4. Summary

In this chapter we learned how commands can be linked to each other, and how input from one command can be used as output for another command.

Input/output redirection is a common task on UNIX and Linux machines. This powerful mechanism allows flexible use of the building blocks UNIX is made of.

The most commonly used redirections are > and |. Refer to Appendix C, Shell Features for an overview of redirection commands and other shell constructs.

Table 5.1. New commands in chapter 5: I/O redirection

CommandMeaning
dateDisplay time and date information.
setConfigure shell options.
sortSort lines of text.
uniqRemove duplicate lines from a sorted file.