class _Getch:
"""Gets a single character from standard input. Does not echo to the
screen."""
def __init__(self):
try:
self.impl = _GetchWindows()
except ImportError:
self.impl = _GetchUnix()
def __call__(self): return self.impl()
class _GetchUnix:
"""Fetch and character using the termios module."""
def __init__(self):
import tty, sys
from select import select
def __call__(self):
import sys, tty, termios
from select import select
fd = sys.stdin.fileno()
old_settings = termios.tcgetattr(fd)
try:
tty.setraw(sys.stdin.fileno())
# [ Wait until ready for reading,
# wait until ready for writing
# wait for an "exception condition" ]
# The below line times out after 1 second
# This can be changed to a floating-point value if necessary
[i, o, e] = select([sys.stdin.fileno()], [], [], 1)
if i:
ch = sys.stdin.read(1)
else:
ch = None
finally:
termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
return ch
class _GetchWindows:
"""Fetch a character using the Microsoft Visual C Runtime."""
def __init__(self):
import msvcrt
def __call__(self):
import msvcrt
import time
# Delay timeout to match UNIX behaviour
time.sleep(1)
# Check if there is a character waiting, otherwise this would block
if msvcrt.kbhit():
return msvcrt.getch()
else:
return
getch = _Getch()
