Linux Fu: File Aliases, Links, and Mappings

Have you heard it said that everything in Linux is a file? That is largely true, and that’s why the ability to manipulate files is crucial to mastering Linux Fu.

One thing that makes a Linux filesystem so versatile is the ability for a file to be many places at once. It boils down to keeping the file in one place but using it in another. This is handy to keep disk access snappy, to modify a running system, or merely to keep things organized in a way that suits your needs.

There are several key features that lend to this versatility: links, bind mounts, and user space file systems immediately come to mind. Let’s take a look at how these work and how you’ll often see them used.

Continue reading “Linux Fu: File Aliases, Links, and Mappings” Land Rush: Vanity URLs

Hurry! Carve out your homestead with a vanity URL. You can see I’ve already secured, but get in before the rest of Hackaday finds out and you can you have ‘/tom’, ‘/jane’, or ‘/zerocool’. (Don’t do it… you can be more creative than zerocool!)

Whether you already have an account, or if you want to create one right now, the next time you log into the interface will give you the opportunity to choose your vanity address.┬áLike the Oklahoma land rush, we’re sure there will be a swell of folks looking to squat on the most pristine land. So if your first name is already taken, now is the perfect time to re-invent your perfect username.

For those that need a jump start picking their slug, we want to hear your favorite screen name/handle/user alias of all time in the comments. At the risk of embarassing [Jeff Keyzer], I have to say his alias (and company name) Mighty Ohm is pretty spectacular. Can anyone beat it?

Snake-like robot can roll around in a ring

A lot of 3D printing and a many servo motors went into this snake-like robot, and it’s only about half of what [Toby Baumgartner] plans to accomplish. In this orientation the snake is rolled into a circle, and apparently some special movements in the segments allow it to roll around like this. He compares it to a tank tread without the tank attached to it. Notice that each link is rounded on the outside. When the snake opens itself up, the toothed inside of the links contacts the ground for added traction.

It looks like eventually the larger link at the bottom will be about three times as wide. This will make room for him to mount a second ring of links. The idea is that the larger link will act as the body and this can unfold itself into a quaruped. Motors that allow the segments to pivot side to side would make it something like a four-legged spider bot.

Hackaday links: Sunday January 24

Everyone Remembers Free day right? [The Ideanator’s] Bus Pirate came in such a nice red box – he decided to make it his permanent case.

[Chico] is in the middle of making a CNC, but decided to make some music with the steppers in the mean time.

What looks like an old wooden box is actually [Ludvig’s] super sweet retro arcade cabinet. Complete with a giant emergency stop red button.

Who says Legos are dead? [Carl] used them to create a simple and cheap diffraction grating projector. Including video!

[Torchris] used an Ethernet shield exactly as it was designed, sending data over Ethernet. Still a nice hack for those needing help working with Ethernet shields and Arduino.

Finally [Robert] let us know about a friends Arduino Binary Clock. But we think his elegant use of tape and a sand blaster to engrave glass is cooler.