Portable way to refer to the null device?

[nick at stinemates.org]

On Fri, Feb 06, 2009 at 07:32:20PM -0800, Roy Smith wrote:
> I need to run a command using subprocess.Popen() and have stdin
> connected to the null device.  On unix, I would do:
> 
>         self.process = subprocess.Popen(argv,
>                                         env=new_env,
>                                         stdout=open(outfile, 'w'),
>                                         stderr=open(errfile, 'w'),
>                                         stdin=open('/dev/null')
>                                         )
> 
> but that's not portable to windows.  Does Python have a portable way
> to get a file object connected to the null device, regardless of what
> operating system you're running on?

I normally just implement my own object:

class DevNull:
    def write(self, str):
        pass