Unix Shell Programming, Third Edition

4. Tools of the Trade

In This Chapter

• Regular Expressions

• cut

• paste

• sed

• tr

• grep

• sort

• uniq

• Exercises

This chapter provides detailed descriptions of some commonly used shell programming tools. Covered are cut, paste, sed, tr, grep, uniq, and sort. The more proficient you become at using these tools, the easier it will be to write shell programs to solve your problems. In fact, that goes for all the tools provided by the Unix system.

Regular Expressions

Before getting into the tools, you need to learn about regular expressions. Regular expressions are used by several different Unix commands, including ed, sed, awk, grep, and, to a more limited extent, vi. They provide a convenient and consistent way of specifying patterns to ...