The CERN libWWW code has _always_ cached ftp connections. Therefore, it
takes a conscious decision of a browser author to disable it. I know for
certain that at least: AIR Mosaic, Emacs-w3, LineMode Browser, Cello,
WinMosaic, OmniWeb, ad nauseum, all did this correctly. I think that for a
time Mosaic/X was broken in this regards, but am not 100% sure. Not sure
about MacWeb, WinWeb, or MacMosaic. I'm pretty sure that all the SpyGlass
mosaics have always worked correctly in this regard, but could not swear to
it.
> I think Netscape caches FTP connections, however. I can't otherwise
> explain the speed of succesive file retrieves from ftp servers and the
> output of netstat that shows ESTABLISHED connections long after I've left
> the server. Their downfall at one point seemed to be that they
> maintained ftp connections far too long, so that they were consuming
> valuable slots on heavily used ftp servers that restrict the number of
> connections.
This is a bit of a problem. Browsers should have a user-specifiable
timeout for each ftp connection.
> In short, if you're worried about serving FTP-based information to people
> with Web browsers you'll have to try and understand the mix of clients
> (traditional ftp programs vs. inefficient first generation Web browsers vs.
> more efficient tools like Netscape) to see which is the better protocol.
I'll argue against the 'inefficiency' of the first generation web
browsers. :)
-Bill P.