Sed and awk by Dale Dougherty

This resource serves as a comprehensive guide to sed and awk, two powerful command-line utilities for text processing. It explores their origins, basic operations, and advanced functionalities, including pattern matching with regular expressions, file manipulation, and scripting. The text also details system variables, functions (arithmetic and string), and various implementations of awk (Bell Labs awk, GNU awk, mawk, tawk, VSAwk), alongside debugging strategies and practical examples for tasks like report generation and data extraction. Additionally, it provides information on accessing program examples via FTP and UUCP, and covers POSIX standards relevant to both sed and awk.