Stderr and Pythonw

[vm_usenet]

Hi everyone,

I've seen this subject come up in another thread, but not getting
enough attention - so I'll just ask it:
When running python code via pythonw, what exactly happens to stderr?
I tried running code that, among else, writes to stderr - and at some
point I get an IOError claiming "Bad file descriptor".

Why is this happending?

Thanks in advance,

vm

[Dennis Lee Bieber]

Re: Stderr and Pythonw

On 29 Jun 2004 12:25:58 -0700, vm_usenet@yahoo .com (vm_usenet) declaimed
the following in comp.lang.pytho n:
[color=blue]
> When running python code via pythonw, what exactly happens to stderr?[/color]

You aren't invoking programs by typing "pythonw program.py" in a
command console window, are you?

pythonw was intended to be used for programs activated by
clicking on icons in Windows. As such, these programs are presumed to
have NO CONSOLE I/O, all I/O must be handled by the program creating a
window (GUI) or file and writing to that.

Since there is no console expected, none of the std***
connections are created.

--[color=blue]
> =============== =============== =============== =============== == <
> wlfraed@ix.netc om.com | Wulfraed Dennis Lee Bieber KD6MOG <
> wulfraed@dm.net | Bestiaria Support Staff <
> =============== =============== =============== =============== == <
> Home Page: <http://www.dm.net/~wulfraed/> <
> Overflow Page: <http://wlfraed.home.ne tcom.com/> <[/color]

[Manlio Perillo]

Re: Stderr and Pythonw

On Wed, 30 Jun 2004 04:22:16 GMT, Dennis Lee Bieber
<wlfraed@ix.net com.com> wrote:
[color=blue]
>On 29 Jun 2004 12:25:58 -0700, vm_usenet@yahoo .com (vm_usenet) declaimed
>the following in comp.lang.pytho n:
>[color=green]
>> When running python code via pythonw, what exactly happens to stderr?[/color]
>
> You aren't invoking programs by typing "pythonw program.py" in a
>command console window, are you?
>
> pythonw was intended to be used for programs activated by
>clicking on icons in Windows. As such, these programs are presumed to
>have NO CONSOLE I/O, all I/O must be handled by the program creating a
>window (GUI) or file and writing to that.
>
> Since there is no console expected, none of the std***
>connections are created.
>[/color]

This not really corrected.
Actually 'some' std*** connections are created but are usefulness
(and moreover they have a bug).

If you write more than 4096 an exception is raised...


Regards Manlio Perillo

[Peter Hansen]

Re: Stderr and Pythonw

Manlio Perillo wrote:
[color=blue]
> On Wed, 30 Jun 2004 04:22:16 GMT, Dennis Lee Bieber
> <wlfraed@ix.net com.com> wrote:[color=green]
>>On 29 Jun 2004 12:25:58 -0700, vm_usenet@yahoo .com (vm_usenet) declaimed
>>the following in comp.lang.pytho n:[color=darkred]
>>>When running python code via pythonw, what exactly happens to stderr?[/color]
>>
>> Since there is no console expected, none of the std***
>>connections are created.[/color]
>
> This not really corrected.
> Actually 'some' std*** connections are created but are usefulness
> (and moreover they have a bug).
>
> If you write more than 4096 an exception is raised...[/color]

And, for future reference, here is the bug report Manlio filed
on SourceForge (for which there is no response yet):

http://sourceforge.net/tracker/index.php?func=detail&aid=973507&group_id=5470&atid=105470

I've also confirmed this, using a test script very similar to one
Tim Peters posted a couple of months ago in

http://groups.google.ca/groups?selm=mailman.980.1082749579.20120.python-list%40python.org

The problem is confirmed to still exist with Python 2.3.4.

-Peter