CHAPTER 6Invocation and Execution
This chapter discusses the runtime of the shell. The shell must be started in some way; this is discussed in the next section, "Shell Invocation." Once the shell is running, it is important to understand what the shell actually does, the order in which substitutions occur, and the way the shell interacts with other processes. It may even be necessary on rare occasions to use additional tools to debug a script that behaves unexpectedly.
This section discusses the process of starting the shell (or a shell script) and telling it what to do; this is called invocation. The shell itself is a command, like any other, which takes command-line options and arguments; similarly, each shell script becomes ...