Less Compiler for Linux

Although using node.js version is recommended, you can install less as ruby gem:

sudo apt-get install rubygems1.8 ruby1.8-dev
sudo gem install rubygems-update
sudo gem update rubygems
sudo gem install less

and than use lessc which is in /var/lib/gems/1.8/bin/lessc, so you may want to create symlink:

sudo ln -s /var/lib/gems/1.8/bin/lessc /usr/bin/

or add ruby gems dir to PATH variable:

export PATH=/var/lib/gems/1.8/bin:$PATH

EDIT:

Using lessc as described here:

Command-line usage

Less comes with a binary, which lets you invoke the compiler from the
command-line, as such:
$ lessc styles.less
This will output the compiled CSS to stdout, you
may then redirect it to a file of your choice:
$ lessc styles.less > styles.css
To output minified CSS, simply pass
the -x option.

linux less compiler watch for @import updates

You can use Grunt and especially grunt-contib-watch, see Grunt, Less, and File Watching for an example.

Notice that also the client side less.js compiler has got a watch function, see http://lesscss.org/usage/#using-less-in-the-browser-watch-mode.

How to automatically compile LESS into CSS on the server?

I have made a script and I publish the details:

Easy to use for designers
Executes LESS compiler immediately after file is saved, without consuming server resources
Any editor capable of remote editing will work with this solution - Code, Sublime Text, Textmate

First, you need to install "npm" on the server by typing this into the console:

sudo apt-get install npm inotify-tools
sudo npm install -g less
sudo nano /usr/local/bin/lesscwatch

Paste the following into the file:

#!/bin/bash
# Detect changes in .less file and automatically compile into .css
[ "$2" ] || { echo "Specify both .less and .css files"; exit 1; }
inotifywait . -m -e close_write | while read x op f; do.
    if [ "$f" == "$1" ]; then.
        lessc $f > $2 && echo "`date`: COMPILED";.
    fi
done

Save, exit, then execute:

sudo chmod +x /usr/local/bin/lesscwatch

You are all done. Next time you need to work with your LESS files, you will need to open terminal (Coda has a built-in), go to the folder of your file (using cd) and execute this:

lesscwatch main.less main.css

It will output information about successful compilations or errors. Enjoy.

Less CSS compiler on Ubuntu: How to watch dependencies and compile on save

If your less files are stored in subfolders of less/, you can watch for changes with inotifywait:

sudo apt-get install inotify-tools

Then create a autocompile.sh file:

#! /bin/bash
while inotifywait -r less/*
do
  lessc less/main.less > css/main.css # your compile command
done

Don't forget to give it execution rights:

chmod u+x autocompile.sh

And run it:

./autocompile.sh

Your compile command will be run every time a file in less/ will be modified.

LESS CSS on Windows

I think I found the problem. In my first installation I installed to C:\Program Files\Ruby
so I uninstalled and tried the default 'C:\Ruby' install path. Seems to fix the problem and it now works correctly. Thanks.

Current state of LESS CSS on Linux

lessphp is a LESS compiler written entirely in PHP, making it very easy to run on the server side if you're already using PHP. It was finally just added to Packagist yesterday! You can install it on a project to project basis using composer. Here is an example composer.json file for declaring it as a dependency to your own project:

{
    "require": {
        "leafo/lessphp": "dev-master"
    }
}

Less Compiler for Linux