多进程的python实现

import os
import time
#os.fork()负责创建一个新的进程，新的进程也会执行下面的代码。
#而pid的值对于父进程和子进程是不同的。父进程中pid为子进程的#PID，子进程中的pid则为0
pid = os.fork()

# pid greater than 0 represents
# the parent process
if pid > 0 :
    time.sleep(10)
    print("I am parent process:")
    print("Process ID:", os.getpid())
    print("Child's process ID:", pid)

# pid equal to 0 represnts
# the created child process
else :
    time.sleep(5)
    print("nI am child process:")
    print("Process ID:", os.getpid())
    print("Parent's process ID:", os.getppid())