At the suggestion of Robert Ramey's, I have put together facets for reading and writing non-finite numbers, such as infinity and not-a-number, to text streams, in a consistent and portable way. The code, with documentation and tests, is available in the Boost Vault, serialization/non_finite_num_facets.zip. If there is enough interest in the code, I will submit it for a mini-review, in order to have it added to the serialization lib. --------------------------------------------- What does the code do? The following test fails on VC++ 7.1: stringstream s; double x = numeric_limits<double>::infinity(); double y; ss << x; ss >> y; assert(x == y); The situation gets even worse when text files are required to be portable between different platforms. But the following test succeeds: stringstream s; locale old_locale; locale tmp_locale(old_locale, new extended_num_put<char>); locale new_locale(tmp_locale, new extended_num_get<char>); s.imbue(new_locale); double x = numeric_limits<double>::infinity(); double y; ss << x; ss >> y; assert(x == y); For more info, read the documentation. ------------------------------------------------------------ --Johan Råde