Do action for all files in some directory on all drives in Symbian

In SDL there is a useful sample of how to run through all files in directory:

void ForAllMatchingFiles(RFs& aSession, const TDesC& aWildName, const TDesC& aScanDir)
    {
    TFindFile file_finder(aSession);
    CDir* file_list;
    TInt err = file_finder.FindWildByDir(aWildName,aScanDir, file_list);
    while (err==KErrNone)
        {
        TInt i;
        for (i=0; i < Count(); i++)
            {
            TParse fullentry;
            fullentry.Set((*file_list)[i].iName, &file_finder.File(),NULL);
            // Do something with the full Symbian OS filename
            DoOneFile(aSession, fullentry.FullName());
            }
        delete file_list;
        err=file_finder.FindWild(file_list);
        }
    }