/usr/ is in ruby-ffi-rzmq-core 1.0.4-3.
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/usr/lib/
/usr/lib/ruby/
/usr/lib/ruby/vendor_ruby/
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/structures.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/constants.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/libzmq4.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/libzmq.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/utilities.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/libc.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core/version.rb
/usr/lib/ruby/vendor_ruby/ffi-rzmq-core.rb
/usr/share/
/usr/share/rubygems-integration/
/usr/share/rubygems-integration/all/
/usr/share/rubygems-integration/all/specifications/
/usr/share/rubygems-integration/all/specifications/ffi-rzmq-core-1.0.4.gemspec
/usr/share/doc/
/usr/share/doc/ruby-ffi-rzmq-core/
/usr/share/doc/ruby-ffi-rzmq-core/copyright
/usr/share/doc/ruby-ffi-rzmq-core/changelog.Debian.gz