Re: linux-kernel-learning

[Rick Hohensee]

Two things have been huge revealers of what these guys are talking
about since I've been trolling this list. One is "The Design of the
UNIX Operating System", Maurice J. Bach, Prentice Hall, 1986? 
Linus has mentioned that book. Linus recommends a book, I go get it.
One, anyway. It's the "K&R of unix", with an AT&T
copyright, authoratativeness, and price. But worth it. There is some
mention in there of almost everything in current Linuces. The major
features I don't recall mention of in there are modules and journalling,
but the basic issues of SMP and so on are discussed.

The other is 80386 assembly. The x86 is a market-driven CPU design, and
the holy grail of the microprocessor market has been UNIX. There's a lot
of things I thought were entirely software in Linux that are supported by
386+ hardware. Not surprisingly, linux-kernel tends toward the 386 terms 
for these things. The difference between an OS and a plain program is 
reflected in the difference between the 386 instruction set and what one  
can reasonably do in C. C doesn't have any concept of global descriptor 
tables and such. It assumes someone like Linus has already done all that
crap for you. 

Anyway, even if not the x86, learn a big-chip assembler. The 8086 legacy
stuff in the 386 does NOT impinge on Linux (well, ELKS maybe). An OS is 
between C and the hardware. This isn't top-down stuff. The asm in Linux is 
kept to a minimum, but the rest of the OS is built on the asm. 

Rick Hohensee