Other System Tools

In this and the prior chapters, we've met most of the commonly used system tools in the Python library. Along the way, we've also learned how to use them to do useful things like start programs, process directories, and so on. The next two chapters are something of a continuation of this topic -- they use the tools we've just met to implement scripts that do useful and more realistic system-level work, so read on for the rest of this story.

Still, there are other system-related tools in Python that appear even later in this text. For instance:

• Sockets (used to communicate with other programs and networks) are introduced in Chapter 10.
• Select calls (used to multiplex among tasks) are also introduced in Chapter 10 as a way to implement servers.
• File locking calls in the fcntl module appear in Chapter 14.
• Regular expressions (string pattern matching used by many text processing tools) don't appear until Chapter 18.

Moreover, things like forks and threads are used extensively in the Internet scripting chapters: see the server implementations in Chapter 10 and the FTP and email GUIs in Chapter 11. In fact, most of this chapter's tools will pop up constantly in later examples in this book -- about what one would expect of general-purpose, portable libraries.

Last but not necessarily least, I'd like to point out one more time that there are many additional tools in the Python library that don't appear in this book at all -- with some 200 library modules, Python book authors have to pick and choose their topics frugally! As always, be sure to browse the Python library manuals early and often in your Python career.