Python腳本中的ping請求失敗

Question

我有一個python腳本，想ping幾個（相當於幾個！）主機。我已經將它設置爲讀取hosts.txt文件的內容作爲主機在腳本中進行ping操作。奇怪的是，我recieving下面的錯誤，在最初的幾個地址（無論它們是什麼）：

Ping request could not find host 66.211.181.182. Please check the name and try again. 

我已經包含如上圖所示，在兩次（在文件中）的地址，它會嘗試平。任何想法，我做錯了 - 我是一個蟒蛇新手，所以要溫柔。

---

這裏是我的腳本：

import subprocess 

hosts_file = open("hosts.txt","r") 
lines = hosts_file.readlines() 

for line in lines: 
    ping = subprocess.Popen(
     ["ping", "-n", "1",line], 
     stdout = subprocess.PIPE, 
     stderr = subprocess.PIPE 
    ) 
    out, error = ping.communicate() 
    print out 
    print error 
hosts_file.close() 

這裏是我的HOSTS.TXT文件：

66.211.181.182 
178.236.5.39 
173.194.67.94 
66.211.181.182 

這裏是從上面的測試結果：

Ping request could not find host 66.211.181.182 
. Please check the name and try again. 


Ping request could not find host 178.236.5.39 
. Please check the name and try again. 


Ping request could not find host 173.194.67.94 
. Please check the name and try again. 



Pinging 66.211.181.182 with 32 bytes of data: 
Request timed out. 

Ping statistics for 66.211.181.182: 
    Packets: Sent = 1, Received = 0, Lost = 1 (100% loss) 

Answer 1

看起來像line變量在結尾處包含換行符（文件的最後一行除外）。從Python tutorial：

f.readline()從文件讀取一行;一個換行符（\n）留在字符串的末尾，並且只在文件的最後一行中省略，如果該文件不以換行符結束。

你需要調用Popen之前剝離\n：How can I remove (chomp) a newline in Python?

Answer 2

幾點意見：

1. 使用readlines方法（）強烈不推薦，因爲它會在整個文件加載到內存中。
2. 我建議使用發生器爲了在每一行執行rstrip然後ping服務器。
3. 無需file.close使用 - 你可以用它做你

您的代碼語句中使用應該是這樣的：

import subprocess 
def PingHostName(hostname): 
    ping=subprocess.Popen(["ping","-n","1",hostname],stdout=subprocess.PIPE 
        ,stderr=subprocess.PIPE) 
    out,err=ping.communicate(); 
    print out 
    if err is not None: print err 

with open('C:\\myfile.txt') as f: 
    striped_lines=(line.rstrip() for line in f) 
    for x in striped_lines: PingHostName(x)