From mboxrd@z Thu Jan  1 00:00:00 1970
From: jack@0x6a.com (Jack Norton)
Date: Wed, 23 Mar 2011 08:21:56 -0500
Subject: [9fans] namespaces, Alef
In-Reply-To: <9d5755de-60ad-4f53-87b4-b4b6d19f8858@o21g2000prh.googlegroups.com>
References: <9d5755de-60ad-4f53-87b4-b4b6d19f8858@o21g2000prh.googlegroups.com>
Message-ID: <4D89F3F4.4020604@0x6a.com>
Topicbox-Message-UUID: bf88aede-ead6-11e9-9d60-3106f5b1d025

faif wrote:
> Some questions that came up while reading the first paper (Plan 9 from
> Bell Labs):
> 
> a) It seems that the potential of namespaces can be exposed only when
> using a distributed environment with multiple machines (CPU servers,
> file servers, terminals, etc.). Can I get a feeling about what a
> namespace is in practice if I only own a single system installed on a
> virtual machine?
> 

You are forgetting about per-process namespaces.  For instance, when you 
run httpd, a custom namespace gets constructed that is unique to it. 
Typically '/usr/web' gets bound to / in the namespace of httpd (among 
other things).  Also certain things *don't* get bound too.  Why would 
httpd need to access eia0? Don't put it in the namespace.

The very point of all of this capability is that it is completely 
transparent to all things being on one machine, or on 20 machines.

> b) I know that Limbo is mostly used in Inferno, but is Alef or Limbo
> used in any parts of the native Plan 9? According to wikipedia (http://
> en.wikipedia.org/wiki/Alef_%28programming_language%29) the Alef parts
> were rewritten in C.
> 

I'm pretty sure there is no Alef left in the latest.  There is no Limbo 
either.  I could be wrong.


-Jack