Get keypress for different platforms

get_keypress.py

#!/usr/bin/env python3
# get_keypress.py

import sys
import os


def main():
    try:
        print("press ctrl+c to exit")
        seq = ''

        get_keypress = linux_getch
        if sys.platform in ('linux', 'linux2'):
            get_keypress = linux_getch
        elif sys.platform == "darwin":
            get_keypress = mac_getch
        elif sys.platform == "win32":
            get_keypress = win_getch

        keep_running = True
        while keep_running:
            seq = get_keypress()
            hex_str = str_to_hex(seq)
            print('{} '.format(hex_str), end='', flush=True)
            if seq == '\x03' or seq == '\x04':  # ctrl+c or ctrl+d
                keep_running = False
        print('\n\r')
    except KeyboardInterrupt:
        print("\b\b  ")


# Here are the various escape sequences we can capture
# '\x0d': 'return'
# '\x7f': 'backspace'
# '\x1b': 'escape'
# '\x01': 'ctrl+a'
# '\x02': 'ctrl+b'
# '\x03': 'ctrl+c'
# '\x04': 'ctrl+d'
# '\x05': 'ctrl+e'
# '\x06': 'ctrl+f'
# '\x1a': 'ctrl+z'
# '\x1b\x4f\x50': 'f1'
# '\x1b\x4f\x51': 'f2'
# '\x1b\x4f\x52': 'f3'
# '\x1b\x4f\x53': 'f4'
# '\x1b\x4f\x31\x35\x7e': 'f5'
# '\x1b\x4f\x31\x37\x7e': 'f6'
# '\x1b\x4f\x31\x38\x7e': 'f7'
# '\x1b\x4f\x31\x39\x7e': 'f8'
# '\x1b\x4f\x31\x30\x7e': 'f9'
# '\x1b\x4f\x31\x31\x7e': 'f10'
# '\x1b\x4f\x31\x33\x7e': 'f11'
# '\x1b\x4f\x31\x34\x7e': 'f12'
# '\x1b\x5b\x41': 'up'
# '\x1b\x5b\x42': 'down'
# '\x1b\x5b\x43': 'right'
# '\x1b\x5b\x44': 'left'
# '\x1b\x4f\x46': 'end'
# '\x1b\x4f\x48': 'home'
# '\x1b\x5b\x32\x7e': 'insert'
# '\x1b\x5b\x33\x7e': 'delete'
# '\x1b\x5b\x35\x7e': 'pageup'
# '\x1b\x5b\x36\x7e': 'pagedown'

def linux_getch():
    import sys, tty, termios, fcntl
    stdin_fd = sys.stdin.fileno()
    old_attr = termios.tcgetattr(stdin_fd)
    new_attr = termios.tcgetattr(stdin_fd)
    new_attr[3] = new_attr[3] & ~termios.ICANON & ~termios.ECHO
    termios.tcsetattr(stdin_fd, termios.TCSANOW, new_attr)
    old_flags = fcntl.fcntl(stdin_fd, fcntl.F_GETFL)
    fcntl.fcntl(stdin_fd, fcntl.F_SETFL, old_flags | os.O_NONBLOCK)
    seq = ''
    try:
        tty.setraw(stdin_fd)
        keep_running = True
        while keep_running:
            try:
                key = sys.stdin.read(1)
                if len(key) > 0:
                    seq += key
                elif len(seq) > 0:
                    # this is the first empty read since getting a key
                    return seq
            except IOError:
                pass
        print('\n\r')
    except KeyboardInterrupt:
        print("\b\b  ")
    finally:
        termios.tcsetattr(stdin_fd, termios.TCSAFLUSH, old_attr)
        fcntl.fcntl(stdin_fd, fcntl.F_SETFL, old_flags)


def mac_getch():
    import sys, tty, termios
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    try:
        tty.setraw(sys.stdin.fileno())
        start_pos = sys.stdin.buffer.tell()
        seq = sys.stdin.read(1)
        end_pos = sys.stdin.buffer.tell()
        seq_length = end_pos - start_pos
        if seq_length < 1:
            return ''
        seq += sys.stdin.read(seq_length-1)
        return seq
    except KeyboardInterrupt:
        print("\b\b  ")
        pass
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)


def win_getch():
    import msvcrt
    return msvcrt.getch()


def str_to_hex(seq):
    hex_str = "\\x"
    hex_str += "\\x".join("{:02x}".format(c) for c in seq)
    return hex_str


if __name__ == '__main__':
    main()