Bash Productivity Enhancers

Bash is an extremely powerful shell, but its shortcuts are not readily apparent. Here are a few shortcuts and tips that I’ve noticed many (already proficient) bash users are not aware of. You can also check out Improved Bash History and More Useful Bash/Terminal Settings for more ideas for improving your bash productivity.

Bash Navigation Shortcuts

When editing a long command, there are quite a few navigation and editing shortcuts. By default bash typically operates in emacs mode.

• Ctrl-A to go to the beginning of the line

• Ctrl-E to go to the end of a line.

• Ctrl-W will cut the current word (searching backward)

• Ctrl-U will cut everything before the cursor

• Ctrl-K cuts everything after the cursor

• Ctrl-Y pastes the last text that was cut

• Ctrl-T swaps the order of the last two characters entered¹

• Meta-B will move the cursor back one word

• Meta-F will move the cursor forward one word

Meta keys are a bit tricky since they can differ based on your terminal application. On Windows/Linux it is typically Alt and on Mac OS X Terminal.app defaults to using Esc (but you can change it to option/alt in the preferences).

However, bash also has a vi/vim editing mode. To enable this type “set -o vi”. At this point all the typical vi shortcuts are available if you enter command mode (by hitting Esc). I don’t recommend using this unless you are very comfortable with vi already.

reverse-i-search

You can search through your history and rapidly find a command used previously with reverse-i-search. To invoke, press Ctrl-R and start typing. If you have multiple matches, hit Ctrl-R to cycle through them all. When coupled with an improved bash history this is an extraordinarily useful tool.

Controlling Tasks in Bash

Bash allows you to stop, background, and foreground tasks. To background a process before it starts simply add & to the end of your command.²

mycommand &
[1] 1922

If you have an already running task and you’d like to stop it press Ctrl-Z. This task will obtain a job number (the number in brackets).

[1]+  Stopped                 mycommand

You can then resume the task in the foreground with fg # or background it with bg #. To see a list of jobs that have been backgrounded or stopped type jobs.

Redirecting stderr/stdout in Bash

Bash has two main output buffers: stderr and stdout. Both of these, by default, output to your terminal window.

• To redirect stdout to a file add > /path/to/output

• To redirect stderr to a file add 2> /path/to/output

• To redirect stderr into stdout add 2>&1