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Re: libiberty/pex-unix vfork abuse?
"Dave Korn" <dave.korn@artimi.com> writes:
> On 07 December 2007 20:52, Andreas Schwab wrote:
>
>> "Dave Korn" <dave.korn@artimi.com> writes:
>>
>>> Perhaps we could work around this case by setting environ in the parent
>>> before the vfork call and restoring it afterward, but we'd need kind of
>>> serialisation there,
>>
>> Do we? vfork should block the parent until the child calls execve or
>> exit.
>
> I don't see anything in posix that suggests that?
That is true, but technically it is rather difficult to implement a true
vfork without blocking the parent between vfork and exec/exit, since
that these are the only synchronisation points.
> I'm worrying in this case about races between multiple threads in the
> parent vfork'ing multiple children,
Typically in a multithreaded environment vfork is mapped to fork anyway.
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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