Python: How do I get the output of Popen?

From:http://www.cnblogs.com/bluescorpio/archive/2010/05/04/1727020.html

A disk monitoring applet was recently used with Popen in subprocess, but after using PS = Popen ("Df-h", Shell=true, Stdout=pipe, stderr=pipe), use Output_lines = Ps.stdout.readlines (), Output_lines always content is empty, who knows what is the reason?

BTW: I designed this program under Windows

Code #!/usr/bin/env python#Coding=utf-8 FromSubprocessImportPopen, PIPEImportRe
DefDisk_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 ()ForLineInchOutput_lines:line=Line.strip ()IfRe.search (pattern, line):print "%s%s" %(message, line) if __name__ = = ' __main__': Disk_space

Python: How do I get the output of Popen?