For example in FilePath.cpp:

TString FilePath::FixPathForPlatform(const TString FileName) {
       TString result = FileName;
       size_t position = result(_T("\\?\""));

        if (position == TString::npos) {
            result = TString(_T("\\?\"")) + result;
        }

        return result;
}

bool FilePath::DeleteFile(const TString FileName) {
    bool result = false;

    if (FileExists(FileName) == true) {
#ifdef WINDOWS
        // To extend to long filenames prepend \\?\" to the filename.
        TString lFileName = FixPathForPlatform (FileName);
        FileAttributes attributes(lFileName);

        if (attributes.Contains(faReadOnly) == true) {
            attributes.Remove(faReadOnly);
        }

        result = ::DeleteFile(lFileName.data()) == TRUE;
#endif //WINDOWS
#ifdef POSIX
        if (unlink(StringToFileSystemString(FileName)) == 0) {
            result = true;
        }
#endif //POSIX
    }

    return result;
}