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Re: What to do about file:

From: Jason Robinson <JRobinson@KitchenPages.com>
Date: Fri, 20 Aug 2004 17:01:26 +1000
Message-ID: <00bf01c48683$83ab5ce0$16ffa8c0@kitchenpages.net>
To: "Larry Masinter" <LMM@acm.org>
Cc: <uri@w3.org>

In simple terms - I kind of liked that approach (ref: Larry).

I thought I would post this to the discussion because I agree with points
raised today in regards to a 'description' or 'result' for different users
or even some protocol standards used on various systems - however, I would
like to see a format where it is specific for different parts of each system
(or as needed) so more novice users like myself can view the result for each
'RFC' without guessing or running tests.  Eg: Inifiles.hpp for Win32,
richedit, etc...

Some parts of Windows9x systems like the INI file readers support legacy for
DOS and a kind of URI style (I am unsure of the authority - file or http)
file location.  The win INI <IniFiles.hpp> requires the full IP address as
it can not resolve DNS (it attempts to look for a logical drive) that can
then be followed by a path and file name.  eg:

PS: DOS and Windows based systems support the notion of a "drive letter".
I once did have a system which had double letters but I can not remember how
I did that as it was quite some time ago  (alowing for more then 26?) - so I
will mute this comment.

----- Original Message -----
From: "Larry Masinter" <LMM@acm.org>
To: "'Paul Hoffman / IMC'" <phoffman@imc.org>
Cc: <uri@w3.org>
Sent: Friday, August 20, 2004 4:13 PM
Subject: RE: What to do about file:

> Here's some text which might appear in a description of the
> 'file:' URI scheme. It's missing most of the important and
> interesting details; think of it as a proposal for organizing the
> material.  References to particular implementations are given
> by citing the implementation (or its documentation, if available),
> but the RFC explains the range of behavior for the areas
> where there are differences.
> What do you think of this approach?
> =====================================================
> - Hierarchical structure
> Most implementations of the 'file:' URI scheme do a reasonable
> job of mapping the hierarchical part of a directory structure
> into the '/' delimited hierarchy of the URI syntax, independent
> of what the 'native' platform delimiter is.
> For example, on Windows platforms, it is typical that the file
> system presents backslash '\' as the file delimeter for file
> names, yet the URI's forward slash '/' can be used in file: URIs.
> Similarly, on (some) Macintosh OS versions, at least in some
> contexts, the colon (':') is used as the delimiter in the native
> presentation of file path names.
> Unix systems natively use the same forward slash '/' delimiter
> for hierarchy, so there is a closer mapping between file paths
> and native path names.
> - 'Drives, drive letters, mount points, file system root'
> There is considerable difference, in practice, for handling
> of the syntax for the 'top' of the hierarchy.  The 'file:'
> URI syntax provides on simple place for designating the
> root of the file hierachy, and implementations have diverged,
> even on the same platform, sometimes even within a single
> application.
> For example, DOS and Windows based systems support the
> notion of a "drive letter", a single character which
> represents a (virtual) drive, mount point, or device.
> Native representations of file paths start with the drive letter,
> a colon, and then the path; e.g., "c:\tmp\test.txt".
> Drive letters can be mapped into the top of a 'file:' URI in various
> ways; some applications substitute horizontal bar "|" for
> the ":" after the drive letter, yielding   file:///c|/tmp/test.txt.
> In some cases, the : is left unchanged [a][b][d]; some applications
> omit it [f].
> UNC path names....
> Use of hostname, host name checking
> The 'file:' URI specification calls for using the actual
> host name as the name authority   file://myhostname/path
> and allowing it to be ommitted. This practice is rarely
> followed, and frequently is not checked.
> Omitting authority
> Some applications generate URIs with no authority component
> at all, e.g., file:/this/is/the/path  [x][y][z]
> Using native paths
> Some applications accept (and even generate) File URIs
> which use the native syntax instead of the canonical
> /-delimited one. [p][d][q].
> Character sets and encodings
> Local file systems of course may use many different encodings
> for representing file names. For interoperability sake, it would
> be preferable for file: URI libraries to translate the native
> character encoding for file names to and from Unicode, using
> URI /
> References
> [lwp-perl]  LWP perl library
> [java-net]  Java.net.URI
> [ms-net-lib]  Microsoft .NET library
Received on Friday, 20 August 2004 06:57:11 UTC

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