# CMAKE_CURRENT_BINARY_DIR

The path to the binary directory currently being processed.

This is the full path to the build directory that is currently being processed by cmake. Each directory added by `add_subdirectory()` will create a binary directory in the build tree, and as it is being processed this variable will be set. For in-source builds this is the current source directory being processed.

When run in `cmake -P` script mode, CMake sets the variables `CMAKE_BINARY_DIR`, `CMAKE_SOURCE_DIR`, `CMAKE_CURRENT_BINARY_DIR` and `CMAKE_CURRENT_SOURCE_DIR` to the current working directory.

Modifying `CMAKE_CURRENT_BINARY_DIR` has undefined behavior.