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From: "Alyssa M via 9fans" <9fans@9fans.net>
To: 9fans <9fans@9fans.net>
Subject: Re: [9fans] openat()
Date: Fri, 5 Apr 2024 17:49:43 -0400	[thread overview]
Message-ID: <17123537830.EbFe44.28920@composer.9fans.topicbox.com> (raw)
In-Reply-To: <CAP6exYLifv8_ujLxN4wEq+PQuJcDmM8zH9KwVh+czoZSMWDrXA@mail.gmail.com>

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Are you thinking narrowly about "What changes to the Plan 9 kernel would you make to emulate the Linux openat() system call" or more generally about "How would you design a facility for plan 9 that provides an equivalent service?

As I understand it from the rationale section on the linux man page, the call exists to avoid a race condition between checking that a directory exists and doing something to a path containing it. An additional motivator is providing the effect of additional current working directories notably for Linux threads (which presumably don't have their own. I think 'threads'  (processes that share memory) on Plan 9 do???).

This is all based on the assumption that holding a file/directory open keeps it alive and in existence... which on Plan 9, I think it doesn't, does it? As I understand it, remove can remove a file or directory that is open, which is not like UNIX/Linux...

Sorry, I'm just trying to understand the question.


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  parent reply	other threads:[~2024-04-05 21:49 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-04-05 19:50 ron minnich
2024-04-05 20:12 ` Gorka Guardiola
2024-04-05 20:15   ` Gorka Guardiola
2024-04-05 20:36     ` Gorka Guardiola
2024-04-05 21:22       ` ron minnich
2024-04-05 21:43         ` Bakul Shah via 9fans
2024-04-05 21:49         ` Alyssa M via 9fans [this message]
2024-04-05 22:29           ` Gorka Guardiola
2024-04-06  3:18             ` moody
2024-04-06 17:35               ` ron minnich
2024-04-06 19:23                 ` David Leimbach via 9fans
2024-04-06 19:54                 ` Bakul Shah via 9fans
2024-04-06 19:24               ` Alyssa M via 9fans
2024-04-06 20:51                 ` moody
2024-04-07  1:36                   ` Alyssa M via 9fans
2024-04-07 15:00                     ` Alyssa M via 9fans
2024-04-10 12:17                       ` wb.kloke

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