Python Threading Library's Frequently Asked Questions Answers -Treatment of Multi -threaded abnormalities and synchronization issues
Python's `Threading` library is a commonly used tool for processing multi -threaded programming.It provides a simple and powerful way to create and manage multi -threading, but it may encounter some common problems during use.This article will answer how to deal with multi -threaded abnormalities and synchronization questions, and provide a complete programming code and related configuration when needed.
1. How to deal with multi -threaded abnormalities?
In multi -threaded programming, abnormal treatment is an important task.Each thread has its own abnormal processing mechanism.The following are several common methods to deal with multi -threaded abnormalities:
-Ad using `Try` and` Except`: You can use the `Try` and` Except` blocks in the main functions of the thread to capture abnormalities and deal with them.Then you can choose to terminate the thread or take other appropriate measures.
python
import threading
def my_thread_func():
try:
# The main task of thread
...
except Exception as e:
# Treatment abnormal
...
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
-Ad the use of thread abnormal processors: You can create a custom thread anomaly processor to handle the abnormalities in the thread.It will automatically call it automatically when unsatisfactory abnormalities appear.
python
import threading
def my_thread_exception_handler(exctype, value, traceback):
# Treatment abnormal
...
# Set thread abnormal processor
threading.excepthook = my_thread_exception_handler
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
-Af use of `Thread.Join ()` method: This method can ensure that the main threads will always wait before the end of the thread.In this way, if the thread is abnormal, the main thread will be notified and can be processed.
python
import threading
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
# 束
my_thread.join()
# Here to deal with abnormalities
2. How to solve the problem of multi -threaded synchronization?
In multi -threaded environments, if multiple threads access and modify sharing resources at the same time, synchronous problems will occur.The following are several commonly used technologies to solve the problem of multi -thread synchronization:
-Ad the lock: You can use the `Threading.Lock` to create a lock object, and the lock and release lock when needed.During the lock, other threads will be blocked until the lock is released.
python
import threading
# Create a lock object
my_lock = threading.Lock()
def my_thread_func():
# Need synchronous code
...
# # Lock
my_lock.acquire()
try:
# Access and modify shared resources
...
finally:
# Release lock
my_lock.release()
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
-Mutex: Mutex is a special lock. It allows a thread to exclusive shared resources. Other threads must wait.The `Threading` library provides` Threading.rlock` as a realization of mutual amounts.
python
import threading
# 斥
my_mutex = threading.RLock()
def my_thread_func():
# Need synchronous code
...
# # Lock
my_mutex.acquire()
try:
# Access and modify shared resources
...
finally:
# Release lock
my_mutex.release()
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
-Catter variables: Condition variables allow threads to wait under specific conditions.The `Threading` library provides a` Threading.Condition` class to achieve condition variables.
python
import threading
# Create a condition variable object
my_condition = threading.Condition()
def my_thread_func():
# Need synchronous code
...
with my_condition:
# 检 检
while not condition_is_met():
# 足 satisfied
my_condition.wait()
# 执 执
# 条 Other thread conditions have been met
my_condition.notify_all()
#
my_thread = threading.Thread(target=my_thread_func)
my_thread.start()
This article introduces a common method of how to deal with multi -threaded abnormalities and synchronization problems, and provides a complete programming code and related configuration using the `Threading` Library.By correcting abnormalities and synchronization problems, reliable and stable multi -threaded applications can be better written.