CMAKE_MODULE_PATH
CMAKE_MODULE_PATH is used by CMake to identify the location of CMake modules.
It has a similar purpose to LIBRARY_PATH and CPATH. It is used to locate packages
and headers at compile time.
CMAKE_MODULE_PATH is organized as a colon-separated list.
export CMAKE_MODULE_PATH="/path1:/path2:/path3"
CMAKE_MODULE_PATH contains three paths in this example.