CMake Documentation Reading Notes – Simple ‘Hello World’ Project

First, install gcc-g++ and cmake. Taking CentOS as an example:

yum install gcc-c++
yum install cmake

First, create a main.cpp file that includes a main function, and create a CMakeLists.txt file. The purpose of the CMakeLists.txt file is to guide CMake in compiling the C++ program on the current operating system.

main.cpp

#include <iostream>
int main(){    std::cout << "Hello World!\n";    return 0;}

CMakeLists.txt

cmake_minimum_required(VERSION 2.4)
project(hello_world)
add_executable(app main.cpp)

Analysis:

① cmake_minimum_required(VERSION 2.4): Sets the minimum required CMake version for the current script.

② project(hello_world): Starts creating a new CMake project.

③ add_executable(app main.cpp): Builds the app program using the main.cpp file.

Non-recommended build commands:

> cmake ....> cmake --build .

① cmake .: This command will look for CMakeLists.txt in the current directory and generate a build directory there.

② cmake –build .: This is the build/make command.

Recommended build commands:

This method keeps the directory cleaner.

> mkdir build
> cd build
> cmake ..
> cmake --build .