type consists usually of one step to produce a report. It is generated and compiled separately from the screen procedure.

Custom Procedure

• A Procedure of this type is writtenentirely in BUILDER, the CorVision 4GL. It too is generated and compiled separately from the other two types.

It is not essentially true to consider a procedure as a program. In fact, a procedure is a set of instructions (BUILDER Commands) which build a program. A program in BUILDER is actually called a Process not a program. A Procedure therefore is a set of BUILDER commands which instruct BUILDER to build a process and save this in the program library as a compiled file with a .SAV extension.

Screen and custom procedure structures are kept in a separate library called RT0. RT0 is the run time library. For jobstreams, the structures are embedded in the generated code but are basically very simple. The three types of procedures are designed to serve the following areas of functionality in an application.

Screen Procedures

• Interative entry and updating of datasets in a menu-based system with navigation facilities to move between and within functions.

Jobstream Procedures

• The extraction, selection and presentation of records from the datasets in the form of various layouts for reports.

Custom Procedures

• These procedures are completely hand-coded in BUILDER and as such can basically achive any function which is not covered by screens or jobstream procedures. Normally custom procedures will be batch orientated updates but this is not necessarily the case.

Data Independence

Data independence is a powerful feature of CorVison. The data structures that are to be manipulated by BUILDER processes are kept as separate files within the BUILDER system. Each dataset specified for the application will have a corresponding structure file and key structure file kept within BUILDER in the Quality Control area.

When a process is compiled by a .DO or .JOB command file, the data structures are "bound" to the process at that time thus "binding" of data structures takes place at the precise moment the process is compiled for testing.

Keeping the structures (field and record definitions) and the key structures (index key definitions) separate enables the dataset definitions to be altered and updated as the application is developed. This provides a powerful prototyping environment where source code and data structures can be continually changed and then brought together at compile time for testing.

By inspecting the .DO or .JOB command file for a procedure, you will find that the structures and key structures are actually loaded before the process is compiled. This loading is achieved by the generated .LOA file. The command DO PR0:MAIN.LOA is an example of the dataset structures and key structures being loaded for the procedure MAIN prior to the compilation of MAIN.SAV. BUILDER always assumes that the data structures are already loaded when it compiles a process. The process compilation "binds" the data structures to the process code.

Creating a Procedure

• Add / Change the procedure specification
• (Progressively) Construct the application components
  • Menus
  • Screens
  • Reports
  • Custom Code
• (Progressively) Generate the compilable files
• Compile the procedure

After Generating the Procedure

The following files are created:

• .DEF :Define fields used within the procedure.
• .DFS :Define (.DEF) files used within the procedure.
• .DO  :Generated BUILDER for controlling the running / compiling of the procedure.
• .IOS : the procedure.
• .LOA :Generated BUILDER for controlling the loading of all required datasets used by the procedure.
• .SCS :List of all screens used in the procedure

The following files can also be added:

• .DCL :DIGITAL command language file.
  • Define specific CorVision logicals.
  • Define any other processing before the procedure is run.

The following files are created after compiling: DCL is the standard Command line interface (CLI) adopted by most of the operating systems that were sold by the former Digital Equipment Corporation (which has since been acquired by Hewlett-Packard). ...

• VAX 32 bit
  • .SAV
  • .EDO
• ALPHA 64 bit
  • _TV.SAV (after vesting)
  • _TV.HIF (after vesting)
  • _TV.EDO (after vesting)