我目前正在处理当前的玩具代码,试图了解asyncio模块。
import asyncio
import os, sys, traceback
from time import time
os.environ['PYTHONASYNCIODEBUG'] = '1'
print(sys.version)
def timed_fib(n):
def fib(n):
return fib(n - 1) + fib(n - 2) if n > 1 else n
a = time()
return fib(n), time() - a
def process_input():
text = sys.stdin.readline()
n = int(text.strip())
print('fib({}) = {}'.format(n, timed_fib(n)))
@asyncio.coroutine
def print_hello():
while True:
print("{} - Hello world!".format(int(time())))
yield from asyncio.sleep(3)
def main():
loop = asyncio.get_event_loop()
loop.add_reader(sys.stdin, process_input)
loop.run_until_complete(print_hello())
if __name__ == '__main__':
main()
然而,试图运行它会产生下面令人难以置信的神秘回溯。如您所见,调试环境变量在上面代码的第五行中设置,但是,回溯仍然非常无益,如下所示:
3.4.3rc1 (v3.4.3rc1:69dd528ca625+, Feb 8 2015, 11:01:19) [MSC v.1600 32 bit (In
tel)]
Traceback (most recent call last):
File "test.py", line 33, in <module>
main()
File "test.py", line 29, in main
loop.run_until_complete(print_hello())
File "C:\Python34\lib\asyncio\base_events.py", line 304, in run_until_complete
self.run_forever()
File "C:\Python34\lib\asyncio\base_events.py", line 276, in run_forever
self._run_once()
File "C:\Python34\lib\asyncio\base_events.py", line 1136, in _run_once
event_list = self._selector.select(timeout)
File "C:\Python34\lib\selectors.py", line 314, in select
r, w, _ = self._select(self._readers, self._writers, [], timeout)
File "C:\Python34\lib\selectors.py", line 305, in _select
r, w, x = select.select(r, w, w, timeout)
OSError: [WinError 10038] An operation was attempted on something that is not a
socket
如何访问更有用的回溯,以及可能出现的问题?如果重要的话,我在Windows 7上。
答案 0 :(得分:6)
select()
仅适用于Windows上的套接字。
要使用文件描述符,您可以尝试使用非基于选择的事件循环code example:
if os.name == 'nt':
loop = asyncio.ProactorEventLoop() # for subprocess' pipes on Windows
asyncio.set_event_loop(loop)
else:
loop = asyncio.get_event_loop()
虽然我怀疑它对sys.stdin
and asyncio
,code example有帮助。