Skip to content

Instantly share code, notes, and snippets.

@hapylestat
Created November 4, 2018 16:00
Show Gist options
  • Select an option

  • Save hapylestat/1101cc1a5bde125cc5d56c6a401a4f35 to your computer and use it in GitHub Desktop.

Select an option

Save hapylestat/1101cc1a5bde125cc5d56c6a401a4f35 to your computer and use it in GitHub Desktop.
#!/us/sbin/env python3
def read_single_keypress():
"""Waits for a single keypress on stdin.
This is a silly function to call if you need to do it a lot because it has
to store stdin's current setup, setup stdin for reading single keystrokes
then read the single keystroke then revert stdin back after reading the
keystroke.
Returns the character of the key that was pressed (zero on
KeyboardInterrupt which can happen when a signal gets handled)
"""
import termios, fcntl, sys, os
fd = sys.stdin.fileno()
# save old state
flags_save = fcntl.fcntl(fd, fcntl.F_GETFL)
attrs_save = termios.tcgetattr(fd)
# make raw - the way to do this comes from the termios(3) man page.
attrs = list(attrs_save) # copy the stored version to update
# iflag
attrs[0] &= ~(termios.IGNBRK | termios.BRKINT | termios.PARMRK
| termios.ISTRIP | termios.INLCR | termios. IGNCR
| termios.ICRNL | termios.IXON )
# oflag
attrs[1] &= ~termios.OPOST
# cflag
attrs[2] &= ~(termios.CSIZE | termios. PARENB)
attrs[2] |= termios.CS8
# lflag
attrs[3] &= ~(termios.ECHONL | termios.ECHO | termios.ICANON
| termios.ISIG | termios.IEXTEN)
termios.tcsetattr(fd, termios.TCSANOW, attrs)
# turn off non-blocking
fcntl.fcntl(fd, fcntl.F_SETFL, flags_save & ~os.O_NONBLOCK)
# read a single keystroke
try:
ret = sys.stdin.read(1) # returns a single character
except KeyboardInterrupt:
ret = '\x03'
finally:
# restore old state
termios.tcsetattr(fd, termios.TCSAFLUSH, attrs_save)
fcntl.fcntl(fd, fcntl.F_SETFL, flags_save)
return ret
while True:
ch = read_single_keypress()
print(str(ord(ch)) + " ", end='', flush=True)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment