CMakeListstxt

CMakeLists.txt is the primary input file used by the CMake build system. It is a plain text file that contains a sequence of CMake commands describing a project’s build configuration. The file is usually located at the root of a source tree and is read by CMake to generate platform-specific build files such as Makefiles or Ninja build files. CMakeLists.txt supports multiple languages, dependencies, and targets, and is designed to be portable across Windows, macOS, and Linux.

A typical project begins with cmake_minimum_required and project commands, followed by definitions of targets created with add_executable or add_library. The file also specifies include directories, linked libraries, compiler options, and other settings. Examples of common commands include target_include_directories, target_link_libraries, and set. The language used in CMakeLists.txt is CMake’s own scripting language, and commands are usually written in uppercase, though case-insensitive.

A minimal example might look like:

cmake_minimum_required(VERSION 3.14)

project(MyApp LANGUAGES CXX)

add_executable(myapp src/main.cpp)

target_include_directories(myapp PRIVATE include)

target_link_libraries(myapp PRIVATE someLib)

Beyond basic targets, CMakeLists.txt can perform conditional logic with if, foreach, and find_package, manage dependencies with find_package, and describe installation rules with install.

Usage generally involves creating a separate build directory, running cmake pointing at the source tree, and then building with the chosen generator (for example, make or ninja). Variables use the syntax ${VAR}, and commands are executed during CMake configuration to produce the final build system.