Creates a CFMachPort object for a pre-existing native Mach port.
SDKs
- iOS 2.0+
- macOS 10.0+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 2.0+
Framework
- Core Foundation
Declaration
CFMachParameters
allocatorThe allocator to use to allocate memory for the new object. Pass
NULLorkto use the current default allocator.CFAllocator Default portNumThe native Mach port to use.
calloutThe callback function invoked when a message is received on the Mach port.
contextA structure holding contextual information for the Mach port. The function copies the information out of the structure, so the memory pointed to by
contextdoes not need to persist beyond the function call.shouldFreeInfoA flag set by the function to indicate whether the
infomember ofcontextshould be freed. The flag is set totrueon failure or if a CFMachPort object already exists forport,Num falseotherwise.shouldcan beFree Info NULL.
Return Value
The new CFMachPort object or NULL on failure. If a CFMachPort object already exists for port, the function returns the pre-existing object instead of creating a new object; the context and callout parameters are ignored in this case. Ownership follows the The Create Rule.
Discussion
The CFMachPort object does not take full ownership of the send and receive rights of the Mach port port. It is the caller’s responsibility to deallocate the Mach port rights after the CFMachPort object is no longer needed and has been invalidated.