# File lib/lockfile.rb, line 319
    def sweep
      begin
        glob = File.join(@dirname, ".*lck")
        paths = Dir[glob]
        paths.each do |path|
          begin
            basename = File.basename path
            pat = %r/^\s*\.([^_]+)_([^_]+)/o
            if pat.match(basename)
              host, pid = $1, $2
            else
              next
            end
            host.gsub!(%r/^\.+|\.+$/,'')
            quad = host.split %r/\./
            host = quad.first
            pat = %r/^\s*#{ host }/i
            if pat.match(HOSTNAME) and %r/^\s*\d+\s*$/.match(pid)
              unless alive?(pid)
                trace{ "process <#{ pid }> on <#{ host }> is no longer alive" }
                trace{ "sweeping <#{ path }>" }
                FileUtils.rm_f path
              else
                trace{ "process <#{ pid }> on <#{ host }> is still alive" }
                trace{ "ignoring <#{ path }>" }
              end
            else
              trace{ "ignoring <#{ path }> generated by <#{ host }>" }
            end
          rescue
            next
          end
        end
      rescue => e
        warn(errmsg(e))
      end
    end