# How to build c++ from the command line in windows 10

- download cmake for windows and install it. https://cmake.org/download/
- download visual studio installer from https://visualstudio.microsoft.com/downloads/
- run installer and choose `Build Tools for c++`
- go make yourself a drink

The rest of all this is done from the shell and any editor

- make a junk directory somewhere and put these files into it

---
`main.cpp`
```c++
#include <iostream>
                                                                                                                                                                                                                             
int main(int argc, char **argv)
{
    std::cout << "hello world!\n";
    return 0;
}  
```
---
`CMakeLists.txt`
```cmake
cmake_minimum_required(VERSION 3.20)
project(hello)
add_executable(hello main.cpp)  
```
---
`vscmd.bat`
```bat
%comspec% /k "C:\Program Files (x86)\Microsoft Visual Studio\2022\BuildTools\Common7\Tools\VsDevCmd.bat"
```
---
- run `vscmd.bat`
> this sets up the visual studio tools paths and god knows what all. Don't read
> the batch file that gets called from this batch file, you'll go blind. Just make 
> sure the path to it is correct

- type `mkdir build`
> this is where we are going to put the build files so we don't pollute our sources

- type `cd build`
> go there

- type `cmake -G"NMake MakeFiles" ..`
> this tells cmake to generate the files that the tools need to actually build stuff.
> The two dots (..) tell cmake to look for the CMakeLists.txt file one directory up
> Now you see a whole bunch of stuff that cmake generated, one of which is a file
> called **Makefile**. This is what we need.

- type `make`
> this is running a VS tool called make that reads the files that cmake generated and finally builds the thing
> You should see hello.exe