14 The awk Pattern Processing Language

In This Chapter

Syntax

Arguments

Options

Patterns

Actions

Variables

Functions

Associative Arrays

Control Structures

Examples

getline: Controlling Input

Error Messages

The awk utility is a pattern-scanning and processing language that searches one or more files to see whether they contain records (usually lines) that match specified patterns. It processes lines by performing actions, such as writing the record to standard output or incrementing a counter, each time it finds a match. As opposed to procedural languages, the awk language is data driven: You describe the data you want to work with and tell awk what to do with the data once it finds it.

You can use awk to generate reports or filter text. It works ...

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