title: How can I modify the application file of an application that is currently running (on Linux)?
body: <p>I have an application running called AppFS.  This application has an ext2 filesystem just attached to the end of the file (it's positioned so that the application binary exists in a 1MB spacing area, followed by the ext2 data).</p>
  
  <p>Now I've got FUSE embedded in the program and I've managed to extract the filesystem out of the application data into a temporary file so that FUSE can mount / use it.</p>
  
  <p>The problem I have now is writing the temporary file back <em>into</em> the application file.  I get "Text file busy" presumably because the application has locked itself and won't let writes occur.</p>
  
  <p>Is there a way I can force the file to become unlocked so I can write data to it?  (It's important to note that I'm not changing the application binary area - just rewriting the ext2 component.)  It needs to be unlocked without requiring root permissions (unlocked by the same user who started the application).</p>