(PHP 4 <= 4.1.0, PECL dbplus >= 0.9)
dbplus_getlock — Get a write lock on a tuple
$relation
   , string $tuple
   )
   Requests a write lock on the specified tuple. 
  
   Returns zero on success or a non-zero error code, especially 
   DBPLUS_ERR_WLOCKED on failure.
  
This function is EXPERIMENTAL. The behaviour of this function, its name, and surrounding documentation may change without notice in a future release of PHP. This function should be used at your own risk.