Merry Christmas, makers! We’re guessing a lot of you found Raspberry Pis under the tree this morning and are eager to start hacking around with it. Getting Started with Raspberry Pi, which I co-authored with Shawn Wallace, will be shipping very soon and is available for pre-order now. In the meantime, we’ve compiled a list of a few of our favorite quick tips that may come in handy as you explore the platform.
Some of these might be old hat to experienced Linux users, but who knows, you might also learn something new. And if you have any favorite Raspberry Pi tips that you’d like to add, we want to hear them! Please share them in the comments below.
Command line completion
You don’t have to laboriously type out long paths, filenames, and commands. Just type the first few letters and hit tab. If bash (the command interpreter, or shell) can determine what file you’re referring to, it will fill in the rest for you. If not, hit tab again it will give you a list of possibilities if there are more than one.
Bash also keeps a history of the commands you type. When at the command prompt, hit the up key to cycle through your most recent commands. Hit enter to execute the one you want.
Jumping to the beginning or end of a command
If you want to jump to the beginning of a command you’ve typed (for instance, if you’ve miskeyed something), type Control-A. To jump to the end of the line, type Control-E
Switch screens with ALT+[F1 though F6] keys
When you’re not in the graphical desktop environment, you can still multitask. Switch between terminal screens by pressing the ALT key along with F1 through F6.
It can be frustrating to type out an entire command only to be told you need to be the superuser to execute it. Type “sudo !!” (pronounced “sudo bang bang”) to execute the previous command as root.
Install scrot (by executing “sudo apt-get install scrot”) so that you can take screenshots within the graphical desktop environment. After it’s installed, execute the command scrot in a terminal window to save a PNG of the desktop to the working directory. Scrot is also highly configurable; execute “scrot -h” to see all the options available to you.
Log in remotely
If you want to access your Raspberry Pi’s command line from another computer, type sudo raspi-config at the prompt and choose the option to enable SSH. Then type ifconfig to get your Raspberry Pi’s IP. On a OS X or Linux computer, type ssh pi@[ip address] to connect to your Pi. On Windows, use PuTTY.
Use your computer’s internet connection
If you don’t have a convenient ethernet connection nearby or a USB Wifi adapter handy, you can also use your computer’s Wifi internet connection and share it via Ethernet to the Raspberry Pi. Here are guides to do on various operating systems: Mac OS, Windows, or Linux (Ubuntu).
One line Python web server
If you’d like to create a web server with just one command, simply execute “python -m SimpleHTTPServer”. The files in the current working directory will be accessible via your Pi’s IP address. Add an index.html file if you’d like to serve that page, otherwise, a file directory will be displayed. In Getting Started with Raspberry Pi, we show you how to set up a more advanced, dynamic web server that can even read sensors or control things in the real world.
If you have trouble remembering the IP address of your Raspberry Pi when you want to access it over the network, install avahi with the command “sudo apt-get install avahi-daemon” and you’ll be able to use raspberrypi.local instead of the IP address. If you’re accessing the Raspberry Pi from a Windows machine, you may need to install Bonjour Services on it for this to work.
There are plenty more tips like these in Getting Started with Raspberry Pi, which will start shipping any day now. The ebook is available for download now in the O’Reilly shop (DRM-free), on Amazon, and in the iBook store.