subprocess returncode is masked

[Steve Holden]

Emmanuel wrote:
> MRAB wrote :
>> Emmanuel wrote:
>>> I'm using Python 2.6 and the new subprocess module to get the exit
>>> value of an external executable. It appears the return value given by
>>>  wait() or poll() operations is masked under Unix: I only get the
>>> lower 8 bits. So an exit value of 0x0402 in the C program will be
>>> seen as 0x02 in Python. And this does not happen on Windows... Any
>>> idea why that is ?
>>>
>> I believe that in Unix the exit code is indeed limited to 8 bits.
> Looks like you're right but the info is difficult to find since it is
> implementation dependent. I finally found it on
> http://en.wikipedia.org/wiki/Exit_status. This is very confusing because
> the parameter type of the exit function is an int ?!

Yes, but the parameter type is a superset of the function's domain.
That's not so unusual - consider math.sqrt(), for example. Its parameter
type is float, but what happens when you call math.float(-3.5)?

regards
 Steve
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