subprocess.Popen Example

test_subprocess.py

import subprocess

cmd = ['/full/path/to/python', '/full/path/to/your/process']
print('running command: "{0}"'.format(cmd))  # output the command.

# Here, we join the STDERR of the application with the STDOUT of the application.
process = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
outLines = []  # We use this just in case you want to see the output of the program later. It's not required.
for line in iter(process.stdout.readline, ''):
    print line.rstrip()
    outLines.append(line)  # Again, only if you need it

returncode = process.wait()  # Wait for the underlying program to finish normally.

print('sub-process exited with code: {0}'.format(returncode))

In python3, update line 9 to the following:

for line in iter(process.stdout.readline, b''):
    print(line.rstrip())
    outLines.append(line)  # Again, only if you need it