You may be wondering where I am, given that I haven’t posted a Contra entry for over a month. I didn’t want May to conclude with zero entries posted, so I figured I’d take a break here and get you up to speed.
Here’s the deal: My publisher has asked for a Fourth Edition of Assembly Language Step-By-Step. It’s been thirteen years since the Third Edition came out, so it’s well past time. The idea here is to bring the book up to date on the x64 architecture. In fact, so that no one will mistake what’s going on, the title of the new edition will be x64 Assembly Language Step-By-Step, Fourth Edition. Whether they keep the “x” in lowercase remains to be seen.
So I’m off and editing, writing new code and checking every code snippet in a SASM sandbox, and making sure that I don’t forget and talk about EAX and other 32-bits-and-down entities without good reason. (There are good reasons. Even AH and AL are still with us and used for certain things.) Make no mistake: This is going to be a lot of work. The Third Edition is 600 pages long, which isn’t the longest book I’ve ever written (that honor belongs to Borland Pascal 7 From Square One, at 810 pages) but it’s right up there.
My great fear has been the possibility of needing to add a lot of new material that would make the book even longer, but in truth, that won’t be a huge problem. Here’s why: Some things that I spent a lot of pages on can be cut way back. Good example: In 32-bit Linux, system calls are made through the INT 80H call gate. In the Third Edition I went into considerable detail about how software interrupts work in a general sense. Now, x64 Linux uses a new x64 instruction, SYSCALL, to make calls into the OS. I’m not completely sure, but I don’t think it’s possible to use software interrupts at all in userspace programming anymore. I do have to explain SYSCALL, but there’s just not as much there there, and it won’t take nearly as many words and diagrams.
Oh, and of course, segments are pretty much a thing of the past. Segment management (such that it is) belongs to the OS now, and for userspace programming, at least, you can forget about them. I’m leaving a little description of the old segment/offset memory model for historical context, but not nearly as much as in previous editions.
I also dumped the Game of Big Bux, which doesn’t pull its weight in the explanation department, and isn’t nearly as funny now as it was in 1990. But have faith: The Martians are still with us.
My guess is that from a page count standpoint, it will pretty much be a wash.
It’s going to take me awhile. I don’t know how long, in truth. Especially since I am going to try to keep my fiction output from drying up completely. The book will slow me down, but (for a change) the publisher is not in a huge hurry and I think they’ll give me the time I need. I have 56,000 words down on The Everything Machine, and don’t intend to put it on ice for months and months. I’m not sure how well that’s going to work. We’ll see.
