PATH
The routines described in this section deal with interrupt sets. CreateInterruptSet extends an IST by creating a new interrupt set. GetInterruptSetOptions helps an expert determine how the interrupt dispatcher will handle an interrupt set, and ChangeInterruptSetOptions helps it change that behavior.
The Mac OS IST for PCI cards is initialized and activated by Apple software. Third-party I/O software needs only to update member functions as necessary to support PCI cards. Extending the IST is required only for multifunction cards and bridges that don't use the default PCI bridge IST extensions.