/usr/ is in libpsocksxx-dev 1.1.0-1.2.
This file is owned by root:root, with mode 0o755.
..
/usr/share/
/usr/share/doc/
/usr/share/doc/libpsocksxx-dev/
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/share/doc/libpsocksxx-dev/README.md
/usr/share/doc/libpsocksxx-dev/copyright
/usr/include/
/usr/include/psocksxx/
/usr/include/psocksxx/lsockaddr.h
/usr/include/psocksxx/osockstream.h
/usr/include/psocksxx/sockexception.h
/usr/include/psocksxx/iosockstream.h
/usr/include/psocksxx/nsockstream.h
/usr/include/psocksxx/socktimeoutexception.h
/usr/include/psocksxx/lsockstream.h
/usr/include/psocksxx/sockstreambuf.h
/usr/include/psocksxx/nsockaddr.h
/usr/include/psocksxx/udpnsockstream.h
/usr/include/psocksxx/isockstream.h
/usr/include/psocksxx/iosocks.h
/usr/include/psocksxx/sockaddr.h
/usr/include/psocksxx/tcpnsockstream.h
/usr/share/doc/libpsocksxx-dev/changelog.Debian.gz
/usr/lib/x86_64-linux-gnu/libpsocksxx.so