B<OPENSSL_EC_EXPLICIT_CURVE> for explicit parameters (the default in versions
of OpenSSL before 1.1.0) or B<OPENSSL_EC_NAMED_CURVE> to use named curve form.
For maximum compatibility the named curve form should be used. Note: the
B<OPENSSL_EC_EXPLICIT_CURVE> for explicit parameters (the default in versions
of OpenSSL before 1.1.0) or B<OPENSSL_EC_NAMED_CURVE> to use named curve form.
For maximum compatibility the named curve form should be used. Note: the