# File shell/system-command.rb, line 17
    def initialize(sh, command, *opts)
      if t = opts.find{|opt| !opt.kind_of?(String) && opt.class}
        Shell.Fail Error::TypeError, t.class, "String"
      end
      super(sh)
      @command = command
      @opts = opts
      
      @input_queue = Queue.new
      @pid = nil

      sh.process_controller.add_schedule(self)
    end

# File shell/system-command.rb, line 38
    def active?
      @shell.process_controller.active_job?(self)
    end

# File shell/system-command.rb, line 144
    def each(rs = nil)
      while (l = @input_queue.pop) != :EOF
        yield l
      end
    end

# File shell/system-command.rb, line 60
    def flush
      @pipe_out.flush if @pipe_out and !@pipe_out.closed?
    end

# File shell/system-command.rb, line 42
    def input=(inp)
      super
      if active?
        start_export
      end
    end

# File shell/system-command.rb, line 75
    def kill(sig)
      if @pid
        Process.kill(sig, @pid)
      end
    end

# File shell/system-command.rb, line 156
    def notify(*opts, &block)
      Thread.exclusive do
        @shell.notify(*opts) {|mes|
          yield mes if iterator?

          mes.gsub!("%id", "#{@command}:##{@pid}")
          mes.gsub!("%name", "#{@command}")
          mes.gsub!("%pid", "#{@pid}")
        }
      end
    end

# File shell/system-command.rb, line 49
    def start
      @pid, @pipe_in, @pipe_out = @shell.process_controller.sfork(self) {
        Dir.chdir @shell.pwd
        exec(@command, *@opts)
      }
      if @input
        start_export
      end
      start_import
    end

# File shell/system-command.rb, line 116
    def start_export
      notify "job(%id) start exp-pipe.", @shell.debug?
      _eop = true
      th = Thread.start{
        Thread.critical = true
        begin
          Thread.critical = false
          @input.each{|l| @pipe_out.print l}
          _eop = false
        rescue Errno::EPIPE
          _eop = false
        ensure
          if _eop
            notify("shell: warn: Process finishing...",
                   "wait for Job(%id) to finish pipe exporting.",
                   "You can use Shell#transact or Shell#check_point for more safe execution.")
#           Tracer.on
            redo
          end
          Thread.exclusive do
            notify "job(%id) close exp-pipe.", @shell.debug?
            @pipe_out.close
          end
        end
      }
    end

# File shell/system-command.rb, line 82
    def start_import
#      Thread.critical = true
      notify "Job(%id) start imp-pipe.", @shell.debug?
      rs = @shell.record_separator unless rs
      _eop = true
#      Thread.critical = false
      th = Thread.start {
        Thread.critical = true
        begin
          Thread.critical = false
          while l = @pipe_in.gets
            @input_queue.push l
          end
          _eop = false
        rescue Errno::EPIPE
          _eop = false
        ensure
          if _eop
            notify("warn: Process finishing...",
                   "wait for Job[%id] to finish pipe importing.",
                   "You can use Shell#transact or Shell#check_point for more safe execution.")
#           Tracer.on
            Thread.current.run
            redo
          end
          Thread.exclusive do
            notify "job(%id}) close imp-pipe.", @shell.debug?
            @input_queue.push :EOF
            @pipe_in.close
          end
        end
      }
    end

# File shell/system-command.rb, line 64
    def terminate
      begin
        @pipe_in.close
      rescue IOError
      end
      begin
        @pipe_out.close
      rescue IOError
      end
    end

# File shell/system-command.rb, line 34
    def wait?
      @shell.process_controller.waiting_job?(self)
    end