psutil: list process based on ppid

process_info.py

# Rationale: find all subprocesses of a certain command and do something similar to os.killpg
# We need the process ids to wait and be more aggressive if they don't terminate in due time.

import psutil

def print_info(process):
    with process.oneshot():
        print 'pid={0}, ppid={1}, cmd={2}'.format(process.pid, process.ppid(), str(process.cmdline()))

def process_info(pid):
    pids = set()
    try:
        parent = psutil.Process(pid)
        pids.add(parent.pid)
        print_info(parent)
    except psutil.NoSuchProcess:
        return pids
    for child in parent.children(recursive=True):
        pids.add(child.pid)
        print_info(child)
    return pids