This is xnu-8019. See this file in:
Directory listing for xnu-8019//libsyscall/mach/mach
errorlib.h
mach.h
mach_error.h
mach_init.h
mach_interface.h
mach_right.h
mach_right_private.h
mach_sync_ipc.h
port_descriptions.h
port_obj.h
sync.h
thread_state.h
vm_page_size.h
vm_task.h