[9fans] create(2)/open(2) race for file creation

[Photon photon@dtmf.com]

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Would it not be possible to create a system call "atomic
test-and-create" called stat_crate() or something?  And let the system
use atomic test-and-set ipc mechanisms to make it atomic across other
calls to stat_create(), stat(), and create()?  Then the only question
would still be making this work with calls on different cpu servers,
right?  Maybe another 9P call to the fileserver would have to be created
to let the atomic-ness exist at the file server and not in the cpu
server's kernel?

Brandon

Rob Pike wrote:
> 
> If you're trying to create lock files dozens of times per second
> in a union directory you deserve whatever failures the system
> sees fit to provide.
> 
> -rob
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