Dialog with a process via subprocess.Popen blocks forever

Hi,

I am trying to communicate with a subprocess via the subprocess
module. Consider the following example:

from subprocess import Popen, PIPE
Popen("""python -c 'input("hey")'""", shell=True)
<subprocess.Popen object at 0x729f0>
hey

Here hey is immediately print to stdout of my interpreter, I did not
type in the "hey". But I want to read from the output into a string,
so I do

x = Popen("""python -c 'input("hey\n")'""", shell=True, stdout=PIPE, bufsize=2**10)
x.stdout.read(1)
# blocks forever

Is it possible to read to and write to the std streams of a
subprocess? What am I doing wrong?

Regards,
-Justin

.

Relevant Pages

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