This example creates a new target pointing to the site http://www.foo.com/help/, with instructions to walk across foreign links, delete a local page if it is detected that it has been removed from the remote, retrieve images, walk on entire site using HTTP GET method. The content will be stored in /DAV/sites/www_foo_com collection in the local WebDAV repository.

create procedure
  DB.DBA.my_hook (
    in host varchar, in collection varchar, out url varchar, in my_data any
  )
{
  declare next_url varchar;
  whenever not found goto done;

  -- we trying to extract the oldest entry
  declare cr cursor for select VQ_URL from WS.WS.VFS_QUEUE
      where VQ_HOST = host and VQ_ROOT = collection and VQ_STAT = 'waiting'
      order by VQ_HOST, VQ_ROOT, VQ_TS for update;

  open cr;
  while (1)
  {
    fetch cr into next_url;
    if (get_keyword (host, my_data, null) is not null) -- process if host not in black-list
    {
      update WS.WS.VFS_QUEUE set VQ_STAT = 'pending'
          where VQ_HOST = host and VQ_ROOT = collection and VQ_URL = next_url;
      url := next_url;
      close cr;
      return 1;
    }
    else -- otherwise continue finding
        update WS.WS.VFS_QUEUE set VQ_STAT = 'retrieved'
          where VQ_HOST = host and VQ_ROOT = collection and VQ_URL = next_url;
    }
done:
  -- if we arrive at the bottom of the queue return false to stop processing
  close cr;
  return 0;
}
;