The Software Developer's Guide to Linux

11

Pipes and Redirection

In this chapter, you’re going to learn how to harness one of the most powerful computing concepts in existence: pipes! Pipes can be used to connect commands, building up complex, customized flows that accomplish a specific task. By the end of the chapter, you’ll be able to understand (or compose) something like this:

history | awk '{print $2}' | sort | uniq -c | sort -rn | head -n 10

In case you’re curious, this prints out a top-10 list of your most commonly used shell commands; on my machine, it produces this output:

1000 git
 115 ls
 102 go
  83 gpo (an alias I've set up for pushing a local git branch to the origin)
  68 make
  65 cd
  59 docker
  42 vagrant
  35 GOOS=linux
  30 echo

To really understand pipes, you need to first ...