$ABORT_TRANSW, or Abort Transaction and Wait, is a system service that ends a transaction by aborting it. $ABORT_TRANSW always waits for the request to complete before returning to the caller. Other than this, it is identical to $ABORT_TRANS. Do not call $ABORT_TRANSW from AST level, or from an access mode that is more privileged than the DECdtm calls made by any resource manager participant in the transaction. If you do, the $ABORT_TRANSW service will wait indefinitely.
SYS$ABORT_TRANSW [efn] ,[flags] ,iosb [,[astadr] ,[astprm] ,[tid] ,[reason] ,[bid]]
int sys$abort_transw (unsigned int efn, unsigned int flags, struct _iosb *iosb,...);