# binary tree
**URL:** https://discourse.cmake.org/t/binary-tree/5009
**Category:** Usage
**Tags:** os:windows, gen:ninja
**Created:** [February 15, 2022, 7:16am UTC](https://discourse.cmake.org/t/binary-tree/5009 "2022-02-15T07:16:37Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@alice](https://discourse.cmake.org/u/alice)
#### Post date: [February 15, 2022, 7:16am UTC](https://discourse.cmake.org/t/binary-tree/5009/1 "2022-02-15T07:16:37Z")
[https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#build-a-project](https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#build-a-project)
What is the already-generated project binary tree?
Here is the introduction for source tree and build tree
[https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#introduction-to-cmake-buildsystems](https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#introduction-to-cmake-buildsystems)
---
### Author:  [@fenrir](https://discourse.cmake.org/u/fenrir)
#### Post date: [February 15, 2022, 7:53am UTC](https://discourse.cmake.org/t/binary-tree/5009/2 "2022-02-15T07:53:32Z")
If you just use the `cmake` command, the configuration and generation are all in one step and you don’t have to think about it.
cmake-gui allows to separate those two and configure project without generating the build system files (makefiles, ninja.build, etc). You cannot build until the generate step is done.
---
### Author:  [@hex](https://discourse.cmake.org/u/hex)
#### Post date: [February 15, 2022, 5:15pm UTC](https://discourse.cmake.org/t/binary-tree/5009/3 "2022-02-15T17:15:13Z")
CMake is typically used in project mode hence the emphasis on _project_. This command will fail if you haven’t generated a CMake project first, so already-generated is a pre-condition. To use CMake you need 2 commands:
```auto
# the project binary directory
cd build
# Generate a Project Buildsystem
cmake ..
# Build a Project
cmake --build .
```
The binary directory is any directory that you chose for CMake to use when generating the project. The binary directory is also known as build tree. Personally, i would avoid calling it a binary tree since that is more commonly known as a data structure.
---
### Author:  [@alice](https://discourse.cmake.org/u/alice)
#### Post date: [February 16, 2022, 2:40am UTC](https://discourse.cmake.org/t/binary-tree/5009/4 "2022-02-16T02:40:28Z")
How can I know the build tool for these commands on windows?
I expect `Visual Studio 16 2019` Generators
```auto
# the project binary directory
cd build
# Generate a Project Buildsystem
cmake ..
# Build a Project
cmake --build .
```
REF
[https://cmake.org/cmake/help/v3.23/manual/cmake-generators.7.html#ide-build-tool-generators](https://cmake.org/cmake/help/v3.23/manual/cmake-generators.7.html#ide-build-tool-generators)
---
### Author:  [@hex](https://discourse.cmake.org/u/hex)
#### Post date: [February 16, 2022, 11:08am UTC](https://discourse.cmake.org/t/binary-tree/5009/5 "2022-02-16T11:08:27Z")
The generators available for CMake depend on your machine. For example, Visual Studio must be installed in order to use it with CMake. You can see a list of available generators with
```sh
cmake --help
```
> [@alice](#):
>
> I expect `Visual Studio 16 2019` Generators
You would expect the one marked default in the command above. You can choose a different one when you generate the project buildsystem (see [available options](https://cmake.org/cmake/help/v3.23/manual/cmake.1.html)).
> [@alice](#):
>
> How can I know the build tool for these commands on windows?
I assume you are asking how to check which one is used. Perhaps the easiest way to do that is launching `cmake-gui`:
```sh
cd build
cmake ..
cmake-gui .
```
The GUI application shows `Current Generator: `
---
### Author:  [@alice](https://discourse.cmake.org/u/alice)
#### Post date: [February 16, 2022, 11:36am UTC](https://discourse.cmake.org/t/binary-tree/5009/6 "2022-02-16T11:36:33Z")
Q1
```auto
cmake -G "Visual Studio 16 2019"
```
Because I assign the `-G` to “Visual Studio 16 2019”, the build tool will be the “Visual Studio 16 2019” ?
Q2
Which step assigns build tool ( Generate a Project or Build a Project)?
```auto
# the project binary directory
cd build
# Generate a Project Buildsystem
cmake .. -G "Visual Studio 16 2019"
# Build a Project
cmake --build . [-- ]
```
Q3
How to use the parameter `[-- ]`?
[https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#build-a-project](https://cmake.org/cmake/help/v3.23/manual/cmake.1.html#build-a-project)
---
### Author:  [@hex](https://discourse.cmake.org/u/hex)
#### Post date: [February 16, 2022, 12:19pm UTC](https://discourse.cmake.org/t/binary-tree/5009/7 "2022-02-16T12:19:12Z")
Q1: Some generators are for build systems but yes, in a more general way we are generating build tools. I would say that “Visual Studio” is the build tool here. The suffix are version details. Don’t throw stones at me if i’m wrong.
Q2:
> [@hex](#):
>
> You can choose a different one when you generate the project buildsystem
Q3: This is out of scope for CMake. Everything following `--` CMake doesn’t understand, and passes it along to said tool. Any build tool generated by CMake may have options that you want to use.
Here is a real world example for `cmake --build -- `:
```sh
cmake \
-G "Unix Makefiles" \
--build "${BINARY_DIR}" \
-- --no-print-directory
```
`--no-print-directory` is not a CMake option. It is passed on to Make by CMake. You have to consult the documentation of your build tool for available options.
---
### Author:  [@alice](https://discourse.cmake.org/u/alice)
#### Post date: [February 17, 2022, 8:15am UTC](https://discourse.cmake.org/t/binary-tree/5009/9 "2022-02-17T08:15:46Z")
Do you have the sample command for Q3?
---
### Author:  [@hex](https://discourse.cmake.org/u/hex)
#### Post date: [February 17, 2022, 11:02am UTC](https://discourse.cmake.org/t/binary-tree/5009/10 "2022-02-17T11:02:22Z")
yes, i edited my previous post.