Bash – How to Use Spaces in a Bash Alias Name

aliasbashunix

I am trying to create an aliases in bash. What I want to do is map ls -la to ls -la | more

In my .bashrc file this is what I attempted:

alias 'ls -la'='ls -la | more'

However it does not work because (I assume) it has spaces in the alias name. Is there a work around for this?

Best Answer

The Bash documentation states "For almost every purpose, shell functions are preferred over aliases." Here is a shell function that replaces ls and causes output to be piped to more if the argument consists of (only) -la.

ls() {
    if [[ $@ == "-la" ]]; then
        command ls -la | more
    else
        command ls "$@"
    fi
}

As a one-liner:

ls() { if [[ $@ == "-la" ]]; then command ls -la | more; else command ls "$@"; fi; }

Automatically pipe output:

ls -la

Related Solutions

.bashrc loading aliases from different file

When you use alias ${alias_line}, the variable is broken up at spaces, ignoring quoting rules.

There are two ways you could fix it:

Remove all quoting from the alias file:
```
ll=ls -lart
psu=ps -fu $USER
```
and put the variable itself in quotes:
```
alias "$alias_line"
```
This works because in bash, ll="ls -lart" and "ll=ls -lart" are exactly equivalent.
Alternatively (this is a better and more common way), have a file with alias commands, and use the . builtin (aka source) to import it.
```
alias pico='nano'
alias psu='ps x'
alias ll='ls -lart'
```
then in your ~/.bashrc:
```
. ~/.aliases
```

The second method is better, since it does not limit you to aliases, but also allows defining functions, which are much more powerful.

Bash – the correct way to alias applications in OS X through bash

Aliases don't work in shell script by design. Otherwise e.g. alias rm='rm -i' will break most shell scripts.

To enable them anyway, set the expand_aliases shell option.

You can create softlinks for these executables in a directory on your $PATH:

ln -s /Applications/Aquamacs.app/Contents/MacOS/Aquamacs /usr/bin/aquamacs

Then just type the new command name, e.g. aquamacs, to run them.

This will allow use of these commands independent of your shell.

Note that for regular OS X applications, a non-blocking way to open them is open -a ProgramName, e.g. open -a Aquamacs. It uses Launch Services' program database (the one e.g. providing the selection of programs for opening a certain file with a non-default editor) and knows where the applications are installed.

Best Answer

Related Solutions

.bashrc loading aliases from different file

Bash – the correct way to alias applications in OS X through bash

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