/usr/ is in ruby-rd 0.6.38-2.
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..
/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/rd/
/usr/lib/ruby/vendor_ruby/rd/complex-list-item.rb
/usr/lib/ruby/vendor_ruby/rd/rbl-suite.rb
/usr/lib/ruby/vendor_ruby/rd/labeled-element.rb
/usr/lib/ruby/vendor_ruby/rd/inline-element.rb
/usr/lib/ruby/vendor_ruby/rd/rdblockparser.tab.rb
/usr/lib/ruby/vendor_ruby/rd/package.rb
/usr/lib/ruby/vendor_ruby/rd/rd2rmi-lib.rb
/usr/lib/ruby/vendor_ruby/rd/rd2rdo-lib.rb
/usr/lib/ruby/vendor_ruby/rd/head-filter.rb
/usr/lib/ruby/vendor_ruby/rd/tree.rb
/usr/lib/ruby/vendor_ruby/rd/rdinlineparser.tab.rb
/usr/lib/ruby/vendor_ruby/rd/rdfmt.rb
/usr/lib/ruby/vendor_ruby/rd/filter.rb
/usr/lib/ruby/vendor_ruby/rd/list.rb
/usr/lib/ruby/vendor_ruby/rd/rd2html-lib.rb
/usr/lib/ruby/vendor_ruby/rd/output-format-visitor.rb
/usr/lib/ruby/vendor_ruby/rd/rd2html-ext-opt.rb
/usr/lib/ruby/vendor_ruby/rd/block-element.rb
/usr/lib/ruby/vendor_ruby/rd/rdvisitor.rb
/usr/lib/ruby/vendor_ruby/rd/document-struct.rb
/usr/lib/ruby/vendor_ruby/rd/element.rb
/usr/lib/ruby/vendor_ruby/rd/rbl-file.rb
/usr/lib/ruby/vendor_ruby/rd/loose-struct.rb
/usr/lib/ruby/vendor_ruby/rd/rdblockparser.ry
/usr/lib/ruby/vendor_ruby/rd/parser-util.rb
/usr/lib/ruby/vendor_ruby/rd/methodlist.rb
/usr/lib/ruby/vendor_ruby/rd/reference-resolver.rb
/usr/lib/ruby/vendor_ruby/rd/rd-struct.rb
/usr/lib/ruby/vendor_ruby/rd/version.rb
/usr/lib/ruby/vendor_ruby/rd/rdinlineparser.ry
/usr/lib/ruby/vendor_ruby/rd/visitor.rb
/usr/lib/ruby/vendor_ruby/rd/rd2html-opt.rb
/usr/lib/ruby/vendor_ruby/rd/search-file.rb
/usr/lib/ruby/vendor_ruby/rd/rd2man-lib.rb
/usr/lib/ruby/vendor_ruby/rd/rd2html-ext-lib.rb
/usr/lib/ruby/vendor_ruby/rd/desclist.rb
/usr/share/
/usr/share/doc/
/usr/share/doc/ruby-rd/
/usr/share/doc/ruby-rd/rd-draft.html
/usr/share/doc/ruby-rd/README.rd
/usr/share/doc/ruby-rd/README.rd.ja
/usr/share/doc/ruby-rd/changelog.Debian.gz
/usr/share/doc/ruby-rd/rd-draft.ja.html
/usr/share/doc/ruby-rd/copyright
/usr/share/doc/ruby-rd/README.ja.html
/usr/share/doc/ruby-rd/rd-draft.rd.gz
/usr/share/doc/ruby-rd/README.html
/usr/share/doc/ruby-rd/rd-draft.rd.ja.gz
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/1.9.1/
/usr/share/rubygems-integration/1.9.1/specifications/
/usr/share/rubygems-integration/1.9.1/specifications/rdtool-0.6.38.gemspec
/usr/share/rubygems-integration/2.0/
/usr/share/rubygems-integration/2.0/specifications/
/usr/share/rubygems-integration/2.0/specifications/rdtool-0.6.38.gemspec