CMake: Building Libraries and Executables

When building projects using CMake, it's essential to understand how executables and libraries are created. By default, CMake sets the RPATH in the build tree, allowing executables to be run from this directory. This approach simplifies the process of creating complex projects by providing a basic structure that can be easily expanded upon.

To get started with CMake, it's recommended to have boilerplate `CMakeLists.txt` files saved on your machine. These files contain essential commands for setting up projects quickly without having to memorize individual instructions.

For native builds, CMake automatically builds executables and libraries by default, with RPATH enabled. This means that libraries and executables can be easily run from the build tree. However, it's worth noting that the install tree can be copied into other places on the same machine or even transferred to another machine.

When using CMake for the first time, it may seem daunting, but don't worry – the process is straightforward once you understand the basics. To create a basic local install of your project, simply run the `install` option of the CMake command (introduced in version 3.0). This will configure and build your project using your chosen build tool.

In this tutorial, we'll cover how to create a simple executable using CMake. The first step is to open a text file with your favorite editor and name it `CMakeLists.txt`. This file serves as the entry point for CMake, telling the system where to find essential files such as headers and libraries.

Within the `CMakeLists.txt` file, you can specify commands that instruct CMake to look for specific folders or directories. For example, the command `SET(CMAKE_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/include)` tells CMake to search for a folder called `include` within the root directory of your project.

Once you've set up your `CMakeLists.txt` file, run the `cmake` executable or `cmake-gui` tool to configure and build your project. With this basic structure in place, you can start building more complex projects with ease.

In the next section of these notes, we'll explore how to install a testing framework, write tests, and use compile tests with CMake. Stay tuned for more insights into the world of CMake!

Cmake build library and executable