from multiprocessing import Pool
import subprocess
import os
import signal
import sys
import time

def mp_logic():
    return ''

def main():
    cnt=1
    process_pool = Pool(processes=1, maxtasksperchild=1)
    while True:
        with subprocess.Popen(['ls', '/tmp'], stdin=subprocess.PIPE,
                              stdout=subprocess.PIPE, stderr=subprocess.PIPE) as p:
            # avoid hanging on big output buffers
            std_out, std_err = p.communicate()

        print('Done process', cnt, flush=True)
        cnt+= 1

        res = process_pool.apply_async(mp_logic, args=())
        time.sleep(0.1)
        x = res.get()

if __name__ == "__main__":
    main()