Re: lynx-dev strange HTTP/HTCheckForInterrupt() bug

[Leonid Pauzner]

29-Mar-99 10:46 Klaus Weide wrote:
> On Mon, 29 Mar 1999, Leonid Pauzner wrote:

>> >> Apperantly, *sometimes* lynx got aborted with exit status
>> >> just after pressing 'z'. So I see
>> >>
>> >> Alert!: Unable to connect to remote host.
>> >> Exiting via interrupt: 15
>>[...]

>> Well, "Unable to connect to remote host" should be a too far consequence
>> since we interrupt the connection and trying to pop the previous document.

> I don't understand what you mean with 'too far consequence'.
Sorry my English...
I mean the question "unable to connect to which host?"
My guess lynx mean the previous document, but you trace show otherwise.
So the message misguiding - should be at least "interrupted by user".

>> The latter may be a problem when that document not cached

> Were you going back in history, or following a link when you pressed 'z'?
following link.

>> and we can't process a new HTTP connection since
>> something was messed from our original interrupt
>> (may be a timing problem so a short delay is necessary between the processes
>> or something was not flash()'ed in some sence. So a new child
>> is not completely independent from a previous one...)

> I don't think it is a delayed effect at that level - If I understand you 
> right,
> Lynx already acted on the 'z', and (if you pressed 'z' only once), I don't
> see how it can act on the 'z' again - it has already been eaten.
I cannot be sure, probably 'z' effectively sent twice,
it should be blocked.

> You seem to assume that "Alert!: Unable to connect to remote host." is from
> the request you interrupted with 'z', and "Exiting via interrupt: 15" is
No (see above).
> from the next request, right?  But I don't think that is the case; if it
> were so, there should have been some intermediate status messages
> ("Getting ...", "Making HTTP connection to ...").

>> Oh, shouldn't we override "no_cache" for a poped document
>> in any case when the next HText_new() even not started?

> I don't understand.  Where and why?
I don't understand either. After pressing 'z' lynx should be stopped
but apparenly it sent a new request over the net and trying to load something.
My guess was the previous document (probably not).

>   -----

> I get the following, very similar to yours, by starting

>      no_proxy='*' lynx -dump -tlog http://localhost -trace 2>&1|less

> and then paging through the output with less rather quickly.  It is
> repeatable.   I think I understand why the name lookup fails
> (of course it normally always works for "localhost").  Each keyboard
> input character shortens a select() in the NSL_FORK parent's loop,
> even those that have been typed before the lookup started (and
> enven though ther are not meant for lynx at all).  If there are enough
> of those keys pressed (as compared to dns_patience=30), the patience
> is exhausted before the child even has a chance to do a lookup for
> localhost.  Maybe even before the child gets a chance to
> execute signal(SIGTERM, quench), and that may be the reason why we
> see the child's 'Exiting via interrupt: 15' at all.  The child is
> killed by the parent's kill(fpid, SIGTERM) when the parent thinks
> it's time to give up.   Output from parent and child are intermixed.

> I still don't understand it completely.  And don't know exactly how this
> relates to your case.   Did you press many (at that time dead) other
> keys before or after the 'z'?


> --------------- output ---------------
> [.......]
> New anchor 0x81a8c38 has hash 95 and address `http://localhost/'
> HTAccess: loading document http://localhost/
> HTParse: aName:http://localhost/   relatedName:file:
> HTParse: result:http
> HTParse: aName:http://localhost/   relatedName:
> HTParse: result:localhost
> Looking up localhost.
> HTParseInet: parsing `localhost'.
> HTParseInet: Can't find internet node name `localhost'.
> Unable to locate remote host localhost.
> HTTP: Unable to connect to remote host for `http://localhost/' (errno = 10).

> Alert!: Unable to connect to remote host.



> Exiting via interrupt: 15

> HTAccess:  status=-29999
> HTAccess: `http://localhost/' has been accessed, No data loaded.

> lynx: Can't access startfile http://localhost/
> LYStoreCookies: save cookies to /home/lynxdev/.lynx_cookies on exit
> LYStoreCookies: 922715707 cf 2145801600 STORED
> --------------- end ---------------
> [ more LYStoreCookies, that's all ]