title: Print a block of text until the first blank line using awk
body: <p>here is my sample file: </p>
  
  <pre><code>Host dns2
          HostName 172.20.4.80
          User root
          Port 22
  
  Host dns1
          HostName 172.20.4.75
          User root
          Port 22
  
  Host dns3
          HostName 172.20.4.76
          User root
          Port 22
  
  Host dns4
          HostName 172.20.4.77
          User root
          Port 22
  
  Host dns5
          HostName 172.20.4.78
          User root
          Port 22
  
  Host dns6
          HostName 172.20.4.79
          User root
          Port 22
  </code></pre>
  
  <p>i want to print only one block means for example </p>
  
  <pre><code>Host dns1
          HostName 172.20.4.75
          User root
          Port 22
  </code></pre>
  
  <p>output : </p>
  
  <pre><code>Host: dns2  HostName: 172.20.4.80   User: root  Port: 22
  </code></pre>
  
  <p>but in this example all blocks have 4 lines maybe they reach to 5 or more lines later so i want to print from Host to first blank line or remove from Host to first blank line </p>
  
  <p>im really bad at regex and need this to complete my script </p>
  
  <p>thank you</p>