Unix Power Tools, 3rd Edition

Chapter 24. Starting, Stopping, and Killing Processes

What’s in This Chapter

Summary Box

We’ve already talked about so many of the topics in this chapter, here or there, that it may seem like a real hodgepodge. It’s a grab-bag of important things to know about processes — which you can think of as programs that are actually running, rather than sitting on the disk somewhere.

The chapter starts out with a couple of conceptual articles. They define some important terms that you’re likely to encounter in this chapter.

Then we talk about the ps command, which tells you what processes you have running and just what they are up to (Section 24.5, Section 24.6, Section 24.8).

The next few articles cover signals, which are one way processes communicate with one another. We cover topics like:

• What are signals (Section 24.10)?

• How to send signals from the keyboard (Section 24.11 and Section 24.12; also see Section 5.8).

• How shell programs can “handle” signals (Section 24.13 and Section 35.17).

We go from there to a more general discussion of ways to kill processes:

• How to kill all your processes (Section 24.14).

• How to kill processes by name rather than by process ID (Section 24.16).

• How to stop runaway jobs (Section 24.17).

• Why some processes don’t seem to go away when you kill them (Section 24.18, Section 24.19).

• How to get rid of a frozen window (Section 24.22).

• How to make sure processes don’t die when you log out (Section 23.10).

— TOR

fork and exec

We discuss fork and exec in Section 27.2, but the ...