http and ranges
Daniel Hellerstein (danielh@MAILBOX.ECON.AG.GOV)
Fri, 18 Sep 1998 10:43:50 -0400
> Thanks. Now I see how to do a GET with range request.
> Now, another question:
> Is there a way to specify the offset or range with the http: URL
> syntax ?
> i.e. something like http://host/dir/file@range=0,500
The real question is how such an addition (to some future http 1.2)
would be used. I can think of two general cases:
1)Aas a means of obtaining a portion of a resource; such as a
single chapter of a long document.
But one could always just have separate files containing chapter 1,
chapter 2,.. ( as complements to the "entire document"). Alternatively, a
script (cgi-bin or whatever) that would parse the request line, looking
for a "@range", and (if found) use the "=0,500" to selectively return a
portion of the document, should be fairly easy to create.
2) As a means of selectively updating a portion of an otherwise large
resource. For example, acrobat can use a range: header to request
selected pages of a long pdf file.
But this then means having client software (i.e.; browsers) that
understand the request syntax being used. But there already is a
syntax that will support such actions (that is, the aforementioned use of
range: request header).
In other words, although new http methods, etc (such as adoption of a
RANGE method) might be useful, I suspect it's not worth the trouble.