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From: Eric Blake <ebb9 AT byu DOT net>
Subject:  Re: Question of the necessity of rebaseall
Date: Thu, 14 May 2009 23:23:08 +0000 (UTC)
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Christopher Faylor <cgf-use-the-mailinglist-please <at> cygwin.com> writes:

We can't say it enough:

> >>Read the source.
> >Is this a place where using vfork() instead of fork() helps (where it's
> >applicable, of course)?  If so, we might be able to reduce the number
> >of rebase failures in the future just by trying to push other projects
> >to use vfork wherever it's substitutable for fork...
> 
> In Cygwin vfork == fork.

But, if you really wanted to be nice, instead of forcing us to respond to your 
uneducated guesses, you could implement posix_spawn, and push for more upstream 
projects (particularly bash) to use it.  That is at least one case where people 
have already implemented posix_spawn on top of fork (and in fact, gnulib has 
already done so, and m4 uses the gnulib implementation), but where you can also 
implement it more efficiently on top of native windows semantics if you do it 
right.  And maybe, in the process of seeing how many loose ends there are to 
get it to have posix_spawn work correctly, you will start to understand why we 
haven't already implemented it, and why cygwin does fork/vfork the way it does.

-- 
Eric Blake





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