/usr/ is in libbson-dev 1.9.2-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/doc/libbson-dev/README
/usr/include/
/usr/include/libbson-1.0/
/usr/include/libbson-1.0/bcon.h
/usr/include/libbson-1.0/bson-atomic.h
/usr/include/libbson-1.0/bson-clock.h
/usr/include/libbson-1.0/bson-compat.h
/usr/include/libbson-1.0/bson-config.h
/usr/include/libbson-1.0/bson-context.h
/usr/include/libbson-1.0/bson-decimal128.h
/usr/include/libbson-1.0/bson-endian.h
/usr/include/libbson-1.0/bson-error.h
/usr/include/libbson-1.0/bson-iter.h
/usr/include/libbson-1.0/bson-json.h
/usr/include/libbson-1.0/bson-keys.h
/usr/include/libbson-1.0/bson-macros.h
/usr/include/libbson-1.0/bson-md5.h
/usr/include/libbson-1.0/bson-memory.h
/usr/include/libbson-1.0/bson-oid.h
/usr/include/libbson-1.0/bson-reader.h
/usr/include/libbson-1.0/bson-stdint.h
/usr/include/libbson-1.0/bson-string.h
/usr/include/libbson-1.0/bson-types.h
/usr/include/libbson-1.0/bson-utf8.h
/usr/include/libbson-1.0/bson-value.h
/usr/include/libbson-1.0/bson-version-functions.h
/usr/include/libbson-1.0/bson-version.h
/usr/include/libbson-1.0/bson-writer.h
/usr/include/libbson-1.0/bson.h
/usr/lib/
/usr/lib/x86_64-linux-gnu/
/usr/lib/x86_64-linux-gnu/cmake/
/usr/lib/x86_64-linux-gnu/cmake/libbson-1.0/
/usr/lib/x86_64-linux-gnu/cmake/libbson-1.0/libbson-1.0-config-version.cmake
/usr/lib/x86_64-linux-gnu/cmake/libbson-1.0/libbson-1.0-config.cmake
/usr/lib/x86_64-linux-gnu/pkgconfig/
/usr/lib/x86_64-linux-gnu/pkgconfig/libbson-1.0.pc
/usr/share/
/usr/share/doc/
/usr/share/doc/libbson-dev/
/usr/share/doc/libbson-dev/copyright
/usr/lib/x86_64-linux-gnu/libbson-1.0.so
/usr/share/doc/libbson-dev/changelog.Debian.gz