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Struggling with Python's subprocess.Popen running a Perl script

I have a Perl script that I need to run with Python, and I've been trying to use subprocess to do it, unsuccessfully. I'm able to get the command to run just fine on the command line, but subprocess isn't able to get it to work.
If I have a Perl script like this:
#!/usr/bin/perl
use strict;
use warnings;
my $name = shift;
print "Hello $name!\n";
I am able to successfully run the command on the command line like so
C:\current\path> perl test.pl world
>>>Hello world!
But when I try and invoke the same command with subprocess, I get this error
cmd = 'perl test.pl world'
pipe = subprocess.Popen(cmd,shell=True,stdout=subprocess.PIPE)
>>>"'perl' is not recognized as an internal or external command, operable program or batch file."
I've tried different combinations of creating cmd as a list
cmd = ['perl','test.pl','world']
and of giving subprocess the absolute path to Perl
cmd = ['C:\path\to\perl.exe','test.pl','world']
but nothing gets it to work. I'm able to get subprocess to play well without Perl
pipe = subprocess.Popen('dir',shell=True,stdout=subprocess.PIPE)
pipe.stdout.read()
>>>Volume in drive C is Windows7_OS....
I'm absolutely sure that Perl is in my PATH, because like I said I can invoke the command just fine in the command line. I've looked around at different posts that suggested to check os.environ["COMSPEC"], adding Perl to the subprocess env, and nothing has worked.
EDIT: I also can't get the command to work with any other subprocess methods: check_output() returns an empty byte string, and call() returns 1.
Any sort of fix or alternative solution would be immensely appreciated. I'm running Python 3.4 on Windows 7 64bit. I've tried 32- and 64-bit Python as well, to no avail.
UPDATE:
I've been able to get this to work on Mac, but with one difference: I can't have shell=True. Other than that, any subprocess function I want will work, including Popen, check_output, and call.
So I guess this is a Windows problem more than anything. I've tried not setting shell=True on my Windows machine, but I always get this error:
WindowsError: [Error 193] %1 is not a valid Win32 application
UPDATE 2:
I've also tried creating a .bat file that runs the command, but I get the same error as well I try to just call Perl.
pipe = subprocess.Popen('test.bat',shell=True,stdout=subprocess.PIPE)
>>>"'test.bat' is not recognized as an internal or external command, operable program or batch file."
Where test.bat has only one line:
echo Hello, World

you could try using os.system('command') instead. Apparently its not well regarded for some reason, or at least not as well regarded as subprocess though. Alternately, you could try some of the other subprocess methods, such as call, check_call, or check_output. I've had a similar problem with Popen in the past and switching to one of these methods helped.

I got the same error while trying to run a perl script from Python.
I managed to get it work by adding the full path of the perl.exe (with an extra escape character, as '\') to the command I was trying to run as below:
pipe = subprocess.Popen('C:\\Perl64\\bin\\perl myscrip.pl',shell=True,stdout=subprocess.PIPE)
pipe.stdout.read()

This works fine for me. I know it's been a while and things may have just fixed themselves.
I'm using activestate perl 5.8.9
and python 3.9.5 on Windows 10.
from subprocess import Popen, PIPE
proc = Popen(['perl', 'test.pl', 'world'], stdout=PIPE, stderr=PIPE)
stdout, stderr = proc.communicate()
if proc.returncode == 0:
print(stdout.decode())
else:
print(stderr.decode())

Python open default terminal, execute commands, keep open, AND then allow user-input

I'm wanting to open a terminal from a Python script (not one marked as executable, but actually doing python3 myscript.py to run it), have the terminal run commands, and then keep the terminal open and let the user type commands into it.
EDIT (as suggested): I am primarily needing this for Linux (I'm using Xubuntu, Ubuntu and stuff like that). It would be really nice to know Windows 7/8 and Mac methods, too, since I'd like a cross-platform solution in the long-run. Input for any system would be appreciated, however.
Just so people know some useful stuff pertaining to this, here's some code that may be difficult to come up with without some research. This doesn't allow user-input, but it does keep the window open. The code is specifically for Linux:
import subprocess, shlex;
myFilePathString="/home/asdf asdf/file.py";
params=shlex.split('x-terminal-emulator -e bash -c "python3 \''+myFilePathString+'\'; echo \'(Press any key to exit the terminal emulator.)\'; read -n 1 -s"');
subprocess.call(params);
To open it with the Python interpreter running afterward, which is about as good, if not better than what I'm looking for, try this:
import subprocess, shlex;
myFilePathString="/home/asdf asdf/file.py";
params=shlex.split('x-terminal-emulator -e bash -c "python3 -i \''+myFilePathString+'\'"');
subprocess.call(params);
I say these examples may take some time to come up with because passing parameters to bash, which is being opened within another command can be problematic without taking a few steps. Plus, you need to know to use to quotes in the right places, or else, for example, if there's a space in your file path, then you'll have problems and might not know why.
EDIT: For clarity (and part of the answer), I found out that there's a standard way to do this in Windows:
cmd /K [whatever your commands are]
So, if you don't know what I mean try that and see what happens. Here's the URL where I found the information: http://ss64.com/nt/cmd.html

Send commands to an interactive shell from Python

Is there a way to send command to another interactive shell ? Let's take the example of the meterpreter shell used in metasploit. Could it be a way to say command to this shell from python code, as soon as I get control of a computer and have a meterpreter shell to play with ?
I mean All this from python code.

pexpect may be useful: http://pypi.python.org/pypi/pexpect/2.4

It will not be easy at all.
You will have to know if meterpreter has any means for other programs to communicate with it.
If it doesn't, you might want to go through hacking through it, e.g using OS pipes, etc to be able to get it to work.
In any case, the code needed for such communication might be beyond Python's power.

Stty getting insane on using Python subprocess

I am facing a weird problem. Every time I call a particular command cmd via subprocess.Popen(cmd).wait(), the stty gets bad (does not echo my further commands on the shell, newline does not work, etc.) when the command is over. I have to run stty sane to get the stty fine again. What could be the reason for this?
Update The command I am running is starting the elasticsearch process. The command launches the process in the background.

It's possible that the command you're running is emitting some escape sequences into your terminal that are changing its mode or other settings. Programs that need the full terminal capability do that (e.g. text based editors).
Capturing the standard output of the program you're executing and preventing it from going to the screen might help. Have you tried that?

python as a "batch" script (i.e. run commands from python)

I'm working in a windows environment (my laptop!) and I need a couple of scripts that run other programs, pretty much like a windows batch file.
how can I run a command from python such that the program when run, will replace the script? The program is interactive (for instance, unison) and keeps printing lines and asking for user input all the time.
So, just running a program and printing the output won't suffice. The program has to takeover the script's input/output, pretty mcuh like running the command from a .bat file.
I tried os.execl but it keeps telling me "invalid arguments", also, it doesn't find the program name (doesn't search the PATH variable); I have to give it the full path ..?!
basically, in a batch script I can write:
unison profile
how can I achieve the same effect in python?
EDIT:
I found out it can be done with os.system( ... ) and since I cannot accept my own answer, I'm closing the question.
EDIT: this was supposed to be a comment, but when I posted it I didn't have much points.
Thanks Claudiu, that's pretty much what I want, except for a little thing: I want the function to end when the program exits, but when I try it on unison, it doesn't return control to the python script, but to the windows command line environment
>>> os.execlp("unison")
C:\>Usage: unison [options]
or unison root1 root2 [options]
or unison profilename [options]
For a list of options, type "unison -help".
For a tutorial on basic usage, type "unison -doc tutorial".
For other documentation, type "unison -doc topics".
C:\>
C:\>
C:\>
how to get around this?

You should create a new processess using the subprocess module.
I'm not fluent in windows processes but its Popen function is cross-platform, and should be preffered to OS specific solutions.
EDIT: I maintain that you should prefer the Subprocess module to os.* OS specific functions, it is cross-platform and more pythonic (just google it). You can wait for the result easily, and cleanly:
import os
import subprocess
unison = os.path.join(os.path.curdir, "unison")
p = subprocess.Popen(unison)
p.wait()

I found out that os.system does what I want,
Thanks for all that tried to help.
os.system("dir")
runs the command just as if it was run from a batch file

import subprocess
proc = subprocess.Popen(['unison', 'profile'], stderr=subprocess.PIPE,
stdout=subprocess.PIPE, stdin=subprocess.PIPE)
proc.stdin.write('user input')
print proc.stdout.read()
This should help you get started. Please edit your question with more information if you want a more detailed answer!

os.execlp should work. This will search your path for the command. Don't give it any args if they're not necessary:
>>> import os
>>> os.execlp("cmd")
D:\Documents and Settings\Claudiu>Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
D:\Documents and Settings\Claudiu>