Non-blocking console input?

For Windows, console only, use the msvcrt module:

import msvcrtnum = 0done = Falsewhile not done:    print(num)    num += 1    if msvcrt.kbhit():        print "you pressed",msvcrt.getch(),"so now i will quit"        done = True

For Linux, this article describes the following solution, it requires the termios module:

import sysimport selectimport ttyimport termiosdef isData():    return select.select([sys.stdin], [], [], 0) == ([sys.stdin], [], [])old_settings = termios.tcgetattr(sys.stdin)try:    tty.setcbreak(sys.stdin.fileno())    i = 0    while 1:        print(i)        i += 1        if isData():            c = sys.stdin.read(1)            if c == '\x1b':         # x1b is ESC                breakfinally:    termios.tcsetattr(sys.stdin, termios.TCSADRAIN, old_settings)

For cross platform, or in case you want a GUI as well, you can use Pygame:

import pygamefrom pygame.locals import *def display(str):    text = font.render(str, True, (255, 255, 255), (159, 182, 205))    textRect = text.get_rect()    textRect.centerx = screen.get_rect().centerx    textRect.centery = screen.get_rect().centery    screen.blit(text, textRect)    pygame.display.update()pygame.init()screen = pygame.display.set_mode( (640,480) )pygame.display.set_caption('Python numbers')screen.fill((159, 182, 205))font = pygame.font.Font(None, 17)num = 0done = Falsewhile not done:    display( str(num) )    num += 1    pygame.event.pump()    keys = pygame.key.get_pressed()    if keys[K_ESCAPE]:        done = True

This is the most awesome solution¹ I've ever seen. Pasted here in case link goes down:

#!/usr/bin/env python'''A Python class implementing KBHIT, the standard keyboard-interrupt poller.Works transparently on Windows and Posix (Linux, Mac OS X).  Doesn't workwith IDLE.This program is free software: you can redistribute it and/or modifyit under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.This program is distributed in the hope that it will be useful,but WITHOUT ANY WARRANTY; without even the implied warranty ofMERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See theGNU General Public License for more details.'''import os# Windowsif os.name == 'nt':    import msvcrt# Posix (Linux, OS X)else:    import sys    import termios    import atexit    from select import selectclass KBHit:    def __init__(self):        '''Creates a KBHit object that you can call to do various keyboard things.        '''        if os.name == 'nt':            pass        else:            # Save the terminal settings            self.fd = sys.stdin.fileno()            self.new_term = termios.tcgetattr(self.fd)            self.old_term = termios.tcgetattr(self.fd)            # New terminal setting unbuffered            self.new_term[3] = (self.new_term[3] & ~termios.ICANON & ~termios.ECHO)            termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.new_term)            # Support normal-terminal reset at exit            atexit.register(self.set_normal_term)    def set_normal_term(self):        ''' Resets to normal terminal.  On Windows this is a no-op.        '''        if os.name == 'nt':            pass        else:            termios.tcsetattr(self.fd, termios.TCSAFLUSH, self.old_term)    def getch(self):        ''' Returns a keyboard character after kbhit() has been called.            Should not be called in the same program as getarrow().        '''        s = ''        if os.name == 'nt':            return msvcrt.getch().decode('utf-8')        else:            return sys.stdin.read(1)    def getarrow(self):        ''' Returns an arrow-key code after kbhit() has been called. Codes are        0 : up        1 : right        2 : down        3 : left        Should not be called in the same program as getch().        '''        if os.name == 'nt':            msvcrt.getch() # skip 0xE0            c = msvcrt.getch()            vals = [72, 77, 80, 75]        else:            c = sys.stdin.read(3)[2]            vals = [65, 67, 66, 68]        return vals.index(ord(c.decode('utf-8')))    def kbhit(self):        ''' Returns True if keyboard character was hit, False otherwise.        '''        if os.name == 'nt':            return msvcrt.kbhit()        else:            dr,dw,de = select([sys.stdin], [], [], 0)            return dr != []# Test    if __name__ == "__main__":    kb = KBHit()    print('Hit any key, or ESC to exit')    while True:        if kb.kbhit():            c = kb.getch()            if ord(c) == 27: # ESC                break            print(c)    kb.set_normal_term()

_{¹Made by Simon D. Levy, part of a compilation of software he has written and released under the Gnu Lesser General Public License.}

Here a solution that runs under linux and windows using a seperate thread:

import sysimport threadingimport timeimport Queuedef add_input(input_queue):    while True:        input_queue.put(sys.stdin.read(1))def foobar():    input_queue = Queue.Queue()    input_thread = threading.Thread(target=add_input, args=(input_queue,))    input_thread.daemon = True    input_thread.start()    last_update = time.time()    while True:        if time.time()-last_update>0.5:            sys.stdout.write(".")            last_update = time.time()        if not input_queue.empty():            print "\ninput:", input_queue.get()foobar()