Ruby realpath returns the unc path if available for mapped drive

unc_path.rb

# * *author*      : jtzero
# * *version*     : 1.2.3
# * *description* : returns the unc path of a file when using realdir
#
require 'win32api'
class IO
  WNetGetConnection = begin 
                        Win32API.new("mpr.dll", "WNetGetConnection", ['P','P','P'], 'L')
                      rescue #if not windows just return 0
                        lambda {|locate, remote, size| remote = local; next 0 }
                      end
  # wrapper for WNetGetConnection
  # * *args*                       :
  #   - +local_name+              -> the name on this computer
  #   - +str_size=1024+           -> the size of the empty string to be passed to WNetGetConnection
  #   - +fail_on_not_found=false+ -> fail if there is no network connection for that local_name
  def self.wnet_get_connection(local_name, str_size=1024, fail_on_not_found=false)
    remote_name = "\0" * str_size
    error_code = WNetGetConnection.call(local_name, remote_name, [str_size].pack('L'))

    raise("Windows error #{error_code} consult http://msdn.microsoft.com 'System Error Codes'") unless error_code == 0 or !(fail_on_not_found and error_code == 2250)
    return remote_name.rstrip.gsub('\\', '/') unless remote_name.rstrip.empty? # I got nothin, return nil
  end
end

class File
  class << self
    # windows-only
    # * *args*     :
    #   - +drive+ -> the drive to check, if nothing is given it will get it 
    def on_network_drive?(drive=get_drive_name(Dir.orig_pwd))
      wnet_get_connection(drive)
    end
    
    # windows-only
    # * *args*    :
    #   - +path+ ->
    def get_unc_path(path)
      unc_path = on_network_drive?(get_drive_name(path))
      unc_path + path.split(/(:)/, 2).last if unc_path
    end
    
    #
    #
    # modded for windows unc_path
    alias_method :orig_realpath, :realpath
    def realpath(path, dir_string=nil)
      get_unc_path(path) || orig_realpath(path, dir_string)
    end
   private
    # windows-only will return whole path otherwise
    # * *args*    :
    #   - path   -> the path that the derive will be extracted from
    # * *returns* : String, the drive or the whole path
    def get_drive_name(path)
      path.split(/(:)/, 2)[0..1].join
    end
  end
end

#puts File.realpath Dir.pwd