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Every device driver’s net_dev.c
Prototype
Note that since every device driver’s AddrMulticastRemove() function is accessed only by function pointer via the device driver’s API structure, it doesn’t need to be globally available and should therefore be declared as ‘static’.
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Use same exact code as in NetDev_AddrMulticastAdd() to calculate the device’s CRC hash (see NetDev_AddrMulticastAdd()), but remove a multicast address by decrementing the device’s hash bit reference counters and clearing the appropriate bits in the device’s multicast registers.
Listing A-3 Example device multicast address removal