[osgeo4w-dev] [osgeo4w] #357: python 2.7.4 dll conflicts

[OSGeo4W]

#357: python 2.7.4 dll conflicts
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Reporter:  maphew  |       Owner:  osgeo4w-dev@…              
    Type:  defect  |      Status:  new                        
Priority:  major   |   Component:  Package                    
 Version:          |    Keywords:  python                     
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Comment(by maphew):

 the sqlite problem has been fixed by removing `sqlite3.dll` from python-
 core package and making it require pkg-sqlite (which had been done for
 previous release, but I overlooked for this one).

 The issue arising from duplicate yet conflicting python27.dll's in PATH
 is, strictly speaking, not our problem unless the dupe is from within the
 o4w system (the ones reported aren't). I do have an idea to help people
 though and am interested in feedback on the soundness of it:

 If we replace `etc\ini\python.bat` with the below, on each invocation of
 osgeo4w shell it will search PATH for the presence of duplicate
 PythonXX.dll's and issue a warning if found.

 {{{
 SET PYTHONHOME=%OSGEO4W_ROOT%\apps\Python27
 @call :check_path
 SET PATH=%PATH%;%OSGEO4W_ROOT%\apps\Python27\Scripts
 goto :eof

 :check_path
     @echo off
     setlocal
     set _DLL=%PYTHONHOME:~-8,8%.dll
     for %%G in ("%path:;=" "%") do (
         if exist %%G\%_DLL% call :conflicted %%G %_DLL%
         )
     if exist %SYSTEMROOT%\SysWOW64\%_DLL% call :conflicted
 %SYSTEMROOT%\SysWOW64 %_DLL%
     if "%_delay%"=="yes" ping -n 10 localhost > nul
     endlocal
     goto :eof

 :conflicted
     echo.
     echo.   **** Possibly conflicting %2 found in
     echo.   **** %1
     echo.   Please see http://trac.osgeo.org/osgeo4w/wiki/pkg-python/xxxxx
     echo.
     set _delay=yes
     goto :eof
 }}}

 sample result:
 {{{
 B:\>SET PYTHONHOME=B:\o4w\\apps\Python27

    **** Possibly conflicting Python27.dll found in
    **** "C:\Program Files\TortoiseHg\"
    Please see http://trac.osgeo.org/osgeo4w/wiki/pkg-python/xxxxx


    **** Possibly conflicting Python27.dll found in
    **** C:\Windows\SysWOW64
    Please see http://trac.osgeo.org/osgeo4w/wiki/pkg-python/xxxxx


 B:\>
 }}}

 Why I'm a bit leary of this: a) a very simple 2 line batch file anyone can
 understand is a dozen times longer and leverages some arcane CMD
 processing ==> harder to maintain, b) if this becomes standard practice
 for every DLL issue we end up with a lot of special case code ==> harder
 to maintain. '''However''' in spite of this, it does seem to work and it
 would save time troubleshooting, especially for those whom the ini
 directory and shell setup is not usually even given a passing glance. Your
 thoughts?

-- 
Ticket URL: <http://trac.osgeo.org/osgeo4w/ticket/357#comment:1>
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