enable protocol versions down to the lowest version, or up to the highest version supported by the library, respectively.</p>

<p>Getters return 0 in case <b>ctx</b> or <b>ssl</b> have been configured to automatically use the lowest or highest version supported by the library.</p>

<p>Currently supported versions are <b>SSL3_VERSION</b>, <b>TLS1_VERSION</b>, <b>TLS1_1_VERSION</b>, <b>TLS1_2_VERSION</b>, <b>TLS1_3_VERSION</b> for TLS and <b>DTLS1_VERSION</b>, <b>DTLS1_2_VERSION</b> for DTLS.</p>

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