/usr/ is in libportmidi-dev 1:217-6.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/portmidi.h
/usr/include/porttime.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/libportmidi.a
/usr/lib/x86_64-linux-gnu/libporttime.a
/usr/share/
/usr/share/doc/
/usr/share/doc/libportmidi-dev/
/usr/share/doc/libportmidi-dev/README.txt
/usr/share/doc/libportmidi-dev/README_LINUX.txt
/usr/share/doc/libportmidi-dev/copyright
/usr/share/doc/libportmidi-dev/examples/
/usr/share/doc/libportmidi-dev/examples/Makefile
/usr/share/doc/libportmidi-dev/examples/latency.c
/usr/share/doc/libportmidi-dev/examples/midiclock.c
/usr/share/doc/libportmidi-dev/examples/midithread.c
/usr/share/doc/libportmidi-dev/examples/midithru.c
/usr/share/doc/libportmidi-dev/examples/mm.c
/usr/share/doc/libportmidi-dev/examples/pminternal.h
/usr/share/doc/libportmidi-dev/examples/pmutil.h
/usr/share/doc/libportmidi-dev/examples/qtest.c
/usr/share/doc/libportmidi-dev/examples/simple_test.c
/usr/share/doc/libportmidi-dev/examples/sysex.c
/usr/lib/x86_64-linux-gnu/libportmidi.so
/usr/lib/x86_64-linux-gnu/libporttime.so
/usr/share/doc/libportmidi-dev/changelog.Debian.gz