multithreading - Python separate threads are killing the whole program -

so wrote script:

def schedule_setup(): # kill old threads should exist global active active = false time.sleep(3) active = true global threadlist threadlist = []  try:     sql = "select time_to_run time_table"     cursor.execute(sql)     results = cursor.fetchall()     row in results:         #row[0].strftime('%h:%m')         t = threading.thread(target=th,args=(row[0].strftime('%h:%m'),))         t.start()         threadlist.append(t)     # join threads main memory     #for count in threadlist:         #count.join()     sql = "update motor set update_schedule = 0"     try:         cursor.execute(sql)         # commit changes in database         db.commit()     except:         # rollback in case there error         print "no worky"         db.rollback() except:     print "error: unable table data" 

it takes times setup on sql , creates scheduled event action. put in beginning thread "killer" active threads if ever call thread again because times have been updated can kill old ones , replace them new. works how want to, action called whole program crashes... here code calls:

def th(run_time):     global active     schedule.every().day.at(run_time).do(run_motor)      while active == true:         schedule.run_pending()         time.sleep(1) 

see how thread checks every second? threads killed when try create new ones, when "run_motor" gets called, afterwords main program supposed loop indefinitely crashes , other threads still going strange me.

you can't sanely kill thread. instead of killing thread, code thread what, , what, want do. way, you'll have no need kill it.

if share car 2 other people , car isn't in driveway, can't kill person driving car. free car use, won't in driveway because killed driver before had chance put back. instead, call them , tell them bring car , let them release car when they're done.