title: Linux: Block until a string is matched in a file ("tail + grep with blocking")
body: <p>Is there some one-line way in bash/GNU tools to block until there's a string matched in a file? Ideally, with timeout. I want to avoid multi-line loop.</p>
  
  <p><strong>Update:</strong> Seems like I should have emphasize that I want the process to end when the string is matched.</p>