title: sed delete all lines between two lines that contain a string
body: <p>I have a text file with thousand of lines. I want to delete all lines between the line that  starts with XXX and the line that starts with YYY, example</p>
  <pre><code>1
  2
  3
  XXX
  a
  b
  c
  YYY
  x
  z
  y
  </code></pre>
  <p>should be:</p>
  <pre><code>1
  2
  3
  x
  z
  y
  </code></pre>
  <p>Is that possible with sed or similar?</p>