/usr/include/exo-1/exo/ is in libexo-1-dev 0.6.2-4.
This file is owned by root:root, with mode 0o755.
..
/usr/include/exo-1/exo/exo-binding.h
/usr/include/exo-1/exo/exo-cell-renderer-ellipsized-text.h
/usr/include/exo-1/exo/exo-cell-renderer-icon.h
/usr/include/exo-1/exo/exo-config.h
/usr/include/exo-1/exo/exo-enum-types.h
/usr/include/exo-1/exo/exo-execute.h
/usr/include/exo-1/exo/exo-gdk-pixbuf-extensions.h
/usr/include/exo-1/exo/exo-gobject-extensions.h
/usr/include/exo-1/exo/exo-gtk-extensions.h
/usr/include/exo-1/exo/exo-icon-bar.h
/usr/include/exo-1/exo/exo-icon-chooser-dialog.h
/usr/include/exo-1/exo/exo-icon-view.h
/usr/include/exo-1/exo/exo-job.h
/usr/include/exo-1/exo/exo-simple-job.h
/usr/include/exo-1/exo/exo-string.h
/usr/include/exo-1/exo/exo-toolbars-editor-dialog.h
/usr/include/exo-1/exo/exo-toolbars-editor.h
/usr/include/exo-1/exo/exo-toolbars-model.h
/usr/include/exo-1/exo/exo-toolbars-view.h
/usr/include/exo-1/exo/exo-tree-view.h
/usr/include/exo-1/exo/exo-utils.h
/usr/include/exo-1/exo/exo-wrap-table.h
/usr/include/exo-1/exo/exo-xsession-client.h
/usr/include/exo-1/exo/exo.h