/usr/include/KF5/Syndication/syndication/ is in libkf5syndication-dev 15.12.3-0ubuntu1.
This file is owned by root:root, with mode 0o755.
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/usr/include/KF5/Syndication/syndication/abstractparser.h
/usr/include/KF5/Syndication/syndication/atom/
/usr/include/KF5/Syndication/syndication/atom/atom.h
/usr/include/KF5/Syndication/syndication/atom/category.h
/usr/include/KF5/Syndication/syndication/atom/constants.h
/usr/include/KF5/Syndication/syndication/atom/content.h
/usr/include/KF5/Syndication/syndication/atom/document.h
/usr/include/KF5/Syndication/syndication/atom/entry.h
/usr/include/KF5/Syndication/syndication/atom/generator.h
/usr/include/KF5/Syndication/syndication/atom/link.h
/usr/include/KF5/Syndication/syndication/atom/parser.h
/usr/include/KF5/Syndication/syndication/atom/person.h
/usr/include/KF5/Syndication/syndication/atom/source.h
/usr/include/KF5/Syndication/syndication/category.h
/usr/include/KF5/Syndication/syndication/constants.h
/usr/include/KF5/Syndication/syndication/dataretriever.h
/usr/include/KF5/Syndication/syndication/documentsource.h
/usr/include/KF5/Syndication/syndication/documentvisitor.h
/usr/include/KF5/Syndication/syndication/elementwrapper.h
/usr/include/KF5/Syndication/syndication/enclosure.h
/usr/include/KF5/Syndication/syndication/feed.h
/usr/include/KF5/Syndication/syndication/global.h
/usr/include/KF5/Syndication/syndication/image.h
/usr/include/KF5/Syndication/syndication/item.h
/usr/include/KF5/Syndication/syndication/loader.h
/usr/include/KF5/Syndication/syndication/mapper.h
/usr/include/KF5/Syndication/syndication/parsercollection.h
/usr/include/KF5/Syndication/syndication/person.h
/usr/include/KF5/Syndication/syndication/rdf/
/usr/include/KF5/Syndication/syndication/rdf/contentvocab.h
/usr/include/KF5/Syndication/syndication/rdf/document.h
/usr/include/KF5/Syndication/syndication/rdf/dublincore.h
/usr/include/KF5/Syndication/syndication/rdf/dublincorevocab.h
/usr/include/KF5/Syndication/syndication/rdf/image.h
/usr/include/KF5/Syndication/syndication/rdf/item.h
/usr/include/KF5/Syndication/syndication/rdf/literal.h
/usr/include/KF5/Syndication/syndication/rdf/model.h
/usr/include/KF5/Syndication/syndication/rdf/modelmaker.h
/usr/include/KF5/Syndication/syndication/rdf/node.h
/usr/include/KF5/Syndication/syndication/rdf/nodevisitor.h
/usr/include/KF5/Syndication/syndication/rdf/parser.h
/usr/include/KF5/Syndication/syndication/rdf/property.h
/usr/include/KF5/Syndication/syndication/rdf/rdf.h
/usr/include/KF5/Syndication/syndication/rdf/rdfvocab.h
/usr/include/KF5/Syndication/syndication/rdf/resource.h
/usr/include/KF5/Syndication/syndication/rdf/resourcewrapper.h
/usr/include/KF5/Syndication/syndication/rdf/rssvocab.h
/usr/include/KF5/Syndication/syndication/rdf/sequence.h
/usr/include/KF5/Syndication/syndication/rdf/statement.h
/usr/include/KF5/Syndication/syndication/rdf/syndicationinfo.h
/usr/include/KF5/Syndication/syndication/rdf/syndicationvocab.h
/usr/include/KF5/Syndication/syndication/rdf/textinput.h
/usr/include/KF5/Syndication/syndication/rss2/
/usr/include/KF5/Syndication/syndication/rss2/category.h
/usr/include/KF5/Syndication/syndication/rss2/cloud.h
/usr/include/KF5/Syndication/syndication/rss2/document.h
/usr/include/KF5/Syndication/syndication/rss2/enclosure.h
/usr/include/KF5/Syndication/syndication/rss2/image.h
/usr/include/KF5/Syndication/syndication/rss2/item.h
/usr/include/KF5/Syndication/syndication/rss2/parser.h
/usr/include/KF5/Syndication/syndication/rss2/rss2.h
/usr/include/KF5/Syndication/syndication/rss2/source.h
/usr/include/KF5/Syndication/syndication/rss2/textinput.h
/usr/include/KF5/Syndication/syndication/specificdocument.h
/usr/include/KF5/Syndication/syndication/specificitem.h
/usr/include/KF5/Syndication/syndication/specificitemvisitor.h
/usr/include/KF5/Syndication/syndication/syndication.h
/usr/include/KF5/Syndication/syndication/syndication_export.h
/usr/include/KF5/Syndication/syndication/tools.h