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How to catch "Python Not Responding" exception?

I used this function below to keep the Python program pressing 'enter" over and over again, but when I click with the mouse, a window appears with "Python Not Responding" and then I have to close the program, so my question is; is there any way for me to catch that with Python?
Code:
def stop():
pyautogui.FAILSAFE = False
while True:
pyautogui.press('enter')
Thanks in advance!

You cannot catch your program crashing as if it were an exception. What you can do in add a delay between sending each key press:
import time
def stop():
pyautogui.FAILSAFE = False
while True:
pyautogui.press('enter')
time.sleep(0.1)

detect key press in python, where each iteration can take more than a couple of seconds?

Edit: The below answer to use keyboard.on_press(callback, suppress=False) works fine in ubuntu without any issues.
But in Redhat/Amazon linux, it fails to work.
I have used the code snippet from this thread
import keyboard # using module keyboard
while True: # making a loop
try: # used try so that if user pressed other than the given key error will not be shown
if keyboard.is_pressed('q'): # if key 'q' is pressed
print('You Pressed A Key!')
break # finishing the loop
except:
break # if user pressed a key other than the given key the loop will break
But the above code requires the each iteration to be executed in nano-seconds. It fails in the below case:
import keyboard # using module keyboard
import time
while True: # making a loop
try: # used try so that if user pressed other than the given key error will not be shown
print("sleeping")
time.sleep(5)
print("slept")
if keyboard.is_pressed('q'): # if key 'q' is pressed
print('You Pressed A Key!')
break # finishing the loop
except:
print("#######")
break # if user pressed a key other than the given key the loop will break

You can make use of event handlers in keyboard module to achieve the desired result.
One such handler is keyboard.on_press(callback, suppress=False):
Which invokes a callback for every key_down event.
You can refer more at keyboard docs
Here is the code you can try:
import keyboard # using module keyboard
import time
stop = False
def onkeypress(event):
global stop
if event.name == 'q':
stop = True
# ---------> hook event handler
keyboard.on_press(onkeypress)
# --------->
while True: # making a loop
try: # used try so that if user pressed other than the given key error will not be shown
print("sleeping")
time.sleep(5)
print("slept")
if stop: # if key 'q' is pressed
print('You Pressed A Key!')
break # finishing the loop
except:
print("#######")
break # if user pressed a key other than the given key the loop will break

for people that might need this in the future, you can use keyboard.wait() which will basically wait untill the key gets pressed
keyboard.wait("o")
print("you pressed the letter o")
Do keep in mind that it blocks code execution after it. if you want to run code if the key is not being pressed i'd suggest doing
if keyboard.is_pressed("0"):
#do stuff
else:
#do other stuff

Edit: never mind, the other answer uses pretty much the same approach
This is what i could come up with, using the same "keyboard" module, see in-code comments below
import keyboard, time
from queue import Queue
# keyboard keypress callback
def on_keypress(e):
keys_queue.put(e.name)
# tell keyboard module to tell us about keypresses via callback
# this callback happens on a separate thread
keys_queue = Queue()
keyboard.on_press(on_keypress)
try:
# run the main loop until some key is in the queue
while keys_queue.empty():
print("sleeping")
time.sleep(5)
print("slept")
# check if its the right key
if keys_queue.get()!='q':
raise Exception("terminated by bad key")
# still here? good, this means we've been stoped by the right key
print("terminated by correct key")
except:
# well, you can
print("#######")
finally:
# stop receiving the callback at this point
keyboard.unhook_all()

You could use a thread
import threading
class KeyboardEvent(threading.Thread):
def run(self):
if keyboard.is_pressed('q'): # if key 'q' is pressed
print('You Pressed A Key!')
break # finishing the loop
keyread = KeyboardEvent()
keyread.start()
This would run in parallel to anything in the main thread and be dedicated to listening for that key press essentially.

How to continue code after thread? Confused about the flow of this code

Sorry I'm new to programming, and don't really understand how this Thread thing works. My goal was for this input to be timed, and I found some code that does that. However, I'm confused about the structure of this Thread because if you are "too slow", the program never continues on to print "checkpoint" as desired. It just sort of... freezes... Why is it getting stuck?
import time
from threading import Thread
answer = None
def check():
# waits for user input for 3 seconds
for i in range(3):
time.sleep(1)
if answer != None:
return
print('too slow')
Thread(target = check).start()
answer = input("Input something: ")
print('checkpoint')
One thing I tried is:
t = Thread(target = check)
t.start()
answer = input("Input something: ")
# also tried t.join()
if t.is_alive:
print('hi')
I tried to solve this program by trying to raise and catch an exception. However, I couldn't catch the exception. How do I catch it? (Or is there another solution to the problem I am having?)
import time
from threading import Thread
answer = None
def check():
# waits for user input for 3 seconds
for i in range(3):
time.sleep(1)
if answer != None:
return
print('too slow')
# was hoping to catch this as an exception
raise TimeoutError
# starts new thread
Thread(target = check).start()
# prompts user for an input
answer = input("Input something: ")
print('checkpoint')
What's good:
When you type something into the input prompt within 3 seconds, it prints "checkpoint" and continues on with code.
What's bad:
If you take "too long", the program prints "too slow!" as expected, BUT then it stops executing code and just sort of... freezes. So to try to fix this, I was hoping to raise a Timeout Error and then catch it, but I don't know how to catch it. This didn't catch the error:
try:
Thread(target = check).start()
except:
pass
This didn't either:
try:
answer = input("Input something: ")
except:
pass
Could I get some help? Thank you!
Edit: Forgot to mention that I am using linux so a lot of the solutions for my application did not work for me like msvcrt or keyboard. And modules that do work for Linux seem not to be "non-blocking."

You should think of the two threads as two separate programs, but sharing the same variables.
Thread 1 consists of everything that isn't indented in your code. It launches a thread, then it waits for user input, then it prints "checkpoint". Then it's done.
Thread 2 consists of the function check. It checks to see if the variable isn't None. If that happens it's done. If that doesn't happen in three seconds, it prints "too slow" and now it's done.
Neither thread "knows" what the other one is doing, except they share one variable, answer.
The program as a whole will exit when all its threads are finished.
That's it. That's what you've written. So if you type something, the program exits because Thread 1 will always exit after you type something. Thread 2 exits once it sees the variable isn't None.
If you don't type anything, Thread 1 will just sit there and wait for you, forever. That's how the input function works. Thread 2 will exit after 3 seconds or less, but that doesn't affect Thread 1.
You can't throw an Exception from one Thread to another. So you can't throw an exception from Thread 2 and have Thread 1 handle it.
Have you tried typing something AFTER the message "too slow" appears? When you do, Thread 1 (and therefore your program) will exit.
The bottom line is that you can't use the input function in cases like this, because that function blocks the flow of its thread until the user types something. There is nothing any other thread can do to make it continue.

DISCLAIMER: THIS DOESN'T ANSWER THE QUESTION BUT IN CASE YOU WANT TO KNOW HOW I GOT AROUND THE "INPUT" THING, HERE IS MY SOLUTION TO THE PROBLEM.
Actually I found something that works! It's a little strange but it works for what I am trying to do, thanks to #rayryeng 's answer here: detect key press in python?.
Problem Statement: Continue the program when 'enter' is pressed, and timeout if input takes too long. This does exactly that, although it displays strangely to the console... PS. I had to run this in my terminal as 'sudo' or it wouldn't work in my scratch file for whatever reason.
import curses
import os
from time import time, sleep
def main(win):
win.nodelay(True) # True turns on "non-blocking"
key=""
win.clear()
win.addstr("Please press 'Enter' to continue:")
start_time = time()
while 1:
end_time = time()
try:
if end_time-start_time > 5: # 5 seconds
return 'You are too slow!'
else:
key = win.getkey()
if key == os.linesep:
return 'OK. Continuing on...'
except Exception as e:
# No input
pass
p = curses.wrapper(main)
print(p) #-> either 'You are too slow!' or 'OK. Continuing on...'
I guess if you actually wanted to store the input you can modify it to be something like this:
def main(win):
win.nodelay(True) # True turns on "non-blocking"
key=""
win.clear()
win.addstr("Please press 'Enter' to continue:")
start_time = time()
while 1:
end_time = time()
try:
if end_time-start_time > 5: # 5 seconds
return 'You are too slow!'
else:
key = win.getkey() # gets a single char
if key: # == os.linesep:
return str(key) # returns that single char
except Exception as e:
# No input
pass
p = curses.wrapper(main)
print(p) #-> either 'You are too slow!' or character entered
And if you want to store more characters you could do something like this (just be aware that it also stores the "enter" key in the resulting string):
import curses
import os
from time import time, sleep
def main(win):
win.nodelay(True) # True turns on "non-blocking"
key=""
win.clear()
win.addstr("Please press 'Enter' to continue:")
start_time = time()
result = key # empty string
while 1:
end_time = time()
try:
if end_time-start_time > 5: # 5 seconds
return 'You are too slow!'
else:
key = win.getkey() # gets single char
result = result + str(key) # adds characters to the empty string
if key == os.linesep: # "new line"
return result
except Exception as e:
# No input
pass
p = curses.wrapper(main)
print(p) #-> either 'You are too slow!' or characters entered

Whats wrong with this code loop in python pynput loop indent wrong

7.0 and I am wanting to know what I've done wrong with this code. I want it to loop infinitely and say vcmine start but I've done I've tried using for while and tried spamming the code over and over I just want it to print this code into a game so that I don't have to be at my pc but I can only get it to work with it only saying it once please help I've something wrong and I don't know what
from pynput.keyboard import Key, Controller
import time
keyboard = Controller ()
while True:
for char in "vcmine start":
keyboard.press(char)
keyboard.release(char)
time.sleep(0.03)
break
while True:
keyboard.press(key.enter)
keyboard.press(key.enter)
break

I think what you want is :
from pynput.keyboard import Key, Controller
import time
keyboard = Controller ()
while True:
for char in "vcmine start":
keyboard.press(char)
keyboard.release(char)
time.sleep(0.03)
keyboard.press(key.enter)
time.sleep(0.03)
keyboard.press(key.enter)
time.sleep(0.03)

Stop an infinite while loop repeatedly invoking os.system

Thank you guys for seeing my post.
First, the following is my code:
import os
print("You can create your own message for alarm.")
user_message = input(">> ")
print("\n<< Sample alarm sound >>")
for time in range(0, 3):
os.system('say ' + user_message) # this code makes sound.
print("\nOkay, The alarm has been set.")
"""
##### My problem is here #####
##### THIS IS NOT STOPPED #####
while True:
try:
os.system('say ' + user_message)
except KeyboardInterrupt:
print("Alarm stopped")
exit(0)
"""
My problem is that Ctrl + C does not work!
I tried changing position of try block, and making signal(SIGINT) catching function.
But those also does not work.
I have seen https://stackoverflow.com/a/8335212/5247212, https://stackoverflow.com/a/32923070/5247212, and other several answers about this problem.
I am using MAC OS(10.12.3) and python 3.5.2.

This is expected behaviour, as os.system() is a thin wrapper around the C function system(). As noted in the man page, the parent process ignores SIGINT during the execution of the command. In order to exit the loop, you have to manually check the exit code of the child process (this is also mentioned in the man page):
import os
import signal
while True:
code = os.system('sleep 1000')
if code == signal.SIGINT:
print('Awakened')
break
However, the preferred (and more pythonic) way to achieve the same result is to use the subprocess module:
import subprocess
while True:
try:
subprocess.run(('sleep', '1000'))
except KeyboardInterrupt:
print('Awakened')
break
Your code would then look like something like this:
import subprocess
print("You can create your own message for alarm.")
user_message = input(">> ")
print("\n<< Sample alarm sound >>")
for time in range(0, 3):
subprocess.run(['say', user_message]) # this code makes sound.
print("\nOkay, The alarm has been set.")
while True:
try:
subprocess.run(['say', user_message])
except KeyBoardInterrupt:
print("Alarm terminated")
exit(0)
As an added note, subprocess.run() is only available in Python 3.5+. You can use subprocess.call() to achieve the same effect in older versions of Python.

Also catch "SystemExit"
except (KeyboardInterrupt, SystemExit):
print("Alarm stopped")

The problem seems to be that Ctrl+C is captured by the subprocess you call via os.system. This subprocess reacts correspondingly, probably by terminating whatever it is doing. If so, the return value of os.system() will be not zero. You can use that to break the while loop.
Here's an example that works with me (substituting say by sleep):
import os
import sys
while True:
try:
if os.system('sleep 1 '):
raise KeyboardInterrupt
except KeyboardInterrupt:
print("Alarm stopped")
sys.exit(0)

If Ctrl-C is captured by the subprocess, which is the case here, the simplest solution is to check the return value of os.system(). For example in my case it returns value of 2 if Ctrl-C stops it, which is a SIGINT code.
import os
while True:
r = os.system(my_job)
if r == 2:
print('Stopped')
break
elif r != 0:
print('Some other error', r)