python定时执行任务的三种方式

#!/user/bin/env python
# @Time     :2018/6/7 16:31
# @Author   :PGIDYSQ
#@File      :PerformTaskTimer.py
#定时执行任务命令
#1.定时任务代码
import time,os,sched
# schedule = sched.scheduler(time.time,time.sleep)
# def perform_command(cmd,inc):
#     os.system(cmd)
#     print('task')
# def timming_exe(cmd,inc=60):
#     schedule.enter(inc,0,perform_command,(cmd,inc))
#     schedule.run()
# print('show time after 2 seconds:')
# timming_exe('echo %time%',2)
#2.周期性执行任务
schedule = sched.scheduler(time.time,time.sleep)
def perform_command(cmd,inc):
    #在inc秒后再次运行自己，即周期运行
    schedule.enter(inc, 0, perform_command, (cmd, inc))
    os.system(cmd)
def timming_exe(cmd,inc=60):
    schedule.enter(inc,0,perform_command,(cmd,inc))
    schedule.run()#持续运行，直到计划时间队列变成空为止
print('show time after 2 seconds:')
timming_exe('echo %time%',2)
#3.循环执行命令
# import time,os
# def re_exe(cmd,inc = 60):
#     while True:
#         os.system(cmd)
#         time.sleep(inc)
# re_exe("echo %time%",5)