/usr/include/libcmis-c-0.5/libcmis-c/ is in libcmis-dev 0.5.1+git20160603-3+b1.
This file is owned by root:root, with mode 0o755.
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/usr/include/libcmis-c-0.5/libcmis-c/allowable-actions.h
/usr/include/libcmis-c-0.5/libcmis-c/document.h
/usr/include/libcmis-c-0.5/libcmis-c/error.h
/usr/include/libcmis-c-0.5/libcmis-c/folder.h
/usr/include/libcmis-c-0.5/libcmis-c/libcmis-c.h
/usr/include/libcmis-c-0.5/libcmis-c/oauth2-data.h
/usr/include/libcmis-c-0.5/libcmis-c/object-type.h
/usr/include/libcmis-c-0.5/libcmis-c/object.h
/usr/include/libcmis-c-0.5/libcmis-c/property-type.h
/usr/include/libcmis-c-0.5/libcmis-c/property.h
/usr/include/libcmis-c-0.5/libcmis-c/rendition.h
/usr/include/libcmis-c-0.5/libcmis-c/repository.h
/usr/include/libcmis-c-0.5/libcmis-c/session-factory.h
/usr/include/libcmis-c-0.5/libcmis-c/session.h
/usr/include/libcmis-c-0.5/libcmis-c/types.h
/usr/include/libcmis-c-0.5/libcmis-c/vectors.h