Book Review: Autotools by John Calcote

You probably know how I feel about Autotools books given I actually wanted to write one, was mostly rejected, and ended up working on spare time on Autotools Mythbuster — which I really should write more on. Definitely the “Autobook” needed a rehash, that was obvious. The spot was taken not by me but instead by John Calcote, with his Autotools: A Practical Guide To GNU Autoconf, Automake, And Libtool — okay I’m a bit envious of that, but not excessively.

At any rate, No Starch Press has been tremendously kind and offered me a review copy – I did contact them to propose my guide as a book, and they did tell me they had a book already in the works.. John’s – which I accepted gladly. I actually hoped to post the review much sooner, but between job tasks, and Gentoo messes, time was a rare commodity. And to be honest, it felt a lot like reading a textbook when you know already the subject. Don’t get my tone wrong. I find John’s work very stimulating: for a newcomer to the world of build systems, it definitely goes in much deeper detail than most documents I’ve seen before; he also does something that I strive for myself: described all the related topics: make, autoconf, automake and libtool, plus a number of related, but not directly-involved, topics.

For instance, he goes into two important topics that I have only written about in the blog up until now — Position Independent Code and library versioning — and then provides a whole chapter dedicated to tip and tricks, not only tied to Autotools. Some of the tricks were new also to me, and I’ve been floating in this topic for the best part of the past seven years (even before I joined as a Gentoo developer). Some further insights also show that he’s not tied to the Unix world itself, which is always a positive thing, as a lot of time we self-validate ourselves and can’t think outside that limited box.

Given these properties, I couldn’t find any reason not to list it on the further readings section of my own guide.

I could stop here with the review, and possibly make John and No Starch pretty happy, but I’d feel like I “sold” myself for the hope to actually keep a good contact with them as a publisher. But it wouldn’t be right for them either; I owe them my full opinion. Thus, I have now to move a few personal grudges I have with John’s approach, without reducing the sheer importance that this book has for all of us developers of Free Software that work with autotools daily: he stuck too much with the point of view of the Autotools’ upstream maintainers.

Don’t get me wrong, it’s obvious that diverting from the authors’ intention for any kind of software is bad, but I have fiercly criticized them before about their failure to get to agree to what should be used together. They insist that autoconf and libtool can be used standalone, without automake at all, they provide a number of support macros, but not all those you’d be expecting them to, and so on so forth. All these things actually make me pretty sad, and that’s why I’m trying my best on my text to actually write of a complete build system, using all three of them, plus pkg-config, which John mentions just in passing in the book, and that, as usual I’ll add, feels like a bastard child of the rest of the projects.

It actually pours more than just at that level; while he acknowledges the (must read) Recursive Make Considered Harmful by Peter Miller, he then states (I quote) “[T]he sheer simplicity of implementing and maintaining a recursive build system makes it, by far, the most widely used form of build system.” – Well, I cannot dispute the fact that it is the most widely used form; I can definitely argue a lot about the “simplicity”, especially considering that recursive build systems have atrocious support for parallelisation, and with modern machines growing more in number of cores (or execution threads) than they do in pure speed, that is an important detail to consider; especially for big projects.

Another thing that baffled me is that John is able to describe the Autoconf Archive without moving a comment about the policies regarding bundled and non-bundled macros in autoconf … add to that the way he dismisses most of the mistakes in the official documentation, or the idiosincratic behaviour of some macros, and that is what I call “siding with the authors” (by itself, of course, there is nothing wrong; he’s much more objective than I could ever be I guess). For those who want to take a laugh now, John’s book refers to the Autoconf Archive website; the Autoconf Archive website then links back to Autotools Mythbuster. Heh.

It can be opinable I guess, but for me, despide its subtitle defines it as a “Practical Guide”, I find it a good theoretical textbook; but I disagree that you should be using Autotools the way they are describe by John, or by the official documentation for what matters; like it or not, a lot of the technical decisions in those projects are taken after a political stance, and that shows on some recommendations that to me only hinder development and adoption of the tools. And in the current landscape where cmake is still preferred to build under Windows, and, luckily for all of us, scons is finally disappearing, dropping the politics, and simply provide a good pragmatic approach to practice is what I was hoping for.

Final words and sound bite/quotable opinion? John’s is an important book, as I already noted. It shows a stirring ecosystem of people working around Autotools; even though we disagree on views and in some technical details, his is the only current and complete text on the tools of the trade. If you’re a newcomer who want to know how it works behind the scenes in detail, you just have to read it. But if you’re interested in writing a good build system by modern standard, you cannot just stop here. John is showing you the door; but you’ve got to walk through it and proceed to the end of the corridor… deciding which further doors to peek into, and which ones to keep shut.