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+[Need to write better notes.]
+
+Look for files named *386* or *FreeBSD* and you'll see what
+you need to implement for your architecture of choice.
+
+The hardest thing is probably the assembly routines: 
+src/lib9/tas-$SYSTYPE.s and src/libthread/asm-$SYSTYPE-$OBJTYPE.s.
+The former is a test and set used to implement shared-memory
+spin locks.  The latter is a stripped down setjmp and longjmp
+used to implement stack switching in the thread library.
+Also, src/libthread/$OBJTYPE.c needs to know how to set up a stack
+frame for the given object type.
+
+If you're only interested in mk and sam, you don't need to
+write any assembly to do a port.  Samterm requires everything
+though, since it uses libthread.
+