/usr/ is in libsylph-dev 1.1.0-13.
This file is owned by root:root, with mode 0o755.
..
/usr/include/
/usr/include/sylph/
/usr/include/sylph/prefs_common.h
/usr/include/sylph/compose.h
/usr/include/sylph/xml.h
/usr/include/sylph/imap.h
/usr/include/sylph/sylmain.h
/usr/include/sylph/folder.h
/usr/include/sylph/procmime.h
/usr/include/sylph/filter.h
/usr/include/sylph/defs.h
/usr/include/sylph/uuencode.h
/usr/include/sylph/nntp.h
/usr/include/sylph/pop.h
/usr/include/sylph/prefs_account.h
/usr/include/sylph/md5.h
/usr/include/sylph/recv.h
/usr/include/sylph/md5_hmac.h
/usr/include/sylph/unmime.h
/usr/include/sylph/customheader.h
/usr/include/sylph/displayheader.h
/usr/include/sylph/utils.h
/usr/include/sylph/news.h
/usr/include/sylph/procheader.h
/usr/include/sylph/session.h
/usr/include/sylph/procmsg.h
/usr/include/sylph/socket.h
/usr/include/sylph/mh.h
/usr/include/sylph/enums.h
/usr/include/sylph/base64.h
/usr/include/sylph/stringtable.h
/usr/include/sylph/prefs.h
/usr/include/sylph/ssl.h
/usr/include/sylph/account.h
/usr/include/sylph/html.h
/usr/include/sylph/virtual.h
/usr/include/sylph/quoted-printable.h
/usr/include/sylph/codeconv.h
/usr/include/sylph/mbox.h
/usr/include/sylph/smtp.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/libsylph.a
/usr/share/
/usr/share/doc/
/usr/share/doc/libsylph-dev/
/usr/share/doc/libsylph-dev/examples/
/usr/share/doc/libsylph-dev/examples/libsylph-listsummary.c
/usr/share/doc/libsylph-dev/examples/libsylph-send.c
/usr/share/doc/libsylph-dev/examples/README
/usr/share/doc/libsylph-dev/examples/libsylph-pop.c
/usr/share/doc/libsylph-dev/examples/libsylph-createmailbox.c
/usr/share/doc/libsylph-dev/examples/libsylph-listfolder.c
/usr/share/doc/libsylph-dev/examples/README.ja
/usr/share/doc/libsylph-dev/examples/libsylph-compose.c
/usr/share/doc/libsylph-dev/examples/libsylph-template.c
/usr/share/doc/libsylph-dev/examples/libsylph-listprefs.c
/usr/share/doc/libsylph-dev/copyright
/usr/lib/x86_64-linux-gnu/libsylph.so
/usr/share/doc/libsylph-dev/NEWS.gz
/usr/share/doc/libsylph-dev/README.gz
/usr/share/doc/libsylph-dev/README.ja.gz
/usr/share/doc/libsylph-dev/TODO
/usr/share/doc/libsylph-dev/changelog.Debian.gz