Date: Mon, 8 Jun 1998 21:29:13 -0400 From: Garance A Drosihn <drosih@rpi.edu> To: current@FreeBSD.ORG Subject: Re: Variant Link implementation (Was: Re: lorder problem: ....... ) Message-ID: <v04011705b1a23ef25ab4@[128.113.24.47]> In-Reply-To: <199806082025.NAA00919@dingo.cdrom.com> References: Your message of "Mon, 08 Jun 1998 16:05:35 EDT." <v04011704b1a1f25d596a@[128.113.24.47]>
next in thread | previous in thread | raw e-mail | index | archive | help
At 1:25 PM -0700 6/8/98, Mike Smith wrote:
>> Garance Drosihn wrote:
>> I have a question, given the subject of this thread. Are we talking
>> about something that is only available when processing links, or are
>> we talking about something that would be available for any pathname
>> reference?
>
> We're only talking about substitutions on the target field of symbolic
> links.
>
>> In AFS, I can reference /place/program/@sys/src, as long as /place
>> is in an AFS file system. ("@sys" is the literal string used to
>> indicate the afs-system-variable, and afs turns that into some
>> string such as "sun4x_55", depending on what platform you are on
>> when the variable is expanded).
>
> This would require parsing *every* path component. I don't think
> that the overheads involved in this would be popular at all.
For what it's worth, AFS only allows the variable name to be at the
start of a path component (and in fact I think the component has to
be nothing but a variable name). So, there isn't a lot of parsing
overhead for paths which do not reference a variable. Basically
it's just a "if ( *pathpart == '@' ) { process_variables() }".
I'm not saying that freebsd should necessarily do the same thing,
I just wanted to describe what AFS does minimize the overhead of
parsing...
---
Garance Alistair Drosehn = gad@eclipse.its.rpi.edu
Senior Systems Programmer or drosih@rpi.edu
Rensselaer Polytechnic Institute
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?v04011705b1a23ef25ab4>