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From: Chris McGee <newton688@gmail.com>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: [9fans] fd and /srv filesystem
Date: Wed, 4 Oct 2023 06:29:12 -0400	[thread overview]
Message-ID: <CAOk9ws3XmDacBCrsJajY1S3GumOPEM48gwQnkxg+1FD-Etwf=Q@mail.gmail.com> (raw)

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Hi All,

I was thinking about file descriptors in the context of Plan 9. On Unix an
fd is generally only usable by the current process, and child ones through
a fork with some special incantation if one wants to communicate one over a
domain socket. This is possibly for security reasons, avoiding other users'
processes from trying to guess the fd of a critical file.

It's common practice in Plan 9 to post an fd (sometimes via a pipe) from
one process to the /srv filesystem so that others can discover it and open
a comms channel. Does the kernel transform the fd into something when
posted to /srv so that it can be consumed by any other process in the
system?

Thanks,
Chris

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             reply	other threads:[~2023-10-04 10:29 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-10-04 10:29 Chris McGee [this message]
2023-10-04 12:20 ` hiro
2023-10-04 12:25   ` hiro
2023-10-04 16:06 ` ori
2023-10-04 23:42   ` Chris McGee

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