title: Format output of xentop
body: <p>The command <code>xentop -bi1</code> outputs the following:</p>
  
  <pre><code>NAME  STATE   CPU(sec) CPU(%)     MEM(k) MEM(%)  MAXMEM(k) MAXMEM(%) VCPUS NETS NETTX(k) NETRX(k) VBDS   VBD_OO   VBD_RD   VBD_WR  VBD_RSECT  VBD_WSECT SSID
    Domain-0 -----r      37719    0.0    2096776    6.4   no limit       n/a     1    0        0        0    0        0        0        0          0          0    0
    testvm01 --b---         69    0.0     131072    0.4     131072       0.4     1    1     2388     1670    2        0     3358    15802     154314     273808    0
  xenwin2008 --b---       8208    0.0    1052628    3.2    1052672       3.2     1    2     1361        0    2        0        0        0          0          0    0
  </code></pre>
  
  <p>I want to output only the cpu usage of testvm01</p>
  
  <p>So, i use grep: <code>xentop -bi1 | grep testvm01</code></p>
  
  <pre><code>testvm01 --b---         69    0.0     131072    0.4     131072       0.4     1    1     2389     1672    2        0     3358    15826     154314     274080    0
  </code></pre>
  
  <p>How to get only the value "0.0"?</p>