ANSI colored output: How to determine how python was called?

[David M. Cooke]

At some point, Pearu Peterson <pearu at cens.ioc.ee> wrote:

>> [Donn Cave]
>> 
>> > Quoth Pearu Peterson <pearu at cens.ioc.ee>:
>> 
>> > |   Are there alternative (hopefully better) ways to decide whether the
>> > |   output "device" of python stdout supports ANSI colored text or not?
>> 
>> The normal way to check for colour terminal support is through terminal
>> info capabilities (terminfo).  Check for `op', 'AF', `AB', `Sf', `Sb',
>> 'Co', `pa' and `NC' capabilities, in particular.  I forgot details as of
>> now, but remember I had to fight a bit to get everything right.
>
> Thanks for the hint.
>
> I now discovered the Python curses module. It seems that
>
>   sys.stdout.isatty() and curses.wrapper(lambda s:curses.has_colors())
>
> gives a reliable answer for if the terminal supports colors or not.
> However, when using it, the screen "blinks" (the terminal is blanked
> and then its contents is restored) as curses.wrapper(..) initializes and
> deinitializes the ncurses library. I have not found yet if this
> "blink" could be avoided.

I think what you want is something like:

def term_has_colours():
    if not sys.stdout.isatty():
       return 0
    curses.start_color()
    return curses.has_colors()

curses.wrapper does more than you need. I use something like the above
in my $PYTHONSTARTUP file to give me a coloured prompt.

-- 
|>|\/|<
/--------------------------------------------------------------------------\
|David M. Cooke
|cookedm(at)physics(dot)mcmaster(dot)ca