[nSLUG] Re: Idea For a New Site

Mike Spencer mspencer at tallships.ca
Thu Apr 24 23:23:30 ADT 2008


Dop wrote:

> Use their RSS feed.
> http://feeds.feedburner.com/DilbertDailyStrip

Um, what's an RSS feed?  Tikki-tikki..google..click..wikipedia...plok...

Oh. Hm.  I don't fully understand how this works so I guess we can
Remain On Topic If I ask how.

Here's how I get it:

   + You give a URL (or a collection of them) to a web feed-enabled
     browser or dedicated feed reader program.

   + The browser/program runs all the time, possibly in the
     background.

   + The program fetches specially formatted XML files offered by the
     feed servers referenced by the URLs and parses them.

   + The program then fetches documents referenced by the XML files.

   + In the XML (or in the HTTP headers or somewhere) for an
     individual document there is an expiry time.  For each XML feed
     file that the program is managing, it schedules and then performs
     a re-fetch of individual documents on or about their expiry
     times.

   + There is a bookmark-like mechanism to maintain state across
     reboots.

   + You terminate an individual "feed" by removing the URL for the
     relevant XML document from the list to be process by the
     browser/software. 


Is that how it works?

Does this mean that if I'm deep into reading something and a feed
time stamp expires, my browser will whap open a new window with the
latest update on $WHATEVER?

(The casual assertion on Wikipedia that a user "subscribes" to a
"feed" is as uninformative and misleading for a novice as the notion
of "subscribing" to a news group, when the entire "subscription"
process is just a matter of bookkeeping on localhost.)

Well, the HTML file handed out by the New and Improved Dilbert has
this new and desirable feature:  It's easy to parse out the URL for
the comic strip image.  So I wrote a Perl script for
localhost/cgi-bin that fetches the served file, parses out the image
URL and writes a new HTML doc with just that <IMG... tag in the body.
A link to the localhost script resides on my home page.

I works fine. Of course they'll change something by 'n bye and it will
stop working.  Maybe not soon. :-)

ObLinux: The foregoing isn't off topic. The ability to do the trick
with localhost CGI scripts is definitely a Linux asset. I do the same
with the Empire Theatre site so that I get just a tidy list of movie
names and screen times for the local theatre and elide all the
promotional crap.


- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^



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