A brief CMake readme for CS 148

You have probably struggled or will struggle with make, a build system associated with Unix. Make does its job well, but it can be quite a trial to get accustomed to its way of declaring how things get done. (Amongst other charming idiosyncrasies, it's whitespace-sensitive.) Additionally, there are many different ways to get something set up quickly and easily in make, only to have your project outgrow the way you set it up back when it was only three files in one directory.

CMake tries to get around some of make's shortcomings by providing an easy way of declaring how your project is compiled. From the cmake manpage:

CMake is a cross-platform build system generator. Projects specify their build process with platform-independent CMake listfiles included in each directory of a source tree with the name CMakeLists.txt. Users build a project by using CMake to generate a build system for a native tool on their platform.

On the CS machines, CMake builds makefiles by default. A sample session with CMake might look something like this:

1. emacs CMakeLists.txt
2. cmake .
3. make

In step 1, you edit your project's CMakeLists.txt. Basic CMakeLists.txt are provided for you in your group's Subversion repositories. They are liberally commented to show how to state which files should be built as part of your project.

In step 2, you run cmake, which reads your CMakeLists.txt and builds your makefiles. In addition to Makefile, the actual makefile, CMake generates CMakeCache.txt, cmake_install.cmake, and the directory CMakeFiles. You can ignore these.

In step 3, you run make, which reads the makefiles written by cmake and builds your project. Once you have done steps 1 and 2, you don't need to do them again unless you add or remove files from your project or decide to change how it is built in some other way (such as by changing your compiler options).

CMake's home on the Web is http://www.cmake.org/

Extensive documentation can be found at one of:

• man cmake
• http://www.cmake.org/cmake/help/cmake2.6docs.html

Special help may be found by searching the CMake mailing list archive at:

• http://www.cmake.org/pipermail/cmake/

You can also ask your TAs about problems you encounter.

What if I don't want to use CMake?

If you don't want to use CMake, you can use some other build system. We strongly recommend using one of CMake or GNU make. Do not use a build system that isn't installed on the CS machines, as your instructors will have to compile your code.

If you want to use plain-vanilla make, we have provided a basic Makefile for you in /course/cs148/asgn. You will need Makefile, Makefile.rules, and Makefile.def.