Robert,
I have come across an issue with the current implementation of osgDB::appendPlatformSpecificLibraryFilePaths on Windows platforms. It is common practice on windows to place copies of the supporting dlls that your program loads in the same directory as the executable. The standard Win32 LoadLibrary function will look for dlls in the directory from which the program executable was loaded before searching in other standard places which will include the directories on the PATH environment variable. This behaviour allows an implementer to ensure that if dlls of the same name exist in places such as those on the PATH list that the version that is placed in the executable directory is used in preference, this is especially important if the dlls are unversioned as is the case with the standard build of osg plugins. The current implementation of appendPlatformSpecificLibraryFilePaths for windows populates the osg library file path with the contents of the PATH environment variable. The current implementation of osgDB::DynamicLibrary::LoadLibrary searches for the dll on this path and if it finds it, it passes the full path name to the windows LoadLibrary functions. This defeats that functions searching behaviour and in our case causes someone else's version of a plugin dll to be loaded because they had put an entry in the PATH environment variable. We have hit this problem in real life on user installations. The results can be messy. Curse the popularity of OSG :-). We have temporarily resolved this by explicitly setting the osg library path to empty in our applications. I would suggest that this should be the default behaviour for appendPlatformSpecificLibraryFilePaths on windows as appending the PATH contents and some system directories is in some cases wrong, as described above, and in most cases superfluous as osgDB::DynamicLibrary::LoadLibrary will call windows LoadLibrary with the bare file name if it cannot be found on the osg paths, windows LoadLibrary will then run its own search algorithm which will include the PATH environment variable and system directories. Comments anyone? I no one disagrees I will submit a patch. Roger
_______________________________________________ osg-users mailing list [email protected] http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
