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Subprocess.Popen stdin in new console

I want to execute a python subprocess in a new console. Once started, I want the user to be able to answer questions asked by this new process on stdin.
I tried the following code:
p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=cwd, creationflags=subprocess.CREATE_NEW_CONSOLE)
(o, e) = p.communicate()
As soon as the subprocess asks for input on stdin the following error message is displayed:
EOFError: EOF when reading a line
Is it the good way to achieve this ?

As i'm not really interested in the stdout/stderr redirection, i tried this way:
subprocess.Popen(cmd, cwd=cwd, creationflags=subprocess.CREATE_NEW_CONSOLE)
It works fine now. I guess that it's not compatible to redirect standard input/outputs and to create a new console.

Output of subprocess both to PIPE and directly to stdout

I found a number of questions which looks like mine, but which did not produce a solution I can use (closest is: subprocess output to stdout and to PIPE)
The problem: I want to start a process using subprocess which takes a long time. After running the command I need to parse the stdout-output and the stderr-output.
Currently I do it as follows:
p = subprocess.Popen( command_list, stdout=subprocess.PIPE,
stderr=subprocess.PIPE )
out, error_msg = p.communicate()
print out + "\n\n" + error_msg
#next comes code in which I check out and error_msg
But the drawback of this method is that the user does not see the output of the process while it is running. Only at the end the output is printed.
Is there a way that the output is printed while the command is running (as if I gave the command without stdout/stderr=subprocess.PIPE) and still have the output via p.communicate in the end?
Note: I'm currently developing on python 2.5 (old software release which uses this python version).

This snippet has helped me once in a similar situation:
process = subprocess.Popen(cmd, bufsize=1, universal_newlines=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
for line in iter(process.stdout.readline, ''):
print line,
sys.stdout.flush() # please see comments regarding the necessity of this line
process.wait()
errcode = process.returncode

Python2: subprocess.Popen() has another output as it runs direct on console

When i am running a program in the console, i get some text output.
When i am running the same program in Popen(..), with the same parameters, stdout and stderr are empty.
I tried everything i could imagine like shell=False and shell=True, set stdout=subprocess.PIPE, did a os.chdir() to change into the directory of this program, try p.wait() and p.communicate(), set the command as a list and as a string, but nothing works.
example:
p = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE, stdin=subprocess.PIPE)
out, err = p.communicate()
--> out and err are empty strings, but if i ran this command in console i get a real output. Command is with fullpath, so its regardless where the command will be started.
My question is, are there mechanisms for programms to detect they weren't run in a real console? If so, how can i cheat.
Or miss i something?
(Python 2.7.8. x32 in Win7 x64)

from subprocess import Popen, STDOUT, PIPE
p = Popen(command, shell=True, stdout=PIPE, stderr=STDOUT, stdin=PIPE)
while p.poll() is None:
print(p.stdout.read())
p.stdout.close()
p.stdin.close()
Try this and see if it makes any difference. Also make sure command is a string and not a list/touple, shell=True for whatever reason works better or only with strings.
Also note that shell=True will get you hanged because it's insecure etc.
Also skipping .communicate() you'll need to tap off stdout otherwise the buffer will get full and you might hang both yours and the child process.
If this doesn't work, please provide more information. Such as the command used and the expected output (at least first few lines)

Running shell command from Python script

I'm trying to run a shell command from within a python script which needs to do several things
1. The shell command is 'hspice tran.deck >! tran.lis'
2. The script should wait for the shell command to complete before proceeding
3. I need to check the return code from the command and
4. Capture STDOUT if it completed successfully else capture STDERR
I went through the subprocess module and tried out a couple of things but couldn't find a way to do all of the above.
- with subprocess.call() I could check the return code but not capture the output.
- with subprocess.check_output() I could capture the output but not the code.
- with subprocess.Popen() and Popen.communicate(), I could capture STDOUT and STDERR but not the return code.
I'm not sure how to use Popen.wait() or the returncode attribute. I also couldn't get Popen to accept '>!' or '|' as arguments.
Can someone please point me in the right direction? I'm using Python 2.7.1
EDIT: Got things working with the following code
process = subprocess.Popen('ls | tee out.txt', shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
out, err = process.communicate()
if(process.returncode==0):
print out
else:
print err
Also, should I use a process.wait() after the process = line or does it wait by default?

Just use .returncode after .communicate(). Also, tell Popen that what you're trying to run is a shell command, rather than a raw command line:
p = subprocess.Popen('ls | tee out.txt', shell=True, ...)
p.communicate()
print p.returncode

From the docs:
Popen.returncode
The child return code, set by poll() and wait() (and indirectly by communicate()). A None value indicates that the process hasn’t terminated yet.
A negative value -N indicates that the child was terminated by signal N (Unix only).

Here is example how to interact with shell:
>>> process = subprocess.Popen(['/bin/bash'], shell=False, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
>>> process.stdin.write('echo it works!\n')
>>> process.stdout.readline()
'it works!\n'
>>> process.stdin.write('date\n')
>>> process.stdout.readline()
'wto, 13 mar 2012, 17:25:35 CET\n'
>>>

Not able to read subprocess output

I am executing the python command,
proc = subprocess.Popen(cmd,
shell=False,
stdin=subprocess.PIPE,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
after executing command i want to read the stderr and stdout
res = proc.stderr.read()
in res i am expecting any error or ' '
but the reading the stderr is taking infinite time is get hang not reading the values what ever the result it.it goes in infinite time.
Some time back same code is working fine but not idea why its not reading stderr now.
Any Hint, thanks.

Instead of explicitly calling stderr.read(), just do a communicate on the proc.
output, error = proc.communicate()
That way you would get the output and error by communicating with the process.