NickName:shlomiLan Ask DateTime:2017-01-03T06:04:30

Check if a Python script is already running in Windows

What is the best/easiest why to check if a specific Python script already running in Windows?

I have a script that goes over all files in a folder and copies them to another folder (sort to Movie or TV Shows folder). I want to make sure when the script starts that there isn't another process (of the same script) that is already running, so I wouldn't have issues with 2 scripts that are trying to move the same files.

I have tried to create a file in the start of the script and deleting it when the script finishes, but I got into problems when the script crashes and/or throws an error.

I know that I can use psutil, but then I will get the process name (python.exe) and I'm looking for a why to distinguish if the Python process is running my script or another program.

Copyright Notice：Content Author:「shlomiLan」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/41433819/check-if-a-python-script-is-already-running-in-windows

Answers

Roland Smith 2017-01-02T22:26:08

You can use psutil.Process().cmdline() to see the complete command line of a process.\n\nAlternatively, you could lock the files you're working on. See the answer to this question how to do this on ms-windows. The thing with locks is that you have to be careful to remove them, especially when an error occurs.",

user11394093 2019-04-22T09:25:08

For Windows o.s. you can use timestamp.txt file\n\ntimestamp = 'timestamp.txt'\n...\nelif windows:\n try:\n new_timestamp = False\n if not os.path.exists(timestamp):\n new_timestamp = True\n try:\n with open(timestamp, 'a') as f_timestamp:\n f_timestamp.write(str(int_t0))\n except IOError as e:\n out1 = 'M. Cannot open file for writing. Error: %s - %s.' \\\n % (e.logfile, e.strerror) + ' -> Exit code 3'\n logging.error(out1)\n sys.exit(3)\n\n if not new_timestamp and os.path.exists(timestamp):\n out1 = 'N. Script ' + __file__ + ' is already running.'\n print(out1)\n logging.error(out1)\n sys.exit(0)\n\n except IOError as e:\n out1 = 'J. Cannot open file. Error: %s - %s.' \\\n % (e.filepath, e.strerror) + ' -> Exit code 4'\n logging.error(out1)\n\n...\ntry:\n f_timestamp.close()\n os.remove(timestamp)\nexcept OSError as e:\n logging.error('B. Cannot delete ' + timestamp + \\\n ' Error: %s - %s.' % (e.filename, e.strerror))\n",

Marat 2017-01-02T22:30:18

Use lockfile. It is cross-platform, uses native OS functions and much more robust than any home-brewn lock file creation schemas",