Version 4 of Tclhttpd Problems with Mozilla Keep-Alive

MHo, 2007-10-23

Here are some observations I made while I restarted an old project: porting an old tclhttpd 3.4.x-site to the latest incarnations of that webserver, 3.5.1 or 3.5.2.

I use my old build of that webserver, see Tclhttpd Winservice for further information.

The problem

I noticed that if I did not specify the file extension with an URL (like .htm or .tml), sometimes excessive delays occur. The resulting page appears in the browser, if ever, only after a very long delay period. Though I discover part of the program flow and learned that such page requests are satisfied via an error which was further handled by url_rewind and so on, I couldn't find any error.

But there are two facts:

This error didn't occur with 3.4x-versions of the webserver.
The logic has been largely rewritten between 3.4x and 3.5x (the monolythic doc.tcl splits up to doc.tcl, fallback.tcl., etc.).

Today, I found out that under the absolutely same circumstances my whole tests run fine with Opera. (I also tested IE7 but it failed for other reasions, as usual....). So I inspect my SeaMonkey settings once more. Just for a last test I disabled the Keep-Alive Option in the Http-Connection-Settings Page (stated as experimental), and: that did the trick!!!

Conclusion

There must be some subtle fact that leads to odd timeout/delay problems if a page was generated through url_unwind.

Unfortunately, my understanding of the code isn't good enough to track this problem further down. And, I fear, the whole tclhttpd isn't really maintained any more....