I'm fairly new to Linux kernel programming, but have the task of developing a driver that will handle both 32-bit and 64-bit machines. To accomplish this, I believe that I must check for the CONFIG_64BIT symbol, which I also believe is made available to my module via autoconf.h. What I don't understand is whether or not that truly is the correct header, and if it is, how does the symbol get there?
I've read many articles that lead me to believe the symbols are propagated as part of the make menuconfig sequence, but nothing really lays out all of the details; just vague implications. I would like to know where things live and how they get there, so that I will know where to look when I need them in the future. Can anybody either explain this to me, or point me to some resources that will.
Thanks in advance...
I posted this question here because the issues are kernel related. If another forum (newbie, general, coffee lounge, ...) would be a better place for this question, please let me know.