Code Foundation has a few programming-interface conventions in addition to those related to opaque types and memory management.
CFIndex
type is used for index, count, length, and size parameters and return values. The integer value this type represents (currently 32 bits) can grow over time as the processor's address size grows. On architectures where pointer sizes are different, say 64 bits,
CFIndex
might be declared to be 64 bits, independent of the size of
int
. By using
CFIndex
for variables that interact with Core Foundation arguments of the same type, you ensure a higher degree of source compatibility for your code.
CFPropertyList.h
. CFPropertyList is a placeholder type for any of the property-list types: CFString, CFData, CFBoolean, CFNumber, CFDate, CFArray, and CFDictionary.
NULL
. This indicates that the caller is not interested in that return value.