SSL_get0_group_name - get name of the group that was used for the key agreement of the current TLS

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       Licensed under the Apache License 2.0 (the "License").  You may not use this file except in compliance
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3.5.0                                              2025-06-04                          SSL_GET0_GROUP_NAME(3SSL)

SSL_get0_group_name() returns the name of the group that was used for the key agreement of the current
       TLS session establishment.

       This function was added in OpenSSL 3.2.

       SSL_get0_group_name - get name of the group that was used for the key agreement of the current TLS
       session establishment

       If non-NULL, SSL_get0_group_name() returns the name of the group that was used for the key agreement of
       the current TLS session establishment.  If SSL_get0_group_name() returns NULL, an error occurred;
       possibly no TLS session has been established. See also SSL_get_negotiated_group(3).

       Note that the return value is valid only during the lifetime of the SSL object ssl.

ssl(7), SSL_get_negotiated_group(3)

        #include <openssl/ssl.h>

        const char *SSL_get0_group_name(SSL *s);