subprocess.Popen objects: how to ensure that stdin is closed

Harishankar v.harishankar at
Fri Apr 2 06:17:55 EDT 2010

I am writing a small app which requires input using stdin to the 

I use the following technique:

proc = subprocess.Popen (cmdargs, stdin=subprocess.PIPE)

proc.stdin.write ("Something")
proc.stdin.flush ()
proc.stdin.write ("something else")
proc.stdin.flush ()

and so on. I cannot use communicate() because it waits till program 
termination and so obviously can be used once only.

The problem is that I want to close the process and it's not responding 
either to proc.stdin.close() or even proc.terminate() which is in 
Python 2.6 (not in 2.5.x)

So I am left with a mangled terminal.

Is subprocess behaving funny or am I doing something wrong? I am not even 
sure if the proc.stdin.close () is respected because even without it, I 
am getting the same mangled state. I just want to control the commands 
using stdin.write and then close the process when done.

Harishankar (

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