Check if a process is running or not on Windows with Python

You can not rely on lock files in Linux or Windows. I would just bite the bullet and iterate through all the running programs. I really do not believe it will be as "expensive" as you think. psutil is an excellent cross-platform python module cable of enumerating all the running programs on a system.

import psutil    "someProgram" in (p.name() for p in psutil.process_iter())

Although @zeller said it already here is an example how to use tasklist. As I was just looking for vanilla python alternatives...

import subprocessdef process_exists(process_name):    call = 'TASKLIST', '/FI', 'imagename eq %s' % process_name    # use buildin check_output right away    output = subprocess.check_output(call).decode()    # check in last line for process name    last_line = output.strip().split('\r\n')[-1]    # because Fail message could be translated    return last_line.lower().startswith(process_name.lower())

and now you can do:

>>> process_exists('eclipse.exe')True>>> process_exists('AJKGVSJGSCSeclipse.exe')False

To avoid calling this multiple times and have an overview of all the processes this way you could do something like:

# get info dict about all running processesimport subprocessoutput = subprocess.check_output(('TASKLIST', '/FO', 'CSV')).decode()# get rid of extra " and split into linesoutput = output.replace('"', '').split('\r\n')keys = output[0].split(',')proc_list = [i.split(',') for i in output[1:] if i]# make dict with proc names as keys and dicts with the extra nfo as valuesproc_dict = dict((i[0], dict(zip(keys[1:], i[1:]))) for i in proc_list)for name, values in sorted(proc_dict.items(), key=lambda x: x[0].lower()):    print('%s: %s' % (name, values))

win32ui.FindWindow(classname, None) returns a window handle if any window with the given class name is found. It raises window32ui.error otherwise.

import win32uidef WindowExists(classname):    try:        win32ui.FindWindow(classname, None)    except win32ui.error:        return False    else:        return Trueif WindowExists("DropboxTrayIcon"):    print "Dropbox is running, sir."else:    print "Dropbox is running..... not."

I found that the window class name for the Dropbox tray icon was DropboxTrayIcon using Autohotkey Window Spy.

See also

MSDN FindWindow