title: Replace 2nd line in flat file
body: <p>I am new bee for shell script. Please redirect me to correct post if this question is redundant.</p>
  
  <p>I have file.txt which has text like below and want to change the 2nd row in file<br></p>
  
  <pre><code>Property1=0
  Property2=0 50 14 1/1 * ? *
  Property3=0
  </code></pre>
  
  <p>I want to replace 2nd line to change 50 14 to current time,  file will look like<br></p>
  
  <pre><code>Property1=0
  Property2=0 58 15 1/1 * ? *
  Property3=0
  </code></pre>
  
  <p>and next time it will look like <br></p>
  
  <pre><code>Property1=0
  Property2=0 03 16 1/1 * ? *
  Property3=0
  </code></pre>
  
  <p>Please help me how to change 2nd line.</p>