CHAPTER 2Input, Output, and Throughput
Two of the commands we used in Chapter 1 are workhorses of the shell scripter's stable: echo
and printf
. Both are bash
builtin commands. Both print information to the standard output stream, but printf
is much more powerful, and echo
has its problems.
In this chapter, I'll cover echo
and its problems, the capabilities of printf
, the read
command, and the standard input and output streams. I'll start, however, with an overview of parameters and variables.
Parameter and Variables
To quote the bash
manual (type man bash
at the command prompt to read it), "A parameter is an entity that stores values." There are three types of parameters: positional parameters, special parameters, and variables. Positional ...
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