it's already implemented in hfs
switch to expert mode
open 'menu' > 'virtual file system'
and check 'List protected items only for users'
by using this option, only items that do not contain a lock will be visible to the user,
for a connected user, those that are not authorized are masked
switch to expert mode
open 'menu' > 'virtual file system'
and check 'List protected items only for users'
by using this option, only items that do not contain a lock will be visible to the user,
for a connected user, those that are not authorized are masked