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Looks like I'm the guy to answer this one...
About one year ago, I came to Digital from Burroughs in New Jersey,
where I was District Support Specialist and Regional Product Spec-
ialist for LINC and LINC-II. Regional activities had me travelling
along the East Coast to various Burroughs/LINC prospect installat-
ions, including (yippeeeee), lots of work with LINC in Florida.
Re: .2
LINC, indeed, stands for Logic Information Network Compiler, and
is distinguished from many 4GL products in that it is not just a
report-writer, cobol-generator, or schema-generator, but rather
that it is a "complete systems generator"... one-stop-shopping.
LINC, originally developed as a source language yet now (LINC-II)
working as a menu-driven development system, presents a single,
rather user-friendly interface to the Burroughs environment.
Programmers, knowing LINC[II], do not have to have any great under-
standing of how to code an NDL, DMS-II (not 'dbs') database,
GEMCOS message control systems, or COBOL74 code. Through the
single language interface, all of that stuff, required to build
an application system, is generated automatically based on the
programmer's input.
-BTW- The above mentioned Burroughs (uh, er, Unisys) products most
closely map to Digital as follows :
GEMCOS ----- > ACMS (sort of...)
DMS-II ----- > DBMS (sort of...)
NDL ----- > DECnet (sort of...)
COBOL ----- > COBOL (no sort of on this one)
GEMCOS (Generalized Message Control System) serves as a
transaction and input-format router, deciding, based on
a transaction code, exactly which terminal or application
should receive/send input & output.
DMS-II (Data Management System-II) is a database system,
declared as a source language, which can be used to
specify and maintain hierarchical, network, or inverted-
list databases, although LINC's design philosophy more
closely resembles Relational.
NDL (Network Definition Language) is a source language that
is used to declare the physical datacomm network in terms
of d/c lines, terminals, station id's, and protocols.
COBOL74 (C.O.B.O.L.7.4.) is ANSI-standard with Burroughs
extensions, and differs, as most, in the datacomm and
database interfaces.
The design/coding process with LINC is very simplistic and straight-
forward, once you get accustomed to all that the language is really
doing for you. Be aware that it is positioned by James Martin as
"Fourth Generation Language suitable for use by DP professionals",
though Burroughs is a bit reluctant to admit to that wholeheartedly.
To code in LINC, now through the use of menus, you simply declare
or "paint" a screen format, with input fields included, and that
will, without further input from the programmer, generate the NDL,
the database (DMSII schema constructed based on input fields), the
GEMCOS system, and a Cobol application that will send/receive the
screen you've painted while allowing Add/Change/Delete/Recall
maintenance transactions, storing those transactions in the database.
You can also specify database indexes, files without screens, menus
or screens without files, inquiries, and other nifty functions.
Also included as part of the system is a report-writing function
where reports are coded using virtually the exact syntax used for
application development.
Well, on a simplistic level, I've gotta say that LINC is really
quite good. Although one is not recommended to go in and change
any software that LINC generates, it is available if desired.
You usually don't have to change anything because A) the code is
really quite clean, and B) within the proper limits of the LINC
design philosophy (relational design and access), anything that
you would want to include in the system has a syntactical state-
ment to implement it.
Productivity gains using LINC, on a simplistic level (hmmmmm, there's
that phrase again...) can be quite dramatic. For example, in demos,
specifying a complete, though simple, system to Add/Chg/Del/Inq
on transactions for, say, a Customer master file, a Product master
file, a repeating line order entry format, and a menu would take
only about �-hour to code and generate. Estimates for how long
that would take by hand-coding ranged from �-DAY to 1 WEEK, depend-
ing on the conventional coding experience of the programmer.
So, how do we beat LINC-II in the marketplace ? Try these...
- It runs on Burroughs machines (No real connectivity)
- It ONLY runs on Burroughs machines (No real portability)
- Burroughs merged with Sperry (Anybody know *WHY* ?)
- It is fine for small applications, but on the larger systems,
the tremendous overhead starts to get in the way.
- While quite productive for small application development,
the larger or more complex the system, the less productive
it becomes. (Too much interaction between the database
relations starts to thwart the simplistic approach to
design and development.
- Conventional DPeople have a hard time getting accustomed to
LINC. It is a new design philosophy for most, and the urge
to go in and tinker (f%&#-around) with the code will cause
problems for most programmers.
- If you indeed have to tinker with the code, that's when you
start to defeat the purpose of the generator, i.e., every
time you do a simple re-gen of the system, you have to re-
apply the patches that you've developed. There is no way
that I know of to automatically include your code with LINC.
- There are no external branch-outs (like calls to system services)
allowed within the language, i.e. You WILL code only in
LINC ! So, if the language can't do what you want, you're
sunk.
- Existing code cannot be incorporated or catalouged with the
new LINC systems that you develop.
The last point prevented the sale of LINC to many existing Burroughs
users. While LINC was good for small-medium size, BRAND NEW systems,
as soon as things get too complex, or as soon as you have to incorp-
orate older systems, you run into a counter-productive situation.
To sell into existing accounts, you basically had to pitch the fact
that you were recommending to the customer that he/she throw away
all the code developed over the last nn years ! Obviously, I've
been told to "take a hike..." before. (Why do you think I'm at
Digital, now ? I couldn't take the rejection ! 8^)
So, though I've gone on quite a bit, that should get you started.
Of course, if you'd like to know more, simply give me a call or
VAXmail me at the addresses below and I'll be more than happy to
help out.
Also remember that we can work around LINC from two positions :
1) LINC has a specific purpose in life, and
2) It's Burroughs, and we should stress the Digital Advantages.
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["We're UNISYS, where 0 squared is still 0"]
Wanna know more ?
DARTH::HANSON
OBIWAN::HANSON
DTN 323.4053
Enjoy !
Bob
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