> It’s basically a graph.
do you mean it's a basically a tree? Because if it were just a graph, you could still have edges from the grandparent to the grandchild in addition to the one from the former to the child
do you mean it's a basically a tree? Because if it were just a graph, you could still have edges from the grandparent to the grandchild in addition to the one from the former to the child
It used to be possible ages ago to hard link to directories, which meant that you could have actual cycles and a recursive tree-walking algorithm would never terminated. (As far as I know you can still do this by editing the disk manually, although I think fsck will make a fuss if it detects this.)
You can still, with the right syscalls and drivers, do something like hard links on NTFS (I think they're technically called mount points but it's not the same thing as POSIX ones). I'm not sure if you can still make directory cycles, and you're probably a bad person if you do.
More than DAGs, but instead pretty arbitrary graphs since you can express cycles with hard links.
You can't if you only allow hard links to files.