send_string_data

# File lib/net/imap.rb, line 1340
    def send_string_data(str, tag = nil)
      case str
      when ""
        put_string('""')
      when /[\x80-\xff\r\n]/
        # literal
        send_literal(str, tag)
      when /[(){ \x00-\x1f\x7f%*"\\]/
        # quoted string
        send_quoted_string(str)
      else
        put_string(str)
      end
    end