title: GNUMAKE: find if a string is present in a file before updating it
body: <p>I am trying to add "description" to $(@)/etc/release file only if its not there already</p>
  
  <pre><code>$(PROJECTDIR)/projectroot:
  if [ grep -q "description" "$(@)/etc/release" ]; then \
    echo "description :" $(PLATFORM) &gt;&gt; $(@)/etc/release; \
  fi
  </code></pre>
  
  <p>but it throws error "/bin/sh: line 0: [: too many arguments" and not doing anything with release file. can you please help. Thanks a lot.</p>