id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
11894,boost::python::file_exec not fully closing file with Python 3.4.3,alison.shaw@…,Ralf W. Grosse-Kunstleve,"Using Python 3.4.3 and Boost 1.57.0 on 64-bit Windows 7 with Visual Studio 2013.

After boost::python::exec_file is called on a file, that file can't be modified by the program using fopen_s, I think because it is still open.
Possibly related to #8058.

In the following example, when ModifyFile is called before executing the file, it succeeds. After the file has been executed, fopen_s returns 13 (Permission denied) and ModifyFile returns false. 

{{{
#include ""stdafx.h""
#include ""boost\python.hpp""
#include <iostream>

#define FILE_NAME         ""myTest.py""

void ModifyFile( std::string newContent )
{
  FILE* myFile = nullptr;
  errno_t result = fopen_s( &myFile, FILE_NAME, ""wb"" );
  if ( result == 0 )
  {
    fwrite( newContent.c_str( ), sizeof( byte ), newContent.length( ), myFile );
    fclose( myFile );
    std::cout << ""Success"" << std::endl;
    return;
  }

  std::cout << ""Failure"" << std::endl;
}

int main( int argc, char** argv )
{
  Py_Initialize( );

  ModifyFile( ""print(\""Hello\"")"" );

  boost::python::api::object mainNamespace = boost::python::import( ""__main__"" ).attr( ""__dict__"" );
  boost::python::exec_file( FILE_NAME, mainNamespace, mainNamespace );
  
  ModifyFile(""print(\""Goodbye\"")"");
  
  Py_Finalize( );
  return 0;
}
}}}

I have tried a similar example using std::fstream to modify the file, and this doesn't seem to have the same problems.

(Apologies for not using Github as per the component description - I didn't find more detailed instructions in the guidelines for reporting bugs.)",Bugs,closed,To Be Determined,python USE GITHUB,Boost 1.57.0,Problem,wontfix,,