DIRECTORYDriverTypes USING [DeviceType],NSAddress USING [HostNumber, NetworkNumber],BufferDefs USING [Buffer];SpecialCommunication: DEFINITIONS =BEGIN OPEN NSAddress;RoutersFunction: TYPE = {vanillaRouting, interNetworkRouting};PhysicalMedium: TYPE = DriverTypes.DeviceType;SetRouterFunction: PROCEDURE [newFunction: RoutersFunction, numberINRBuffers: CARDINAL _ 20]RETURNS [oldFunction: RoutersFunction];GetRouterFunction: PROCEDURE RETURNS [RoutersFunction];SetNetworkID: PROCEDURE [physicalOrder: CARDINAL, medium: PhysicalMedium, newNetID: NetworkNumber]RETURNS [oldNetID: NetworkNumber];GetNetworkID: PROCEDURE [physicalOrder: CARDINAL, medium: PhysicalMedium]RETURNS [NetworkNumber];NetworkNonExistent: ERROR;SpyProc: TYPE = PROCEDURE [b: BufferDefs.Buffer] RETURNS [BOOLEAN];SetSpyProc: PROCEDURE [spy: SpyProc _ NIL]; -- NIL is normal/default value.SetEthernetListener: PROCEDURE [physicalOrder: CARDINAL, newHostNumber: NSAddress.HostNumber]RETURNS [success: BOOLEAN];SetEthernetOneListener: PROCEDURE [physicalOrder: CARDINAL, newHostNumber: CARDINAL] RETURNS [success: BOOLEAN];SetEthernetCollectGarbageToo: PROCEDURE [physicalOrder: CARDINAL, collectGarbage: BOOLEAN] RETURNS [success: BOOLEAN];SetEthernetOneCollectGarbageToo: PROCEDURE [physicalOrder: CARDINAL, collectGarbage: BOOLEAN] RETURNS [success: BOOLEAN];END.  À  SpecialCommunication.mesaCopyright c 1985 by Xerox Corporation.  All rights reserved.BLyon on: February 24, 1981  2:02 PMThe router is either a plain router or an InterNetworkRouter.A network is identified by  its  PhysicalMedium and its physical location on thenetwork device chain.The router must be told which function to perform.  Function is initially  vanilla.numberINRBuffers is ignored when newFunction=vanillaRouting.This procedure returns what the router's current function is.The router/drivers may have to be told what its  network numbers are.This is certainly true if this is the first machine running on a network.Physical order is the location of the network on the network chain (starting at 1).I.E. GetNetworkID[2, ethernet] returns the OisNetID of the second ethernet networkdriver. Getting or setting a NetworkID before the network exists is an error.Hooks for Ois Peek (like Pup peek).  This invovles grabbing a system buffer from theDispatcher before it get passed to a router.  The User must inform the Dispatcher if the buffer is still usable;  if it is not then the user MUST REQUEUEthe buffer.  This can be acomplished by b.requeueProcedure[b], for buffer b.RETURN TRUE if the buffer is still to be processed by Dispatcher.RETURN FALSE if the buffer was/will be requeued by callee. These hooks are the user interface for setting addresses in the drivers.Drivers are addressed like in SetNetworkID & GetNetworkID above.Ê  ˜ codešœ™Kšœ
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