Error in executing .jar file from a Python script called from another Python script, as a subprocess
Question: This is in extension to a resolved post that I had posted
[here](http://stackoverflow.com/questions/30766563/error-in-executing-a-jar-
file-in-remote-machine). I have a `python script` which has the following
`jar` execution code in it(alongwith some other codes):

**python_file2.py**

    
    
    import os
    cmd_txt = "ssh -i pem_file.pem user@" + host_name + " 'cd /user/folder1/ && java -cp jar-file.jar'"
    os.system(cmd_txt)
    

Now this `python script` file(python_file2.py) is called as a `subprocess`
from another `python script`.

**Main_script.py**

    
    
    ret = subprocess.Popen([sys.executable,"python_file2.py"])
    

When I run this **Main_script.py** then the execution of the `jar` file from
`python_file2.py` seems to get hanged. When I run the first script alone it
works fine but when I try to execute it as `subprocess` then the `jar`
execution hangs and timeouts.

What could be a possible reason for this `jar` execution getting hanged when
executed from inside a `subprocess` script? All I want to is run a jar file
which is present on remote machine from inside a python script which is ran as
a `subprocess`.


Answer: Use `subprocess.call` instead of `subprocess.Popen`:

    
    
    ret = subprocess.call([sys.executable,"python_file2.py"])
    assert not ret, ret
    

