9fans - fans of the OS Plan 9 from Bell Labs
 help / color / mirror / Atom feed
* [9fans] fd and /srv filesystem
@ 2023-10-04 10:29 Chris McGee
  2023-10-04 12:20 ` hiro
  2023-10-04 16:06 ` ori
  0 siblings, 2 replies; 5+ messages in thread
From: Chris McGee @ 2023-10-04 10:29 UTC (permalink / raw)
  To: Fans of the OS Plan 9 from Bell Labs

[-- Attachment #1: Type: text/plain, Size: 925 bytes --]

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

------------------------------------------
9fans: 9fans
Permalink: https://9fans.topicbox.com/groups/9fans/Tfaa2554a9b74c479-M6b518cab901dcf6bf60bd280
Delivery options: https://9fans.topicbox.com/groups/9fans/subscription

[-- Attachment #2: Type: text/html, Size: 1476 bytes --]

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2023-10-04 23:43 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-10-04 10:29 [9fans] fd and /srv filesystem Chris McGee
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

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).