instance method File::Stat#world_writable?
world_writable? -> Fixnum | nil-
If stat is writable by others, returns an integer representing the file permission bits of stat. Returns nil otherwise. The meaning of the bits is platform dependent; on Unix systems, see stat(2).
m = File.stat("/tmp").world_writable? # => 511 sprintf("%o", m) # => "777"
class File::Stat
