SSL_get_default_timeout - get default session timeout value
 #include <openssl/ssl.h>
 long SSL_get_default_timeout(const SSL *ssl);
SSL_get_default_timeout() returns the default timeout value assigned to
  SSL_SESSION objects negotiated for the protocol valid for ssl.
Whenever a new session is negotiated, it is assigned a timeout value, after
  which it will not be accepted for session reuse. If the timeout value was not
  explicitly set using SSL_CTX_set_timeout(3), the hardcoded default
  timeout for the protocol will be used.
SSL_get_default_timeout() return this hardcoded value,
    which is 300 seconds for all currently supported protocols.
ssl(7), SSL_CTX_set_session_cache_mode(3),
  SSL_SESSION_get_time(3), SSL_CTX_flush_sessions(3),
  SSL_get_default_timeout(3)
Copyright 2001-2016 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License").
    You may not use this file except in compliance with the License. You can
    obtain a copy in the file LICENSE in the source distribution or at
    <https://www.openssl.org/source/license.html>.