title: Awk - Conditionally print an element from a certain row, based on the condition of a different element in a different row
body: <p>Say I have a lot of files with a consistent number of columns and rows, and a sample one looks like this:</p>
  
  <pre><code>1 2 3
  4 5 6
  7 8 9
  </code></pre>
  
  <p>I want to print column 3 of row 2, but only if column 3 of row 3 == 4 (in this case it is 9). I'm using this logic is a means to determine if the file is valid for my use-case, and extract the relevant field if it is.</p>
  
  <p>My attempt, based on other answers to people asking how to isolate certain rows was this: <code>awk 'BEGIN{FNR=3} $3=="4"{FNR=2;print $2}'</code></p>