CMake - a cross-platform build system generator that creates Makefiles used in C++ projects

CMake is a cross-platform build system generator that creates Makefiles (or other build system files like Visual Studio project files) based on a platform-independent configuration file (CMakeLists.txt). A Makefile, on the other hand, is a build system itself, containing specific instructions for a compiler to build an executable or library. Essentially, CMake is a higher-level tool that *generates* Makefiles (or similar), while a Makefile is a lower-level, platform-specific file that *directs* the build process.

CMake is a versatile build system generator commonly used in C++ projects. Below is a simple example of a CMakeLists.txt file for a basic project:

Project Structure

MyProject/
├── CMakeLists.txt
├── src/
│   ├── main.cpp
└── include/
    └── my_header.h

Example: CMakeLists.txt

# Minimum required version of CMake
cmake_minimum_required(VERSION 3.10)

# Project name and version
project(MyProject VERSION 1.0)

# Set C++ standard
set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED True)

# Include directories
include_directories(include)

# Add the executable
add_executable(MyProject src/main.cpp)

# Add custom definitions (optional)
add_definitions(-DDEBUG)

# Include optional libraries (example)
# find_package(SomeLibrary REQUIRED)
# target_link_libraries(MyProject SomeLibrary)

Example: src/main.cpp

#include <iostream>

int main() {
    std::cout << "Hello, CMake!" << std::endl;
    return 0;
}

Example: include/my_header.h

// Example header file
#pragma once

void exampleFunction();

Build Steps

1. Navigate to the project directory:

   cd MyProject
   

2. Create a build directory:

   mkdir build && cd build
   

3. Generate build files using CMake:

   cmake ..
   

4. Compile the project:

   make
   

5. Run the executable:

   ./MyProject
   

This example sets up a basic project, specifies the C++17 standard, includes header files, and creates an executable. You can expand this setup by adding libraries, dependencies, and tests as needed.