wxhaskell-devel

[wxhaskell-devel] Application hangs when using processExecAsyncTimed

[Bernd H. <ber...@ic...>]

Hi all,

I use wxHaskell 0.10.3 on Windows (XP) for writing a GUI to manage and 
execute test cases. Sadly, when using processExecAsyncTimed, the whole 
application sometimes hangs because process termination seems not to be 
recognized reliably. This happens about every 4th or so try. I used 
processExecAsync before which works but is deprecated and slow (because 
we have a byte-wise stdout stream). Any idea whether this is a wxWidgets 
problem or is wxHaskell specific?

Thanks,
Bernd

Re: [wxhaskell-devel] Application hangs when using processExecAsyncTimed

[Eric Y. K. <eri...@gm...>]

Shelarcy: any ideas?

Bernd, it may be worth filing a bug report, and maybe submitting a test
case for our bugs directory (i.e. a darcs patch for wxhaskell).  If it
turns out to by a wxWidgets problem we can report it to them.

By the way, if anybody here proficient in C++ could volunteer to write
equivalent test cases in wxWidgets, it would a big help!

On Thu, May 08, 2008 at 13:10:12 +0200, Bernd Holzmüller wrote:
> I use wxHaskell 0.10.3 on Windows (XP) for writing a GUI to manage and 
> execute test cases. Sadly, when using processExecAsyncTimed, the whole 
> application sometimes hangs because process termination seems not to be 
> recognized reliably. This happens about every 4th or so try. I used 
> processExecAsync before which works but is deprecated and slow (because 
> we have a byte-wise stdout stream). Any idea whether this is a wxWidgets 
> problem or is wxHaskell specific?

-- 
Eric Kow <http://www.nltg.brighton.ac.uk/home/Eric.Kow>
PGP Key ID: 08AC04F9

Re: [wxhaskell-devel] Application hangs when using processExecAsyncTimed

[shelarcy <she...@gm...>]

Hi,
I'm sorry about my reply is late.

On Thu, 15 May 2008 17:15:54 +0900, Eric Y. Kow <eri...@gm...> wrote:
> Shelarcy: any ideas?

I found Mad's previous patch left an problem for Windows platform.

http://article.gmane.org/gmane.comp.lang.haskell.wxhaskell.general/423

Windows' stdout, stdin and stdout requires console. But we can build
wxHaskell GUI program without console by -optl-mwindows option. So,
withCharResult's "hPutStrLn stderr" causes problem. I fixed this problem
by using Debug.Trace.putTraceMsg instedad of hPutStrLn stderr.

http://www.haskell.org/ghc/docs/6.8.2/html/users_guide/terminal-interaction.html
http://www.haskell.org/ghc/docs/6.8.2/html/libraries/base/Debug-Trace.html#v%3AputTraceMsg

I will send patch soonly (with a few extention). But I don't know this
problem is a Brend's problem.

Best Regards,

> On Thu, May 08, 2008 at 13:10:12 +0200, Bernd Holzmüller wrote:
>> I use wxHaskell 0.10.3 on Windows (XP) for writing a GUI to manage and
>> execute test cases. Sadly, when using processExecAsyncTimed, the whole
>> application sometimes hangs because process termination seems not to be
>> recognized reliably. This happens about every 4th or so try. I used
>> processExecAsync before which works but is deprecated and slow (because
>> we have a byte-wise stdout stream). Any idea whether this is a wxWidgets
>> problem or is wxHaskell specific?

-- 
shelarcy <shelarcy    hotmail.co.jp>
http://page.freett.com/shelarcy/

Re: [wxhaskell-devel] Application hangs when using processExecAsyncTimed

[Mads L. <mad...@ya...>]

Hi,

shelarcy wrote:
> Hi,
> I'm sorry about my reply is late.
> 
> On Thu, 15 May 2008 17:15:54 +0900, Eric Y. Kow <eri...@gm...> wrote:
> > Shelarcy: any ideas?
> 
> I found Mad's previous patch left an problem for Windows platform.
> 
> http://article.gmane.org/gmane.comp.lang.haskell.wxhaskell.general/423
> 
> Windows' stdout, stdin and stdout requires console. But we can build
> wxHaskell GUI program without console by -optl-mwindows option. So,
> withCharResult's "hPutStrLn stderr" causes problem. I fixed this problem
> by using Debug.Trace.putTraceMsg instedad of hPutStrLn stderr.

Have you actually observed that this is problem in the specific case
with processExecAsyncTimed?

I am asking because if you have observed it at windows, then what I
thought was a Linux-only issue is also a Windows issue. After all, the
putStrLn only happens in case of an error (negative unicode).

Just to be clear, I am not arguing against the patch, I just want to
know if the processExecAsyncTimed problem also occurs on windows.


Greetings,

Mads

Re: [wxhaskell-devel] Application hangs when using processExecAsyncTimed

[shelarcy <she...@gm...>]

Hi Mads,

On Tue, 27 May 2008 04:00:31 +0900, Mads Lindstrøm <mad...@ya...> wrote:
> Have you actually observed that this is problem in the specific case
> with processExecAsyncTimed?
>
> I am asking because if you have observed it at windows, then what I
> thought was a Linux-only issue is also a Windows issue. After all, the
> putStrLn only happens in case of an error (negative unicode).

I can't reproduce that error in my environment with command (I don't
use Graphics.UI.WXCore.Process usually. So, I don't know which command
reproduces error). But I think this is not only Linux problem but also
all platform that use before wxWidgets 2.8.x.

Because wxWidgets Change Log writes following:

- wxInputStream::GetC() now returns an int in the range 0 - 255 on success
   instead of a char the range -128 - 127.

You can see this message in wxWidgets-*.*.*/docs/changes.txt.
Or below URL

http://slackblogs.blogspot.com/2006/12/wxwidgets-280.html


Best Regards,


> shelarcy wrote:
>> Hi,
>> I'm sorry about my reply is late.
>>
>> On Thu, 15 May 2008 17:15:54 +0900, Eric Y. Kow <eri...@gm...> wrote:
>> > Shelarcy: any ideas?
>>
>> I found Mad's previous patch left an problem for Windows platform.
>>
>> http://article.gmane.org/gmane.comp.lang.haskell.wxhaskell.general/423
>>
>> Windows' stdout, stdin and stdout requires console. But we can build
>> wxHaskell GUI program without console by -optl-mwindows option. So,
>> withCharResult's "hPutStrLn stderr" causes problem. I fixed this problem
>> by using Debug.Trace.putTraceMsg instedad of hPutStrLn stderr.

-- 
shelarcy <shelarcy    hotmail.co.jp>
http://page.freett.com/shelarcy/