class_docstr: Polls smi in a forked child process, saves measurements to instance vars
code: def __waitForInput(fd):
      # assume non-blocking fd
      while True:
          if not fd.closed:
              line = fd.readline()
              if line:
                  return line
          else:
              break
      return None
  
file_path: cugraph/python/utils/gpu_metric_poller.py
imports: import os
  import sys
  import threading
  from pynvml import smi
label_desc: Use image node_id 2 for calling the GPUMetricPoller obj's underlying member method code with example usage: obj.__waitForInput(fd) and returns: None, line