Chapa 1)


The eev Manifesto


Do you remember your first Unix days, when you were always asking yourself questions like "how do I compile this?", "how do I install this stuff?", "and now, how do I run it?", "how do I generate html from this file?"?

Do you remember how you marvelled at the first time you ran a "make" on a package and you saw echoed each of the commands that were used to generate binaries and docs from the source? Have you had the same feeling I've had, that by understanding those commands we would have access to the tricks that the owner of the package knew, and that we'd learn which were the "important" programs and in what way the experts used them?


Everybody is fluent in only a small fraction of all Unix commands. If you could "listen" to how the Unix gurus "speak" to their machines you would learn which "words" are related to solving a particular task, and learn how they fit in "sentences". By checking the "dictionary entries" for them (i.e., manpages, info pages, READMEs, source code, etc) you could learn the real meaning of them. But then you'd be learning Unix by immersion, from real use, instead of having to rely only on "textbooks", "dictionaries" and sometimes "Rosetta stones", "graffitis on toilet walls" and "old newspapers".

The fact is that you can make a record of how you "speak" Unix, and more, you can become a lot more productive if you do so. Many tasks consist on short fixed sequences of commands: connecting to your ISP via modem, unpacking a source package and recompiling it, printing a text file in two-column mode, and so on. The trick is that with some functions defined in eev.el you can write these sequences of commands in a plain text file, then mark a block of this file with your editor (which must be Emacs for this to work), then tell a shell to execute only the commands in that block; in this way you can easily execute only portions of what would otherwise have to be a monolythic script; this is great for when you're not sure if everything works, or if you just want to do some steps. Also, it would be easy to change bits of the "script" before execution, as you'll be doing things from inside an editor.

There is also another trick. Scripts allow "comments", that is, lines that are not executed; generally the convention is that lines that start with "#" are comments. So we can place lines like these in a script:

# (find-enode "Picture" "C-c c-c")

The expression "(find-enode "Picture")" is an Emacs command (in Lisp) that means: open the "info page" called "Picture", from the Emacs manual, treating it as a file; then place the cursor after the first occurrence of the string "C-c c-c" there. To execute this command, i.e., to make emacs go to that point on that page, you just have to put the cursor after the ")" and type C-x C-e. There are many other similar commands, that will open specific files or specific manpages, with various ways of searching. These "hyperlinks" are especially interesting if you want to record from where you got some piece of information relevant to the "script" you're writing; this is very useful, for example, on "scripts" you haven't finished and on which you plan to work more someday, or on scripts you want to send to someone.

Just as hyperlinks have many flavors, the function that executes a block also has variants: a block can be executed by the Tcl interpreter instead of the shell, or can be run through LaTeX, just to pick some examples. See the docs on eev.el.


I have placed essentially all my "scripts" written in this way (I call them "e-scripts") in a public place. They contain almost everything I know about Unix.

If you like this idea, please get in touch, send comments, ask questions -- about e-scripts or questions whose answer could become an e-script chunk -- or send me your e-scripts when you have some, or even ask for help on setting up your own e-script collection or e-script public site... anything! By asking good questions you can help me make the documentation get better.

I really want to make this e-scripts idea spread. Learning Unix -- or simply more Unix -- could be made easier for everybody... please help! E-scripts are more fun to use, and easier to write, than texts that tell everything in terms of "press this, do that". A lot of effort and money are being invested now on these kinds of text, and they're often very depressing. Let's try to save the world from them, at least a bit, and maybe this money will be directed to better things. And teaching people Unix tricks will be both easier and more fun.

Eduardo Ochs, 1999dec18.