Popen4 -> null lines on Windows

[Patrick L. Nolan]

vincent wehren <vincent at visualtrans.de> wrote:
> "Patrick L. Nolan" <pln at cosmic.stanford.edu> schrieb im Newsbeitrag
> news:bsqil0$l3i$1 at news.Stanford.EDU...
> | We have an application that works on Linux.  It has to be ported
> | to Windows XP, and there's one bug that's driving me crazy.
> | There's a number-crunching program written in C++.  It is invoked
> | by a Tkinter python script.  The script uses the threading
> | module to separate out the heavy processing.  The worker thread
> | uses popen4 to run the C++ program and capture its standard
> | output.  This output is sent to the master thread through a
> | queue and displayed by the gui.
> |
> | As I said, it works on Linux.  On XP, every call to readline()
> | on the program's stdout returns only a zero-length string.
> | We are confident that the C++ program doesn't behave that
> | way.  We have tried both popen2.popen4 and win32pipe.popen4.
> |
> | Does this sound familiar to anyone?

> The output doesn't contain any low values by any chance? Does this also
> happen when the "mode" flag is set to "b" for binary?

It works the same with both "b" and "t".
-- 
*   Patrick L. Nolan                                          *
*   W. W. Hansen Experimental Physics Laboratory (HEPL)       * 
*   Stanford University                                       *