Cheat sheets for the shell

Hitting Pause

What if you are not sure that you've chosen the correct command? For instances where the command will change your system, you can add the --print option to the command to prevent it from executing directly. If you want to use this option as a default, define a corresponding alias, such as

alias navi='navi --print'

and add it in your ~/.bashrc.

You also might want to use the --print option for commands that require further input before execution. For example, the Create a tar containing files task from the compression section requires two pieces of input from the user; the software prompts you for them when you click on the command. For name:, enter the desired name of the tar archive, while files: expects the path to the files you want to compress.

Once you have confirmed both entries, the tool will display the command that creates the corresponding archive (Figure 4). If you have used the --print option, navi will not execute this command, giving you the opportunity to determine if the command has the desired effect. If the command does what you expect, then copy the command and run it.

Figure 4: The command shown here for creating a tarball requires the user to enter a name and a path before the tool shows the command.

Online Cheat Sheets

Another way to use navi is to enter a command directly as an argument at launch time. For example, entering

navi search apt

will return eight commands for Debian's apt package tool. These commands do not originate from the installed navi package; instead, they come from online sources, such as cheat.sh [5], which offers additional cheat sheets (Figure 5).

Figure 5: You can use navi to integrate commands from online cheat sheets. However, you should investigate this type of command more thoroughly with --print before you take the plunge.

Integrating the Widget

You can also add navi to the shell as a widget, which helps keep the history up to date and lets you edit the command to suit your needs before running it.

To use the software as a widget, add the following line

source "$(navi widget bash)"

to your ~/.bashrc or /etc/bash.bashrc file. This lets you launch navi by pressing Ctrl+G in the future. If the keyboard shortcut is already assigned on your system, or if you want to assign a different shortcut, you can define it in /opt/navi/navi.plugin.bash.

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