Retired Document

Important: The information provided in this document is relevant for Mac OS 10.1 through 10.3. Specific mention is made for items which apply to newer releases of the OS.

An important change has long been noted in the <sys/mbuf.h> header file since the release of Mac OS X 10.2. Note that the header file is bracketed by the __APPLE_API_UNSTABLE define. The mbuf structure is a key to the processing of packets in an NKE. As part of the formalizing the NKE APIs, it is expected that the mbuf structure will be changed. Details will be provided in the future. Changes to the existing NKE API are not expected be applied to System Updates to Mac OS X 10.3.x, however, bug fixes or features for future systems may require some interim changes.

For all shipping releases of Mac OS X prior to 10.4, the Network Kernel Extensions (NKE) APIs have not been officially supported. The legacy NKE architecture was implemented as an interim solution. The legacy API was never designed to be officially supported. Other aspects of the OS X networking implementation have received a higher priority, and so the interim solution has remained in effect to OS X 10.3.x.

The NKE mechanism for Mac OS X version 10.4 and later is described in the document Network Kernel Extensions Programming Guide.