将文本文件中的 IP 转换为主机名

Question

I'm trying to get hostnames using IPs from text file, but I'm unable to read all IPs from text file and the output shows only one IP.

Below is my COde,

import os
import socket

with open('ips.txt', 'r') as f:
    for line in f.read().strip('\n'):
        ip = line.strip()
        b = socket.getfqdn(ip)
        print b

Thanks.

Answer 1

The problem is in:

for line in f.read().strip('\n'):

this iterates over the whole file content ( f.read() ) without the trailing \\n . Strings are iterables in Python, so essentially you are just iterating over each character of the text file.

Instead, as file objects are iterable, you can do the iteration line by line and get the relevant FQDN:

with open('ips.txt', 'r') as f:
    for line in f:
        ip = line.strip()
        fqdn = socket.getfqdn(ip)
        # print(fqdn)  # Python 3
        print fqdn  # python 2