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Language lawyer note: std::random_device isn't guaranteed to be hardware-based, or anything in particular: http://en.cppreference.com/w/cpp/numeric/random/rand

• sjolsen 12y ago
  You are correct; and of course, any hardware-level behaviour is likely to be implementation defined. I should note that MSVC [1] guarantees "non-deterministic and cryptographically secure" behaviour; and that libc++ [2] uses the "cryptographically secure" rand_s [3] on Windows, NaCl on other platforms where NaCl is available, and /dev/urandom where it isn't. [1] http://msdn.microsoft.com/en-us/library/bb982250.aspx http://msdn.microsoft.com/en-us/library/bb982250.aspx [2] https://github.com/llvm-mirror/libcxx/blob/master/src/random.cpp https://github.com/llvm-mirror/libcxx/blob/master/src/random... [3] http://msdn.microsoft.com/en-us/library/sxtz2fa8.aspx http://msdn.microsoft.com/en-us/library/sxtz2fa8.aspx