s() is a BIO_ctrl() macro which can be called to determine whether the decryption operation was successful.</p>

<p>BIO_get_cipher_ctx() is a BIO_ctrl() macro which retrieves the internal BIO cipher context. The retrieved context can be used in conjunction with the standard cipher routines to set it up. This is useful when BIO_set_cipher() is not flexible enough for the applications needs.</p>

<h1 id="NOTES">NOTES</h1>

<p>When encrypting BIO_flush() <b>must</b> be called to flush the final block through t