Ends a transaction by attempting to commit it, and returns the
    outcome of the transaction.

    $END_TRANSW always waits for the request to complete before
    returning to the caller. Other than this, it is identical to
    $END_TRANS.

    Format

      SYS$END_TRANSW  [efn] ,[flags] ,iosb [,[astadr] ,[astprm]

                      ,[tid]]

    C Prototype

      int sys$end_transw  (unsigned int efn, unsigned int flags,

                          struct _iosb *iosb,...);