From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: Date: Sat, 6 Dec 2008 05:52:59 -0500 From: "Dan Cross" To: "Fans of the OS Plan 9 from Bell Labs" <9fans@9fans.net> In-Reply-To: <9364844C-2046-4E9E-B007-40F770B9B8B0@sun.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <1aac8590e5d726419683d3f01a9d11f1@quanstro.net> <9364844C-2046-4E9E-B007-40F770B9B8B0@sun.com> Subject: Re: [9fans] How to implement a moral equivalent of automounter in Plan9? Topicbox-Message-UUID: 5be269da-ead4-11e9-9d60-3106f5b1d025 On Sat, Dec 6, 2008 at 12:24 AM, Roman Shaposhnik wrote: >> There are many things that would be *possible* with /proc, some of >> them ill advised. For instance, why can't I 'mkdir /proc/n/' and have >> it create a new process? > > There's an aswer to that given by Ken in the Plan 9 paper: > http://www.cs.bell-labs.com/sys/doc/9.html: > ----------------------------------------------------------------------------------------------------- > Nonetheless, it is possible to push the idea of file-based computing too > far. > Converting every resource in the system into a file system is a kind of > metaphor, > and metaphors can be abused. A good example of restraint is/proc, which is > only a view of a process, not a representation. To run processes, the usual > fork and exec calls are still necessary, rather than doing something like > cp /bin/date /proc/clone/mem > ------------------------------------------------------------------------------------------------------ My mention of that was a contrived example. But anyway.... This explains an artifact of the implementation, not the rationale behind it, other than that it was considered to be metaphor abuse, which everyone kind of "knows" but no one's really said *why* it's a bad thing. My argument, if you chose to pick through my convoluted wording, was that it drastically changed the process model, but it's unknown whether that's truly a bad thing (though most reasonable people would agree that it is). > P.S. I suppose one might argue that it is also an answer to *my* original > question -- /proc//ns is just a representation. Well, that's one answer but not a very satisfying one. I think my point was somewhat along Russ's lines; that no one's felt the need to explore it. - Dan C.