building lib with pybind11 linking other shared lib

Question

My project reply on a SO file which I will make it by cmake installing under my project folder.And it works files when I run python setup.py install

But I install it by pip, because pip will copy the project into a tmpfile,It will be removed after installed and the SO file also be removed. Hence, when I import my project, it fails for not finding the SO file.

Of course, I can install the SO file to /usr/local/lib, but I don't want to

Anyone has idea to solve it?

Answer 1

You need to make your shared library discoverable at run time. Same rules applies as for regular C++ executable.

There are several options here (list might be incomplete):

• Place shared library along with other shared libraries (e.g. /usr/lib/)
• Add custom conf with path to shared library to /etc/ld.so.conf.d/my_lib.conf
• Set LD_LIBRARY_PATH before calling python interpreter
• Use LD_PRELOAD to run python interpreter
• Set path to shared library as RPATH attribute of pybind11 module.

I personally use the latter option: it allows me to use virtualenv freely

Answer 2

You can also take a look at auditwheel if you have a wheel package.

auditwheel repair: copies these external shared libraries into the wheel itself, and automatically modifies the appropriate RPATH entries such that these libraries will be picked up at runtime. This accomplishes a similar result as if the libraries had been statically linked without requiring changes to the build system. Packagers are advised that bundling, like static linking, may implicate copyright concerns.