osx man page for ioclasscount

IOCLASSCOUNT(8) 					    BSD System Manager's Manual 					   IOCLASSCOUNT(8)

NAME
     ioclasscount

SYNOPSIS
     ioclasscount [classname] [...]

DESCRIPTION
     ioclasscount displays the instance counts of OSObject-based C++ classes in the kernel, incremented by the number of direct subclasses that
     have an instance count of at least 1.  For example, if IONetworkController is not directly instantiated, but its direct subclass IOEthernet-
     Controller has any instances, then IONetworkController's instance count will be at least 1; if another direct subclass such as IOFWController
     has any instances, then IONetworkController's instance count will be at least 2; and so on.  (This modification of instance counts prevents
     unloading of kexts defining superclasses that have no instances, but whose subclasses in other kexts have instances.)

     If classes are specified, instance counts are printed as a comma-separated list in the order specified.  If no classes are specified,
     instance counts for all classes are printed, one per line of output and sorted by name.

     This information is useful for tracking leaks.  Instance counts can also found in the root of the IORegistry in the ``IOKitDiagnostics''
     property.

EXAMPLES
     Display instance counts for IOPCIDevice and AppleTestPCI:

     /usr/sbin/ioclasscount IOPCIDevice AppleTestPCI
	    IOPCIDevice = 2, AppleTestPCI = 1

SEE ALSO
     ioalloccount(8), ioreg(8)

Darwin								 November 06, 2008							    Darwin