I'm using an asio::streambuf to read and write data to a socket. Despite my best efforts, I can't get the streambuf to throw an exception if I consume too much. I'm trying to get it to throw an exception so I can test an error case. The documentation says streambuf::consume will throw an std::length error if the requested amount to read is greater than the input stream size ( http://www.boost.org/doc/libs/1_42_0/doc/html/boost_asio/reference/basic_str...). But in my test program, this did not happen. Do I need to enable exception throwing somehow? Or is streambuf working as intended and not supposed to throw an exception? Here is my test program: #include <iostream> #include using namespace std; int main() { char in[] = "hello"; char out[6] = {0, 0, 0, 0, 0, 0}; boost::asio::streambuf s; s.sputn(in, sizeof(in)); s.sgetn(out, sizeof(in)); cout << out << endl << s.size() << endl; s.consume(1000); return 0; }