Default value for numCapabilities?

Johan Tibell johan.tibell at
Wed Apr 28 03:29:59 EDT 2010

On Wed, Apr 28, 2010 at 8:02 AM, Bryan O'Sullivan <bos at> wrote:
> On Tue, Apr 27, 2010 at 7:02 PM, Dimitry Golubovsky <golubovsky at>
> wrote:
>> This is probably about forkProcess rather than forkIO/forkOS, but why
>> this limitation?
> That's a standard Unix limitation. A child process is forked with one
> thread, so if the parent has multiple threads running, it's overwhelmingly
> likely that the child will be unable to execute correctly.

One problem used to be that the I/O manager would get killed but Simon
Marlow fixed that. I think we should support forking, with some
caveats, so that we can daemonize processes.

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