Thanks for bringing that to my attention. That was changed recently and the documentation was not updated. I think the easiest way is to specify cmake -DCMAKE_INSTALL_PREFIX=<whatever directory you want the output in> then run make install (or the equivalent thereof for the particular generator you used).

Also,

i guess i need to copy the .a file (i've only dealt with .so files in the past) and move the quite big (7.3MB) ../include/rpc directory to for example /usr/include, is that correct?

It's best not to do that, and instead add the installation directory/include to your include path, as well as the lib directory to your library search paths.

thanks for the response, i think it works now.

cmake -DCMAKE_INSTALL_PREFIX=

this works except that it writes the full installation path into lib/pkgconfig/rpclib.pc, which is undesirable when installing to a temporary location for example when the result is to be included in a package archive. but it seems i can fix that with sed. i am also creating an arch linux package while i figure out the setup process which i submit to the arch user repository so users can install rpclib as a package with simple commands (aur page, package source).

i see it installs .cmake files like /usr/lib/cmake/rpclib/rpclibTargets-noconfig.cmake, not sure if that is intended.

It's best not to do that, and instead add the installation directory/include to your include path, as well as the lib directory to your library search paths.

that's good advise, much easier to uninstall.

Is it correct to assume that there is no Ubuntu package for rpclib?

@MayaPosch yes. Although it is not hard to make one with CPack. But, in my opinion it is not very useful, unless it is included in Debian (but that wouldn't happen as it is due to the bundled deps).