Hello,
I wouldn't venture to say that C is better than RPG or vice versa, but in
terms of prototypes I agree with Brian. If anything, I'd say that C has
better prototyping abilities in that you can overload procedures -
C does not support overloading. Maybe you're thinking of C++?
RPG's prototypes have more capabilities than the C ones do. They also
provide better safety checking, and require less knowledge of pointers.
Basically, they learned from C's mistakes.
However, C prototypes are very good as well. The varargs syntax
provides some capabilities that RPG can't provide (albeit, at the
expense of safety.) I use both languages on a regular basis, and I
certainly wouldn't make a decision of which language to use based on the
prototypes.
One thing that C has that RPG doesn't have is the ability to code a
prototype for a procedure pointer, and then dereference it. This
provides the ability to put a prototype in a data structure and call it
from the data structure with something like:
myObject->myProc(one, two, three);
And that's a useful capability that RPG doesn't have. But... it's
another small thing.
RPG on i5/OS is better for business applications than C on Linux for
these reasons:
Integrated database support. There's a big difference in the amount of
work required to interface with a database via ODBC APIs, and the amount
of work required to declare an F-spec and code a CHAIN statement. The
RPG method is much, much easier, and requires far less knowledge of how
computers work. Even if you want to use SQL, RPG's embedded SQL is
vastly superior both in performance and ease of coding than calling the
ODBC APIs.
Support for true decimal fields. There's no variable that's comparable
to a packed or zoned decimal field. You either have to use floating
point (and all disadvantages that go with that) or you have to keep your
fields in an integer, and manually keep track of the decimal positions,
requiring much more code and much more work. You have to know exactly
how these data types work and what their limitations are... in other
words, you have to understand more about the way your computer does math.
Proper Error Handling. The i5/OS method of call stacks with *ESCAPE
messages is a more robust and versatile system than Linux process groups
and signals. It helps you make sure you get your application written
correctly and makes it generally more stable. The Linux/Unix method
requires more knowledge of computers and how they work to make the code
completely stable.
All of this is what makes RPG a better language for writing business
rules. You can just write the business rules, concentrating on the
business objectives, without having to spent a lot of time considering
how the computer works and how best to use the computer's resources.
On the other hand, the system i5 has dreadful graphics, sound, etc,
capabilities. Linux blows it out of the water in those areas. Linux
has drastically more applications available for it, and most of those
applications are free.
There are all sorts of pros and cons. It's absurd to say that i5/OS is
better than Linux. It's absurd to say the opposite, as well. It's
absurd to say RPG is better than C or that C is better than RPG. Both
sides have strengths and weaknesses, and which one is "better" depends
entirely on what you're doing.
As a central server that hosts business rules, business databases, etc,
i5/OS is the better choice in my opinion. But Linux is certainly better
for other things.
midrange.com
