There are three remaining CxObjects: signalCxObj = CxObj *CxSignal(struct Task *,LONG signal); debugCxObj = CxObj *CxDebug(LONG ID); customCxObj = CxObj *CxCustom(LONG *customfunction(), LONG cxmID); When a signal CxObject receives a CxMessage, it signals a task. When a debug CxObject receives a CxMessage, it sends debugging information to the serial port using kprintf(). Note that the debug CxObj did not work before V37. A custom CxObject is the only means by which a commodity can directly modify input events as they pass through the Commodities network as CxMessages. The custom CxObject is probably the most dangerous of the CxObjects to use. Unlike the rest of the code a commodities programmer writes, the code passed to a custom CxObject runs as part of the input.device task, putting severe restrictions on the function. No DOS or Intuition functions can be called. No assumptions can be made about the values of regist ers upon entry. Any function passed to CxCustom() should be very quick and very simple, with a minimum of stack usage. Commodities Exchange calls a custom CxObject's function as follows: void customfunction(CxMsg *cxm, CxObj *customcxobj); where cxm is a pointer to a CxMessage corresponding to a real input event, and customcxobj is a pointer to the custom CxObject. The custom function can extract the pointer to the input event by calling CxMsgData(). Before passing the CxMessage to the cu stom function, Commodities Exchange sets the CxMessage's ID to the ID passed to CxCustom().
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