underlying BIO.
If the underlying BIO is B<blocking>, SSL_read() will only return, once the
-read operation has been finished or an error occurred.
+read operation has been finished or an error occurred, except when a
+renegotiation take place, in which case a SSL_ERROR_WANT_READ may occur.
+This behaviour can be controlled with the SSL_MODE_AUTO_RETRY flag of the
+L<SSL_CTX_set_mode(3)|SSL_CTX_set_mode(3)> call.
If the underlying BIO is B<non-blocking>, SSL_read() will also return
when the underlying BIO could not satisfy the needs of SSL_read()
available. Call SSL_get_error() with the return value B<ret> to find out,
whether an error occurred.
-=item -1
+=item E<lt>0
The read operation was not successful, because either an error occurred
or action must be taken by the calling process. Call SSL_get_error() with the
=head1 SEE ALSO
L<SSL_get_error(3)|SSL_get_error(3)>, L<SSL_write(3)|SSL_write(3)>,
+L<SSL_CTX_set_mode(3)|SSL_CTX_set_mode(3)>,
L<ssl(3)|ssl(3)>, L<bio(3)|bio(3)>
=cut