OpenSSH, that ships with Cygwin has a nice utility called ssh-agent. This program is a daemon that will hold on to your keys so that hosts you are authorized to log on to will not continually ask for your password. This is especially useful when working with CVS repositories over SSH. When you run ssh-agent, it spits out text that should be evaluated to set two environment variables that you will need in order to run ssh-add, to actually add your keys to it. That output looks like this:

  
SSH_AUTH_SOCK=/tmp/ssh-mjKjm512/agent.512; 
export SSH_AUTH_SOCK;  
SSH_AGENT_PID=1600; 
export SSH_AGENT_PID;  
echo Agent pid 1600;

On a Unix system, it’s easy to capture the output of ssh-agent and evaluate it, but under the ‘command shell’ that ships with Windows systems, which is so pathetically crippled that my old Commodore 64’s BASIC-based shell is looking pretty good, you can’t do that.

So what are those poor saps, myself included, who are using Windows systems to do? Ruby to the rescue. I wrote a simple script that executes ssh-agent, capturing the output, massaging it a little, and then creating a batch file that I can run to set the necessary variables. Simply redirecting the output to a batch file won’t work because there are some Unix-isms, such as exporting the variables, that don’t work on Windows. So, here’s the script:

#!ruby   
lines = %x{ssh-agent}   
File.open("c:/tmp/sde.bat", "w") do |file|   
  lines.each do |line|   
    chunks = line.chomp.split ';'   
    if chunks[0] =~ /^SSH/  
      file.puts "SET #{chunks[0]}"  
    end  
  end  
end  

You can see that the script sends the captured and massaged output to a batch file called “sde.bat” located in C:/tmp. You can change both of these to suit your preference. Once the script runs, I simply execute the generated batch file and then run ssh-add. The nice thing about the generated batch file is that it lingers until the next time I run the Ruby script. Thus as I open new console Windows I can re-run it to get the environment variables set properly in each one.

After reading several threads about the text scrmabler and various implementations, I revised my Ruby version and it’s now 21 lines shorter and much more Ruby-like. It makes far less of an attempt to deal with punctuation, but I think that’s OK. This is just a lark, after all.

  1  class Mixer  2      private  3      def randomize(str)  4          return str if str.length < 4  5  6          str =~ /B.*B/  7          first = $`  8          last = $'  9          first + ($&.split(//).sort_by {rand}.join) + last 10      end 11 12      public 13      def mix_file(filename) 14          lines = IO.readlines(filename) 15 16          mix_lines(lines) 17      end 18 19      def mix_string(str) 20          mix_lines(str.split).join(" ") 21      end 22 23      def mix_lines(lines) 24          lines.collect! do |line| 25              words = Array.new 26 27              line.split(/W/).each do |word| 28                  words << randomize(word) 29              end 30 31              words.join(" ") 32          end 33      end 34  end 

“Popular demand,” yeah… right… That’s the ticket. Anyway, I saw this blog entry by Jamie this morning which caused me to write a Ruby program to mix up the letters of words, leaving the first and last letter as they were. I started out with a simple script, then I added better punctuation support, then I converted it to a class, then I wrote unit tests to run it. Anyway, somebody wanted to see it, so here it is. Is it great code? Probably not. Do I care? Not really.

  1  class Mixer  2      private  3      def randomize(str)  4          if str.length < 4  5              return str  6          end  7  8          letters = str.split(//)  9 10          first = letters[0] 11          mid = letters[1..(letters.length - 2)] 12          last = letters[letters.length - 1] 13 14          new_letters = "" 15 16          while mid && mid.length > 0 17              len = mid.length 18              r = rand(len) 19              new_letters << mid.delete_at(r) 20          end 21 22          first + new_letters + last 23      end 24 25      public 26      def mix_file(filename) 27          lines = IO.readlines(filename) 28 29          mix_lines(lines) 30      end 31 32      def mix_string(str) 33          new_str = "" 34 35          mix_lines(str.split).each do |line| 36              new_str << line 37          end 38 39          new_str 40      end 41 42      def mix_lines(lines) 43          lines.collect! do |line| 44              new_line = "" 45 46              line.split(/s+|,|.|!|(|)|"|'/).each do |word| 47                  new_line << randomize(word) << " " 48              end 49 50              new_line 51          end 52 53          lines 54      end 55  end 

And the unit tests, which don’t actually test anything.

  1  require 'test/unit'  2  require 'mix'  3  4  class MixTest < Test::Unit::TestCase  5      def setup()  6          @mixer = Mixer.new  7      end  8  9      def test_word() 10          x = @mixer.mix_string("testing") 11          puts x 12          assert_not_equal("testing", x, "String not randomized") 13      end 14 15      def test_string() 16          x = @mixer.mix_string("this is a humongous test, dangit") 17          puts x 18      end 19 20      def test_file() 21          article = @mixer.mix_file("testfile.txt") 22          #puts article 23      end 24  end 

I’m sure someone will find this useful… Again, “yeah, right.” Ah well, it was a mildly amusing diversion…