使用python從操作系統讀取用戶數量

Question

我正在編寫一個將基於登錄到我的實例的用戶數退出的nagios插件。

import argparse 
import subprocess 
import os 
import commands 
import sys 

if __name__ == '__main__': 
     parser = argparse.ArgumentParser(description='checks number of logged in users') 
     parser.add_argument('-c','--critical', help='enter the value for critical limit', nargs='?', const=10) 
     parser.add_argument('-w','--warning', help='enter the value for warning limit', nargs='?', const=5) 
     args = parser.parse_args() 
     x= commands.getstatusoutput("users | tr ' ' '\n' | sort -u | wc -l") 
     a= os.popen("users | tr ' ' '\n' | sort -u | wc -l").read() 
     print type(a) 
     print "value of critical is %s" % (args.critical) 
     print a 
     (co, res) = x 
     print "result from command is %s" % (res) 
     print type(res) 
     if a >= args.critical: 
       print "we are critical" 
       sys.exit(2) 
     elif a <= args.warning: 
       print " we are ok" 
       sys.exit(0) 
     elif (a >= args.warning and a < args.critical): 
       print "we are warning" 
       sys.exit(1) 
     else: 
       print "Unkown" 
       sys.exit(3) 

但是問題是我的if語句的結果我從commands.getstatusoutput獲取或os.popen是字符串。我如何從shell命令中獲得實際的用戶數量。

python test.py -c 
<type 'str'> 
value of critical is 10 
1 

result from command is 1 
<type 'str'> 
we are critical 

Answer 1

將字符串轉換爲整數使用函數int（）。例如，res_integer = int(res)