Pipes and Redirection

Part of the Linux course

In the last lesson you built small pipelines with | almost in passing, sending the output of one text tool into another. It is time to slow down and look at what that character is actually doing, because it is not special syntax just for grep and awk. Every single command you run in Linux, without exception, has three data streams attached to it: one it reads input from, one it writes normal output to, and one it...

Give a command a name and you would probably describe what it prints. But under the hood, every command is connected to three separate channels. stdin ("standard in") is where a command reads input from, by default your keyboard. stdout ("standard out") is where a command writes its normal, successful output, by default your screen.