EVP_PKEY_CTX_add1_tls1_prf_seed() sets the seed to B<seedlen> bytes of B<seed>.
If a seed is already set it is appended to the existing value.
+=head1 STRING CTRLS
+
+The TLS PRF also supports string based control operations using
+L<EVP_PKEY_CTX_ctrl_str(3)>.
+The B<type> parameter "md" uses the supplied B<value> as the name of the digest
+algorithm to use.
+The B<type> parameters "secret" and "seed" use the supplied B<value> parameter
+as a secret or seed value.
+The names "hexsecret" and "hexseed" are similar except they take a hex string
+which is converted to binary.
+
=head1 NOTES
All these functions are implemented as macros.
=head1 SEE ALSO
L<EVP_PKEY_CTX_new(3)>,
-L<EVP_PKEY_derive(3)>,
+L<EVP_PKEY_CTX_ctrl_str(3)>,
+L<EVP_PKEY_derive(3)>
+
+=head1 COPYRIGHT
+
+Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+
+Licensed under the OpenSSL license (the "License"). You may not use
+this file except in compliance with the License. You can obtain a copy
+in the file LICENSE in the source distribution or at
+L<https://www.openssl.org/source/license.html>.
=cut