人工智能之编程进阶 Python高级：第八章 网络并发类模块

import socket

server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.bind(('localhost', 8888))
server.listen(5)  # 最多排队 5 个连接

print("服务器启动，等待连接...")

while True:
    client, addr = server.accept()
    print(f"客户端 {addr} 已连接")
    
    data = client.recv(1024).decode('utf-8')
    print("收到:", data)
    
    client.send(b"Hello from server!")
    client.close()

import socket

client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
client.connect(('localhost', 8888))
client.send(b"Hello server!")
response = client.recv(1024)
print("服务器回复:", response.decode())
client.close()

# 服务端
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind(('localhost', 9999))
data, addr = sock.recvfrom(1024)
sock.sendto(b"Got it!", addr)

# 客户端
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.sendto(b"Hi UDP!", ('localhost', 9999))
data, _ = sock.recvfrom(1024)

import threading
import time

def worker(name):
    print(f"线程 {name} 开始")
    time.sleep(2)
    print(f"线程 {name} 结束")

# 创建并启动线程
t1 = threading.Thread(target=worker, args=("A",))
t2 = threading.Thread(target=worker, args=("B",))

t1.start()
t2.start()

t1.join()  # 等待线程结束
t2.join()
print("所有线程完成")

lock = threading.Lock()
counter = 0

def increment():
    global counter
    for _ in range(100000):
        with lock:  # 或 lock.acquire() / lock.release()
            counter += 1

t1 = threading.Thread(target=increment)
t2 = threading.Thread(target=increment)
t1.start(); t2.start()
t1.join(); t2.join()
print(counter)  # 应为 200000

import asyncio

async def say_hello(delay, name):
    await asyncio.sleep(delay)  # 异步等待（不阻塞其他任务）
    print(f"Hello {name}!")

async def main():
    # 并发运行多个协程
    await asyncio.gather(
        say_hello(1, "Alice"),
        say_hello(2, "Bob"),
        say_hello(0.5, "Charlie")
    )

# 启动事件循环
asyncio.run(main())

import aiohttp
import asyncio

async def fetch(url):
    async with aiohttp.ClientSession() as session:
        async with session.get(url) as response:
            return await response.text()

async def main():
    urls = ["https://httpbin.org/delay/1"] * 5
    tasks = [fetch(url) for url in urls]
    results = await asyncio.gather(*tasks)
    print("全部完成！")

asyncio.run(main())

import subprocess

# 运行命令并获取输出
result = subprocess.run(["ls", "-l"], capture_output=True, text=True)
print(result.stdout)

proc = subprocess.Popen(
    ["ping", "baidu.com"],
    stdout=subprocess.PIPE,
    stderr=subprocess.PIPE,
    text=True
)

# 读取输出（非阻塞需配合 select 或线程）
try:
    stdout, stderr = proc.communicate(timeout=10)
    print(stdout)
except subprocess.TimeoutExpired:
    proc.kill()
    print("超时，已终止")

from multiprocessing import Pool
import os

def cpu_task(n):
    return sum(i*i for i in range(n))  # 纯 CPU 计算

if __name__ == '__main__':
    with Pool() as pool:  # 自动使用 CPU 核心数
        results = pool.map(cpu_task, [1000000] * 4)
    print(results)