#CMAKE LIBRARY PATH INSTALL#
#CMAKE LIBRARY PATH FULL#
#CMAKE LIBRARY PATH WINDOWS#

#CMAKE LIBRARY PATH WINDOWS#

The question вЂњHow can I put the DLLs in a sub-directory?вЂќ gets asked often, unfortunately, Windows doesnвЂ™t provide a solution to this, meaning Windows doesnвЂ™t support the concept of RPATH at all. You can set CMAKE_SKIP_RPATH to completely ignore RPATH all together. Set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)ДЇor more details on the interaction of these commands check out the CMake RPATH Handling wiki page.

#CMAKE LIBRARY PATH INSTALL#

# which point to directories outside the build tree to the install RPATH # add the automatically determined parts of the RPATH Set(CMAKE_BUILD_WITH_INSTALL_RPATH FALSE) # when building, don't use the install RPATH already

#CMAKE LIBRARY PATH FULL#

don't skip the full RPATH for the build tree Note: DonвЂ™t forget to set MACOSX_RPATH on macOS. With the following settings you can ensure that the libraries will be found in the build tree as well when you install the targets. When MACOSX_RPATH is set on macOS, then the install names for dylibs will include as prefix.

MACOSX_RPATH вЂ“ When this property is set to TRUE, the directory portion of the install_name field of this shared library will be unless overridden by INSTALL_NAME_DIRД«y default RPATH will be used in the build tree, but cleared when installing the targets, leaving an empty RPATH.

CMAKE_INSTALL_RPATH_USE_LINK_PATH вЂ“ Add paths to linker search and installed RPATH.

CMAKE_BUILD_WITH_INSTALL_RPATH вЂ“ Use the install path for the RPATH.

CMAKE_SKIP_BUILD_RPATH вЂ“ Do not include RPATHs in the build tree.

CMAKE_SKIP_RPATH вЂ“ If true, do not add run time path information.

CMAKE_INSTALL_RPATH вЂ“ A semicolon-separated list specifying the RPATH to use in installed targets.

If you want to know more, you best check out the linked documentation or resource links at the end. I wonвЂ™t go into details about the following list of CMake variables related to RPATH. CMake offers quite a few options to refine the behavior during build tree linking and install linking, as you will see below.

RPATH can also be useful during development, as you can link libraries within the build tree relative to the executable.

To prevent old behaviors and having to deal with CMake policies, you should use CMake version >3 and judging by Repology, I would recommend a minimum of CMake 3.13.

CMake MagicДЄfter some theory letвЂ™s see how this works in practice with CMake, the defacto standard build system these days.

However macOS also provides two additional placeholders: and As an example if the executable depends on and you set the RPATH to the final search path will be fulfilling the same goal as described above for Linux. On macOS is prepended to the library path (at least when using CMake), so that when you set your custom path as RPATH, is replaced with your own path. On Linux $ORIGIN represents at runtime the location of the executable and thus if set the RPATH to for example $ORIGIN/lib/libmylib.so, your executable will look for the needed shared library relative to the executable location. For that you get $ORIGIN on Linux and / / on macOS. In a lot of cases and for maximum portability, you donвЂ™t want to specify an absolute path to the shared library, but have it relative to the executable. Unfortunately, the concept gets a bit more tricky, as there are some differences between Linux and macOS. With RPATH you can solve this issue by embedding additional search paths directly into the executable.

However, in case you want to ship the shared library file with your executable or have multiple versions installed in parallel, you need to make sure, that the library can be found at your custom location. In most cases the library would be placed in a common system library path and the executable would find it due to a predefined list of places to search. When you link a shared library ( *.so on Linux or *.dylib on macOS), your executable needs to somehow know, where to look for said library at runtime.

For those in the same boat, I want to share some of my newfound knowledge and of course also link to the resources which helped me better understand this topic. It may very well be that this is common knowledge among Linux enthusiasts, but for me, as a Windows user, it took quite a while to fully understand the concept of RPATH ( Run-time Search Path).

Cmake library path