flags = File::FNM_PATHNAME | File::FNM_DOTMATCH
File.fnmatch("lib/*.rb", "lib/a.rb", flags) # => true
File.fnmatch("lib/*.rb", "lib/a/b.rb", flags) # => false
File.fnmatch("lib/**/*.rb", "lib/a.rb", flags) # => true
File.fnmatch("lib/**/*.rb", "lib/a/b.rb", flags) # => true