Good Habit #5: Use escape sequences to manage long input

You have probably seen code examples in which a backslash (\) continues a long line over to the next line, and you know that most shells treat what you type over successive lines joined by a backslash as one long line. However, you might not take advantage of this function on the command line as often as you can.

The backslash is especially handy if your terminal does not handle multi-line wrapping properly or when your command line is smaller than usual (such as when you have a long path on the prompt). The backslash is also useful for making sense of long input lines as you type them, as in the following example:

Listing 1. Example of good habit #5: Using a backslash for long input

~ $ cd tmp/a/b/c || \ > mkdir -p tmp/a/b/c && \ > tar xvf -C tmp/a/b/c ~/archive.tar

Alternatively, the following configuration also works:

Listing 2. Alternative example of good habit #5: Using a backslash for long input

~ $ cd tmp/a/b/c \ > || \ > mkdir -p tmp/a/b/c \ > && \ > tar xvf -C tmp/a/b/c ~/archive.tar

However you divide an input line over multiple lines, the shell always treats it as one continuous line, because it always strips out all the backslashes and extra spaces.

Note: In most shells, when you press the up arrow key, the entire multi-line entry is redrawn on a single, long input line.