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Join us and we need to process a series of single digits (0~9). If it is an odd number, we need to loop to print it; if it is an even number, wait for the corresponding time and complete all tasks; if it is 0 It is an error, but there is no need to terminate the task and some processing can be customized.
Define funcFunctionProcessing requirements
Callback processing returns results, only even numbers and 0 are returned; odd numbers will always be executed; thread control is required Pool status , you need to throw an exception for even numbers and 0, and capture exception handling .
threadpool defines thread pool concurrency
# -*- coding: utf-8 -*- from threadpool import makeRequests, ThreadPool import time from multiprocessing import Process
class Finish(SyntaxWarning): pass
class PauseInfo(SyntaxWarning): pass pause_num = 0
Returns False when 0, returns True for other even numbers
def func(para): if para == pause_num: print('start for %d and wait %ds' % (para, 4)) time.sleep(4) print('error bcs ',para) return False if para % 2 == 0: print('start for %d and wait %ds' % (para, para)) time.sleep(para) print('stop for', para) return True while True: print('continue for', para) time.sleep(para)
def callback(request, result): if result: raise Finish else: raise PauseInfo
Finish marks the completion of the task, and induces an exception again to exit the thread pool processing;
def main_thread(paras): pool = ThreadPool(10) requests = makeRequests(callable_=func, args_list=paras, callback=callback) [pool.putRequest(req) for req in requests] while True: try: pool.wait() except Finish as e: raise SystemExit except PauseInfo as e: print('Pause bcs %d but will continue' % pause_num) except Exception as e: print('Unknown error so will quit') raise SystemExit
if name == 'main': while True: s = input('Input number list to test and any other word to quit\n') paras = [] for para in s: if para.isnumeric(): paras.append(int(para)) else: break try: thread_test = Process(target=main_thread, args=(paras,)) thread_test.start() thread_test.join(timeout=20) except TimeoutError as e: print('task timeout') except Exception as e: print('unknow error:',e)
Processing 108, you can see from the print that 1 is processed in a loop, and an error is reported when 0 is processed; 8 is processed and the task End
Input number list to test and any other word to quit
108
continue for 1
start for 0 and wait 4s
start for 8 and wait 8s
continue for 1
continue for 1
continue for 1
error bcs 0
continue for 1
Pause bcs 0 but will continue
continue for 1
continue for 1
continue for 1
continue for 1
stop for 8
Input number list to test and any other word to quit
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