Neither get_select_fd() nor non-blocking

> 
> there are plenty of front-ends for which non-blocking
mode is not required
> (think command line, or cgi script, etc). all of my
front-ends work this way.

You might need non-blocking with command line or cgi scripts
as well. 
Nowadays, users expects "AJAX-typ" pages, that can
load incrementally. The 
old style "read everything, write everything" is
not fun, not even with 
CGI scripts.


> if each backend (there are 68+ of them) has both a
blocking and a non-blocking
> mode, that is quite a bit of code. 

Is it, really? I haven't written a backend myself, but from
the source, 
it's not obvious that "quite a bit of code" code
be removed by removing 
the non-blocking support. 


> it is also significantly more difficult to debug the
backend when it is 
> multi-threaded. given that many of our backends are
rarely touched or 
> are maintained by someone other than the original
author, it makes sense 
> to keep them simple.

I agree, I want to make it simple, both for the backend and
application 
developers. The problem with the current situation is:

1) Backend writers "needs" to support non-blocking
and get_select_fd, 
   since the documentation says they should, and some
applications might 
   require it.

2) Application developers needs to support backends which
cannot do 
   non-blocking or get_select_fd, and must therefore use
threading/forking 
   themself. 

This seems like a lose-lose situation: Both the backend and
frontend 
developers needs to handle all three cases. Well, the
frontend developers 
could skip to try non-blocking and get_select_fd and
*always* thread/fork 
themselves. But that would mean that the
non-blocking/get_select_fd code 
in the backends are useless. So one idea is to simply make
non-blocking 
sane_read and get_select_fd deprecated, and eventually
remove them...


> besides, its easier for app developer (who likely has
multi-threading in his
> app already for other purposes) to decide that he needs
it, and deal with the
> threading himself.

Personally, I think the select loop model is superior, but
since not all 
backends supports get_select_fd, an otherwise select based
application 
might be forced to start to fork/thread. Not pretty.


> the fujitsu backend no longer has threading for this
reason.

That means that you are not following the recommendations at

http://www.cendio.se
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