gistfile1.txt

    def _syscall_raw(cmd_str)
      outputs = Hash.new
      Open3.popen3(cmd_str) do |stdin,stdout,stderr,wait_thr|
        outputs[:stdout]   = stdout.read
        outputs[:stderr]   = stderr.read
        outputs[:pid] = wait_thr.value.pid
        outputs[:exitstatus] = wait_thr.value.exitstatus
      end
      outputs
    end
    
    def self.syscall(cmd_str,success_retval=nil,dryrun_opts=nil)
      if dryrun
        outputs = dryrun_opts
      else
        outputs = _syscall_raw(cmd_str)
      end
      
      raise_str = <<-STR
Command: \'#{cmd_str}\' failed!
Exitstatus => #{outputs[:wait_thr].value}
Stderr => #{outputs[:stderr]}
STR
  
      if success_retval
        unless outputs[:exitstatus] == success_retval
          raise raise_str
        end
      elsif not outputs[:exitstatus] == 0
        raise raise_str
      end
      outputs
    end