Linux Fu: X Command

Text-based Linux and Unix systems are easy to manipulate. The way the Unix I/O system works you can always fake keyboard input to another program and intercept its output. The whole system is made to work that way. Graphical X11 programs are another matter, though. Is there a way to control X11 programs like you control text programs? The answer to that question depends on exactly what you want to do, but the general answer is yes.

As usual for Linux and Unix, though, there are many ways to get to that answer. If you really want fine-grained control over …read more

Paul Jacob Evans


Getting Started with Blinking Lights on Old Iron

If you ever go to a computer history museum, you’ll be struck by how bland most modern computers look. Prior to 1980 computers had lights and switches, and sometimes dials and meters. Some had switchboard-like wiring panels and some even had oscilloscope-like displays. There’s something about a machine with all those switches and lights and displays that gets your hacker juices flowing. Have you ever wanted to get started in retrocomputing? Is it difficult? Do you need a lot of money? That depends on what your goals are.

There are at least three ways you can go about participating in …read more

Paul Jacob Evans

Hack Your Memory

Imagine a fire hydrant being lifted high into the air by a large helium balloon. It goes higher and higher, but suddenly gas starts to leak out of the nozzle, which makes it sound like it’s trying to talk… but with a distinct lisp. A colorful bumblebee then lands on the balloon, licks it, and says “really yum!”  Then the bee takes out its stinger and bores on to the balloon. It pops, causing the fire hydrant to come crashing down. It smashes into a military jeep causing a massive explosion… as if it had been destroyed by a car …read more

Paul Jacob Evans

How to Do Beautiful Enclosures with Custom Fiberglass

There are times when I feel the need to really make a mess. When I think of making messes with a degree of permanency, I think of fiberglass. I also really like the smell, reminds me of a simpler time in 8th grade shop class. But the whole process, including the mess, is worth it for the amazing shapes you can produce for speaker pods and custom enclosures.

Utilizing fiberglass for something like a custom speaker pod for a car is not difficult, but it does tend to be tedious when it comes to the finishing stages. If you …read more

Paul Jacob Evans

Linux Fu: Better Bash Scripting

It is easy to dismiss bash — the typical Linux shell program — as just a command prompt that allows scripting. Bash, however, is a full-blown programming language. I wouldn’t presume to tell you that it is as fast as a compiled C program, but that’s not why it exists. While a lot of people use shell scripts as an analog to a batch file in MSDOS, it can do so much more than that. Contrary to what you might think after a casual glance, it is entirely possible to write scripts that are reliable and robust enough to use …read more

Paul Jacob Evans

Fabricate Your Own Tabletop Gaming Props

Delve into the mysterious world of tabletop roleplaying games. Warhammer Fantasy Roleplay, Shadowrun, Pathfinder, Ars Magica, Vampire, whatever gets your dice rollin’ — metaphorically in the case of a diceless system. This might very well be your daddy’s D&D. If you’re not a gamer, you’re certainly familiar with the concept. People sit around a table pretending to have an epic adventure, often adding a random element with the help of dice. A map is often displayed on the table, sized for figures that show the various heroes and villains.

As a person with access to a variety of CNC machines …read more

Paul Jacob Evans

Linux-Fu: Running Commands

One of the things that makes Linux and Unix-like systems both powerful and frustrating is that there are many ways to accomplish any particular goal. Take something simple like running a bunch of commands in sequence as an example. The obvious way is to write a shell script which offers a tremendous amount of flexibility. But what if you just want some set of commands to run? It sounds simple, but there are a lot of ways to issue a sequence of commands ranging from just typing them in, to scheduling them, to monitoring them the way a mainframe computer …read more

Paul Jacob Evans