Why Is Python No Longer Waiting for Os.System to Finish

Does Python's os.system() wait for an end of the process?

Yes it does. The return value of the call is the exit code of the subprocess.

How to tell Python to wait until a Windows command from os.system() finishes?

If you don't want to complicate with the subprocess module and you have an estimate for the time it takes to finish, you could simply add a sleep(seconds) after the call:

os.system(COMMAND_START)
sleep(2) -> wait 2 seconds

You can also use the subprocess module:

import subprocess
process = subprocess.Popen(['COMMAND_START'])
exitCode=process.wait()

How to make Python not to wait for the end of the command?

You could create a thread that'll sleep for the specified amount of time. Sleeping threads don't block the main thread, so it'll continue executing.

import threading, time, os

def thread_func(seconds):
    time.sleep(seconds)
    os.system("start alarm.mp3")

threading.Thread(
    target=thread_func,
    args=((alarm_time - now).total_seconds(), ),
    daemon=True
).start()
# Do something else here

os.system will block the execution, but it should be fairly quick.

Python script stops running after running command using os.system()

Change the command like below to see if there are any issues with command.

command_line = 'java -jar "backup.jar" test > /tmp/test.log'

You can verify /tmp/test.log to see if any issues with java command from the log.
os.system waits for response. Same can be achieved with subprocess.call() methods with return status (0 - if successful). To run command in background you can use subprocess.Popen() method.

Python: waiting for external launched process finish

os.system() does wait for its process to complete before returning.

If you are seeing it not wait, the process you are launching is likely detaching itself to run in the background in which case the subprocess.Popen + wait example Dor gave won't help.

Side note: If all you want is subprocess.Popen + wait use subprocess.call:

import subprocess
subprocess.call(('someprog.exe', str(i)))

That is really no different than os.system() other than explicitly passing the command and arguments in instead of handing it over as a single string.

wait for terminal command to finish in python

use communicate:

cmd = subprocess.Popen(command)
cmd.communicate()
# Code to be run after execution finished

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