Interactive Scripts
Core Technology
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Some shell scripts are silent; others communicate to users extensively. Learn how to make their dialog smoother with, er … , dialogs.
As an administrator, you may view shell scripts as wordless minions that do their job and die silently – unless an error occurs, of course. At least, that's what we expect from a well-behaving Unix command. There are good reasons for that (think pipelining), but it doesn't mean you must have it that way all the time.
In this Core Tech, we'll learn some tricks to make shell scripts interact with the user via command prompts and dialog boxes. This is how you got Slackware installed, right? (You did try Slackware, didn't you?) Yes, the Slackware installer is basically a shell script, and with some tools under your belt, you can do no worse than Patrick Volkerding. Sound good? If so, let's go and have some text-mode fun.
Command Prompt
Perhaps the simplest form of interactivity you can have in your scripts is a command prompt. That's how shell itself is made interactive, after all. Getting pieces of data from the user is possible with the read
built-in command [1]. But, to make things fancier, let's throw some history support and other readline goodies into the mix.
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