/usr/include/boost/thread/detail/ is in libboost1.62-dev 1.62.0+dfsg-5.
This file is owned by root:root, with mode 0o755.
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/usr/include/boost/thread/detail/config.hpp
/usr/include/boost/thread/detail/counter.hpp
/usr/include/boost/thread/detail/delete.hpp
/usr/include/boost/thread/detail/force_cast.hpp
/usr/include/boost/thread/detail/function_wrapper.hpp
/usr/include/boost/thread/detail/invoke.hpp
/usr/include/boost/thread/detail/invoker.hpp
/usr/include/boost/thread/detail/is_convertible.hpp
/usr/include/boost/thread/detail/lockable_wrapper.hpp
/usr/include/boost/thread/detail/log.hpp
/usr/include/boost/thread/detail/make_tuple_indices.hpp
/usr/include/boost/thread/detail/memory.hpp
/usr/include/boost/thread/detail/move.hpp
/usr/include/boost/thread/detail/nullary_function.hpp
/usr/include/boost/thread/detail/platform.hpp
/usr/include/boost/thread/detail/singleton.hpp
/usr/include/boost/thread/detail/thread.hpp
/usr/include/boost/thread/detail/thread_group.hpp
/usr/include/boost/thread/detail/thread_heap_alloc.hpp
/usr/include/boost/thread/detail/thread_interruption.hpp
/usr/include/boost/thread/detail/tss_hooks.hpp
/usr/include/boost/thread/detail/variadic_footer.hpp
/usr/include/boost/thread/detail/variadic_header.hpp