> And that *is* the point. All your "0" and "NULL" above are the C source > representation independent of the bitmap used on the hardware at > run-time. And it must always work. this has nothing to do with run-time. this macro calculates the offset at compile time. AGAIN, i see NO relevance to the actual representation of NULL in hardware. as i understand this, this is just a compiler trick, to get an offset. if im terribly mistaken, can someone please enlighten me ???? -- ======================================================================== nir. -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/