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Check if python script running from another python script linux

I have actualy python script running on background, you can see how it's displayed when i use command "ps -aux" :
root 405 0.0 2.6 34052 25328 ? S 09:52 0:04 python3 -u /opt/flask_server/downlink_server/downlink_manager.py
i want to check if this script are running from another python script, so i try to us psutil module, but it just detect that python3 are running but not my script precisely !
there is my python script :
import os
import psutil
import time
import logging
import sys
for process in psutil.process_iter():
if process.cmdline() == ['python3', '/opt/flask_server/downlink_server/downlink_manager.py']:
print('Process found: exiting.')
It's look like simple, but trust me, i already try other function proposed on another topic, like this :
def find_procs_by_name(name):
"Return a list of processes matching 'name'."
ls = []
for p in psutil.process_iter(attrs=["name", "exe", "cmdline"]):
if name == p.info['name'] or \
p.info['exe'] and os.path.basename(p.info['exe']) == name or \
p.info['cmdline'] and p.info['cmdline'][0] == name:
ls.append(p)
return ls
ls = find_procs_by_name("downlink_manager.py")
But this function didn't fin my script, it's work, when i search python3 but not the name of the script.
Of course i try to put all the path of the script but nothing, can you please hepl me ?

I resolve the issue with this modification :
import psutil
proc_iter = psutil.process_iter(attrs=["pid", "name", "cmdline"])
process = any("/opt/flask_server/downlink_server/downlink_manager.py" in p.info["cmdline"] for p in proc_iter)
print(process)

Python script runs fine from terminal but crashes when run from crontab

I have a simple python script that takes screenshots of a computer that is running Ubuntu. I want it to run automatically on startup, so I put #reboot python3 /bin/program.py in the non-sudo version of crontab.
The program works fine when run from terminal, but gives the error pyscreenshot.err.FailedBackendError. I put it in a try loop, and had it write all exceptions to a file, and that's how I found the error message, "All backends failed."
It has something to do with the program 'pyscreenshot' not working correctly.
import pyscreenshot as screen
import os
from numpy import random
from time import sleep
from os.path import expanduser
TMP_SCREEN_PATH = expanduser('~') + '/.UE/tmp.png'
LOG_FILE_PATH = expanduser('~') + '/.UE/log.txt'
GRAB_DELAY_RANGE = (1, 10)
def screenshot(save_path=TMP_SCREEN_PATH):
img = screen.grab()
img.save(save_path)
def delay(delay_range):
sleep_time = random.randint(delay_range[0], delay_range[1])
print(f"Sleeping for {sleep_time} seconds")
sleep(sleep_time)
def main():
try:
while True:
screenshot()
delay(GRAB_DELAY_RANGE)
except KeyboardInterrupt:
print("Nope")
main()
except Exception as e:
print(e)
with open(LOG_FILE_PATH, 'a') as f:
f.write(str(type(e))+str(e)+'\n')
sleep(5)
main()
f = open(LOG_FILE_PATH, 'w+')
f.write('Startup')
f.close()
main()
I need one of the following solutions:
Simply fix the problem
Another way to run a program at startup
A different module to take screenshots with
Any help is appreciated, thanks

If the user that the cron job runs as is also logged in on the console (you mention a reboot, so I'm guessing that you have enabled autologin), then your cron job might work if you also add:
os.environ["DISPLAY"] = ":0"
This worked for me on Ubuntu in a test using cron and a simplified version of your script:
import os
import pyscreenshot as screen
os.environ["DISPLAY"] = ":0"
img = screen.grab()
img.save("/tmp/test.png")
If it doesn't work for you, then you might also have to try setting the value of the XAUTHORITY environment variable to the value found in the environment of the user's interactive processes, which could be extracted using the psutil package, but let's hope this isn't needed.

Subprocess to open python file and return data

I am trying to use Python to open another file. This file is going to start up a socket and create threads for listening for additional connections, and threads for sending/receiving data. The main thread will not return.
However, if the setup of sockets fail, I want to return a error code to the other python script that executed the subprocess.
main.py
py3output = subprocess.check_output(['python3', 'py3.py'])
print('py3 said:' + str(py3output))
py3.py
def returnme():
return 10
returnme()
When I run this, it prints:
py3 said:b''
I am just trying to figure out how to get the return value back to the main calling program.

To return an exit code n back to the OS, you need sys.exit(n). But seems like you do not want to check the exit code but the stdout otput. So your program might need to rewrite to:
def returnme():
return 10
print(returnme())

You should only return a string as a standard output using following code:
sample.py
import sys
def returnme():
sys.stdout.write(str(10))
sys.stdout.flush()
returnme()
main.py
from subprocess import check_output
output = check_output(['python','sample.py'])
print('Sample.py says :' + output)

How can python wait for a batch SGE script finish execution?

I have a problem I'd like you to help me to solve.
I am working in Python and I want to do the following:
call an SGE batch script on a server
see if it works correctly
do something
What I do now is approx the following:
import subprocess
try:
tmp = subprocess.call(qsub ....)
if tmp != 0:
error_handler_1()
else:
correct_routine()
except:
error_handler_2()
My problem is that once the script is sent to SGE, my python script interpret it as a success and keeps working as if it finished.
Do you have any suggestion about how could I make the python code wait for the actual processing result of the SGE script ?
Ah, btw I tried using qrsh but I don't have permission to use it on the SGE
Thanks!

From your code you want the program to wait for job to finish and return code, right? If so, the qsub sync option is likely what you want:
http://gridscheduler.sourceforge.net/htmlman/htmlman1/qsub.html

Additional Answer for an easier processing:
By using the python drmaa module : link which allows a more complete processing with SGE.
A functioning code provided in the documentation is here: [provided you put a sleeper.sh script in the same directory]
please notice that the -b n option is needed to execute a .sh script, otherwise it expects a binary by default like explained here
import drmaa
import os
def main():
"""Submit a job.
Note, need file called sleeper.sh in current directory.
"""
s = drmaa.Session()
s.initialize()
print 'Creating job template'
jt = s.createJobTemplate()
jt.remoteCommand = os.getcwd()+'/sleeper.sh'
jt.args = ['42','Simon says:']
jt.joinFiles=False
jt.nativeSpecification ="-m abe -M mymail -q so-el6 -b n"
jobid = s.runJob(jt)
print 'Your job has been submitted with id ' + jobid
retval = s.wait(jobid, drmaa.Session.TIMEOUT_WAIT_FOREVER)
print('Job: {0} finished with status {1}'.format(retval.jobId, retval.hasExited))
print 'Cleaning up'
s.deleteJobTemplate(jt)
s.exit()
if __name__=='__main__':
main()

How to terminate process from Python using pid?

I'm trying to write some short script in python which would start another python code in subprocess if is not already started else terminate terminal & app (Linux).
So it looks like:
#!/usr/bin/python
from subprocess import Popen
text_file = open(".proc", "rb")
dat = text_file.read()
text_file.close()
def do(dat):
text_file = open(".proc", "w")
p = None
if dat == "x" :
p = Popen('python StripCore.py', shell=True)
text_file.write( str( p.pid ) )
else :
text_file.write( "x" )
p = # Assign process by pid / pid from int( dat )
p.terminate()
text_file.close()
do( dat )
Have problem of lacking knowledge to name proces by pid which app reads from file ".proc".
The other problem is that interpreter says that string named dat is not equal to "x" ??? What I've missed ?

Using the awesome psutil library it's pretty simple:
p = psutil.Process(pid)
p.terminate() #or p.kill()
If you don't want to install a new library, you can use the os module:
import os
import signal
os.kill(pid, signal.SIGTERM) #or signal.SIGKILL
See also the os.kill documentation.
If you are interested in starting the command python StripCore.py if it is not running, and killing it otherwise, you can use psutil to do this reliably.
Something like:
import psutil
from subprocess import Popen
for process in psutil.process_iter():
if process.cmdline() == ['python', 'StripCore.py']:
print('Process found. Terminating it.')
process.terminate()
break
else:
print('Process not found: starting it.')
Popen(['python', 'StripCore.py'])
Sample run:
$python test_strip.py #test_strip.py contains the code above
Process not found: starting it.
$python test_strip.py
Process found. Terminating it.
$python test_strip.py
Process not found: starting it.
$killall python
$python test_strip.py
Process not found: starting it.
$python test_strip.py
Process found. Terminating it.
$python test_strip.py
Process not found: starting it.
Note: In previous psutil versions cmdline was an attribute instead of a method.

I wanted to do the same thing as, but I wanted to do it in the one file.
So the logic would be:
if a script with my name is running, kill it, then exit
if a script with my name is not running, do stuff
I modified the answer by Bakuriu and came up with this:
from os import getpid
from sys import argv, exit
import psutil ## pip install psutil
myname = argv[0]
mypid = getpid()
for process in psutil.process_iter():
if process.pid != mypid:
for path in process.cmdline():
if myname in path:
print "process found"
process.terminate()
exit()
## your program starts here...
Running the script will do whatever the script does. Running another instance of the script will kill any existing instance of the script.
I use this to display a little PyGTK calendar widget which runs when I click the clock. If I click and the calendar is not up, the calendar displays. If the calendar is running and I click the clock, the calendar disappears.

So, not directly related but this is the first question that appears when you try to find how to terminate a process running from a specific folder using Python.
It also answers the question in a way(even though it is an old one with lots of answers).
While creating a faster way to scrape some government sites for data I had an issue where if any of the processes in the pool got stuck they would be skipped but still take up memory from my computer. This is the solution I reached for killing them, if anyone knows a better way to do it please let me know!
import pandas as pd
import wmi
from re import escape
import os
def kill_process(kill_path, execs):
f = wmi.WMI()
esc = escape(kill_path)
temp = {'id':[], 'path':[], 'name':[]}
for process in f.Win32_Process():
temp['id'].append(process.ProcessId)
temp['path'].append(process.ExecutablePath)
temp['name'].append(process.Name)
temp = pd.DataFrame(temp)
temp = temp.dropna(subset=['path']).reset_index().drop(columns=['index'])
temp = temp.loc[temp['path'].str.contains(esc)].loc[temp.name.isin(execs)].reset_index().drop(columns=['index'])
[os.system('taskkill /PID {} /f'.format(t)) for t in temp['id']]