Efficient Editing In The Command Line: Part 1

If you are like me, spending a lot of time in the command line, you might be looking for ways to edit the command lines more efficiently. Many interactive UNIX programs implement line editing by using GNU’s readline library. This means that all these programs, which include the different shells, Python and many others, offer the same set of keyboard shortcuts. Mastering these shortcuts is worthwhile, since you’ll be able to use them over and over again in many places.

Moving around quickly

The most basic part is to move to the place you want to edit quickly. Here are the most useful shortcuts:

• Ctrl-a – Move to the start of the line.
• Ctrl-e – Move to the end of the line.
• Alt-f – Move forward a word.
• Ctrl-f – Move forward a char.
• Alt-b – Move backward a word.
• Ctrl-b – Move backward a char.

Another very common shortcut is Ctrl-L which clears the screen and reprints the current line at the top. This is useful if you are organizing your movies library and somebody enters the room.

Cut, Paste and Undo

Here is the list of most useful shortcuts for deleting text:

• Ctrl-w – Deletes from cursor position to the previous whitespace.
• Ctrl-k – Deletes from cursor position to the end of the line.
• Ctrl-d – Deletes from current character.
• Ctrl-u – Deletes from whole line.
• Alt-d – Deletes from cursor position to the end of the current word.
• Alt-DEL – Deletes from cursor position to the start of the current word.

The deleted text can be pasted (yanked) using Ctrl-y. You can use Ctrl-_ or Ctrl-X-U to undo the last editing command.

Summary

This covers the essentials. On the next parts of this series we’ll explore the more powerful abilities of readline. Feel free to leave here questions, suggestions, or perhaps your own tips and tricks.