Python curses 模块，tigetnum() 实例源码

def supported(self):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        # assuming stderr
        # isatty() returns False when SSHd into Win32 machine
        if 'CYGWIN' in os.environ:
            return True
        if not sys.stderr.isatty():
            return False # auto color only on TTYs
        try:
            import curses
            curses.setupterm()
            return curses.tigetnum("colors") > 2
        except:
            # guess false in case of error
            return False

def supported(self):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        # assuming stderr
        # isatty() returns False when SSHd into Win32 machine
        if 'CYGWIN' in os.environ:
            return True
        if not sys.stderr.isatty():
            return False # auto color only on TTYs
        try:
            import curses
            curses.setupterm()
            return curses.tigetnum("colors") > 2
        except:
            # guess false in case of error
            return False

def __has_colors(stream):
        """
        Is tty output check
        :param object stream: input stream
        :return: bool
        """

        if not hasattr(stream, "isatty"):
            return False
        # noinspection PyUnresolvedReferences
        if not stream.isatty():
            return False  # auto color only on TTYs
        # noinspection PyBroadException
        try:
            import curses
            curses.setupterm()
            return curses.tigetnum("colors") > 2
        except Exception:
            # guess false in case of error
            return False

def supported(cls, stream=sys.stdout):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except:
                # guess false in case of error
                return False

def enable_pretty_logging():
    """Turns on formatted logging output as configured."""
    if (options.log_to_stderr or
        (options.log_to_stderr is None and not options.log_file_prefix)):
        # Set up color if we are in a tty and curses is installed
        color = False
        if curses and sys.stderr.isatty():
            try:
                curses.setupterm()
                if curses.tigetnum("colors") > 0:
                    color = True
            except:
                pass
        channel = logging.StreamHandler()
        channel.setFormatter(_LogFormatter(color=color))
        logging.getLogger().addHandler(channel)

    if options.log_file_prefix:
        channel = logging.handlers.RotatingFileHandler(
            filename=options.log_file_prefix,
            maxBytes=options.log_file_max_size,
            backupCount=options.log_file_num_backups)
        channel.setFormatter(_LogFormatter(color=False))
        logging.getLogger().addHandler(channel)

def _height_and_width(self):
        """Return a tuple of (terminal height, terminal width).

        Start by trying TIOCGWINSZ (Terminal I/O-Control: Get Window Size),
        falling back to environment variables (LINES, COLUMNS), and returning
        (None, None) if those are unavailable or invalid.

        """
        # tigetnum('lines') and tigetnum('cols') update only if we call
        # setupterm() again.
        for descriptor in self._init_descriptor, sys.__stdout__:
            try:
                return struct.unpack(
                        'hhhh', ioctl(descriptor, TIOCGWINSZ, '\000' * 8))[0:2]
            except IOError:
                # when the output stream or init descriptor is not a tty, such
                # as when when stdout is piped to another program, fe. tee(1),
                # these ioctls will raise IOError
                pass
        try:
            return int(environ.get('LINES')), int(environ.get('COLUMNS'))
        except TypeError:
            return None, None

def number_of_colors(self):
        """Return the number of colors the terminal supports.

        Common values are 0, 8, 16, 88, and 256.

        Though the underlying capability returns -1 when there is no color
        support, we return 0. This lets you test more Pythonically::

            if term.number_of_colors:
                ...

        We also return 0 if the terminal won't tell us how many colors it
        supports, which I think is rare.

        """
        # This is actually the only remotely useful numeric capability. We
        # don't name it after the underlying capability, because we deviate
        # slightly from its behavior, and we might someday wish to give direct
        # access to it.
        colors = tigetnum('colors')  # Returns -1 if no color support, -2 if no
                                     # such cap.
        #  self.__dict__['colors'] = ret  # Cache it. It's not changing.
                                          # (Doesn't work.)
        return colors if colors >= 0 else 0

def _height_and_width(self):
        """Return a tuple of (terminal height, terminal width).

        Start by trying TIOCGWINSZ (Terminal I/O-Control: Get Window Size),
        falling back to environment variables (LINES, COLUMNS), and returning
        (None, None) if those are unavailable or invalid.

        """
        # tigetnum('lines') and tigetnum('cols') update only if we call
        # setupterm() again.
        for descriptor in self._init_descriptor, sys.__stdout__:
            try:
                return struct.unpack(
                        'hhhh', ioctl(descriptor, TIOCGWINSZ, '\000' * 8))[0:2]
            except IOError:
                # when the output stream or init descriptor is not a tty, such
                # as when when stdout is piped to another program, fe. tee(1),
                # these ioctls will raise IOError
                pass
        try:
            return int(environ.get('LINES')), int(environ.get('COLUMNS'))
        except TypeError:
            return None, None

def number_of_colors(self):
        """Return the number of colors the terminal supports.

        Common values are 0, 8, 16, 88, and 256.

        Though the underlying capability returns -1 when there is no color
        support, we return 0. This lets you test more Pythonically::

            if term.number_of_colors:
                ...

        We also return 0 if the terminal won't tell us how many colors it
        supports, which I think is rare.

        """
        # This is actually the only remotely useful numeric capability. We
        # don't name it after the underlying capability, because we deviate
        # slightly from its behavior, and we might someday wish to give direct
        # access to it.
        colors = tigetnum('colors')  # Returns -1 if no color support, -2 if no
                                     # such cap.
        #  self.__dict__['colors'] = ret  # Cache it. It's not changing.
                                          # (Doesn't work.)
        return colors if colors >= 0 else 0

def supported(cls, stream=sys.stdout):
        """A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except Exception:
                # guess false in case of error
                return False

def supported(cls, stream=sys.stdout):
        """is platform supported

        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """

        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except Exception:
                # guess false in case of error
                return False

def enable_pretty_logging(logger, level='info', queue=None):
    """Turns on formatted logging output as configured.
    """
    logger.setLevel(getattr(logging, level.upper()))

    if not logger.handlers:
        # Set up color if we are in a tty and curses is installed
        color = False
        if curses and sys.stderr.isatty():
            try:
                curses.setupterm()
                if curses.tigetnum("colors") > 0:
                    color = True
            except:
                pass
        channel = logging.StreamHandler()
        channel.setFormatter(_LogFormatter(color=color))
        logger.addHandler(channel)
        if queue:
            queue_handler = QueueHandler(queue)
            queue_handler.setFormatter(_LogFormatter(color=color))
            logger.addHandler(queue_handler)

def _height_and_width(self):
        """Return a tuple of (terminal height, terminal width).

        Start by trying TIOCGWINSZ (Terminal I/O-Control: Get Window Size),
        falling back to environment variables (LINES, COLUMNS), and returning
        (None, None) if those are unavailable or invalid.

        """
        # tigetnum('lines') and tigetnum('cols') update only if we call
        # setupterm() again.
        for descriptor in self._init_descriptor, sys.__stdout__:
            try:
                return struct.unpack(
                        'hhhh', ioctl(descriptor, TIOCGWINSZ, '\000' * 8))[0:2]
            except IOError:
                # when the output stream or init descriptor is not a tty, such
                # as when when stdout is piped to another program, fe. tee(1),
                # these ioctls will raise IOError
                pass
        try:
            return int(environ.get('LINES')), int(environ.get('COLUMNS'))
        except TypeError:
            return None, None

def number_of_colors(self):
        """Return the number of colors the terminal supports.

        Common values are 0, 8, 16, 88, and 256.

        Though the underlying capability returns -1 when there is no color
        support, we return 0. This lets you test more Pythonically::

            if term.number_of_colors:
                ...

        We also return 0 if the terminal won't tell us how many colors it
        supports, which I think is rare.

        """
        # This is actually the only remotely useful numeric capability. We
        # don't name it after the underlying capability, because we deviate
        # slightly from its behavior, and we might someday wish to give direct
        # access to it.
        colors = tigetnum('colors')  # Returns -1 if no color support, -2 if no
                                     # such cap.
        #  self.__dict__['colors'] = ret  # Cache it. It's not changing.
                                          # (Doesn't work.)
        return colors if colors >= 0 else 0

def supported(cls, stream=sys.stdout):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except:
                # guess false in case of error
                return False

def number_of_colors(self):
        """
        Read-only property: number of colors supported by terminal.

        Common values are 0, 8, 16, 88, and 256.

        Most commonly, this may be used to test whether the terminal supports
        colors. Though the underlying capability returns -1 when there is no
        color support, we return 0. This lets you test more Pythonically::

            if term.number_of_colors:
                ...
        """
        # This is actually the only remotely useful numeric capability. We
        # don't name it after the underlying capability, because we deviate
        # slightly from its behavior, and we might someday wish to give direct
        # access to it.

        # trim value to 0, as tigetnum('colors') returns -1 if no support,
        # and -2 if no such capability.
        return max(0, self.does_styling and curses.tigetnum('colors') or -1)

def enable_pretty_logging(logger, level='info'):
    """Turns on formatted logging output as configured.
    """
    logger.setLevel(getattr(logging, level.upper()))

    if not logger.handlers:
        # Set up color if we are in a tty and curses is installed
        color = False
        if curses and sys.stderr.isatty():
            try:
                curses.setupterm()
                if curses.tigetnum("colors") > 0:
                    color = True
            except:
                pass
        channel = logging.StreamHandler()
        channel.setFormatter(_LogFormatter(color=color))
        logger.addHandler(channel)

def __has_colors(stream, allow_piping=False):
    """Check if Console Has Color."""
    if not hasattr(stream, "isatty"):
        return False
    if not stream.isatty():   # not being piped or redirected
        return allow_piping  # auto color only on TTYs
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        # guess false in case of error
        return False


# Has Color Init

def supported(cls, stream=sys.stdout):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except:
                # guess false in case of error
                return False

def supported(cls, stream=sys.stdout):
        """
        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except Exception:
                # guess false in case of error
                return False

def supported(cls, stream=sys.stdout):
        """Check the current platform supports coloring terminal output

        A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except Exception:
                # guess false in case of error
                return False

def supported(cls, stream=sys.stdout):
        """A class method that returns True if the current platform supports
        coloring terminal output using this method. Returns False otherwise.
        """
        if not stream.isatty():
            return False  # auto color only on TTYs
        try:
            import curses
        except ImportError:
            return False
        else:
            try:
                try:
                    return curses.tigetnum("colors") > 2
                except curses.error:
                    curses.setupterm()
                    return curses.tigetnum("colors") > 2
            except Exception:
                # guess false in case of error
                return False

def _height_and_width(self):
        """Return a tuple of (terminal height, terminal width).

        Start by trying TIOCGWINSZ (Terminal I/O-Control: Get Window Size),
        falling back to environment variables (LINES, COLUMNS), and returning
        (None, None) if those are unavailable or invalid.

        """
        # tigetnum('lines') and tigetnum('cols') update only if we call
        # setupterm() again.
        for descriptor in self._init_descriptor, sys.__stdout__:
            try:
                return struct.unpack(
                    'hhhh', ioctl(descriptor, TIOCGWINSZ, '\000' * 8))[0:2]
            except IOError:
                # when the output stream or init descriptor is not a tty, such
                # as when when stdout is piped to another program, fe. tee(1),
                # these ioctls will raise IOError
                pass
        try:
            return int(environ.get('LINES')), int(environ.get('COLUMNS'))
        except TypeError:
            return None, None

def number_of_colors(self):
        """Return the number of colors the terminal supports.

        Common values are 0, 8, 16, 88, and 256.

        Though the underlying capability returns -1 when there is no color
        support, we return 0. This lets you test more Pythonically::

            if term.number_of_colors:
                ...

        We also return 0 if the terminal won't tell us how many colors it
        supports, which I think is rare.

        """
        # This is actually the only remotely useful numeric capability. We
        # don't name it after the underlying capability, because we deviate
        # slightly from its behavior, and we might someday wish to give direct
        # access to it.
        colors = tigetnum('colors')  # Returns -1 if no color support, -2 if no
        # such cap.
        #  self.__dict__['colors'] = ret  # Cache it. It's not changing.
        # (Doesn't work.)
        return colors if colors >= 0 else 0

def __init__(self, term_stream=sys.stdout):
        """
        Create a `TerminalController` and initialize its attributes
        with appropriate values for the current terminal.
        `term_stream` is the stream that will be used for terminal
        output; if this stream is not a tty, then the terminal is
        assumed to be a dumb terminal (i.e., have no capabilities).
        """
        # Curses isn't available on all platforms
        try: import curses
        except: return

        # If the stream isn't a tty, then assume it has no capabilities.
        if not term_stream.isatty(): return

        # Check the terminal type.  If we fail, then assume that the
        # terminal has no capabilities.
        try: curses.setupterm()
        except: return

        # Look up numeric capabilities.
        self.COLS = curses.tigetnum('cols')
        self.LINES = curses.tigetnum('lines')

        # Look up string capabilities.
        for capability in self._STRING_CAPABILITIES:
            (attrib, cap_name) = capability.split('=')
            setattr(self, attrib, self._tigetstr(cap_name) or '')

        # Colors
        set_fg = self._tigetstr('setf')
        if set_fg:
            for i,color in zip(range(len(self._COLORS)), self._COLORS):
                setattr(self, color, curses.tparm(set_fg, i) or '')
        set_bg = self._tigetstr('setb')
        if set_bg:
            for i,color in zip(range(len(self._COLORS)), self._COLORS):
                setattr(self, 'BG_'+color, curses.tparm(set_bg, i) or '')

def has_colours(stream):
    if not hasattr(stream, "isatty"):
        return False
    if not stream.isatty():
        return False # auto color only on TTYs
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        return False

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def terminal_has_colors():
    if sys.platform=='cygwin' and 'USE_COLOR' not in os.environ:
        # Avoid importing curses that causes illegal operation
        # with a message:
        #  PYTHON2 caused an invalid page fault in
        #  module CYGNURSES7.DLL as 015f:18bbfc28
        # Details: Python 2.3.3 [GCC 3.3.1 (cygming special)]
        #          ssh to Win32 machine from debian
        #          curses.version is 2.2
        #          CYGWIN_98-4.10, release 1.5.7(0.109/3/2))
        return 0
    if hasattr(sys.stdout, 'isatty') and sys.stdout.isatty():
        try:
            import curses
            curses.setupterm()
            if (curses.tigetnum("colors") >= 0
                and curses.tigetnum("pairs") >= 0
                and ((curses.tigetstr("setf") is not None
                      and curses.tigetstr("setb") is not None)
                     or (curses.tigetstr("setaf") is not None
                         and curses.tigetstr("setab") is not None)
                     or curses.tigetstr("scp") is not None)):
                return 1
        except Exception:
            pass
    return 0

def has_colours(stream):
    if not hasattr(stream, "isatty"):
        return False
    if not stream.isatty():
        return False # auto color only on TTYs
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        # guess false in case of error
        return False

def has_colours(stream):
    if not (hasattr(stream, "isatty") and stream.isatty()):
        return False
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        # TODO: log console
        return False

def terminal_width(self):
        """Return the terminal width if possible, otherwise return 0.
        """
        ncols = 0
        try:
            import curses
            import io
            try:
                curses.setupterm()
                ncols = curses.tigetnum('cols')
            except AttributeError:
                # windows curses doesn't implement setupterm or tigetnum
                # code below from
                # http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/440694
                from ctypes import windll, create_string_buffer
                # stdin handle is -10
                # stdout handle is -11
                # stderr handle is -12
                h = windll.kernel32.GetStdHandle(-12)
                csbi = create_string_buffer(22)
                res = windll.kernel32.GetConsoleScreenBufferInfo(h, csbi)
                if res:
                    import struct
                    (bufx, bufy, curx, cury, wattr,
                     left, top, right, bottom, maxx, maxy) = struct.unpack("hhhhHhhhhhh", csbi.raw)
                    ncols = right - left + 1
            except curses.error:
                pass
            except io.UnsupportedOperation:
                pass
        except (ImportError, TypeError):
            pass
        return ncols

def terminal_has_colors():
    if sys.platform=='cygwin' and 'USE_COLOR' not in os.environ:
        # Avoid importing curses that causes illegal operation
        # with a message:
        #  PYTHON2 caused an invalid page fault in
        #  module CYGNURSES7.DLL as 015f:18bbfc28
        # Details: Python 2.3.3 [GCC 3.3.1 (cygming special)]
        #          ssh to Win32 machine from debian
        #          curses.version is 2.2
        #          CYGWIN_98-4.10, release 1.5.7(0.109/3/2))
        return 0
    if hasattr(sys.stdout, 'isatty') and sys.stdout.isatty():
        try:
            import curses
            curses.setupterm()
            if (curses.tigetnum("colors") >= 0
                and curses.tigetnum("pairs") >= 0
                and ((curses.tigetstr("setf") is not None
                      and curses.tigetstr("setb") is not None)
                     or (curses.tigetstr("setaf") is not None
                         and curses.tigetstr("setab") is not None)
                     or curses.tigetstr("scp") is not None)):
                return 1
        except Exception:
            pass
    return 0

def get(cap, *args, **kwargs):
    default = kwargs.pop('default', '')

    if 'PWNLIB_NOTERM' in os.environ:
        return ''

    if kwargs != {}:
        raise TypeError("get(): No such argument %r" % kwargs.popitem()[0])

    if cache == None:
        init()
    s = cache.get(cap)
    if not s:
        s = curses.tigetstr(cap)
        if s == None:
            s = curses.tigetnum(cap)
            if s == -2:
                s = curses.tigetflag(cap)
                if s == -1:
                    # default to empty string so tparm doesn't fail
                    s = ''
                else:
                    s = bool(s)
        cache[cap] = s
    # if `s' is not set `curses.tparm' will throw an error if given arguments
    if args and s:
        return curses.tparm(s, *args)
    else:
        return s

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _verbose(self, message):
        BLACK, RED, GREEN, YELLOW, BLUE, MAGENTA, CYAN, WHITE = range(8)

        # following from Python cookbook, #475186
        def has_colours(stream):
            if not hasattr(stream, "isatty"):
                return False
            if not stream.isatty():
                return False  # auto color only on TTYs
            try:
                import curses
                curses.setupterm()
                return curses.tigetnum("colors") > 2
            except:
                # guess false in case of error
                return False

        has_colours = has_colours(sys.stdout)

        def printout(text, colour=WHITE):
            if has_colours:
                seq = "\x1b[1;%dm" % (30 + colour) + text + "\x1b[0m\n"
                sys.stdout.write(seq)
            else:
                sys.stdout.write(text)

        if self.verboseMode:
            printout("hive-python: " + message, BLUE)

def has_colors(stream):
    '''Returns boolean indicating whether or not the supplied stream supports
    ANSI color.
    '''
    if not hasattr(stream, "isatty"):
        return False
    if not stream.isatty():
        return False # auto color only on TTYs
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        # guess false in case of error
        return False

def enable_pretty_logging():
    """Turns on formatted logging output as configured.

    This is called automatically by `parse_command_line`.
    """
    root_logger = logging.getLogger()
    if options.log_file_prefix:
        channel = logging.handlers.RotatingFileHandler(
            filename=options.log_file_prefix,
            maxBytes=options.log_file_max_size,
            backupCount=options.log_file_num_backups)
        channel.setFormatter(_LogFormatter(color=False))
        root_logger.addHandler(channel)

    if (options.log_to_stderr or
        (options.log_to_stderr is None and not root_logger.handlers)):
        # Set up color if we are in a tty and curses is installed
        color = False
        if curses and sys.stderr.isatty():
            try:
                curses.setupterm()
                if curses.tigetnum("colors") > 0:
                    color = True
            except Exception:
                pass
        channel = logging.StreamHandler()
        channel.setFormatter(_LogFormatter(color=color))
        root_logger.addHandler(channel)

def has_colours(stream):
    if not hasattr(stream, "isatty"):
        return False
    if not stream.isatty():
        return False # auto color only on TTYs
    try:
        import curses
        curses.setupterm()
        return curses.tigetnum("colors") > 2
    except:
        # guess false in case of error
        return False

def terminal_has_colors():
    if sys.platform=='cygwin' and 'USE_COLOR' not in os.environ:
        # Avoid importing curses that causes illegal operation
        # with a message:
        #  PYTHON2 caused an invalid page fault in
        #  module CYGNURSES7.DLL as 015f:18bbfc28
        # Details: Python 2.3.3 [GCC 3.3.1 (cygming special)]
        #          ssh to Win32 machine from debian
        #          curses.version is 2.2
        #          CYGWIN_98-4.10, release 1.5.7(0.109/3/2))
        return 0
    if hasattr(sys.stdout, 'isatty') and sys.stdout.isatty():
        try:
            import curses
            curses.setupterm()
            if (curses.tigetnum("colors") >= 0
                and curses.tigetnum("pairs") >= 0
                and ((curses.tigetstr("setf") is not None
                      and curses.tigetstr("setb") is not None)
                     or (curses.tigetstr("setaf") is not None
                         and curses.tigetstr("setab") is not None)
                     or curses.tigetstr("scp") is not None)):
                return 1
        except Exception:
            pass
    return 0

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def _stderr_supports_color():
    color = False
    if curses and hasattr(sys.stderr, 'isatty') and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color

def terminal_has_colors():
    if sys.platform=='cygwin' and 'USE_COLOR' not in os.environ:
        # Avoid importing curses that causes illegal operation
        # with a message:
        #  PYTHON2 caused an invalid page fault in
        #  module CYGNURSES7.DLL as 015f:18bbfc28
        # Details: Python 2.3.3 [GCC 3.3.1 (cygming special)]
        #          ssh to Win32 machine from debian
        #          curses.version is 2.2
        #          CYGWIN_98-4.10, release 1.5.7(0.109/3/2))
        return 0
    if hasattr(sys.stdout, 'isatty') and sys.stdout.isatty():
        try:
            import curses
            curses.setupterm()
            if (curses.tigetnum("colors") >= 0
                and curses.tigetnum("pairs") >= 0
                and ((curses.tigetstr("setf") is not None
                      and curses.tigetstr("setb") is not None)
                     or (curses.tigetstr("setaf") is not None
                         and curses.tigetstr("setab") is not None)
                     or curses.tigetstr("scp") is not None)):
                return 1
        except Exception:
            pass
    return 0

def enable_pretty_logging():
    """Turns on formatted logging output as configured.

    This is called automatically by `parse_command_line`.
    """
    root_logger = logging.getLogger()
    if options.log_file_prefix:
        channel = logging.handlers.RotatingFileHandler(
            filename=options.log_file_prefix,
            maxBytes=options.log_file_max_size,
            backupCount=options.log_file_num_backups)
        channel.setFormatter(_LogFormatter(color=False))
        root_logger.addHandler(channel)

    if (options.log_to_stderr or
        (options.log_to_stderr is None and not root_logger.handlers)):
        # Set up color if we are in a tty and curses is installed
        color = False
        if curses and sys.stderr.isatty():
            try:
                curses.setupterm()
                if curses.tigetnum("colors") > 0:
                    color = True
            except Exception:
                pass
        channel = logging.StreamHandler()
        channel.setFormatter(_LogFormatter(color=color))
        root_logger.addHandler(channel)

def select_mod(
    choices: Sequence[Mod],
    header: Optional[str] = None,
    footer: Optional[str] = None,
) -> Optional[Mod]:
    """Present user with a TUI menu and return his choice.

    Keyword arguments:
        choices: The :class:`Mod`s to choose from.
        header: Optional menu heading.
        footer: Optional menu footing.

    Returns:
        The selected mod.
    """

    menu = ModMenu(choices)

    head = urwid.Text(('title', header), align='center') if header else None
    foot = urwid.Text(('description', footer), align='center') if footer else None  # noqa: E501

    if head or foot:
        top = urwid.Frame(menu, head, foot)
    else:
        top = menu

    try:
        colors = curses.tigetnum('colors')
    except curses.error:  # Uninitialized terminal
        colors = 16

    event_loop = urwid.MainLoop(
        top,
        palette=ModMenu.palette,
        unhandled_input=exit_loop_on_q_esc,
    )
    event_loop.screen.set_terminal_properties(colors=colors)
    event_loop.run()

    return menu.chosen

def _stderr_supports_color():
    color = False
    if curses and sys.stderr.isatty():
        try:
            curses.setupterm()
            if curses.tigetnum("colors") > 0:
                color = True
        except Exception:
            pass
    return color