The kernel support library, libkern.a, supplies a variety of functions and other definitions that are primarily of use in OS kernels. (In contrast, the other parts of the OSKit are more generic components useful in a variety of environments including, but not limited to, OS kernels.) The kernel support library contains all the code necessary to create a minimal working ``kernel'' that boots and sets up the machine for a generic ``OS-friendly'' environment. For example, on the x86, the kernel support library provides code to get into protected mode, set up default descriptor tables, etc. The library also includes a remote debugging stub, providing convenient source-level debugging of the kernel over a serial line using GDB's serial-line remote debugging protocol. As always, all components of this library are optional and replaceable, so although some pieces may be unusable in some environments, others should still work fine.