An Illustrated Guide to Shell Magic: Standard I/O & Redirection

machines_connected

We’ve been spending some time on Raspberry Pi meta-topics lately, so to speak, building kernels and packaging software for Raspbian Machines, projects which will hopefully make other projects easier. I got a bit distracted from the project of writing guides introducing the Pi’s environment. Here’s the latest, on some basic shell magic:

Now that we’ve covered some basic shell commands, let’s shift focus a little and talk about some of the features that bind those commands together into a useful working environment. In this guide, we’ll cover:

  • standard input and output
  • combining commands with pipes
  • redirecting output to and from files
  • standard error and exit codes

While these may sound like dry topics, it’s here that the command line begins to come into its own as a tool and environment for solving problems. Pull up a terminal and read on!

As ever, feedback on these would be much appreciated.


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