SSL_session_reused.3ssl man page
SSL_session_reused — query whether a reused session was negotiated during handshake
#include <openssl/ssl.h> int SSL_session_reused(SSL *ssl);
Query, whether a reused session was negotiated during the handshake.
During the negotiation, a client can propose to reuse a session. The server then looks up the session in its cache. If both client and server agree on the session, it will be reused and a flag is being set that can be queried by the application.
The following return values can occur:
A new session was negotiated.
A session was reused.
ssl(3), SSL_set_session(3), SSL_CTX_set_session_cache_mode(3)