/usr/share/man/man3/wsyncdown.3ncurses.gz is in ncurses-doc 6.0+20160213-1ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/man/man3/window.3ncurses.gz
/usr/share/man/man3/window.3ncurses.gz