【CPP】CMake

Examples

main.cpp

#include 
#include "functions.h"
using namespace std;

int main()
{
    printhello();

    cout << "This is main:" << endl;
    cout << "The factorial of 5 is: " << factorial(5) << endl;
    return 0;
}

factorial.cpp

#include "functions.h"

int factorial(int n)
{
    if (n == 1)
        return 1;
    else
        return n * factorial(n - 1);
}

printhello.cpp

#include 
#include "functions.h"

using namespace std;

void printhello()
{
    int i;
    cout << "Hello World!" << endl;
}

functions.h

#ifndef _FUNCTIONS_H_
#define _FUNCTIONS_H_
void printhello();
int factorial(int n);
#endif

CMake

What is CMake

CMake is an open-source, cross-platform family of tools designed to build, test and package software. CMake is used to control the software compilation process using simple platform and compiler independent configuration files, and generate native makefiles and workspaces that can be used in the compiler environment of your choice.

CMake needs CMakeLists.txt to run properly.
A CMakeLists.txt consists of commands , comments and spaces.

• The commands include command name, brackets and parameters ,
  the parameters are separated by spaces. Commands are not case sensitive.
• Comments begins with ‘#’.

A single source file in a project

CMakeList.txt

cmake_minimum_required(VERSION 3.10)

project(hello)

add_executable(hello main.cpp factorial.cpp printhello.cpp)

cmake .

生成了cmake_install.cmake, CMakeCache.txt, Makefile 三个文件
以及一个文件夹 CMakeFiles

编译：

make

生成hello可执行文件

./hello

make clean

删掉了hello文件

但是还有其他文件没有删掉，需手动删除。

所以建议在CMake之前就新建一个build文件夹，在build文件夹里进行cmake

mkdir build
cd build
cmake ..

附录

生成的Makefile是这样的：

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