+page.
+
+=head1 NOTES
+
+It is possible to call EVP_OpenInit() twice in the same way as
+EVP_DecryptInit(). The first call should have B<priv> set to NULL
+and (after setting any cipher parameters) it should be called again
+with B<type> set to NULL.
+
+If the cipher passed in the B<type> parameter is a variable length
+cipher then the key length will be set to the value of the recovered
+key length. If the cipher is a fixed length cipher then the recovered
+key length must match the fixed cipher length.