Problems in creating a new vector (non-std vector)

[JLBorges]

> puts nullptr to both the pi and the element returned by vp[2]

It is best if we think of pi as an alias for the pointer stored in the vector at vp[2]. There is only one pointer, the one in the vector; which we can access through an alternative name pi.


> Would you tell me in what fields do you use it?

Here are a few examples from just one domain - telecommunications: call routing, network reliability analysis and failure prediction, network recovery after failure, dynamic network reconfiguration.

This does not mean that there are no GUI/browser/smartphone front-ends which make the facilities provided by these programs available to users, display alerts and notifications etc - there are very many of those. It is just that programmers who are considered to be experienced and competent in C++ are not given the task of writing these front-ends.

Two well-known examples of back-end C++ programs which are used through front-ends with web interfaces are Google search and Amazon's e-commerce software.


> is it possible a company employs a C++ console programmer?

Yes. As far as domain knowledge for C++ programmers are concerned, knowledge of network programming or system software tends to be more important (far more commonly required) than graphics. Almost all of the domain knowledge that is required is something that you would typically acquire after you have started on a job.

[Frank14]

Thank you for the case about the exercise.

from just one domain - telecommunications: call routing, network reliability analysis and failure prediction, network recovery after failure, dynamic network reconfiguration.

Is there a summary list on the usage of C++ console applications?
Apart from networking, I think these C++ console applications are needed for embedded systems too.

Now although I'm almost at the beginning of chapter 21 of the book PPP, I don't know how for example use these kinds of applications in these fields and also haven't been taught by the book so far.
Should I pass a course?

I guess front-ends are of graphical applications and back-ends of console ones. Is my guess right?

Almost all of the domain knowledge that is required is something that you would typically acquire after you have started on a job.

what does that mean please? Is it that I should deal with and be involved in these console programs until I find a job and then I will learn how to use them in those fields!?
But when interviewing for a job, they want me to know almost everything at the first place! :(

[MikeyBoy]

Is there a summary list on the usage of C++ console applications?

Yes. That list has the following items:

1) Absolutely everything that you would ever want a computer application to do, except for displaying information visually to the user.

There, you see - a very short list!

Seriously, I don't understand why this is a question? Can you not think of anything you would ever want a computer program for?

[Frank14]

1) Absolutely everything that you would ever want a computer application to do, except for displaying information visually to the user.

Good, thanks.

There, you see - a very short list!

Yes, I agree! :-) ;)

I got your intention, I think. And I also guess for programs that can be written by C++:
Graphical ones have their foundation/base written in console and their visual appearance using the help of a library.
Console ones have their whole code in console.
I'm still thinking of how to be skilled to use console code in the real world for a job.

[JLBorges]

> Is there a summary list on the usage of C++ console applications?

I think you are not appreciating the nature of programs that are used in real life.

Let us take an example: you go to a book shop (which is part of a chain), browse for some time and purchase three books for which you make a payment using your credit card. How many programs would be involved in processing this? In how many different machines? In how many different locations? How many of these programs would have a visual user front-end?


> what does that mean please? Is it that I should deal with and be involved in these console
> programs until I find a job and then I will learn how to use them in those fields!?

Primarily, yes. A programming language can be learnt relatively quickly. Acquiring domain expertise takes much longer; and there are very many diverse domains.

[MikeyBoy]

Let us take an example: you go to a book shop (which is part of a chain), browse for some time and purchase three books for which you make a payment using your credit card. How many programs would be involved in processing this? In how many different machines? In how many different locations? How many of these programs would have a visual user front-end?

Or, for another example even closer to home - OP, take a look at the number of processes running on your computer right now. The one you're using right now, to read this thread.

Most of those processes don't have any kind of display or GUI. They're just sitting there, quietly getting on with the business of keeping your computer running, without bothering you with a display.

[Frank14]

I see. I think if I say, most of the whole code running in our life is console, I'm not wrong.

But something annoys me. It's hard to convince, say an employer, that I know C++ console programs and also know it's used in many fields and areas but can't use it in these fields and areas.