--- fastri-0.3.1/bin/fastri-server
+++ fastri-0.3.1/bin/fastri-server
@@ -105,12 +105,25 @@ options = {:allowed_hosts => ["127.0.0.1"], :addr => "127.0.0.1",
   :index_file => File.join(home, ".fastri-index"),
   :do_full_text => false, 
   :full_text_dir => File.join(home, ".fastri-fulltext"),
+  :logfile => File.join(home, ".fastri-log"),
 }
 OptionParser.new do |opts|
   opts.version = FastRI::FASTRI_VERSION
   opts.release = FastRI::FASTRI_RELEASE_DATE
   opts.banner = "Usage: fastri-server.rb [options]"
 
+  opts.on("-d", "--daemon", "Run as daemon.") do
+    options[:daemon] = true
+  end
+
+  opts.on("-p", "--pidfile FILE", "Daemon PID file.") do |pidfile|
+    options[:pidfile] = pidfile
+  end
+
+  opts.on("-l", "--logfile FILE", "Daemon log file.") do |logfile|
+    options[:logfile] = logfile
+  end
+
   opts.on("-a", "--allow HOST", "Allow connections from HOST.",
           "(default: 127.0.0.1)") do |host|
     options[:allowed_hosts] << host
@@ -148,6 +161,20 @@ OptionParser.new do |opts|
   end
 end.parse!
 
+# based on http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/87467
+if options[:daemon]
+   exit if Process.fork
+   Process.setsid
+   exit if Process.fork
+   pidfile = File.new(options[:pidfile], "w")
+   pidfile.write(Process.pid.to_s)
+   pidfile.close
+   Dir.chdir("/")
+   STDIN.reopen("/dev/null")
+   STDOUT.reopen(options[:logfile], "a")
+   STDERR.reopen(STDOUT)
+end
+
 if File.exist?(options[:index_file])
   ri_reader = open(options[:index_file], "rb"){|io| Marshal.load io } rescue nil
 end