Writing a console-based C++ IRC-client - c++

I'm learning C++ and so I've decided to begin coding a IRC-Client.
I basically want it to be consolebased, and I've looked in to libraries such as ncurses, but I don't really know whether or not this would be the best approach.
I imagine the UI being divided into one part where whatever messages are written appear, and one part where the users input goes. Ncurses seemed to be able to do this, but now I've discovered another issue.
Because I want the message-part to be event driven (whenever somebody sends a message, this should appear in the message-part) the message-part of the UI should run independently from the input-part. Also, sockets would have to be non-blocking as well.
I've looked around on the internet and haven't found any good tutorials on this, as most are either really, really old, poorly written or simply just to long.
Anyways, my questions are, how would this be done using the ncurses and socket libraries? Are their any good C++ wrappers (one thing I've learned from reading ncurses tutorials is that OOP is really wonderful...)?

You'll probably need to use a few threads to do that, so I'd take a look at pthreads.
However, you shouldn't be afraid of long tutorials, because what you're trying to achieve is not so simple, specially if C++ is the first computer language you learn.

Using ncurses for the interface sounds like a good idea. You can do a single-threaded select-based network and terminal client -- check out Beej's guide. Alternatively, Boost.asio, single-or-multithreaded, should be a solid choice, too.

Related

what after the basic c++?

i studied basics of c++ in college, we used the book object oriented programming in c++ by robert lafore.
i studied till pointers (almost half the book) and i still feel outdated using the console and not doing something other than that (forgive me for my ignorance) i want to do windows simple apps and knowing how to employ the little i learned.
the problem is when i open a win32 project in Visual studio for example it opens a lot of stuffs and many .cpp's and .h's .
is there a way to comprehend that and walking on the right path?
the code is complicated to me and mind teasing is it suppose to be like this ?intended to be like this for beginners ? is there a reliable tutorial to introduce me to that or do i need to learn the advanced concepts of c++ like templates and virtual functions and file i\o or they are not necessery ?
thank you.
There are simpler languages to learn programming in then C++, and less complicated concepts to be mastered in simple CLI applications. In fact, using C++ to write GUI software is probably one of the hardest things to learn to do well. If you are intent on learning only visual programming, and only in C++, then I suggest trying the programming toolkit QT (http://developer.qt.nokia.com/resources/getting_started/) as you will have a window on the screen faster and more logically then nearly anything else.
Otherwise, pick nearly any interpreted (VB, Python, Ruby) or quasi-compiled (Perl, Java, C#) language and work through a command line tutorial first, as your progress will be much more likely.
Create an empty project in Visual Studio, then it won't create a bunch of .cpp and .h files that you don't care about.
After that, to learn how to write a windows application from scratch, read Programming Windows by Charles Petzold, or google a windows programming tutorial on the web.
Later, get books by Jeff Richter (Windows via C/C++) to learn more advanced windows programming concepts.
win32/Visual Studio is not a good way to learn GUI programming --Visual Studio generates too many mysterious and unreadable pieces of code and the win32 API is a C API which carries a lot baggage from from the early versions of windows.
It would be much better to use a more organised and conceptualy cleaner framework like Qt or WxWidgets to learn GUI programming.
I would actually recommend you use wxPython to learn the basics of wX and switch to the c++ interface when you have a good understanding of the widgets etc.
Most of the c++ code you need for a GUI is just boiler plate property setting and exception handling which wont teach you much and is pretty tedious.
My tip on getting a hang of windows programming:
Read The Forgers tutorial.
Instead of choosing a project with stuff in it, just choose a blank project and start from scratch, it's actually not that hard once you get the hang of it. However, a basic Win32 program consists of approximately 70-100 lines, because:
You have to set up a unique window (this includes registering your window in Windows and creating it correctly)
You have to handle all the messages that are sent to your window
You have to react to the messages that are sent to your window
Especially check out the Simple Window that TheForger created, then start fideling with the flags (dwExStyle and dwStyle) in CreateWindowEx, check out the wndProc function and see what the messages are (I think the most interesting you should focus on is WM_CREATE, WM_PAINT and WM_SIZE). Hopefully, after some time you will get a feel for what everything is and how it interacts.
It takes some time but I guess most stuff in programming does if you want to learn it. When you have your basic knowledge of a window, you should probably see how you should move on, if you should start with 3D (DirectX or OpenGL) or stay with 2D (GDI+). Or take up Qt like suggested by James Anderson, it really depends on what you want to do. But I do think that you should take that decision then and not now. StackOverflow will most likely assist if you ask what direction you should take if you know what kind of a project you want to do.
You need to start somewhere. So yes, you need to learn all those things you mentioned and then some. The then some includes writing console apps until you really understand whats going on. The only reason I can speak is because I am in a similar boat. I would say, from the sound of it, that I am probably more "advanced" than you and I still find doing some assignments/projects in the console challenging.
The problem is: Windows and stuff is complicated, you have all these events (clicks, keys, mouse stuff etc) and you are interacting heavily with the operating system. It is good that you start with console apps, because there you can focus on the actual programming, i.e., learning how to use loops, functions, classes etc.
To learn how to make windows, you should absolutely understand what classes are and how to use them, because in my opinion, all window toolkits worth learning make use of classes.
So, how does this windows stuff work? The good news: A lot of work has already been done. No need for you to re-program a "print file"-dialogue, no need to hand-draw windows with their symbols and menus etc. This is all readily available in so-called frameworks, and there is a bunch of them out there. You can use the Microsoft Foundation Classes (MFC), or Nokia's Qt or wxWidgets etc.
Google for tutorials on these, and this should get you on the way. First look around which framework looks best to you and then do the Hello World examples.
Once you gain some experience, you'll see that it isn't THAT scary. The only scary thing is the unknown that is yet to be conquered.
(A more gentle introduction would be to first do Java/Swing as I find this VERY easy, but the C++ alternatives aren't too hard, really)
Just play around visual studio if you want to get familiar with Visual studio or any IDE. VS does lots of things on behalf of you. Its interactive, select one option, look into auto generated files .h or .cpp, compile it. If you get any error google it. I myself learned this way.
For learning C++ lafore is good book to start with. The most important way of learning any language is writing lots of code. Dont get tempted to look solution in book. The best way is:
a) Read the problem properly
b) Write your logic on paper first
c) Identify interfaces
d) Convert your logic into programme
e) Compile it
f) remove the errors
g) remove all the warnings

C++ File Sending Program

So I need to introduce myself to sockets and general network programming. I consider myself fluent in C++, but I basically can build stuff with the basics of C++ (think having only a basic set of legos)
Now I really need to venture forth and expand my lego set to different pieces (pardon the lego metaphor) But socket programming/network is my next target. So I thought a simple program to write would be a file sending program.
Basically a program that you type in the IP of your friend, (he has the program too) and it asks "Would you like to receive fileXXX.yyy" If he says yes, then it proceeds to send the file.
I know i'd need to know about sockets, but what else would I need to know about? Should this be a simple program to accomplish? Any recommended tutorials I read before I dive head first?
Any additional info is helpful. Thanks. And NO this is not for school, it's just kinda something I wanna learn.
C++ preferred language.
You should get yourself the boost libraries.
There is no standard socket API for C++ but boost provides one in their ASIO library that will work on multiple platforms (as is the case with all boost libraries).
beej has a good guide for unix socket programming:
http://beej.us/guide/bgnet/
You can use the same code on a windows platform if you include the winsock library and an additional startup call
The Boost.Asio library mentioned in CashCow's answer is a fantastic cross-platform and easy to use library. Don't let the asynchronous name scare you, it can be a bit daunting at times but the documentation is straightforward and easy to understand.
The boost-asio tag is also fairly active on stack overflow.

How to use the C++ Sockets Library

I'd like to do some network socket programming in C++ and have found the C++ Sockets library.
First, is this a good way to go in C++? Normally in C, I'd use some of the stuff beej describes in his tutorial.
Second, how do I compile the examples given on the site? I can't figure it out from their installation/configuration guide. So I download the tar.gz to my Linux box, then what?
To have a specific example, how do I compile and run the DisplaySocket example?
Thanks.
EDIT: Thank you for the quick answers. A comment though. I'm not really looking into "understanding" network programming as I think I do that well enough already. I want to know if there's anything in particular to take advantage of in C++, and - if "the C++ Sockets Library" is a good choice - how to use it.
That's not "the" C++ sockets library, it's "a" C++ sockets library. Boost.asio has another (http://www.boost.org/doc/libs/1_39_0/doc/html/boost_asio.html).
(Community Wiki since I can't actually help you with your question - I've never compiled the code you ask about, so I don't know at what point you might have tripped over a problem).
Network programming would be better understood by using basic socket api (BSD or WinSock) rather than a socket library which hides most of the intricacies about sockets and their behaviour.
I would second the vote for boost::asio since it encapsulates the inversion of control model that is the current, preferred model, and appears to be standard-bound. To learn what the documentation doesn't tell you, google Douglas Schmidt and his books.
I like to use the ACE networking library when I write networking code in C++. I think it does a nice job abstracting some of the intricate details away that make network coding painful but doesn't do it to the point where it hides what is going on under the hood. It also has facilities for threading and messaging which usually are needed for any project.

What's the C++ GUI building option with the easiest learning curve - VS/Qt/wxWidgets/etc.?

I'm looking to be able to build GUI applications quickly and painlessly as possible. I'm competent (though not expert, and have no formal training) in C++, but have never used a GUI building toolkit or framework or anything. I am not a professional programmer and am totally inexperienced and ignorant when it comes to building GUI apps. Have spent hours researching trying to figure out what to do; only getting more confused and discouraged though.
Qt and wxWidgets seem like the most popular options for cross-platform apps, though cross-platform isn't necessarily all that important to me; Windows-only is fine if that means the fastest learning curve.
Qt seems cool and the Qt Creator is sweet looking with lots of good demos, except it has its own classes for everything, and I'm not overly keen on learning a bunch of stuff that's only applicable to the Qt platform itself rather than more generally. I suppose I could avoid using the Qt classes except for the GUI stuff where I have to use them, but I have no idea how wise or unwise that would be.
I was thinking Visual Studio would have the smallest learning curve, but when I open a test GUI app, I see a bunch of foreign looking stuff like carats (^) all over the place - I found online that these mean "handles", which I have trouble even understanding the definition or purpose of ("sort of like pointers but not really" is basically how I've read people define them).
I know pretty much nothing about wxWidgets, or how it compares with Qt.
So every option has a big learning curve - and ideally I'd like to know which one minimizes the time you have to spend learning the toolkit/framework itself. Since I'm likely never going to be making money from the programs I create, the time I spend learning a specific toolkit would be pretty costly. I just want to be able to make a functional program using the C++ knowledge I have, but in GUI form. At the moment it seems if I want to make a GUI app, I'd have to spend way more time learning the GUI framework I'd use than writing the functional part of the app itself.
Any input from people wiser and more experienced than me would be appreciated :)
First and foremost, start simple. There's a lot to the subject. If you are finding it hard, don't try and take it in all at once.
Most of the good GUI packages have tutorials. The best advice I can give is that you try each of them, or at least a couple of them. They are the best short introduction you can have to the library you choose and if they are any good they narrow down what you need to absorb at first. That will give you some basis for comparison, because they are each trying to do very similar things (and you will see some of them before you are done), but they have different feels. You will likely find you have a preference for one and that's the one to get serious with. It will also give you a sense of what's hard about GUI programming as separate from the particulars of one package, which, if you have only used one, you won't have seen. Personally I find this sort of knowledge very helpful, because it makes me less intimidated by particulars.
Here's a list of tutorials in one place, though you have likely seen them already:
Qt's tutorial
WxWidgets' tutorial
Gtkmm book. Not quite a tutorial, though there are lots of examples.
.NET tutorials, either for WinForms or for WPF.
Second, it sounds to me that you need to get some in depth understanding of the concepts of GUI programming, not just a particular library. Here there is no substitute for a book. I don't know all of them by a long shot, but the best of the bunch will not just teach you the details of a toolkit, they will teach you general concepts and how to use them. Here are some lists to start with though (and once you have titles, Amazon and Stack Overflow will help to pick one):
List of Qt books
WxWidgets book (PDF version)
There are tons of WPF and WinForms books. I can't make a good recommendation here unfortunately.
Third, take advantage of the design tools (Qt Creator, VS's form building and so on). Don't start by trying to read through all the code they generate: get your own small programs running first. Otherwise it's too hard to know what matters for a basic program and what doesn't. The details get lost. Once you've got the basics down though, Do use them as references to learn how to do specific effects. If you can get something to work in the design tools, then you can look at particular code they generate to be able to try on your own hand-written programs. They are very useful for intermediate learning.
I'm not overly keen on learning a bunch of stuff that's only applicable to the Qt platform itself rather than more generally.
I second the comment of GRB here: Don't worry about this. You are going to need to learn a lot specific to the toolkit no matter which toolkit you use. But you will also learn a lot that's general to GUI programming with any of the decent toolkits, because they are going to have to cover a lot of the same ground. Layouts, events, interaction between widgets/controls, understanding timers -- these will come up in any GUI toolkit you use.
However do be aware that any serious GUI package is an investment of time. You will have a much easier time learning a second package if you decide to pick one up, but every large library has its personality and much of your time will be spent learning its quirks. That is, I think, a given in dealing with any complex subject.
I suppose I could avoid using the Qt classes except for the GUI stuff where I have to use them, but I have no idea how wise or unwise that would be.
You do not need most of the non-GUI classes of Qt to use Qt's GUI properly. There are a handful of exceptions (like QVariant) which you'll need just because the GUI classes use them. I found you can learn those on a case-by-case basis.
Which is the easiest to learn is really going to depend on how you personally learn.
Personally, I've found Qt to be the easiest to learn so far. The GUI classes are rather nice to use, but I've found the non-GUI classes to be excellent, making it easy to avoid a lot of common issues you'd normally get with a more basic API. The documentation is excellent, IMO, as are the books, the examples, etc. It's also being very actively developed, with a few new technologies coming in the near future (like DeclarativeUI).
I've found Visual Studio/Windows API/.Net to be a good bit more complicated to learn. The API documentation on MSDN is rather complicated and not really organized in a manner that I find intuitive.
I've tried learning WxWidgets a few times, but I've never liked the API documentation.
All this is just my personal experience, YMMV of course. I'd say just dabble in all of them and see which one takes you the furthest, it won't hurt to try multiple.
As a person who learned C++ through Qt, I can only say that they work very well together. C++ purists (like I have become) will find lots of things in Qt not to their liking (the moc preprocessor, e.g., and the continued absence of exceptions for error reporting), but looking back, Qt provided a very gentle introduction to C++ for me.
And if you're like me, you throw in a handful of boost libs in each Qt project, because we want to write "real" C++, not the softened thing Qt uses :)
I would suggest wxWidgets. To me, it's pretty intuitive and looks nice.
Code::Blocks was built with it, so check that out to see if you like the graphics.
There are also a slew of bindings for wxWidgets, such as wxPython, wxErlang, and others, so if you decide to switch off of C++, you can take wxWidgets with you.
I also use wxWidgets and use it all the time for Windows-only applications (the only downside is that wxWidgets is notorious for large .exe filesizes, which may or may not be a problem for you). I found it very simple to use from the start, especially when combined with a GUI designer (personally I use wxDev-C++).
I've never used Qt, so I can't speak to its simplicity, but I doubt the difficulty is on a vastly different scale than that of wxWidgets. However, what I can say is that no matter what API you use (wxWidgets, Qt, WinAPI, etc) your code will be "locked into" that particular platform, so don't worry if you feel that learning Qt will lock you into the Qt platform (because the same thing will happen with any of those APIs).
If you're working solely on Windows however, you may want to do a few simple programs with WinAPI first. That way you have a basic understanding of the lowest level of Windows GUI programming before you move onto Qt/wxWidgets. That said, if you're really into cross-platform programming, then don't worry about that and go straight into Qt/wxWidgets.
I can't intelligently comment on the learning curve aspect, but a quick survey of StackOverflow questions shows about twice as many Visual C++ questions as Qt questions. Probably means that there is a larger support group in place for Visual C++. Might make learning it a little easier if there are more folks to help out.
No matter what you pick, I am quite sure it won't be easy and painless.
Having said that, I know that in some schools they use FLTK because they consider it relativelly easy to learn. I have never tried it.
In my everyday work I use WTL which is as close to the system as it gets while still providing some level of abstraction over pure Win32. I am not sure if I would consider it easy to learn, though, especially given the lack of documentation.
I recommend codegear C++ builder (previously known as borland C++ builder) from codegear which comes with a 30 trial. The nicest thing about it is that the GUI provides you with components that you drop onto a form in a WYSIWYG fashion and make functional by adding code to handle the events it fires. It comes with a whole bunch of compontents out of the box and you can add 3rd party components to it too, like the awesome ExpressQuantumGrid from devexpress, or write your own. It's very powerfull if you know what you're doing but intuitive enough that a beginner can write a database CRUD application in about 20 lines of very simple code.
Since nobody has mentioned it yet, for the sake of completeness, have a plug for the Fox toolkit. This is the one I used last time I did any C++ UI work of my own volition. There are also binding for this to Ruby and Python (the latter being many years out of date, though).
In general, the choice of a toolkit for self-directed work comes down to personal preferences for
the layout manager style
the event handler registration style
How native the widget set looks/can be made to look
If cross-platforming is not necessary, try .net + msvs or delphi. easy, all-in-one, no pain.
Qt is the best option for you. It's the easiest to learn, the most elegant and powerful and it is completely free.
Visual C++: This is an IDE, but it comes with its own GUI library called MFC. MFC is an old library with many quirks and it is difficult to learn and use. Many C++ programmers use it on Windows because it comes from MS, it's fast and it's free if you buy Visual C++. Since VC++ is an IDE, you can also use wxWidgets and Qt with it, although in your particular case I would recommend Qt Creator instead.
You seem to have experimented with Managed C++. Don't use that, even MS recommends that you only use Managed C++ as glue between C++ and C#.
wxWidgets: This one was a strong contender up to the day when Qt became free for commercial projects. It was always in the shadow of Qt and it is known that the documentation is not very good and the API is not as easy to learn as Qt's. Cross-platform MFC would be a good way to describe it.
C++ Builder: Borland made too many mistakes with C++ Builder and ended up getting out of the dev tools business altogether. It was a good product and I originally learned Windows GUI programming in one of the first versions, but I won't use it any more. There are better options and it is too expensive.

C++ developing a GUI - classes?

I do have to say I'm fairly inexperienced when it comes to C++, don't be too harsh on me.
Recently stumbled unto the wonders of the win32 API and have chosen to practice using it (I'd rather not use MFC/wxWidgets/etc at this point, just for educational purposes).
Well, my real question is:
How do you properly code your win32 GUI stuff into classes. I mean, sure, you can make a class that saves individual window handles, allows for easier modification of window properties, has a more simplified version of CreateWindow(). But as I understand it you will need a messagepump and several callback functions for your created windows. How does that work when combining them with classes?
Could anyone point me in the right direction here? I don't mind reading (a lot of) example code as long as it is commented.
PS: I'm also having trouble finding good (read: easy) documentation on using 'resource files' for my window decorations. Bonuspoints for that! :)
I program in C++ for a living. I like C++.
That said, your life will be so much easier if you do your windows GUI in something .Net, e.g., C#. Win32 is very low-level and you will be building tons of stuff that you will get for free with the .Net libraries. Win32 is not a wonder, anymore. :-)
If you want to learn C++, pick something other than a GUI to do with it.
I personally would use MFC instead of reinventing the wheel here. However, if you insist you need to have an application object that is instantiated when the program is run and contains the message loop and a mechanism for forwarding messages to the correct window objects.
That's the way MFC does it, at least. I'm not sure if the MFC source code is available for download, but if you have access to Visual C++ install disks (any version) you should be able to install the source code on your computer to review.
The biggest problem I faced back when I used the Win32 API (have since moved on to Linux and cross-platform solutions) were the callbacks. Especially the winproc one, AKA the message pump. I found this, which should be a good hint. I did what that page suggests when I rolled my own wrapper.
Look at MFC or ATL/WFC. If you want to re-invent the wheel, the best reference source for how to do so is the wheel itself, especially since the source code is readily available.
I would suggest reading Windows++ by Paul Dilascia. It takes you through the whole process of building a class library in C++ on top of the Windows API. It's written for 16-bit Windows, but all of the concepts presented in the book still apply. Plus, you can get it really cheap since it's "out of date".
And make sure you learn about message crackers (#include <windowsx.h>), they will keep you from pulling out too much hair. ;-)
The best way to learn this is to go and readCharles Petzold's original book. He does a good job of showing how to set up the base message loop and how to build statements for routing the various events to handlers. The real problem here is that by reinventing everything you are going to be spending hours and hours writing and debugging windows event hanlding code instead of writing your own application.
Unless you have a compelling reason for doing this yourself, you woudl be far better served using someone else's construct like MFC.
The only reason I see for coding all this yourself is if you want a basic understanding of how it works before you switch over to MFC or something similar. At least this way you would see how it works under the covers before you can forget it forever.
Many years ago, I developed a set of classes to encapsulate the API (various reasons why we couldn't use MFC). I learned a lot from the MFC source code.
The big key is that every window has a UserInfo data member - you can use it for whatever you want. What you'll want to use it for is the class's this pointer.
Now, the other tricky thing is that the message handler callback function cannot be a normal class member function, as Windows uses C calls and not C++. So your callbacks must be statics. However, since you've saved the class's this pointer, its just a matter of getting the class's userinfo, casting it to your class's this pointer and then calling whatever (non-static) class functions you need.
If you plan it correctly, inheritance will work well, including all of the inheritance that the windows themselves exhibit (ie, an Edit is a Control is a Window).
The only reason I would recommend not reinventing the wheel is you are neither an expert at C++ nor the Win32 API. Trying to learn two unrelated subjects at once will not be productive. If you want to become better at C++, write a library for a subject you know a lot about. If you want to learn the Win32 API, program it raw to understand how it works before creating (or using) a wrapper for it.
There is a pretty good C++ Windows API tutorial on the Reliable Software site.