556

Suppose I have an alias in the bash shell. Is there a simple command to print out what command the alias will run?

6 Answers 6

730

The type builtin is useful for this. It will not only tell you about aliases, but also functions, builtins, keywords and external commands.

$ type ls
ls is aliased to `ls --color=auto'
$ type rm
rm is /bin/rm
$ type cd
cd is a shell builtin
$ type psgrep
psgrep is a function
psgrep () 
{ 
    ps -ef | { 
        read -r;
        printf '%s\n' "$REPLY";
        grep --color=auto "$@"
    }
}

type -a cmd will show all the commands by that name in order of precedence, which is useful for the ls alias above, where the alias itself calls ls.

$ type -a ls
ls is aliased to `ls --color=auto'
ls is /bin/ls

This tells you that when you run ls, /bin/ls will be used, and --color=auto will be included in its list of arguments, in addition to any other you add yourself.

7
  • 1
    what to do when an alias contains MORE aliases?
    – user251046
    Commented Jul 26, 2014 at 10:34
  • 3
    @user251046 keep using type until you hit something other than an alias ...
    – geirha
    Commented Sep 3, 2014 at 19:03
  • I like this answer because type will parse/interpret any quotes, so you can make sure the quotes are right.
    – wisbucky
    Commented Mar 2, 2018 at 4:21
  • I got ls is aliased to 'ls --color=auto', but how can I get one layer deeper, to see whether it uses /bin/ls or /usr/local/bin/ls or what?
    – krubo
    Commented Jan 29, 2019 at 2:19
  • 5
    @krubo type -a ls will show all ls commands found in order of preference. Whichever is right below the alias is the one that will be executed by the alias.
    – geirha
    Commented Jan 30, 2019 at 7:54
246

Just type alias while at the Shell prompt. It should output a list of all currently-active aliases.

Or, you can type alias [command] to see what a specific alias is aliased to, as an example, if you wanted to find out what the ls alias was aliased to, you could do alias ls.

3
  • 18
    Or type alias ls to find out what specifically ls is aliased to.
    – poolie
    Commented Feb 7, 2012 at 4:10
  • 2
    @poolie Indeed. I think the question was to see all the aliases, though, which is why i did not elaborate further on the alias command.
    – Thomas Ward
    Commented Feb 7, 2012 at 4:52
  • 3
    while this works for aliases, it doesn't work if you've defined a custom shell function. type however, works in both cases. Commented Sep 24, 2016 at 6:38
77

I really like Ctrl+Alt+E as I learned from this answer. It "expands" the currently typed command line, meaning it performs alias expansion (amongst other things).

What does that mean? It turns any alias, that might be currently written on the command line, into what the alias stands for.

For example, if I type:

$ ls

and then press Ctrl+Alt+E, it is turned into

$ ls --time-style=locale --color=auto
8
  • 1
    have this an equivalent on other distros?
    – sepehr
    Commented Jul 3, 2014 at 13:40
  • 1
    @sepehr Works on Debian, I assume it's a bash feature and should work on any distribution. Commented Jul 3, 2014 at 16:15
  • 5
    you're right, it works on bash but I have zsh and it doesn't work unfortunately.
    – sepehr
    Commented Jul 4, 2014 at 12:46
  • 1
    How to accomplish this on bash OSX?
    – Govind Rai
    Commented Jan 9, 2017 at 4:31
  • 1
    It has one caveat. When an alias includes necessary quotes, they will be removed. So, I get squeue -u davidmh -o %.18i %.9P %.25j %.8u %.8T %.10M %.9l %.6D %R instead of squeue -u davidmh -o "%.18i %.9P %.25j %.8u %.8T %.10M %.9l %.6D %R "
    – Davidmh
    Commented May 4, 2018 at 19:19
23

Strictly speaking correct answer is using BASH_ALIASES array, e.g.:

$ echo ${BASH_ALIASES[ls]}
ls -F --color=auto --show-control-chars
5
  • 3
    I found this useful in a situation where I wanted programmatic access to the actual statement being aliased without the human-useful stuff around it.
    – M. Justin
    Commented Mar 6, 2017 at 20:16
  • this isn't working in zsh
    – ProGrammar
    Commented Apr 18, 2018 at 13:22
  • 1
    @ProGrammar the question was about bash - for zsh you should look questions about zsh
    – noonex
    Commented Apr 18, 2018 at 20:19
  • 1
    Bingo. Exactly what I needed, same as @M.Justin - I want to stack more switches onto the current ls alias without altering what's there. So I'm going alias ls="${BASH_ALIASES[ls]} --time-style=iso" for my case.
    – Rich
    Commented May 29, 2019 at 19:17
  • 1
    Great for 'watch' command which typically doesn't see aliases: watch $(echo "${BASH_ALIASES[ll]}")
    – Rondo
    Commented Feb 18, 2022 at 3:54
6

You could use the which command.

If you set an alias for ls as ls -al and then type which ls, you will see:

ls: aliased to ls -al.

4
  • bash has no which command.
    – geirha
    Commented Sep 11, 2014 at 9:34
  • 2
    Not working for me..
    – chtenb
    Commented Mar 15, 2016 at 13:34
  • 4
    which is a bad way to lookup aliases as explained here: unix.stackexchange.com/questions/10525/… It doesn't even work for me for aliases in bash on Ubuntu. Commented Sep 24, 2016 at 6:36
  • Only solution that worked for me on MacOS/zsh (This is a Bash question on AskUbuntu I know, but AskUbuntu shows up first in Google) Commented Nov 15, 2021 at 16:48
3

At terminal

$ alias | grep ALIAS

Outputs

ALIAS='some_command'

Replace ALIAS with your alias.

1
  • 2
    Redundant. Just run alias <command>
    – Fadi
    Commented Feb 21, 2022 at 0:42

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .