/usr/share/man/man3/ is in libxcursor-dev 1:1.1.15-1.
This file is owned by root:root, with mode 0o755.
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/usr/share/man/man3/Xcursor.3.gz
/usr/share/man/man3/XcursorCursorsCreate.3.gz
/usr/share/man/man3/XcursorCursorsDestroy.3.gz
/usr/share/man/man3/XcursorFilenameLoad.3.gz
/usr/share/man/man3/XcursorFilenameLoadAllImages.3.gz
/usr/share/man/man3/XcursorFilenameLoadCursor.3.gz
/usr/share/man/man3/XcursorFilenameLoadImage.3.gz
/usr/share/man/man3/XcursorFilenameLoadImages.3.gz
/usr/share/man/man3/XcursorFilenameSave.3.gz
/usr/share/man/man3/XcursorFilenameSaveImages.3.gz
/usr/share/man/man3/XcursorGetDefaultSize.3.gz
/usr/share/man/man3/XcursorGetTheme.3.gz
/usr/share/man/man3/XcursorImageCreate.3.gz
/usr/share/man/man3/XcursorImageDestroy.3.gz
/usr/share/man/man3/XcursorImagesCreate.3.gz
/usr/share/man/man3/XcursorImagesDestroy.3.gz
/usr/share/man/man3/XcursorLibraryLoadCursor.3.gz
/usr/share/man/man3/XcursorLibraryLoadCursors.3.gz
/usr/share/man/man3/XcursorLibraryLoadImage.3.gz
/usr/share/man/man3/XcursorLibraryLoadImages.3.gz
/usr/share/man/man3/XcursorSetDefaultSize.3.gz
/usr/share/man/man3/XcursorSetTheme.3.gz
/usr/share/man/man3/XcursorShapeLoadCursor.3.gz
/usr/share/man/man3/XcursorShapeLoadCursors.3.gz
/usr/share/man/man3/XcursorShapeLoadImage.3.gz
/usr/share/man/man3/XcursorShapeLoadImages.3.gz
/usr/share/man/man3/XcursorSupportsARGB.3.gz
/usr/share/man/man3/XcursorXcFileLoad.3.gz
/usr/share/man/man3/XcursorXcFileLoadAllImages.3.gz
/usr/share/man/man3/XcursorXcFileLoadImage.3.gz
/usr/share/man/man3/XcursorXcFileLoadImages.3.gz
/usr/share/man/man3/XcursorXcFileSave.3.gz