Proposal: overhaul System.Process

Duncan Coutts duncan.coutts at
Fri May 23 15:22:56 EDT 2008

On Fri, 2008-05-16 at 15:44 +0100, Brian Brunswick wrote:
> On Thu, May 15, 2008 at 10:45 AM, Simon Marlow <marlowsd at> wrote:
> > The latest version of the Process overhaul is here:
> >
> >
> >  - changes to readProcess, and added readProcessWithExitCode,
> >    as discussed on the list.
> >
> I'd just like to argue briefly again against merging stdout and stderr.

I think I agree. A more sensible default would be to discard stdout
completely or to use the inherited stderr. Though exactly which depends
on the context unfortunately.

For Cabal we have a function like readProcess and it discards stderr.
This seems to be the right thing for the various uses in Cabal (except
stupid "python -V" which prints the version number to stderr).


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