/usr/lib/ is in ruby-ffi-yajl 2.3.1-1build1.
This file is owned by root:root, with mode 0o755.
..
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/ffi_yajl/
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/MIT-LICENSE
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/encode.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/encode_json_and_marshal.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/encode_json_and_yaml.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/encode_profile.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/http.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse_json_and_marshal.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse_json_and_yaml.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse_profile.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse_profile_ruby_prof.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/parse_stream.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark/subjects/
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/usr/lib/ruby/vendor_ruby/ffi_yajl/benchmark.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/encoder.rb
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/usr/lib/ruby/vendor_ruby/ffi_yajl/map_library_name.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/parser.rb
/usr/lib/ruby/vendor_ruby/ffi_yajl/platform.rb
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/usr/lib/ruby/vendor_ruby/libyajl2.rb
/usr/lib/x86_64-linux-gnu/
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