[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mark Lawrence]

Changes by Mark Lawrence :


--
nosy:  -BreamoreBoy

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Sophie]

Sophie added the comment:

In case someone else need it, here is a patch for python 3.5.0b1

--
nosy: +Sopouic
versions: +Python 3.5 -Python 3.2, Python 3.3, Python 3.4
Added file: http://bugs.python.org/file43259/python-3.5.0b1-fdvalidation.patch

___
Python tracker 

___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Ilya Kulakov]

Ilya Kulakov added the comment:

Steve,

What's going to be the required msvc compiler for 3.5 on Windows?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[eryksun]

eryksun added the comment:

The 3.5 build uses MSVC 14 (VS 2015):

https://docs.python.org/3.5/using/windows.html#compiling-python-on-windows
https://hg.python.org/cpython/file/3.5/PCbuild/readme.txt

--
nosy: +eryksun

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Steve Dower]

Steve Dower added the comment:

Rereading the discussion, there seems to be agreement that this is an 
enhancement. It does not apply for Python 3.5 (which requires a compiler 
without the bug that causes this), and Python 3.4 is no longer eligible for 
enhancements. I'm closing this as out of date.

The patches will be here, so anyone who is rebuilding Python 3.4 or earlier for 
their own use with VS 2012 is welcome to apply the patch themselves.

--
resolution: fixed - out of date
status: open - closed
type:  - enhancement
versions:  -Python 3.5

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Ilya Kulakov]

Ilya Kulakov added the comment:

I see issue to be fixed but patch wasn't applied yet. Is it still supposed to 
be included in 3.5 or there is something wrong?

--
nosy: +Ilya.Kulakov

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

Re msg238016, I confirm python-3.5.0a2-fdvalidation.patch fixes the problem for 
Python 3.5.0a4 and VS2013.

The only issue I encountered was with HAVE_FSTAT which is missing from 
PC/pyconifg.h, so I edited the patch and removed the check if 
defined(HAVE_FSTAT). Does PC/pyconifg.h need update?

I also confirm vanilla Python 3.5.0a4 with VS2015RC does not require this 
patch, because the fileno regression/bug has been fixed in VS2015RC (details at 
https://connect.microsoft.com/VisualStudio/feedback/details/785119/).

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Jean-Charles Lefebvre]

Jean-Charles Lefebvre added the comment:

Well, just in case, I've attached the patch to apply against 3.5.0a2.

--
Added file: http://bugs.python.org/file38469/python-3.5.0a2-fdvalidation.patch

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Jean-Charles Lefebvre]

Jean-Charles Lefebvre added the comment:

Oops, mistyping, #ifdef test would be:

#if defined(MS_WINDOWS)  defined(HAVE_FSTAT)  defined(_MSC_VER)  _MSC_VER 
= 1700  _MSC_VER  1900

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Jean-Charles Lefebvre]

Jean-Charles Lefebvre added the comment:

Hi all, a small update to confirm this issue with version 3.5.0a2 embedded in a 
native C++ GUI application, having everything built with VS2013 SP4.

Same execution flow as described by Mateusz in msg198689.

I've modified Python/pylifecycle.c file according to Tomasz's attached patch.
It just works for me and I've just slightly modified the #ifdef line:

#if defined(MS_WINDOWS)  defined(HAVE_FSTAT)  defined(_MSC_VER)  _MSC_VER 
= 1700  _MSC_VER  2000

It would definitely be nice to have this workaround applied to the 3.5 branch 
since MS' fix is lost in release cycle. Would it be too intrusive?

--
nosy: +Jean-Charles Lefebvre
versions: +Python 3.5

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Steve Dower]

Steve Dower added the comment:

There's not much point putting this into 3.5 anymore, as we are going to break 
pre-VS2015 builds completely sooner or later (too many changes to the CRT that 
we can't just work around with #ifdefs - and too much opposition to having code 
purely to support unsupported compilers).

It's probably only worth putting this into 3.4 at this stage, which I'm okay 
with but I'm not going to push hard to make it happen. Also worth noting that 
the code here in 3.5 has diverged from 3.4, and so the attached patch doesn't 
apply.

Any of the other core devs strongly opposed to me updating 3.4 so people 
embedding that version can have the fix?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Tomasz Wasilczyk]

Tomasz Wasilczyk added the comment:

It seems that bug remains *not* fixed.

Just like eaducac pointed out, there are cases when underlying file handle is 
-2, which is not a valid file handle, but *is* a valid handle (which is 
GetCurrentThread).

Thus, provided dup solution accepts it, while it shouldn't. However, suggested 
GetStdHandle check still doesn't work for me. While working on the related 
Spoon issue, I've worked out a working solution (see the patch attached).

Tomek,
Spoon.net dev

--
keywords: +patch
nosy: +twasilczyk@spoon
Added file: http://bugs.python.org/file37907/python-3.3.5-fdvalidation.patch

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[STINNER Victor]

STINNER Victor added the comment:

@steve.dower: Do you have info on this issue?

--
nosy: +steve.dower

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Steve Dower]

Steve Dower added the comment:

This is fixed in VS2015 last time I tried it. I've proposed workarounds for 
this before, but it's never affected any official build do there's never been 
any traction. The fstat patch is normally the check that I use.

I don't know what Tomasz means that it's not fixed. Fixes like this don't 
magically appear in earlier VS versions, and while VS2015 does have the fix, 
it's not quite ready for production work.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Tomasz Wasilczyk]

Tomasz Wasilczyk added the comment:

I don't mean fixing VS, but providing a workaround in Python code, when 
compiled with VS2012.

I know newer VS versions are fixed. Do you mean, VS2012 is not supported? If 
it's not - then LibreOffice team have a problem, because their official release 
is built with this suite.

If it is supported, and you don't want to alter behavior for other versions, 
then a patch may also contain an ifdef for MSVC 11.0.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mark Lawrence]

Mark Lawrence added the comment:

An enhancement can only go into 3.5, not 3.4.  This has to happen before beta 1 
which is currently scheduled for May 24 2015.  I'm against the idea as it would 
create too many compatibility issues.

--
nosy: +BreamoreBoy

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Steve Dower]

Steve Dower added the comment:

It's not supported for building Python, is what I meant. I don't know what the 
status is for Microsoft support of VS2012, but I'd expect it's security fix 
only by now.

Being able to support building Python with alternative compilers is a task that 
we don't have the volunteers to support, especially on Windows. That said, I'm 
not against taking patches like this to improve it, but I'd expect they'll be 
treated as an enhancement and won't make it into any version before 3.4.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Tomasz Wasilczyk]

Tomasz Wasilczyk added the comment:

In such case, I agree it's an enhancement, not a bugfix. Could go into 3.5 
branch.

How about changing the ifdef to the following, to avoid any issues on 
non-MSVS2012:

#if defined(MS_WINDOWS)  defined(HAVE_FSTAT)  defined(_MSC_VER)  _MSC_VER 
== 1700

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Bastien Montagne]

Changes by Bastien Montagne b.mon...@gmail.com:


--
nosy: +mont29

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Brian Curtin]

Changes by Brian Curtin br...@python.org:


--
nosy:  -brian.curtin

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

FYI, I've got it confirmed fix for the bug in VS has been released [1]


We have fixed this behavior for the next major release, Visual Studio 14. The 
fix is present in the Visual Studio 14 CTP that was released earlier this 
month.


[1] 
https://connect.microsoft.com/VisualStudio/feedback/details/785119/fileno-stdin-0-for-non-console-application#tabs

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Luke Dunstan]

Changes by Luke Dunstan lukedunsta...@gmail.com:


--
nosy: +Luke.Dunstan
versions: +Python 3.4

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[eaducac]

eaducac added the comment:

Hi all,

I ran into this problem myself today with 3.3.2 and I thought I'd provide some 
more detail on what's going on. As has been described, prior to VC11, 
fileno(stdin) returned -2 in applications with no console, so is_valid_fd() was 
properly rejecting it and the standard streams were being set to None. With 
VC11, it now returns 0, and the NT handle that underlies the FILE object 
associated with file descriptor 0 is -2. The problem is that -2 is a 
pseudo-handle representing the current thread. dup() is simply a wrapper around 
the Windows API function DuplicateHandle(), so when dup() is called on file 
descriptor 0, it returns success because DuplicateHandle() is successfully 
creating a new handle referring to the current thread. It's not until the call 
to fstat() in check_fd() much later that the CRT realizes it's not dealing with 
a file.

I see in Mercurial that 3.3.4 and 3.4 that the is_valid_fd() code hasn't been 
changed. This is definitely a Microsoft bug, but if (as it sounds) they're not 
going to be able to fix it anytime soon, I think it would be  ideal to have a 
change for this in Python. Replacing this with check_fd() would fix it, or if 
you don't want to rely on fstat(), some Windows-specific code using 
GetStdHandle():

#ifdef MS_WINDOWS
if (!is_valid_fd(fd) || GetStdHandle(STD_INPUT_HANDLE) == NULL) {
#else
if (!is_valid_fd(fd)) {
#endif

That would have to be repeated for stdout and stderr using 
GetStdHandle(STD_OUTPUT_HANDLE) and GetStdHandle(STD_ERROR_HANDLE), as those 
descriptors have the same problem.

--
nosy: +eaducac
versions: +Python 3.3

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

I have just tested Windows GUI application built against Python 3.2.1 with 
is_valid_fd patch according to http://hg.python.org/cpython/rev/f15943505db0/

All built using VS2012.

Again, I can confirm that is_valid_fd does NOT solve the problem.
Here is extract of execution flow in initstdio function:

1. fd = 0, despite it is GUI app, see 
https://connect.microsoft.com/VisualStudio/feedback/details/785119/

fd = fileno(stdin);

2. is_valid_fd will return __true__, so it moves to calling create_stdio()

if (!is_valid_fd(fd)) {
   ...
}
else {
   std = create_stdio(iomod, fd, 0, stdin, encoding, errors);
   if (std == NULL)
   goto error;
}

3. The create_stdio() call fails though, causing error followed by abort


Still, the only solution that solves this problem in Windows GUI applications 
buitl using VS2012 is to use check_fd() function to check fd, instead of 
is_valid_fd(). The check_fd() is more reliable as it will return -1 due to 
errno == EBADF.

My previous attempt to analyse _PyVerify_fd() is not relevant for the problem, 
let's forget it.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc added the comment:

 2. _PyVerify_fd(fd) is always true. Given the current definition:
 #define _PyVerify_fd(fd) (_get_osfhandle(fd) = 0)
 for those values of fd _get_osfhandle(fd) = 0, always.

Hum, are you sure this is the selected implementation?
- this code is only in 2.7
  http://hg.python.org/cpython/file/v2.7/Include/fileobject.h#l73
- it's protected by #if statements. In your case the first case should be 
selected, can you verify if it's the case, and if not, why?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Daniel]

Daniel added the comment:

Here are some solutions which might help you until MS fixed the bug.

1) Even if the subsystem is Windows one solution is to call AllocConsole() 
before Py_Initialize() to create a console.

2) Second Solution: If you don't want to open a console and your application 
has its own output window you could redirect stdout/stderr/stdin with freopen 
to a temp file first. (e.g: freopen(file.txt,w,stdout);) Call freopen for 
all std handles before you call Py_Initialize(). You can keep the redirection 
to the file or after Py_Initialize() succeeded you change the redirection now 
in Python by redirect sys.stdout to the place you want.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Antoine Pitrou]

Changes by Antoine Pitrou pit...@free.fr:


--
nosy: +brian.curtin, tim.golden, tim.peters

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Antoine Pitrou]

Changes by Antoine Pitrou pit...@free.fr:


--
priority: normal - high
resolution: out of date - 
stage:  - needs patch
versions: +Python 3.3, Python 3.4 -Python 3.2

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Antoine Pitrou]

Antoine Pitrou added the comment:

Which 3.2 version does this break with? As far as I can tell, it should be 
fixed in 3.2.3: see changeset f15943505db0, issue #7111.

--
nosy: +pitrou
resolution:  - fixed
stage: needs patch - 
status: open - pending
versions: +Python 3.2 -Python 3.3, Python 3.4

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

@Antoine (Re msg197480)

I'm not sure which minor version of Python 3.2 it was, but in my comment in 
msg187362, I confirmed that I have tested the later version with added 
is_valid_fd function. As far as I understand, the changes in 
http://hg.python.org/cpython/rev/f15943505db0/ introduce that is_valid_fd 
function, which does not seem to solve the problem.

--
status: pending - open

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Daniel]

Daniel added the comment:

Sorry, I used the latest Python3.4 branch, I haven't tested this with prior 
versions.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Antoine Pitrou]

Antoine Pitrou added the comment:

 I'm not sure which minor version of Python 3.2 it was, but in my
 comment in msg187362, I confirmed that I have tested the later
 version with added is_valid_fd function. As far as I understand, the
 changes in http://hg.python.org/cpython/rev/f15943505db0/ introduce
 that is_valid_fd function, which does not seem to solve the problem.

Could you try to investigate this a bit further? Does is_valid_fd()
return true, and why?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

On 11 September 2013 12:34, Antoine Pitrou rep...@bugs.python.org wrote:
 I'm not sure which minor version of Python 3.2 it was, but in my
 comment in msg187362, I confirmed that I have tested the later
 version with added is_valid_fd function. As far as I understand, the
 changes in http://hg.python.org/cpython/rev/f15943505db0/ introduce
 that is_valid_fd function, which does not seem to solve the problem.

 Could you try to investigate this a bit further? Does is_valid_fd()
 return true, and why?

I have already checked that (see msg187362)

Shortly, is_valid_fd always returns true because fd  0 is always
false as my tests with Visual Studio 2012 (Visual C++ 11.0 (1700)
confirmed (see also bug report linked in msg188117)

assert(fdi == 0);
assert(fdo == 1);
assert(fde == 2);

IOW, fd is always larger than 0.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Antoine Pitrou]

Antoine Pitrou added the comment:

 Shortly, is_valid_fd always returns true because fd  0 is always
 false as my tests with Visual Studio 2012

Well, that's not all there is, is_valid_fd() does other checks before returning 
true.

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

On 12 September 2013 00:06, Antoine Pitrou rep...@bugs.python.org wrote:
 Shortly, is_valid_fd always returns true because fd  0 is always
 false as my tests with Visual Studio 2012

 Well, that's not all there is, is_valid_fd() does other checks before 
 returning true.

Given the function:

is_valid_fd(int fd)
{
int dummy_fd;
if (fd  0 || !_PyVerify_fd(fd))
return 0;
dummy_fd = dup(fd);
if (dummy_fd  0)
return 0;
close(dummy_fd);
return 1;
}

for fd values of 0, 1 or 2

1. fd  0 is always false
2. _PyVerify_fd(fd) is always true. Given the current definition:
#define _PyVerify_fd(fd) (_get_osfhandle(fd) = 0)
for those values of fd _get_osfhandle(fd) = 0, always.
3. for those fd values, dup() never returns fd  0

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Daniel]

Daniel added the comment:

After contacting Microsoft they answered that they cannot fix that within the 
VS2012 or VS2013 cycle. Very bad. Any ideas?

--
nosy: +m_python

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

This is still an issue in VS 2012 Version 11.0.60610.01 Update 3

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[V.E.O]

V.E.O added the comment:

Hi Christian,

The latest runtime Microsoft provided is buggy.
Tried fix the PyVerify_fd with more GetFileType verification. But a lot more 
problems came for isatty returns true in non-console program. The fix in Python 
side shall be large.
Details is reported to Microsoft, we can only hope they make it right.

--
status: pending - open

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[V.E.O]

V.E.O added the comment:

Tested on MSVCRT110.DLL (11.0.51106.1 released in 2012/11/05). 
Previous one 11.0.50727.1 released in 2012/07/26 does not have this problem.
This problem better be fixed in Python for MS does not have clear document.

--
nosy: +V.E.O

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Christian Heimes]

Christian Heimes added the comment:

Python 3.2 is in security fix mode. Bug fixes such as this issue don't count as 
security fix. Are you able to update to Python 3.3? Python 2.7 has a different 
implementation and uses FILE* instead of file descriptors.

--
components: +Windows
nosy: +christian.heimes
resolution:  - out of date
status: open - pending

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

I've just got an update on the bug report [1] I submitted to Microsoft.
The Visual C++ team confirmed It does appear to be a regression from Visual 
Studio 2010.

So, it's not a bug in Python, but I think it may be important for Python to 
consider applying some reliable workaround (i.e. use of check_fd() function)

[1] http://connect.microsoft.com/VisualStudio/feedback/details/785119/

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[STINNER Victor]

Changes by STINNER Victor victor.stin...@gmail.com:


--
nosy: +haypo

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

New submission from Mateusz Loskot:

In pythonrun.c, there is function initstdio() with the following test:

static int
initstdio(void)
{
...
/* Set sys.stdin */
fd = fileno(stdin);
/* Under some conditions stdin, stdout and stderr may not be connected
 * and fileno() may point to an invalid file descriptor. For example
 * GUI apps don't have valid standard streams by default.
 */
if (fd  0) {
#ifdef MS_WINDOWS
std = Py_None;
Py_INCREF(std);
#else
goto error;
#endif
}
else {
...
}

This function is fails for non-console applications (i.e. MFC) built using 
Visual C++ 11.0 (Visual Studio 2012), becasue **strangely**, fileno(stdin) == 
0, so this test results in false and Python initialisation routines attempt to 
setup streams.

Apparently, fileno(stdin) return value has changed between Visual C++ 10.0 (VS 
2010)
and 11.0. The VC++ 10.0 reports fileno(stdin) == -2.

--
components: IO, Interpreter Core
messages: 187351
nosy: mloskot
priority: normal
severity: normal
status: open
title: Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program
versions: Python 3.2

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc added the comment:

And does it cause an issue later? How?

--
nosy: +amaury.forgeotdarc

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

Yes, it does. In file Modulfileio.c, in function fileio_init, there is this 
code:

if (fd = 0) {
if (check_fd(fd))
goto error;
self-fd = fd;
self-closefd = closefd;
}

The check_fd tests:

if (!_PyVerify_fd(fd) || (fstat(fd, buf)  0  errno == EBADF)) {

The _PyVerify_fd(fd) == 1, but errno is Bad file descriptor.

This eventually leads to Py_InitializeEx failure at:

if (initstdio()  0)
Py_FatalError(
Py_Initialize: can't initialize sys standard streams);

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

 In file Modulfileio.c,

I messed the path and filename above I meant: In file Modules/_io/fileio.c,

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Amaury Forgeot d'Arc]

Amaury Forgeot d'Arc added the comment:

Maybe check_fd(fd) could be used in initstdio as well.

Can you check whether it's the same for the other files?
What are the values for fileno(stdout) and fileno(stderr)?

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com

[issue17797] Visual C++ 11.0 reports fileno(stdin) == 0 for non-console program

[Mateusz Loskot]

Mateusz Loskot added the comment:

Replacing if the current test in Python 3.2

if (fd  0)
with
if (check_fd(fd)  0)

Seems to be a working solution.

I just noticed, that in current Python/pythonrun.c in the repo, there the fd  
0 tests have been replaced with new function is_valid_fd(). But, its semantic 
is equivalent to fd  0, so it does not check anything really. Perhaps 
is_valid_fd could be redefined as check_fd.

Here are Visual C++ 11.0 (1700) vs 10.0 differences of fileno return value for 
all the standard streams

int fdi, fdo, fde;
fdi = fileno(stdin);
fdo = fileno(stdout);
fde = fileno(stderr);
#if _MSC_VER  1700
assert(fdi == -2);
assert(fdo == -2);
assert(fde == -2);
#else
assert(fdi == 0);
assert(fdo == 1);
assert(fde == 2);
#endif

By the way, I assume such sudden change in fileno(std*) behaviour between 
Visual C++ versions is suspicious, so I also submitted bug report to Visual 
Studio:
https://connect.microsoft.com/VisualStudio/feedback/details/785119/

--

___
Python tracker rep...@bugs.python.org
http://bugs.python.org/issue17797
___
___
Python-bugs-list mailing list
Unsubscribe: 
http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com