I don't have the reputation to comment, so I'll put this here.
It almost looks like the tree
command is aliased to sed
on your machine. When I run tree -C
on my machine, I get the expected behavior. When I run sed -C
on my computer, I get the exact same output that you get when you run tree -C
.
Is there any entry in your ~/.bashrc
file that defines an alias like that?