Cels Forum

Hello,
I think it's more a technical problem : to make it
short, there is 3 ways of checking if a page was update
or not : ETag (a kind of unique ID for a page generated
by the server), Last-modification date (the date returned
by the server based on the time on the files) and
checking the content of the page with a previous version.

The first 2 methods are by far the best as you don't
need to download the page. But not all servers can
handle it and many that do are not correct. Else,
when pages are generated by a database, those values
are meaningless. For such server/site, I have to use
the last method : downloading the page and checking
it with a previous copy. But it has it's own problem
mostly linked with bad network lines. Network programing
is pretty complex but I try to improve the program
when I can :)

And naturaly, the program doesn't care that a page
was changed to annonce new cels or to make any another
modification... which sometime result in false result.
(not all site have a update/news page.

Finaly, if I notice that someone is abusing, I will
remove it from Keep Track...

Cheers,
Yann stettler