Case insensitive tab completion in Bash

Question

Is there any way to make Bash tab complete case insensitively?

$ bash --version
GNU bash, version 3.2.48(1)-release (x86_64-apple-darwin10.0)
Copyright (C) 2007 Free Software Foundation, Inc.

I am using Mac OS X 10.6

Solution 1

Update the text in /etc/inputrc to include

set completion-ignore-case on

Then use ^X ^R to reload the configuration.

Solution 2

^{Restructured with the benefit of hindsight to contrast the pros and cons of using [.]inputrc vs. .bash_profile.
Tip of the hat to underscore_d for his help.}

Note: Command-line editing in Bash is provided by the Readline library; customizing it is non-trivial, but well worth learning; its features include the ability to define custom keyboard shortcuts for inserting predefined snippets of text - see Command Line Editing in the Bash Reference Manual

To persistently make tab-completion case-insensitive in Bash:

---

Option A: If you either already have:

• an /etc/inputrc file (applies system-wide, modification requires sudo)

• and/or a ~/.inputrc file (user-specific)

  and/or

you're planning to customize the readline library extensively and/or want to make customizations effective for scripts too when they call read -e:

Add line

set completion-ignore-case on

to either file, depending on whether you want the setting to be effective for all users or the current user (create the file, if necessary).

A related command that makes completion of file and directory names easier is:

set show-all-if-ambiguous on

This makes it unnecessary to press Tab twice when there is more than one match.

---

Option B: Alternatively, you may add Readline commands to your user-specific ~/.bash_profile file on OS X (or ~/.bashrc on Linux), by passing them as a single argument to the bind builtin:

bind "set completion-ignore-case on"
bind "set show-all-if-ambiguous on"

Note that bind commands in ~/.bash_profile / ~/.bashrc take precedence over equivalent commands in either /etc/inputrc or ~/.inputrc.

As implied above, Readline configuration defined this way will not take effect in scripts that call read -e to activate Readline support for reading user input.

Solution 3

To avoid changing configuration for all users and to avoid root permissions use the following:

if [ ! -a ~/.inputrc ]; then echo '$include /etc/inputrc' > ~/.inputrc; fi
echo 'set completion-ignore-case on' >> ~/.inputrc

Then re-login or reload ~/.inputrc

Comments

[Dennis Williamson]

"as well" - /etc/inputrc or ~/.inputrc or a file designated by INPUTRC are the only places it can go. Entering that at a Bash prompt won't work.

[John T]

whoops! you're right :)

[user1686]

^X ^R to reload inputrc

[Clay Bridges]

@DennisWilliamson: you can do bind "set completion-ignore-case on" from the command line; for, I believe, that terminal session only

[user34112]

show-all-if-ambiguous is so nice! I often wondered why they made me tab twice to perform that action. thousands of keystrokes saved in my future! thanks!

[Alex Shroyer]

Awesome, it even works for cd commands. Which solves this question and will be saving me thousands of keystrokes too. :)

[SamB]

So that's what msysgit has but MSYS2 lacks! Here I was trying to find it in e.g. /etc/profile ...

[underscore_d]

Great point re show-all-if-ambiguous. However, since you say "as an alternative", is there actually any benefit to doing this via bind, when the inputrc files seem to make that unncessary?

[mklement0]

@underscore_d: Good question; please see my updated answer.

[underscore_d]

Cool, thanks! On Debian 8.2 I had neither inputrc, but I happily created ~/.inputrc & added these, plus other really useful directives. I guess we're assuming all readers know that /etc/inputrc affects other users (unless the latter override the affected settings)? Just while we're mentioning caveats ;)

[underscore_d]

I think that covers everything - thanks for your efforts making a great answer even better!

[Exocom]

Writing this to ~/.inputrc breaks the ctrl key functionality. Or am I the only one with this problem?

[Liker777]

if not successful with reload the configuration, can just restart bash

[StatsScared]

I'm on macOS and new to bash. How exactly does one "Update the text in /etc/inputrc" ?