title: How do I update a datastore variable from inside a bash variable?
body: <p>I have a variable set in a bbclass file like:</p>
  
  <pre><code>#some-class.bbclass
  PROC ??= ""
  </code></pre>
  
  <p>In a recipe inheriting the class, I have a bash function where I modify that variable and immediately read its value. But, the value never gets updated.</p>
  
  <pre><code>#some-bb-file.bb
  inherit some-class.bbclass
  
  some_configure() {
      PROC=$(grep -r "Processor.*${cpu_id}" ... something)
      bbnote "PROC is ${PROC}"
  }
  </code></pre>
  
  <p>I always get "PROC is " in the logs. I have tried printing the output of "(grep -r "Processor.*${cpu_id}" ... something)" and it returns a valid string. Can someone please tell me what I am missing?</p>