I'm wondering if there are any simple ways to link boost libraries (all or individual) via some entry like....
-lSDL_ttf
The above links SDL's True Type Font library. Can this be done with boost? If so, I'm not sure what file I'm linking for to link. I'm currently using boost_1_40_0.
If this isn't possible, or there are better ways to do this, I'd be happy to hear them.
P.S. I'm using the CodeBlocks IDE.
Most boost libraries don't need to be linked as they are header only.
For those that are not header only, see the instructions here on the naming conventions and make sure you put the folder containing the boost libraries in your library search path if you want to avoid specifying it explicitly.
For Xcode 7, A few updates to this post:
a. Following installation instructions the following link, I placed the zipped file in /usr/local, resulting in an installation directory of:
/usr/local/boost_1_60_0
http://www.boost.org/doc/libs/1_60_0/more/getting_started/unix-variants.html
b. As stated on the above page, many of the Boost libraries are "header only." In other words, there is no library, and you don't have to link the libraries; there is nothing to link! If you try and link them, you will get an error! You just have to specify the header location, like so:
Of course, if you're using a Boost library that must be compiled, you may have to link it differently, but it's important to keep this in mind.
c. Be sure to check the permissions on the installation directory. I installed as root, and had to do a chmod 755 on the install, as show below. If permission are not set, you will get the generic and utterly unhelpful "library not found" error.
Related
I am building a C++ project on my Ubuntu 64bit system using a provided Makefile, and this project also provides an API library for developers.
The compilation was successful, no errors at all, but when I try to include in my files the API libraries provided in the "api" folder, then g++ complains about undefined references.
It is not a problem about dependencies (I already built the project succesfully), in fact the missing references are about classes and functions provided by the project, but they are in some specific (sub-)folders (I don't know which ones!), I guess in some .so files, and g++ is not finding them, probably because it does not know they are in those specific subfolders.
It is not the first time this happens when trying to use APIs from any project, then I think I am missing something or I am doing something wrong in general when trying to use the libraries provided in a project.
In particular, the main problem is that I don't know how to tell the compiler where some classes or data structures are declared, and moreover I don't know how to locate them in order to know where they are.
Usually, a workaround I use to avoid this problem is to run make install (as root or using sudo) so that libraries and APIs are installed in standard folders (like /usr/include or /usr/lib) and if I do this thend I can include the API libraries using #include <library>, but in this last case it didn't work either, because perhaps some required files containing the not found classes/structures are not properly installed in the right folders in the system.
Another workaround I used sometimes is to try to put all the project files in the same folder instead of using the project folder structure, but clearly this is not good! :-)
But I noticed that several other people managed to use the APIs, then apparently they know some way of finding the files containing the "undefined" references and including them in the compilation.
Then my general question is: given a "classic" C++ project based on "Makefile" files and with usual folder names like src, lib, build, bin, etc., if I want to write C++ files using the libraries provided by the project, but the compiler complains about undefined references, how can I find the files (.so or .o or .cpp) containing such references? Is there any tool to find them? And how can I tell the compiler where they are? Should I use some command-line option for g++ or should I use the #include macro in some smart way?
PS I also tried to use the pkc-config linux tool to get right options to use for compilation and they were available, but the compiler still complains about the undefined references.
Some more degails about the project i tried:
For interested people a link to the project is below:
https://github.com/dreal/dreal3
And instructions on how to build it:
http://dreal.github.io/download/
Look into the -rpath linker option - specifically with the "$ORIGIN" argument. That lets you find libraries relative to your executable location so you don't have to install them to the standard locations but just need to put them somewhere known, relative to the executable. That should help you with one piece of the puzzle.
Note: -Wl, can be used to pass arguments to the linker via g++.
As for pointing the compiler/linker at a library so it can resolve undefined references by using that library, use the -l (that's lowercase L) option to specify the library name and -L to specify directories to search for libraries.
As for looking into a library (.so) file to see what symbols are in there, you have a few tools at your disposal: objdump, nm, readelf and objcopy.
I'm trying to build my VS2012 C++ project using Boost Regex library. It seems that the linker does not find the library and gives the error:
error LNK1104: cannot open file 'libboost_regex-vc110-mt-gd-1_50.lib'
In "Project Properties:Linker:General:Additional Library Directories", I included a path which (within a subdirectory) contains a library named boost_regex.lib.
This was built by a 3rd party framework (FireBreath), and I shouldn't change it. How do I get VS2012 to use this library instead of looking for one under the name referenced in the error?
Firstly, what makes you so sure that the boost_regex.lib is the right one? Is it even for your compiler and version? I also doubt that it is for the debug variant of the runtime library. My guess is that you will have to build this for the compiler that you're using and properly install it, for which there are instructions at the Boost website. This might also imply rebuilding FireBreath for your compiler, assuming that's a C++ library, too.
Then, the code in Boost that detects compiler settings and then selects a library to link against is correct for normal setups. This code uses "#pragma comment(lib, ...)" to specify the lib to link with, so you should be able to find the code. There, you should also be able to detect the macros that turn this feature off. However, you are probably not fixing anything with that but rather you are creating more problems.
Substituting the library is not something you want to do. Instead:
Download Boost into, say, c:\boost
Open a VS command prompt, go into c:\boost and run bjam. When this is done, run b2. Wait.
Now go into your project and add c:\boost\stage\lib to the Additional Library Directories setting.
This will allow you to build the project.
I'm totally spinning my wheels with getting a couple of 3rd party libraries to work with my c++ programs. I'm looking for some general advice (40,000 foot level) about the general steps that one needs to take when implementing libraries.
First, some specifics: I am using code::blocks in Windows as my IDE. I like this IDE and really don't want to switch to anything else if I don't have to (I've tried visual c++ and also some things in linux). The libraries that I am trying to use are GMP and crypto++.
OK. What I think I know is this: After downloading the library, I unzip the file to a folder. I've been unzipping directly to C:\ with each zip file extracted to its own folder (e.g. c:\cryptopp and c:\gmp). I think that the next step is to build the library, but this is where I get totally stuck. How is this done? There are no executable files among those extracted. From what I can tell, I believe that I do this in code::blocks, but I have no idea how?
Finally, assuming that I can get this done, which I believe creates the .lib files, the last step before actually using the library in my code, is to link into the library. This part, I believe that I understand.
So, my question is broad: do I understand this process overall? And if so, how do I go about building these libraries, if in fact that it the thing that I am missing.
Thanks very much for indulging my ignorance. I'm totally rudderless right now and despite hours and hours on google, I'm making no progress. Also, feel free to correct anything that I have stated as fact that is not correct. Thanks a lot!
Usually libraries have a special file called makefile in them, and are built with a utility called Make (or one of it's variations, whatever works uder windows).
Usually all you have to do is to run Make in the directory where you have unpacked the source files, and it will do the rest itself.
If those libraries you mention (GMP and crypto++; disclaimer: I'm not familiar with either of them) don't have project files for code::blocks then you may still be able to compile them under Windows with MinGW.
If you have installed MinGW you use the MinGW shell to navigate to the appropriate directories which would be /c/cryptopp/ and /c/gmp in your examples - The MinGW shell works like a Unix shell, and has different naming conventions.
Then you need to compile the libraries. Check whether there's a Makefile in those directories, if there isn't you can check whether there's a configure script, which will generate the Makefile. If you have the Makefile you can type make which will compile the libraries with MinGW's port of the GCC compiler.
When the compilation is complete you should have a library in the form of a .a file (say libcryptopp.a) that you can link to your project. In code::blocks you would set the linker path (the -L command line option in GCC) to C:\cryptopp\bin or wherever the library has been compiled, and then add libcryptopp.a to the list of libraries you want to link (this is associated with the -l option in GCC). The convention is to leave out the lib prefix and the .a extension, so you would just add cryptopp to your library list. In the end your linker options should look like -LC:\cryptopp\bin -lcryptopp along with the
Also, to be able to use the libraries you need to add the path to the headers directory to the include path of your project. This is associated to the -I command line option in GCC, so your compiler's command line options would have something like -IC:\cryptopp\include somewhere.
Of course, all of the above assumes that you use code::blocks with GCC. If you're using it with VisualC++ then the principles are the same, but the specific steps differ.
I have just downloaded the boost libraries from the boost website and extracted them to my desktop. I was hoping to just have a quick look at them and have them installed on my machine and perhaps use them in the future when I am more accustomed to C++.
When I extracted it, I was confused with all of the extracted files. There is all of the headers in the boost directory but tutorials mention running bootstrap.bat (I'm using Windows).
So I am asking this: do I simply extract the headers to my compilers include directory like normal to get boost up and running or do I need to do something else?
As I understand it from searching about, apparently "most" of boost is just templates and can be used simply by including the headers, but what about the rest?
Am I totally barking up the wrong tree?
Thanks for any help
Since you mentioned you run Windows, take a look at this automated installer:
► http://www.boostpro.com/download/
Also, some general advice:
do I simply extract the headers to my compilers include directory
No! Do not pollute your compiler's includes with third-party includes; make a separate directory specifically for a particular library. You'll then need to tell your specific IDE in what directory it can find the library headers.
I usually use boostpro's installer, it is less work. I vaguely remember having to set up the BOOST_ROOT environment variable on one of my systems to use it.
The libraries that contained compiled source should be included in the installer.
If you don't use the installer (or don't set up your build correctly), and try to use the libraries that need it you will likely get some linker errors when you try and compile your program. Usually if you take those linker errors and plop them in google it tells you pretty quick which libraries you need to include in your build system. I use CMake for that and have been very happy..
Just add the root boost directory to include paths of your compiler/IDE (so if you have Boost extracted to C:\Boost, the compiler will use that path, not C:\Boost\boost).
Don't do any copying of the boost folder to your compiler's include directory, because it may make upgrading Boost harder in the future.
Also if you plan to use any of boost's compiled libraries, add Boost's lib directory to compiler's library search paths. Configuring the compiling step is a matter of putting the right toolset parameter to boost's build tool. If you have your command line environment configured properly, bootstrap should run and compile the builder without any problems, and the Boost builder should properly detect your toolset, so no parameters will be necessary.
As you do such configuration only once every time you do a clean install of your favorite compiler, it's not as hard or daunting as it seems.
I've been trying to get the boost library working with Code::Blocks and am having some trouble.
When I first tried to get boost, all I did was download the latest zip file and extract it into the CodeBlocks folder. Then I set the compiler settings to look in the boost folder. This allowed me to compile, but not to link. I then read the BoostWindowsQuickReference. I removed everything I had related to boost from my machine, and started fresh.
I followed the instructions step by step, and the only thing that didn't go exactly as the instructions said was that the install-proper folder with the include\boost inside of it was in C: and not my CodeBlocks folder. So I simply copied it (just in case for some reason it needed to be there) to the CodeBlocks folder, which I thought odd because I already had a boost_1_40_0 folder there from downloading the .zip.
I then tried to compile a program and it came up with the exact same error. Then I realized that I forgot to put in the link library (Ex: boost_regex-mgw44-mt-1_40.lib). Now I get
error: ld.exe||cannot find -lboost_regex-mgw44-mt-1_40.lib|
I have a few questions:
Obviously, what am I doing wrong?
Will I need to put in a link library every time I want to use a boost facility (everything is separated into different files, there isn't just one big project.)
Was it necessary to build the library with the boost-jam or could I have just extracted it and used it? (Probably a dumb question, but a small seed of doubt was planted when I got the exact same error.)
Should I try nuwen's MinGW Distro? (Would it make things any easier?)
If any clarification is needed I'd be happy to do so. Thanks.
Edit: and now I can't compile regular programs. So I'm just starting fresh again.
1, it should be -lboost_regex-mgw44-mt-1_40
2, Read the document, most boost library doesn't require to link library
3,4, You should compile it yourself, or try nuwen's MinGW ( I'd installed it and it worked fine )
BoostPro has Windows binaries available for the Boost libraries. If you download just the Boost sources, you will have to compile it, if you are using any of the libraries that are not header-only (such as boost regex). The BoostPro binaries will allow you to link to these without having to build anything.
On Windows it doesn't really matter where you "install" Boost to. Just get the .7z, compile using bjam.exe and pass it the options you need. It will create a folder called "bin.v2" and put the resulting libs in there. In Code::Blocks, all you need to do is edit the project options and point the search path to boost_1_40_0\boost and manually input the libraries to link against (those from bin.v2). It should just work then.
Do not use a precompiled Boost library.