SSL_get_rbio, SSL_get_wbio - get BIO linked to an SSL object

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       <https://www.openssl.org/source/license.html>.

3.5.0                                              2025-06-04                                 SSL_GET_RBIO(3SSL)

SSL_get_rbio() and SSL_get_wbio() return pointers to the BIOs for the read or the write channel, which
       can be different. The reference count of the BIO is not incremented.

       SSL_get_rbio, SSL_get_wbio - get BIO linked to an SSL object

       The following return values can occur:

       NULL
           No BIO was connected to the SSL object

       Any other pointer
           The BIO linked to ssl.

SSL_set_bio(3), ssl(7) , bio(7)

        #include <openssl/ssl.h>

        BIO *SSL_get_rbio(SSL *ssl);
        BIO *SSL_get_wbio(SSL *ssl);