I’m trying to run the executable file main.exe which accepts a parameter and runs the function fun in other_file.py. The function fun uses multiprocessing to perform some computationally intensive tasks. It seems like fun is run multiple times when main.exe is called, but the parameter of the function is altered after the first run. Here is a boiled down version of what I’m doing.

main.py:

import sys
import other_file

if __name__ == '__main__':
> other_file.mp.freeze_support()
> param = sys.argv[1]
> with open(r"check1.txt", 'w') as output:       
> > output.write(param)  
> output.close()
> other_file.fun(param)

other_file.py:

import multiprocessing as mp

def fun(param): 
> with open(r"check2.txt", 'w') as output:       
> > output.write(param)  
> output.close()
> # Stuff with multiprocessing below

I converted main.py to the executable main.exe using pyinstaller. When I try to run it via something like the code below check1.txt contains ‘param_val’ as expected. A few moments later check2.txt also contains ‘param_val’ as expected, but then yet another few moments later check2.txt is overwritten and now contains ‘–multiprocessing-fork’. My executable file then throws an error because ‘–multiprocessing-fork’ isn’t an acceptable input for fun.

import subprocess
subprocess.call([r"main.exe", 'param_val'])