mob/verb/list_directory()
shell("cd > dir.txt")
usr << file2text("dir.txt")
Problem description:
It should in theory just output the current directory of the world, but it does nothing. Not sure if shell() uses the world directory by default though, documentation isn't helpful at all.
Is 'dir.txt' being created at all? If the world is running in trusted mode, you should check in your C:\ directory for it, if it's there you may want to do something like
shell("cd > ./dir.txt")
To see if that helps, I don't work a lot in the Windows command-line these days.