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+This directory contains "alternative" versions of some pieces of the system. 
+
+Things included here:
+
+    Make.mk
+        This version of the Makefile fragment puts the utility programs
+        in build/util instead of in the top-level directory.
+
+    kmem.c
+        A version of the memory allocator that works with blocks of memory
+        that aren't exactly one page in length. During initialilzation, it
+        just adds each memory region identified during the boot process by
+        calls to the BIOS; as pages are requested, they are carved out of
+        these large blocks. The freelist is ordered by starting block
+        address, and allocation uses a first-fit strateby.
+
+        The allocation function has this prototype:
+
+            void *km_page_alloc( unsigned int count );
+
+        This allows the allocation of multiple contiguous pages. As pages
+        are freed, they are merged back into the freelist, and adjacent
+        free pages are coalesced into single, larger blocks.
+
+    lib.c
+        This file pulls in all the individual .c files for the common
+        library functions in the lib/ directory. It is intended as an
+        alternative to having the libk.a archive file for the kernel;
+        instead of linking against that library, the lib.o file can
+        just be provided to the linker when the kernel is created,
+        and all the common library functions will be available.