SSL_CTRL_TLS_EXT_SEND_HEARTBEAT

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 && !OPENSSL_NO_HEARTBEATS)
extern (C) nothrow
enum SSL_CTRL_TLS_EXT_SEND_HEARTBEAT = 85;

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