CMake帮助find_path find_library-我只是不明白

Question

I am trying to learn CMake. I have the Mastering CMake book and I'm trying to go through my first "easy" tutorial. Using CMake: Hello World Example

I made it through the first part alright, but when I tried to add the sub folders for the "Building a library" part of the tutorial I'm just not getting it. I followed the instructions all the way to the very end.

**We've seen an example of how to build a program. Now let's make a library as well. The library will be called "namer" and it will have a single function "getWorld" that returns the name of the nearest planet. We choose to put this library in a subdirectory called "namer" - it doesn't really matter where we put it, this is just an example.

I made it a subfolder in my HelloWorld project. Should I be making this a separate project?

**One way we can help CMake find the Namer package (which will be our namer library) is by writing a helper script called FindNamer.cmake. This is just another file written in the CMake language that pokes around in all the places our library might be hiding. Here is an example (put this in "hello/FindNamer.cmake"):

This is my FindNamer.cmake file:

   find_path(Namer_INCLUDE_DIRS world.h /usr/include "$ENV{NAMER_ROOT}")

   find_library(Namer_LIBRARIES namer /usr/lib "$ENV{NAMER_ROOT}")

   set(Namer_FOUND TRUE)

   if (NOT Namer_INCLUDE_DIRS)
     set(Namer_FOUND FALSE)
   endif (NOT Namer_INCLUDE_DIRS)

   if (NOT Namer_LIBRARIES)
     set(Namer_FOUND FALSE)
   endif (NOT Namer_LIBRARIES)

**The important parts here are the "find_path" and "find_library" commands, which look for the header file world.h and the namer library.

I followed the next instructions and at the very end the tutorial includes this:

**If we try again, configuration will still fail since the search path we gave for "find_path" and "find_library" doesn't actually include the needed files. We could copy them, or have added a hard-coded directory to find_path and find_library pointing to where the files are on our hard drive - but better, in the CMake GUI on windows or by running "ccmake ." on Linux, we can just fill in the directories there.

At this point I am completely confused (Newbie!!!!). I don't have a NamerConfig.cmake or namer-config.cmake file and I don't know what the find_path and find_library is supposed to be pointing to.

Thank you in advance for your help, Severely Confused :-(

Answer 1

I said I was a newbie. I guess I'm a little tired too! Yes, these must be in two separate projects.