is-process-waiting-for-terminal.py

#!/usr/bin/python

import sys
import time

def is_sleeping(pid):
  with open("/proc/%d/stat" % pid) as stat:
    state = stat.read().strip().split()
    return state[2] == 'S'

def io_stats(pid):
  with open("/proc/%d/io" % pid) as io:
    stats = (stat.split(": ") for stat in io.readlines())
    return {stat[0]: int(stat[1]) for stat in stats}

if __name__ == '__main__':
  pid = int(sys.argv[1])

  while True:
    stats = io_stats(pid)
    last_diff = stats['read_bytes'] - stats['rchar']
    while is_sleeping(pid):
      stats = io_stats(pid)
      cur_diff = stats['read_bytes'] - stats['rchar']
      if cur_diff == last_diff:
        print("Process seems to be blocked reading the terminal!")
      else:
        print("Process is blocked doing something else")
        last_diff = cur_diff

      time.sleep(1)

    print('Process is not sleeping anymore')
    time.sleep(1)