If BIO_should_retry() is false then the cause is an error condition.
-BIO_should_read() is true if the cause of the condition is that a BIO
-needs to read data.
+BIO_should_read() is true if the cause of the condition is that the BIO
+has insufficient data to return. Check for readability and/or retry the
+last operation.
-BIO_should_write() is true if the cause of the condition is that a BIO
-needs to read data.
+BIO_should_write() is true if the cause of the condition is that the BIO
+has pending data to write. Check for writability and/or retry the
+last operation.
BIO_should_io_special() is true if some "special" condition, that is a
reason other than reading or writing is the cause of the condition.
worked around by only passing the relevant data to ASN1 functions when
the entire structure can be read or written.
+=head1 RETURN VALUES
+
+BIO_should_read(), BIO_should_write(), BIO_should_io_special(), and
+BIO_should_retry() return either 1 or 0 based on the actual conditions
+of the B<BIO>.
+
+BIO_retry_type() returns a flag combination presenting the cause of a retry
+condition or false if there is no retry condition.
+
+BIO_get_retry_BIO() returns a valid B<BIO> structure.
+
+BIO_get_retry_reason() returns the reason for a special condition.
+
=head1 SEE ALSO
L<bio>
=head1 COPYRIGHT
-Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
+Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
-Licensed under the OpenSSL license (the "License"). You may not use
+Licensed under the Apache License 2.0 (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>.