CMAKE requires gtk+-3.0

[gekrap]

cmake fails for me with the following error:

--   No package 'gtk+-3.0' found
CMake Error at /opt/local/share/cmake-3.24/Modules/FindPkgConfig.cmake:607 (message):
  A required package was not found

The need for this package is not documented, plus on my machine (MacOS 13.0.1) I fail to install it in a way that cmakes can find it (homebrew has gtk+3, but that doesn't help)

[vincent-richard]

GTK+ is required only if you are willing to build the samples (in the "examples" directory), and actually only for the "viewer" example, in the "examples/viewer" directory. Just set VMIME_BUILD_SAMPLES to OFF.

[gekrap]

Then this should be documented in the reference install manual. (seems to be README.autotools)