# Link between "cmake -B" and CMAKE\_CURRENT\_BINARY\_DIR
**URL:** https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520
**Category:** Code
**Created:** [November 28, 2023, 9:45am UTC](https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520 "2023-11-28T09:45:26Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Oodini](https://discourse.cmake.org/u/Oodini)
#### Post date: [November 28, 2023, 9:45am UTC](https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520/1 "2023-11-28T09:45:26Z")
Hello,
Could you please confirm me that **CMAKE\_CURRENT\_BINARY\_DIR** is set by `cmake -B` ?
If so, it would be good the documentation mentions explicitly this link (documentation of one of them referring the other one).
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### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [November 28, 2023, 1:21pm UTC](https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520/2 "2023-11-28T13:21:28Z")
`CMAKE_CURRENT_BINARY_DIR` changes on each `add_subdirectory` call, so this seems like the wrong link to me. It is, instead, closer to `CMAKE_BINARY_DIR`.
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### Author:  [@Oodini](https://discourse.cmake.org/u/Oodini)
#### Post date: [November 28, 2023, 1:32pm UTC](https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520/3 "2023-11-28T13:32:04Z")
So the **-B** switch would match to the **CMAKE\_CURRENT\_BINARY\_DIR** of the root CMakeLists.txt, and then would be the same as **CMAKE\_BINARY\_DIR**?
EDIT : fixed typo on the switch
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### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [November 29, 2023, 11:49am UTC](https://discourse.cmake.org/t/link-between-cmake-b-and-cmake-current-binary-dir/9520/4 "2023-11-29T11:49:48Z")
> [@Oodini](#):
>
> So the **-D** switch
If you meant `-B`, then this sounds right to me.