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Re: libiberty/pex-unix vfork abuse?
Daniel Jacobowitz <drow@false.org> writes:
> On Mon, Dec 10, 2007 at 11:18:57AM -0800, Joe Buck wrote:
>> While the standard's wording might need fixing, with every implementation
>> of vfork I know of, there are no threads. It's a mechanism for systems
>> that don't support fork (or that can only do fork in a horribly
>> inefficient way, say because there's no MMU, and no support for copy on
>> write), but that support the creation of new processes.
>
> No, Dave's right. On GNU/Linux you can have two threads running on
> different processors simultaneously calling vfork. And even with an
> MMU it is considerably more efficient than requiring setup of a new
> copy-on-write page table.
Glibc will map vfork to fork in a multithreaded environment.
Andreas.
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Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
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