Re: Service programs

Service Programs are DLL (Dynamic Link Load Libraries). The whole idea is
to encapsulate some form of service which is sounds like what you have
here. A program that provides services.

The primary advantages of a service program are:

1. You are calling procedures instead of making program calls. Procedures
are much, much faster than program calls. When you make a program call,
what is you get completely undetermined. It may require zoned fields but
you can pass it packed or character or anything else.
2. The biggest single value to a service program is that you have multiple
points of entry, you can expose multiple procedures. You break problems
down into small pieces. Their is only one point of entrance on a program.
If you want to have the program do multiple things, you have to overload
the parameters and pass control as to what you want the program to do.

So the question becomes, does the program provide multiple services, does
it have different functions? If it doesn't, it might not be worth
re-writing to make a service program but if you are working any new
applications, I would always use a service program.

The hard part for most people in using service programs is that they just
try to use a service program as a called program and design it that way but
that is not the way you design them.


On Mon, May 15, 2017 at 12:24 PM, Booth Martin <booth@xxxxxxxxxxxx> wrote:

Why would one use a service program instead of a stand-alone program? and
the opposite?

For the sake of discussion, lets use a FAQ program that is for the F1 key
in programs and is system wide. Its the same everywhere - the only change
being the FAQ data file which is determined by the library list. It
displays FAQs and can be edited to add, delete, and update questions. Its
an actual application I use, as a standalone program.

So, I see Service Programs mentioned and think I should change how I do
it. Then I look at the process and scratch my head. Why would I make the
change? What is the benefit? The more I read about it, the faster I
scratch.

--
This is the Midrange Systems Technical Discussion (MIDRANGE-L) mailing list
To post a message email: MIDRANGE-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/midrange-l
or email: MIDRANGE-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/midrange-l.

Please contact support@xxxxxxxxxxxx for any subscription related
questions.

Help support midrange.com by shopping at amazon.com with our affiliate
link: http://amzn.to/2dEadiD