title: How to write a Python console program can output like the top command in Linux?
body: <p>The output of top command in Linux like bellow:</p>
  
  <blockquote>
    <p>Tasks: 158 total,   1 running, 157 sleeping,   0 stopped,   0 zombie
    Cpu(s):  6.3%us,  3.2%sy,  0.0%ni, 89.9%id,  0.2%wa,  0.0%hi,  0.2%si,
    0.0%st Mem:   8264212k total,  2637492k used,  5626720k free,   299884k buffers Swap:  4192924k total,        0k used,  4192924k free,
    2010332k cached</p>
    
    <p>PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND<br>
    7178 mysql     15   0 52876  31m 4680 S 21.3  0.4 308:12.04 mysqld<br>
    2262 www       16   0 28092  11m 4764 S  4.0  0.1   2:02.31 php-cgi<br>
    2110 www       16   0 27956  11m 4888 S  3.7  0.1   2:04.51 php-cgi<br>
    2005 www       16   0 28680  12m 4872 S  3.0  0.2   2:04.10 php-cgi<br>
    1955 www       16   0 28476  12m 5220 S  2.7  0.1   2:06.51 php-cgi<br>
    2030 www       16   0 28260  11m 4872 S  2.0  0.1   2:05.27 php-cgi<br>
    7044 www       15   0 24348  19m  932 S  0.7  0.2   1:58.38 nginx     </p>
  </blockquote>
  
  <p>Only part of the content changes constantly.</p>
  
  <p>I can only output a single line keeps changing constantly without newline:</p>
  
  <pre><code>import  sys
  import  time
  
  if __name__ == '__main__':
      i = 0
      while True:
          sys.stdout.write('i = %d.\r' % i)
          sys.stdout.flush()
          time.sleep(1)
          i += 1
  </code></pre>
  
  <p>I want to know how to output multiline like the top command(keeps changing constantly without newline).</p>
  
  <p>Sorry, My English is poor. Hope that makes sense.</p>
  
  <p>Thanks,
  Qi</p>