如何解决此错误：OSError: [Errno 9] Bad file descriptor

Posted 2023-02-18

【中文标题】如何解决此错误：OSError: [Errno 9] Bad file descriptor

【英文标题】：How do I troubleshoot this error: OSError: [Errno 9] Bad file descriptor

【发布时间】：2021-12-05 11:02:22

【问题描述】：

我试图找出问题出在我的客户端和服务器文件之间的位置。客户端收到 TCP 服务器完成的正确计算。但是，TCP 服务器在执行完任务后继续抛出错误。

add_server.py

# This is add_server.py script

import socket 

host = socket.gethostname()
port = 8096

s = socket.socket()
s.bind((host, port))
s.listen(5)

print('Waiting for connection...')
conn, addr = s.accept()

while True:
    data = conn.recv(1024)                          # Receive data in bytes
    print(data)
    decoded_data = data.decode('utf-8')                     # Decode data from bystes to string
    print(data)
    d = decoded_data.split(",")                             # Split the received string using ',' as separator and store in list 'd'
    add_data = int(d[0]) + int(d[1])                # add the content after converting to 'int'

    conn.sendall(str(add_data).encode('utf-8'))     # Stringify results and convert to bytes for transmission (String conversion is a must)
    conn.close()                        # Close connection

add_client.py

# This add_client.py script

import socket

host = socket.gethostname()
port = 8096

s = socket.socket()
s.connect((host, port))

a = input('Enter first number: ')
b = input('Enter second number: ')
c = a + ', ' + b                                    # Generate string from numbers

print('Sending string  to sever for processing...'.format(c))

s.sendall(c.encode('utf-8'))              # Converst string to bytes for transmission

data = s.recv(1024).decode('utf-8')       # Receive server response (addition results) and convert from bystes to string

print(data)                               # Convert 'string' data to 'int'

s.close()                                 # close connection

完整追溯

Traceback (most recent call last):
  File "/home/sharhan/AWS/AWS-PERSONAL-COURSES/linux-networking-and-troubleshooting/python-networking/add_server.py", line 17, in <module>
    data = conn.recv(1024)                          # Receive data in bytes
OSError: [Errno 9] Bad file descriptor

【参考方案1】：

您正在关闭此行中 while 循环内的套接字

while True:
    data = conn.recv(1024) 
    # Rest of the code
    conn.close()  

因此，下次您尝试使用conn.recv 接收数据时，会导致错误。

要解决此问题，只需在接收完所有数据后关闭连接即可。

while True:
    data = conn.recv(1024) 
    # Rest of the code
conn.close() 

【讨论】：

好的。我这样做了，它引发了另一个错误： Traceback（最近一次调用最后一次）：文件“/home/sharhan/AWS/AWS-PERSONAL-COURSES/linux-networking-and-troubleshooting/python-networking/add_server.py”，行22、in add_data = int(d[0]) + int(d[1]) # 转换为'int'后添加内容 ValueError: invalid literal for int() with base 10: ''

最后得到的是空白数据。

请问我该如何解决？我似乎无法获得空白数据的来源

您可以跳过该行并改为print(d) 以查看正在发送的数据

它是空的。相当令人惊讶。但我认为我正在拆分的数据存储在变量“d”中。请问我怎么会错过没有存储在变量“d”中的数据。想不通