[Python-Dev] PEP 324: popen5 - New POSIX process module

Peter Åstrand peter at cendio.se
Wed Jan 7 12:31:59 EST 2004

> > Well, as I described in another mail, it's actually a big advantage to 
> > provide both a returncode attribute and an unmodified status value, since 
> > it's makes it easy to migrate from the "old" API. Perhaps we'll need to 
> > make some changes to the poll() method wrt Windows, though. 
> The peculiar "combined" nature of a Unix status value has no analogue in
> Windows. And in the context of an object with multiple attributes, I don't
> see the need anyway. I'd suggest
>     Popen.returncode - Process return code, valid on both Unix and Windows
>     Popen.signal - Signal which caused the program to exit, Unix only.

With .returncode being None, if the process died due to a signal? Looks 
good to me. 

> Code which is meant to be portable (to whatever extent that is possible) can
> use returncode without any problems. Code which is Unix-specific can worry
> about signal. (I'd suggest signal=0 means no signal occurred, and on Windows,
> signal is always 0. This means that it's still possible to write portable code
> which tests signal.)

Why not signal=None, if no signal occured? 


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