Taking in multiple inputs for a fixed time [duplicate]

This solution is platform-independent and immediately interrupts typing to inform about an existing timeout. It doesn't have to wait until the user hits ENTER to find out a timeout occured. Besides informing the user just-in-time this ensures no input after the timeout stepped in is further processed.

Features

• Platform independent (Unix / Windows).
• StdLib only, no external dependencies.
• Threads only, no Subprocesses.
• Immediate interrupt at timeout.
• Clean shutdown of prompter at timeout.
• Unlimited inputs possible during time span.
• Easy expandable PromptManager class.
• Program may resume after timeout, multiple runs of prompter instances possible without program restart.

This answer uses a threaded manager instance, which mediates between aseparate prompting thread and the MainThread. The manager-thread checks for timeout and forwards inputs from the prompt-thread to the parent-thread. This design enables easy modification in case MainThread would need to be non-blocking (changes in _poll to replace blocking queue.get()).

On timeout the manager thread asks for ENTER to continue and uses anthreading.Event instance to assure the prompt-thread shuts down beforecontinuing. See further details in the doc-texts of the specific methods:

from threading import Thread, Eventfrom queue import Queue, Emptyimport timeSENTINEL = object()class PromptManager(Thread):    def __init__(self, timeout):        super().__init__()        self.timeout = timeout        self._in_queue = Queue()        self._out_queue = Queue()        self.prompter = Thread(target=self._prompter, daemon=True)        self.start_time = None        self._prompter_exit = Event()  # synchronization for shutdown        self._echoed = Event()  # synchronization for terminal output    def run(self):        """Run in worker-thread. Start prompt-thread, fetch passed        inputs from in_queue and check for timeout. Forward inputs for        `_poll` in parent. If timeout occurs, enqueue SENTINEL to        break the for-loop in `_poll()`.        """        self.start_time = time.time()        self.prompter.start()        while self.time_left > 0:            try:                txt = self._in_queue.get(timeout=self.time_left)            except Empty:                self._out_queue.put(SENTINEL)            else:                self._out_queue.put(txt)        print("\nTime is out! Press ENTER to continue.")        self._prompter_exit.wait()    @property    def time_left(self):        return self.timeout - (time.time() - self.start_time)    def start(self):        """Start manager-thread."""        super().start()        self._poll()    def _prompter(self):        """Prompting target function for execution in prompter-thread."""        while self.time_left > 0:            self._in_queue.put(input('>$ '))            self._echoed.wait()  # prevent intermixed display            self._echoed.clear()        self._prompter_exit.set()    def _poll(self):        """Get forwarded inputs from the manager-thread executing `run()`        and process them in the parent-thread.        """        for msg in iter(self._out_queue.get, SENTINEL):            print(f'you typed: {msg}')            self._echoed.set()        # finalize        self._echoed.set()        self._prompter_exit.wait()        self.join()if __name__ == '__main__':    pm = PromptManager(timeout=5)    pm.start()

Example Output:

>$ Helloyou typed: Hello>$ WorTime is out! Press ENTER to continue.Process finished with exit code 0

Note the timeout-message here popped up during the attempt of typing "World".

You can use the poll() method (tested on Linux):

import select,sysdef timed_input(sec):    po= select.poll()   # creating a poll object    # register the standard input for polling with the file number     po.register(sys.stdin.fileno(), select.POLLIN)      while True:        # start the poll        events= po.poll(sec*1000)   # timeout: milliseconds        if not events:            print("\n Sorry, it's too late...")            return ""        for fno,ev in events:     #  check the events and the corresponding fno              if fno == sys.stdin.fileno():  # in our case this is the only one                return(input())s=timed_input(10)print("From keyboard:",s)  

The stdin buffers the pressed keys, and the input() function read that buffer at once.

Here's a short way of doing that, Without using Signals, NOTE: While loop will be blocked until the user has inputted something and then check for condition.

from datetime import datetime, timedeltat = 5  # You can type for 5 secondsdef timeup():    final_time = datetime.now() + timedelta(seconds=t)    print("You can enter now for" + str(t) + " seconds")    while datetime.now() < final_time:        input()    print("STOP TYPING")timeup()