最近在用subprocess中的Popen做个磁盘监控小程序，但是在使用ps = Popen("df -h", shell=True, stdout=PIPE, stderr=PIPE)之后，再使用output_lines = ps.stdout.readlines()的时候，output_lines总是内容为空，有哪位知道是什么原因么？
btw：我是在windows下设计这个程序的
代码
#!/usr/bin/env python
#coding=utf-8
from subprocess import Popen, PIPE
import re
def disk_space(pattern="2[0-9]%", message="CAPACITY WARNING"):
## take shell command output
ps = Popen("df -h", shell=True, stdout=PIPE, stderr=PIPE)
output_lines = ps.stdout.readlines()
for line in output_lines:
line = line.strip()
if re.search(pattern, line):
print "%s %s" %(message, line)
if __name__ == '__main__':
disk_space
#coding=utf-8
from subprocess import Popen, PIPE
import re
def disk_space(pattern="2[0-9]%", message="CAPACITY WARNING"):
## take shell command output
ps = Popen("df -h", shell=True, stdout=PIPE, stderr=PIPE)
output_lines = ps.stdout.readlines()
for line in output_lines:
line = line.strip()
if re.search(pattern, line):
print "%s %s" %(message, line)
if __name__ == '__main__':
disk_space
来源：https://www.cnblogs.com/bluescorpio/archive/2010/05/04/1727020.html