[Using CMake to organize C projects] CMake Hello World

[Foreword]
This article introduces how to use CMake to build a Hello World C project.

[CMake usage routine process]

Friends who have used CMake to build projects know that the use of CMake has the following "conventions":

 1. 在项目根目录建立一个build目录：mkdir build && cd build.（该目录用于存储编译生成的相应文件）
 2. 进入build目录，编译源码生成Makefile
 3. 确定生成Makefile成功，执行make.(或者打开生成的工程文件，如Visual Studio项目文件或者是Xcode项目文件)

【Directory Structure】

Next, I want to build a Hello World and use CMake to build according to this process.

The entire project directory structure is as follows

.
└── cmaketest
    ├── build
    ├── CMakeLists.txt
    └── hello.c

---

---

main process

Step 1: Create a new hello.c

#include <stdio.h>  
int main()  
{  
  printf("hello,this is my first using cmake project/n");  
  return 0;
}  

Step 2: Create a new CMakeLists.txt

add_executable(hello hello.c)

Step 3: Use the "conventional" method to build

1. Create a build directory under cmaketest

2. Enter the build directory, compile the source code to generate the Makefile

   cmake [options] <source path>

   So execute under buildcmake ../

   

   [phpuser@node1 build]$ cmake ../
   输出如下:
   -- The C compiler identification is GNU 4.8.5
   -- The CXX compiler identification is GNU 4.8.5
   -- Check for working C compiler: /usr/bin/cc
   -- Check for working C compiler: /usr/bin/cc -- works
   -- Detecting C compiler ABI info
   -- Detecting C compiler ABI info - done
   -- Detecting C compile features
   -- Detecting C compile features - done
   -- Check for working CXX compiler: /usr/bin/c++
   -- Check for working CXX compiler: /usr/bin/c++ -- works
   -- Detecting CXX compiler ABI info
   -- Detecting CXX compiler ABI info - done
   -- Detecting CXX compile features
   -- Detecting CXX compile features - done
   -- Configuring done
   -- Generating done
   -- Build files have been written to: /phpuser/rubbish/cmaketest/build

   At this point, view the contents of the build directory:

   [phpuser@node1 build]$ ll -a
   总用量 28
   drwxrwxr-x 3 phpuser phpuser    89 1月  30 15:10 .
   drwxrwxr-x 3 phpuser phpuser    56 1月  30 15:10 ..
   -rw-rw-r-- 1 phpuser phpuser 12617 1月  30 15:10 CMakeCache.txt
   drwxrwxr-x 5 phpuser phpuser   303 1月  30 15:10 CMakeFiles
   -rw-rw-r-- 1 phpuser phpuser  1504 1月  30 15:10 cmake_install.cmake
   -rw-rw-r-- 1 phpuser phpuser  4748 1月  30 15:10 Makefile

   You can see the generated Makefile

3. implementmake

   

   [phpuser@node1 build]$ make
   Scanning dependencies of target hello
   [ 50%] Building C object CMakeFiles/hello.dir/hello.c.o
   [100%] Linking C executable hello
   [100%] Built target hello

   Check the contents of the build directory again, you can see the generated hello file

   [phpuser@node1 build]$ ll -a
   总用量 40
   drwxrwxr-x 3 phpuser phpuser   102 1月  30 15:20 .
   drwxrwxr-x 3 phpuser phpuser    56 1月  30 15:10 ..
   -rw-rw-r-- 1 phpuser phpuser 12617 1月  30 15:10 CMakeCache.txt
   drwxrwxr-x 5 phpuser phpuser   303 1月  30 15:20 CMakeFiles
   -rw-rw-r-- 1 phpuser phpuser  1504 1月  30 15:10 cmake_install.cmake
   -rwxrwxr-x 1 phpuser phpuser  8520 1月  30 15:20 hello
   -rw-rw-r-- 1 phpuser phpuser  4748 1月  30 15:10 Makefile

4. run./hello

   [phpuser@node1 build]$ ./hello 
   hello,this is my first using cmake project

---

---

Summarize

The above is the process of using CMake to build a Hello World C++ project. You can see that using CMake is much simpler than writing Makefiles yourself. You only need to add a sentence to CMakeLists.txt:

add_executable(hello, hello.c)

That's it.

Many parameters can be configured in CMakeLists.txt, please refer to

Detailed explanation of the writing and parameters of CmakeList