(PECL sam >= 0.1.0)
SAMConnection::unsubscribe — Cancel a subscription to a specified topic.
$subscriptionId
   [, string $targetTopic
  ] )The "unsubscribe" method is used to delete an existing subscription to a specified topic.
subscriptionIdThe identifier of an existing subscription as returned by a call to the subscribe method.
   This method returns FALSE if an error occurs.
  
Example #1 Delete a subscription
<?php
if (!$conn->unsubscribe($subid)) {
    // The unsubscribe failed!
    echo "Unsubscribe failed ($conn->errno) $conn->error";
}
?>