Authorizes a new branch to be added to a transaction.
    Format
      SYS$ADD_BRANCH  [efn] ,[flags] ,iosb ,[astadr] ,[astprm] ,tid
                      ,tm_name ,bid
    C Prototype
      int sys$add_branch  (unsigned int efn, unsigned int
                          flags, struct _iosb *iosb, void
                          (*astadr)(__unknown_params), int astprm,
                          unsigned int tid [4], void *tmname,
                          unsigned int bid [4]);
Additional Information:
explode
extract