Fix for

Fix for
==3768== Conditional jump or move depends on uninitialised value(s)
==3768==    at 0x4C22ED8: strlen (mc_replace_strmem.c:275)
==3768==    by 0x1081E60B: std::string::operator=(char const*) (in /usr/lib64/libstdc++.so.6.0.12)
==3768==    by 0x40757F29: UNV164::Read(std::basic_ifstream<char, std::char_traits<char> >&, UNV164::TRecord&) (UNV164_Structure.cxx:49)