A factory function for safely waiting for (and interacting with) zombie processes.

wait-dont-reap.py

from contextlib import contextmanager
 
@contextmanager
def zombie(process):
    proc_file_name = '/proc/' + str(process.pid) + '/stat'
    while True:
        with open(proc_file_name, 'r') as proc_file:
            if proc_file.readline().split(' ')[2] == 'Z':
                yield process
                break
    # Reap the process
    process.poll()
 
 
 
# Example usage:
import subprocess
 
process = subprocess.Popen( ('sleep', '1'), stdout=subprocess.PIPE)
 
# Listed as `active` in the process table:
subprocess.call( ('ps', '-l') )
 
with zombie(process):
    # Listed as `zombie` in the process table
    subprocess.call( ('ps', '-l') )
    # 'Do stuff with the zombie process'
 
# No longer listed in process table:
subprocess.call( ('ps', '-l') )