In a project I am working on I depend on a couple of external libraries that are necessary for the program to run. On my local machine they can be found in usr/local/lib and everything works like a charm.
Now, when I build my Release I want these libraries to be added to the build
(I want to end up with my executable and all necessary libs) and configure it, such that when I run the program from commandline, it knows the libraries are in lib.
I could manually add all the libraries in this folder on my local machine and configure my project so that it can find the libraries here, but, even using variables, it still inserts a local path, so using it on other machines does not work. Or is there a way to do this starting from the project path?
Is this possible using CDT?
If you use relative paths to the project folder, that should be totally portable, as long as the other machines can run such libraries. For example if your project is in /home/Fristi/project, you could just copy all your static libraries into ./libs (which actually points to /home/Fristi/project/libs and add ./libs in your makefile or CDT configuration.
Related
I'm working on a game in SFML. It runs correctly on my computer, but if I send it to another computer then when I try to run it I get errors about not being able to find libraries. I did some research and I found that the reason is because I was using dynamic libraries, and to get the program to work on its own I need the static libraries. But how do I get those? They aren't in my sfml folder. I tried doing more research but I can't find a way to build or download those libraries.
Just go to your sfml Src directory and look for the /bin folder. Copy the following DLLs to your game folder where your exe is located:
DLLs
sfml-graphics.dll
sfml-window.dll
sfml-audio.dll
sfml-network.dll
sfml-system.dll
On Linux, install libsfml-dev on target computer.
I am sure you are using mingw compiler. You can add static arguments and try.
-static-libgcc -static-libstdc++
If this doesn't work try to search the two DLL files in your standard compiler path /bin folder and place them where your exe is located.
I have an issue where I'm developing on one system where Boost is installed on:
/usr/include
/usr/lib
On a system I will deploy this on, the libboost libraries are at:
/nfs/mount/boost
/nfs/mount/lib
And I can't go about changing every system I deploy on to install libboost in the same place.
Is there a way to either:
include libboost as part of the binary executable such that loading from the system lib paths is not needed.
make the executable search for different directories when trying to load to libboost?
I'm using g++ 8
Sounds like you need a more sophisticated build environment.
I'm not sure what you mean here:
include libboost as part of the binary executable such that linking is not needed
Linking is not something you can skip. If you are trying to avoid distributing .dll/.so files with your executable, you need to avoid using the portions of the boost library that require compilation of the boost binaries (i.e. those not listed here https://www.boost.org/doc/libs/1_62_0/more/getting_started/windows.html#header-only-libraries).
Of course, that is not often the case. So...
make the executable search for different directories when trying to link to libboost?
This will never work reliably as you scale and is a nightmare in the CI world. This is where package managers such as conan (https://conan.io/) come to save the day. Delegating the package management to a third-party is the most reliable way of getting your code to build across multiple environments/platforms.
Also, building your executable and distributing it are separate operations. Any dynamically linked libraries will need to be discoverable on the system path at runtime.
I have downloaded a ROS2 demo from the examples repository.
Specifically, I have used minimal_subscriber and minimal_publisher.
I have ROS2 installed in /opt/ros2 and when I build these two examples with colcon build, it generates an install/ directory with lib/, shared/ and the other usual directory structure.
I can execute and run these demos perfectly fine with my current setup in my machine, but these executables link to libraries present in /opt/ros2, so when I want to execute them in another machine without ROS2 installed or I move my ROS2 installation in my machine, the executables cannot find the shared objects.
I've added a really simple script that adds all dependencies to install/lib when building but the executables don't seem to care, they aren't looking for shared libraries in the generated lib directory, they keep trying to search in /opt/ros2.
I believe this is something I should solve in CMake and it's not ROS2 specific, so, is there any way I can tell my generated executables to search in a diferent directory? (../lib or ./lib in my case)
If you are building them yourself (assumed since you mention CMake), you can set the RPATH in CMake (docs here). Specifically set the CMAKE_INSTALL_RPATH something like:
set(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
If you can't rebuild them, you can set LD_LIBRARY_PATH in your environment to where the libraries are located, or you can patch the executables themselves with an updated RPATH by using patchelf.
In order to get a relative RPATH rather than an absolute RPATH, use the $ORIGIN variable in your rpath spec. See "Recommendations" the the link above for more details.
I have two projects in eclipse CDT on my Mac. One is a shared library the other is a C++ project that uses the shared library. I am trying to use the shared library, and have gotten it to compile but it will not run. When i try to run it i get a image not found error.
I haven't been able to figure out how to add my library to the path directory or ld_library_path or what every other path I need to add it to so that it can be linked to at run time. I already added it as a reference in my other project which has correctly setup run time linking for me but i need help setting up run time linking.
When I try to run a program which uses another shared-link library, also I want to run the program inside the eclipse. Here is what I did:
Insert a variable environment LD_LIBRARY_PATH="where you shared lib file is" in "Run/Debug Settings" and problem solved.
I had the some problem, the solution:
Insert a variable environment DYLD_LIBRARY_PATH = ${workspace_loc:/sharedlib/Debug} into run configuration.
In the project I am working on, we provide the possibility to dynamically load additional features. For that we use dlopen.
To find this libraries we have something we call module path. There we have a default path, where the shared libraries are (a lot of them are shipped).
At the moment we have two default paths: we first look in the build directory for the shared library and afterwards in the install directory. This is because it should also be possible to run the application without installing it (so in that case it needs to look first in the build directory).
Now the problem ist, if a user builds the application from source and installs it with make install, the libraries in her build directory are loaded by default. This will result in a crash. So it only works if the user afterwards removes or renames the build directory.
No the question: is there a trick (either by C++ or by the build system) to know whether the application is installed or not. The problem is, that the functionality is implemented in a shared library and the implemented way to search for modules has to work also for other applications that link against our library (so we can not rely on the path of the executable). We use CMake as a build system.
To make the situation even harder, the solution has to work on Windows, Linux and Mac OS X.
EDIT:
I further investigated and the problem is more complicated. This is the situation:
There is a small executable a
Furthermore there is a "main" library main.so
then there is a dynamically loaded library lib.so
lib.so links against main.so
The problem is, that lib.so has the absolute path to main.so in the build directory in its rpath. Thanks to the tip of #MSalters I now was able to make a hack to make sure to load the correct version of lib.so (the one in the install directory) but since it has the build path in the rpath it loads the wrong main.so (so in fact there are two copies of main.so in the memory - this messes things up).
Is there a way to remove this reference to the build path from the library? I tried all options of cmake related to rpath without success
Can't you check where the executable itself is? If it's in the build directories, use build libraries -- if it's in the install, use install?
getcwd() has equivalents on all of those platforms, but it might not be what you want -- it depends on how you run the executable.
To get the process's location is system specific, I think, but it shouldn't be too hard to wrap that.
The installed version should not have the build directory in the rpath.
You might want to do the linking twice (once for the build version and once for the installed version). Usually, on *nix systems, the installed binary has some static path where it tries to find plugins. You might define some environment variable (or command-line argument) to overload it for the build execution (and use a wrapper script to set it in the build environment).
Check how it is solved by some projects (Firefox for example).
I don't know much about windows system but I think the standard way of doing this is to search plugins in the same directory as the executable.