title: How do you generate Boundary In PHP?
body: <p>I'm using Curl library to simulate "multipart-form-data" submission, then I noticed that I need to generate a unique string, but I have no idea how to do that. </p>
  
  <p>For example:</p>
  
  <pre><code>Content-Type: multipart/form-data;  
  boundary=---------------------------491299511942
  Content-Length: 95418
  -----------------------------491299511942
  Content-Disposition: form-data; name="a"
  -----------------------------491299511942
  Content-Disposition: form-data; name="b"
  /page.asp
  -----------------------------491299511942
  Content-Disposition: form-data; name="c"
  -----------------------------491299511942
  Content-Disposition: form-data; name="d"
  true
  -----------------------------491299511942
  Content-Disposition: form-data; name="e"
  1
  -----------------------------491299511942
  Content-Disposition: form-data; name="f"
  </code></pre>
  
  <p>How to generate that boundary? From library or just some hack?</p>
  
  <p><strong>EDIT</strong>: in this example Boundary=491299511942</p>