use relative paths so CMAKE_INSTALL_PREFIX works

[PacificViking]

This helps with building packages (you can now build an RPM package without modifying the CMake files).

[3v1n0]

Not sure this is fully correct, since using this patch in debian, leads to having files being installed in /usr/usr/bin for example... 🤔

[PacificViking]

Not sure this is fully correct, since using this patch in debian, leads to having files being installed in /usr/usr/bin for example... 🤔

It's been a year since I made this issue so I may be wrong, but if your CMAKE_INSTALL_PREFIX is "/usr" this would happen. However, this means you do not intend to install anything outside of /usr, which prevents libraries from being put into /lib. Set your CMAKE_INSTALL_PREFIX to "/" or unset it and see what happens.

[SkyKuker]

Your check sets CMAKE_INSTALL_PREFIX only if it's not in the environment. If it already is, then the build system disregards your addition.

However, this means you do not intend to install anything outside of /usr, which prevents libraries from being put into /lib.

Don't know about you, but there are distros following the merged /usr approach. Debian (according to @3v1n0) does as well. So why not put udev rules into /usr/lib?

[chewi]

See #170, which uses GNUInstallDirs instead.