title: how to Find a substring in a bash shell script variable
body: <p>I have a variable like below.</p>
  
  <pre><code>variable = This script is not found
  
  if [[ "$variable" = ~ "not found" ]];
  then
  echo "Not Found"
  else
  echo "Its there"
  if
  </code></pre>
  
  <p>while executing im getting below err,</p>
  
  <pre><code>line 4: syntax error in conditional expression
  ./test.sh: line 4: syntax error near `found"'
  ./test.sh: line 4: `if [[ "$variable" = ~ "not found" ]]; '
  </code></pre>
  
  <p>could anyone point me, What im missing here?</p>