Re: Proposal: overhaul System.Process

Duncan Coutts wrote:

On Fri, 2008-05-16 at 15:44 +0100, Brian Brunswick wrote:

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On Thu, May 15, 2008 at 10:45 AM, Simon Marlow wrote:

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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).

Neil Mitchell and David Roundy argued against separating stdout and stderr for readProcessWithExitCode. Myself I don't have a strong opinion - although I'm somewhat swayed by Brian's points. It does seem slightly cleaner to separate the two in the default API. Any more opinions? Cheers, Simon