Taking an Input from a C++ Gui into another C++ program - c++

I am currently developing a C++ program that does all the mathematical calculations, prints items to the screen that is scanned in by an RFID Reader, and allows the user to select a payment method. (Basically using RFID tags to replace barcodes)
I have started writing my C++ code for a keyboard entry and have no idea how to take an input from my RFID reader into my program. My RFID Reader is a DLP-RFID1 from it comes with some demo software and drivers. I got it working with windows 7 last week on the demo software(a GUI using Microsoft Visual Studio).
My question is can I take the input from my Demo GUI and some how use that as my input for my C++ program? If I can can some one push me in the right direction by links, pointers, reading material?
Also I have basic C++ experience. I am teaching myself how to program in C++ and right now only know print statements, while loops, switch/case, math functions, and etc.

That is a very specific question about hardware and software of that vendor an not really general knowledge. However, those types of devices, in my past experience with bar code readers and such, usually have a driver that comes with them which allows you to set them up as an actual keyboard (for example, you could even go into a text editor and capture the codes). If you can set them up like that, then reading them is nothing more than reading stdin. For example, cin >> stringVariable;

Assuming that you have demo software in C++:
The demo software should link against one or more libraries that comes with the demo, and include a header that declares the functions in the library. You have to (at minimum) include this header and link against that same library, and use those libraries. The demo will help you understand which functions you need to call and how.

As already said it is very dependent on how they want you to use it but some general guide lines.
Look for header file that came with their demo ( ends in ".h" or ".hpp")
you will need to #include that in your project at the very minimum
Look for a .lib file. you will need to link that to your file. With gcc you would type something like G++ -l[libname].
With MSVS there are two ways i know of. You will need to right click the project in the sidebar. Click something like options or preferences. Expand linker options. Add the library.
or you can type #pragma comment(lib, "filename.lib") in your file near your includes
If there is a .dll (windows) or .so(Linux) file you can dynamically link it. There are many ways to do this. Google search for C++ Dynamic link libraries should be some help. As a newbie try to stick with Static Linking first. that would be another good keyword to search for. The best tutorial on dynamic linking for windows i have found is actually in assembly. but its all Win32 function calls anyways so its not hard to understand. Icz DLL tutorial

Related

Is there common practice to find required header files of libraries in C++?

I am fairly new to C++ and this might sound like a very dumb question, but is there any resource or common practice to find the headers that need to be included when using C/C++ libraries?
For example: I am currently doing a project using the OpenSSL library.
How do I find out which headers I need to include for the sample codes on this page:
https://wiki.openssl.org/index.php/EVP_Key_and_Parameter_Generation
I had this issue many times and I am almost always struggling to find the right header files to include if the documentation doesn't provide a full working example.
Am I missing smoething when it comes to finding the required header files or is this lack of documentation the norm for examples?
I am aware that you were hoping to find something like a fancy database or any secret documentation to get the header.
Like for the Qt framework in the Qt Creator would be positioning the cursor on a written class in the code and just pressing alt + enter is adding the necessary header on top of the code.
Sadly that functionality is just for Qt not for c/c++ implemented.
The correct answer to your question might be as simple and maybe basic as so and it is also the fastest way I found and probably most people use:
A search engine of your choice(Google, DuckDuckgo, Startpage.com ...)
library command (f.e. EVP_PKEY)
Programming language name (f.e. c++, Qt, ...)
Proof of concept f.e. for startpage.com:
Maybe https://en.cppreference.com/w/cpp/header is an alternative - I just never found stuff real quick there.
The second best option I found and use regularly to find in addition to the header even good sample codes/examples is a program called Recoll (For Linux, Mac and Windows - or a similar desktop search engine)
Recoll is based on the very capable Xapian search engine library, for
which it provides a powerful text extraction layer and a complete, yet
easy to use, Qt graphical interface.
(https://www.lesbonscomptes.com/recoll/)
It works like that:
I put a selection of the best 50 books to a special topic in a folder (f.e. c++, c, qt - just stay really specific) and let recoll crawl the folder.
Now use keywords like EVP_PKEY to find every topic in all of your most loved and respected pdf c++ books in nano- to milliseconds - depending on how much money you spend on your pdf library. (Sure, you have to get/buy them first)
(But its a freaking fast tool and even prioritized due to the Xapian search engine library)

DBGP Implementation C/C++

Is there a Library that implements XDebug's DBGP in C/C++?
I'm interested in wrtting debugger and if such library exists will save me a lot!
I want to add the debugger to my editor coded in C++ Language but it is an editor for PHP Files.
None Exists. There was one from GSOC (App not a library) but I cannot take time to read and convert to my needs plus its written for wx2.8
So I will roll a class to Just glue up with my Editor
Edit
I ended using that one as I said.
Inside there is buggy libDBGp but I will fix it myself huh!
If you are interested its here (thanks to GitHub)
There are a few GDB based libraries that help debugger frontend writers like libgdb. DBGP is a very stupid and protocol with very small feature set - not enough for debugging C++.
For windows there is nothing like this. You can read the PDB database but it's pretty difficult. I spend a week to see how far i can get but wasn't very successfull. only the theory is easy. It might be better to write a frontend for the command line debugger windbg just like in the old days where you had to do this for GDB.

c++: program settings - boost.PropertyTree or boost.program_options?

I was looking for a solution to store program settings or options or configuration in C++. These could be settings that are exposed in a GUI and need to be saved between runs of my code.
In my search I came across boost.PropertyTree which seemed to be a good choice. I know boost is well respected code so I'm comfortable using it and so I started developing using this. Then I come across boost.program_options which seems to allow you to do the same thing but also looks more specialized for the specific use-case of program settings.
Now I'm wondering which is the most appropriate for the job? (or is there a 3rd option that is better than both)
EDIT:
fyi this is for a plugin so it will not use command line options (as in, it's not even possible).
UPDATE
I ended up sticking with boost.PropertyTree. I needed to be able to save changed options back to the INI, and I didn't see a way of doing that with boost.program_options.
Use boost::program_options. It's exactly what it's for. In one library you get command line options, environment variables options and an INI-like configuration file parser. And they're all integrated together in the Right way, so when then the user specifies the same option in more than one of these sources the library knows the Right priority order to consider.
boost::property_tree on the other hand is a more generalized library. The library parses the text stream into a uniform data model. But You need to do the real parsing -- that of making sense of the blob of data for your needs. The library doesn't know when to expect a parameter when it sees a particular option string, or to disallow specific values or types of values for a particular option.
After some digging around I think boost.PropertyTree is still the best solution because it gives me the capability to save the options after changing them from within the program which is a requirement.
There is a non-Boost possibility too. Config4Cpp is a robust, simple-to-use and comprehensively documented configuration-file parser library that I wrote. It is available at www.config4star.org.
I suggest you read Chapter 3 (Preferences for a GUI Application) of the Practical Usage Guide manual to read an overview of how Config4Cpp can do what you want. Then open the Getting Started Guide manual, and skim-read Chapters 2 and 3, and Section 7.4 (you might prefer to read the PDF version of that manual). Doing that should give you sufficient details to help you decide if Config4Cpp suits your needs better or worse than Boost.
By the way, the indicated chapters and sections of documentation are short, so they shouldn't take long to read.

C++, console Application, reading files from directory

I have a directory and I want to read all the text files in it using C++ and having windows OS also using console application
I don't know the files' names or their number
thanks in advance
Take a look at Boost.Filesystem, especially the basic_directory_iterator.
If you want the C++ and portable way, follow the solution by #Space_C0wb0y and use boost.Filesystem, otherwise, if you want to get your hands dirty with the Windows APIs, you can use the FindFirstFile/FindNextFile/FindClose functions.
You can find here an example related to them.

C++ vim IDE. Things you'd need from it

I was going to create the C++ IDE Vim extendable plugin. It is not a problem to make one which will satisfy my own needs.
This plugin was going to work with workspaces, projects and its dependencies.
This is for unix like system with gcc as c++ compiler.
So my question is what is the most important things you'd need from an IDE? Please take in account that this is Vim, where almost all, almost, is possible.
Several questions:
How often do you manage different workspaces with projects inside them and their relationships between them? What is the most annoying things in this process.
Is is necessary to recreate "project" from the Makefile?
Thanks.
Reason to create this plugin:
With a bunch of plugins and self written ones we can simulate most of things. It is ok when we work on a one big "infinitive" project.
Good when we already have a makefile or jam file. Bad when we have to create our owns, mostly by copy and paste existing.
All ctags and cscope related things have to know about list of a real project files. And we create such ones. This <project#get_list_of_files()> and many similar could be a good project api function to cooperate with an existing and the future plugins.
Cooperation with an existing makefiles can help to find out the list of the real project files and the executable name.
With plugin system inside the plugin there can be different project templates.
Above are some reasons why I will start the job. I'd like to hear your one.
There are multiple problems. Most of them are already solved by independent and generic plugins.
Regarding the definition of what is a project.
Given a set of files in a same directory, each file can be the unique file of a project -- I always have a tests/ directory where I host pet projects, or where I test the behaviour of the compiler. On the opposite, the files from a set of directories can be part of a same and very big project.
In the end, what really defines a project is a (leaf) "makefile" -- And why restrict ourselves to makefiles, what about scons, autotools, ant, (b)jam, aap? And BTW, Sun-Makefiles or GNU-Makefiles ?
Moreover, I don't see any point in having vim know the exact files in the current project. And even so, the well known project.vim plugin already does the job. Personally I use a local_vimrc plugin (I'm maintaining one, and I've seen two others on SF). With this plugin, I just have to drop a _vimrc_local.vim file in a directory, and what is defined in it (:mappings, :functions, variables, :commands, :settings, ...) will apply to each file under the directory -- I work on a big project having a dozen of subcomponents, each component live in its own directory, has its own makefile (not even named Makefile, nor with a name of the directory)
Regarding C++ code understanding
Every time we want to do something complex (refactorings like rename-function, rename-variable, generate-switch-from-current-variable-which-is-an-enum, ...), we need vim to have an understanding of C++. Most of the existing plugins rely on ctags. Unfortunately, ctags comprehension of C++ is quite limited -- I have already written a few advanced things, but I'm often stopped by the poor information provided by ctags. cscope is no better. Eventually, I think we will have to integrate an advanced tool like elsa/pork/ionk/deshydrata/....
NB: That's where, now, I concentrate most of my efforts.
Regarding Doxygen
I don't known how difficult it is to jump to the doxygen definition associated to a current token. The first difficulty is to understand what the cursor is on (I guess omnicppcomplete has already done a lot of work in this direction). The second difficulty will be to understand how doxygen generate the page name for each symbol from the code.
Opening vim at the right line of code from a doxygen page should be simple with a greasemonkey plugin.
Regarding the debugger
There is the pyclewn project for those that run vim under linux, and with gdb as debugger. Unfortunately, it does not support other debuggers like dbx.
Responses to other requirements:
When I run or debug my compiled program, I'd like the option of having a dialog pop up which asks me for the command line parameters. It should remember the last 20 or so parameters I used for the project. I do not want to have to edit the project properties for this.
My BuildToolsWrapper plugin has a g:BTW_run_parameters option (easily overridden with project/local_vimrc solutions). Adding a mapping to ask the arguments to use is really simple. (see :h inputdialog())
work with source control system
There already exist several plugins addressing this issue. This has nothing to do with C++, and it must not be addressed by a C++ suite.
debugger
source code navigation tools (now I am using http://www.vim.org/scripts/script.php?script_id=1638 plugin and ctags)
compile lib/project/one source file from ide
navigation by files in project
work with source control system
easy acces to file changes history
rename file/variable/method functions
easy access to c++ help
easy change project settings (Makefiles, jam, etc)
fast autocomplette for paths/variables/methods/parameters
smart identation for new scopes (also it will be good thing if developer will have posibility to setup identation rules)
highlighting incorrect by code convenstion identation (tabs instead spaces, spaces after ";", spaces near "(" or ")", etc)
reformating selected block by convenstion
Things I'd like in an IDE that the ones I use don't provide:
When I run or debug my compiled program, I'd like the option of having a dialog pop up which asks me for the command line parameters. It should remember the last 20 or so parameters I used for the project. I do not want to have to edit the project properties for this.
A "Tools" menu that is configurable on a per-project basis
Ability to rejig the keyboard mappings for every possible command.
Ability to produce lists of project configurations in text form
Intelligent floating (not docked) windows for debugger etc. that pop up only when I need them, stay on top and then disappear when no longer needed.
Built-in code metrics analysis so I get a list of the most complex functions in the project and can click on them to jump to the code
Built-in support for Doxygen or similar so I can click in a Doxygen document and go directly to code. Sjould also reverse navigate from code to Doxygen.
No doubt someone will now say Eclipse can do this or that, but it's too slow and bloated for me.
Adding to Neil's answer:
integration with gdb as in emacs. I know of clewn, but I don't like that I have to restart vim to restart the debugger. With clewn, vim is integrated into the debugger, but not the other way around.
Not sure if you are developing on Windows, but if you are I suggest you check out Viemu. It is a pretty good VIM extension for Visual Studio. I really like Visual Studio as an IDE (although I still think VC6 is hard to beat), so a Vim extension for VS was perfect for me. Features that I would prefer worked better in a Vim IDE are:
The Macro Recording is a bit error prone, especially with indentation. I find I can easily and often record macros in Vim while I am editing code (eg. taking an enum defn from a header and cranking out a corresponding switch statement), but found that Viemu is a bit flakey in that deptartment.
The VIM code completion picks up words in the current buffer where Viemu hooks into the VS code completion stuff. This means if I have just created a method name and I want to ctrl ] to auto complete, Vim will pick it up, but Viemu won't.
For me, it's just down to the necessities
nice integration with ctags, so you can do jump to definition
intelligent completion, that also give you the function prototype
easy way to switch between code and headers
interactive debugging with breaakpoints, but maybe
maybe folding
extra bonus points for refactoring tools like rename or extract method
I'd say stay away from defining projects - just treat the entire file branch as part of the "project" and let users have a settings file to override that default
99% of the difference in speed I see between IDE and vim users is code lookup and navigation. You need to be able to grep your source tree for a phrase (or intelligently look for the right symbol using ctags), show all the hits, and switch to that file in like two or three keystrokes.
All the other crap like repository navigation or interactive debugging is nice, but there are other ways to solve those problems. I'd say drop the interactive debugging even. Just focus on what makes IDEs good editors - have a "big picture" view of your project, instead of single file.
In fact, are there any plugins for vim that already achieve this?