* Returns: on failure - reason = NULL
* on success - reason - pointer to reason
*/
-void check_if_volume_valid_or_recyclable(JCR *jcr, MEDIA_DBR *mr, char **reason)
+void check_if_volume_valid_or_recyclable(JCR *jcr, MEDIA_DBR *mr, const char **reason)
{
int ok;