code: func GetTotalUsedFds() int {
  	pid := os.Getpid()
  
  	cmd := exec.Command("lsof", "-p", strconv.Itoa(pid))
  
  	output, err := cmd.CombinedOutput()
  	if err != nil {
  		return -1
  	}
  
  	outputStr := strings.TrimSpace(string(output))
  
  	fds := strings.Split(outputStr, "\n")
  
  	return len(fds) - 1
  }
docs: // GetTotalUsedFds returns the number of used File Descriptors by
  // executing `lsof -p PID`