SSL_CTRL_SET_TLSEXT_OPAQUE_PRF_INPUT

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
version(!OPENSSL_NO_TLSEXT)
extern (C) nothrow
enum SSL_CTRL_SET_TLSEXT_OPAQUE_PRF_INPUT = 60;

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