So, we have all seen (some of you guys might have even made) professional libraries which have proper include directories which contain all the header files you need to use the library. An example would be the OpenCV library include folder which I have attached.
When we release libraries, what we do is just zip the headers for the lib and ask the recipient to extract them to somewhere convenient, which is, to be honest, quite fine. However, I would like to make an 'include' directory with all relevant headers if possible because I feel that my distribution can be organized better that way. How can we go about doing that?
You can just create a folder for all neccessary headers and specify path considering that folder when include them in code.
You can also specify that folder in preferences of your project, for example Visual Studio or Eclipse allow it, so you shouldn't write full path for those includes.
Related
I am about to start writing a code in C++ for my PhD. Until now I worked with small code. All the files (sources and headers) in one directory.
Since I want to write a more organized code, I'll put files in different directories.
So what is the proper way to include files? Should I use something like
#include "../../folder/file.hpp"
It doesn't look very clean. And is the code portable to Windows if includes are done this way?
is the code portable to Windows
I don't see a reason why it wouldn't be, as long as you fix the syntax of the directive first. I don't have a windows to test at the moment, but that's a valid path.
However, I would recommend to avoid parent directory include paths. Instead, specify a directory as an include directory for the compiler, put all your headers there into sub-directories and include with a path relative to the include directory.
I have an application where I am compiling against the libraries Qt (5.11) and Paraview (5.6). I am developing in C++ and I am also coding in Eclipse.
Yes, I am aware that Paraview is more of an application then a library. However, I will be using it as a library to intergrate Paraview in my application in order to visualize some data. I could use QT creator and that would take care of the QT library. However, I am not very familiar with QT creator as an IDE and my entire workflow has been based around eclipse. For this, I would like to utilize components that I am familiar with.
Now, as many of you know, the QT library is large, very large. So is Paraview. I could create a search path for each folder containing the header files I need in the C++ include settings. If I go in this direction, then my library search path will be long, very long. Also, there might be a situation where I need to change computers (for whatever reason), I would then need to edit the search paths for the new computer and that will take time.I had thought that I could only include the paths to the include files that I needed. And I have started to do that. However, when I compile my application, I noticed that the libraries would use include files that are located in a directory that Eclipse is not even searching in. At the end of the day, I would need to include all of the directories to which the header files are stored in.
I was wondering if there might be a better method to reference all of the files that my project needs? Both come with make files (I believe that Qt includes a QMake file?). Is there a simpler method to include all of the files instead of editing the C++ include path for eclipse? I did see an option for QMake in Eclipse, is there anything that I can do with that feature to compile to QT library with my application?
Thank you and any feedback is appreciated. Also, feel free to suggest edits or clarification so that my description is clear.
Note some good practices when working with eclipse and qt or other large library.
Include the directories with a headers
If you use option "Generate Makefile automatically", add group include path with GUI Eclipse:
copy the directories with a headers (via system explorer);
go to project properties/C/C++Build/Settings/Tool Settings/GCC C++
Compiler/Includes.
paste directories (Ctrl+V) into "Include paths" list.
If you are using a qt-eclipse-integration plugin, you can add folders via the Discovered scanner configuration. You can find it if open: project properties/C/C++ Include Paths and Symbols/Add Contributed...
Create new project
if you already have a customized project, you can use it as a template:
make a copy of the customized project and name "mytempate";
delete all files from "mytempate".
When you want to create a new project, copy the template and specify (in the copy dialog) the path where the source codes are located.
Now you have a finished new project with settings and code.
Change computers
Use one of the ways:
1. Export C/C++ project settings for use in another workspace via project properties/C/C++ General/Paths and symbols/Includes/Export Settings...
2. Pack in the archive eclipse and workspace and copy your another computer.
I know many have asked this question, but following the things suggested hasn't seemed to work for me. So I thought I'd ask for help, as I'm obviously missing something.
I've spent the past couple days writing some code that uses the boost library that allows me to open text files, translate the text into a usable data format, and save the data as a text file when I'm done with it. I built it specifically to be extendable to deal with different datatypes (specifically any object or class I make down the line) so that I could link to it as a library in my project as I do other libraries.
However, even after compiling it into a lib and adding the directory of the lib to the "Additional Include Directories", I get an unresolved external error whenever I try to include one of the header files in the library. I've also tried putting the direct path to it under Additional Dependencies (as well as just the library name with the path to the directory set in Additional Include Directories and Additional Library Directories. I also tried it with only one of those on at a time and it still failed).
Is there something I'm missing? How can I compile this code I'd like to reuse and link to it in new projects without copying the cpp and h files into my solution every time? Would a DLL work better/easier? If so, how would I go about compiling it as a dll and linking to it?
Thanks for reading this wall of text. Any help you could provide would be great.
Ok. While it's not the exact solution I was going for, I managed to figure this out. For anyone running into this problem, there's a wonderful tutorial that explains how to make DLL files and make use of them (at least on windows, don't have any computers using an alternate OS set up yet to test the DLL on). You can find it here.
http://programmingexamples.wikidot.com/blog:1
The gist of the problem is you need to also keep a copy of the .h file handy to include in your project. (what I did is created a directory on my C drive that holds the libraries I'm making, and in that I have a folder for the .lib files and a folder for the .h files.) Either import the .h file directly into your project directory or add it to your project properties (C++ -> General -> Additional Include Directories ). Make sure for that, you're linking to the directory, not the file itself. In the linker, you need to add your .lib file to the Additional Dependencies section (Linker -> Input -> Additional Dependencies). You can put the whole path here, or you can just put the file name, then tell the program where to find the directory it's in (add the path to the directory to Linker -> General -> Additional Library Directories)
Hope this helps anyone else who managed to miss something that everyone else seems to understand instinctually :P
say I have a sln which contains 10 projects(named proj1 to proj10), and proj1 is the default project which generate the EXE file.
My problem is: how to place the 'include' folder?
I mean if proj2 uses proj3(that is including its header file and linking its lib file), how to place the 'include' folder?
there are two approaches:
place all header files and lib files in a different root folder which is in the same level of the project
make every project self-close, and the other projects who want to use this project should take care of the include-path and link-path. Of cause we should give a rule to the layout of every project(e.x. every project MUST have a 'include' folder and 'lib' folder in the root folder)
any suggestion?
thanks
When it comes to Visual Studio, I don't like either of the two approaches you suggested, although mine is most closely related to your Option #2. The way I like to organise it is like this:
<SolutionRoot>
<Project1>
project1.vcxproj
someheader.h
somesource.cpp
<Project2>
<Project3>
<Project4>
<Project5>
application.sln
In case that's not obvious, that's a quasi-directory listing showing some project folders and the base solution file.
All new projects are just added to the solution using Visual Studio's default settings. Trying to go against this and making projects work like Linux projects (lib, include, src etc) just ends up causing you grief, so don't do it.
Now, I set my "additional includes" path on every project to $(SolutionDir). Then if I want to include something from Project1:
#include "Project1/someheader.h"
The advantage of this is you don't clutter up your 'additional includes', so it's easy to see at a glance what external includes a project has.
As for linking to lib files, why not take advantage of Visual Studio's project references feature. Honestly, your life will be easier. Simply hook it up so that Project2 references Project1, etc... Then you don't have to worry about libraries and linker paths. You only do that for toolkits that are outside your solution tree (eg distributions such as libpng or openssl).
Again, you free up that setting so it only shows linkages outside of the solution. The other advantage is that your build order is implicitly defined if you use references.
I would go with the 1st solution. it make the project settings simple. As the C++ projects we worked on, we always put the header files together.
for example I need to include a header
#include <OpenGL/glext.h>
while it is actually a header file glext.h under OpenGL.framework/Headers/.
Therefore it is no way to give eclipse a physical path about "OpenGL/glext.h", and I always get unresolved inclusion warning.
I can still build and run them (with managed makefile project) but it is impossible to browse the functions or definitions from those "resolved" header files.
is there any solution?
While not ideal, my solution to this has been to create a folder "/Developer/Framework Headers" (though the name isn't important), and link from e.g. "/System/Library/Frameworks/Foo.framework/Headers" to "Foo" under said folder. Then in Eclipse I add "/Developer/Framework Headers" to a project's includes.
I say not ideal because apart from having to create links for the frameworks you need and add an include to each project, Eclipse seems to have trouble in certain cases such as nested frameworks (e.g. CoreGraphics beneath ApplicationServices), but YMMV.
Yes there is one. Right click on the project in "Project Explore" window and click on the "property". In there Open "C/C++ General" column and choose "Path and symbols". Now you see all of the include library path for this project. If your using C then add the OpenGL library into GNU C, or if you use C++ then add it into GNU C++. Unfortunately you have to do this for every new project. I have been searching for a while how to do this by default but nothing really useful. Hope this help you get rid of those annoying yellow wave lines.
Since current Eclipse CDT releases don't perform sub-framework header inclusion correctly, you can avoid sub-framework problems (like those generated by the CoreServices header files) by creating symbolic links to the include directories of each sub-framework. I elaborated on this subject, which stems from danhan answer on this question, in this blog post.
In order to automate this process, I've created a Z shell script which automates this process and creates the symlink to the specified frameworks' header directory, together with the links to the include directory of each one of their sub-frameworks. The script can be found in this GitHub repository.
Hope this helps.