On Thu, 2007-08-16 at 15:06 +0100, Denys Vlasenko wrote:
> Hi people,
> 
> In handle_incoming_and_exit() we used to do this
> just before exit:
> 
>         /* Properly wait for remote to closed */
>         int retval;
>         shutdown(accepted_socket, SHUT_WR);
>         do {
>                 fd_set s_fd;
>                 struct timeval tv;
>                 FD_ZERO(&s_fd);
>                 FD_SET(accepted_socket, &s_fd);
>                 tv.tv_sec = 2;
>                 tv.tv_usec = 0;
>                 retval = select(accepted_socket + 1, &s_fd, NULL, NULL, &tv);
>         } while (retval > 0 && read(accepted_socket, iobuf, sizeof(iobuf) > 0));
                               Actually this looks like a bug ^^^^^^^^^^^^^^^^^
and the line should have been:
          } while (retval > 0 && read(accepted_socket, iobuf, sizeof(iobuf)) > 0);
>         shutdown(accepted_socket, SHUT_RD);
>         close(accepted_socket);
>         exit(0);
> 
> Apparently we first inform peer that we are not going to write anything
> anymore, and then we drain any remaining input.
> 
> Question - why is this needed? What bad things can happen if we just exit(0)
> without doing all this?

The "shutdown(accepted_socket, SHUT_RD)" and "close(accepted_socket)" is
superfluous since exit() closes all file descriptors anyway.

The exit() (or a close() instead of the "shutdown(accepted_socket,
SHUT_WR)") can produce an error on the sending side if there are byte
left in some buffer there.
And IE5/IE5.5 (I don't know about more recent IEs) delivered an
confusing and misleading (IIRC) error window, if that happens.

This was especially annoying (read: it happened pretty every time) since
several versions had a bug where IE sent 2 more bytes than actually told
the server in the HTTP request.

Perhaps the above can be reduced by simply having a blocking read() and
avoid the select():
----  snip  ----
    while (read(accepted_socket, iobuf, sizeof(iobuf)) > 0) {
         /* do nothing */;
    }
----  snip  ----

	Bernd
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