python 多进程与子进程

#!/usr/bin/env python3
#-*- coding:utf-8 -*-
'''
'''
#多进程,pool
from multiprocessing import Process
from multiprocessing import Pool
import os
import time
import random
def f(name):
    print('hello, %s,pid=%s' % (name, os.getpid()))
if __name__ == '__main__':
    print('Parent process %s ' % os.getpid())
    p=Process(target=f, args=('talen',))
    print('Child process will start.')
    p.start()
    p.join()
    print('Child process end')
def long_time_task(name):
    print('Run task %s (%s)...' % (name,os.getpid()))
    start=time.time()
    time.sleep(random.random() * 3)
    end=time.time()
    print('Task %s runs %0.2f seconds' % (name,(end - start )))
if __name__ == '__main__':
    print('Parent process %s ' % os.getpid())
    pp=Pool(4)
    for i in range(6):
        pp.apply_async(long_time_task,args=(i,))
    print('Child process will start.')
    pp.close()
    pp.join()
    print('Child process end')

#子进程
import subprocess
print('$ nslookup htfchina.blog.chinaunix.net')
r = subprocess.call(['nslookup','htfchina.blog.chinaunix.net'])
print('Exit code :',r)

#输入网址
print('$ nslookup')
subp=subprocess.Popen(['nslookup '], shell=True, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
output, err = subp.communicate(b'set q=mx\n\nexit\n')
print(output.decode('utf-8'))
print('Exit code:',subp.returncode)

/usr/bin/python3 /home/t/PycharmProjects/untitled/mutliprocessing_t.py
Parent process 14001
Child process will start.
hello, talen,pid=14002
Child process end
Parent process 14001
Child process will start.
Run task 0 (14003)...
Run task 1 (14004)...
Run task 2 (14005)...
Run task 3 (14006)...
Task 3 runs 0.02 seconds
Run task 4 (14006)...
Task 0 runs 2.07 seconds
Run task 5 (14003)...
Task 1 runs 2.46 seconds
Task 4 runs 2.58 seconds
Task 2 runs 2.97 seconds
Task 5 runs 2.33 seconds
Child process end
$ nslookup htfchina.blog.chinaunix.net
Server:        10.10.106.201
Address:    10.10.106.201#53

Non-authoritative answer:
Name:    htfchina.blog.chinaunix.net
Address: 61.55.167.140

Exit code : 0
$ nslookup
Server:        10.10.106.201
Address:    10.10.106.201#53

Non-authoritative answer:
www.baidu.com    canonical name = www.a.shifen.com.

Authoritative answers can be found from:
a.shifen.com
    origin = ns1.a.shifen.com
    mail addr = baidu_dns_master.baidu.com
    serial = 1605030003
    refresh = 5
    retry = 5
    expire = 86400
    minimum = 3600


Exit code: 0

Process finished with exit code 0