/usr/include/goocanvasmm-1.0/goocanvasmm/private/ is in libgoocanvasmm-dev 0.15.4-1.
This file is owned by root:root, with mode 0o755.
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/usr/include/goocanvasmm-1.0/goocanvasmm/private/bounds_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/canvas_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/ellipse_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/ellipsemodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/enums_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/grid_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/gridmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/group_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/groupmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/image_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/imagemodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/item_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/itemmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/itemmodelsimple_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/itemsimple_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/linedash_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/path_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/pathmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/points_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/polyline_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/polylinemodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/rect_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/rectmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/style_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/table_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/tablemodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/text_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/textmodel_p.h
/usr/include/goocanvasmm-1.0/goocanvasmm/private/widget_p.h