On Sat, Oct 14, 2017 at 6:32 AM, Peter J. Holzer <hjp-usen...@hjp.at> wrote: > On 2017-10-13 14:51, Chris Angelico <ros...@gmail.com> wrote: >> On Sat, Oct 14, 2017 at 1:32 AM, Steve D'Aprano >><steve+pyt...@pearwood.info> wrote: >>> It seems to me that you're not talking about ROM at all, but ordinary RAM. >>> Then what do you mean by "read only"? A block of memory with a flag that >>> says "unprivileged processes are prohibited from writing here"? >>> >>> (That's also not a rhetorical question.) >> >> When I first learned about Protected Mode (as defined by the Intel >> 80386 and used in OS/2), there was a real concept of read-only RAM. >> The program loader would fetch up the executable file (data on the >> disk) and construct its segments: code, data, and BSS/stack. > > This is still the case. The granularity is just finer now: Instead of > segments you use pages. (The 386 was the first x86 processor which > supported paging. OS/2 probably used segments because it was originally > designed for the 286.)
... either that, or I'm just misremembering, it being many MANY years since I did anything that low-level. Let's assume I was mistaken. :) ChrisA -- https://mail.python.org/mailman/listinfo/python-list
