Question

我需要在python的socket recv方法上设置超时。怎么做？

Answer 1

典型的方法是使用select()等待数据可用或直到超时发生。仅在数据实际可用时调用recv()。为了安全起见，我们还将套接字设置为非阻塞模式，以确保recv()永远不会无限期地阻塞。 select()也可以用于一次等待多个套接字。

import select

mysocket.setblocking(0)

ready = select.select([mysocket], [], [], timeout_in_seconds)
if ready[0]:
    data = mysocket.recv(4096)

如果你有很多打开的文件描述符，poll()是select()的一种更有效的替代方法。

另一种选择是使用socket.settimeout()为套接字上的所有操作设置超时，但我看到你在另一个答案中明确拒绝了该解决方案。

Answer 2

有socket.settimeout()

Answer 3

如前所述，select.select()和socket.settimeout()都可以使用。

请注意，您可能需要根据需要致电settimeout两次，例如

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.bind(("",0))
sock.listen(1)
# accept can throw socket.timeout
sock.settimeout(5.0)
conn, addr = sock.accept()

# recv can throw socket.timeout
conn.settimeout(5.0)
conn.recv(1024)

Answer 4

您可以在收到响应之前设置超时，并在收到响应后将其设置回无：

sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

sock.settimeout(5.0)
data = sock.recv(1024)
sock.settimeout(None)

Answer 5

您正在寻找的超时是连接套接字的超时而不是主套接字，如果您实现服务器端。换句话说，连接套接字对象有另一个超时，它是socket.accept()方法的输出。因此：

sock.listen(1)
connection, client_address = sock.accept()
connection.settimeout(5)    # This is the one that affects recv() method.
connection.gettimeout()     # This should result 5
sock.gettimeout()           # This outputs None when not set previously, if I remember correctly.

如果您实施客户端，那将很简单。

sock.connect(server_address)
sock.settimeout(3)

Answer 6

如先前的答复所述，您可以使用类似.settimeout()的内容例如：

import socket

s = socket.socket()

s.settimeout(1) # Sets the socket to timeout after 1 second of no activity

host, port = "somehost", 4444
s.connect((host, port))

s.send("Hello World!\r\n")

try:
    rec = s.recv(100) # try to receive 100 bytes
except socket.timeout: # fail after 1 second of no activity
    print("Didn't receive data! [Timeout]")
finally:
    s.close()

我希望这会有所帮助！

Answer 7

您可以使用socket.settimeout()来接受表示秒数的整数参数。例如，socket.settimeout(1)会将超时设置为1秒

Answer 8

#! /usr/bin/python3.6

# -*- coding: utf-8 -*-
import socket
import time
s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
s.settimeout(5)
PORT = 10801

s.bind(('', PORT))
print('Listening for broadcast at ', s.getsockname())
BUFFER_SIZE = 4096
while True:
    try:
        data, address = s.recvfrom(BUFFER_SIZE)
    except socket.timeout:
        print("Didn't receive data! [Timeout 5s]")
        continue

Answer 9

尝试使用底层C。

timeval = struct.pack('ll', 2, 100)
s.setsockopt(socket.SOL_SOCKET, socket.SO_RCVTIMEO, timeval)

Answer 10

大声喊叫：https://boltons.readthedocs.io/en/latest/socketutils.html

它提供了一个缓冲套接字，它提供了许多非常有用的功能，例如：

.recv_until()    #recv until occurrence of bytes
.recv_closed()   #recv until close
.peek()          #peek at buffer but don't pop values
.settimeout()    #configure timeout (including recv timeout)

Answer 11

最热门的答案有些混乱，因此I've wrote a small gist带有一些示例，可以使您更好地理解。

选项1-socket.settimeout()

如果sock.recv()等待的时间超过了定义的超时时间，则会引发异常。

import socket

sock = socket.create_connection(('neverssl.com', 80))
timeout_seconds = 2
sock.settimeout(timeout_seconds)
sock.send(b'GET / HTTP/1.1\r\nHost: neverssl.com\r\n\r\n')
data = sock.recv(4096)
data = sock.recv(4096) # <- will raise a socket.timeout exception here

选项2-select.select()

等待直到发送数据直到达到超时为止。我已对Daniel's answer进行了调整，因此它将引发异常

import select
import socket

def recv_timeout(sock, bytes_to_read, timeout_seconds):
    sock.setblocking(0)
    ready = select.select([sock], [], [], timeout_seconds)
    if ready[0]:
        return sock.recv(bytes_to_read)

    raise socket.timeout()

sock = socket.create_connection(('neverssl.com', 80))
timeout_seconds = 2
sock.send(b'GET / HTTP/1.1\r\nHost: neverssl.com\r\n\r\n')
data = recv_timeout(sock, 4096, timeout_seconds)
data = recv_timeout(sock, 4096, timeout_seconds) # <- will raise a socket.timeout exception here

如何在python的socket recv方法上设置超时？

11 个答案: