blocking=False 的调度器

Question

Python 调度程序在默认值 blocking=True 下运行良好：

import sched, time
def print_time(a):
    print("From print_time", time.time(), a)
s = sched.scheduler()
s.enter(2, priority=1, action=print_time, argument=(1,))
s.enter(2, priority=2, action=print_time, argument=(2,))
print(time.time())
s.run()  # blocks until the last scheduled task is finished
print('finished')

但我不能让它与 blocking=False 一起工作。

确实有：

s.run(block=False)  
print('finished')

脚本立即停止，显然它不起作用（这是正常行为）。但是：

s.run(block=False)  
time.sleep(10)     # sleeping to make sure the script does not terminate immediately,
print('finished')  # but in real situation, there would be other tasks here

也不行：奇怪的是任务没有执行。

我不太理解文档：

If blocking is false executes the scheduled events due to expire soonest (if any) and then return the deadline of the next scheduled call in the scheduler (if any).

如何在blocking=False模式下使用调度器？

Answer 1

我找到了解决方案：blocking=False 模式允许同时做其他事情并不时轮询新事件。这有效：

import sched, time

def print_time(a):
    print("From print_time", time.time(), a)

s = sched.scheduler()
s.enter(2, priority=1, action=print_time, argument=(1,))
s.enter(2, priority=2, action=print_time, argument=(2,))

for _ in range(50):
   s.run(blocking=False)
   time.sleep(0.1)  # in a real situation, this would be some other tasks

print('finished')

blocking=False 的调度器

Scheduler with blocking=False

python

scheduler

python-multithreading

python-sched