# File lib/net/netrc.rb, line 122
    def Netrc.rcname

      # use file indicated by NETRC environment variable if defined
      return ENV['NETRC'] if ENV['NETRC']

      dirs = []
      files = ['.netrc']

      # build candidate list of directories to check
      pw = Etc.getpwuid
      dirs << pw.dir if pw
      dirs << ENV['HOME']
      if IS_WIN32
        dirs << ENV['USERPROFILE']
        dirs << ENV['HOMESHARE']
        dirs << ENV['HOMEDRIVE'] + ENV['HOMEPATH'] || '' if ENV['HOMEDRIVE']
        files << '_netrc'
      end

      # return first found file
      dirs.compact.each do |dir|
        files.each do |file|
          name = File.join(dir, file)
          return name if File.exist?(name)
        end
      end

      # nothing found
      nil
    end