RE: [boost] Re: boost::filesystem file restrictions

From: Glen Knowles (gknowles_at_[hidden])
Date: 2003-08-15 12:42:27

From: David Abrahams [mailto:dave_at_[hidden]]

>Yes, an absolute URI identifies a single location in the virtual name
>tree.  The only way to make this like a current-drive-relative path is
>to consider processes which are moved, *during execution*, across a
>network of computers.  I've never heard of systems which do that that,
>but even if they exist I don't think they make an appropriate model on
>which to define the notion of "absolute path" in a filesystem library.

The point, and this is the only one that truly compells me, is that:
http://localhost/blah and /blah are absolute URL paths. c:/blah is an
absolute filepath and, to be consistent, /blah should be too. If you look at
a drive as equivalent to a URL authority they map very well. You can try to
argue that an authority such as "localhost" uniquely identifies a computer,
but that really isn't true. It is normal for mail....com, www....com, etc to
all refer to the same computer, a computer used for webhosting may have
thousands of such authorities.

>> If you can give me an example of a multirooted system that refers to
>> paths that are absolute with respect to the current directory as
>                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>What does that mean?
>And what does it mean for a multirooted system to "refer to a path as
>relative?"  Do you mean in the official platform specification, or
>something else?

I was thinking of platform documentation, preferably an actual
"is_relative()" system function. I've subsequently found enough examples to
drop this as an argument.

One thing that I hope we can agree on is that, irrespective of what they're
called, we do need functions to distinguish between a:/foo, /foo, foo, and
possibly a:foo.

Glen