Recently, I'm studying Bazel following the tutorial in http://www.bazel.io/docs/tutorial. I have known the usage of BUILD files, but I'm still confused about the usage of files having a .BUILD suffix, e.g. when they are involved in the building process, what their syntax is and what the differences are between them and BUILD files (though they look similar). Since I cannot find any documents introducing ".BUILD" files either on above link or by googling, could anyone explain the usage of ".BUILD" files to me, or provide me some references? Thanks in advance!
The documentation about Bazel concepts is at http://www.bazel.io/docs/build-ref.html and the part on BUILD files is at http://www.bazel.io/docs/build-ref.html#BUILD_files
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I've used C++ for several courses in university but the libraries we used in these courses were quite simple to install. When we came across libraries which required a bit more complex installation, our teachers always provided detailed instructions.
This time I'm doing a project on my own. I have downloaded libraries for my own projects in the past. Sometimes the install was easier, sometimes I had to search for hours to do things most people here would do in 5 minutes.
I did some studying to remember some stuff about the compiling process, what dynamic and static libraries are, etc. I feel I understand the most part but it didn't really help me with my efforts to install some libraries. Some people in Github provide instructions for newbies like me, but others, understandably, don't.
I'm saying a lot so I'll get to the point. I will provide links for the library I'm trying to install but in case I'm not allowed to, please let me know so I can rewrite this in a way that is allowed.
I'm trying to install libccd so I can then install fcl. In the instructions 3 ways are mentioned:
Using Makefile
Using autotools
Using Cmake
In all 3 methods, I see specific commands like this :
First of all, where am I supposed to write these commands?
I don't even know how to search this. So, I tried installing with methods I've previously used.
Here are the steps I took:
Downloaded the whole repository.
Made a solution for Visual Studio with Cmake-gui (that's all I know how to do with Cmake,unfortunately it usually was enough so I never learnt more)
Compiled the code in Release mode, which should give me a lib file.
Now,in my own project, I added the relevant include directories of the repository I downloaded and the library directory for the lib file which was produced.
I'm not sure about my last step. I'm pretty sure if I did the installation as proposed in the link(and as required by fcl), I would have a new folder for the library including just an include folder and a lib folder. Now I'm just searching for the correct include files and the lib file in subfolders of subfolders hoping I include the right ones. I'm a bit lost.
I'd really like some general steps(if there are) to installing a library. I know each library has its own ways but I assume the general idea with Cmake or Makefile should be the same. I have tried searching online but I didn't come across a good or detailed enough tutorial. I really don't wanna waste any more days trying to install libraries and I don't want to end up asking here again.
UPDATE:
It looks like there is no standard way to install libraries. Since I'm getting 'close votes' I'll include a specific question:
Are the steps I took correct? What should I do next?
I'm trying to install libccd so I can then install fcl. In the instructions 3 ways are mentioned:
Using Makefile
Using autotools
Using Cmake
In all 3 methods, I see specific commands like this :
First of all, where am I supposed to write these commands?
These instructions are for a UNIX-like system. Makefiles, autotools... these are UNIX things. You'd typically write those build commands into a console window on something like Linux or a Mac.
CMake is a bit more cross-platform. You can find out how to invoke CMake on other SO questions.
You can get Makefiles and such to work on Windows, using projects like Cygwin and MSYS. I'd generally recommend you avoid that unless you really need it.
I'm not sure about my last step. I'm pretty sure if I did the installation as proposed in the link(and as required by fcl), I would have a new folder for the library including just an include folder and a lib folder. Now I'm just searching for the correct include files and the lib file in subfolders of subfolders hoping I include the right ones. I'm a bit lost.
This is where no "general" advice exists. Different authors put their output in different places. If their instructions didn't include this information, you're already doing the right thing. If you get really stuck, you can always just ask them.
I'd really like some general steps(if there are) to installing a library.
No such thing exists, but where these industry-standard tools are involved, you can usually go on general documentation for those tools, or from memory.
I also suggest you shop around for a general book on programming, as general principles should be covered in any good one of those.
My C++ project includes a Bison parser. What is the scons function to call for building from ".l" and ".y" files (or alike)? By build I only mean compiling the grammar into source code.
I assume that building from lex/yacc files are natively supported, but I'm curious as to what would one need to do if one has to also build some files with an 'uncommon' compiler, say a DSL compiler for that specific project.
If you want to "teach" SCons how to process a new filetype, all you basically have to do is copying the command-line. Then you put this command into a so-called Builder, which will execute the required action at runtime and will care about the dependencies for you.
For a more detailed description of solutions to this problem, which actually depend on what exactly you want to accomplish, please have a look at our ToolsForFools guide.
First, i know that make is used for building the code. But which code?
But what does it mean by building a code, and after executing the make command, what is presented to the user?
Second, how is it different from make build_for_e2e?
What Wikipedia tells about make
Make is a build automation tool that automatically builds executable programs and libraries from source code
Compilation process becomes big and complex in big projects, where numbers of files need to be compiled, with flags and libraries. Where it will become hard for people to compile it one by one. So these types of tools were introduced, there are more similar tools available for same use like cmake, gradle, maven. e2e's Build is also a form of build process, with different form of specifications.
For C people mostly use make. It is helpful for porting software packages in different systems.
How make is used:
As said make is a tool, which will be available in our system, we can execute it by giving command make in the directory which needs to be compiled. Then make looks for Makefile, which is provided in the package directory and it contains information about compilation of the project. Then make as per info gathered from Makefile, it compiles the package.
You can also create Makefile for your project, so that it can be also supported and compiled with make. Simple tutorial for it can be found here. For big projects you can use gnu autotools contains autoconf and automake which will help you to create your all files required by make automatically. You can find tutorial regarding it here and here . These contains some basic information, you can find some advance tutorial regarding autotools, use google for more information on it.
I am trying to use gnuplot++, but this is really a more general question about downloaded source code. I have downloaded the gnuplot++ source code and it consists of multiple .h and .cc files. I would like to use it in othercopy projects in the future so I am reluctant to add all the files into my project directory.
From what I understand gcc will look in /usr/local/include for header files, so I have put the code there for now. But what is the best way to compile and link the code?
Should I use the makefile to include the directory of the source code?
Should I keep it somewhere easy to find like /usr/local/include?
How do I know the best way to compile the code in gnuplot++?
Typically, if the project itself doesn't come with install instructions, I usually add it somewhere "public", e.g. /usr/local/project/{lib,include,src,...} where "project" in this case would be gnuplot++.
In this case, there doesn't appear to be any support for building this into a library, which makes it a little more awkward, as you need the sources included in your project itself. I'd still keep those sources separate, but you may prefer to just put them into a separate directory within the project [or spend an hour or three making a library of it].
For general practice, yes, keep the source for gnuplot++ (or any other similar 3rd-party project) separate from your own application source code. This makes it much easier to manage updates to the 3rd party projects, etc.
Yes, I would use the makefile for your application to also include the path to the headers for gnuplot++ and I would not copy those files directly into /usr/local/include. Instead, I would consider a couple options: do nothing and point your include path in your makefile to the gnuplot++ directory, or put symbolic links in /usr/local/include to point to the gnuplot++ files.
As for the best way to compile gnuplot++, I would have to look at gnuplot++ myself and see what it has to say, perhaps in a README file or similar.
In general, when using third-party libraries, you build and install those libraries according to the installation description that comes with the downloaded source.
If there is no installation guideline, it is typically a set of steps like
./configure
make
make install
Then it is the responsibility of the library to ensure the relevant headers and library files are easily locatable for use in your project.
gnuplot++ is an exception here, because it does not seem to come with its own build structure.
The best advice in cases such as this is to put the source from gnuplot++ in a directory within your project (possibly parallel to your own sources) and include the files in your own build setup.
I'm working on a project using C++, Boost, and Qt. I understand how to compress single files and bytestreams using, for example, the qCompress() function in Qt.
How do I zip a directory of multiple files, including subdirectories? I am looking for a cross-platform (Mac, Win, Linux) solution; I'd prefer not to fire off a bunch of new processes.
Is there a standard way to combine bytestreams from multiple files into a zipped archive, or maybe there is a convenience function or method that would be available in the Boost iostream library?
Many thanks for the assistance.
Update: The QuaZip library looks really great. There is an example in the download package (in the "tests" dir) that shows very clearly how to zip up a directory of files.
Update 2: After completing this task on my Linux build environment, I discovered that QuaZip doesn't work at all with the Visual Studio compiler. It may be possible to tackle all those compiler errors, but a word of caution to anyone looking down this path.
I have found the following two libraries:
ZipIOS++. Seems to be "pure" C++. They don't list Windows explicitly as a supported platform. So i think you should try your luck yourself.
QuaZIP. Based on Qt4. Actually looks nice. They list Windows explicitly (Using mingw). Apparently, it is a C++ wrapper for [this] library.
Ah, and of course, i have ripped those sites from this Qt Mailinglist question about Zipping/Unzipping of directories :)
Just for the record...
Today, I needed to do something very similar in Visual C++. (Though wanted to maintain the possibility to compile the project on other platforms; however preferred not to adopt Qt just for this purpose.)
Ended up using the Minizip library. It is written in plain C, but devising a simple C++ wrapper around it was a breeze, and the end result works great, at least for my purposes.
I have built a wrapper around minizip adding some features that I needed and making it nicer to use it. Is does use the latest c++11 and is developed using Visual Studio 2013, so it should work out-of-the-box for you.
There's a full description here: https://github.com/sebastiandev/zipper
you can zip entire folders, streams, vectors, etc. Also a nice feature is doing everything entirely in memory.
Poco::Zip is also a choice, it has clearly documentation and some code for demo.
Poco::Zip Document
system("zip myarchive.zip *");
I tried QuaZIP 0.4.3 on Windows with VisualStudio 2010 -- there are still issues but can be resolved easily.
To build with VS:
Use CMake to configure and generate VS solution for QuaZIP.
Open soltion with VS and build -- you'll first notice that it can't find 'zlib.h'.
Open preferences for quazip project and add path to Qt's copy of Zlib to C/C++->General->Additional Include Directories: $(QTDIR)/src/3rdparty/zlib.
Rebuild again and you'll get lots of warnings and one error C2491: dllimport static issue on QuaZipFile::staticMetaObject.
This is because QuaZipFile is declared like "class QUAZIP_EXPORT QuaZipFile" and QUAZIP_EXPORT needs to resolve to Q_DECL_EXPORT for dll and to Q_DECL_IMPORT for application, based on whether QUAZIP_BUILD is defined or not. When building QuaZIP QUAZIP_BUILD should be defined but isn't -- configuration process defines in error completely useless "quazip_EXPORTS" instead.
To fix, just remove "quazip_EXPORTS" from all build configurations and add QUAZIP_BUILD instead -- QuaZIP will now build fine.