title: grep -Ff producing invalid output
body: <p>I'm using</p>
  
  <p>code -</p>
  
  <pre><code> grep -Ff list.txt C:/data/*.txt &gt; found.txt
  </code></pre>
  
  <p>but it keeps outputting invalid responses, lines don't contain the emails i input..</p>
  
  <p>list.txt contains -</p>
  
  <pre><code>email@email.com
  customer@email.com
  imadmin@gmail.com
  newcustomer@email.com
  helloworld@yes.com
  </code></pre>
  
  <p>and so on.. email to match on each line,</p>
  
  <p>search files contain -</p>
  
  <pre><code>user1:phonenumber1:email@email.com:last-active:recent
  user2:phonennumber2:customer@email.com:last-active:inactive
  user3:phonenumber3:blablarandom@bla.com:last-active:never
  </code></pre>
  
  <p>then another may contain -</p>
  
  <pre><code>blublublu         email@email.com         phonenumber         subscribed
  nanananana        customer@email.com      phonenumber         unsubscribed
  useruser          noemailinput@noemail.com       phonenumber      pending
  </code></pre>
  
  <p>so what I'm trying to do is present grep with a list of emails/list of strings " list.txt " and to then search the directory provided for matches of each string and output the entire line that contains each match.</p>
  
  <p>example of output in this case would be -</p>
  
  <pre><code>user1:phonenumber1:email@email.com:last-active:recent
  user2:phonennumber2:customer@email.com:last-active:inactive
  blublublu         email@email.com         phonenumber         subscribed
  nanananana        customer@email.com      phonenumber         unsubscribed
  </code></pre>
  
  <p>yet it wouldn't output the other two lines -</p>
  
  <pre><code> user3:phonenumber3:blablarandom@bla.com:last-active:never
   useruser          noemailinput@noemail.com       phonenumber      pending
  </code></pre>
  
  <p>because no string is within that line.</p>