/usr/include/ is in libclaw-net-dev 1.7.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/claw/
/usr/include/claw/socket_traits_win32.hpp
/usr/include/claw/basic_socket.hpp
/usr/include/claw/socket_traits_unix.hpp
/usr/include/claw/socket_traits.hpp
/usr/include/claw/socket_server.hpp
/usr/include/claw/impl/
/usr/include/claw/impl/basic_socketbuf.tpp
/usr/include/claw/impl/socket_server.tpp
/usr/include/claw/impl/isocket_stream.tpp
/usr/include/claw/impl/osocket_stream.tpp
/usr/include/claw/impl/socket_stream.tpp
/usr/include/claw/isocket_stream.hpp
/usr/include/claw/socket_stream.hpp
/usr/include/claw/osocket_stream.hpp
/usr/include/claw/basic_socketbuf.hpp