winutility.py

"""
  cmd.exe enables virtual terminal mode, but only for itself. It disables VT mode before starting other programs, and also at shutdown.
  This code enables VT mode in Windows 10
  Code taken from https://bugs.python.org/issue30075

"""
import os
import msvcrt
import ctypes

from ctypes import wintypes

kernel32 = ctypes.WinDLL('kernel32', use_last_error=True)

ERROR_INVALID_PARAMETER = 0x0057
ENABLE_VIRTUAL_TERMINAL_PROCESSING = 0x0004

def _check_bool(result, func, args):
    if not result:
        raise ctypes.WinError(ctypes.get_last_error())
    return args

LPDWORD = ctypes.POINTER(wintypes.DWORD)
kernel32.GetConsoleMode.errcheck = _check_bool
kernel32.GetConsoleMode.argtypes = (wintypes.HANDLE, LPDWORD)
kernel32.SetConsoleMode.errcheck = _check_bool
kernel32.SetConsoleMode.argtypes = (wintypes.HANDLE, wintypes.DWORD)

def set_conout_mode(new_mode, mask=0xffffffff):
    # don't assume StandardOutput is a console.
    # open CONOUT$ instead
    fdout = os.open('CONOUT$', os.O_RDWR)
    try:
        hout = msvcrt.get_osfhandle(fdout)
        old_mode = wintypes.DWORD()
        kernel32.GetConsoleMode(hout, ctypes.byref(old_mode))
        mode = (new_mode & mask) | (old_mode.value & ~mask)
        kernel32.SetConsoleMode(hout, mode)
        return old_mode.value
    finally:
        os.close(fdout)

def enable_vt_mode():
    mode = mask = ENABLE_VIRTUAL_TERMINAL_PROCESSING
    try:
        return set_conout_mode(mode, mask)
    except WindowsError as e:
        if e.winerror == ERROR_INVALID_PARAMETER:
            raise NotImplementedError
        raise