Ruby Command Line Scripting

Why Ruby?

It’s syntax is easy to learn and you end up with easy to read code.

The Solution 
 how to look through a directory for files
Here is the code I used to rename any files with the name ._something (like ._Apple) into something.icns:

puts "hello world\n"

  Dir["._*"].each do |file|
    unless file =~ /._(\w|\s)+.rtf/ || file =~ /._(\w|\s)+.webloc/
      puts "#{file} renamed"
      newfile = String.new(file.delete "._")
      newfile << ".icns"
      File.rename(file, newfile)
      puts "Renamed to #{file}\n"
    end
  end

  puts "\n\n"

unless file =~ /._(\w|\s)+.rtf/ || file =~ /._(\w|\s)+.webloc/
This line says if a string matches ._(one or more letters or spaces).rtf or ._(one or more letters or spaces).webloc it will ignore it. The unless means unless this is true do the following, pretty straightforward. The + means one or more of the things inside the parenthesis. The =~ is used to match something to a regular expression. And finally the || means ‘or’ much like in many other computer language.

In order to run this script, I saved it as rename.rb file and then just typed ruby rename.rb on the command line in the directory I wanted it to perform the task.

ruby regexp tutorial