+B<mount.captive>(8) defaults to filesystem files B<644> - read-write for system
+root (or the regular user owner) and read-only for others. You can force the
+mode B<600> by this option (read-write for the owner, inaccessible for others).
+Mode B<755> or <700> applies to directories. Options B<fmask>/B<dmask> will
+be OR-ed to the private/public permissions set by this option.